The Role of Leptin in Obese Children

The obesity gene (ob) in mice encodes a protein produced by adipose tissue, leptin, which regulates body weight (3). Under experimental conditions, leptin affects the central nervous system and tends to reduce appetite and increase energy expenditure. Numerous studies have shown an increased expression of the ob gene (mRNA-leptin) in adipocytes or a marked increase in serum leptin concentration of obese subjects relative to lean subjects; a positive correlation with the body mass index has been reported (4,5). Leptin also exerts various effects on metabolism, glucose homeostasis and sexual development and activity. It has been reported that leptin serum levels do not merely reflect adipose tissue size but that they play in controlling of body weight homeostasis and fatness development. Some of these studies will be analyzed in this review, because the role for leptin to predict weight gain is still controversial.