Hara P. Misra

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The effect of the neurotoxicant, 1-methyl-4-phenylpyridinium ion (MPP+) on acetylcholinesterase (AchE) activity was investigated. The MPP+ was found to inactivate the enzyme in a dose dependent manner. The kinetic parameter, Km for the substrate (acetylthiocholine), was found to be 0.216 mM and Ki for MPP+ for the inactivation of AChE was found to be 0.197(More)
Alpha-lipoic acid (LA) has recently been reported to afford protective effects in neurodegenerative disorders. However, the mechanisms underlying LA-mediated neuroprotection remain to be investigated. This study was undertaken to determine whether LA treatment could increase endogenous antioxidants and phase 2 enzymes in cultured human neuroblastoma SH-SY5Y(More)
Evidence suggests oxidative and electrophilic stress as a major factor contributing to the neuronal cell death in neurodegenerative disorders, especially Parkinson's disease. Consistent with this concept, administration of exogenous antioxidants has been shown to be protective against oxidative/electrophilic neurodegeneration. However, whether induction of(More)
Ethyl pyruvate (EP) has recently been reported to afford protection against neurodegenerative disorders. However, the mechanism underlying EP-mediated neuroprotection remains to be elucidated. Because peroxynitrite has been extensively implicated in the pathogenesis of various forms of neurodegenerative disorders via its cytotoxic effects, this study was(More)
Hypoxia may result from hypoperfusion, as seen in the cardio-respiratory arrest. Subsequent to the acute neuronal damage, the delayed neuronal death ensues, and further neurons die within hours or days thereafter. An effective neuroprotective therapeutic agent should counteract one or, ideally, all well-established neuronal death pathways, i.e.,(More)
Several epidemiological studies have suggested a role for environmental pesticide exposures in idiopathic Parkinson's disease. The purpose of this study was to test the hypothesis that exposure to pesticides such as endosulfan and/or zineb during critical periods of postnatal development could result in neuronal dysfunction and enhance the impact of these(More)
Mesalamine (5-aminosalicylic acid, 5-ASA) is known to be the first-line medication for treatment of patients with ulcerative colitis. Studies have demonstrated that ulcerative colitis patients treated with 5-ASA have an overall decrease in the risk of developing colorectal carcinoma. However, the mechanisms underlying 5-ASA-mediated anti-inflammatory and(More)
Dopamine auto-oxidation and the consequent formation of reactive oxygen species and electrophilic quinone molecules have been implicated in dopaminergic neuronal cell death in Parkinson's disease. We reported here that in PC12 dopaminergic neuronal cells dopamine at noncytotoxic concentrations (50-150 muM) potently induced cellular glutathione (GSH) and the(More)
The neurotoxicant 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) has been shown to reversibly inhibit the activity of acetylcholinesterase. The inactivation of the enzyme was detected by monitoring the accumulation of yellow color produced from the reaction between thiocholine and dithiobisnitrobenzoate ion. The kinetic parameter, Km for the substrate(More)
The effect of the neurotoxicant 1-methyl-4-phenyl-2,3-dihydropyridinium ion (MPDP+) on acetylcholinesterase (AchE) activity was investigated. The MPDP+ was found to inhibit the enzyme in a dose-dependent manner. The kinetic parameter, Km, for the substrate acetylthiocholine was found to be 0.22 mM, and the Kis and Kii for MPDP+ inhibition of AChE were found(More)