The effect of aerobic exercise training on gene expression of beta3-adrenergic receptor and beta-arrestin2 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. Beta3- adrenergic receptor (Adrb3) and beta-arrestin2 (Barr2) are pivotal agents in the beta-adrenergic-signaling pathway. This study aimed to investigate the preventive effect of aerobic training on dysregulation of Adrb3 and Barr2 gene expression that was induced by high-fat diet (HFD) in inguinal white adipose tissue of mice. Materials and Methods: Twenty-one C57BL/6 mice were assigned to three groups as follows: 1) control group (n=7), 2) high-fat diet-induced overweight (HFD-OW) (n=7), and 3) high-fat diet with aerobic training (HFD-AT) (n=7). The HFD-OW group were fed with a HFD for 12 weeks. The HFD-AT group had aerobic training for six weeks on a treadmill in addition to feeding with the HFD. The real-time polymerase chain reaction (PCR) method was used to measure the gene expression of Adrb3 and Barr2 in inguinal white adipose tissue. Results: The gene expression of Adrb3 did not significantly change between groups (P>0.05). However, the expression of Barr2 in HFD-OW group was significantly increased as compared to the control group (1.5-fold: P=0.001). Interestingly, the Barr2 expression in HFD-AT group was significantly lower compared with HFD-OW group (P=0.045). Conclusion: The results indicated that aerobic training could inhibit the upregulation of Barr2 induced by HFD. It seems that a portion of the preventive effect of aerobic training on the development of obesity may be mediated by inhibiting the Barr2 expression in adipose tissue.