Location: Children's Nutrition Research CenterTitle: Dietary supplementation with aromatic amino acids increases protein synthesis in children wHh severe acute malnutrition Author
|Hsu, Jean - Children's Nutrition Research Center (CNRC)|
|Badaloo, Asha - University Of The West Indies|
|Wilson, Lorraine - University Of The West Indies|
|Taylor-bryan, Carolyn - University Of The West Indies|
|Chambers, Bentley - University Of The West Indies|
|Reid, Marvin - University Of The West Indies|
|Forrester, Terrence - University Of The West Indies|
|Jahoor, Farook - Children's Nutrition Research Center (CNRC)|
Submitted to: Journal of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/25/2014
Publication Date: 5/1/2014
Citation: Hsu, J.W., Badaloo, A., Wilson, L., Taylor-Bryan, C., Chambers, B., Reid, M., Forrester, T., Jahoor, F. 2014. Dietary supplementation with aromatic amino acids increases protein synthesis in children wHh severe acute malnutrition. Journal of Nutrition. 144(5):660-666.
Interpretive Summary: Just after admission to a hospital, malnourished children have to be fed a relatively small amount of protein and calories that is just enough to maintain function of the organs of the body. Otherwise the children's organs will become overloaded and fail to function properly, even causing death. During this early treatment period the children do not normally gain weight or grow. However, in an earlier study we showed that adding three compounds called aromatic amino acids to the children's meals caused them to gain some weight during this early period of treatment. Aromatic amino acids are compounds that are present in the protein of our diets and they are required in large amounts to make body proteins. After this early period of treatment the malnourished child's appetite starts to improve and he/she is next placed on a high energy and protein diet and starts to grow and put on weight very rapidly. This period is called the rapid catch-up growth phase. In this study we wanted to find out whether adding extra aromatic amino acids to the children's meals during the rapid catch-up growth phase will cause the children to make body proteins faster, and therefore recover faster from their malnutrition. To answer this question the present study was conducted in children being treated for severe malnutrition. We found that children who were fed extra aromatic amino acids made body proteins faster and deposited more body protein compared to those who did not get any extra aromatic amino acids. These findings suggest that extra aromatic amino acids should be added to the meals of malnourished children during the catch-up growth phase of treatment to speed up the time taken to recover.
Technical Abstract: Although 2 earlier studies reported that aromatic amino acid (AAA) supplementation of children with severe acute malnutrition (SAM) improved whole-body protein anabolism during the early postadmission (maintenance) phase of rehabilitation, it is not known whether this positive effect was maintained during the catch-up growth and recovery phases of treatment. This study aimed to determine whether supplementation with an AAA cocktail (330 / mg · kg(-1) / d(-1)) vs. isonitrogenous Ala would improve measures of protein kinetics in 22 children, aged 4-31 mo, during the catch-up growth and recovery phases of treatment for SAM. Protein kinetics were assessed by measuring leucine, phenylalanine, and urea kinetics with the use of standard stable isotope tracer methods in the fed state. Supplementation started at the end of the maintenance period when the children were clinically/metabolically stable and continued up to full nutritional recovery. Three experiments were performed: at the end of maintenance (at approximately 13 d postadmission), at mid-catch-up growth (at approximately 23 d post- admission when the children had replenished 50% of their weight deficit), and at recovery (at approximately 48 d postadmission when they had achieved at least 90% weight for length). Children in the AAA group had significantly faster protein synthesis compared with those in the Ala group at mid-catch-up growth (101 +/- 10 vs. 72 +/- 7 umol phenylalanine / kg(-1) / h(-1); P < 0.05) and better protein balance at mid-catch-up growth (49 +/- 5 vs. 30 +/- 2 umol phenylalanine / kg(-1) / h(-1); P < 0.05) and at recovery (37 +/- 8 vs. 11 +/- 3 µmol phenylalanine / kg(-1) / h(-1); P < 0.05). We conclude that dietary supplementation with AAA accelerates net protein synthesis in children during nutritional rehabilitation for SAM.