Altered immunoreactive levels of G proteins in peripheral mononuclear cells of patients with anorexia nervosa and bulimia nervosa

Alterations of cellular G proteins have been implicated in the pathophysiology of some psychiatric disorders. So far, no study assessed G protein function in anorexia nervosa (AN) and bulimia nervosa (BN). Therefore, we measured immunoreactive levels of Gαs, Gαi, Gαq/11 and Gβ protein subunits in mononuclear leukocytes of 71 drug-free women, including 25 subjects with AN, 26 individuals with BN and 20 healthy controls. As compared to healthy women, anorexic patients exhibited significantly increased levels of Gαi and Gβ proteins, while bulimic patients had significantly increased levels of Gαs, Gαi and Gβ proteins. Immunoreactive levels of peripheral G protein subunits were not significantly correlated with demographic or nutritional parameters. These findings, although obtained in peripheral blood cells, may suggest a derangement of G protein-mediated signal transduction in the pathophysiology of eating disorders.