Effects of exercise training on gingival oxidative stress in obese rats

Abstract

ObjectiveThe purpose of the present study was to investigate the effects of exercise training on serum reactive oxygen species (ROS) level and gingival oxidative stress in obese rats fed a high-fat diet. DesignRats were divided into three groups (n=14/group): one control group (fed a regular diet) and two experimental groups (fed a high-fat diet with and without exercise training [treadmill: 5 days/week]). The rats were sacrificed at 4 or 8 weeks. The level of serum reactive oxidative metabolites (ROM) was measured as an indicator of circulating ROS. The level of 8-hydroxydeoxyguanosine (8-OHdG) and reduced-form glutathione (GSH)/oxidised-form glutathione (GSSG) ratio were determined to evaluate gingival oxidative stress. ResultsThe obese rats fed a high-fat diet without exercise training showed higher serum ROM levels [Carratelli Units (CARR U)] (mean±SD; 413±64) than the control (333±12) at 4 weeks (p=0.023). Such a condition resulted in higher 8-OHdG levels (ng/mg mtDNA) (0.97±0.18) (p<0.05) and a lower GSH/GSSG ratio (17.0±3.1) (p<0.05) in gingival tissues, compared to the control (0.55±0.13 for 8-OHdG and 23.6±5.8 for GSH/GSSG ratio) at 8 weeks. In addition, the obese rats fed a high-fat diet with exercise training showed lower serum ROM (623±103) (p<0.001) and gingival 8-OHdG levels (0.69±0.17) (p=0.012) than those without exercise training (1105±95 for ROM and 0.55±0.13 for 8-OHdG) at 8 weeks. ConclusionsObesity prevention by exercise training may effectively suppress gingival oxidative stress by decreasing serum ROS in rats.