Immune Cells During Disuse and Recovery

Official title

Muscle Immune Cells During Disuse and Recovery in Aging and Metabolic Disease

Overview

This is an interventional study enrolling healthy individuals aged 18-35 and 60-85 to understand the recovery of muscle health following a period of inactivity. The enrollment goal is 45 participants. The study will occur over the course of 1-2 months where participants will undergo testing before and after a 2-week limb immobilization period.

Detailed description

Visit 1 (Pre-testing)- After signing a consent form, participants will undergo a blood screening and an oral glucose tolerance test. After the visit, participants will be provided with a step activity monitor to track their level of activity. A dietary assessment will also be determined.

Visit 2- At a later time, the participant will return to the research center for a biopsy, blood draw, body composition scan, MRI and muscle strength testing.

2-week leg immobilization period- After visit 2 , the participant will return home and undergo a 14-day leg immobilization period using the equipment and instructions provided at visit 2.

Visit 3- During the limb immobilization period, participant will return to the research center for a single blood draw.

Visit 4- At the end of the 2-week limb immobilization period, the participant will return to the research center to undergo another biopsy, blood draw, body composition scan, MRI and muscle strength testing.

Visit 5- 2 days after the 2-week limb immobilization period, the participant will return for a biopsy and blood draw.

Visit 6- 7 days after the 2-week limb immobilization period, the participant will be asked to return for a final biopsy, blood draw, body composition scan, MRI and muscle strength testing.

Interventions

• Other Limb immobilization
  Participants will undergo a 2-week period of leg immobilization

Primary outcome measures

• Thigh Muscle Volume [Time frame: baseline and after 2 weeks of leg immobilization]
• Leg Muscle Strength [Time frame: baseline and after 2 weeks of leg immobilization]

Eligibility criteria

Inclusion criteria

• Age between 18-35 and 60-85 yrs
• Ability to sign informed consent
• Free-living, prior to admission

Exclusion criteria

• History of cardiovascular disease (e.g., CHF, CAD, right-to-left shunt)
• History of endocrine or metabolic disease such as hypo/hyperthyroidism and diabetes
• History of kidney disease or failure
• Vascular disease
• Risk of DVT including family history of thrombophilia, DVT, pulmonary emboli, myeloproliferative diseases including polycythemia (Hb>18 g/dL) or thrombocytosis (platelets>400x103/mL), and connective tissue diseases (positive lupus anticoagulant), hyperhomocystinemia, deficiencies of factor V Leiden, proteins S and C, and antithrombine III
• Use of anticoagulant therapy (e.g., Coumadin, heparin)
• Elevated systolic pressure >150 or a diastolic blood pressure > 100
• Implanted electronic devices (e.g., pacemakers, electronic infusion pumps, stimulators)
• Cancer or history of successfully treated cancer (less than 1 year) other than basal cell carcinoma
• Currently on a weight-loss diet
• Chronic systemic corticosteroid use (≥ 2 weeks) within 4 weeks of enrollment and for study duration (intra-articular/topical/inhaled therapeutic or physiologic doses of corticosteroids are permitted)
• Androgens or growth hormone within 6 months of enrollment and for study duration (topical physiologic androgen replacement is permitted)
• History of stroke with motor disability
• A recent history (<12 months) of GI bleed
• History of liver disease
• History of respiratory disease (acute upper respiratory infection, history of chronic lung disease)
• Pregnancy as determined by a pregnancy test
• Any staff members who report directly to an investigator or who report to someone who reports directly to an investigator.
• Any other condition or event considered exclusionary by the PI and faculty physician

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

United States · 1 center

• The University of Utah — Salt Lake City

Publications

• Skiles CM, Fennel ZJ, Bourrant PE, Yee EM, Castro RJ, Zabriskie HA, Itinose M, Supiano MA, O'Connell RM, Drummond MJ. Robust immune cell infiltration and macrophage senescence occur within a week of recovery after limb immobilization in older adult skeletal muscle. J Physiol. 2026 Apr;604(8):3379-3395. doi: 10.1113/JP290346. Epub 2026 Mar 27. PMID 41891949

Identifiers

NCT: NCT04416191 · 130232

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗