Leptin as a new diagnostic tool in chronic heart failure.

Leptin, the product of the ob-gene, regulates cellular homeostasis and glycemic control. While initially described as an adipocyte-derived protein with expression and secretion restricted to adipose tissue, recent reports have shown local expression of leptin in several tissues including the skeletal muscle, heart, vessels and brain. Leptin acts through the different isoforms of its receptor which are ubiquitously expressed and can be detected in endothelium, vascular smooth muscle and myocardium. In addition to its metabolic effects, leptin has distinct effects in the cardiovascular system leading to increased production of proinflammatory cytokines and oxidative stress, vascular remodeling and neointima formation as well as cardiomyocyte hypertrophy. Notably, recent clinical studies have linked serum levels of leptin to the occurrence of cardiovascular events such as myocardial infarction and stroke suggesting that leptin promotes pro-atherogenic vascular mechanisms. In contrast, less is known about the role and effects of leptin in the setting of chronic heart failure. We here review the current knowledge on cardiovascular effects of leptin and discuss its potential as a new therapeutic tool in chronic heart failure.