Mitochondrial Function in Peripheral Blood Mononuclear Cells, Muscle, and Skin of Long COVID Patients

NCT07134673 | Recruiting

• 2 other identifiers: EC-2025-071G075423N
• Study Type: observational
• Target: 54
• Locations: 1 country
• Sites: 1

Brief Summary

Mitochondria are structures inside cells that are responsible for producing energy from nutrients through a series of steps, using oxygen. To have an idea of how well the mitochondria can produce energy, we can measure how much oxygen they use. The goal of this study is to:

• Complete surveys,
• Wear an activity tracker (7 days),
• Undergo several non-invasive tests, and
• Donate a blood sample The study will take place in UZ Brussel hospital and will take 2 study visits, approximately 7 days apart.

Conditions

Long COVID; Post-COVID-19 Condition

Keywords

mitochondrial dysfunction

Outcome Measures

Primary Outcomes (4)

• Basal Oxygen Consumption rate (pmol O2/min)

  Seahorse XF Substrate Oxidation Stress test analysis of the peripheral blood mononuclear cells (PBMCs)

  Blood sample is taken during the second study visit (approximately 7 days after the first study visit) and the PBMCs are cryopreserved until analysis (after all participants have been recruited, estimated to be within 1 year of the start of the study)

• Tissue Saturation Index (TSI)

  Near-infrared spectroscopy

  Second study visit (approximately 7 days after the first study visit)

• Mitochondrial oxygen tension (mitoPO2) (mmHg/s)

  Cellular Oxygen Metabolism monitoring

  Second study visit (approximately 7 days after the first study visit)

• Mitochondrial oxygen consumption (mitoVO2)

  Cellular Oxygen Metabolism monitoring

  Second study visit (minimally 7 days after the first study visit)

Secondary Outcomes (16)

• Proportion of participants meeting the criteria for PEM

  Second study visit (minimally 7 days after the first study visit)

• General fatigue

  Second study visit (approximately 7 days after the first study visit)

• Physical fatigue

  Second study visit (approximately 7 days after the first study visit)

• Mental fatigue

  Second study visit (approximately 7 days after the first study visit)

• Reduced activities

  Second study visit (approximately 7 days after the first study visit)

Other Outcomes (1)

• Weight (kg)

  Second study visit (approximately 7 days after the first study visit)

Study Arms (2)

Individuals with long COVID

History of a confirmed or documented SARS-CoV-2 infection and long COVID according to the World Health Organisation's clinical case definition

Convalescent individuals

History of a confirmed or documented SARS-CoV-2 infection, complete recovery after the SARS-CoV-2 infection, no history of long COVID according to the World Health Organisation's clinical case definition

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Study participants will be recruited in the Universitair Ziekenhuis Brussel, from the general population in Belgium through traditional and social media, as well as in the vicinity of the study site through leaflets and posters.

You may qualify if:

• Long COVID diagnosis, based on the WHO definition;
• Presence of long COVID symptoms for a minimum of 6 months.
• History of confirmed or documented SARS-CoV-2 infection.
• Adult (≥18 years of age).
• Post-COVID-19 Functional Status Scale grade 2-4, while they had a grade 0 before the SARS-CoV-2 infection.

You may not qualify if:

• Pre-existing chronic diseases potentially affecting the functional status scale.
• Treatment with metabolism altering drugs.
• \> 10 standard units of alcohol (10 grams of alcohol/glass) per week.
• Unable to understand oral and written instructions in Dutch, French or English.
• Allergies to medical adhesive bandages.
• Porphyria and other skin conditions aggravated by sunlight.
• Convalescent individuals
• History of confirmed or documented SARS-CoV-2 infection.
• Complete recovery after the SARS-CoV-2 infection, no history of long COVID based on the WHO definition;
• Post-COVID-19 Functional Status Scale \[2\] grade 0 both before the infection and currently.
• Adult (≥18 years of age).
• Pre-existing chronic non-communicable diseases (e.g. hypertension, chronic respiratory diseases, diabetes).
• Treatment with metabolism altering drugs.
• \> 10 standard units of alcohol (10 grams of alcohol/glass) per week.
• Unable to understand oral and written instructions in Dutch, French or English.

Sponsors & Collaborators

• Universitair Ziekenhuis Brussel: lead

Study Sites (1)

Laarbeeklaan 101

Jette, Brussels Capital, 1090, Belgium

RECRUITING

Biospecimen

Retention: SAMPLES WITH DNA

Peripheral Blood Mononuclear Cells

MeSH Terms

Conditions

Post-Acute COVID-19 Syndrome; Mitochondrial Diseases

Condition Hierarchy (Ancestors)

COVID-19; Pneumonia, Viral; Pneumonia; Respiratory Tract Infections; Infections; Virus Diseases; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; RNA Virus Infections; Lung Diseases; Respiratory Tract Diseases; Post-Infectious Disorders; Chronic Disease; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Metabolic Diseases; Nutritional and Metabolic Diseases

Study Officials

• Elisabeth De Waele, MD. PhD.

  Vitality Research Group, Metabolism and Nutrition, Vrije Universiteit Brussel (VUB), Clinical Nutrition Department, Universitair Ziekenhuis Brussel (UZ Brussel)

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Berenice G. Jimenez Garcia, Master of Science

CONTACT

+3224749624; berenice.gabriela.jimenez.garcia@vub.be

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Head of the Department of Clinical Nutrition, Co-director of Vitality Research Group

Study Record Dates

• First Submitted: June 25, 2025
• First Posted: August 21, 2025
• Study Start: January 21, 2026
• Primary Completion (Estimated): July 1, 2026
• Study Completion (Estimated): July 1, 2026
• Last Updated: April 22, 2026

Record last verified: 2025-08

Locations

BE (1)