Newfound Mechanism Rewires Cellular Energy Processing for Drastic Weight Loss

Mice genetically engineered to lack the ability to make the amino acid cysteine, and fed a cysteine-free diet, lost 30 percent of their body weight in just one week, a new study shows. Published online May 21 in Nature, the work shows that cysteine depletion disrupts the normal metabolic pathways used by mammalian cells to convert food into energy, forcing the animals to rapidly burn fat stores in a futile attempt to meet energy demands. Led by researchers at NYU Grossman School of Medicine, the study reveals key details about how cells process fuels like carbohydrates and fats (metabolism), and how cysteine depletion affects tissues. Experiments showed that lowering cysteine levels caused a drop in levels of the co-factor coenzyme A (CoA), which rendered inefficient the mechanisms that convert carbohydrates and fats into energy. Despite CoA being involved in more than 100 intermediate metabolic reactions and serving as a partner (co-factor) for 4 percent of all enzymes in the body, ... Read full article.