Single Nuclei Sequencing in Human Skeletal Muscle After Unloading

Launched by KAROLINSKA INSTITUTET · Mar 23, 2023

Keywords

ClinConnect Summary

This study looks at how a short period of not using one leg affects the muscles at the cellular level. In a small group of healthy men, participants will undergo a 5-day unilateral lower limb suspension (one leg unloaded while the other bears weight). The leg that is unloaded will wear a shoe with a very thick sole to keep the leg in a nearly straight position and allow only passive movement. The main goal is to see how individual muscle cells in the thigh muscle (vastus lateralis) change when there is no mechanical use. Right after the 5 days, researchers will take tissue samples from both legs to study cell activity at the genetic level. They will also measure muscle size and strength before and after.

About 10 healthy men, ages 18-40, are planned to join. Participants must not have contraindications to MRI or intense resistance exercise, and must not have major health issues or very high baseline physical activity. Before and after the 5-day period, you’ll have MRI scans to check muscle size and tests of knee muscle strength. After unloading, you’ll have small tissue samples taken from both legs. The trial is run by Karolinska Institutet in Sweden and is currently enrolling by invitation; it does not have results yet, and completion is estimated around August 2025.

Gender

MALE

Eligibility criteria

• Inclusion Criteria:
• • Healthy young adult men
• Exclusion Criteria:
• • An age younger than 18 or older than 40 years
• • Contraindications to magnetic resonance imaging (MRI)
• • Contraindications to maximal intensity resistance exercise
• • Contraindications to unloading (i.e., ULLS)
• • Very high physical activity levels (determined using a standard Godin Leisure-Time Exercise Questionnaire (GLTEQ))
• • Hypertension (\>140/90 mm Hg)
• • History of malignancy
• • History of coagulation dysfunction
• • History of musculoskeletal or neurological disorders
• • History of cardiovascular disease
• • History of cerebrovascular disease
• • History of respiratory disease
• • History of gastrointestinal disease
• • History of renal disease
• • History of past or present condition requiring long-term drug prescriptions.