Molecular Mechanisms Underpinning Sarcopenic Obesity

The coexistence of obesity and sarcopenia results in sarcopenic obesity, a high-risk geriatric condition associated with metabolic perturbations and several co-morbidities. Despite the rising numbers of older adults diagnosed with sarcopenic obesity, few studies have characterized this condition on the muscle cell and systemic level. This study sought to comprehensively assess the influence of sarcopenic obesity on muscle and blood-related parameters and compare it to non-sarocopenic obese and non-sarcopenic lean older adults.

Study Overview

• Status: Recruiting
• Conditions: Obesity; Sarcopenia; Aging; Sarcopenic Obesity
• Intervention / Treatment: Dietary supplement: Essential amino acids (EAA)

• Study Type: Observational
• Enrollment (Estimated): 60

Contacts and Locations

• Study Contact: Name: William Apró, PhD; Phone Number: +46 08-120 538 67; Email: william.apro@gih.se

Study Locations

• Sweden
  • Stockholm, Sweden, 11433
    • Recruiting
    • The Swedish School of Sport and Health Sciences
    • Contact: Oscar Horwath, MSc; Email: oscar.horwath@gih.se

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: N/A

• Sampling Method: Non-Probability Sample

Study Population

The elderly participants will be community-dwelling living in the greater Stockholm metropolitan area. Participants will be recruited through local senior clubs, online communities, advertisement and word of mouth.

The young participants will be living in the greater Stockholm metropolitan area. Participants will be recruited through university forums, online communities, advertisement and word of mouth.

Description

Inclusion Criteria:

• Body fat % in accordance with previously defined criteria
• Free of smoking (since 10 years)
• Able to walk without assistance
• Able to perform bilateral leg extension exercise

Exclusion Criteria:

• History of or present disease of myocardial, vascular, endocrine, hepatic, renal, pulmonary or neuromuscular origin
• Uncontrolled hypo/hypertension
• Use of anticoagulants (Warfarin, Trombyl)
• Use of metformin or other anti-diabetic medications
• Poor appetite and unexplained weight loss (4,5 kg) over the past 6 months
• Active malignancy
• Present infection
• Dementia or delirium
• Other conditions that may interfere with the study protocol in the opinion of the PI

Study Plan

How is the study designed?

Number of groups / cohorts

4

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Sarcopenic obesity; Age: 70-80 years Men, ALM/W < 25.7 %, body fat % > 35 Women, ALM/W < 19.7 %, body fat % > 40	Dietary supplement: Essential amino acids (EAA); intake of 240 mg EAA per kg lean body mass after a resistance exercise session
Non-sarcopenic obese; Age: 70-80 years Men, ALM/W > 25.7 %, body fat % > 35 Women, ALM/W > 19.7 %, body fat % > 40	Dietary supplement: Essential amino acids (EAA); intake of 240 mg EAA per kg lean body mass after a resistance exercise session
Non-sarcopenic lean; Age: 70-80 years Men, ALM > 7.0 kg/m2, body fat % < 25 Women, ALM > 5.5 kg/m2, body fat % < 32	Dietary supplement: Essential amino acids (EAA); intake of 240 mg EAA per kg lean body mass after a resistance exercise session
Young lean; Age: 18-40 years Men, ALM > 7.0 kg/m2, body fat % < 25 Women, ALM > 5.5 kg/m2, body fat % < 32	Dietary supplement: Essential amino acids (EAA); intake of 240 mg EAA per kg lean body mass after a resistance exercise session

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Fiber type-specific cell signalling	This measure will be investigated during an experimental trial in which the participants are subjected to an acute bout of resistance exercise followed by the ingestion of essential amino acids (240 mg/kg lean mass). During this 3 hour time period, the participants will donate two muscle biopsies, one before exercise and the second one 1 hour after exercise. Cell signalling networks related to muscle mass regulation will be examined in these biopsy samples. The signal will be measured using Western blotting and the signal obtained is expressed in relation to baseline (adjusted volume intensity).	1 hour after ingestion of essential amino acids and resistance exercise

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Whole body glucose tolerance	Oral glucose tolerance test in which the participants will ingest a standardized glucose drink and blood glucose levels will be monitored throughout a period of 2 hours. Unit of measurement is mmol/L glucose.	2 hours
Accelerometer-assessed physical activity levels	Hip-worn accelerometer data (Actigraph GT3X) collected over 7 consecutive days. Unit of measurement is steps per day.	1 week
Isometric and isokinetic leg muscle strength	Muscle performance will be evaluated at a single timepoint during the study using IsoMed2000 dynamometer. Participants will perform a maximal isometric contraction at 60 degrees of knee flexion. Unit of measurement is Newton meter (N-m).	1 hour
Skeletal muscle fiber characteristics	Fiber type-specific area measured using immunofluorescence microscope in muscle biopsies collected at baseline (prior to ingestion of essential amino acids and resistance exercise). Unit of measurement is square micrometers (µm^2).	1 hour prior to ingestion of essential amino acids and resistance exercise
Whole body muscle volume	Indices of muscle volume and fat infiltration obtained with magnetic resonance imaging (MRI). Unit of measurement is cubic centrimeters (cm^3).	1 hour

Collaborators and Investigators

• Sponsor: The Swedish School of Sport and Health Sciences
• Investigators: Principal Investigator: William Apró, PhD, The Swedish School of Sport and Health Sciences and Karolinska Institute, Stockholm Sweden

Study record dates

Study Major Dates

• Study Start (Actual): January 28, 2020
• Primary Completion (Estimated): December 15, 2025
• Study Completion (Estimated): December 30, 2025

Study Registration Dates

• First Submitted: October 10, 2023
• First Submitted That Met QC Criteria: November 1, 2023
• First Posted (Actual): November 7, 2023

Study Record Updates

• Last Update Posted (Estimated): December 11, 2023
• Last Update Submitted That Met QC Criteria: December 4, 2023
• Last Verified: December 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nervous System Diseases; Neurologic Manifestations; Overnutrition; Nutrition Disorders; Overweight; Body Weight; Neuromuscular Manifestations; Pathological Conditions, Anatomical; Muscular Atrophy; Atrophy; Obesity; Sarcopenia
• Other Study ID Numbers: 2019-04016

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No