Plasma omentin-1 levels are related to exercise performance in obese women and increase upon aerobic endurance training

INTRODUCTION: Omentin-1 is an adipokine that is primarily released from visceral adipose tissue stromal cells. The effects of exercise on omentin-1 regulation are not clear so far. Therefore, the effect of endurance training on circulating omentin-1 levels and its relation to exercise performance was assessed in obese women.

METHODS: 13 obese women (age: 44.8±3.3 years; BMI: 37.8±1.3 kg·m(-2)) participated in a 6-week endurance training program. Omentin-1, metabolic traits (glucose, insulin, HOMA-IR, lipids profile), and exercise performance (cardiopulmonary exercise test (V̇O2,peak, Wpeak), 6 min walking test, 6MWT) were assessed before and after the training.

RESULTS: After the training program circulating omentin-1 were 10.4% higher than before the program (690±50 ng·ml(-1) vs. 618±42; p=0.04), while body weight remained unchanged (p=0.9). Before training, omentin-1 levels were significantly correlated with Wpeak (given in absolute and relative values) as well as with 6MWT (all r≥0.603; all p≤0.029) and the correlations with absolute as well as relativeV̇O2,peak approached significance (both r≥0.534; both p≤0.060). After training, respective correlations were generally weaker and did not reach significance any longer (all r≤0.465; all p≥0.109). Neither before nor after the training program were significant correlations found between omentin-1 levels and the other measured metabolic blood markers (all p≥0.157).

DISCUSSION: Data show a rather strong relationship between exercise performance and circulating omentin-1 levels as well as an increase of the adipokine in response to 6-week of endurance training in obese women. Our findings may hint to a skeletal muscle-adipose tissue crosstalk in regard of omentin-1 regulation.