Friday, June 9, 2023
SCIENMAG: Latest Science and Health News
No Result
View All Result
  • Login
  • HOME PAGE
  • BIOLOGY
  • CHEMISTRY AND PHYSICS
  • MEDICINE
    • Cancer
    • Infectious Emerging Diseases
  • SPACE
  • TECHNOLOGY
  • CONTACT US
  • HOME PAGE
  • BIOLOGY
  • CHEMISTRY AND PHYSICS
  • MEDICINE
    • Cancer
    • Infectious Emerging Diseases
  • SPACE
  • TECHNOLOGY
  • CONTACT US
No Result
View All Result
Scienmag - Latest science news from science magazine
No Result
View All Result
Home SCIENCE NEWS Social & Behavioral Science

Muscles have circadian clocks that control exercise response

October 20, 2016
in Social & Behavioral Science
0
Share on FacebookShare on Twitter
  • Humans may be able to respond better to exercise during the daytime.
  • Oxygen and the internal clock "do a dance together" in muscle cells to make energy
  • Insights could lead to optimizing muscle function

CHICAGO — Northwestern Medicine scientists have discovered circadian clocks in muscle tissue that control the muscle's metabolic response and energy efficiency depending on the time of day.

The finding in mice sheds light on the time-of-day differences in muscle's ability to adapt to exercise and use oxygen for energy. Muscle cells are more efficient during an organism's normal waking hours, the study found.

All cells in the body, including those in muscle, contain a clock that regulates how cells adapt to changes in the environment and activity across the 24-hour day.

"Oxygen and the internal clock are doing a dance together inside muscle cells to produce energy, and the time of day determines how well that dance is synchronized," said senior author Dr. Joseph Bass. "The capacity for a cell to perform its most important functions, to contract, will vary according to the time of day."

More research is needed before the finding can be translated into workout advice.

"We're not saying we can tell athletes when they should work out," Bass said, "but in the future, perhaps, you may be able to take advantage of these insights to optimize muscle function."

Bass is the Northwestern Medicine chief of endocrinology, metabolism and molecular medicine, and director of the Center for Diabetes and Metabolism at Northwestern University Feinberg School of Medicine. He also is a member of the Robert H. Lurie Comprehensive Cancer Center of Northwestern University.

Clara Bien Peek, the first author and a research assistant professor, spearheaded the work on muscle and timing.

The paper will be published Oct. 20 in the journal Cell Metabolism.

The research has implications beyond muscle cells because oxygen response is important in all cells. In particular, the deprivation of oxygen is a key factor in heart attacks and in cancer, in which the depletion of oxygen curiously enables cancer cells to grow.

Mice adapted to exercise better at night; humans might during day

In the research, scientists performed studies in mice, which were exercised on a treadmill at different times of day, as well as in isolated muscle fibers in which the circadian clock was genetically mutated.

The scientists analyzed mouse muscle tissues and muscle fibers for expression of genes that are important for exercise. In this way, they determined the impact of deregulation of the circadian clock on muscle fibers in terms of how muscle processes fuel, like sugar and fat, when oxygen levels are low.

"When we manipulated the clock genetically, we noticed there were profound abnormalities in the muscle," Bass said. "That set us on a course to understand how the inner muscle clock is important in regulating how well the muscle cell can mobilize energy."

When mice, which are nocturnal, are exercised during the night, their muscles are better at turning on genes to help them adapt to exercise, scientists found. Since these genes also exist in humans, this suggests humans may also be able to respond better to exercise during the daytime.

The muscle clocks control the metabolic response by interacting with proteins called HIFs that change metabolism when oxygen concentrations get too low in order to allow muscle cells to continue to make energy.

Normally when we rest or do low-level exercise, our muscles consume oxygen to make energy. When we start to sprint or exercise strenuously, we consume oxygen faster and quickly run out. That's when the dip in oxygen triggers HIFs and signals muscles to switch to sugar for energy–which in turn increases lactic acid.

Turning off the muscle clock prevented the normal capacity of exercise to induce sugar consumption and generation of lactic acid. These findings suggest that better exercise capacity may be tied to specific times of day.

Future may bring new ways to manipulate oxygen in muscles

"In the future, we may discover new ways to manipulate the oxygen response of the cell by resetting the clock," said Bass, who also holds the Charles F. Kettering Professorship of Medicine at Feinberg. He noted drugs are available that can manipulate the internal clock in cells.

"If we can optimize muscle function, " he said, "it's also a critical step in understanding how to impact glucose metabolism in diabetes."

Diabetes is characterized by a failure of muscle to consume glucose, which in turn controls blood sugar levels. Strengthening the muscle clock may provide a new way to eliminate excess glucose and treat diabetes.

The scientists tested their theories about the internal clock in muscle cells because those cells are particularly dependent on oxygen for contraction and metabolism.

"We wanted to determine the rules that interconnect clocks with the physiological use of oxygen," Bass said. "We believe that studying muscle can provide us with the rules of how clocks govern response to oxygen, and we would like to test these principles in a variety of conditions."

###

Other Northwestern authors include Kathryn Moynihan Ramsey, Dr. Jonathan Cedernaes, Dr. Akihiko Taguchi, Daniel C. Levine, Yumiko Kobayashi,

Stacy J. Tsai, Nicolle A. Bonar, Maureen R. McNulty,

The paper is titled "Circadian Clock Interaction with HIF1α Mediates Oxygenic Metabolism and Anaerobic Glycolysis in Skeletal Muscle."

The study was supported by National Institutes of Health grants R01DK090625, R01DK100814 and K01DK105137-02 from the National Institute of Diabetes and Digestive and Kidney Diseases and grant P01AG011412 from the National Institute on Aging. Lynn Sage Cancer Research Foundation and others also supported the study.

Media Contact

Marla Paul
[email protected]
@northwesternu

http://www.northwestern.edu

Share25Tweet16Share4ShareSendShare
  • Schrödinger’s cat code

    Schrödinger’s cat makes better qubits

    65 shares
    Share 26 Tweet 16
  • The problems with coal ash start smaller than anyone thought

    66 shares
    Share 26 Tweet 17
  • ‘Revolutionary’ research discovers new cause of cancer coming from inside us

    65 shares
    Share 26 Tweet 16
  • Birmingham spinout to develop 20-minute test following surge in sexually transmitted infections

    64 shares
    Share 26 Tweet 16
  • Taurine may be a key to longer and healthier life

    64 shares
    Share 26 Tweet 16
  • Nearly 70% of private label avocado oil rancid or mixed with other oils

    67 shares
    Share 27 Tweet 17
ADVERTISEMENT

About us

We bring you the latest science news from best research centers and universities around the world. Check our website.

Latest NEWS

UTHSC researchers’ work on human pangenome aids understanding of common chromosomal abnormality

Null results research now published by major behavioral medicine journal

Multiple sclerosis more prevalent in Black Americans than previously thought

Subscribe to Blog via Email

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

Join 206 other subscribers

© 2023 Scienmag- Science Magazine: Latest Science News.

No Result
View All Result
  • HOME PAGE
  • BIOLOGY
  • CHEMISTRY AND PHYSICS
  • MEDICINE
    • Cancer
    • Infectious Emerging Diseases
  • SPACE
  • TECHNOLOGY
  • CONTACT US

© 2023 Scienmag- Science Magazine: Latest Science News.

Welcome Back!

Login to your account below

Forgotten Password?

Retrieve your password

Please enter your username or email address to reset your password.

Log In