Low-Volume Exercise Training Does Increase Interleukin-17 Gene Expression But Does Not Alter Inflammation in Adipose Tissue of Mice on a High-Fat Diet

Background: Exercise is considered to have anti-inflammatory effects, yet it is unknown if moderate exercise is robust enough to exert a posi-tive influence in the face of an obesigenic diet. We aimed to determine the effects of an 8 wk low-volume exercise training protocol on visceral adipose tissue inflammatory and immune markers in mice on a 60% fat diet. Methods: Male C57Bl6/J mice (n=8/grp) were randomized to 1 of 4 groups: low-fat diet (10% fat)/sedentary (LF/Sed), LF/exercise (LF/Ex), high-fat (60% fat)/Sed (HF/Sed), or HF/Ex for 8 wks. Exercise training consisted of treadmill running 5 d/wk at 13 m/min, 5% incline, 40 min/d. Gene expression of inflammatory and immune markers was performed with quantitative real-time PCR. Results: The HF diet increased body weights, epididymal fat pads and gene expression of interleukin (IL)-10 (5.5 fold), IL-1Ra (39 fold), IL-1beta (3 fold), tissue growth factor (TGF)-beta (2.9 fold), forkhead box p3 (FOXp3) (3.2 fold), and tumor necrosis factor (TNF)-alpha (3.9 fold) (p<0.001) over the LF diet, with no exercise/diet interaction effects. Exercise increased IL-17F (2.1 fold) (p<0.05), but there was no effect of diet. Conclusions: The low-volume exercise training did not prevent or alter the general inflammatory effects of the obesigenic diet. It is possible that moderate exercise has little or no effect on visceral adipose inflammation responses suggesting that a higher volume of exercise training may be needed to exert an anti-inflammatory effect against such a diet.