Control of eating by hepatic oxidation of fatty acids. A note of caution.

Langhans [Langhans, W. (2008). Fatty acid oxidation in the energostatic control of eating-a new idea. Appetite, 51, 446-451] suggested that the liver might not be involved in the control of eating by fatty acid oxidation (FAO). However, the evidence presented against the role of the liver is weak at best, and may be incorrect. Inhibition of FAO by metabolic inhibitors generally stimulates eating, but in recent experiments from the author's laboratory, inhibition of beta-oxidation failed to stimulate eating when FAO was elevated by fasting or adrenoceptor agonists. The author used these experiments as evidence that the liver is not involved in the control of eating by FAO, but this conclusion is open to question because mercaptoacetate, the agent used to inhibit FAO, stimulates anorexia through adrenergic mechanisms. The evidence supporting a role for hepatic FAO in metabolic regulation of food intake remains strong.