Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Parkinson's disease (PD) is one of the most important neurodegenerative worldwide disorders. It is characterized by a selective and progressive degeneration of dopaminergic neurons, causing a series of symptoms which might ultimately induce programmed cell death. The potential cytoprotective effects of one of the commercial extracts of Anemopaegma mirandum (Catuaba), a Brazilian tree, on Rotenone-induced apoptosis in human neuroblastomas SH-SY5Y cells was demonstrated. The cell viability, analysis of cellular morphology, nuclei morphology and ultra structural research were done by MTT-tetrazole (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, phase contrast microscopy, stained with Hoechst 33258 and electron microscopy transmission, respectively. Three different concentrations of Catuaba extract were used (0.312, 0.625 and 1.250 mg/mL). These extracts promoted an increase of 22.3+/-3.6%, 22.0+/-2.1% and 15.8+/-0.7% on the cell viability. Notable changes in the cellular morphology, condensation of the cell body, nuclear fragmentation and condensation into discrete dense chromatin clumps were observed when the cells were treated with 300 nM Rotenone for 48 h. These effects were partially altered when the extract of A. mirandum was added to the Rotenone treatment. Ultra structural analysis by electron microscopy demonstrated that citoplasmatic membranes and mitochondria membrane were also clearly preserved in the group treated with the extract. Therefore, in this study, our findings indicated that extracts of A. mirandum have cytoprotective effects on Rotenone-induced apoptosis in human neuroblastomas SH-SY5Y cells.
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PMID:Effects of the extract of Anemopaegma mirandum (Catuaba) on Rotenone-induced apoptosis in human neuroblastomas SH-SY5Y cells. 1824 47

Disrupted iron metabolism and excess iron accumulation has been reported in the brains of Parkinson's disease (PD) patients. Because excessive iron can induce oxidative stress subsequently causing degradation of nigral dopaminergic neurons in PD, we determined the protective effect of a naturally occurring iron chelator, phytic acid (IP6), on 1-methyl-4-phenylpyridinium (MPP(+))-induced cell death in immortalized rat mesencephalic/dopaminergic cells. Cell death was induced with MPP(+) in normal and iron-excess conditions and cytotoxicity was measured by thiazolyl blue tetrazolium bromide (MTT assay) and trypan blue staining. Apoptotic cell death was also measured with caspase-3 activity, DNA fragmentation, and Hoechst nuclear staining. Compared to MPP(+) treatment, IP6 (30 micromol/L) increased cell viability by 19% (P<0.05) and decreased cell death by 22% (P<0.05). A threefold increase in caspase-3 activity (P<0.001) and a twofold increase in DNA fragmentation (P<0.05) with MPP(+) treatment was decreased by 55% (P<0.01) and 52% (P<0.05), respectively with IP6. Cell survival was increased by 18% (P<0.05) and 42% (P<0.001) with 30 and 100 micromol/L of IP6, respectively in iron-excess conditions. A 40% and 52% (P<0.001) protection was observed in caspase-3 activity with 30 and 100 micromol/L IP6, respectively in iron-excess condition. Similarly, a 45% reduction (P<0.001) in DNA fragmentation was found with 100 micromol/L IP6. In addition, Hoechst nuclear staining results confirmed the protective effect of IP6 against apoptosis. Similar protection was also observed with the differentiated cells. Collectively, our results demonstrate a significant neuroprotective effect of phytate in a cell culture model of PD.
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PMID:Neuroprotective effect of the natural iron chelator, phytic acid in a cell culture model of Parkinson's disease. 1825 13

Olfactory ensheathing cells (OECs) express a high level of growth factors which play a very important role as neuronal support. Recent evidence in literatures showed that transplantation of OECs may improve functional restoration in 6-OHDA-induced rat model of Parkinson's disease (PD). However, the biological function of various factors released from OECs in Parkinson' disease is still unclear. In this study, we examined the effects of newborn rat OECs conditioned medium (CM) on PC12 cells. Cells treated with 6-OHDA underwent cytotoxicity and apoptotic death determined by MTT assay and Hoechst 33342/PI staining. OECs CM was able to reduce the cellular damage in PC12 cells. Further investigation results showed that CM inhibited the disruption of mitochondrial transmembrane potential, up-regulation of Bcl-2 and down-regulation of Bax. Taken together, this study indicates that CM has a neuroprotective effect on 6-OHDA induced apoptosis of PC12 cells, which is through up-regulation of the Bcl-2/Bax ratio and protection for mitochondrion.
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PMID:Olfactory ensheathing cells conditioned medium prevented apoptosis induced by 6-OHDA in PC12 cells through modulation of intrinsic apoptotic pathways. 1829 31

The neurotoxicity of l-3,4-dihydroxyphenylalanine (L-DOPA), used for the treatment of Parkinson's disease, remains controversial. Although there are many reports suggesting that long-term treatment of L-DOPA causes neuronal death, an increasing body of recent evidence has proposed that L-DOPA might be neuroprotective rather than neurotoxic. We investigated the effect of L-DOPA on neuronally differentiated PC12 (nPC12) cells by treating cells with various concentrations of L-DOPA for 24h. We also studied whether glycogen synthase kinase (GSK)-3 activation is related to L-DOPA-induced neurotoxicity by simultaneously treating cells with several concentrations of L-DOPA and a GSK-3 inhibitor for 24h. MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay, trypan blue staining, cell counting kit-8, and DAPI staining all showed that L-DOPA decreased nPC12 cell viability at high concentrations. In addition, 100 microM L-DOPA treatment significantly increased the activity of GSK-3 and death signals including cytochrome c, activated caspase-3 and cleaved PARP, and decreased survival signals including heat shock transcription factor-1 in a concentration-dependent manner. Treatment with GSK-3 inhibitor VIII or lithium chloride prevented L-DOPA-induced cell death. Together, these results suggest that L-DOPA induces neuronal cell death at high concentrations and that the neurotoxic effect of L-DOPA might be mediated in part by GSK-3 activation.
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PMID:Inhibition of glycogen synthase kinase-3 reduces L-DOPA-induced neurotoxicity. 1838 27

Parkinson's disease (PD) is one of the most important neurodegenerative worldwide disorders. The potential cytoprotective effects of aqueous extract of Valeriana officinalis on rotenone-induced apoptosis in human neuroblastoma SH-SY5Y cells were demonstrated. The cytotoxicity, cell viability and analysis of cellular morphology were performed by MTT-tetrazole (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and phase contrast microscopy, respectively. Significant changes in the cellular morphology, and condensation of the cell body could be observed when cells were treated with 300 nM rotenone for 48 h. Three different concentrations of Valeriana officinalis extract were used (0.049, 0.098 and 0.195 mg/mL). These extracts brought about an increase of 7.0 +/- 1.3%, 14.5 +/- 1.3% and 14.5 +/- 3.2% in cell viability. Our results indicated that neuroprotector action of the Valeriana officinalis extract provides support for later studies as they help understanding this drug for the development of cytoprotective various therapies in PD.
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PMID:Cytoprotective effect of Valeriana officinalis extract on an in vitro experimental model of Parkinson disease. 1851 51

Numerous reports have described the effects of quercetin in models of neurodegenerative diseases, or cancer, resulting in a very complex and sometimes paradoxical picture. Understanding how quercetin causes either protection or cell death in the same model is both tempting and essential. We used the 6-OHDA-induced toxicity model in SH-SY5Y cells, applying graded concentrations of quercetin for a variable time period and following cell viability with MTT-assay and LDH-release as well as caspase-3-like activity. We detected a time-dependent action of quercetin and distinguished an early protective effect from a late toxic one. In addition, we revealed a narrower therapeutic dose-range of quercetin than previously reported in the literature, demonstrating that the toxic effects of quercetin occurred at a concentration only 2-fold higher than the one that produced the greatest protection. We also demonstrated, to our knowledge for the first time, that quercetin itself directly inhibits caspase-3-like activity in a dose-dependent manner. Finally, single doses of quercetin failed to protect against 6-OHDA toxicity in a unilateral rat model of Parkinson's disease. In conclusion, our data may offer an explanation for the dualistic effect of quercetin reported in the literature. In fact, in most studies suggesting quercetin protection against oxidative stressors, the experimental setting failed to include prolonged exposure, and therefore the toxic effects may have been missed. This study supports previous in vivo studies that cast doubt on the efficacy of quercetin against neurodegenerative diseases due to its delayed toxicity.
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PMID:Time-dependent protective and harmful effects of quercetin on 6-OHDA-induced toxicity in neuronal SH-SY5Y cells. 1875 31

Aim of the present study was to investigate the neuroprotective effect of dental pulp cells (DPCs) in in vitro models of Alzheimer and Parkinson disease. Primary cultures of hippocampal and ventral mesencephalic neurons were treated for 24 h with amyloid beta (Abeta(1-42)) peptide 1-42 and 6-OHDA, respectively. DPCs isolated from adult rat incisors were previously cultured in tissue culture inserts and added to the neuron cultures 2 days prior to neurotoxin treatment. Cell viability was assessed by the MTT assay. The co-culture with DPCs significantly attenuated 6-OHDA and Abeta(1-42)-induced toxicity in primary cultures of mesencephalic and hippocampal neurons, and lead to an increase in neuronal viability in untreated cultures, suggesting a neurotrophic effect in both models. Furthermore, human dental pulp cells expressed a neuronal phenotype and produced the neurotrophic factors NGF, GDNF, BDNF, and BMP2 shown by microarray screening and antibody staining for the representative proteins. DPCs protected primary neurons in in vitro models of Alzheimer's and Parkinson's disease and can be viewed as possible candidates for studies on cell-based therapy.
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PMID:The neuroprotective effect of dental pulp cells in models of Alzheimer's and Parkinson's disease. 1897 63

In the present work, we showed that a chalcone-enriched fraction (CEF) isolated from the stem bark of a Brazilian medicinal plant, Myracrodruon urundeuva, presents neuroprotective actions on 6-hydroxydopamine (6-OHDA)-induced neuronal cell death, in rat mesencephalic cells. In the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium] assay, which is an index of cell viability, CEF (1-100 microg/ml) reversed in a concentration-dependent manner the 6-OHDA-induced cell death. While cells exposed to 6-OHDA (40 microM) showed an increased concentration of thiobarbituric acid reactive substances (TBARS), the pretreatment with CEF (10-100 microg/ml) significantly decreased the 6-OHDA-induced TBARS formation, indicative of a neuroprotection against lipoperoxidation. Furthermore, the drastic increase of nitrite levels induced by 6-OHDA, indicative of nitric oxide formation and free radicals production, was prevented by CEF. Double staining with acridine orange/ethidium bromide showed that cultures exposed to 6-OHDA (40 and 200 microM) presented an increase of apoptotic and necrotic cell numbers in a concentration-dependent manner. CEF (100 microg/ml) protected cells from apoptosis and necrosis and increased number of cells presenting a normal morphology. The immunohistochemical analysis for tyrosine hydroxylase (TH) positive neurons indicated that 6-OHDA (40 and 200 microM) caused a concentration-dependent loss of TH+ and TH- neurons. CEF protected both cells types from 6-OHDA-induced cell death. All together, our results demonstrated neuroprotective effects of chalcones, which are able to reduce oxidative stress and apoptotic injury caused by 6-OHDA. Our findings suggest that chalcones could provide benefits, along with other therapies, in neurodegenerative injuries, such as Parkinson's disease.
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PMID:Neuroprotective effects of chalcones from Myracrodruon urundeuva on 6-hydroxydopamine-induced cytotoxicity in rat mesencephalic cells. 1900 54

Acrolein, an unsaturated aldehydic product of lipid peroxidation, has been implicated in the pathogenesis of various neurodegenerative disorders including Parkinson's disease. However, protection against acrolein toxicity in neuronal cells via chemical upregulation of cellular aldehyde-detoxification factors has not been investigated. In this study, we have investigated the induction of glutathione (GSH), GSH S-transferase (GST), and aldose reductase (AR) by the unique nutraceutical compound 3H-1,2-dithiole-3-thione (D3T); and the protective effects of the D3T-mediated cellular defenses on acrolein-mediated toxicity in human neuroblastoma SH-SY5Y cells. Incubation of SH-SY5Y cells with D3T (10-100 microM) resulted in a marked concentration- and time-dependent induction of GSH, but not GST or AR. D3T treatment also led to increased mRNA expression of gamma-glutamylcysteine ligase (GCL), the key enzyme in GSH biosynthesis. Incubation of SH-SY5Y cells with 40 microM acrolein for 0.5 or 1 h resulted in a significant depletion of cellular GSH, which preceded the decrease of cell viability, suggesting critical involvement of GSH in acrolein-induced cytotoxicity. Pretreatment of SH-SY5Y cells with 100 microM D3T afforded a dramatic protection against acrolein-induced cytotoxicity, as assessed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium (MTT) reduction, lactate dehydrogenase release, as well as morphological changes. To further demonstrate the involvement of GSH in protection against acrolein-induced cytotoxicity, buthionine sulfoximine (BSO) was used to inhibit cellular GSH biosynthesis. Depletion of cellular GSH by 25 microM BSO dramatically potentiated acrolein-induced cytotoxicity. Cotreatment of SH-SY5Y cells with BSO and D3T was found to prevent the D3T-mediated GSH induction and completely reverse the cytoprotective effects of D3T on acrolein-induced toxicity. Taken together, this study demonstrates that upregulation of GSH is a predominant mechanism underlying D3T-mediated protection against acrolein-induced neurocytotoxicity.
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PMID:Upregulation of cellular glutathione by 3H-1,2-dithiole-3-thione as a possible treatment strategy for protecting against acrolein-induced neurocytotoxicity. 1907 13

Dopamine (DA) has been implicated as an endogenous neurotoxin to explain the selective neurodegeneration as observed for Parkinson's disease (PD). In addition, oxidative stress and lipid peroxidation are hypothesized culprits in PD pathogenesis. DA undergoes catabolism by monoamine oxidase (MAO) to 3,4-dihydroxyphenylacetaldehyde (DOPAL), which is further oxidized to 3,4-dihydroxyphenylacetic acid (DOPAC) via aldehyde dehydrogenase (ALDH). As a minor and compensatory metabolic pathway, DOPAL can be reduced to 3,4-dihydroxyphenylethanol (DOPET) via cytosolic aldehyde or aldose reductase (AR). Previous studies have found DOPAL to be significantly more toxic to DA cells than DA and that the major lipid peroxidation products, that is, 4-hydroxynonenal (4HNE) and malondialdehyde (MDA), potently inhibit DOPAL oxidation via ALDH. The hypothesis of this work is that lipid peroxidation products inhibit DOPAL oxidation, yielding aberrant levels of the toxic aldehyde intermediate. To test this hypothesis, nerve growth factor-differentiated PC6-3 cells were used as a model for DA neurons. Cell viability in the presence of 4HNE and MDA (2-100 microM) was measured by MTT assay, and it was found that only 100 microM 4HNE exhibited significant cytotoxicity. Treatment of cells with varying concentrations of 4HNE and MDA resulted in reduced DOPAC production and significant elevation of DOPAL levels, suggesting inhibition of ALDH. In cells treated with 4HNE that exhibited elevated DOPAL, there was a significant increase in DOPET. However, elevated DOPET was not observed for the cells treated with MDA, suggesting MDA to be an inhibitor of AR. Using isolated cytosolic AR, it was found that MDA but not 4HNE inhibited reductase activity toward DOPAL, surprisingly. These data demonstrate that the oxidative stress products 4HNE and MDA inhibit the aldehyde biotransformation step of DA catabolism yielding elevated levels of the endogenous neurotoxin DOPAL, which may link oxidative stress to selective neurodegeneration as seen in PD.
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PMID:Products of oxidative stress inhibit aldehyde oxidation and reduction pathways in dopamine catabolism yielding elevated levels of a reactive intermediate. 1938 87


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