Treadmill exercise prevents leptin-induced decline in testicular and sperm parameters in male sprague-dawley rats

Elevated leptin levels have detrimental effects on sperm parameters and testicular tissue in Sprague-Dawley rats. Although some forms of low-to-moderate physical activity has been shown to improve health, whether regular physical exercise could prevent the adverse effects of exogenous leptin administration on sperm and testicular parameters, remains unknown. This study, therefore, examined the effects of treadmill running on leptin-induced adverse effects on sperm and testicular parameters in male rats. A total of 32 male Sprague-Dawley rats, aged 12 weeks, were divided into 4 equal groups. The rats received intraperitoneal injections as follows: Group 1 (Control) received 0.1 ml of normal saline; Group 2 (Leptin) received 60 μg/kg of leptin; Group 3 (Leptin+Exercise) received 60 μg/kg of leptin combined with exercise; and Group 4 (Exercise) received exercise alone. The exercise regimen consisted of treadmill running 4 times per week for 42 days (6 weeks). Each exercise session consisted of running at a speed of 0.5 m/s at 5° inclination on the treadmill for 30 minutes. Food and water intake, and body weight were measured weekly. Following the completion of treatment on day 43, the rats were euthanised and reproductive organs were collected. The weight of the organs (testes and epididymis) was determined. Total sperm count and fraction of sperm with abnormal morphology, seminiferous tubular height and diameter, concentration of 8-OHdG, sperm DNA damage, catalase and glutathione peroxidase activities, and expression of connexin-43 and occludin were determined. Data were analysed using ANOVA and Repeated Measures (RM) ANOVA followed by post-hoc analysis, and are expressed as mean ± SEM.