Evaluation of the Fas/FasL signaling pathway in diabetic rat testis

We investigated the role of the Fas/Fas ligand (FasL) signaling pathway in diabetic male infertility. Male rats were divided into two groups: a control group and a streptozotocin induced diabetic group. Thirty days after induction of diabetes, samples of testes were harvested and fixed in 10% formalin for light microscopy. Germ cell apoptosis was determined using the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate in situ nick end-labeling (TUNEL) and immunostaining of caspase 8 and active caspase 3. We also investigated the expressions of Fas and FasL using immunohistochemistry. Streptozotocin-induced diabetes caused severe histopathological damage and increased apoptotic tubule and apoptotic cell indices, caspase 8 and caspase 3 expressions, and Fas and FasL-immunopositive cells in the rat testes. We suggest that the Fas/FasL signaling pathway may play a role in male infertility caused by diabetes.