Section IV: Lipid Modulators of Islet Function Update on Adipocyte Hormones Regulation of Energy Balance and Carbohydrate/Lipid Metabolism

Hormones produced by adipose tissue play a critical role in the regulation of energy intake, energy expenditure, and lipid and carbohydrate metabolism. This review will address the biology, actions, and regulation of three adi-pocyte hormones—leptin, acylation stimulating protein (ASP), and adiponectin—with an emphasis on the most recent literature. The main biological role of leptin ap-pears to be adaptation to reduced energy availability rather than prevention of obesity. In addition to the well-known consequences of absolute leptin deficiency, subjects with heterozygous leptin gene mutations have low circulating leptin levels and increased body adiposity. Leptin treatment dramatically improves metabolic abnor-malities (insulin resistance and hyperlipidemia) in pa-tients with relative leptin deficiency due to lipoatrophy