Glucagon-like peptide-1 (GLP-1) has been demonstrated to affect the oxidative stress status in several in vitro, in vivo and clinical studies. The aim of the present study was to evaluate the effect of a GLP-1 analogue, exenatide, on oxidative stress parameters and apoptotic markers in testicular cells in an iron overload rat model. To obtain this model, the animals were randomly divided into three groups (n=6/group). Rats in the control group received intraperitoneal injections of saline. Intraperitoneal iron dextran (60 mg/kg/day) was given to Group FE for 5 days a week for 4 weeks. The third group (Group Fe +E) was given subcutaneous injections of 10 µg/kg exenatide in two divided doses for 4 weeks in addition to iron dextran. Testes of all rats were immediately removed for immunohistochemical staining and to measure the malondialdehyde level and superoxide dismutase enzyme activity. A significant reduction was observed in caspase-8 and -3 enzyme staining in testicular stromal and endothelial cells in exenatide injected iron overloaded rats when compared with controls. Oxidative stress markers malondialdehyde levels and superoxide dismutase enzyme activities were also significantly lower in exenatide-injected rats when compared with controls. These findings indicate that exenatide may be protective against the harmful effects of iron accumulation in testis. Further studies are required to evaluate how exenatide reduces oxidative stress and cell death in iron overloaded testis tissue.
Keywords: caspase-3; caspase-8; exenatide; iron; malondialdehyde; superoxide dismutase.