The endocannabinoid system: body weight and metabolic regulation.
The endocannabinoid system elicits multiple physiologic functions that are not fully understood. Antagonism of cannabinoid type 1 (CB(1)) receptors has been the only successful new pharmacologic treatment approach in Phase III studies in obesity in the last 8 years. Whereas antagonism of (CB(1)) receptors acutely reduces food intake, the long-term effects on weight reduction and metabolic regulation appear to be mediated by stimulation of energy expenditure and by peripheral effects related to liver, skeletal muscle, adipose tissue, and pancreas physiology. For example, in the liver, lipogenic enzymes and fatty acid synthesis are upregulated by endocannabinoids, and in adipose tissue, antagonism of (CB(1)) receptors increases secretion of adiponectin. Some studies suggest that endocannabinoid formation is increased in obesity, perhaps because endocannabinoid degradation is decreased. Although many questions remain unanswered at present, the emerging concept of endocannabinoids as metabolic regulators helps to explain the success of rimonabant (SR141716), an antagonist of (CB(1)) receptors, currently in Phase III studies.
Engeli
Stefan
S
Franz Volhard Clinical Research Center, University Clinic Charité Campus Buch, Humboldt University of Berlin, Wiltbergstrasse 50, 13125 Berlin, Germany. stefan.engeli@charite.de
Jordan
Jens
J
D019440:Anti-Obesity Agents / Q000627:therapeutic use; D001835:Body Weight / Q000502:physiology*; D063385:Cannabinoid Receptor Modulators / Q000037:antagonists & inhibitors / Q000378:metabolism*; D063388:Endocannabinoids; D006801:Humans; D009765:Obesity / Q000188:drug therapy / Q000378:metabolism* / Q000503:physiopathology; D011379:Prognosis
D019440:Anti-Obesity Agents; D063385:Cannabinoid Receptor Modulators; D063388:Endocannabinoids