TY - JOUR
T1 - Whole body protein anabolism in COPD patients and healthy older adults is not enhanced by adding either carbohydrates or leucine to a serving of protein
AU - Jonker, Renate
AU - Deutz, Nicolaas E. P.
AU - Schols, Annemie M. W. J.
AU - Veley, Eugene A.
AU - Harrykissoon, Rajesh
AU - Zachria, Anthony J.
AU - Engelen, Marielle P. K. J.
N1 - Funding Information:
We sincerely thank the COPD patients and the healthy control subjects who have participated in this research and made this work possible. Furthermore, the authors thank chief analytical chemist John Thaden, PhD, for sample analysis. Funder of the research is the National Institutes of Health (Grant IDs: P30-ES023512-01; HL095903; S10-RR027047).
Publisher Copyright:
© 2018 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism
PY - 2019/8
Y1 - 2019/8
N2 - Background & aims: Carbohydrates (CHO) and leucine (LEU) both have insulinotropic properties, and could therefore enhance the protein anabolic capacity of dietary proteins, which are important nutrients in preventing muscle loss in patients with Chronic Obstructive Pulmonary Disease (COPD). LEU is also known to activate protein anabolic signaling pathways independent of insulin. Based on our previous findings in COPD, we hypothesized that whole body protein anabolism is enhanced to a comparable extent by the separate and combined co-ingestion of CHO and LEU with protein.Methods: To disentangle the protein anabolic effects of CHO and/or free LEU when co-ingested with a high-quality protein, we studied 10 patients with moderate to very severe COPD and dyspnea (GOLD: II-IV, mMRC dyspnea scale >= 2), at risk for muscle loss, and 10 healthy age- and gender-matched controls. On four occasions, in a single-blind randomized crossover design, each subject ingested a drink containing 0.6 g/kg fat-free mass (ffm) hydrolyzed casein protein with, a) no add-ons (protein), b) 0.3 g/kg ffm CHO (protein + CHO), c) 0.095 g/kg ffm leucine (protein + LEU), d) both add-ons (protein + CHO + LEU). Whole body protein breakdown (PB), protein synthesis (PS), and net protein balance (= PS - PB) were measured by IV primed and continuous infusion of L-[ring-H-2(5)]-phenylalanine and L-[C-13(9),N-15]-tyrosine. L-[N-15]-phenylalanine was added to the protein drinks to measure splanchnic extraction.Results: In both groups, whole body PS, PB and net protein balance responses were comparable between the four protein drinks, despite higher postprandial plasma LEU concentrations for the LEU supplemented drinks (P <0.05), and higher insulin concentrations for the CHO supplemented drinks as compared to the protein only drink (P <0.05).Conclusions: Adding CHO and/or LEU to a serving of high-quality protein does not further augment whole body protein anabolism in dyspneic COPD patients at risk for muscle loss or healthy older adults. Trial registry: ClinicalTrials.gov; No. NCT01734473; URL: www.clinicaltrials.gov. (C) 2018 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.
AB - Background & aims: Carbohydrates (CHO) and leucine (LEU) both have insulinotropic properties, and could therefore enhance the protein anabolic capacity of dietary proteins, which are important nutrients in preventing muscle loss in patients with Chronic Obstructive Pulmonary Disease (COPD). LEU is also known to activate protein anabolic signaling pathways independent of insulin. Based on our previous findings in COPD, we hypothesized that whole body protein anabolism is enhanced to a comparable extent by the separate and combined co-ingestion of CHO and LEU with protein.Methods: To disentangle the protein anabolic effects of CHO and/or free LEU when co-ingested with a high-quality protein, we studied 10 patients with moderate to very severe COPD and dyspnea (GOLD: II-IV, mMRC dyspnea scale >= 2), at risk for muscle loss, and 10 healthy age- and gender-matched controls. On four occasions, in a single-blind randomized crossover design, each subject ingested a drink containing 0.6 g/kg fat-free mass (ffm) hydrolyzed casein protein with, a) no add-ons (protein), b) 0.3 g/kg ffm CHO (protein + CHO), c) 0.095 g/kg ffm leucine (protein + LEU), d) both add-ons (protein + CHO + LEU). Whole body protein breakdown (PB), protein synthesis (PS), and net protein balance (= PS - PB) were measured by IV primed and continuous infusion of L-[ring-H-2(5)]-phenylalanine and L-[C-13(9),N-15]-tyrosine. L-[N-15]-phenylalanine was added to the protein drinks to measure splanchnic extraction.Results: In both groups, whole body PS, PB and net protein balance responses were comparable between the four protein drinks, despite higher postprandial plasma LEU concentrations for the LEU supplemented drinks (P <0.05), and higher insulin concentrations for the CHO supplemented drinks as compared to the protein only drink (P <0.05).Conclusions: Adding CHO and/or LEU to a serving of high-quality protein does not further augment whole body protein anabolism in dyspneic COPD patients at risk for muscle loss or healthy older adults. Trial registry: ClinicalTrials.gov; No. NCT01734473; URL: www.clinicaltrials.gov. (C) 2018 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.
KW - COPD
KW - Leucine
KW - Carbohydrate
KW - Coingestion
KW - Anabolic response
KW - OBSTRUCTIVE PULMONARY-DISEASE
KW - AMINO-ACID-METABOLISM
KW - SKELETAL-MUSCLE
KW - WHEY-PROTEIN
KW - INSULIN
KW - SUPPLEMENTATION
KW - COINGESTION
KW - TURNOVER
KW - ALANINE
KW - CASEIN
U2 - 10.1016/j.clnu.2018.08.006
DO - 10.1016/j.clnu.2018.08.006
M3 - Article
C2 - 30150004
SN - 0261-5614
VL - 38
SP - 1684
EP - 1691
JO - Clinical Nutrition
JF - Clinical Nutrition
IS - 4
ER -