Influence of Leucine Enriched Amino Acids on Myofibrillar and Collagen Protein Synthesis

Not Applicable

Active, not recruiting

• Conditions: Interventional
• Interventions: Dietary Supplement: Leucine enriched amino acids; Dietary Supplement: Carbohydrate Placebo

• Registration Number: NCT05554653
• Lead Sponsor: Daniel Moore

Brief Summary

The primary objective will be to determine the effect of leucine-enriched essential amino acids (LEAA) compared to carbohydrate placebo on dietary incorporation of \[D5\] Phenylalanine \& \[D5\] Glycine into the three skeletal muscle protein pools (myofibrillar, sarcoplasmic and collagen), both following resistance exercise and at rest, with the two tracers provided as a 'intrinsically labeled' bolus. Other outcomes will relate to molecular regulation of protein synthesis.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2022-09-19
• Study First Submitted QC: 2022-09-22
• Study First Posted: 2022-09-26
• Study Start: 2022-10-01
• Primary Completion: 2023-10-03
• Status Verified: 2023-11
• Last Update Submitted: 2023-11-08
• Last Update Posted: 2023-11-13
• Study Completion: 2024-08

Recruitment & Eligibility

• Status: ACTIVE_NOT_RECRUITING
• Sex: All
• Target Recruitment: 8

Inclusion Criteria

• Healthy, male and female, recreationally-active participants.
• Healthy will be defined as screened by the PAR-Q+ (The Physical Activity Readiness Questionnaire for everyone; Appendix B).
• Self-reported not having engaged in resistance exercise and/or lower body plyometrics for at least 3 months prior to the study.
• Participants will be aged 18-35 years old.
• Participants are willing to abide by the compliance rules of this study.
• Self-reported regular menstrual cycle (25-35d) within the last 3 months (female participants).

Exclusion Criteria

• Inability to adhere to any of the compliance rules judged by principle investigator or medical doctor.
• Self-reported regular tobacco use.
• Self-reported illicit drug use (e.g. growth hormone, testosterone, etc.).
• Individuals who have participated in studies within the past year involving any of the stable isotopes in the study.
• Use of birth control and discontinued use within the last 3 months (female participants).

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Leucine enriched essential amino acids	Leucine enriched amino acids	Leucine enriched essential amino acids (4g total, of which 1.6g are leucine). 20g carbohydrate, 2g of protein free drink powder, and 5g of Splenda to mask taste.
Carbohdyrate Placebo	Carbohydrate Placebo	Iso-caloric placebo (4g maltodextrin to replace LEAA). 20g carbohydrate, 2g of protein free drink powder, and 5g of Splenda to mask taste.

Primary Outcome Measures

Name	Time	Method
Myofibrillar Protein synthesis	4 hours	Rate of incorporation of orally ingested amino acid tracers (D5 Phe and D5 Gly) into myofibrillar proteins isolated from skeletal muscle biopsies 4h following drink (LEAA or PLA) consumption and resistance exercise or at rest. Enrichment will be quantified via tandem LC-MS/MS to derive a rate of incorporation over the 4h period.

Secondary Outcome Measures

Name	Time	Method
Collagen protein synthesis	4 hours	Rate of incorporation of orally ingested amino acid tracers (D5 Phe and D5 Gly) into collagen (i.e., non-soluble) proteins isolated from skeletal muscle biopsies 4h following drink consumption (LEAA or PLA) and resistance exercise or at rest. Enrichment will be quantified via tandem LC-MS/MS.
Sarcoplasmic protein synthesis	4 hours	Rate of incorporation of orally ingested amino acid tracers (D5 Phe and D5 Gly) into sarcoplasmic (i.e., soluble) proteins isolated from skeletal muscle biopsies 4h following drink consumption (LEAA or PLA) and resistance exercise or at rest. Enrichment will be quantified via tandem LC-MS/MS.
Protein localization via immunofluorescence	4 hours	Antibody-determined Phosphorylated RPS6 (S240/244) and mTOR protein localization in human muscle cross sections and longitudinal sections as examined via immunofluorescence. Muscle sections (both longitudinal and cross-sections) will be derived from snap-frozen muscle biopsies performed 4h following drink consumption (LEAA or PLA) with or without resistance exercise (unilateral). Localization will be performed as done by Hodson et al., (2022; AJP Cell). Particularly, the localization of these targets relative to the cell periphery and z-discs (longitudinal sections only) will be analyzed via colocalization analysis.

Trial Locations

Locations (1)

Goldring Centre for High Performance Sport at the University of Toronto; 🇨🇦 Toronto, Ontario, Canada