Effects of acute endurance exercise on follistatin-like 1 and apelin in the circulation and metabolic organs in rats.

Context: Follistatin-like 1 (FSTL1) and apelin exert a favourable effect on energy metabolism. Objective: We examined the effects of acute endurance exercise on the levels of FSTL1 and apelin in the serum and metabolic organs of rats. Methods: Rats were divided into two groups: a sedentary control (CON, n  = 8) group and exercise (EX, n  = 8) group. The EX group was made to run on a treadmill at 15-30 m/min for 35 min. Immediately after exercise, the blood, skeletal muscles, adipose, heart, and liver were collected; the levels of FSTL1 and apelin were measured. Results: Serum FSTL1 and apelin were significantly increased following acute exercise; in contrast, the levels of FSTL1 and apelin in the tissues were not affected. Conclusions: Acute endurance exercise may stimulate the secretion of FSTL1 and apelin into the circulation, however, the origin of their increased secreted levels may not be the metabolic organs.