Effects of moderate exercise on cigarette smoke exposure-induced hippocampal oxidative stress values and neurological behaviors in mice

The objective of the present study was to investigate the effects of exercise training on behavior and neurochemical parameters in mice exposed to cigarette smoke. To this aim, mice (C57 BL6) male (30-35 g) were exposed to cigarette smoke 60 consecutive days three times a day and they were subjected to treadmill training 8 weeks for 5 days/week. For behavior assessment, mice were tested in the open-field and forced to a swim test. The superoxide anion, thiobarbituric acid reactive substances and protein carbonyl formation were measured as markers of oxidative stress in hippocampus of mice. In addition, the brain-derived neurotrophic factor (BDNF) levels were measured in the hippocampus samples. Cigarette smoke group and cigarette smoke plus exercise group, increased immobility time in forced swimming test in rats compared to the control group, without affecting spontaneous locomotor activity. There was an increase in the levels of superoxide, TBARS and of protein carbonyl and a decreased in BDNF levels in the hippocampus of rats exposed to cigarette smoke and cigarette smoke plus exercise. Exercise alone did not change any of the parameters evaluated in this study. In conclusion, we observed that physical training improves the oxidative stress parameters, but does not alter depressive-like behavior neither prevent the decreases in BDNF levels in hippocampus induced by cigarette smoke.