Novel role of cholesteryl ester transfer protein (CETP): attenuation of adiposity by enhancing lipolysis and brown adipose tissue activity

Abstract

Objective: The systemic function of CETP has been well characterized. CETP plasma activity reduces HDL cholesterol and thus increases the risk of atherosclerosis. Here, we investigated whether CETP expression modulate adiposity. Methods: Body adiposity and energy metabolism related assays and gene/protein expression were compared in CETP transgenic and non-transgenic mice and in hamsters treated with CETP neutralizing antibody. Results: We found that transgenic mice expressing human CETP present less white adipose tissue mass and lower leptinemia than nontransgenic (NTg) littermates. No differences were found in physical activity, food intake, fat fecal excretion, lipogenesis or exogenous lipid accumulation in adipose depots. Nonetheless, adipose lipolysis rates and whole-body energy expenditure were elevated in CETP mice. In accordance, lipolysis-related gene expression and protein content were increased in visceral and brown adipose tissue (BAT). In addition, we verified increased BAT temperature and oxygen consumption. These results were confirmed in two other animal models: 1) hamsters treated with CETP neutralizing antibody and 2) an independent line of transgenic mice expressing simian CETP. Conclusions: These findings reveal a novel anti-adipogenic role for CETP.