Research into Dietary Leucine

Non-targeted biochemical profiling (metabolomics) provided insight into the biochemical mechanisms of leucine’s effects on metabolism. The study was carried out by lead investigator C. Ron Kahn, M.D. and colleagues at the Joslin Diabetes Center and Harvard Medical School and Metabolon.

The researchers evaluated the effects of leucine supplements on metabolism and insulin signaling in a mouse model of insulin resistance and metabolic syndrome. They showed that a dietary increase in leucine, a branched chain amino acid, improved glucose tolerance, prevented fatty liver, reduced obesity-induced adipose tissue inflammation and rescued insulin signaling in muscle, liver and fat. By using a global metabolic profiling approach the investigators were able to follow leucine metabolism in serum, liver, fat and muscle in the high fat diet-(HFD)-induced obesity mice. The metabolomic analysis showed leucine supplementation resulted in changes in multiple metabolic pathways involving protein, lipid and carbohydrate metabolism. Notably, leucine addition to a high fat diet restored the metabolic profile of the animals to the profile found in mice fed a control diet.

Commenting on the study, collaborator, Dr. Kahn, Head of Section on Integrative Physiology and Metabolism at the Joslin Diabetes Center and Iacocca Professor of Medicine at Harvard Medical School, said, “These findings point to the importance of even small changes in diet on metabolism and diabetes risk, and how important it is to be able to measure the full range of metabolite changes that altering the diet can affect.”

The article has been published on-line in PLoS One and may be accessed below.