Cide proteins and the development of obesity.

Obesity has become the most prevalent chronic disorder that affects large populations throughout the world. Obesity is due largely to the imbalance between energy intake and expenditure. Energy balance is regulated by interactions between various tissues such as adipose tissues, liver and skeletal muscle. Adipose tissues, which include brown adipose tissue (BAT) and white adipose tissue (WAT), play crucial roles in maintaining energy homeostasis. While WAT stores energy in the form of triglycerides; BAT increases energy expenditure through thermogenesis. Cide proteins including Cidea, Cideb and Fsp27, are expressed at high levels in BAT, liver and WAT, respectively. Cidea(-/-) mice exhibit increased lipolysis in BAT and are resistant to high fat diet-induced obesity and diabetes. Our recent data suggest that Cideb also plays an important role in the development of obesity by regulating various metabolic pathways in liver. The molecular mechanism of Cide protein regulation of metabolic networks and obesity is discussed.