Naringenin attenuates testicular damage, germ cell death and oxidative stress in streptozotocin induced diabetic rats: naringenin prevents diabetic rat testicular damage

The aim of this study was to investigate the protective effect of naringenin on oxidative stress, on pro-inflammatory cytokines like TGF-beta 1, IL-1 beta and on programmed cell death in the testicular damage resulting from streptozotocin (STZ) induced diabetes in rats. Diabetes was induced by a single intraperitoneal injection of STZ (50 mg/kg), and the rats were treated with naringenin (5 mg/kg and 10 mg/ kg) administered once a day orally for 10 weeks, starting 3 days after the STZ injection. At the end of the study, all animals were sacrificed. Testis tissue and blood samples were collected for the assessment of sperm parameters, and for biochemical and histopathological analysis. Naringenin treatment significantly decreased the levels of elevated tissue TBARS (thio-barbituric acid) and increased the superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) enzyme activities in the testis tissues. The naringenin-treated rats in the diabetic group showed an improved histological appearance, sperm parameters, and serum testosterone levels, along with a decrement of terminal dUTP nick end-labeling (TUNEL) detected program cell death and a reduced over expression of TGF-beta 1, IL-1 beta in Sertoli cells and Leydig cells. These results suggest that naringenin is a food supplement potentially beneficial in reducing testicular damage in diabetic rats by decreasing the oxidative stress related to programmed cell death.