Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.fct.2020.111235

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.neuint.2019.104608

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Epidemiological studies have shown that coffee consumption decreases the risk of Parkinson’s disease (PD). Caffeic acid (CA) and chlorogenic acid (CGA) are coffee components that have antioxidative properties. Rotenone, a mitochondrial complex I inhibitor, has been used to develop parkinsonian models, because the toxin induces PD-like pathology. Here, we examined the neuroprotective effects of CA and CGA against the rotenone-induced degeneration of central dopaminergic and peripheral enteric neurons. Male C57BL/6J mice were chronically administered rotenone (2.5 mg/kg/day), subcutaneously for four weeks. The animals were orally administered CA or CGA daily for 1 week before rotenone exposure and during the four weeks of rotenone treatment. Administrations of CA or CGA prevented rotenone-induced neurodegeneration of both nigral dopaminergic and intestinal enteric neurons. CA and CGA upregulated the antioxidative molecules, metallothionein (MT)-1,2, in striatal astrocytes of rotenone-injected mice. Primary cultured mesencephalic or enteric cells were pretreated with CA or CGA for 24 h, and then further co-treated with a low dose of rotenone (1–5 nM) for 48 h. The neuroprotective effects and MT upregulation induced by CA and CGA in vivo were reproduced in cultured cells. Our data indicated that intake of coffee components, CA and CGA, enhanced the antioxidative properties of glial cells and prevents rotenone-induced neurodegeneration in both the brain and myenteric plexus.

DOI： 10.3390/cells8030221

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

In previous studies, we found regional differences in the induction of antioxidative molecules in astrocytes against oxidative stress, postulating that region-specific features of astrocytes lead region-specific vulnerability of neurons. We examined region-specific astrocytic features against dopaminergic neurotoxin 6-hydroxydopamine (6-OHDA) as an oxidative stress using co-culture of mesencephalic neurons and mesencephalic or striatal astrocytes in the present study. The 6-OHDA-induced reduction of mesencephalic dopamine neurons was inhibited by co-culturing with astrocytes. The co-culture of midbrain neurons with striatal astrocytes was more resistant to 6-OHDA than that with mesencephalic astrocytes. Furthermore, glia conditioned medium from 6-OHDA-treated striatal astrocytes showed a greater protective effect on the 6-OHDA-induced neurotoxicity and oxidative stress than that from mesencephalic astrocytes. The cDNA microarray analysis showed that the number of altered genes in both mesencephalic and striatal astrocytes was fewer than that changed in either astrocyte. The 6-OHDA treatment, apparently up-regulated expressions of Nrf2 and some anti-oxidative or Nrf2-regulating phase II, III detoxifying molecules related to glutathione synthesis and export in the striatal astrocytes but not mesencephalic astrocytes. There is a profound regional difference of gene expression in astrocytes induced by 6-OHDA. These results suggest that protective features of astrocytes against oxidative stress are more prominent in striatal astrocytes, possibly by secreting humoral factors in striatal astrocytes.

DOI： 10.3390/ijms20030598

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Bentham Science Publishers Ltd.  

DOI： 10.2174/1381612823666170710163731

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Authorship：Lead author,　Corresponding author   Language：English  

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Astrocytes but not neurons express cystine/glutamate exchange transporter (xCT), which takes up cystine, and consequently supplies the substrate for GSH synthesis in neurons. It is recognized that GSH synthesis in neurons is dependent on the expression of xCT in astrocytes. Previous studies reported that levetiracetam (LEV), an anti-epileptic drug, increased xCT expression invivo. The purpose of this study was to examine neuroprotective effects of LEV in parkinsonian models and demonstrate xCT in astrocytes as a target of neuroprotection against dopaminergic neurodegeneration. We identified striatal astrocytes cultured with LEV showed significant increase in xCT expression and GSH levels. Preincubation of primary cultured mesencephalic dopamine neurons with conditioned media from LEV-treated astrocytes protected against 6-hydroxydopamine (6-OHDA)-induced neurotoxicity. These protective effects were canceled by xCT inhibitor. Furthermore, reduction of nigrostriatal dopaminergic neurons in 6-OHDA-lesioned parkinsonian mice was significantly abrogated by repeated injections of LEV. Treatment with LEV significantly increased the expression of xCT in striatal astrocytes in the hemi-parkinsonian mice. In conclusion, LEV exerts neuroprotective effects against neurodegeneration via up-regulation of xCT and GSH in astrocytes. Thus, xCT in astrocytes could be a potential target in novel neuroprotective approaches to prevent degeneration of dopaminergic neurons.

DOI： 10.1111/jnc.13405

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：BENTHAM SCIENCE PUBL LTD  

Astrocytes are the most abundant neuron-supporting glial cells in the central nervous system. The neuroprotective role of astrocytes has been demonstrated in various neurological disorders such as amyotrophic lateral sclerosis, spinal cord injury, stroke and Parkinson's disease (PD). Astrocyte dysfunction or loss-of-astrocytes increases the susceptibility of neurons to cell death, while astrocyte transplantation in animal studies has therapeutic advantage. We reported recently that stimulation of serotonin 1A (5-HT1A) receptors on astrocytes promoted astrocyte proliferation and upregulated antioxidative molecules to act as a neuroprotectant in parkinsonian mice. PD is a progressive neurodegenerative disease with motor symptoms such as tremor, bradykinesia, rigidity and postural instability, that are based on selective loss of nigrostriatal dopaminergic neurons, and with non-motor symptoms such as orthostatic hypotension and constipation based on peripheral neurodegeneration. Although dopaminergic therapy for managing the motor disability associated with PD is being assessed at present, the main challenge remains the development of neuroprotective or disease-modifying treatments. Therefore, it is desirable to find treatments that can reduce the progression of dopaminergic cell death. In this article, we summarize first the neuroprotective properties of astrocytes targeting certain molecules related to PD. Next, we review neuroprotective effects induced by stimulation of 5-HT1A receptors on astrocytes. The review discusses new promising therapeutic strategies based on neuroprotection against oxidative stress and prevention of dopaminergic neurodegeneration.

DOI： 10.2174/0929867323666160122115057

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Authorship：Lead author,　Corresponding author   Language：English  

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Astrocytes are abundant neuron-supporting glial cells that harbor a powerful arsenal of neuroprotective antioxidative molecules and neurotrophic factors. Here we examined whether enrichment with healthy striatal astrocytes can provide neuroprotection against progressive dopaminergic neurodegeneration. Serotonin 1A (5-HT1A) agonist 8-OH-DPAT induced astrocyte proliferation and increased metallothionein-1/-2 (MT-1/-2), antioxidative molecules, in cultured astrocytes and the striatum of mice. Primary cultured mesencephalic dopamine neurons were protected against oxidative stress by preincubation with conditioned media from 8-OH-DPAT-treated astrocytes. These protective effects were canceled by 5-HT1A antagonist or MT-1/-2-specific antibody. Furthermore, reduction of nigrostriatal dopaminergic neurons in 6-hydroxydopamine-lesioned parkinsonian model mice was significantly abrogated by repeated injections of 8-OH-DPAT. Treatment with 8-OH-DPAT markedly increased the expression of MT in striatal astrocytes in the hemi-parkinsonian mice. Our study provides a promising therapeutic strategy of neuroprotection against oxidative stress and progressive dopaminergic neurodegeneration by demonstrating the efficacy of targeting 5-HT1A receptors in astrocytes. © 2013 Elsevier Inc.

DOI： 10.1016/j.nbd.2013.08.003

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-LISS  

Our previous studies demonstrated the involvement of quinone formation in dopaminergic neuron dysfunction in the L-DOPA-treated parkinsonian model and in methamphetamine (METH) neurotoxicity. We further reported that the cysteine-rich metal-binding metallothionein (MT) family of proteins protects dopaminergic neurons against dopamine (DA) quinone neurotoxicity by its quinone-quenching property. The aim of this study was to examine MT induction in astrocytes in response to excess DA and the potential neuroprotective effects of astrocyte-derived MTs against DA quinone toxicity. DA exposure significantly upregulated MT-1/-2 in cultured striatal astrocytes, but not in mesencephalic neurons. This DA-induced MT upregulation in astrocytes was blocked by treatment with a DA-transporter (DAT) inhibitor, but not by DA-receptor antagonists. Expression of nuclear factor erythroid 2-related factor (Nrf2) and its binding activity to antioxidant response element of MT-1 gene were significantly increased in the astrocytes after DA exposure. Nuclear translocation of Nrf2 was suppressed by the DAT inhibitor. Quinone formation and reduction of mesencephalic DA neurons after DA exposure were ameliorated by preincubation with conditioned media from DA-treated astrocytes. These protective effects were abrogated by MT-1/-2-specific antibody. Adding exogenous MT-1 to glial conditioned media also showed similar neuroprotective effects. Furthermore, MT-1/-2 expression was markedly elevated specifically in reactive astrocytes in the striatum of L-DOPA-treated hemi-parkinsonian mice or METH-injected mice. These results suggested that excess DA taken up by astrocytes via DAT upregulates MT-1/-2 expression specifically in astrocytes, and that MTs or related molecules secreted specifically by astrocytes protect dopaminergic neurons from damage through quinone quenching and/or scavenging of free radicals. (C)2010 Wiley-Liss, Inc.

DOI： 10.1002/glia.21112

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Objective: Recent double-blind, controlled trials in Japan showed that the antiepileptic agent zonisamide (ZNS)improves the cardinal symptoms of Parkinson's disease. Glutathione (GSH) exerts antioxidative activity through quenching reactive oxygen species and dopamine quinone. GSH depletion within dopaminergic neurons impairs mitochondrial complex I activity, followed by age-dependent nigrostriatal neurodegeneration. This study examined changes in GSH and GSH synthesis-related molecules, and the neuroprotective effects of ZNS on dopaminergic neurodegeneration using 6-hydroxydopamine-injected hemiparkinsonian mice brain and cultured neurons or astrocytes.
Methods and Results: ZNS increased both the cell number and GSH levels in astroglial C6 cells, but not in dopaminergic neuronal CATH.a cells. Repeated injections of ZNS (30mg/kg intraperitoneally) for 14 days also significantly increased GSH levels and S100 beta-positive astrocytes in mouse basal ganglia. Repeated ZNS injections (30mg/kg) for 7 days in the hemiparkinsonian mice increased the expression of cystine/glutamate exchange transporter xCT in activated astrocytes, which supply cysteine to neurons for GSH synthesis. Treatment of these mice with ZNS also increased GSH levels and completely suppressed striatal levodopa-induced quinone formation. Reduction of nigrostriatal dopamine neurons in the lesioned side of hemiparkinsonian mice was significantly abrogated by repeated injections of ZNS with or without adjunctive levodopa starting 3 weeks after 6-hydroxydopamine lesioning.
Interpretation: These results provide new pharmacological evidence for the effects of ZNS. ZNS markedly increased GSH levels by enhancing the astroglial cystine transport system and/or astroglial proliferation via S100 beta production or secretion. ZNS acts as a neuroprotectant against oxidative stress and progressive dopaminergic neurodegeneration. ANN NEUROL 2010;67:239-249

DOI： 10.1002/ana.21885

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Authorship：Lead author,　Corresponding author   Language：English   Publisher：SPRINGER/PLENUM PUBLISHERS  

Dopamine (DA) and its metabolites containing two hydroxyl residues exert cytotoxicity in dopaminergic neuronal cells, primarily due to the generation of highly reactive DA and DOPA quinones. Quinone formation is closely linked to other representative hypotheses such as mitochondrial dysfunction, inflammation, oxidative stress, and dysfunction of the ubiquitin-proteasome system, in the pathogenesis of neurodegenerative diseases such as Parkinson's disease and methamphetamine-induced neurotoxicity. Therefore, pathogenic effects of the DA quinone have focused on dopaminergic neuron-specific oxidative stress. Recently, various studies have demonstrated that some intrinsic molecules and several drugs exert protective effects against DA quinone-induced damage of dopaminergic neurons. In this article, we review recent studies on some neuroprotective approaches against DA quinone-induced dysfunction and/or degeneration of dopaminergic neurons.

DOI： 10.1007/s11064-008-9843-1

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Authorship：Lead author,　Corresponding author   Language：English   Publisher：OKAYAMA UNIV MED SCHOOL  

Oxidative stress, including the reactive oxygen or nitrogen species generated in the enzymatical oxidation or auto-oxidation of an excess amount of dopamine, is thought to play an important role in dopaminergic neurotoxicity. Dopamine and its metabolites containing 2 hydroxyl residues exert cytotoxicity in dopaminergic neuronal cells, primarily due to the generation of highly reactive dopamine and DOPA quinones. Dopamine and DOPA quinones may irreversibly alter protein function through the formation of 5-cysteinyl-catechols on the proteins. Furthermore, the quinone formation is closely linked to other representative hypotheses such as mitochondrial dysfunction, inflammation, oxidative stress, and dysfunction of the ubiquitin-proteasome system, in the pathogenesis of neurodegenerative diseases. Therefore, pathogenic effects of the dopamine quinone have recently focused on dopaminergic neuron-specific oxidative stress. In this article, we primarily review recent studies on the pathogenicity of quinone formation, in addition to several neuroprotective approaches against dopamine quinone-induced dysfunction of dopaminergic neurons.

DOI： 10.18926/AMO/30980

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Dopamine (DA) quinone as DA neuron-specific oxidative stress conjugates with cysteine residues in functional proteins to form quinoproteins. Here, we examined the effects of cysteine-rich metal-binding proteins, metallothionein (NIT)-1 and -2, on DA quinone-induced neurotoxicity. NIT quenched DA semiquinones in vitro. In dopaminergic cells, DA exposure increased quinoproteins and decreased cell viability; these were ameliorated by pretreatment with MT-inducer zinc. Repeated L-DOPA administration markedly elevated striatal quinoprotein levels and reduced the DA nerve terminals specifically on the lesioned side in NIT-knockout parkinsonian mice, but not in wild-type mice. Our results suggested that intrinsic NIT protects against L-DOPA-induced DA quinone neurotoxicity in parkinsonian mice by its quinone-quenching property. (c) 2007 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

DOI： 10.1016/j.febslet.2007.09.046

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

Recently, the neurotoxicity of dopamine (DA) quinone formation by auto-oxidation of DA has focused on dopaminergic neuron-specific oxidative stress. In the present study, we examined DA quinone formation in methamphetamine (METH)-induced dopaminergic neuronal cell death using METH-treated dopaminergic cultured CATH.a cells and METH-injected mouse brain. In CATH.a cells, METH treatment dose-dependently increased the levels of quinoprotein (protein-bound quinone) and the expression of quinone reductase in parallel with neurotoxicity. A similar increase in quinoprotein levels was seen in the striatum of METH (4 mg/kg X4, i.p., 2 h interval)-injected BALB/c mice, coinciding with reduction of DA transporters. Furthermore, pretreatment of CATH.a cells with quinone reductase inducer, butylated hydroxyanisole, significantly and dose-dependently blocked METH-induced elevation of quinoprotein, and ameliorated METH-induced cell death. We also showed the protective effect of tyrosinase, which rapidly oxidizes DA and DA quinone to form stable melanin, against METH-induced dopaminergic neurotoxicity in vitro and in vivo using tyrosinase null mice. Our results indicate that DA quinone formation plays an important role, as a dopaminergic neuron-specific neurotoxic factor, in METH-induced neurotoxicity, which is regulated by quinone formation-related molecules.

DOI： 10.1096/fj.05-4996fje

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Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1096/fj.05-4996fje

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The neurotoxicity of dopamine (DA) quinones that appears in dopaminergic neuron-specific oxidative stress has recently been shown to play a role in the pathogenesis and/or progression of Parkinson disease. To clarify the effects of a DA agonist, pergolide, on the levodopa-induced elevation of quinones, the authors examined, striatal changes in quinoprotein using a hemi-parkinsonian mouse model. The level of striatal quinoprotein was significantly elevated specifically on the parkinsonian side, but not on the control side, after repeated levodopa administration. This levodopa-induced increase in striatal quinoprotein was almost completely suppressed by adjunctive administration with pergolide on the lesioned side. Furthermore, it was clarified that pergolide scavenged DA-semiquinones generated in vitro in a dose-dependent manner. These suppressive and quenching effects of pergolide against cytotoxic DA quinones may play a key role in its neuroprotective mechanism in the parkinsonian brain. Copyright © 2005 by Lippincott Williams &amp
Wilkins.

DOI： 10.1097/01.wnf.0000175523.33334.24

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Expression of dopamine receptors (DA-Rs) in astrocytes was examined in vitro and in vivo using primary cultured astrocytes and brain slices from rat basal ganglia. Astrocytes from basal ganglia expressed DA D1-, D3-, D4- and D5-receptors and D4-mediated signal transduction in response to DA, suggesting possible involvement of astrocytes in the pharmacological action of atypical antipsychotic drugs and in DA response in some neurological diseases. © 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.brainres.2004.09.014

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/s0168-0102(02)00057-3

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DOI： 10.1016/s0304-3940(00)01488-9

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1023/a:1020953913490

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DOI： 10.1016/j.neulet.2023.137598

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Sterile alpha and Toll/interleukin receptor motif-containing protein 1 (SARM1) is a NAD+ hydrolase that plays a key role in axonal degeneration and neuronal cell death. We reported that c-Jun N-terminal kinase (JNK) activates SARM1 through phosphorylation at Ser-548. The importance of SARM1 phosphorylation in the pathological process of Parkinson's disease (PD) has not been determined. We thus conducted the present study by using rotenone (an inducer of PD-like pathology) and neurons derived from induced pluripotent stem cells (iPSCs) from healthy donors and a patient with familial PD PARK2 (FPD2). The results showed that compared to the healthy neurons, FPD2 neurons were more vulnerable to rotenone-induced stress and had higher levels of SARM1 phosphorylation. Similar cellular events were obtained when we used PARK2-knockdown neurons derived from healthy donor iPSCs. These events in both types of PD-model neurons were suppressed in neurons treated with JNK inhibitors, Ca2+-signal inhibitors, or by a SARM1-knockdown procedure. The degenerative events were enhanced in neurons overexpressing wild-type SARM1 and conversely suppressed in neurons overexpressing the SARM1-S548A mutant. We also detected elevated SARM1 phosphorylation in the midbrain of PD-model mice. The results indicate that phosphorylated SARM1 plays an important role in the pathological process of rotenone-induced neurodegeneration.

DOI： 10.1093/jb/mvad068

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DOI： 10.1007/s12640-021-00402-5

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Other Link： https://link.springer.com/article/10.1007/s12640-021-00402-5/fulltext.html

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Anxiety-like behavior induced by a combination of doxorubicin and cyclophosphamide may be mediated by serotonin (5-HT)2A receptor hyperactivity. The anxiolytic effects of fluoxetine may be inhibited by this combination. The present study examined the mechanisms underlying anxiety-like behavior induced by the combination doxorubicin and cyclophosphamide in rats. Anxiety-like behavior was induced during a light-dark test by the doxorubicin and cyclophosphamide treatment (once a week for 2 weeks). 5-HT2A receptor and 5-HT2A receptor-mediated extracellular signal-related kinase (ERK)1/2 levels were measured using Western blotting. 5-HT reuptake activity in fluoxetine-treated rats was also examined using microdialysis. ( ±)-1-(2,5-Dimethoxy-4-iodophenyl)-2-aminopropane, a 5-HT2A receptor agonist, induced anxiety-like behavior. The fluoxetine treatment increased extracellular 5-HT concentrations in the hippocampus of vehicle- and doxorubicin and cyclophosphamide-treated rats. 5-HT transporter levels in the hippocampus were not affected by chemotherapy. The doxorubicin and cyclophosphamide treatment did not alter 5-HT2A receptor levels in the frontal cortex. However, chemotherapy increased 5-HT2A receptor-mediated ERK1/2 phosphorylation levels significantly more than the vehicle treatment. The present results suggest that anxiety-like behavior induced by the combination of doxorubicin and cyclophosphamide is mediated by 5-HT2A receptor hyperactivity without an increase in 5-HT2A receptor levels in rats.

DOI： 10.1007/s00213-021-05979-5

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Glutathione (GSH) is the most abundant intrinsic antioxidant in the central nervous system, and its substrate cysteine readily becomes the oxidized dimeric cystine. Since neurons lack a cystine transport system, neuronal GSH synthesis depends on cystine uptake via the cystine/glutamate exchange transporter (xCT), GSH synthesis, and release in/from surrounding astrocytes. Transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2), a detoxifying master transcription factor, is expressed mainly in astrocytes and activates the gene expression of various phase II drug-metabolizing enzymes or antioxidants including GSH-related molecules and metallothionein by binding to the antioxidant response element (ARE) of these genes. Accumulating evidence has shown the involvement of dysfunction of antioxidative molecules including GSH and its related molecules in the pathogenesis of Parkinson’s disease (PD) or parkinsonian models. Furthermore, we found several agents targeting GSH synthesis in the astrocytes that protect nigrostriatal dopaminergic neuronal loss in PD models. In this article, the neuroprotective effects of supplementation and enhancement of GSH and its related molecules in PD pathology are reviewed, along with introducing new experimental findings, especially targeting of the xCT-GSH synthetic system and Nrf2–ARE pathway in astrocytes.

DOI： 10.3390/ijms22168689

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：S. Karger AG  

<b><i>Background:</i></b> Cancer patients can suffer from psychological and cognitive disorders after chemotherapy, which influence quality of life. <b><i>Objective:</i></b> Oxidative stress may contribute to the psychological and cognitive disorders induced in rats by chemotherapy. In the present study, we examined the effects of N-acetylcysteine, an anti-oxidant, on anxiety-like behavior and cognitive impairment in rats treated with a combination of doxorubicin and cyclophosphamide. <b><i>Methods:</i></b> Rats were intraperitoneally injected with doxorubicin and cyclophosphamide once a week for 2 weeks. The light-dark test and the novel location recognition test were used to assess anxiety-like behavior and spatial cognition, respectively. The rats’ hippocampal levels of glutathione (GSH) and glutathione disulfide (GSSG) were measured using a GSSG/GSH quantification kit. <b><i>Results:</i></b> Combined treatment with doxorubicin and cyclophosphamide produced anxiety-like behavior and cognitive impairment in rats. N-acetylcysteine reversed the anxiety-like behavior and inhibition of novel location recognition induced by the combination treatment. Furthermore, the combination of doxorubicin and cyclophosphamide significantly reduced the rats’ hippocampal GSH/GSSG ratios. N-acetylcysteine reversed the reduction in the GSH/GSSG ratio seen in the doxorubicin and cyclophosphamide-treated rats. <b><i>Conclusion:</i></b> These results suggest that N-acetylcysteine inhibits doxorubicin and cyclophosphamide-induced anxiety-like behavior and cognitive impairment by reducing oxidative stress in the hippocampus.

DOI： 10.1159/000512117

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japanese Pharmacological Society  

Recently, it has been reported that dysfunction of astrocytes is involved vulnerability of neuronal cells in several neurological disorders. Glutathione (GSH) is the most abundant intrinsic antioxidant in the central nervous system, and its substrate cysteine is readily becomes the oxidized dimeric cystine. Since neurons lack a cystine transport system, neuronal GSH synthesis depends on cystine uptake via the cystine/glutamate exchange transporter (xCT), GSH synthesis and release in/from surrounding astrocytes. The expression and release of the zinc-binding protein metallothionein (MT) in astrocytes, which is a strong antioxidant, is induced and exerts neuroprotective in the case of dopaminergic neuronal damage. In addition, the transcription factor Nrf2 induces expression of MT-1 and GSH related molecules. We previously revealed that several antiepileptic drugs, serotonin 5-HT1A receptor agonists, plant-derived chemicals (phytochemicals) increased xCT expression, Nrf2 activation, GSH or MT expression and release in/from astrocytes, and exerted a neuroprotective effect against dopaminergic neurodegeneration in Parkinson’s disease model. Our serial studies on neuroprotection via antioxidant defense mechanism of astrocytes have found three target molecular systems of astrocytes for neuroprotection: (1) xCT-GSH synthetic system, (2) Nrf2 system and (3) 5-HT1A receptor-Nrf2-MT system, 5-HT1A-S100β system. In this article, possible neuroprotective strategy for Parkinson’s disease has been reviewed targeting antioxidative molecules in astrocytes.

DOI： 10.1254/fpj.20071

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japanese Pharmacological Society  

Parkinson’s disease (PD) is a progressive neurodegenerative disease with motor symptoms, such as tremor, akinesia/bradykinesia, rigidity and postural instability due to a loss of nigrostriatal dopaminergic neurons
PD patients also exhibit non-motor symptoms, such as hyposmia, orthostatic hypotension and constipation, which precede motor symptoms. Pathologically, Lewy bodies and neurites, which contains α-synuclein, are observed in the central and peripheral nervous system. To date, it is hypothesized that PD pathology appears first in the olfactory bulb and the enteric nervous system, and propagates progressively through the substantia nigra to finally reach the cerebral cortex. Major medications at present are nosotropic treatments to improve motor dysfunction in PD. Therefore, development of disease-modifying drug is required to slow or prevent PD progression. Astrocytes are known to play an important role in the maintenance of the neuronal environment and exert neuroprotective effects by production of antioxidants and neurotrophic factors and clearing toxic molecules. In the previous study, we demonstrated that astrocytes produced antioxidative molecules metallothionein (MT)-1/2 in response to oxidative stress and protected dopaminergic neurons against oxidative stress. MTs are cysteine-rich proteins possessing antioxidative properties. MTs bind to metals such as zinc (Zn) and copper (Cu) and function in metal homeostasis and detoxification
MTs regulate Zn-mediated transcriptional activation of various genes. Recently, it is reported that MTs prevent Cu-induced aggregation of α-synuclein. In this article, we review a new therapeutic strategy of neuroprotection in PD by targeting MTs in astrocytes.

DOI： 10.1254/fpj.20082

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DOI： 10.1007/s11419-020-00527-w

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Crossed cerebellar diaschisis (CCD) is a state of hypoperfusion and hypometabolism in the contralesional cerebellar hemisphere caused by a supratentorial lesion, but its pathophysiology is not fully understood. We evaluated chronological changes in cerebellar blood flow (CbBF) and gene expressions in the cerebellum using a rat model of transient middle cerebral artery occlusion (MCAO). CbBF was analyzed at two and seven days after MCAO using single photon emission computed tomography (SPECT). DNA microarray analysis and western blotting of the cerebellar cortex were performed and apoptotic cells in the cerebellar cortex were stained. CbBF in the contralesional hemisphere was significantly decreased and this lateral imbalance recovered over one week. Gene set enrichment analysis revealed that a gene set for “oxidative phosphorylation” was significantly upregulated while fourteen other gene sets including “apoptosis”, “hypoxia” and “reactive oxygen species” showed a tendency toward upregulation in the contralesional cerebellum. MCAO upregulated the expressions of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) in the contralesional cerebellar cortex. The number of apoptotic cells increased in the molecular layer of the contralesional cerebellum. Focal cerebral ischemia in our rat MCAO model caused CCD along with enhanced expression of genes related to oxidative stress and apoptosis.

DOI： 10.3390/ijms21114137

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Pharmaceutical Society of Japan  

DOI： 10.1248/bpb.b19-00025

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We examined whether combination treatment with doxorubicin and cyclophosphamide, a traditional chemotherapy for breast cancer, induced anxiety-like behavior in rats. Furthermore, we evaluated the role of the serotonin (5-HT)2A receptor subtype in the anxiety-like behavior induced by such chemotherapy. Rats were intraperitoneally injected with doxorubicin and cyclophosphamide once a week for 2 weeks. This caused the rats to display anxiety-like behavior during the light-dark test. In addition, we examined the rats' 5-HT2A receptor-mediated behavioral responses. Combination treatment with doxorubicin and cyclophosphamide significantly increased (±)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane, (a 5-HT2A receptor agonist)-induced wet-dog shake activity. This anxiety-like behavior was significantly inhibited by mirtazapine, a 5-HT2A receptor antagonist/5-HT1A receptor agonist, and tandospirone, a partial 5-HT1A receptor agonist, but not by fluoxetine, a selective serotonin reuptake inhibitor. The anxiety-like behavior induced by doxorubicin and cyclophosphamide combination treatment is mediated by hyperfunctioning of the 5-HT2A receptor. Thus, 5-HT2A receptor antagonists or 5-HT1A receptor agonists might be useful for treating chemotherapy-induced anxiety disorders.

DOI： 10.1016/j.jphs.2018.10.001

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Other Link： http://orcid.org/0000-0002-3652-3722

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/1028415x.2016.1253171

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DOI： 10.1007/s00210-016-1338-z

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DOI： 10.1186/s12868-016-0289-0

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Other Link： http://link.springer.com/article/10.1186/s12868-016-0289-0/fulltext.html

Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER HEIDELBERG  

In previous studies, we detected the photoinitiators 1-hydroxycyclohexyl phenyl ketone (1-HCHPK) and 2-methyl-4'-(methylthio)-2-morpholinopropiophenone (MTMP) in an intravenous injection solution. Importantly, 1-HCHPK and MTMP have been demonstrated to be cytotoxic to normal human peripheral blood (PB) mononuclear cells (MNC). Cell death (apoptosis) pathways can be classified into two modes, caspase-dependent and -independent pathways. However, it is unclear whether methyl 2-benzoylbenzoate (MBB) induces the caspase-dependent and/or -independent pathway in normal human PBMNC. In the present in vitro study, we examined the levels of MBB in a solution from an intravenous fluid bag and the cytotoxicity of MBB towards normal human PBMNC via the caspase-8-, caspase-9-, or apoptosis-inducing factor (AIF)-mediated apoptosis pathways. We found that extracts from the injection solution had been contaminated with approximately 80 mu M of the photoinitiator MBB. In addition, MBB induced apoptosis in the high concentration range in normal human PBMNC in vitro. Moreover, we found that MBB-induced apoptosis occurs via the caspase-9 pathway, but not the AIF pathway. In conclusion, we suggest that MBB has cytotoxic effects on normal human PBMNC in vitro, which are mediated via the caspase-dependent pathway.

DOI： 10.1007/s11356-016-6332-y

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

The high mobility group box-1 (HMGB1) exists as an architectural nuclear protein in the normal state, but displays an inflammatory cytokine-like activity in the extracellular space under pathological condition. Inflammation in the pathogenesis of Parkinson's disease (PD) has been documented. In this study, we investigated the involvement of HMGB1 in the pathology and the neuroprotective effects of neutralizing anti-HMGB1 monoclonal antibody (mAb) on an animal model of PD. Adult female Sprague-Dawley rats were initially injected with 6-hydroxydopmaine (6-OHDA, 20 mu g/4 mu l) into the right striatum, then anti-HMGB1 mAb (1 mg/kg), or control mAb was intravenously administered immediately, at 6 and 24 h after 6-OHDA injection. The treatment with anti-HMGB1 mAb significantly preserved dopaminergic neurons in substantia nigra pars compacta and dopaminergic terminals inherent in the striatum, and attenuated PD behavioral symptoms compared to the control mAb-treated group. HMGB1 was retained in the nucleus of neurons and astrocytes by inhibiting the proinflammation-induced oxidative stress in the anti-HMGB1 mAb-treated group, whereas HMGB1 translocation was observed in neurons at 1 day and astrocytes at 7 days after 6-OHDA injection in the control mAb-treated group. Anti-HMGB1 mAb inhibited the activation of microglia, disruption of blood-brain-barrier (BBB), and the expression of inflammation cytokines such as IL-1 beta. and IL-6. These results suggested that HMGB1 released from neurons and astrocytes was at least partly involved in the mechanism and pathway of degeneration of dopaminergic neurons induced by 6-0HDA exposure. Intravenous administration of anti-HMGB1 mAb stands as a novel therapy for PD possibly acting through the suppression of neuroinflammation and the attenuation of disruption of BOB associated with the disease. (C) 2015 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.expneurol.2015.11.003

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Society for Hard Tissue Regenerative Biology  

DOI： 10.2485/jhtb.25.21

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Society for Free Radical Research Japan  

<p><span style="font-variant: small-caps;">l</span>-Theanine (γ-glutamylethylamide), a component of green tea, is considered to have regulatory and neuroprotective roles in the brain. The present study was designed to determine the effect of <span style="font-variant: small-caps;">l</span>-theanine on excess dopamine-induced neurotoxicity in both cell culture and animal experiments. The primary cultured mesencephalic neurons or co-cultures of mesencephalic neurons and striatal astrocytes were pretreated with <span style="font-variant: small-caps;">l</span>-theanine for 72 h, and then treated with excess dopamine for further 24 h. The cell viability of dopamine neurons and levels of glutathione were evaluated. Excess dopamine-induced neurotoxicity was significantly attenuated by 72 h preincubation with <span style="font-variant: small-caps;">l</span>-theanine in neuron-astrocyte co-cultures but not in neuron-rich cultures. Exposure to <span style="font-variant: small-caps;">l</span>-theanine increased the levels of glutathione in both astrocytes and glial conditioned medium. The glial conditioned medium from <span style="font-variant: small-caps;">l</span>-theanine-pretreated striatal astrocytes attenuated dopamine-induced neurotoxicity and quinoprotein formation in mesencephalic neurons. In addition, replacement of <span style="font-variant: small-caps;">l</span>-glutamate with <span style="font-variant: small-caps;">l</span>-theanine in an in vitro cell-free glutathione-synthesis system produced glutathione-like thiol compounds. Furthermore, <span style="font-variant: small-caps;">l</span>-theanine administration (4 mg/kg, p.o.) for 14 days significantly increased glutathione levels in the striatum of mice. The results suggest that <span style="font-variant: small-caps;">l</span>-theanine provides neuroprotection against oxidative stress-induced neuronal damage by humoral molecules released from astrocytes, probably including glutathione.</p>

DOI： 10.3164/jcbn.16-15

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Many patients who have received chemotherapy to treat cancer experience depressive- and anxiety-like symptoms or cognitive impairment. However, despite the evidence for this, the underlying mechanisms are still not understood. This study investigated behavioral and biochemical changes upon treatment with doxorubicin and cyclophosphamide, focusing on mental and cognitive systems, as well as neurogenesis in male rats. Doxorubicin (2 mg/kg), cyclophosphamide (50 mg/kg), and the combination of doxorubicin and cyclophosphamide were injected intraperitoneally once per week for 4 weeks. In particular, the co-administration of doxorubicin and cyclophosphamide produced anhedonia-like, anxiety-like, and spatial cognitive impairments in rats. It also reduced both the number of proliferating cells in the subgranular zone of the hippocampal dentate gyrus and their survival. Serum brain-derived neurotrophic factor (BDNF) levels were decreased along with chemotherapy-induced decreases in platelet levels. However, hippocampal BDNF levels and Bdnf mRNA levels were not decreased by this treatment. On the other hand, hippocampal cyclin D1 levels were significantly decreased by chemotherapy. These results suggest that the co-administration of doxorubicin and cyclophosphamide induces psychological and cognitive impairment, in addition to negatively affecting hippocampal neurogenesis, which may be related to hippocampal cyclin D1 levels, but not hippocampal BDNF levels. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.bbr.2015.06.007

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Parkinson's disease (PD) is a progressive neurodegenerative disease with motor and non-motor symptoms that precede the onset of motor symptoms. Rotenone is often used to induce PD-like pathology in the central nervous system (CNS) and enteric nervous system (ENS). However, there is little or no information on the temporal changes in other neural tissues and the spread of pathology throughout the entire body organs. Here, we recorded the serial immunohistochemical changes in neurons and glial cells of the striatum, substantia nigra (SN), olfactory bulb (OB), thoracic cord (ThC) and ascending colon (AC) induced by 1-, 3- and 6-week administration of rotenone (50 mg/kg/day) infused subcutaneously in C57BL mice using an osmotic pump. Rotenone exposure for 3 or 6 weeks caused neurodegeneration in the striatum, whereas neuronal damage was seen in the SN and OB only after 6 weeks. Moreover, rotenone induced neurodegeneration in the myenteric plexus of AC but not in ThC. Rotenone also activated glial cells before any apparent neurodegeneration in the CNS but not in the ENS. Our results demonstrated that subcutaneous administration of rotenone can cause progressive neurodegeneration in the OB and AC, in addition to the nigrostriatal pathway, and temporal differential glial activation, and that these changes do not spread retrogradely from OB or ENS to nigrostriatal pathway. The results suggested that the different vulnerability of neurons to the neurotoxic effects of rotenone administrated subcutaneously are due to glial activation in these neural tissues.

DOI： 10.1007/s11064-015-1577-2

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Language：Japanese  

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Other Link： http://search.jamas.or.jp/link/ui/2015129550

Language：English   Publisher：OKAYAMA UNIV MED SCHOOL  

In vertebrates, almost all somatic cells extend a single immotile cilium, referred to as a primary cilium. Increasing evidence suggests that primary cilia serve as cellular antennae in many types of tissues by sensing chemical or mechanical stimuli in the milieu surrounding the cells. In rodents an antibody to adenylyl cyclase 3 (AC3) has been widely used to label the primary cilia of neurons in vivo by immunostaining, whereas the lack of markers for the primary cilia of astrocytes has made it difficult to observe astrocytic primary cilia in vivo. Here, we obtained a visualization of astrocytic primary cilia in the mouse brain. In the somatosensory cortex, a large portion of neurons and astrocytes at postnatal day 10 (P10), and of neurons at P56 had AC3-positive primary cilia, whereas only approx. one-half of the astrocytes in the P56 mice carried primary cilia weakly positive for AC3. In contrast, the majority of astrocytes had ADP-ribosylation factor-like protein 13B (Arl13b)-positive primary cilia in the somatosensory cortex and other brain regions of P56 mice. The lengths of astrocytic primary cilia positive for Arl13b varied among the brain regions. Our data indicate that Arl13b is a noteworthy marker of astrocytic primary cilia in the brain.

DOI： 10.18926/AMO/53020

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

ObjectiveDevelopmental disorders including cognitive deficit, hyperkinetic disorder, and autistic behaviors are frequently comorbid in epileptic patients with SCN1A mutations. However, the mechanisms underlying these developmental disorders are poorly understood and treatments are currently unavailable. Using a rodent model with an Scn1a mutation, we aimed to elucidate the pathophysiologic basis and potential therapeutic treatments for developmental disorders stemming from Scn1a mutations.MethodsWe conducted behavioral analyses on rats with the N1417H-Scn1a mutation. With high-performance liquid chromatography, we measured dopamine and its metabolites in the frontal cortex, striatum, nucleus accumbens, and midbrain. Methylphenidate was administered intraperitoneally to examine its effects on developmental disorder-like behaviors and hyperthermia-induced seizures.ResultsBehavioral studies revealed that Scn1a-mutant rats had repetitive behavior, hyperactivity, anxiety-like behavior, spatial learning impairments, and motor imbalance. Dopamine levels in the striatum and nucleus accumbens in Scn1a-mutant rats were significantly lower than those in wild-type rats. In Scn1a-mutant rats, methylphenidate, by increasing dopamine levels in the synaptic cleft, improved hyperactivity, anxiety-like behavior, and spatial learning impairments. Surprisingly, methylphenidate also strongly suppressed hyperthermia-induced seizures.SignificanceDysfunction of the mesolimbic dopamine reward pathway may contribute to the hyperactivity and learning impairments in Scn1a-mutant rats. Methylphenidate was effective for treating hyperactivity, learning impairments, and hyperthermia-induced seizures. We propose that methylphenidate treatment may ameliorate not only developmental disorders but also epileptic seizures in patients with SCN1A mutations.

DOI： 10.1111/epi.12750

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Parkinson's disease (PD) is a neurodegenerative disease with motor symptoms as well as non-motor symptoms that precede the onset of motor symptoms. Mitochondrial complex I inhibitor, rotenone, has been widely used to reproduce PD pathology in the central nervous system (CNS) and enteric nervous system (ENS). We reported previously that metallothioneins (MTs) released from astrocytes can protect dopaminergic neurons against oxidative stress. The present study examined the changes in MT expression by chronic systemic rotenone administration in the striatum and colonic myenteric plexus of C57BL mice. In addition, we investigated the effects of MT depletion on rotenone-induced neurodegeneration in CNS and ENS using MT-1 and MT-2 knockout (MT KO) mice, or using primary cultured neurons from MT KO mice. In normal C57BL mice, subcutaneous administration of rotenone for 6 weeks caused neurodegeneration, increased MT expression with astrocytes activation in the striatum and myenteric plexus. MT KO mice showed more severe myenteric neuronal damage by rotenone administration after 4 weeks than wild-type mice, accompanied by reduced astroglial activation. In primary cultured mesencephalic neurons from MT KO mice, rotenone exposure induced neurotoxicity in dopaminergic neurons, which was complemented by addition of recombinant protein. The present results suggest that MT seems to provide protection against neurodegeneration in ENS of rotenone-induced PD model mice.

DOI： 10.1007/s12640-014-9480-1

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L-DOPA is therapeutically efficacious in patients with Parkinson's disease (PD), although dopamine (DA) neurons are severely degenerated. Since cortical astrocytes express neutral amino acid transporter (LAT) and DA transporter (DAT), the uptake and metabolism of L-DOPA and DA in striatal astrocytes may influence their availability in the dopaminergic system of PD. To assess possible L-DOPA-and DA-uptake and metabolic properties of striatal astrocytes, we examined the expression of L-DOPA, DA and DAT in striatal astrocytes of hemi-parkinsonian model rats after repeated L-DOPA administration, and measured the contents of L-DOPA, DA and their metabolite in primary cultured striatal astrocytes after L-DOPA/DA treatment. Repeated injections of L-DOPA induced apparent L-DOPA-and DA-immunoreactivities and marked expression of DAT in reactive astrocytes on the lesioned side of the striatum in hemi-parkinsonian rats. Exposure to DA for 4 h significantly increased the levels of DA and its metabolite DOPAC in cultured striatal astrocytes. L-DOPA was also markedly increased in cultured striatal astrocytes after 4-h L-DOPA exposure, but DA was not detected 4 or 8 h after L-DOPA treatment, despite the expression of aromatic amino acid decarboxylase in astrocytes. Furthermore, the intracellular level of L-DOPA in cultured striatal astrocytes decreased rapidly after removal of extracellular L-DOPA. The results suggest that DA uptaken into striatal astrocytes is rapidly metabolized and that striatal astrocytes act as a reservoir of L-DOPA that govern the uptake or release of L-DOPA depending on extracellular L-DOPA concentration, but are less capable of converting L-DOPA to DA.

DOI： 10.1371/journal.pone.0106362

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

In the present study, we examined the effect of ACTH on the immobilization of rats in the forced swim test and hippocampal cell proliferation after administration of the 5-HT1A receptor agonist, R-(+)-8-hydroxy-2-di-n-propylamino tetralin ((+)-8-OH-DPAT). Chronic treatment with (+)-8-OH-DPAT (0.01-0.1 mg/kg, s.c.) significantly decreased the duration of immobility in saline- and ACTH-treated rats. Chronic administration of ACTH caused a significant decrease in hippocampal cell proliferation. However, (+)-8-OH-DPAT significantly normalized cell proliferation in ACTH-treated rats. We then investigated the effects of (+)-8-OH-DPAT on the expression of brain-derived neurotrophic factor (BDNF) and cyclin D1 (elements of cyclic adenosine monophosphate response element-binding protein (CREB)-BDNF and Wnt signaling pathways, respectively) in the hippocampus of saline- and ACTH-treated rats. ACTH treatment significantly decreased the expression of cyclin D1, while treatment with (+)-8-OH-DPAT normalized the expression of cyclin D1 in ACTH-treated rats. However, the expression of BDNF did not change in either saline- or ACTH-treated rats. These findings suggest that the antidepressant effects of (+)-8-OH-DPAT in treatment-resistant animals may be attributed to an enhancement of hippocampal cell proliferation, at least in part due to an enhancement of cyclin D1 expression. (C) 2014 Elsevier Inc All rights reserved.

DOI： 10.1016/j.pbb.2014.04.003

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In the rodent brain, certain G protein-coupled receptors and adenylyl cyclase type 3 are known to localize to the neuronal primary cilium, a primitive sensory organelle protruding singly from almost all neurons. A recent chemical screening study demonstrated that many compounds targeting dopamine receptors regulate the assembly of Chlamydomonas reinhardtii flagella, structures which are analogous to vertebrate cilia. Here we investigated the effects of dopaminergic inputs loss on the architecture of neuronal primary cilia in the rodent striatum, a brain region that receives major dopaminergic projections from the midbrain. We first analyzed the lengths of neuronal cilia in the dorsolateral striatum of hemi-parkinsonian rats with unilateral lesions of the nigrostriatal dopamine pathway. In these rats, the striatal neuronal cilia were significantly longer on the lesioned side than on the non-lesioned side. In mice, the repeated injection of reserpine, a dopamine-depleting agent, elongated neuronal cilia in the striatum. The combined administration of agonists for dopamine receptor type 2 (D2) with reserpine attenuated the elongation of striatal neuronal cilia. Repeated treatment with an antagonist of D2, but not of dopamine receptor type 1 (D1), elongated the striatal neuronal cilia. In addition, D2-null mice displayed longer neuronal cilia in the striatum compared to wild-type controls. Reserpine treatment elongated the striatal neuronal cilia in D1-null mice but not in D2-null mice. Repeated treatment with a D2 agonist suppressed the elongation of striatal neuronal cilia on the lesioned side of hemi-parkinsonian rats. These results suggest that the elongation of striatal neuronal cilia following the lack of dopaminergic inputs is attributable to the absence of dopaminergic transmission via D2 receptors. Our results provide the first evidence that the length of neuronal cilia can be modified by the lack of a neurotransmitter's input.

DOI： 10.1371/journal.pone.0097918

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPANESE PHARMACOLOGICAL SOC  

The specific toxicity to dopaminergic neurons of psychostimulants and neurotoxins has been extensively studied in vivo and in vitro, and findings have been used to establish animal models of amphetamine psychosis or Parkinson's disease. The multiple mechanisms of neurotoxicity operating in these disorders are known to involve oxidative stress or neuroinflammation, producing the characteristic behavioral and neuropathlogical changes arising from injured dopaminergic neurons and glial cells. A number of studies have shown that glia-targeting antioxidants play important roles in protecting against the neurotoxicity caused by psychostimulants or neurotoxins. Phytochemicals, which are non-nutritive plant chemicals, protect dopaminergic neurons and glial cells from damage caused by psychostimulants or neurotoxins. The objective of this review was to evaluate the involvement of glial cells in dopaminergic neuron specific toxicity and to explore the neuroprotective activity of phytochemicals in terms of anti-inflammatory and antioxidant action.

DOI： 10.1254/jphs.13R19CP

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The dopamine reuptake inhibitor bupropion and dopamine D2/3 receptor agonist pramipexole have been clinically proven to improve both depression and treatment-resistant depression. We examined its influence on the duration of immobility during the forced swim test in adrenocorticotropic hormone (ACTH)-treated rats and further analyzed the possible role of the dopamine nerve system in this effect. Bupropion and pramipexole significantly decreased the duration of immobility in normal and ACTH-treated rats. We previously demonstrated that the chronic administration of ACTH caused a significant decrease in hippocampal cell proliferation and neurogenesis. In this study, we used the mitotic marker 5-bromo-2'-deoxyridine to investigate the effects of bupropion and pramipexole on cell proliferation in the subgranular zone of the hippocampal dentate gyms following chronic treatment with ACTH. The ACTH treatment for 14 d decreased adult hippocampal cell proliferation. The chronic administration of bupropion for 14 d blocked the loss of cell proliferation resulting from the chronic treatment with ACTH, whereas pramipexole did not. The administration of bupropion may have treatment-resistant antidepressive properties, which may be partly attributed to the normalization of hippocampal cell proliferation.

DOI： 10.1248/bpb.b13-00749

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER PHYSIOLOGICAL SOC  

Oxidative stress and inflammation play important roles in diabetic complications, including diabetic nephropathy. Metallothionein (MT) is induced in proximal tubular epithelial cells as an antioxidant in the diabetic kidney; however, the role of MT in renal function remains unclear. We therefore investigated whether MT deficiency accelerates diabetic nephropathy through oxidative stress and inflammation. Diabetes was induced by streptozotocin injection in MT-deficient (MT-/-) and MT+/+ mice. Urinary albumin excretion, histological changes, markers for reactive oxygen species (ROS), and kidney inflammation were measured. Murine proximal tubular epithelial (mProx24) cells were used to further elucidate the role of MT under high-glucose conditions. Parameters of diabetic nephropathy and markers of ROS and inflammation were accelerated in diabetic MT-/- mice compared with diabetic MT+/+ mice, despite equivalent levels of hyperglycemia. MT deficiency accelerated interstitial fibrosis and macrophage infiltration into the interstitium in the diabetic kidney. Electron microscopy revealed abnormal mitochondrial morphology in proximal tubular epithelial cells in diabetic MT-/- mice. In vitro studies demonstrated that knockdown of MT by small interfering RNA enhanced mitochondrial ROS generation and inflammation-related gene expression in mProx24 cells cultured under high-glucose conditions. The results of this study suggest that MT may play a key role in protecting the kidney against high glucose-induced ROS and subsequent inflammation in diabetic nephropathy.

DOI： 10.1152/ajprenal.00034.2013

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Tyrosinase, which catalyzes both the hydroxylation of tyrosine and consequent oxidation of L-DOPA to form melanin in melanocytes, is also expressed in the brain, and oxidizes L-DOPA and dopamine. Replacement of dopamine synthesis by tyrosinase was reported in tyrosine hydroxylase null mice. To examine the potential benefits of autograft cell transplantation for patients with Parkinson's disease, tyrosinase-producing cells including melanocytes, were transplanted into the striatum of hemi-parkinsonian model rats or mice lesioned with 6-hydroxydopamine. Marked improvement in apomorphine-induced rotation was noted at day 40 after intrastriatal melanoma cell transplantation. Transplantation of tyrosinase cDNA-transfected hepatoma cells, which constitutively produce L-DOPA, resulted in marked amelioration of the asymmetric apomorphine-induced rotation in hemi-parkinsonian mice and the effect was present up to 2 months. Moreover, parkinsonian mice transplanted with melanocytes from the back skin of black newborn mice, but not from albino mice, showed marked improvement in the apomorphine-induced rotation behavior up to 3 months after the transplantation. Dopamine-positive signals were seen around the surviving transplants in these experiments. Taken together with previous studies showing dopamine synthesis and metabolism by tyrosinase, these results highlight therapeutic potential of intrastriatal autograft cell transplantation of melanocytes in patients with Parkinson's disease. © 2013 Asanuma et al.

DOI： 10.1371/journal.pone.0065983

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Aims Cisplatin (CDDP) is a potent anticancer agent, but severe renal toxicity can limit its use. We investigated the protective effect of cepharanthin (CE), a biscoclaurin alkaloid, on the renal toxicity of CDDP. Main methods Mice were given CDDP along with CE. Effects of CE on CDDP toxicity were investigated by assaying markers of renal toxicity together with MT expression, and by histopathological examination of the kidney. MT-null mice were also examined. Key findings CE induced expression of metallothionein (MT). Pre-administration of CE attenuated an increase in blood urea nitrogen (BUN) concentrations after the CDDP injection. A histochemical analysis demonstrated protection against CDDP-induced necrocytosis of kidney tissues by CE. The protective effect of CE did not occur in the MT-null mice. Significance Pretreatment with CE may reduce the renal toxicity of CDDP through expression of MT. © 2013 Elsevier Inc.

DOI： 10.1016/j.lfs.2013.01.031

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In clinical studies, electroconvulsive stimuli have been associated with improvements in both depression and treatment-resistant depression. In a previous study, treatment with adrenocorticotropic hormone (ACTH) for 14 days decreased adult hippocampal cell proliferation. Furthermore, electroconvulsive stimuli significantly decreased the duration of immobility following repeated administration of ACTH for 14 days in rats. The present study was undertaken to further characterize the mechanism of treatment-resistant antidepressant effects of electroconvulsive stimuli by measuring cell proliferation, brain-derived neurotrophic factor (BDNF) levels, and phosphorylated and total cyclic adenosine monophosphate (cAMP) response element-binding protein (pCREB/CREB) levels in the hippocampus of ACTH-treated rats. Electroconvulsive stimuli increased cell proliferation in both saline-treated and ACTH-treated rats. Mature-BDNF protein levels showed a tendency to decrease in ACTH-treated rats. Electroconvulsive stimuli treatment increased mature-BDNF protein levels in the hippocampus of both saline-treated and ACTH-treated rats. Furthermore, electroconvulsive stimuli increased phospho-Ser133-CREB (pCREB) levels and the ratio of pCREB/CREB in both saline-treated and ACTH-treated rats. These findings suggest that the treatment-resistant antidepressant effects of electroconvulsive stimuli may be attributed, at least in part, to an enhancement of hippocampal cell proliferation. © The Japanese Pharmacological Society.

DOI： 10.1254/jphs.13015FP

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.neurobiolaging.2011.11.014

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER/PLENUM PUBLISHERS  

Prostaglandin H synthase exerts not only cyclooxygenase activity but also peroxidase activity. The latter activity of the enzyme is thought to couple with oxidation of dopamine to dopamine quinone. Therefore, it has been proposed that cyclooxygenase inhibitors could suppress dopamine quinone formation. In the present study, we examined effects of various cyclooxygenase inhibitors against excess methyl L-3,4-dihydroxyphenylalanine (L-DOPA)-induced quinoprotein (protein-bound quinone) formation and neurotoxicity using dopaminergic CATH.a cells. The treatment with aspirin inhibited excess methyl L-DOPA-induced quinoprotein formation and cell death. However, acetaminophen did not show protective effects, and indomethacin and meloxicam rather aggravated these methyl L-DOPA-induced changes. Aspirin and indomethacin did not affect the level of glutathione that exerts quenching dopamine quinone in dopaminergic cells. In contrast with inhibiting effects of higher dose in the previous reports, relatively lower dose of aspirin that affected methyl L-DOPA-induced quinoprotein formation and cell death failed to prevent cyclooxygenase-induced dopamine chrome generation in cell-free system. Furthermore, aspirin but not acetaminophen or meloxicam showed direct dopamine quinone-scavenging effects in dopamine-semiquinone generating systems. The present results suggest that cyclooxygenase shows little contribution to dopamine oxidation in dopaminergic cells and that protective effects of aspirin against methyl L-DOPA-induced dopamine quinone neurotoxicity are based on its cyclooxygenase-independent property.

DOI： 10.1007/s11064-012-0813-2

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MULTIMED INC  

Objective: Residual renal function (RRF) is associated with low oxidative stress in peritoneal dialysis (PD). In the present study, we investigated the relationship between the impact of oxidative stress on RRF and patient outcomes during PD.
Methods: Levels of free radicals (FRs) in effluent from the overnight dwell in 45 outpatients were determined by electron spin resonance spectrometry. The FR levels, clinical parameters, and the level of 8-hydroxy-2'-deoxyguanosine were evaluated at study start. The effects of effluent FR level on technique and patient survival were analyzed in a prospective cohort followed for 24 months.
Results: Levels of effluent FRs showed significant negative correlations with daily urine volume and residual renal Kt/V, and positive correlations with plasma beta(2)-microglobulin and effluent 8-hydroxy-2'-deoxyguanosine. A highly significant difference in technique survival (p &lt; 0.05), but not patient survival, was observed for patients grouped by effluent FR quartile. The effluent FR level was independently associated with technique failure after adjusting for patient age, history of cardiovascular disease, and presence of diabetes mellitus (p &lt; 0.001). The level of effluent FRs was associated with death-censored technique failure in both univariate (p &lt; 0.001) and multivariate (p &lt; 0.01) hazard models. Compared with patients remaining on PD, those withdrawn from the modality had significantly higher levels of effluent FRs (p &lt; 0.005).
Conclusions: Elevated effluent FRs are associated with RRF and technique failure in stable PD patients. These findings highlight the importance of oxidative stress as an unfavorable prognostic factor in PD and emphasize that steps should be taken to minimize oxidative stress in these patients. Perit Dial Int 2012; 32(4): 453-461

DOI： 10.3747/pdi.2011.00032

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DOI： 10.1248/yakushi.132.173

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MANEY PUBLISHING  

Objectives: Baicalein, a flavonoid derived from the root of Scutelaria baicalensis Georgi, possesses antioxidative properties including reactive oxygen species scavenging and lipid peroxidation inhibiting activities. The present study was undertaken to investigate the neuroprotective effect of baicalein against dopamine (DA) neurotoxicity induced by exposure to a synthetic DA precursor, L-3,4-dihydroxyphenylalanine (L-DOPA), in cultured dopaminergic CATH. a cells.
Methods and results: Exposure to L-DOPA for 24 hours reduced the number of viable cells and enhanced protein-bound quinone (quinoprotein) formation in the cell. Both effects were prevented by simultaneous treatment with baicalein. In addition, baicalein prevented the formation of DA semiquinone radicals from DA in an in vitro cell-free system. Long-term baicalein treatment for 96 hours also protected against excess L-DOPA-induced cell death, and also increased glutathione (GSH) levels in CATH. a cells.
Discussion: Our results indicate that baicalein has neuroprotective properties against excess L-DOPA-induced DA neurotoxicity through the suppression of DA quinone formation. Furthermore, the long-term treatment of baicalein upregulates intracellular GSH contents, which may also exert neuroprotective effects against oxidative stress-induced neuronal damage.

DOI： 10.1179/1743132811Y.0000000032

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Language：English   Publisher：OKAYAMA UNIV MED SCHOOL  

Almost all mammalian cells carry one primary cilium that functions as a biosensor for chemical and mechanical stimuli. Genetic damages that compromise cilia formation or function cause a spectrum of disorders referred to as ciliapathies. Recent studies have demonstrated that some pharmacological agents and extracellular environmental changes can alter primary cilium length. Renal injury is a well-known example of an environmental insult that triggers cilia length modification. Lithium treatment causes primary cilia to extend in several cell types including neuronal cells; this phenomenon is likely independent of glycogen synthase kinase-3 beta inhibition. In renal epithelial cell lines, deflection of the primary cilia by fluid shear shortens them by reducing the intracellular cyclic AMP level, leading to a subsequent decrease in mechanosensitivity to fluid shear. Primary cilium length is also influenced by the dynamics of actin filaments and microtubules through the levels of soluble tubulin in the cytosol available for primary cilia extension. Thus, mammalian cells can adapt to the extracellular environment by modulating the primary cilium length, and this feedback system utilizing primary cilia might exist throughout the mammalian body. Further investigation is required concerning the precise molecular mechanisms underlying the control of primary cilium length in response to environmental factors.

DOI： 10.18926/AMO/47009

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Language：English   Publisher：WILEY-BLACKWELL  

DOI： 10.1002/ana.22347

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PHARMACEUTICAL SOC JAPAN  

Adult hippocampal neurogenesis is reported to change in animal models of depression and antidepressants. We have used the mitotic marker 5-bromo-2'-deoxyyridine to address the effects of imipramine and lithium on cell proliferation and survival following chronic treatment with adrenocorticotropic hormone (ACTH) in the subgranular zone of the hippocampal dentate gyrus. ACTH treatment for 14d decreased adult hippocampal cell proliferation and survival. Coadministration of imipramine and lithium for 14d blocked the loss of cell proliferation but not cell survival resulting from the chronic treatment with ACTH. The coadministration of imipramine and lithium may have treatment-resistant antidepressive properties, which may be attributed, in part, to a normalization of hippocampal cell proliferation.

DOI： 10.1248/bpb.34.77

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Hindawi Limited  

Metallothionein (MT) is an intracellular metal-binding, cysteine-rich protein, and is a potent antioxidant that protects cells and tissues from oxidative stress. Although the major isoforms MT-1 and -2 (MT-1/-2) are highly inducible in many tissues, the distribution and role of MT-1/-2 in diabetic nephropathy are poorly understood. In this study, diabetes was induced in adult male rats by streptozotocin, and renal tissues were stained with antibodies for MT-1/-2. MT-1/-2 expression was also evaluated in mProx24 cells, a mouse renal proximal tubular epithelial cell line, stimulated with high glucose medium and pretreated with the antioxidant vitamin E. MT-1/-2 expression was gradually and dramatically increased, mainly in the proximal tubular epithelial cells and to a lesser extent in the podocytes in diabetic rats, but was hardly observed in control rats. MT-1/-2 expression was also increased by high glucose stimulation in mProx24 cells. Because the induction of MT was suppressed by pretreatment with vitamin E, the expression of MT-1/-2 is induced, at least in part, by high glucose-induced oxidative stress. These observations suggest that MT-1/-2 is induced in renal proximal tubular epithelial cells as an antioxidant to protect the kidney from oxidative stress, and may offer a novel therapeutic target against diabetic nephropathy.

DOI： 10.1155/2011/534872

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Other Link： http://downloads.hindawi.com/journals/jdr/2011/534872.xml

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OKAYAMA UNIV MED SCHOOL  

We examined the influence of chronic adrenocorticotropic hormone (ACTH) treatment on the number of Ki-67-positive cells in the dentate gyrus of the hippocampus in rats. ACTH treatment for 14 days decreased the number of such cells. The administration of imipramine or lithium alone for 14 days had no effect in saline-treated rats. The effect of ACTH was blocked by the administration of imipramine. Furthermore, the coadministration of imipramine and lithium for 14 days significantly increased the number of Ki-67-positive cells in both the saline and ACTH-treated rats. The coadministration of imipramine and lithium normalized the cell proliferation in the dentate gyrus of the hippocampus in rats treated with ACTH.

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Language：English   Publishing type：Part of collection (book)   Publisher：Nova Science Publishers, Inc.  

Metallothioneins (MTs) are a family of low molecular weight, cysteine-rich, ubiquitous, and inducible intracellular proteins that bind to heavy metals such as zinc, copper, and cadmium, participating in metal homeostasis and detoxification. The mammalian MT family comprises four isoforms: MT-1, MT-2, MT-3, and MT-4. The two major isoforms, MT-1 and-2, are expressed in most organs including the brain. MT-1 and-2 help to regulate metal homeostasis in the brain, as well as neural protective functions in various pathological and inflammatory conditions. MT-3, called growth inhibitory factor, is mainly expressed in the central nervous system and decreased in the brain of Alzheimer's disease. Attention has been focused on MTs as radical scavengers because of their abundant thiol groups, which participate exclusively in the formation of metal-thiolate clusters. The reactive oxygen or nitrogen species (ROS/RNS), generated in the oxidation of an excess amount of dopamine (DA), is thought to play an important role in dopaminergic neurotoxicity. In contrast to the general oxidative stress, the pathogenecity of quinone formation has been recently received attention as dopaminergic neuron-specific oxidative stress. When the DA neurons are damaged, an excess amount of cytosolic DA exists outside of the synaptic vesicle is spontaneously oxidized and produces superoxide and DA/DOPA quinones. DA quinone conjugates with cysteine-residues on functional proteins to form quinoproteins. Therefore, intrinsic thiol molecule MTs could be a therapeutic tool against dopaminergic neurotoxicity to prevent DA quinone from binding to the sulfhydryl groups of cysteine on functional proteins by their conjugation with DA quinone. Indeed, our recent study showed that MT exerts protective effects against the long-term L-DOPA treatment-induced DA quinone neurotoxicity in parkinsonian mice by its quenching property of DA quinone. In this article, we primarily review recent studies from our and other groups on the antioxidative and neuroprotective roles of MTs against oxidative stress including DA quinone neurotoxicity in dopaminergic neurons. © 2010 by Nova Science Publishers, Inc. All rights reserved.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：FEDERATION AMER SOC EXP BIOL  

The Drosophila pericentrin-like protein has been shown to be essential for the formation of the sensory cilia of chemosensory and mechanosensory neurons by mutant analysis in flies, while the in vivo function of pericentrin, a well-studied mammalian centrosomal protein related to microcephalic primordial dwarfism, has been unclear. To determine whether pericentrin is required for ciliogenesis in mammals, we generated and analyzed mice with a hypomorphic mutation of Pcnt encoding the mouse pericentrin. Immunofluorescence analysis demonstrated that olfactory cilia of chemosensory neurons in the nasal olfactory epithelium were malformed in the homozygous mutant mice. On the other hand, the assembly of motile and primary cilia of non-neuronal epithelial cells and the formation of sperm flagella were not affected in the Pcnt-mutant mice. The defective assembly of olfactory cilia in the mutant was apparent from birth. The mutant animals displayed reduced olfactory performance in agreement with the compromised assembly of olfactory cilia. Our findings suggest that pericentrin is essential for the assembly of chemosensory cilia of olfactory receptor neurons, but it is not globally required for cilia formation in mammals.-Miyoshi, K., Kasahara, K., Miyazaki, I., Shimizu, S., Taniguchi, M., Matsuzaki, S., Tohyama, M., Asanuma, M. Pericentrin, a centrosomal protein related to microcephalic primordial dwarfism, is required for olfactory cilia assembly in mice. FASEB J. 23, 3289-3297 ( 2009). www.fasebj.org

DOI： 10.1096/fj.08-124420

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

The molecular mechanisms underlying the therapeutic effects of lithium, a first-line antimanic mood stabilizer, have not yet been fully elucidated. Treatment of the algae Chlamydomonas reinhardtii with lithium has been shown to induce elongation of their flagella, which are analogous structures to vertebrate cilia. In the mouse brain, adenylyl cyclase 3 (AC3) and certain neuropeptide receptors colocalize to the primary cilium of neuronal cells, suggesting a chemosensory function for the primary cilium in the nervous system. Here we show that lithium treatment elongates primary cilia in the mouse brain and in cultured cells. Brain sections from mice chronically fed with Li(2)CO(3) were subjected to immunofluorescence study. Primary cilia carrying both AC3 and the receptor for melanin-concentrating hormone (MCH) were elongated in the dorsal striatum and nucleus accumbens of lithium-fed mice, as compared to those of control animals. Moreover, lithium-treated NIH3T3 cells and cultured striatal neurons exhibited elongation of the primary cilia. The present results provide initial evidence that a psychotropic agent can affect ciliary length in the central nervous system, and furthermore suggest that lithium exerts its therapeutic effects via the upregulation of cilia-mediated MCH sensing. These findings thus contribute novel insights into the pathophysiology of bipolar mood disorder and other psychiatric diseases. (C) 2009 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.bbrc.2009.08.099

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER/PLENUM PUBLISHERS  

We examined changes in nuclear peroxisome proliferator-activated receptor gamma (PPAR gamma) in the striatum in methamphetamine (METH)-induced dopaminergic neurotoxicity, and also examined effects of treatment with drugs possessing PPAR gamma agonistic properties. The marked reduction of nuclear PPAR gamma-expressed cells was seen in the striatum 3 days after METH injections (4 mg/kg x 4, i.p. with 2-h interval). The reduction of dopamine transporter (DAT)-positive signals and PPAR gamma expression, and accumulation of activated microglial cells were significantly and dose-dependently attenuated by four injections of a nonsteroidal anti-inflammatory drug and a PPAR gamma ligand, ibuprofen (10 or 20 mg/kg x 4, s.c.) given 30 min prior to each METH injection, but not by either a low or high dose of aspirin. Either treatment of ibuprofen or aspirin, that showed no effects on METH-induced hyperthermia, significantly blocked the METH-induced striatal cyclooxygenase (COX) expression. Furthermore, the treatment of an intrinsic PPAR gamma ligand 15d-PG J2 also attenuated METH injections-induced reduction of striatal DAT. Therefore, the present study suggests the involvement of reduction of PPAR gamma expression in METH-induced neurotoxicity. Taken together with the previous report showing protective effects of other PPAR gamma ligand, these results imply that the protective effects of ibuprofen against METH-induced neurotoxicity may be based, in part, on its anti-inflammatory PPAR gamma agonistic properties, but not on its COX-inhibiting property or hypothermic effect.

DOI： 10.1007/s11064-008-9863-x

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Language：English   Publishing type：Part of collection (book)   Publisher：ELSEVIER ACADEMIC PRESS INC  

DOI： 10.1016/S0074-7742(09)88003-3

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

Aggregation of proteins in the centrosome is implicated in the pathophysiology of Parkinson&apos;s disease. However, the relevance of the centrosome in neurodegeneration is still obscure. Centrosome duplication is initiated by the cyclin E/cyclin-dependent kinase 2 (Cdk2) complex. The present study determined changes in cyclin E or Cdk2 expression and in the centrosomal structure in dopaminergic neuronal CATH.a cells exposed to 50, 100 and 150 mu M dopamine (DA) for 24 h. DA induced significant increase in Cdk2 protein and cyclin E protein, but not cyclin a mRNA. In DA-treated cells, the intense cyclin E- and Cdk2-immunofluorescence signals were co-localized around large and supernumerary centrosomes, and these two parameters of centrosome amplification were significantly increased compared with the control. Simultaneous co-treatment with DA and a Cdk2 inhibitor blocked centrosome amplification and enhanced cell viability. Our results demonstrated that DA could lead to cyclin E accumulation and Cdk2 up-regulation triggering supernumerary centrosomes and apoptotic cell death.

DOI： 10.1007/BF03033854

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DOI： 10.1016/j.toxlet.2008.06.864

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPANESE CIRCULATION SOC  

Background Coronary ischemia-reperfusion (I/R) injury causes cardiomyocyte necrosis in a multi-step process that includes an inflammatory reaction. A recent study has suggested that high-mobility group box 1 (HMGB 1) is a late mediator of lethal sepsis and an early mediator of inflammation and necrosis following I/R injury. In the present study a neutralizing monoclonal antibody (mAb) for HMGB1 was used to clarify the role of HMGB 1 in cardiac I/R injury.
Methods and Results Rats underwent 30 min of left coronary artery occlusion followed by 60 min reperfusion. An intravenous injection of anti-HMGB1 mAb or control IgG was administered just before reperfusion. The infarct size was enlarged in the anti-HMGB1 mAb group in comparison with the control group (p&lt;0.05). The treatment of anti-HMGB1 mAb significantly increased the plasma troponin-T and norepinephrine (NE) content in the heart in comparison with the control (p&lt;0.05). Moreover, the production of dihydroxyphenylglycol was reduced in the anti-HMGB1-treated group (p&lt;0.05).
Conclusion This study shows for the first time the effects of treatment with neutralizing anti-HMGB1 mAb on I/R injury in the rat heart. The findings support the novel view that I/R-induced HMGB1 may be an important factor in the modulation of interstitial NE.

DOI： 10.1253/circj.72.1178

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Language：English   Publisher：BENTHAM SCIENCE PUBL LTD  

A number of experimental studies using parkinsonian models have revealed that nonsteroidal anti-inflammatory drugs (NSAIDs) have neuroprotective properties against dopaminergic neurotoxicity not only by their cyclooxygenase-inhibiting effect but also by other specific properties or some unknown pharmacological effects. This article reviews heterogeneous pharmacological properties of NSAIDs including inhibitory effect against nitric oxide synthesis, agonistic action for peroxisome proliferator-activated receptor or possible suppressive effects against dopamine quinone generation, and also reviews their neuroprotective effects in the experimental parkinsonian models and pathogenesis of Parkinson's disease. Several epidemiological studies recently clarified that the use of nonaspirin NSAIDs but not aspirin was associated with a lower prevalence of Parkinson's disease, in contrast with neuroprotective effects of aspirin in the experimental studies. It also discusses the discrepancy between results in the experimental parkinsonian models and epidemiological data in prevalence of Parkinson's disease on the effects of NSAIDs.

DOI： 10.2174/138161208784480153

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER IRELAND LTD  

We identified p53-activated gene 608 (PAG608) as a specifically induced gene in striatal tissue of L-DOPA (100 mg/kg)-injected hemi-parkinsonian rats using differential display assay. In the present study, we further examined morphological distribution of PAG608 in the central nervous system of L-DOPA-treated hemi-parkinsonian rats. PAG608 expression was markedly induced in fibers and neuronal cells of the lateral globus pallidus and reticular thalamic nucleus adjacent to internal capsule, specifically in the parkinsonian side of L-DOPA-treated models. The protein was also constitutively expressed in motor neurons specifically in either side of the pontine nucleus and motor nuclei of trigeminal and facial nerves. Furthermore, L-DOPA-induced PAG608 expression on motor neurons in the contralateral side of the ventral horn of the spinal cord and the lateral corticospinal tract without cell loss. The specific induction of PAG608 6-48 h after L-DOPA injection in the extrapyramidal tracts, pyramidal tracts and corresponding lower motor neurons of the spinal cords suggests its involvement in molecular events in stimulated motor neurons. Taken together with the constitutive expression of PAG608 in the motor nuclei of cranial nerves, PAG608 may be a useful marker of stressed or activated lower motor neurons. (C) 2007 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

DOI： 10.1016/j.neures.2007.12.006

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER IRELAND LTD  

Repeated injections of methamphetamine (METH) cause degeneration of striatal dopaminergic nerve terminals. In the present study, we examined the effects of interferon-gamma (IFN-gamma) on METH-induced striatal neurotoxicity in mice. Intraperitoneal injection of IFN-gamma before METH injection significantly prevented METH-induced reduction of striatal dopamine transporter (DAT)-positive signals and hyperthermia. Furthermore, intracerebroventricular injection of IFN-gamma before METH treatment markedly prevented METH-induced reduction of DAT. Interestingly, central IFN-gamma injection had no effect on METH-induced hyperthermia. In addition, IFN-gamma injected centrally after METH treatment, but not systemically, 1 h after the final METH injection significantly protected against METH-induced neurotoxicity. Our results suggest that IFN-gamma injected systemically or its related molecule protects against METH-induced neurotoxicity through intracerebral molecular pathways, while it can prevent METH-induced hyperthermia through different molecular events. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

DOI： 10.1016/j.toxlet.2008.01.005

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：BLACKWELL PUBLISHING  

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The neurotoxicity of dopamine (DA) quinones as dopaminergic neuron-specific oxidative stress is considered to play a role in the pathogenesis and/or progression of Parkinson's disease (PD), since DA quinones conjugate with several key PD pathogenic molecules (e.g., tyrosine hydroxylase, alpha-synuclein and parkin) to form protein-bound quinone (quinoprotein) and consequently inhibit their functions. Zonisamide (ZNS) is used as an anti-epileptic agent but also improved the cardinal symptoms of PD in recent clinical trials in Japan. To evaluate the effects of ZNS on excess cytosolic free DA-induced quinone toxicity, we examined changes in DA quinone-related indices after ZNS treatment both in in vitro cell-free system and in cultured cells. Co-incubation of DA and ZNS in a cell-free system caused conversion of DA to stable melanin via formation of DA-semiquinone radicals and DA chrome. Long-term (5 days) treatment with ZNS decreased quinoprotein and increased DA/DOPA chromes in dopaminergic CATH.a cells. ZNS significantly inhibited quinoprotein formation induced by treatment with tetrahydrobiopterin and ketanserin that elevate cytosolic free DA in the cells. Our results suggest that the novel anti-parkinsonian agent ZNS possesses preventing effects against DA quinone formation induced by excess amount of cytosolic DA outside the synaptic vesicles. (c) 2007 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

DOI： 10.1016/j.neures.2007.10.002

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Language：Japanese   Publisher：Okayama Medical Association  

DOI： 10.4044/joma.119.235

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Other Link： http://ousar.lib.okayama-u.ac.jp/13216

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DOI： 10.1016/j.expneurol.2007.05.006

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The p53-activated gene 608 (PAG608) is a proapoptotic gene activated and regulated by p53 expression in oxidative stress-induced apoptosis of neuronal cells. In this study, we determined the role of PAG608 in methamphetamine-induced neurotoxicity. Treatment of mouse dopaminergic CATH.a cells with 2 mM methamphetamine increased PAG608 expression at 3 h followed by increase in phosphorylated p53 expression. Transient transfection of PAG608 antisense cDNA or RNA interference using PAG608 small interfering RNA significantly attenuated the dose-dependent decrease in cell viability of CATH.a cells by methamphetamine (1-4 mM) exposure. In monoaminergic neuronal B65 cells, which contain serotonin rather than dopamine, methamphetamine-induced cell death was also significantly but partially protected by transient transfection of PAG608 antisense cDNA. Furthermore, cell death of PC 12 cells produced by methamphetamine (1-5 mM) was almost completely prevented by stable expression of PAG608 antisense cDNA, compared with significant reduction of cell viability in control PC12 cells. Our results showed that suppression of PAG608 using transient and stable transfection with PAG608 anti sense cDNA or small interfering RNA attenuates methamphetamine-induced death of various monoaminergic neuronal cells, suggesting that methamphetamine neurotoxicity in monoaminergic cells is related, at least in part, to induction of PAG608 expression. (c) 2006 Elsevier Ireland Ltd. All rights reserved.

DOI： 10.1016/j.neulet.2006.12.036

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OKAYAMA UNIV MED SCHOOL  

We examined the involvement of the signal transducer and activator of transcription 3 (STAT3) in bladder outlet obstruction (BOO)-induced bladder smooth muscle hypertrophy using a rat in vivo and in vitro study. BOO induced increases in bladder weight and bladder smooth muscle thickness I week after the operation. By using antibody microarrays, 64 of 389 proteins blotted on the array met our selection criteria of an INR value between &gt;= 2.0 and &lt;= 0.5. This result revealed up-regulation of transcription factors, cell cycle regulatory proteins, apoptosis-associated proteins and so on. On the other hand, down-regulation (INR value &lt;= 0.5) of proteins was not found. In a profiling study, we found an increase in the expression of STAT3. A significant increase in nuclear phosphorylated STAT3 expression was confirmed in bladder smooth muscle tissue by immunohistochemistry and Western blot analysis. Cyclical stretch-relaxation (I Hz) at 120% elongation significantly increased the expression of STAT3 and of alpha-smooth muscle actin in primary cultured bladder smooth muscle cells. Furthermore, the blockade of STAT3 expression by the transfection of STAT3 small interfering RNA (siRNA) significantly prevented the stretch-induced increase in alpha-smooth muscle actin expression. These results suggest that STAT3 has an important role in the induction of bladder smooth muscle hypertrophy.

DOI： 10.18926/AMO/30724

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

Pericentrin was first identified as a mouse centrosomal protein and is now referred to as pericentrin A. A larger homologous protein in humans with a C-terminal calmodulin-binding domain was later identified as pericentrin B. Pericentrin has been shown to be one of the key components in ciliogenesis.. but in vivo pericentrin products have remained ambiguous. Here we characterized pericentrin isoforms in mice. Two pericentrin transcripts of 9.5 and 6.9 kb were recognized on the mouse tissue Northern blots, while a cRNA probe for a 5'-terminal sequence shared by pericentrin A and B failed to hybridize to the 6.9-kb message. Two pericentrin cDNAs were identified, which encoded pericentrin B and a novel isoform, pericentrin S, sharing with pericentrin B a C-terminal calmodulin-binding motif. Three pericentrin proteins of 360, 255, and 250 kDa revealed by immunoprecipitation analysis were thought to correspond to pericentrin B, pericentrin S, and an unknown N-terminal product. (c) 2006 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.bbrc.2006.10.101

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1586/14737175.6.9.1313

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Pericentrin (Pcnt) is a giant coiled-coil protein known to mediate microtubule organization. It has been recently reported that mitosis-specific centrosomal anchoring of gamma tubulin complexes by Pcnt acts to control mitotic spindle organization, though little is known about the in vivo expression of Pcnt. In this study, we investigated Pcnt expression in mouse embryos. In situ hybridization analysis revealed preferential expression of Pcnt in quiescent G(0) phase cells throughout the embryo with an unexpectedly low expression level in proliferating cells, suggesting that Pcnt might not play an important role in mitotic proliferation. Immunofluorescence analysis confirmed preferential expression of the Pcnt protein in G(0) phase cells. Moreover, Pcnt was shown to be localized to the base of primary cilia in multiple embryonic tissues, in agreement with a recent study demonstrating the involvement of Pcnt in primary cilia formation using cultured mammalian cells.

DOI： 10.1007/s00427-006-0065-8

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Recently, the formation of inclusion bodies in several neurodegenerative diseases, including Parkinson's disease, has been associated with the aggregation of unfolded proteins recruited in the centrosome. We have reported previously that rotenone, an insecticide that is used to produce experimental models of Parkinsonism, induced the aggregation of the alpha-synuclein protein in the centrosome, and it notably affected the structure and function of this organelle in primary cultures of mesencephalic neurons and astrocytes. However, it is still obscure the mechanisms through which the disorganization and centrosomal dysfunction could induce cell death. In this study the rat neuroblastoma B65 cell line was chronically exposed to rotenone, and then the distribution of the centrosomal protein gamma-tubulin was studied by immunocytochemistry and Western blot analyses. Finally, the configuration of mitotic spindles and distribution of the p53 protein was observed in the control and rotenone-treated groups. Rotenone treatment increased the number of cells having centrosome overduplication and multipolar mitotic spindles. In contrast, rotenone induced redistribution of the p53 protein, which was colocalized with the gamma-tubulin protein in the perinuclear region of cells having overduplicated centrosomes. In addition, the p53 positive signal was markedly intense in cells containing aberrant chromosome segregation and micronuclei. Our results suggest that centrosome overduplication may play an important role in the redistribution of the p53 protein in rotenone-treated cells, and this could represent an alternative mechanism of rotenone to induce apoptosis in neuronal cells.

DOI： 10.1111/j.1440-1819.2006.01526.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：DR DIETRICH STEINKOPFF VERLAG  

With regard to the mechanism of selective dopaminergic neuronal death, experimental results of studies on the neurotoxicity of MPTP and rotenone indicate that degeneration of dopamine neurons is closely related to mitochondrial dysfunction, inflammatory process and oxidative stress, particularly with regard to the generation of quinones as dopamine neuron-specific oxidative stress. Thus, it is now clear that the presence of high levels of discompartmentalized free dopamine in sdopaminergic neurons may explain the specific vulnerability of dopaminergic neurons through the generation of highly toxic quinones.

DOI： 10.1007/s00415-005-4006-7

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<bold>
<italic>Background—</italic>
</bold>
Idiopathic pulmonary arterial hypertension (IPAH) is associated with proliferation of smooth muscle cells (SMCs) in small pulmonary arteries. There is no therapy that specifically inhibits SMC proliferation. Recent studies reported that prednisolone (PSL) inhibits the postangioplasty proliferation of SMCs in atherosclerotic arteries. In this study, we tested the hypothesis that PSL has antiproliferative effects on pulmonary artery SMCs of patients with IPAH.




<bold>
<italic>Methods and Results—</italic>
</bold>
Pulmonary artery SMCs were harvested from the pulmonary arteries of 6 patients with IPAH who underwent lung transplantation. Control SMCs were obtained from 5 patients with bronchogenic carcinoma who underwent lung lobectomy. After incubation in the presence of platelet-derived growth factor (PDGF), PSL was added at different concentrations and cell proliferation was assessed by
³
H-thymidine incorporation. PSL (2×10
⁻⁴
and 2×10
⁻³
mol/L) significantly inhibited PDGF-stimulated proliferation (
<italic>P</italic>
&lt;0.05) of SMCs from patients with IPAH but did not affect cell viability of SMCs, as confirmed by trypan blue staining. In cell cycle analysis using a microscope-based multiparameter laser scanning cytometer, PSL inhibited the progression of SMCs from G
₀
/G
₁
to the S phase. This inhibition was associated with increased p27 expression level. PSL (2×10
⁻⁴
mol/L) also inhibited PDGF-induced SMC migration.




<bold>
<italic>Conclusions—</italic>
</bold>
Our results indicate that PSL has an antiproliferative effect on cultured SMCs of pulmonary arteries from patients with IPAH and suggest that PSL may be potentially useful therapeutically in patients with IPAH.

DOI： 10.1161/circulationaha.105.536169

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DOI： 10.1179/016164105x22093

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.neuroscience.2005.01.044

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Language：Japanese   Publisher：The Japanese Pharmacological Society  

DOI： 10.1254/fpj.126.30

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Language：English   Publisher：Okayama University Medical School  

DOI： 10.18926/AMO/32105

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1196/annals.1316.009

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1179/016164104225015895

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1111/j.1471-4159.2004.02445.x

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Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1111/j.1471-4159.2004.02445.x

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.bbrc.2004.03.163

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DOI： 10.1016/j.neulet.2003.09.059

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It is well known that nonsteroidal anti-inflammatory drugs (NSAIDs) possess anti-inflammatory, analgesic and antipyretic properties by inhibiting cyclooxygenase (COX), a prostaglandin-synthesizing enzyme. It has also been revealed that NSAIDs exert inhibitory effects on the generating system of nitric oxide radicals and modulating effects on transcription factors which are related to inflammatory reactions including cytokine expression. Recently, a number of studies have been conducted focusing on the neuroprotective effects of NSAIDs, since it has been reported that inflammatory processes are associated with the pathogenesis of several neurodegenerative diseases including Alzheimer's disease and Parkinson's disease. In the experimental model of Parkinson's disease, NSAIDs have also exerted neuroprotective effects which are based not only on their COX-inhibiting effects but also on other properties: inhibitory effects on nitric oxide synthesis, action as agonists for peroxisome proliferator-activated receptor gamma, and some unknown pharmacological effects. In this article, various pharmacological effects of NSAIDs except their inhibitory action on COX are reviewed, and possible neuroprotective effects of NSAIDs have been discussed on neurodegenerative diseases, especially Parkinson's disease.

DOI： 10.2174/1381612043453072

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Language：Japanese   Publisher：一般社団法人 日本泌尿器科学会  

DOI： 10.5980/jpnjurol.95.545_3

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DOI： 10.1016/j.neulet.2003.08.015

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DOI： 10.1016/s0168-0102(03)00166-4

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DOI： 10.1016/s0304-4165(02)00440-3

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Dopamine (DA)- or L-dihydroxyphenylalanine- (L-DOPA-) induced neurotoxicity is thought to be involved not only in adverse reactions induced by long-term L-DOPA therapy but also in the pathogenesis of Parkinson!s disease. Numerous in vitro and in vivo studies concerning DA- or L-DOPA-induced neurotoxicity have been reported in recent decades. The reactive oxygen or nitrogen species generated in the enzymatical oxidation or auto-oxidation of an excess amount of DA induce neuronal damage and/or apoptotic or non-apoptotic cell death; the DA-induced damage is prevented by various intrinsic and extrinsic antioxidants. DA and its metabolites containing two hydroxyl residues exert cytotoxicity in dopaminergic neuronal cells mainly due to the generation of highly reactive DA and DOPA quinones which are dopaminergic neuron-specific cytotoxic molecules. DA and DOPA quinones may irreversibly alter protein function through the formation of 5-cysteinyl-catechols on the proteins. For example, the formation of DA quinone-alpha-synuclein consequently increases cytotoxic protofibrils and the covalent modification of tyrosine hydroxylase by DA quinones. The melanin-synthetic enzyme tyrosinase in the brain may rapidly oxidize excess amounts of cytosolic DA and L-DOPA, thereby preventing slowly progressive cell damage by auto-oxidation of DA, thus maintaning DA levels. Since tyrosinase also possesses catecholamine-synthesizing activity in the absence of tyrosine hydroxylase (TH), the double-edged synthesizing and oxidizing functions of tyrosinase in the dopaminergic system suggest its potential for application in the synthesis of DA, instead of TH in the degeneration of dopaminergic neurons, and in the normalization of abnormal DA turnover in long-term L-DOPA-treated Parkinson's disease patients.

DOI： 10.1007/BF03033137

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1074/jbc.m203594200

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DOI： 10.1016/s0304-3940(02)00346-4

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DOI： 10.1016/s0168-0102(02)00040-8

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DOI： 10.1016/s0304-3940(02)00291-4

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DOI： 10.1016/s0304-3940(01)02547-2

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DOI： 10.1046/j.1471-4159.2000.0751771.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1023/a:1014967414468

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DOI： 10.1046/j.1471-4159.2001.00205.x

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DOI： 10.1016/s0168-0102(00)00233-9

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Language：English   Publisher：Okayama University Medical School  

DOI： 10.18926/AMO/32031

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1023/a:1007672414239

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DOI： 10.1016/s0006-8993(99)02284-2

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Recent information suggests that free radicals are closely involved in the pathogenesis and/or progression of Parkinson's disease (PD). High-dose levodopa therapy has been suggested to increase oxidative stress, thereby accelerating the progression of PD. Based on this viewpoint, free radical scavenging, antioxidant and neuroprotective agents which may prevent the progression of PD have recently attracted considerable attention. For example, ergot derivative dopamine (DA) agonists have been reported to scavenge free radicals in vitro and show a neuroprotective effect in vivo. Non-ergot DA agonists have also recently been used in the treatment of PD despite the lack of substantial evidence for any free radical scavenging activity or antioxidant activity. The present study was conducted to assess the in vitro free radical scavenging and antioxidant activities of ropinirole, a non-ergot DA agonist, as well as its glutathione (GSH), catalase and superoxide dismutase (SOD) activating effects and neuroprotective effect in vivo. Ropinirole scavenges free radicals and suppresses lipid peroxidation in vitro, but these activities are very weak, suggesting that the antioxidant effect of ropinirole observed in vitro may be a minor component of its neuroprotective effect in vivo. Administration of ropinirole for 7 days increased GSH, catalase and SOD activities in the striatum and protected striatal dopaminergic neurons against 6- hydroxydopamine (6-OHDA) in mice. Pre-treatment with sulpiride prevented ropinirole from enhancing striatal GSH, catalase and SOD activities and abolished the protection of dopaminergic neurons against 6-OHDA. Our findings indicate that activation of GSH, catalase and SOD mediated via DA D2 receptors may be the principal mechanism of neuroprotection by ropinirole.

DOI： 10.1016/S0006-8993(99)01688-1

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DOI： 10.1023/a:1020915727119

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We examined the effects of oxidative stress on rat cultured mesencephalic neurons and glial cells. Glial cells were more resistant to 6- hydroxydopamine (6-OHDA) and H2O2 toxicity than neurons. In glial cells, incubation with 6-OHDA and H2O2 induced a significant increase in the expression of γ-glutamylcysteine synthetase (the rate-limiting enzyme in glutathione synthesis) mRNA, which correlated well with increased TPA- response element (TRE)-binding activity. Furthermore, a subsequent elevation in cellular total glutathione content was also observed. In neurons, both agents decreased TRE-binding activity, and these cells failed to up-regulate the glutathione synthesis. We also examined the mechanisms of the neuroprotective effects of glial cells using a gila conditioned medium. Neurons maintained in gila conditioned medium up-regulated the level of TRE- binding activity, γ-glutamylcysteine synthetase mRNA expression, and total glutathione content in response to 6-OHDA or H2O2, and became more resistant to both agents than cells maintained in a normal medium. Neurons maintained in normal medium failed to up-regulate the glutathione synthesis. Our results suggest that transcriptional up-regulation of glutathione synthesis in glial cell appears to mediate brain glial cell resistance against oxidative stress, and that glial cells protect neurons via transcriptional up-regulation of the antioxidant system.

DOI： 10.1046/j.1471-4159.1999.0722334.x

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Language：Japanese   Publisher：日本神経化学会  

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DOI： 10.1016/s0304-3940(98)00489-3

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DOI： 10.1016/s0168-0102(97)00128-4

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Language：Japanese   Publisher：日本生物学的精神医学会・日本神経精神薬理学会  

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Language：Japanese   Publisher：日本生物学的精神医学会・日本神経精神薬理学会  

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Language：Japanese   Publishing type：Book review, literature introduction, etc.   Publisher：PHARMACEUTICAL SOC JAPAN  

We previously reported that adrenocorticotropic hormone (ACTH) -treated rats serve as a valuable animal model for tricyclic antidepressant-resistant depressive conditions. The present study was undertaken to investigate the changes in neurogenesis in the hippocampus of ACTH-treated rats. Chronic treatment of ACTH decreased the number of bromodeoxyuridine-labeled cells in the dentate gyrus, and the coadministration of imipramine and lithium, and electroconvulsive stimuli recovered these reductions. Furthermore, chronic ACTH treatment also decreased the expression of brain-derived neurotrophic factor, and the coadministration of imipramine and lithium, and electroconvulsive stimuli recovered these reductions. These results suggest that antidepressant-resistant depression is caused by the suppression of neurogenesis, and the coadministration of imipramine and lithium, and electroconvulsive stimuli exert an antidepressant-like effect by recovering proliferative signals and neurogenesis.

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：ELSEVIER IRELAND LTD  

DOI： 10.1016/j.neures.2011.07.820

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DOI： 10.1016/j.neures.2011.07.372

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DOI： 10.1016/j.neures.2011.07.821

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：JAPANESE PHARMACOLOGICAL SOC  

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DOI： 10.1016/j.neures.2010.07.138

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DOI： 10.1016/j.neures.2010.07.1537

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：WILEY-BLACKWELL PUBLISHING, INC  

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DOI： 10.1016/j.neures.2009.09.1458

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DOI： 10.1016/j.neures.2009.09.577

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Nonsteroidal anti-inflammatory drugs (NSAIDs) exert anti -inflammatory, analgesic and antipyretic activities and are involved in the suppression of prostaglandin synthesis by inhibiting cyclooxygenase (COX), a prostaglandin synthesizing enzyme. It has been recently revealed that NSAIDs also possess inhibitory effects on the generating system of nitric oxide radicals and modulating effects on transcription factors and nuclear receptors which are related to inflammatory reactions. Since it has been reported that inflammatory processes are associated with the pathophysiology of several neurodegenerative diseases and that NSAIDs inhibit amyloid β-protein-induced neurotoxicity to reduce the risk for Alzheimer's disease, a number of studies have been conducted focusing on the neuroprotective effects of NSAIDs. It has been clarified that the drugs exert neuroprotective effects, which are not related to their COX-inhibiting property, on pathophysiology of various neurological disorders. In this article, new aspects of neuroprotective effects of NSAIDs have been reviewed, especially, in Alzheimer's disease and Parkinson's disease, discussing various pharmacological effects of NSAIDs other than their inhibitory action on COX.

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Event date： 2019.7.9 - 2019.7.13

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