Simulated Jetlag for Circadian Rhythm

Overseen By Kenneth Wright, PhD

Age: < 65

Sex: Any

Trial Phase: Academic

Sponsor: University of Colorado, Boulder

Disqualifiers: Medical, psychiatric, sleep disorders

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 6

Duration: 7.7 days per condition

14 Participants Needed

Trial Summary

What is the purpose of this trial?

The purpose of this project is to improve our understanding of peripheral circadian rhythms in humans. Circadian clocks are present in most tissues of the body with importance for optimal physiological function, health, and behavior. This project will utilize simulated jetlag protocols to systematically test novel hypotheses about the regulation of peripheral circadian rhythms in humans. Specifically, we will examine how changes in the time of when we are exposed to light and the timing of when we eat impacts proteins in the blood and saliva that represent rhythms from clocks in the brain (e.g., rhythms of the hormones melatonin and cortisol coordinated by the brain) and rhythms from clocks in body tissues (e.g., proteins made by immune and bone cells, and cells in the stomach and liver). We also aim to discover new blood-based biomarkers of peripheral rhythms in humans. We anticipate our findings will be the first step in developing novel circadian based treatments for aligning peripheral clocks under conditions such as jetlag, and for developing novel circadian biomarkers that will advance our scientific understanding of circadian rhythms.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. However, since the trial excludes participants with any medical, psychiatric, or sleep disorders, it might imply that those on medication for such conditions are not eligible.

What data supports the effectiveness of the simulated jetlag protocol treatment for circadian rhythm disruption?

Research suggests that scheduled exposure to bright light can help adjust the body's internal clock to new time zones, potentially reducing jet lag symptoms. Additionally, using melatonin, a natural hormone that regulates sleep, may speed up the body's adaptation to new time zones. ^{1 2 3 4 5}

Is the Simulated Jetlag Protocol safe for humans?

The safety of the Simulated Jetlag Protocol, which involves exposure to bright light to adjust circadian rhythms, has been studied in the context of jet lag. While some studies suggest it can help with circadian adjustment, the results are mixed, and more research is needed to confirm its safety and effectiveness for the general population. ^{1 5 6 7 8}

How does the Simulated Jetlag Protocol treatment differ from other treatments for circadian rhythm disruption?

The Simulated Jetlag Protocol is unique because it involves deliberately altering the sleep-wake cycle to mimic the effects of jet lag, allowing researchers to study and potentially develop strategies to manage circadian rhythm disruptions. Unlike other treatments that focus on post-travel adjustments, this protocol simulates the condition in a controlled environment, providing insights into the reentrainment process. ^{3 4 5 7 9}

Eligibility Criteria

This trial is for individuals interested in participating in a study about body clocks and how they are affected by changes similar to jetlag. The details on who can join are not provided, but typically participants need to be healthy with no major medical conditions that could affect their circadian rhythm.

Inclusion Criteria

Altitude history: Currently residing at Denver altitude or higher

Healthy

I am between 17 and 35 years old.

Exclusion Criteria

I have a health condition that affects my mind, body, or sleep.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

2 visits (in-person)

Pre-Study Preparation

Participants maintain a regular sleep-wake schedule and wear monitoring devices

2 weeks

2 visits (in-person)

Treatment

Participants undergo two experimental conditions: bright light exposure and earlier timed meals, each for 3 days, under a simulated jetlag protocol

7.7 days per condition

2 visits (in-person, 7.7 days each)

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

Treatment Details

Interventions

• Simulated jetlag protocol

Trial Overview The study is testing how simulated jetlag affects proteins in blood and saliva that indicate the timing of our internal body clocks. It aims to understand how light exposure and meal times influence these biological rhythms, potentially leading to new treatments for real-life jetlag.

Participant Groups

Group I: Meal timing Experimental Treatment 1 Intervention

Three days of meals, bedtimes and wake times scheduled to occur 5h earlier.

Group II: Bright light Experimental Treatment 1 Intervention

Three days of exposure to bright light of \~3,000 lux, which is less than one-third the brightness of a sunrise or sunset (timed to start earlier by 1h each day) with scheduled bed and wake times timed 5h earlier.

Who Is Running the Clinical Trial?

University of Colorado, Boulder

Lead Sponsor

Trials

128

Recruited

29,600+

University of Colorado, Denver

Collaborator

Trials

1,842

Recruited

3,028,000+

Findings from Research

Scheduled exposure to bright light can potentially help alleviate jet lag symptoms by speeding up the body's adjustment to new time zones, but laboratory studies have shown mixed results.

Field studies have shown promise, but their small sample sizes raise questions about how well these findings apply to the general population, highlighting the need for more research on optimal light exposure timing and individual differences.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Light treatment for sleep disorders: consensus report. VII. Jet lag. Boulos, Z., Campbell, SS., Lewy, AJ., et al.[2017]

Bright light and melatonin can be effectively used to help people adapt their circadian rhythms when dealing with night shift work or rapid travel across time zones, as shown in various studies.

By implementing a preflight plan to shift circadian rhythms before travel, jet lag can potentially be completely prevented, highlighting the importance of timing these interventions for optimal effectiveness.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

How to trick mother nature into letting you fly around or stay up all night. Revell, VL., Eastman, CI.[2018]

The MidnightSun program helps travelers manage jet-lag by calculating optimal light exposure times based on their flight itineraries and geographical locations, potentially aiding in the adjustment of circadian rhythms.

By using a database of over 3000 airports and a user-defined phase response curve for light, the program can recommend specific light exposure strategies to minimize the negative effects of jet-lag.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

MidnightSun: software for determining light exposure and phase-shifting schedules during global travel. Houpt, TA., Boulos, Z., Moore-Ede, MC.[2019]

In a study involving an 85-year-old woman, simulated jet-lag showed that her circadian rhythm was less disrupted in terms of amplitude and sleep efficiency when experiencing a phase delay compared to a phase advance.

The woman's circadian rhythm timing adjusted more quickly during the phase advance condition, suggesting that older adults may respond differently to changes in their sleep-wake cycles depending on the direction of the shift.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Inducing jet lag in an older person: directional asymmetry. Monk, TH., Buysse, DJ., Reynolds, CF., et al.[2019]

For short trips (1-2 days), it's best to use strategies like naps and caffeine instead of trying to adapt your internal clock, as immediate adaptation is not feasible.

For longer stays (more than 4-5 days), using light exposure and melatonin can help speed up adjustment to new time zones, but individual differences in adaptation can complicate treatment timing.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Managing jet lag: Some of the problems and possible new solutions. Arendt, J.[2013]

Chronobiotic drugs, particularly melatoninergic medications, show promise in helping people adapt to new time zones and mitigate jet lag symptoms, but larger real-life trials are needed to confirm their efficacy.

While no treatment can instantly adjust the body's internal clock to a new time zone, these drugs can help speed up the adaptation process, highlighting the importance of considering both light exposure and pharmacological interventions in managing jet lag.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Approaches to the Pharmacological Management of Jet Lag. Arendt, J.[2019]

A study involving 28 healthy young subjects found that pre-flight light exposure can effectively phase advance circadian rhythms, with continuous bright light leading to an average advance of 2.1 hours, which can help reduce jet lag after eastward travel.

Both continuous and intermittent bright light treatments significantly outperformed dim light in advancing circadian rhythms, with minimal side effects reported, suggesting that these light strategies could be practical for travelers to mitigate jet lag.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Preflight adjustment to eastward travel: 3 days of advancing sleep with and without morning bright light. Burgess, HJ., Crowley, SJ., Gazda, CJ., et al.[2018]

Bright light exposure has the potential to help resynchronize the circadian system after abrupt time-zone changes, which is important for alleviating jet lag.

However, laboratory studies have not consistently shown that bright light effectively reduces jet lag symptoms, and there are not enough field studies to draw definitive conclusions about its benefits.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Bright light: a countermeasure for jet lag? Samel, A., Wegmann, HM.[2019]

The study uses mathematical models to analyze how quickly people can adjust their internal body clocks (circadian rhythms) after traveling across time zones, revealing that reentrainment times vary based on the direction of travel and the time of year.

It was found that jet lag can occur not only from east-west travel but also from north-south travel due to changes in daylength, suggesting that travelers should consider these factors to minimize jet lag symptoms.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Reentrainment of the circadian pacemaker during jet lag: East-west asymmetry and the effects of north-south travel. Diekman, CO., Bose, A.[2019]

References

1. United States pubmed.ncbi.nlm.nih.gov

Light treatment for sleep disorders: consensus report. VII. Jet lag. [2017]

2. United States pubmed.ncbi.nlm.nih.gov

How to trick mother nature into letting you fly around or stay up all night. [2018]

3. United States pubmed.ncbi.nlm.nih.gov

MidnightSun: software for determining light exposure and phase-shifting schedules during global travel. [2019]

4. England pubmed.ncbi.nlm.nih.gov

Inducing jet lag in an older person: directional asymmetry. [2019]

5. England pubmed.ncbi.nlm.nih.gov

Managing jet lag: Some of the problems and possible new solutions. [2013]

6. New Zealand pubmed.ncbi.nlm.nih.gov

Approaches to the Pharmacological Management of Jet Lag. [2019]

7. United States pubmed.ncbi.nlm.nih.gov

Preflight adjustment to eastward travel: 3 days of advancing sleep with and without morning bright light. [2018]

8. England pubmed.ncbi.nlm.nih.gov

Bright light: a countermeasure for jet lag? [2019]

9. England pubmed.ncbi.nlm.nih.gov

Reentrainment of the circadian pacemaker during jet lag: East-west asymmetry and the effects of north-south travel. [2019]