Fate of Nutrient-Derived Amino Acids: Influence of Habituated Levels of Daily Dietary Protein Intake on Protein Utilization
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Bispebjerg Hospital
- Enrollment
- 12
- Locations
- 2
- Primary Endpoint
- Abundance of milk protein-bound amino acid labels in blood protein.
Study Overview
Brief Summary
12 elderly (65-70 years of age) male subjects will be included and complete a double blinded cross-over study. They will be habituated for 21 days to either low or high protein intake (below 0.8 g/kg or above 1.5 g/kg, respectively). Following a 45 day washout period they will switch to the alternate group. At the end of each habituation period, the investigators will measure the appearance of labelled amino acids from milk proteins.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Crossover
- Primary Purpose
- Basic Science
- Masking
- Triple (Participant, Investigator, Outcomes Assessor)
Eligibility Criteria
- Ages
- 65 Years to 70 Years (Older Adult)
- Sex
- Male
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Males age 65-70
- •Independently dwelling
- •Without any major health issues (blood pressure, cholesterol and lipid profile will be measured and evaluated by a physician)
- •Non-diabetic
- •No organ disease
- •No back pain
- •Not regularly take any prescription drugs or dietary supplements, which can influence muscle protein synthesis
- •Alcohol intake below 21 units pr. week
- •No known arthrosclerosis
Exclusion Criteria
- Not provided
Arms & Interventions
Meal serving at high dietary protein
Test the handling of meal-served protein when habituated to high dietary protein at an amount above 1.5 g protein/kg/day
Intervention: Meal serving at high dietary protein (Dietary Supplement)
Meal serving at high dietary protein
Test the handling of meal-served protein when habituated to high dietary protein at an amount above 1.5 g protein/kg/day
Intervention: Meal serving (Dietary Supplement)
Meal serving at low dietary protein
Test the handling of meal-served protein when habituated to high dietary protein at an amount below 0.8 g protein/kg/day
Intervention: Meal serving at low dietary protein (Dietary Supplement)
Meal serving at low dietary protein
Test the handling of meal-served protein when habituated to high dietary protein at an amount below 0.8 g protein/kg/day
Intervention: Meal serving (Dietary Supplement)
Outcomes
Primary Outcomes
Abundance of milk protein-bound amino acid labels in blood protein.
Time Frame: Baseline to 240 min postprandial
Related to the trials conducted after 21 days of habituation to either high or low protein in the diet: After intake of milk proteins at time 0 (zero) the quantity of intrinsic labels D5-phe from whey and 15N-phe from casein will be measured in liver-synthesized blood protein at 240 min.
Secondary Outcomes
- Leg phenylalanine rate of disappearance and appearance, net balance.(Baseline to 240 min postprandial)
- Whole body phenylalanine rate of disappearance and appearance, net balance.(Baseline to 240 min postprandial)
- The myofibrillar protein fractional synthesis rate(Baseline to 240 min postprandial)
- Urea production.(Baseline to 240 min postprandial)
- Fecal microbiota composition(Change from pre-intervention to 21 days and 22 days (21 intervention days habituation and the standardized trial meal on day 21))
- Abundance of milk protein-bound amino acid labels in myofibrillar protein.(Baseline to 240 min postprandial)
- Nitrogen and creatinine excreted in urine(21 days post intervention, 240 min postprandial and 24 hours post the day 21 trial day)
- Adaptation of expression of proteins involved in muscle protein turnover(After 21 days of habituation to either a high or a low dietary protein intake.)
- First pass splanchnic extraction of dietary protein-derived labeled phenylalanine.(Baseline to 240 min postprandial)
- Response of expression of proteins involved in muscle protein turnover(Baseline, 60 min and 240 min postprandial)
Investigators
Grith Højfeldt
MSc. Human Biology - PhD student
Bispebjerg Hospital