Alpha-2-glycoprotein, also known as AZGP1, belongs to the MHC class I family. It can be detected in body fluids such as serum, sweat, and seminal and breast cyst fluids. It has been shown that alpha-2-glycoprotein can stimulate lipolysis by adipocytes in vivo and in vitro. Thus it is believed that alpha-2-glycoprotein plays an important role in the regulation of body weight, and age-dependent changes in genetically influenced obesity, and it also regulates melanin production by normal and malignant melanocytes. Alpha-2-glycoprotein is produced by both white and brown fat adipocytes and may act in a local autocrine fashion in the reduction of adiposity in cachexia.