Investigation of the protective effect of pregabalin on diabetic rats sciatic nerve and brain tissue

Diabetes mellitus is a metabolic disorder based on uncontrolled blood glucose concentration that affects majority of human population. Pregabalin (PGB) has demonstrated efficacy for epilepsy, generalized anxiety disorder and in several neuropathic pain. In this study, the protective effects of PGB are investigated in rat brain and sciatic tissue with streptozotocin (STZ) - induced experimental diabetes. Twenty eight Wistar Albino male rats (aged 8 week) were used in this study. Rats were randomly assigned to four groups each consisting of seven animals. Rats in group Diabetic (DM) and group diabetic+pregabalin (DM+PGB) were injected with 180 mg/kg STZ solved in 0,1 M phosphate-citrate buffer (pH:4,5) intraperitoneally. After confirmed of experimental diabetes mellitus, no application was performed to group DM for 8 weeks. Rats in Group pregabalin (PGB) and group DM+PGB were administered with 50 mg/day PGB intraperitoneally for 8 weeks. At the end of experimental study rats were decapitated, brain and sciatic tissues were taken. Parafin sections were stained by histological, immunohistochemically and TUNEL protocols. In group DM, Malonildialdehit (MDA) concentrations were significantly higher than control; however glutation peroxidase (GPx) and superoxide dismutase (SOD) activities were lower than control. MDA concentrations were significantly lower in group DM+PGB than group DM, whereas SOD activity was higher. There was no different significantly between group PGB and control in whole biochemical examinations. In immunohistochemical examinations (bax, caspase-3 and TUNEL) of brain tissue, apoptotosis rate in DM + PGB was lower than group DM. Histological examination of sciatic nerve, myelin damage in DM + PGB group was significantly more lower than group DM. This study suggests that; PGB may decrease brain damage that caused by DM. PGB may be effective to reduce the risk for brain damage associated with DM.