Reid, Marvin E.; Forrester, Terrence E. ; Badaloo, Asha V.; Heird, William C.; Jahoor, Farook
Author Affiliation, Ana.
Tropical Medicine Research Institute
Supplementation with aromatic amino acids improves leucine kinetics but not aromatic amino acid kinetics in infants with infection, severe malnutrition, and edema 1,2
Journal of Nutrition
Date of Publication
The study investigated whether supplementation with an aromatic amino acid (AAA) cocktail consisting of 0.5 mmol each of phenylalanine, tryptophan, and tyrosine compared with isonitrogenous amounts of alanine (Ala0 would improve measures of protein kinetics in 14 (8 with AAA, 6 Ala) children with edematous malnutrition (aged 6-24 mo) during the infected acute malnourished state. Supplementation started immediately after the basline experiment, 2 d posadmission and continued to the end of the acute phase of treatment. The second (post-supplementation) experiment was done 12 d post admission. We measured leucine kinetics, phenylalanine and tyrosine fluxes, using an i.g 8-h prime continuous infusion of ^ sup 2 ^ H ^ sub 3 ^- leucine, and an i.v 6-h prime continuous infusion of ^ sup 13 ^ C- leucine , ^ sup 2 ^ H ^ sub 2 ^ -tyrosine, and ^ sup 2 ^ H ^ sub 5 ^ - phenylalanine in the fed state. Leucine flux tended to be faster (P = 0.06) in the AAA group compared with Ala group after supplementation (mean difference ▒ SEM): 22.6 ▒ 10.9 Ámol/ (kg. h). The rate of leucine appearance from protein breakdown [28.1▒ 9.4Ámol/ (kg. h] and the nonoxidative disposal of leucine [i.e., leucine ot protein synthesis; 35.4 ▒ 12.9 Ámol/ (kg. h) were faster (P < 0.02) in the AAA group that in the Ala group. There was no significant effect of supplementation on leucine splanchin metabolism, phenylalanine, and tyrosine fluxes. These findings are consistent with the hypothesis that the blunting of the protein catabolic response to infection in children with edematous malnutrition syndrome is due to limited availability of aromatic amino acids.....