Development of Oral Amino Acid Tracers to Study Protein Turnover in Humans

NCT04887727 | Completed

• 1 other identifier: Connaught
• Study Type: interventional
• Target: 22
• Locations: 1 country
• Sites: 1

Brief Summary

Previous studies have used a combination of oral L-\[1-13C\]leucine and intravenous labeled L-\[5,5,5-2H3\]leucine to assess the acute postprandial changes in whole-body protein turnover (12, 19). Intravenous and dietary-labeled amino acid tracers have also been used in tandem to assess rates of myofibrillar protein synthesis in response to bolus protein ingestion and resistance exercise (46). By validating whole-body net balance to myofibrillar protein synthesis, our proposed multi-tracer approach will develop minimally invasive models to study protein turnover in a variety of populations in which traditional infusions and/or repeated blood samples are not possible (i.e. pediatric, free-living populations).

Conditions

Healthy Adult Males

Outcome Measures

Primary Outcomes (1)

• Myofibrillar protein synthesis rates

  Myofibrillar protein synthesis rates assessed by oral and intravenous tracers during Fast, Fed, and Ex-Fed

  5 hours

Secondary Outcomes (4)

• Whole-body protein turnover

  5 hours

• Amino acid oxidation and net protein balance

  5 hours

• Muscle anabolic signalling

  2 and 5 hours

• Amino acid transporter expression

  2 and 5 hours

Study Arms (2)

Healthy, recreationally-active adult males - Muscle Trial

EXPERIMENTAL

Subjects receive 0.25g/kg crystalline amino acids modelled after egg protein, enriched with L-\[1-13C\]leucine and L-ring-\[2H5\]phenylalanine with a primed-constant infusion of L-\[555-2H3\]leucine to assess myofibrillar protein synthesis rates

Dietary Supplement: Crystalline amino acids to assess myofibrillar protein synthesis rates

Healthy, recreationally-active adult males - Whole Body Trial

EXPERIMENTAL

Subjects receive 0.25g/kg crystalline amino acids modelled after egg protein, enriched with L-\[1-13C\]leucine with a primed-constant infusion of L-\[555-2H3\]leucine to whole-body protein turnover, amino acid oxidation, and net protein balance

Dietary Supplement: Crystalline amino acids to assess whole-body protein turnover, amino acid oxidation, and net protein balance

Interventions

Crystalline amino acids to assess myofibrillar protein synthesis rates DIETARY_SUPPLEMENT

Amino acid dose = 0.25g/kg bodyweight

Healthy, recreationally-active adult males - Muscle Trial

Crystalline amino acids to assess whole-body protein turnover, amino acid oxidation, and net protein balance DIETARY_SUPPLEMENT

Amino acid dose = 0.25g/kg bodyweight

Healthy, recreationally-active adult males - Whole Body Trial

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Male
• Currently performing structured physical activity 2-5 days per week

You may not qualify if:

• Unable to safely perform exercise as per PARQ+ guidelines
• Currently using tobacco products
• Currently using or have history of anabolic steroid use
• Diagnosed with medical condition including type 2 diabetes, cancer, heart disease
• Unable to abstain from supplement use (HMB, branched chain amino acids, phosphatidic acid) for at least three weeks prior to trial
• currently using medications known to affect protein metabolism e.g. corticosteroids, NSAID, prescription-strength acne medication
• allergic to local anesthetics
• female: Hormonal fluctuations associated with the menstrual cycle have been reported to alter protein metabolism during exercise and may influence indices of the post-exercise myofibrillar protein synthetic response. Accordingly, the study will include males to ensure a stable hormonal environment and to increase the homogeneity of the physiological response.

Sponsors & Collaborators

• University of Toronto: lead

Study Sites (1)

Goldring Centre for High Performance Sport at the University of Toronto

Toronto, Ontario, M5S2C9, Canada

Location

Related Publications (1)

• Mazzulla M, Hodson N, West DWD, Kumbhare DA, Moore DR. A non-invasive 13CO2 breath test detects differences in anabolic sensitivity with feeding and heavy resistance exercise in healthy young males: a randomized control trial. Appl Physiol Nutr Metab. 2022 Aug 1;47(8):860-870. doi: 10.1139/apnm-2021-0808. Epub 2022 May 24.

  PMID: 35609328 DERIVED

Study Officials

• Daniel R Moore, PhD

  University of Toronto

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Model Details: Three groups: Fast, Fed, Ex-Fed Two trials per group

Study Record Dates

• First Submitted: May 5, 2021
• First Posted: May 14, 2021
• Study Start: February 25, 2019
• Primary Completion: August 31, 2019
• Study Completion: August 31, 2019
• Last Updated: May 14, 2021

Record last verified: 2021-05

Data Sharing

• IPD Sharing: Will not share

Locations

CA (1)