[Effects of aerobic exercise and dietary intervention on testicular oxidative stress in obese mice]

Through aerobic exercise and diet intervention on obese mice, the effects of exercise and diet intervention on testicular oxidative stress and p38MAPK-NF-κB pathway were investigated in obese mice.

Seventeen C57BL/6J mice were randomly divided into a normal diet group (ND), and 37 mice were divided into a high-fat diet group (HFD), the high-fat diet accounted for 40% of fat. After 12 weeks of feeding, 3 obesity-resistant mice were excluded from the HFD group, and the remaining 34 were successfully modeled. The mice in ND group were then divided into normal diet control group (NC, n=8) and normal diet and exercise group (NE, n=9). The mice in HFD group were divided into obese high-fat diet control group (OC, n=8), obese high-fat diet and exercise group (OE, n=9), obese normal diet group (ONC, n=8), and obese normal diet and exercise group (ONE, n=9). Each group continued to feed for 8 weeks, and the NE, OE and ONE groups performed treadmill exercise for 8 weeks at a speed of 20 m/min, 60 min/d, 6 d/week. Blood and testicular tissue samples were collected 36～40 h after the last exercise. Serum testosterone and testicular oxidative stress (MDA, T-SOD, T-AOC) levels were detected by ELISA, and testicular p38MAPK-NF-κB levels were detected by RT-PCR and Western blot.

Compared with the NC group, the body fat parameters, testicular MDA and testicular p38MAPK-NF-κB mRNA and protein levels in the OC group were increased significantly (P＜0.01), while the levels of testicular SOD, testis coefficient and blood testosterone were decreased significantly (P＜0.01); the body fat parameters of the mice in the NE group were decreased significantly (P＜0.05), and the serum level of testosterone was increased significantly (P＜0.01). Compared with the OC group, the body fat parameters, testicular MDA and testicular p38MAPK-NF-κB mRNA and protein levels were decreased significantly in the OE group (P＜0.05 or 0.01), and the testicular SOD and blood testosterone levels were increased significantly (P＜0.01); Body fat parameters, testicular MDA and testicular p38MAPK-NF-κB mRNA and protein levels were decreased significantly in ONC group (P＜0.01), while testicular SOD level and testis coefficient were increased significantly (P＜0.05); Body fat parameters, testicular MDA and testicular p38MAPK-NF-κB mRNA and protein levels of mice in ONE group were decreased significantly (P＜0.01), while testicular SOD, testis coefficient and blood testosterone levels were increased significantly (P＜0.01).

Obesity induces oxidative stress in the testis of mice, up-regulates the level of p38MAPK-NF-κB, and reduces the level of blood testosterone; exercise, diet and exercise*diet interventions can reduce testicular oxidative stress and down-regulate testicular p38MAPK-NF-κB levels by reducing body fat.