The Fire of Life

Science's STKE  06 Aug 2002:
Vol. 2002, Issue 144, pp. tw288-TW288
DOI: 10.1126/stke.2002.144.tw288

Why do some people gain weight readily and others stay lean no matter what they eat? An old hypothesis attributes this to interindividual variability in diet-induced thermogenesis (DIT), the heat generated in response to food ingestion. DIT is thought to be mediated by the sympathetic nervous system and stimulation of β-adrenergic receptors (βARs) on thermogenically active target tissues. Bachmann et al. (see the Perspective by Dulloo) have now tested this hypothesis by generating mice that lack the three known βARs, a genetic manipulation that should incapacitate DIT. These mutant mice become massively obese when placed on a high-fat diet. Thus, at least in rodents, DIT is indeed an important component of the body's defense against obesity.

E. S. Bachman, H. Dhillon, C.-Y. Zhang, S. Cinti, A. C. Bianco, B. K. Kobilka, B. B. Lowell, βAR signaling required for diet-induced thermogenesis and obesity resistance, Science 297, 843-845 (2002). [Abstract] [Full Text]

A. G. Dulloo, A sympathetic defense against obesity, Science 297, 780-781 (2002). [Summary] [Full Text]