Deranged endocannabinoid responses to hedonic eating in underweight and recently weight-restored patients with anorexia nervosa

Am J Clin Nutr. 2015 Feb;101(2):262-9. doi: 10.3945/ajcn.114.096164. Epub 2014 Dec 10.

Abstract

Background: A dysregulation of reward mechanisms was suggested in the pathophysiology of anorexia nervosa (AN), but the role of the endogenous mediators of reward has been poorly investigated. Endocannabinoids, including anandamide and 2-arachidonoylglycerol, and the endocannabinoid-related compounds oleoylethanolamide and palmitoylethanolamide modulate food-related and unrelated reward. Hedonic eating, which is the consumption of food just for pleasure and not homeostatic need, is a suitable paradigm to explore food-related reward.

Objective: We investigated responses of endocannabinoids and endocannabinoid-related compounds to hedonic eating in AN.

Design: Peripheral concentrations of anandamide, 2-arachidonoylglycerol, oleoylethanolamide, and palmitoylethanolamide were measured in 7 underweight and 7 weight-restored AN patients after eating favorite and nonfavorite foods in the condition of no homeostatic needs, and these measurements were compared with those of previously studied healthy control subjects.

Results: 1) In healthy controls, plasma 2-arachidonoylglycerol concentrations decreased after both types of meals but were significantly higher in hedonic eating; in underweight AN patients, 2-arachidonoylglycerol concentrations did not show specific time patterns after eating either favorite or nonfavorite foods, whereas in weight-restored patients, 2-arachidonoylglycerol concentrations showed similar increases with both types of meals. 2) Anandamide plasma concentrations exhibited no differences in their response patterns to hedonic eating in the groups. 3) Compared with 2-arachidonoylglycerol, palmitoylethanolamide concentrations exhibited an opposite response pattern to hedonic eating in healthy controls; this pattern was partially preserved in underweight AN patients but not in weight-restored ones. 4) Like palmitoylethanolamide, oleoylethanolamide plasma concentrations tended to be higher in nonhedonic eating than in hedonic eating in healthy controls; moreover, no difference between healthy subjects and AN patients was observed for food-intake-induced changes in oleoylethanolamide concentrations.

Conclusion: These data confirm that endocannabinoids and endocannabinoid-related compounds are involved in food-related reward and suggest a dysregulation of their physiology in AN. This trial was registered at ISRCTN.org as ISRCTN64683774.

Keywords: anhedonia; anorexia nervosa; endocannabinoids; hedonic eating; reward.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Amides
  • Anorexia Nervosa / blood
  • Anorexia Nervosa / complications
  • Anorexia Nervosa / physiopathology*
  • Arachidonic Acids / blood
  • Case-Control Studies
  • Endocannabinoids / blood*
  • Energy Intake
  • Ethanolamines / blood
  • Female
  • Glycerides / blood
  • Healthy Volunteers
  • Humans
  • Male
  • Meals
  • Oleic Acids / blood
  • Palmitic Acids / blood
  • Polyunsaturated Alkamides / blood
  • Retrospective Studies
  • Reward
  • Thinness / blood
  • Thinness / complications
  • Thinness / physiopathology*
  • Young Adult

Substances

  • Amides
  • Arachidonic Acids
  • Endocannabinoids
  • Ethanolamines
  • Glycerides
  • Oleic Acids
  • Palmitic Acids
  • Polyunsaturated Alkamides
  • oleoylethanolamide
  • palmidrol
  • glyceryl 2-arachidonate
  • anandamide

Associated data

  • ISRCTN/ISRCTN64683774