Brain administration of leptin causes deletion of adipocytes by apoptosis.

Leptin, produced in adipocytes, works through the central nervous system (CNS) to modulate food intake and energy expenditure, resulting in rapid loss of body fat depots. It is now shown that this process includes adipocyte apoptosis. Adipocyte deletion by apoptosis occurred after intracerebroventricular (i.c.v.) administration of leptin in rats. Adipose tissue of leptin-treated rats demonstrated characteristic features of apoptosis, including internucleosomal fragmentation of genomic DNA, elevated levels of DNA strand breaks and a reduction in total DNA content and cellular volume. These apoptotic features were absent in control and pair-fed rats and in other tissues of leptin-treated rats.