The effect of regional adipose tissue depots and endocrinic adipose regulating hormones on serum leptin concentration

Objective To investigate the relationship between serum leptin concentration and regional adipose tissue depots as well as endocrinic adipose regulating hormones in Chinese. Methods 150 subjects with normal glucose tolerance were divided into three groups: non overweight, overweight and obese groups according to WHO obesity classification criteria in 1998. Regional adipose tissue depots, including visceral adipose tissue area, abdominal and femoral subcutaneous adipose tissue area were determined by magnetic resonance imaging. Meanwhile endocrinic adipose regulating hormones such as fasting serum leptin, insulin, cortisol (F), growth hormone (GH), dehydroepiandrosterone sulfate, total and free testosterone were measured. Results (1)Serum leptin level was elevated in overweight or obese subjects, and it was higher in women than that in men. (2)There was a sexual difference in the effect of body fat on leptin. In men, the correlation coefficientbetweenleptin and abdominal subcutaneous adipose tissue depot was most significant (r=0.75, P0.001). However leptin was remarkably correlated with body mass index in women (r=0.65,P0.001). (3)Insulin was an important factor independent of body fat depots in regulating serum leptin level. (4)Free testosterone was involved in the regulation of leptin, and its influence was different in sex subgroups. Conclusion Subcutaneous adipose is a factor of regional body fat that affects serum leptin concentration. Insulin and androgen are also involved in the regulation of leptin.