Effects of Hypoxia and Hypoxic Training on 8-Hydroxydeoxyguanosine and Glutathione Levels in the Liver

The effects of hypoxia and hypoxic training on 8-hydroxydeoxyguanosine (8-OHdG), reduced glutathione (GSH), and oxidized glutathione (GSSG) levels and on glutathione reductase (GR) activity in the liver of rats were evaluated. Rats were divided into 3 groups: a hypoxia and exercise (HE) group, a hypoxia and sedentary (HS) group, and a normoxia and sedentary (NS) group. The liver 8-OHdG levels were lower in the HE and HS groups compared with the NS group (P < .05). No significant difference between in the liver 8-OHdG levels in the HE and HS groups were found. However, the liver GSH level in the HS group was lower than that in the NS group (P < .05), and the HE group had significantly higher levels of liver GSH than the HS group (P < .01). The activity of liver GR in the HS group was lower than that of the NS group (P < .05). Moreover, the liver GR activity of the HE group was significantly higher than that of the HS group (P < .01). No significant difference in liver GR activity between the HE and NS groups was noted. In conclusion, the present study confirmed that moderate hypoxia and hypoxic training attenuated liver DNA damage and decreased liver GSH levels and GR activity. These results indicate that moderate hypoxia and hypoxic training result in decreased oxidative stress.