BIOLOGICAL ACTION OF LEPTIN AS AN ANGIOGENIC FACTOR

Leptin is a hormone that regulates food intake, and its receptor (OB-R b) is expressed primarily in the hypothalamus. Here, it is shown that OB-Rb is also expressed in human vasculature and in primary cultures o i human endothelial coils, In vitro and in vivo assays revealed that L eptin has angiogenic activity. In vivo, Leptin induced neovascularizat ion in corneas from normal rats but not in corneas from fa/fa Zucker r ats, which Lack functional Leptin receptors. These observations indica te that the vascular endothelium is a target for Leptin and suggest a physiological mechanism whereby Leptin-induced angiogenesis may facili tate increased energy expenditure.