Resumo

Green tea consumption is known to have beneficial effects to human health. Methylmercury (MeHg) and Cadmium [Cd(II)] are strong neurotoxic compounds which lead to neurological and developmental deficits in animals and humans. However, little is known about the molecular mechanisms of those metals. This work evaluated the effect of the major green tea polyphenol, Epigallocatechin-gallate (EGCG) 100 μM on viability (MTT assay), lipid peroxidation (TBARS assay) and nonprotein thiols formation (NPSH assay) in mitochondrial-enriched fractions from rat brain exposed to metals [MeHg 300 μM and Cd(II) 200 μM]. Data were analyzed by one-way ANOVA, followed by a post hoc analysis (Tukey’s test), P< 0.05. Preliminary data showed that co-incubation with EGCG and metals triggered an increase of 35% and 24% in mitochondrial viability when compared with MeHg and Cd(II), respectively, which in the latter case completely inhibited the reduction in mitochondrial viability. Moreover, EGCG completely prevented the lipid peroxidation induced by Cd(II) but not by MeHg and did not alter nonprotein thiols formation. This study demonstrates that EGCG can exert protective effects on mitochondrial viability and lipid peroxidation probably due to its antioxidant or chelating effects suggesting that small doses of this polyphenols could have beneficial effects on neural cells.