Effect of DL-alpha-lipoic acid on the status of lipid peroxidation and protein oxidation in various brain regions of aged rats.

Free radicals have been implicated in the development of many acute and chronic diseases and in conditions involving brain or neurological tissue. The primary genetic material is subjected to damage by endogenous and exogenous agents, which may lead to instability and transcriptional infidelity. In the present study, we evaluated the protective effect of DL-alpha-lipoic acid, a metabolic antioxidant on lipid peroxidation, protein carbonyl content in various brain regions of aged rats when compared to brain regions of young rats. DL-alpha-lipoic acid was administered intraperitoneally (100mg/kg body weight/day) to experimental rats. Nucleic acid and protein content were low whereas thiobarbituric acid reactive substances and protein carbonyl content (markers of free radical damage) were high in cortex, striatum, hippocampus and hypothalamus followed by cerebellum of aged rat brain. Lipoate administration for 14 days in aged rats increased the levels of nucleic acid and protein and reduced lipid peroxidation and protein oxidation. These results demonstrate that lipoic acid is a potent antioxidant for neuronal cells against age associated oxidative damage.