Prophylactic and Therapeutic Effects of Carnosine in Ischemia Reperfusion Injury of Liver

Objective: Ischemia followed by reperfusion (IR) results in hepatocyte injury and apoptosis. Current study aims to investigate the prophylactic and therapeutic effects of antioxidant carnosine in liver ischemia and reperfusion injury in rats. Material and Methods: Five groups were formed with Wistar Albino female rats: Control group, IR group, Prophylaxis group (Carnosine and IR), Therapeutic group (IR + Carnosine), Prophylaxis and therapeutic group (Carnosine + IR + Carnosine). Total hepatic ischemia for 30 minutes and reperfusion for one week were administrated. Carnosine was given with 100 mg/day for one week. Tissue samples were prepared for histopathological, immunohistochemical and ultrastructural assessment. In addition, serum ALT and AST levels were determined. Results: In IR group, neutrophilic infiltration, sinusoidal dilatation, congestion and necrotic hepatocytes in some areas were observed. Ultrastructural assessment showed mitochondrial swelling and dilatation in granular endoplasmic reticulum (GER) cisterns. In prophylaxis group, localized collagen fibrils were observed in some Disse spaces. GER cisterns were dilated in therapeutic group. All cellular structures of prophylaxis and therapeutic group were similar to control group. In IR group, TUNEL positive hepatocyte count was higher than control group. In IR group, there was strong Bax labeling in hepatocytes. However, apoptotic cell count was the smallest in prophylaxis and therapeutic group followed by therapy after prophylaxis group. In IR group, Bcl-2 immune reaction was not observed whereas there was strong expression in prophylaxis and therapeutic group. Conclusion: In IR injury of liver, administration of carnosine in both prophylaxis and therapy instead of solely therapeutic or prophylactic administration prevents the apoptosis and structural changes.