Protective effect of an extract of the oyster mushroom, Pleurotus ostreatus, on antioxidants of major organs of aged rats.

This study was undertaken to investigate the putative antioxidant activity of the oyster mushroom, Pleurotus ostreatus, on lipid peroxidation and antioxidant status of major organs of aged (24 month old) rats when compared to young (4 month old) rats. Elevated levels of malondialdehyde (MDA) and significantly lowered levels of reduced glutathione (GSH) and of vitamins C and E were observed in the liver, kidneys, heart and brain of aged rats, when compared to values in young rats. Quantitative analysis of the activities of the antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (Gpx) revealed significantly lower values in the liver, kidneys, heart and brain of aged rats. An analysis of isozyme pattern of these enzymes in aged rats also revealed variations in relative concentration, presumably due to oxidative stress. Administration of the extract of P. ostreatus to aged rats resulted in elevated levels of reduced glutathione and vitamins C and E and in increased activities of CAT, SOD and Gpx so that the values in most of these parameters did not differ significantly from those in young rats. In addition, the level of MDA was lowered on administration of mushroom extract to aged rats. These results suggest that treatment with an extract of P. ostreatus can improve the antioxidant status during ageing, therein minimizing the occurrence of age-associated disorders associated with involvement of free radicals.