Burning fat with cysteine depletion

Adams and colleagues comment on two complementary articles by Varghese et al and Lee et al showing that cysteine depletion through combined dietary and genetic means in mice evokes a unique stress response in the liver to amplify these metabolic outcomes and offer a potentially new treatment option for obesity.

A purinergic call to arms from dying brown adipocytes

Brown adipocytes react to temperature and nutritional challenges by ramping up their metabolism and generating heat. This adaptation to changes in the environment is crucial for defending organismal homeostasis, but is impaired in obesity and during aging. Writing in Nature, Niemann et al. show that brown adipocytes become apoptotic under thermoneutral conditions and release ATP, which in turn is converted extracellularly into inosine. They further present evidence that pharmacological and genetic manipulations that enhance signalling of this purine metabolite stimulates thermo-genesis in brown adipocytes and promotes metabolic health.