Whole body protein metabolism in children with cancer

• Published in: Archives of disease in childhood Vol. 75; no. 4; pp. 273 - 281
• Main Authors: Daley, S E, Pearson, A D, Craft, A W, Kernahan, J, Wyllie, R A, Price, L, Brock, C, Hetherington, C, Halliday, D, Bartlett, K
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health 01.10.1996; BMJ; BMJ Publishing Group LTD
• Subjects: Adolescent; Amino acids; Amino Acids - blood; Biological and medical sciences; Cancer; Carbon Isotopes; Child; Child, Preschool; Deuterium; Female; Humans; Kinetics; Leucine; Male; Medical sciences; Metabolites; Multiple tumors. Solid tumors. Tumors in childhood (general aspects); Neoplasms - blood; Neoplasms - metabolism; Phenylalanine; Protein Biosynthesis; Protein synthesis; Proteins - metabolism; Tracer techniques; Tumors; Tyrosine - metabolism; Human; Proteins; Protein synthesis; Turnover; Exploration; Catabolism; Whole body; Malignant tumor; Metabolism; Child; Isotopes
• ISSN: 0003-9888; 1468-2044
• DOI: 10.1136/adc.75.4.273

Whole body protein synthesis and catabolism were measured using the [ring-2H5]phenylalanine and [1-13C]leucine primed constant infusion technique in 32 paediatric patients with cancer at different stages of treatment. Rates of synthesis (S) and catabolism (C) derived from the [ring-2H5]phenylalanine and [1-13C]leucine models were 4.7 (SD 1.3) (S) and 6.0 (1.5) (C) g/d/kg, and 5.5 (0.8) (S) and 6.8 (1.2) (C) g/d/kg, respectively. These results show that these two tracer techniques give similar results in this study population. Comparison of these values with results previously reported for groups of control children using the [ring-2H5]phenylalanine model (S = 3.69 and 3.93; C = 4.09 and 4.28 g/d/kg) and the [1-13C]leucine model (S = 4.32; C = 4.85 g/d/kg) show that rates of synthesis and catabolism were higher in cancer patients than in controls. Thus whole body protein turnover is increased in children under treatment for cancer. Other indices of metabolism such as plasma amino acids and intermediary metabolites were also measured and showed that, although subjects were in isotopic steady state, there were significant metabolic changes during the course of the primed constant infusions used to measure protein turnover.