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

Parkinson's disease (PD) is a movement disorder resulting from nigrostriatal dopaminergic neurodegeneration. The impairment of mitochondrial function and dopamine synaptic transmission are involved in the pathogenesis of PD. Two mitochondrial inhibitors, 1-methyl-4-phenylpyridine (MPP(+)) and rotenone, have been used to induce dopaminergic neuronal death both in in vitro and in vivo models of PD. Because the uptake of MPP(+) is mediated by the dopamine transporter (DAT), we used a cell-permeable rotenone-induced PD model to investigate the role of DAT and dopamine D2 receptor (D2R) on dopaminergic neuronal loss. Rotenone subcutaneously infused for 14 days induced PD symptoms in rats, as indicated by reduced spontaneous locomotor activity (hypokinesis), loss of tyrosine hydroxylase (TH, a marker enzyme for dopamine neurons) immunoreactivity in the substantia nigra and striatum, obvious alpha-synuclein accumulation, downregulated DAT protein expression, and upregulated D2R expression. Interestingly, rotenone also caused significant noradrenergic neuronal loss in the locus coeruleus. Melatonin, an antioxidant, prevented nigrostriatal neurodegeneration and alpha-synuclein aggregation without affecting the rotenone-induced weight loss and hypokinesis. However, rotenone-induced hypokinesis was markedly reversed by the DAT antagonist nomifensine and body weight loss was attenuated by the D2R antagonist sulpiride. In addition, both antagonists significantly prevented the reduction of striatal TH or DAT immunoreactivity but not the loss of nigral TH- and DAT-immunopositive neurons. These results suggested that oxidative stress and DAT downregulation are involved in the rotenone-induced pathogenesis of nigrostriatal dopaminergic neurodegeneration, whereas D2R upregulation may simply represent a compensatory response.
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PMID:Melatonin reduces the neuronal loss, downregulation of dopamine transporter, and upregulation of D2 receptor in rotenone-induced parkinsonian rats. 1828 73

Rotenone, a potent specific inhibitor of mitochondrial complex-1, appears to reproduce the behavioral features of Parkinson's disease in rats. It destroys dopaminergic neurons selectively, causing deficiency of dopamine in striatum which leads to impaired motor functions. Oxidative stress generated as a result of mitochondrial dysfunction and metabolism of dopamine has been implicated as an important factor in the etiology of Parkinson's disease. Present study explores the potential of centrophenoxine (a well known anti-aging and antioxidant drug) against rotenone induced motor dysfunction. Sprague Dawley male rats were administered with rotenone on a daily basis by subcutaneous injection of dose: 2 mg/kg body weight over a period of 35 days. Data showed impaired motor function, significant increase in catalepsy, decrease in locomotor activity and decrease in muscle activity. Dopamine content of rotenone treated animals was found to decrease significantly and lipid peroxidation was found to increase significantly in rotenone treated animals when compared with co-treated group. Co-treatment with centrophenoxine (100 mg/kg i.p. for 35 days) significantly attenuated the extent of motor dysfunction and changes in the level of dopamine and lipid peroxidation induced by rotenone toxicity. Thus, the present study provides evidence that centrophenoxine co-treatment attenuates rotenone induced motor dysfunction by virtue of its antioxidant action.
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PMID:Behavioral alterations in rotenone model of Parkinson's disease: attenuation by co-treatment of centrophenoxine. 1830 96

Axonal degeneration is a prominent feature of many neurological disorders that are associated with mitochondrial dysfunction, including Parkinson's disease, motor neuron disease, and inherited peripheral neuropathies. Studies of the Wld(s) mutant mouse, which undergoes delayed Wallerian degeneration in response to axonal injury, suggest that axonal degeneration is an active process. Wld(s) mice also have slower axonal degeneration and disease progression in numerous models of neurodegenerative disease. The Wld(s) mutation results in the production of a chimeric protein that contains the full-length coding sequence of nicotinamide mononucleotide adenylyltransferase 1 (Nmnat1), which alone is sufficient for axonal protection in vitro. To test the effects of increased Nmnat expression on axonal degeneration induced by mitochondrial dysfunction, we examined dorsal root ganglion (DRG) neurons treated with rotenone. Rotenone induced profound axonal degeneration in DRG neurons; however, this degeneration was delayed by expression of Nmnat. Nmnat-mediated protection resulted in decreased axonal accumulation and sensitivity to reactive oxygen species (ROS) but did not affect the change in the rate of rotenone-induced loss in neuronal ATP. Nmnat also prevented axonal degeneration caused by exposure to exogenous oxidants and reduced the level of axonal ROS after treatment with vincristine, further supporting the idea that Nmnat promotes axonal protection by mitigating the effects of ROS.
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PMID:Nmnat delays axonal degeneration caused by mitochondrial and oxidative stress. 1846 39

Rotenone is a widely used pesticide. Administration of rotenone can induce biochemical and histological alterations similar to those of Parkinson's disease in rats, leading to the selective loss of dopaminergic neurons in the substantia nigra pars compacta. However, it remains unclear why rotenone seems to affect preferentially dopaminergic cells. To address this question, we studied the effects of rotenone on dopamine distribution and metabolism to determine the role of endogenous dopamine in rotenone-induced PC12 cells toxicity. Results showed that cell viability was decreased and intracellular dopamine concentration was increased with rotenone administration in a dose-dependent manner. Rotenone exposure led to changes of proteins and enzymes associated with dopamine synthesis and transportation in PC12 cells. Tyrosine hydroxylase (TH) and vesicular monoamine transporter 2 (VMAT(2)) were markedly down-regulated, and dopamine transporter (DAT) was up-regulated in the cells. The activity of monoamine oxidase (MAO) was also increased. In addition, rotenone increased ROS formation, which was clearly inhibited by the pretreatment of GSH. Similar inhibitions of ROS formation were also observed in PC12 cells pretreated with the classical dopamine transporter inhibitor of GBR-12909 and the MAO inhibitor L-deprenyl. Moreover, opposite effects were observed in PC12 cells pretreated with the specific VMAT(2) inhibitor reserpine. These results suggest that rotenone administration may interfere with dopamine distribution and metabolism, leading to dopamine accumulated in the cytoplasm of PC12 cells, which may contribute to the ROS formation and cell death. Therefore, the endogenous dopamine resulted from the altered dopamine metabolism and redistribution may play an important role in rotenone toxicity in dopamine neurons.
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PMID:Rotenone-induced PC12 cell toxicity is caused by oxidative stress resulting from altered dopamine metabolism. 1857 41

Mutations in the gene encoding the E3 ubiquitin-protein ligase parkin have been shown to be a common genetic cause of familial early-onset Parkinson's disease (PD). In addition to its function in the ubiquitin-proteasome system (UPS), parkin has been ascribed general neuroprotective properties. Stress and mutation induced decreases in parkin solubility leading to compromised cytoprotection have recently been reported. We systematically investigated whether PD-related stresses including MG132 and epoxomicin (proteasomal impairment), tunicamycin (unfolded protein stress), and rotenone (mitochondrial dysfunction) resulted in expressional changes of parkin and other E3 ubiquitin ligases (dorfin, SIAH-1). Rotenone and tunicamycin did not change parkin mRNA levels, whereas proteasomal inhibition resulted in a reduction of parkin mRNA in PC12 cells as well as in SH-SY5Y cells. Therefore, surprisingly, cells did not react with a compensatory parkin upregulation under proteasomal inhibition, although, in parallel, parkin protein shifted to the insoluble fraction, reducing soluble parkin levels in the cytosol. Since the mRNA of the parkin-coregulated gene PACRG paralleled the parkin mRNA at least partly, we suspect a promoter-driven mechanism. Our study, therefore, shows a link between proteasomal impairment and parkin expression levels in cell culture, which is intriguing in the context of the described and debated proteasomal dysfunction in the substantia nigra of PD patients.
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PMID:Proteasomal inhibition reduces parkin mRNA in PC12 and SH-SY5Y cells. 1858 49

Parkinson's disease is a progressive neurodegenerative disorder characterized by selective degeneration of nigrostriatal dopaminergic neurons. Long-term systemic mitochondrial complex I inhibition by rotenone induces selective degeneration of dopaminergic neurons in rats. We have reported dopamine redistribution from vesicles to the cytosol to play a crucial role in selective dopaminergic cell apoptosis. In the present study, we investigated how rotenone causes dopamine redistribution to the cytosol using an in vitro model of human dopaminergic SH-SY5Y cells. Rotenone stimulated nitration of the tyrosine residues of intracellular proteins. The inhibition of nitric-oxide synthase or reactive oxygen species decreased the amount of nitrotyrosine and attenuated rotenone-induced apoptosis. When we examined the intracellular localization of dopamine immunocytochemically using anti-dopamine/vesicular monoamine transporter 2 (VMAT2) antibodies and quantitatively using high-performance liquid chromatography, inhibiting nitration was found to suppress rotenone-induced dopamine redistribution from vesicles to the cytosol. We demonstrated rotenone to nitrate tyrosine residues of VMAT2 using an immunocytochemical method with anti-nitrotyrosine antibodies and biochemically with immunoprecipitation experiments. Rotenone inhibited the VMAT2 activity responsible for the uptake of dopamine into vesicles, and this inhibition was reversed by inhibiting nitration. Moreover, rotenone induced the accumulation of aggregate-like formations in the stained image of VMAT2, which was reversed by inhibiting nitration. Our findings demonstrate that nitration of the tyrosine residues of VMAT2 by rotenone leads to both functional inhibition and accumulation of aggregate-like formations of VMAT2 and consequently to the redistribution of dopamine to the cytosol and apoptosis of dopaminergic SH-SY5Y cells.
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PMID:Mitochondrial complex I inhibitor rotenone inhibits and redistributes vesicular monoamine transporter 2 via nitration in human dopaminergic SH-SY5Y cells. 1859 2

Patients with Parkinson's disease (PD) often have attenuated baroreflex function, which may occur before the onset of PD-associated movement disorders. The aim of the present study was to test whether impaired arterial baroreflex (ABR) function could contribute to the pathogenesis of PD. 6-Hydroxydopamine (8 mug in 4 mul) was microinjected into the left substantia nigra of rats to establish unilateral PD models, and bilateral PD models were established in rats by administration of rotenone by osmotic minipump for four weeks, at a dose of 2.5 mg . kg(-1) . day(-1). An ABR dysfunction model was obtained by performing sinoaortic denervation (SAD). Hemodynamic variables were determined in conscious rats. PD-like symptoms and dopamine content in corpus striatum (CS) were also assessed. 6-Hydroxydopamine and rotenone treatment and SAD were associated with enhanced blood pressure variability (BPV) and blunted baroreflex sensitivity (BRS). Rotenone, but not SAD, significantly reduced dopamine content in the CS, induced catalepsy, and inhibited rearing and exploratory behavior. SAD before the administration of rotenone did not aggravate the rotenone-induced dopaminergic lesion. Our findings do not support the presumption that ABR dysfunction contributes to the pathogenesis of PD in rats.
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PMID:Arterial baroreflex dysfunction fails to mimic Parkinson's disease in rats. 1877 11

Ceruloplasmin (Cp) is the strongest ferroxidase in human plasma. Hereditary deficiency of this protein, named aceruloplasminemia, is an interesting model to elucidate the pathogenesis and pathophysiology of neurodegeneration induced by oxidative stress. Enhanced oxidative stress due to excessive iron accumulation is observed in the brains of aceruloplasminemia patients. Rotenone, a selective mitochondrial complex I inhibitor, induces neurodegeneration mimicking Parkinson's disease. We investigated the influence of Cp deficiency upon neurodegeneration using rotenone-treated, Cp-deficient mouse brains. Immunohistochemical examination showed that acrolein, one of the products of lipid peroxides, and ubiquitin were more markedly immunoreacted in the brains of rotenone-treated, Cp-deficient mice than in rotenone-untreated, Cp-deficient or rotenone-treated, wild-type mice. These molecules were localized in neuronal cells. These results suggested that rotenone-induced lipid peroxidation and accumulation of ubiquitin immunoreactivity were enhanced in the absence of Cp. Therefore, Cp may protect neuronal cells from oxidative stress-induced neurodegeneration.
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PMID:Increased vulnerability to rotenone-induced neurotoxicity in ceruloplasmin-deficient mice. 1880 45

Mitochondrial dysfunction is a common characteristic of all neurodegenerative diseases. However, the cause of this dysfunction remains a mystery. Here, we discuss the potential role of mitochondrial fission and fusion in the onset and progression of neurodegenerative diseases. Specifically, we propose that an imbalance in mitochondrial fission and fusion may underlie both familial and sporadic neurodegenerative disorders. There is substantial evidence that links disruption of the mitochondrial fission and fusion equilibrium, resulting in abnormally long or short mitochondria, to neurodegeneration. First, hereditary mutations in the mitochondrial fusion GTPases optic atrophy-1 and mitofusin-2 cause neuropathies in humans. In addition, recent findings report increased mitochondrial fission in Parkinson's disease (PD) models and induction of mitochondrial fission by two proteins, PTEN-induced kinase 1 and parkin, which are mutant in familial forms of PD. Furthermore, mutant huntingtin, the disease-causing protein in Huntington's disease, alters mitochondrial morphology and dynamics. Rotenone, a pesticide and inducer of PD symptoms, and amyloid-beta peptide, which is causally linked to Alzheimer's disease, initiate mitochondrial fission. Finally, mitochondrial fission is an early event in ischemic stroke and diabetic neuropathies. In sum, a growing body of research suggests that a better understanding of mitochondrial fission and fusion and the regulatory factors involved may lead to improved treatments and cures for neurodegenerative diseases.
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PMID:Impairing the mitochondrial fission and fusion balance: a new mechanism of neurodegeneration. 1907 50


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