Swimming in cold water reduces the volume of fat cells, through the increase of FGF۲۱ and UCP۱ in adipose tissues

Fibroblast growth factor-۲۱ (FGF۲۱) has been identified as a potent metabolic that is released from various tissues, including white (WAT) and brown (BAT) adipose tissue in response to cold and exercise. FGF۲۱ led to increased UCP۱ that can play an important role in thermogenesis and prevent and treat overweight and obesity.Twenty male Wistar rats were randomly divided into four equal groups: Thermoneutrality-Untrained (TUN, ۲۵˚C), Cold exposure-Untrained (CUN, ۴˚C), Thermoneutrality-Trained in thermo-neutral water (TTN, ۳۰˚C), and Thermoneutrality-Trained in cold water (TTC, ۱۵˚C). The swimming included ۲-۳ min intervals, ۱ min rest, until exhaustion, three days a week for six weeks, with ۳ to ۶% bodyweight training load. Rats were exposed to cold for ۲ hours per day, five days per week. The expression of UCP۱ and FGF۲۱ protein levels were determined in BAT and WAT. In addition, FGF۲۱protein was measured in serum.The interventions resulted in lower body weight gain, associated with reduced BAT and WAT diameter; the most significant changes were observed in the TTC group. Swimming in tepid and cold water significantly increased FGF۲۱ protein in WAT and BAT compared to both untrained groups. Still, it only increased significantly in the TTC group compared to the TUN group. UCP۱ mRNA in the TTC group increased significantly compared to the other groups. Also, there was a large negative correlation between adipocyte caliber with concentration of FGF۲۱ in BAT (r=-۰.۷۸, p=۰.۰۰۳), WAT (r=-۰.۸۵, p=۰.۰۰۱), and serum (r=-۰.۷۸, p=۰.۰۰۳).The finding demonstrates swim training, and cold exposure interacts in their effects on activates expression of UCP۱ in BAT and WAT via the increased FGF۲۱ levels. According to findings, the more significant reduction in BAT and WAT diameter and lower body weight gain in the TTC group; thus, interval swimming in cold water is recommended for weight loss.

کلیدواژه ها:

brown adipose tissue ، Exercise to exhaustion ، Cold stress ، Lose weight