Effect of Eight Weeks of Aerobic Exercise and Vitamin D Supplementation on 8-hydroxy-2'-deoxyguanosine and O6-methylguanine DNA methyltransferase in Lung of Rats Poisoned with Hydrogen Peroxide

Prolonged exercise can reduce physiological capacities and cause DNA damage by inducing oxidative stress and inflammatory responses. Aerobic exercise reduces the risk of cancer by activating DNA repair enzymes and reducing oxidative stress. The aim of the present study was to investigate effects of eight weeks of aerobic exercise with and without vitamin D supplementation on DNA damage.

Forty-eight adult male rats were randomly divided into six groups: control (C), H2O2 (H), H2O2 and vitamin D (HD), H2O2 and exercise (HE), H2O2,, vitamin D and exercise (HDE), and dimethyl sulfoxide. Cancer was stimulated through intraperitoneal injection of H2O2 (2 mmol/kg). Animals in groups HE and HDE ran on treadmill for eight weeks. Concentration of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and O6-methylguanine DNA methyltransferase (MGMT) was measured by enzyme-linked immunosorbent assay. Statistical analysis of data was carried out using SPSS 22 at significance level of 0.05.

Vitamin D supplementation significantly lowered the level of 8-OHdG expression compared to the control group (P=0.0001). The 8-OHdG expression in the exercise group was slightly lower than control group (P=0.063). Combination of exercise and vitamin D supplementation had no significant effect on expression of 8-OHdG (P=0.281). Both exercise and vitamin D supplementation significantly increased MGMT expression compared to the control group (P=0.0001 and P=0.040). However, combination of exercise and vitamin D supplementation had no significant effect on MGMT expression (P=0.326).

The results showed that aerobic exercise and vitamin D supplementation can have protective effects against DNA damage, possibly by increasing antioxidant capacity and DNA repair.