METABOLIC AND REGULATORY EFFECTS OF BRANCHED-CHAIN AMINO-ACID SUPPLEMENTATION

This review specifically examines the various roles of the supplementation of branched chain amino acids (BCAA) in general and leucine in particular. These amino acids have been shown to have variable effects under different experimental dietary conditions. The branched chain amino acids have a special role in nitrogen metabolism both in the fasting state when they provide the brain with an energy source and after feeding when they are extracted predominantly by muscle to provide important source of energy as well as nitrogen, Supplementation of leucine also affects tryptophan niacin pathway which further depends upon the dietary intake of vitamin B-6. Moreover, leucine supplementation with low protein diet has been shown to be protein catabolic while with adequate protein diet it has been shown to promote growth. Branched chain amino adds have also been used in the treatment oi certain protein catabolic states. Besides, leucine supplementation has also been shown to affect the secretion of prolactin and insulin. These data suggest that BCAA not only act as a precursors for several metabolic reactions but are also important biochemical regulators.