Restoring Molecular Circadian Rhythm

January 21, 2026 updated by: University of Pennsylvania

Exploratory Pilot Study to Discover Genes That Restore the Molecular Circadian Rhythm

The goal is to address the mechanisms that account for alteration of circadian rhythms with age. As the blood of aged individuals can produce this alteration, the investigators propose to use such blood samples to "age" circadian rhythms in cultured cells. The investigators will verify aged blood-dependent alteration of rhythms and then conduct molecular screens to reverse this decline. If the investigators identify specific genes that can restore molecular circadian rhythm in vitro, the investigators will explore these in animal models (Drosophila, mouse).

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Suspended

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Observational

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
40

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Pennsylvania
      • Philadelphia, Pennsylvania, United States, 19104
        • University of Pennsylvania School of Medicine

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

20 years to 85 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Sampling Method

Probability Sample

Study Population

Apparent healthy volunteers

Description

Inclusion Criteria:

  • General good health with the following conditions permissible

    • cardiovascular risk prevention, intake of low dose aspirin,
    • hypertension, intake of beta-blockers, ACE inhibitors, diuretics, calcium channel blockers
    • hypercholesterinemia, intake of statins
  • Cases: 70-85 years of age
  • Controls: 20-35 years of age
  • Patients must be able to read and understand English
  • Participants must sign the informed consent form
  • Participants must have a wrist-actigraphy-based average TST (total sleep time) ≥ 6 hours per night (measured over 7 consecutive days) occurring between 22:00 - 08:00

Exclusion Criteria:

  • Known history of severe psychiatric or cognitive conditions, for example mania, schizophrenia, or mental retardation
  • Shift work, defined as recurring work between 22:00-05:00
  • History of clinically significant obstructive sleep apnea
  • Transmeridian travel across ≥2 time zones in the two weeks prior to the blood draws and one week after,
  • > 2 drinks of alcohol per day
  • Use of illicit drugs

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Observational Models: Case-Control
  • Time Perspectives: Cross-Sectional

Cohorts and Interventions

Group / Cohort

Group / Cohort

A group or subgroup of participants in an observational study that is assessed for biomedical or health outcomes.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Young
Observational study without intervention
Other: Observational study without intervention
Observational study without intervention
Elderly
Observational study without intervention
Other: Observational study without intervention
Observational study without intervention

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Delta of period length measured in hh:mm between in vitro cycling fibroblasts incubated with serum collected from cases (elderly adults) versus controls (young adults)
Time Frame: Time point 14:00 Hours
To determine if serum collected from young versus old healthy study participants have a differential effect on the expression of circadian rhythms in an in vitro culture of a fibroblast cell line
Time point 14:00 Hours
Delta of phase measured in HH:mm between in vitro cycling fibroblasts incubated with serum collected from cases (elderly adults) versus controls (young adults)
Time Frame: Time point 14:00 Hours
The primary endpoint will be the difference in phase angle in vitro between cycling fibroblasts and incubated with serum collected from cases (old adults) versus controls (young adults)
Time point 14:00 Hours

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Chronotype
Time Frame: 4 weeks
Assessed per survey; chronotypes per Munich Chronotype questionnaire are extreme early type, moderate early type, slight early type, normal type, slight late type, moderate late type, extreme late type
4 weeks
Acrophase
Time Frame: 7 days
Clock hour of peak physical activity averaged from 7 or more days of actigraphy
7 days
Physical activity
Time Frame: 7 days
Vector magnitude of physical activity averaged from 7 or more days of actigraphy
7 days
Sleep quantity
Time Frame: 7 or more days
Hours of sleep averaged from 7 or more days of actigraphy
7 or more days
Sleep quality: actigraphy
Time Frame: 7 days
Sleep fragmentation averaged from 7 or more days of actigraphy
7 days
Ambient light exposure
Time Frame: 7 days
Ambient light exposure averaged from 7 or more days of actigraphy
7 days
Heart rate variability
Time Frame: 24 hours
Heart rate variability (RR intervals) averaged from 24 hours of BioPatch
24 hours
Saliva cortisol
Time Frame: 24 hours
Difference in concentrations of cortisol measured in saliva between morning versus evening
24 hours

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Pennsylvania

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Carsten Skarke, MD, University of Pennsylvania

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
August 19, 2019

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
January 1, 2028

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
November 1, 2028

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
August 19, 2019

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 9, 2019

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
September 11, 2019

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
January 23, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 21, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
January 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 832866

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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