Synergistic Effects of Aerobic Training and Capsaicin on FNDC5 Gene Expression and Irisin Protein Level of Visceral Adipose Tissue in Rat Fed a High-Fat Diet

Converting white adipose tissue (WAT) to brown adipose tissue (BAT) is therapeutic potential to combat obesity. The purpose of this study was to investigate the effects of aerobic training and capsaicin (Cap) on FNDC5 gene expression and irisin protein level of visceral adipose tissue in rat fed a high-fat diet (HFD).

40 male Wistar rats were fed a normal diet (ND, n = 8) or HFD (n = 32) for 8 weeks. After 8 weeks, all rats were divided into 5 groups: ND, HFD, high-fat diet-training (HFDT), high-fat diet-capsaicin (HFDCap), high-fat diet-training-capsaicin (HFDTCap). Training groups have performed a progressive aerobic running program (at 15-25 m/min, 30-60 min/day, and 5 days/week) on a motor-driven treadmill for eight weeks. Capsaicin (4 mg/kg/day) were administered orally, by gavage, once a day.

The results of this study showed that FNDC5 expression (p=0.001) and irisin (p=0.000) was decreased in HFD group compared to ND group. Also, the expression of FNDC5 and irisin in HFDT (Respectively p=0.006, p=0.020), HFDCap (Respectively p=0.005, p=0.021) and HFDTCap (Respectively p=0.000, p=0.000) groups was significantly increased compared to HFD. The expression of FNDC5 and irisin in HFDTCap was also significantly increased compared to HFDT (Respectively p=0.037, p=0.035) and HFDCap (Respectively p=0.044, p=0.033) groups.

Aerobic training combination with capsaicin with increased FNDC5 and irisin in visceral adipose tissue, had Interactive effects on factors affecting browning of adipose tissue.