Investigation of effects of vitamin D on irisin and apoptosis in experimental diabetic rat's testicular tissue

Diabetes is an important disease in the world that has been increasing day by day and affecting all biological tissues including testes. The aim of this study was to investigate the effects of vitamin D on testicular tissue histologically and biochemically on irisin, apoptosis, total antioxidant status (TAS) and total oxidant status (TOS). 41 male rats were divided into 5 groups. 7 animals were not treated in the first group (Control group). A single dose of 0.1 Molar (M) sodium citrate buffer was administered intraperitoneally (i.p) to 7 animals in the second group (Citrate buffer group). In the third group (Vitamin D group) 7 animals were given vitamin D 50 IU/day. 10 animals in the fourth group (Diabetes group) were given a single dose of 50 mg/kg Streptozotocin (STZ) in 0.1 M sodium citrate buffer to give i.p. 10 animals in the fifth group (Diabetes+vitamin D group) were given 50 mg/kg STZ, 0.1 M sodium citrate buffer in a single dose and given i.p. Seventy two hours later blood was collected from the tail vein and the blood glucose levels above 250 mg/dl were considered diabetic. After eight weeks, the rats were sacrificed and the testicular tissues were removed after the blood is taken from the tail vein of all rats. Testis tissues were examined histopathologically, immunohistochemically and by TUNEL method. The level of irisin in blood serum and testis tissue supernatants was analyzed by Enzyme Linked Immunosorbent Assay (ELISA) method. TAS and TOS results were evaluated by using REL method. In histological examination, decrease in the number of spermatogenic cells in seminiferous tubules was the most important finding in the testes of rats in the diabetes group, whereas vitamin D significantly prevented this condition. In immunohistochemical examination, it was observed that the level of irisin in the diabetic group decreased compared to the control group and vitamin D application increased the level of irisin. When apoptotic cell numbers were compared, it was observed that apoptotic cells in the diabetes group increased compared to the control group, whereas vitamin D application decreased the number of apoptotic cells. In biochemical analyzes, the levels of tissue and serum irisin and levels of TAS were decreased and the level of TOS was increased in the diabetes group. Diabetes+vitamin D group compared with the diabetes group, tissue and serum irisin levels and TAS levels were increased, while TOS level was found to be decreased. Vitamin D group was similar to diabetes+vitamin D group. As a result, it is thought that the application of vitamin D significantly eliminates the negative effects of diabetes on the testis and may contribute to the treatment of diabetes. Key Words: Diabetes, Testis, Irisin, Vitamin D, Apoptosis.