Validating IAAO for Muscle Outcomes
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Protein + Stable Isotope Tracer Beverage.
- Who it may be relevant to
- Registry conditions: Protein Metabolism. Basic parameters: 18 years — 35 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Canada
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
Unsure about the terms? Read our patient guide →
Official title
Validating the Indicator Amino Acid Oxidation Technique for Muscle Outcomes
Overview
Consuming dietary protein stimulates whole-body and muscle protein synthesis, the latter of which is typically measured using invasive primed constant infusions of stable isotopes with concurrent muscle biopsies. Alternative non-invasive methodologies have been developed (namely the indicator amino acid oxidation (IAAO) technique) to estimate the impact of protein ingestion on whole-body protein synthesis as a proxy for determining dietary protein requirements. Given that the IAAO technique is based on principles of protein metabolism which occur in the liver, it is unclear how representative the IAAO outcomes of whole-body protein synthesis is to skeletal muscle protein synthesis. Validation of the IAAO technique against gold-standard, biopsy-derived measures of muscle metabolism (i.e., muscle protein synthesis) would assist in mitigating the invasiveness of muscle physiology and nutrition research.
Interventions
- Dietary supplement Protein + Stable Isotope Tracer Beverage
Participants will consume 12 half-hourly (6 hours) isoenergetic, isonitrogenous beverages containing 0.9g/kg fat-free mass/day protein. Drinks will be enriched with stable isotopes \[2H5\]Phenylalanine and \[1-13C\]Phenylalanine, which will respectively allow for determination of muscle protein synthesis and whole-body protein synthesis over the subsequent 6 hours of feeding
Primary outcome measures
- Phenylalanine excretion (umol/kg/h) [Time frame: 6.5 hours]
- Phenylalanine oxidation (umol/kg/h) [Time frame: 6.5 hours]
- Myofibrillar protein synthesis (%/hr) [Time frame: 6.5 hours]
- Sarcoplasmic protein synthesis (%/hr) [Time frame: 6.5 hours]
Eligibility criteria
Inclusion criteria
- Participants will be aged 18-35 years old
- Participants will have a BMI within the normal range (i.e., 18.5-24.9) and waist-to-hip circumference ratio of <0.95 for males and <0.8 for circumference for females to ensure homogeneity of the sample population
- Participants are willing to abide by the compliance rules of this study (e.g., abstain from extraneous physical activity 48h prior to session 4
- Self-reported regular menstrual cycle (25-35d) within the last 3 months (female participants)
- Physical activity score of ≥24 units as measured by the Godin leisure time exercise questionnaire
Exclusion criteria
- Inability to adhere to any of the compliance rules judged by principal investigator
- Self-reported regular tobacco or illicit drug use (e.g., growth hormone or testosterone)
- Current use of hormonal contraceptives
- Individuals with a history of allergy to local anesthetics (e.g., lidocaine)
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: Yes
Study design
- Allocation
- N/A
- Model
- Single group
- Masking
- Open label
- Primary purpose
- Basic science
Study locations
Canada · 1 center
- Kinesiology & Physical Education — Toronto
Identifiers
NCT: NCT07317921 · VIM