The effect of aerobic exercise training on gene expression of beta۳-adrenergic receptor and beta-arrestin۲ in inguinal white adipose tissue of mice fed with a high fat diet

Background and aims: Beta-adrenergic signaling deficiency has been established to be related to obesity and related diseases. Beta۳-adrenergic receptor (Adrb۳) and beta-arrestin۲ (Barr۲) are pivotal agents in the beta-adrenergic-signaling pathway. This study aimed toinvestigate the preventive effect of aerobic training on dysregulation of Adrb۳ and Barr۲ gene expression that was induced by high-fat diet(HFD) in inguinal white adipose tissue of mice.Materials and Methods: Twenty-one C۵۷BL/۶ mice were assigned to three groups as follows: ۱) control group (n=۷), ۲) high-fat dietinducedoverweight (HFD-OW) (n=۷), and ۳) high-fat diet with aerobic training (HFD-AT) (n=۷). The HFD-OW group were fed with aHFD for ۱۲ weeks. The HFD-AT group had aerobic training for six weeks on a treadmill in addition to feeding with the HFD. The real-timepolymerase chain reaction (PCR) method was used to measure the gene expression of Adrb۳ and Barr۲ in inguinal white adipose tissue.Results: The gene expression of Adrb۳ did not significantly change between groups (P > ۰.۰۵). However, the expression of Barr۲ in HFDOWgroup was significantly increased as compared to the control group (۱.۵-fold: P = ۰.۰۰۱). Interestingly, the Barr۲ expression in HFD-ATgroup was significantly lower compared with HFD-OW group (P = ۰.۰۴۵).Conclusion: The results indicated that aerobic training could inhibit the upregulation of Barr۲ induced by HFD. It seems that a portionof the preventive effect of aerobic training on the development of obesity may be mediated by inhibiting the Barr۲ expression in adiposetissue.