Protective effect of Acorus calamus LINN on free radical scavengers and lipid peroxidation in discrete regions of brain against noise stress exposed rat.

Exposure to continuous loud noise is a serious health problem due to excess production of oxygen free radicals. In medical research, more attention is paid to the antioxidant properties of medicinal plants to minimize the harmful effects of radicals. The aim of this study was to evaluate the protective effect of both ethyl acetate and methanolic extract of Acorus calamus LINN against noise stress (30 d, 100 dBA/4h/d) induced changes in the rat brain. We measured the activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and the levels of reduced glutathione (GSH), vitamin C, vitamin E, protein thiols and lipid peroxidation (LPO) for the evaluation of oxidative stress status in discrete regions of the rat brain like cerebral cortex, cerebellum, pons-medulla, midbrain, hippocampus and hypothalamus. The results indicated that during exposure of noisy environment ROS generation led to increase in corticosterone, LPO and SOD, but decrease in CAT, GPx, GSH, protein thiols, vitamins C and E levels. Both the ethyl acetate and methanolic extract of Acorus calamus protected most of the changes in the rat brain induced by noise-stress.