Dietary essential amino acids are highly anabolic in pediatric patients with cystic fibrosis

BackgroundCurrent nutritional approaches have been partially successful in Cystic Fibrosis (CF). Essential amino acids mixtures with high Leucine levels (EAA) have anabolic properties in catabolic conditions, however data in CF are lacking.MethodsOn two days according a randomized crossover design, 15 pediatric CF patients ingested 6.7 g EAA versus mixture of total amino acids as present in whey. Whole body protein and Arginine metabolism (as EAA lack Arginine) were assessed by stable isotope methodology.ResultsProtein synthesis (P < 0.05) but not protein breakdown was higher after EAA and 70% higher values for net anabolism (P < 0.001)were found both in patients with and without nutritional failure. Arginine turnover was lower (P < 0.001) and de novo Arginine synthesis tended lower (P = 0.09) after EAA. Nitric oxide synthesis was not different.ConclusionsCF patients are highly responsive to EAA intake independent of their nutritional status. Addition of Arginine to the EAA mixture may be warranted in CF.