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Preterm BirthNCT06334107

Mitochondrial DNA Signatures of Poor Aerobic Exercise Trainability in Young Adults Born Preterm

A study testing Exercise in people with Preterm Birth, run by Texas Tech University at 1 site in United States.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Sites and contacts
Official record
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Trial summary

Young adults born very preterm (32 weeks gestation or earlier) do not respond well to aerobic exercise training, meeting the recommendations set by the Physical Activity Guidelines for Americans, where they do not increase their fitness level (or cardiorespiratory fitness). Read more about this study

Who is it for?
Ages 18 to 35 yearsHealthy volunteers can take part
Conditions the study is for
Preterm Birth
What is being tested?
Exercise
Could I receive a placebo?
No, everyone receives an active treatment
How many people
60 participants
Where
1 siteUnited States
Study dates
1 May 2024to 31 Dec 2026
Phase
Interventional
Are there results?
Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 35 years
  • All sexes
  • Healthy volunteers accepted
  • Adult

Who may be able to join

  • Preterm born (PTB)young adult group: Participants must be inactive (reported exercise \< 150 mins/week; See IPAQ Attachment), males and females aged 18-35 years born preterm with a gestational age \<37 weeks.
  • Normal term-born (NTB) young adult control group: Participants must be inactive (reported exercise \< 150 mins/week) and will be age- and sex-matched and born at term (37 gestational age).
  • The biological mother of PTB participants: The PTB biological birth mother must be the one who gave birth to the participant and the one from whom the child inherited half of its genetic background (i.e., DNA).
  • PTB and NTB young adults must pass the PAR-Q+ Questionnaire assessment, indicating readiness to begin a moderate-intensity exercise training program. We will follow the American College of Sports Medicine\'s aerobic exercise training program participation guidelines. Subjects who are cleared via the PAR-Q+ assessment will be permitted to participate in the training program.

Who cannot join

  • PTB and NTB young adults only: Having a diagnosed bronchopulmonary hyperplasia, cardiovascular (cardiac or peripheral arterial disease), metabolic (Diabetes Mellitus Type 1 or 2), or renal or liver disease, and signs or symptoms of these conditions, including pain: discomfort in the chest, neck, jaw, arms, or other areas that may result from ischemia; shortness of breath at rest or with mild exertion; dizziness or syncope; orthopnea or paroxysmal nocturnal dyspnea; ankle edema; palpitations or tachycardia; intermittent claudication; known heart murmur; unusual fatigue or shortness of breath with usual activity.

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

Heather L Vellers, Ph.D. contact

8068348554

heather.l.vellers@ttu.edu

Heather L Vellers, Ph.D. contact

9792194343

heather.l.vellers@ttu.edu

United States1 site, 1 recruiting
  • Texas Tech University | Kinesiology and Sport Management Building

    Lubbock, Texas, 79409

    Heather L Vellers, Ph.D., 806-834-8554, heather.l.vellers@ttu.edu

    Heather L Vellers, Ph.D., 9792194343, heather.l.vellers@ttu.edu

    Recruiting

Other trials in United States

About this study

Young adults born very preterm (32 weeks gestation or earlier) do not respond well to aerobic exercise training, meeting the recommendations set by the Physical Activity Guidelines for Americans, where they do not increase their fitness level (or cardiorespiratory fitness). Thus, they do not receive the health benefits of exercise. Achieving physical fitness through aerobic exercise training is the most cost-effective method for preventing and treating many diseases. Young adults born very preterm also have a higher risk of these conditions. Thus, their inability to respond to increase their fitness is a major problem.

One likely explanation for poor exercise trainability and increased heart disease risk in young adults born very preterm is the effect of the early birth on the major energy producers in all our cells: Mitochondria. During late-stage gestation, mitochondria change from relying on sugar as a major fuel source to fat. Unfortunately, individuals born very preterm miss this transition in fuel source reliance, which causes significant stress and damage to mitochondria. Mitochondria are critical for post-natal organ development; thus, it is thought that preterm birth-induced mitochondrial dysfunction is the underlying cause of poor trainability and high disease risk in young adults born very preterm. Indeed, mitochondrial dysfunction is evident in these individuals.

Read more

To date, there is not a way to help young adults born preterm improve their fitness level. One likely target is in the mitochondria: it's DNA. Mitochondrial DNA helps determine how mitochondria function and can be damaged under stress. Our goal in this proposed work is to determine the role of mitochondrial DNA in mitochondrial dysfunction and its link to their poor trainability.

Questions:

  1. Are there mitochondrial DNA markers linked to mitochondrial dysfunction and poor exercise trainability in young adults very born preterm?
  2. Do mitochondrial DNA in young adults born very preterm respond differently to aerobic exercise training than those born at term?

The investigators expect this work will show mitochondrial DNA changes linked to mitochondrial dysfunction and poor trainability, which can be used for future targets to improve health. This work supports AHA mission by helping to identify a marker in individuals born very preterm linked to their higher heart disease risk and death early in life.

Read the detailed description

Young adults born very preterm (VPTB; ≤ 32 weeks gestational age) have an impaired response to aerobic exercise training (AET), often characterized by no change in aerobic capacity (VO2max) following AET. This diminishes the potential of AET to offset their elevated cardiovascular disease risk early in life VPTB\'s poor trainability is linked to their known mitochondrial dysfunction, thought to occur due to blunted mitochondrial maturation with early birth. Currently, no therapeutics are available to improve VO2max trainability for this population.

Data from our lab in humans and mice demonstrate that mitochondrial DNA (mtDNA) variants and other mitochondrial genomic aspects have a role in VO2max trainability. In humans, the investigators found that individuals with the largest increase in VO2max following AET had a higher occurrence of mitochondrial heteroplasmy (a shift in sequence across mtDNA). In contrast, heteroplasmy decreased in those with little-to-no change in VO2max. The reduction in heteroplasmy correlated with higher mtDNA lesions, suggesting exercise was inflicting excessive oxidative stress on mitochondria in these individuals. The investigators also identified 13 mtDNA variants in those with poor trainability, possibly linked to their lowered heteroplasmy response after exercise training. These data indicate that genetic diversity characterized by the response of mtDNA heteroplasmy with AET is an important factor determining the adaptability of VO2max with AET. To date, VPTB mitochondrial genomes have not been characterized. An onset of variants in their mitogenomes due to early birth would be easily identifiable compared to their birth mother, given that mtDNA is maternally inherited. Importantly, these mitogenome variants may inform the effect of AET on heteroplasmy and their low trainability. Thus, there is a critical need to characterize VPTB mitochondrial genome characteristics and how AET influences these dynamics.

Our long-term goal is to improve mitochondrial function and VO2max trainability in VPTB young adults facing disproportionately higher disease risk where exercise is known to be beneficial as a treatment and preventative measure. Accordingly, the overall objectives of this application are to i) characterize VPTB-induced mtDNA changes in sequence, heteroplasmy, and damage, and ii) determine the effect of AET on these mtDNA traits and mitochondrial function in cells known to correlate with heart mitochondrial oxidative capacity: namely peripheral blood mononuclear cells (PBMCs). Our central hypothesis is that VTPB young adults will have unique mtDNA variants/mutations and that AET will significantly decrease PBMC mtDNA heteroplasmy and copies alongside lowered mitochondrial oxidative capacity compared to normal-term birth (NTB) adults. The rationale for this project is that characterizing unique VPTB mtDNA aspects and the heteroplasmy response to AET might reveal an underlying mechanism for their poor trainability that can be targeted for future work. To meet these objectives, the investigators will assess these two specific aims: Aim 1: Assess for informative mtDNA variants in VPTB young adults. The investigators hypothesize there will be de novo mtDNA variants in VPTB offspring compared to their birth mothers.

Aim 2: Determine the effect of AET on mitochondrial oxidative capacity and mtDNA heteroplasmy, copy number, and lesions in isolated PBMCs in VPTB and NTB young adults. The investigators hypothesize VPTB adults will exhibit decreased mtDNA heteroplasmy and increased lesions following AET compared to age-matched NTB adults.

After completing the proposed research, our expected outcome is identifying a unique signature of mtDNA variants and heteroplasmy responses to AET in VPTB adults that will explain their low trainability. These results are expected to have a positive impact for researchers because it will provide a foundation for future research to target mtDNA as a strategy to help VPTB adults reduce their risk for cardiovascular disease and improve their quality of life.

Conditions
Preterm Birth
Being tested
Exercise
Keywords
Preterm birth, Aerobic capacity trainability, mitochondrial DNA, heteroplasmy, mitochondrial oxidative capacity
Medical subject headings
Premature Birth

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • ExerciseBehavioural

    Participants will be asked to follow a moderate-intensity aerobic exercise training program for 4-5 days per week for 40-60 minutes each session.

Study groups in NCT06334107
Study groupRoleWhat they receive
Aerobic Exercise TrainingExperimentalParticipants will be asked to complete a 16-week aerobic exercise training program.
Receives: Behavioral: Exercise
Mitochondrial DNA SequencingNo interventionParticipants will be asked to provide a blood or saliva sample for mitochondrial DNA sequencing analysis to assess for variants unique to individuals born prematurely.

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Mitochondrial DNA heteroplasmy

    The full-length mitochondrial DNA sequence will be analyzed and assessed for heteroplasmic sites in the mitochondrial genome. Briefly, mitochondrial DNA exists in many copies, and heteroplasmy is noted when the amino acid sequence changes from the major read 2% or more across the DNA copies. The change in the mean heteroplasmy frequency and the mean number of sites with heteroplasmy with aerobic exercise training by comparing these changes in young adults born preterm to those born at term.

    Measured: Immediately after aerobic exercise training intervention; change in pre- to post-frequency

  2. Mitochondrial DNA sequence variants

    The full-length mitochondrial DNA sequence will be determined in participants who report being born prematurely, which will be compared to their biological birth mother. In this comparison, we will assess for variants. We deem a site as an 'informative' mitochondrial DNA variant in young adults born prematurely as a change in amino acid sequence from the biological birth mother.

    Measured: Immediately after visit 1

  3. Change in maximal aerobic capacity

    The change in maximal aerobic capacity will be assessed via the modified Balke-graded exercise test before and after the aerobic exercise training program.

    Measured: Immediately after aerobic exercise training intervention; change in pre- to post-frequency

  4. Change in mitochondrial oxidative capacity in peripheral blood mononuclear cells

    Mitochondrial maximal respiration (i.e., oxidative capacity) will be measured in isolated peripheral blood mononuclear cells.

    Measured: Immediately after aerobic exercise training intervention; change in pre- to post-frequency

Secondary outcomes (1)
  1. Daily sleep habits

    Daily sleep data will be collected from the Fitbit Charge via the Fitabase software program during the experimental period. Subjects will be instructed to create a habit of wearing their Fitbit Charge each night of the training period. At the completion of the study, the research team will collect daily sleep data that includes the estimated time spent (i.e., minutes or seconds) in each stage (awake, rapid eye movement, light, and deep).

    Measured: Daily for 16 weeks.

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted27 Mar 2024
  2. Study start1 May 2024
  3. Primary completion1 Dec 2026 (estimated)
  4. Study completion31 Dec 2026 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Basic science
Allocation
Non-randomised
Intervention model
Parallel groups
Masking
Single blind
Who is masked
Participant
Enrolment
60 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT06334107
Sponsor's protocol ID
24AIREA1191995
Status last verified
Dec 2025
First submitted
18 Mar 2024
Last updated
18 Dec 2025
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Questions about this trial

What is this clinical trial studying?

A study testing Exercise in people with Preterm Birth, run by Texas Tech University at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 4 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: looking for participants now, as of the sponsor's last update on 18 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

Contact Heather L Vellers, Ph.D. (8068348554, heather.l.vellers@ttu.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Mitochondrial DNA heteroplasmy (time frame: Immediately after aerobic exercise training intervention; change in pre- to post-frequency). The study lists 4 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Dec 2025.

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