Aerobic training reduces immune cell recruitment and cytokine levels in adipose tissue in obese mice.

Abstract

Obesity is associated with an energy imbalance that results from excessive energy intake, low diet quality and a sedentary lifestyle. In this regard, the increased consumption of a high-refined carbohydrate diet (HC) is strongly related to higher adiposity and low-grade inflammation. Aerobic training is a well-known non-pharmacological intervention to treat obesity and metabolic disturbances. However, the mechanisms through which aerobic training ameliorates the low-grade inflammation induced by the HC diet need to be further investigated. Herein, our hypothesis was that aerobic training would decrease the recruitment of leukocytes in the adipose tissue thereby reducing the levels of cytokines and improving metabolism in mice fed the HC diet. Male Balb/c were assigned to the following groups: control non-trained (C-NT), control trained (C-T), HC-NT and HC-T. Mice were submitted to moderate-intensity training sessions that consisted of running 60 min/day for 8 weeks. The intravital microscopy technique was performed in vivo in anesthetized mice to visualize the microvasculature of the adipose tissue. The HC diet induced obesity and increased the influx of immune cells into the adipose tissue. In contrast, HC-T mice presented a lower adiposity and adipocyte area. Furthermore, HC-T mice showed an increased resting energy expenditure, a decreased recruitment of immune cells in the adipose tissue, reduced cytokine levels, and ameliorated hyperglycemia and fatty liver deposition relative to HC-NT mice. Collectively, our data enhance the understanding about the antiinflammatory effect of aerobic training and shed light on the adipose tissue-mediated mechanisms by which training promotes a healthier metabolic profile.