Investigation of the protective effects of the preconditioning and nicotinamide against brain damage in with rats cerebral ıschemia-reperfusion by bilateral carotid occlusion

INTRODUCTION AND AIM: The aim of this study was to investigate the protective effects of nicotinamide and ischemic preconditioning against cerebral ischemia and reperfusion brain damage. MATERIALS AND METHODS: Thirty-five rats were randomly divided into five groups (n=7) as control, preconditioning ischemia/reperfusion (IO+IR), ischemia/reperfusion (IR), preconditioning ischemia/reperfusion+nicotinamide (IO+IR+N) and ischemia/reperfusion+nicotinamide (IR+N). Cerebral ischemia/reperfusion (CIR) was achieved by bilateral common carotid artery (CCA) occlusion. CCA occlusion was applied to the IO+IR and IO+IR+N groups 30 minutes before ischemia in the period of 10 seconds of ischemia and 30 seconds of reperfusion for 3 cycles, 20 minutes after ischemic preconditioning. Ischemia was given to the IR group for 20 minutes, and the IO+IR+N and IR+N groups were given nicotinamide at a dose of 500 mg/kg intraperitoneally. After the 24-hour reperfusion period, the animals were subjected to neurological evaluation and vertical rod test. Malondialdehyde (MDA), glutathione (GSH) levels and catalase (CAT) activity were measured in blood and brain tissue samples. In histopathological evaluations, the rates of red neuron, sateliosis and spongiosis were determined in the prefrontal cortex areas. RESULTS: After CIR, MDA levels in both serum and brain tissue increased significantly in the IR group compared to the control group (p <0.05), while GSH and CAT activity in brain tissue decreased (p <0.05). MDA levels in the brain and serum were found to be significantly decreased in the IR+N group compared to the IR group (p <0.05). Nicotinamide administration together with IO significantly decreased MDA levels in brain tissue, while increasing GSH and CAT activity (p <0.05). Compared to the IR group, it was found that the morphological and neurological damage size of the prefrontal cortex areas decreased in the in the IO+IR, IO+IR+N, and IR+N groups (p <0.05). CONCLUSION: Study results show that nicotinamide administration with ischemic preconditioning attenuates cerebral ischemia / reperfusion injury. Keywords: Nicotinamide, Oxidative stress, Preconditioning, Cerebral ischemia / reperfusion