The role of adiponectin multimers in anorexia nervosa

Anorexia nervosa (AN) continues to be a refractory disease because of its unknown pathogenesis. The role of adiponectin in AN has not been clarified. Moreover, few reports have described the relations between adiponectin isoforms and AN in the physical and psychological states. Therefore, we measured plasma adiponectin and its isoforms levels in patients with AN to examine their roles in AN.

Eighteen women participated in this study: nine patients with AN and nine age-matched healthy controls. We examined plasma adiponectin and its isoforms levels in all subjects and administered three types of psychological test to patients with AN: the Eating Disorders Inventory-2, the Maudsley Obsessional-Compulsive Inventory, and the Beck Depression Inventory-2.

We found that the percentage of high-molecular-weight (HMW) to total adiponectin (%HMW) was significantly low and the percentage of low-molecular-weight (LMW) to total adiponectin (%LMW) was significantly high in the AN group compared with the control group. The %HMW positively and the %LMW negatively correlated with body mass index in the entire study population. The %HMW was also positively correlated with psychological symptoms such as social insecurity or cleaning evaluated with the Eating Disorders Inventory-2 or the Maudsley Obsessional-Compulsive Inventory.

Our study indicates that all adiponectin isoforms should be evaluated in patients with AN in addition to total adiponectin. The decreased %HMW and the increased %LMW that were correlated with the body mass index and some components of psychopathology in our patients may indicate a complex role of adiponectin isoforms in maintaining energy homeostasis and emotion during extreme malnourishment.