Protective Effects of Curcumin Against Rotenone and Salsolinol-Induced Toxicity: Implications for Parkinson’s Disease

Abstract

Parkinson’s disease (PD) is a debilitating neurodegenerative disorder that results from the loss of or damage to dopaminergic cells in the substantia nigra. Exposure to either the pesticide rotenone or the endogenous neurotoxin salsolinol has been shown to mimic this dopaminergic cell loss. In this study we first sought to determine whether combination of rotenone and salsolinol would result in an additive or synergistic toxicity. For this purpose we utilized SH-SY5Y cells, a human neuroblastoma cell line that is commonly used to model dopaminergic neurodegeneration. We then tested whether curcumin, a natural plant compound with known health benefits including potential neuroprotective properties, could also protect against rotenone and/or salsolinol induced toxicity. Moreover, since apoptotic mechanism has been implicated in toxicity of these compounds the anti-apoptotic effect of curcumin was also evaluated. Our results indicate a synergistic toxicity of low concentrations of rotenone (1 and 5 uM) and salsolinol (25 and 50 mM) that was associated with apoptosis as determined by cell flow cytometry. There was also an increase in caspase-3 levels. Pretreatment with curcumin (1-10 uM) dose-dependently attenuated rotenone and/or salsolinol induced toxicity and the associated apoptosis. These results suggest that exposure to a combination of rotenone and salsolinol may contribute to the pathology of PD, and that curcumin has a therapeutic potential in this disease.

Neuroprotective efficacy of naringin on 3-nitropropionic acid-induced mitochondrial dysfunction through the modulation of Nrf2 signaling pathway in PC12 cells

“…Recent studies have suggested that the flavonoids exhibit protection against neurodegeneration [19,20]. Naringin, a well-known flavanone glycoside of grape fruits, e.g., Citrus paradise, Citrus unshiu, and Citrus sinensis, has been reported to attenuate the oxidative stress, apoptosis, and inflammation, demonstrated to possess neuroprotective effect [21,22].…”

Curcumin-Protected PC12 Cells Against Glutamate-Induced Oxidative Toxicity

“…Curcumin rescued α-synuclein-induced cell death (15). By targeting histone deacetylase (HDAC), curcumin promisingly prevented apoptosis and improved motor defi cits in Parkinson's disease (PD) in rat model (16,17).…”

Catechol Tetrahydroisoquinolines Enhance a-Synuclein Aggregation and Specify the Neurotoxicity to Dopaminergic Neurons

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