The investigation of effects of alpha lipoic acid in the sciatic nerve and brain tissue of rats were created in experimental diabetes

Diabetes mellitus (DM) is a metabolic disorder characterized by hyperglycemia induced impairment of insulin secretion or activity. Biochemical, morphological and functional changes occur in tissues and organs of patients with diabetes. Endogenously synthesized alpha lipoic acid (ALA) is a specific protein, which function as cofactor for several important mitochondrial enzyme complexes. The studies have shown antioxidant effects of ALA. In this study, the protective effects of ALA were investigated in rat brain and sciatic tissue with streptozotocin (STZ) induced experimental diabetes. Twenty-eight adult male Wistar albino rats were used. Rats were randomly divided into four groups with seven rats per group. The groups were named as control, DM, ALA and DM+ALA. Rats in DM and DM+ALA groups were injected intraperitoneal streptozotocin (180 mg/kg) to establish diabetes mellitus rat model. Rats in ALA and DM+ALA groups were received alpha lipoic acid (100mg/kg/day, per oral) for eight weeks. After treatment for eight weeks, all of rats weighed and then decapitated. The brain and sciatic nerve tissues were removed. In DM group; level of MDA was statistically more higher than control group. In DM+ALA group; level of MDA was statistically more lower than DM group, level of GPx was higher than control and DM groups. In ALA group; level of MDA was lower than DM and DM+ALA groups, level of catalase (CAT) was higher than DM group, level of GPx was higher than control and DM groups, level of SOD was higher than DM+ALA group. In immunohistochemical examinations of brain tissue; in DM+ALA group, apoptosis was lower than DM group. Histological examination of sciatic nevre, myelin damage in DM+ALA group was significantly more lower than DM group. In conclusion, it is observed that ALA has protective effects against DM induced oxidative damage and apoptotic changes in the central and peripheral nervous systems. To prevent DM induced central and peripheral nervous systems complications, was concluded that treatment with ALA may be useful to challenge approaches. Key Words: Diabetes mellitus, Alpha lipoic acid, brain, sciatic nerve, oxidative damage