Re-evaluation of the Muscle-full Effect During Continuously Elevated Amino Acid Availability in Healthy Young Males

NCT ID: NCT06721026

Last Updated: 2024-12-13

Basic Information

• Recruitment Status: NOT_YET_RECRUITING
• Clinical Phase: NA
• Total Enrollment: 12 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-03-01
• Study Completion Date: 2026-02-01

Brief Summary

Muscle tissue consists of proteins. These proteins are built up of a collection of smaller building blocks: amino acids. When protein is consumed, it gets digested and absorbed into the blood. The body can use these amino acids, by taking them up from thecirculation. By consuming sufficient protein through our diet, we ensure that the body is provided with enough amino acids to enable muscle protein building. Sufficient muscle protein synthesis is important for maintaining muscle function and strength.

Previous research has shown that when 20 to 25g of protein is eaten, muscle protein synthesis is maximized. It is therefore recommended to eat 20g of protein per meal. However, it is currently unclear what happens to muscle protein synthesis rates if multiple meals are eaten. When multiple meals are consumed, amino acids appear in the circulation for prolonged period of time.

Theoretically, when there are a high amino acid concentrations in the blood, muscle protein synthesis rates will increase. Contrary to this theory, a study more than 20 years ago showed otherwise. It was observed that muscle protein synthesis rates are only elevated for2 hours afterwhich they decrease again. This phenomenon was referred to as the "muscle-full" effect. Because this phenomenon is in contrast with more previous studies, the objective is to replicate that study. This is important so that nutritional advice for healthy, but also clinical populations in the future can be improved.

Conditions

Muscle Protein Synthesis

Keywords

amino acid infusion; tracer methodology; muscle biopsy

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

Continuous amino acid infusion

Tracer infusions combined with infusion of a mixture of amino acids

Group Type: EXPERIMENTAL

Continuous intravenous stable isotope amino acid tracer infusion

Intervention Type: OTHER

During the single 12 h trial day, a primed continuous stable isotope infusion will run in order to assess muscle protein synthesis in the basal (4 h) and post-prandial (8 h) state.

Amino acid infusion

Intervention Type: OTHER

In order to assess muscle protein synthesis rates during continuous elevated plasma amino acid availability, the amino acid infusion solution Vamin®14 EF will be used. Vamin® 14EF contains 85g amino acids per liter and will be administered in the post-prandial period for 8 hours to ensure a constant rate of amino acid infusion over the full assessment period of the primary outcome measure.

Interventions

Continuous intravenous stable isotope amino acid tracer infusion

During the single 12 h trial day, a primed continuous stable isotope infusion will run in order to assess muscle protein synthesis in the basal (4 h) and post-prandial (8 h) state.

Intervention Type: OTHER

Amino acid infusion

In order to assess muscle protein synthesis rates during continuous elevated plasma amino acid availability, the amino acid infusion solution Vamin®14 EF will be used. Vamin® 14EF contains 85g amino acids per liter and will be administered in the post-prandial period for 8 hours to ensure a constant rate of amino acid infusion over the full assessment period of the primary outcome measure.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Male sex
• Aged between 18 - 35 years
• Healthy (assessed based on routine medical questionnaire)
• BMI between 18.5 - 30 kg/m2

Exclusion Criteria

A potential subject who meets any of the following criteria will be excluded from participation in this study:

• Smoking
• Involved in progressive exercise training
• A history of neuromuscular problems
• Use of anticoagulants
• Recent (<12 months) participation in amino acid tracer (L-[ring-13C6] phenylalanineand L-[3,5-2H2]-tyrosine) studies
• Use of medication known to affect (muscle) protein metabolism (e.g. corticosteroids, non-steroidal anti-inflammatory drugs, acne medication)
• Phenylketonuria
• Diagnosed with or history of liver damage
• Diagnosed with or history of severe kidney damage and/or malfunction
• Diagnosed with inability to break down amino acids

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 35 Years
• Eligible Sex: MALE
• Accepts Healthy Volunteers: Yes

Sponsors

Maastricht University Medical Center

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Luc van Loon, PhD

Role: PRINCIPAL_INVESTIGATOR

Maastricht University

Locations

Maastricht University Medical Centre+

Maastricht, Limburg, Netherlands

Countries

Netherlands

Central Contacts

Luc van Loon, PhD

Role: CONTACT

Phone: 0031433881743

Email: l.vanloon@maastrichtuniversity.nl

Facility Contacts

Noortje Boot, MSc

Role: primary

Other Identifiers

METC24-028

Identifier Type: -

Identifier Source: org_study_id