A recent study published in the Journal of Nutrition has found that the branched chain amino acid L-isoleucine has a remarkable effect on obese mice. The researchers found that supplementation with L-isoleucine improved the glucose-lowering effects of insulin, reduced fat deposits and increased fat metabolism.
Mice were fed a very high fat diet for the entire duration of the 6 week trial. After the first 2 weeks, the mice were divided into 2 groups. One group had L-isoleucine added to their drinking water, the other did not. The results were quite impressive:
Those mice who drank water containing 2.5% isoleucine had:
- 49% less epididymal white adipose tissue (WAT) or the type of fat designed to store energy,
- Almost 6% less weight gain at the end of the study,
- 38% less fat in the liver
- 47% less fat in the skeletal muscles &
- 39% less insulin resistance
There was also a decrease in the amount of leptin, the hunger hormone, in the WAT of those mice who received L-isoleucine supplementation and an increase in some other metabolic parameters in the liver and skeletal muscle which influence healthy metabolism.
The researchers concluded that L-isoleucine may be of use in the treatment of metabolic syndrome in humans and called for clinical trials to further investigate this.
More Information:
Nishimura J, Masaki T, Arakawa M, Seike M, Yoshimatsu H. Isoleucine prevents the accumulation of tissue triglycerides and upregulates the expression of PPARalpha and uncoupling protein in diet-induced obese mice. J Nutr. 2010 Mar;140(3):496-500. Epub 2010 Jan 20 http://jn.nutrition.org/cgi/content/abstract/140/3/496 http://www.ncbi.nlm.nih.gov/pubmed/20089773