Elevated cannabinoid 1 receptor mRNA is linked to eating disorder related behavior and attitudes in females with eating disorders

Objective: The endocannabinoid system is involved in the regulation of appetite, food intake and energy balance. Methods: To study possible differences in CB(1) and CB(2) mRNA expression in eating disorders, 20 patients with anorexia nervosa (AN), 23 with bulimia nervosa (BN) and 26 healthy women were enrolled into the trial (Homocysteine and Eating Disorders, HEaD). Results: We found significantly higher levels of CB, receptor mRNA in the blood of patients with AN (Delta CT: -3.9 (1.0); KW: 11.31; P = 0.003) and BN (Delta CT -3.7 (1.7)) when compared to controls (Delta CT. -4.6 (0.6); Dunn's test AN vs. Controls: P < 0.05; BN vs. Controls: P < 0.001) measured by quantitative real-time PCR. No differences were found regarding the expression of CB(2) receptor mRNA. Higher CB(1) receptor expression was associated with lower scores in several eating disorder inventory-2 (EDI-2) subscales including perfectionism, impulse regulation and drive for thinness. Conclusion: Our finding of elevated CB(1)-receptor expression in AN and BN adds further evidence to the hypothesis of impaired endocannabinoid signaling in eating disorders. (C) 2008 Elsevier Ltd. All rights reserved.