Clinical trial NCT00557388: Dietary Strategies to Promote Muscle Protein Anabolism in the Elderly
Official title: Dietary Strategies to Promote Muscle Protein Anabolism in the Elderly
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Sarcopenia
Keywords: muscle loss
aging
protein
amino acids
exercise
protein synthesis
Lead sponsor: Maastricht University Medical Center
Sponsor class: OTHER
Collaborators: name: National Nutrition and Food Technology Institute
First posted: 2007-11-14
Enrollment: 120
Sex: MALE
Minimum age (years): 18
Maximum age (years): 85
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: Aging is associated with the loss of lean muscle mass, termed sarcopenia. Food intake and in particular the ingestion of protein or amino acids has been shown to be a powerful stimulus to promote net muscle protein anabolism. However this anabolic response following a meal-like protein bolus seems to be blunted in the elderly as compared to young adults.

The first aim of this proposal is to investigate the post-prandial muscle protein synthesis rates in young and elderly men in response to a meal-like protein bolus after a period of rest or physical activity (study A). The rest trial (REST) will act as a proof-of-principle study to examine the blunted protein synthetic response in the elderly, and as a control trial in comparison with the exercise trial (EXC) to establish the surplus value of physical activity prior to protein intake on muscle protein synthesis.

The second aim of this proposal is to determine the surplus value of an increased quantity of the ingested protein bolus (study B). Large amounts of protein (40 and 60 g) will be compared to a meal-like amount of protein (20 g) as a means to maximize plasma amino acid availability and/or to stimulate muscle protein anabolism.

The third aim of this proposal is to study the differences in quality of the ingested protein bolus (study C). Instead of significantly increasing the quantity of the protein bolus, we will also apply a more practical approach to augment skeletal muscle protein synthesis rates; modifying the digestibility or amino acid composition of a meal-like protein bolus.


Eligibility criteria: Inclusion Criteria:

* In study A, non-obese male subjects (BMI \<27) between the age of 18-30 yrs and 70-85 yrs will be selected.
* In studies B and C, non-obese male subjects (BMI \<27) between the age of 70-85 yrs will be selected.

Exclusion Criteria:

* Type II diabetes or other known diseases
* Use of medication
* Female
* Other ages or BMI than indicated above
* Participation in any regular exercise program.

Primary outcomes:
measure: All interventions will affect muscle protein synthesis. With the application of amino acid tracer methodology we are able to determine muscle protein synthesis.
timeFrame: 6 hours
Secondary outcomes:
measure: Differences in rate of uptake/absorption from the intestine.
timeFrame: 6 hours
Other outcomes:
Locations:
city: Maastricht
country: Netherlands
facility: University of Maastricht
state: Limburg
Study officials:
affiliation: Maastricht University
name: Luc van Loon, Phd
role: PRINCIPAL_INVESTIGATOR
References:
citation: Gorissen SHM, Trommelen J, Kouw IWK, Holwerda AM, Pennings B, Groen BBL, Wall BT, Churchward-Venne TA, Horstman AMH, Koopman R, Burd NA, Fuchs CJ, Dirks ML, Res PT, Senden JMG, Steijns JMJM, de Groot LCPGM, Verdijk LB, van Loon LJC. Protein Type, Protein Dose, and Age Modulate Dietary Protein Digestion and Phenylalanine Absorption Kinetics and Plasma Phenylalanine Availability in Humans. J Nutr. 2020 Aug 1;150(8):2041-2050. doi: 10.1093/jn/nxaa024.
citation: Pennings B, Groen B, de Lange A, Gijsen AP, Zorenc AH, Senden JM, van Loon LJ. Amino acid absorption and subsequent muscle protein accretion following graded intakes of whey protein in elderly men. Am J Physiol Endocrinol Metab. 2012 Apr 15;302(8):E992-9. doi: 10.1152/ajpendo.00517.2011. Epub 2012 Feb 14.
citation: Pennings B, Boirie Y, Senden JM, Gijsen AP, Kuipers H, van Loon LJ. Whey protein stimulates postprandial muscle protein accretion more effectively than do casein and casein hydrolysate in older men. Am J Clin Nutr. 2011 May;93(5):997-1005. doi: 10.3945/ajcn.110.008102. Epub 2011 Mar 2.
citation: Pennings B, Koopman R, Beelen M, Senden JM, Saris WH, van Loon LJ. Exercising before protein intake allows for greater use of dietary protein-derived amino acids for de novo muscle protein synthesis in both young and elderly men. Am J Clin Nutr. 2011 Feb;93(2):322-31. doi: 10.3945/ajcn.2010.29649. Epub 2010 Nov 17.