Featured Research

from universities, journals, and other organizations

Disruption Of Circadian Rhythms Affects Both Brain And Body, Mouse Study Finds

Date:
October 28, 2009
Source:
Society for Neuroscience
Summary:
A new study has found that chronic disruption of one of the most basic circadian (daily) rhythms -- the day/night cycle -- leads to weight gain, impulsivity, slower thinking, and other physiological and behavioral changes in mice, similar to those observed in people who experience shift work or jet lag.

Night and day. Experiments with mice, such as one in which scientists gauge the rodents' willingness to venture from a dark compartment to a bright one, show that disrupting circadian rhythms has a pronounced impact on behavior and physiology.
Credit: Image courtesy of Rockefeller University

Anyone who has pulled an all-nighter or flown across an ocean knows you can’t mess up your sleep schedule without unpleasant consequences. New research in mice now shows that throwing off natural circadian rhythms over the long term can seriously disturb the body and brain, causing weight gain and impulsive behavior. It seems even to make mice dumber, or at least slower at solving new mazes.

A new study has found that chronic disruption of one of the most basic circadian (daily) rhythms -- the day/night cycle -- leads to weight gain, impulsivity, slower thinking, and other physiological and behavioral changes in mice, similar to those observed in people who experience shift work or jet lag.

The research, presented at Neuroscience 2009, the annual meeting of the Society for Neuroscience is helping scientists better understand the neurobiological mechanisms behind circadian disruptions.

"Our findings have implications for humans," said lead author Ilia Karatsoreos, PhD, of Rockefeller University. "In our modern industrialized society, the disruption of our individual circadian rhythms has become commonplace, from shift work and jet lag to the constant presence of electric lighting. These disruptions are not only a nuisance, they can also lead to serious health and safety problems," he said.

Karatsoreos and his colleagues housed the animals in a day/night cycle of 20 hours (10 hours of light and 10 hours of dark), rather than the roughly 24-hour cycle to which the animals' internal brain and body clocks are normally set. After six to eight weeks, the mice exhibited numerous physiological changes not seen in a control group.

While not any more active than the control mice, the disrupted mice were impulsive, a behavior measured in part by how long they wait to emerge into the light from a dark compartment in a cage. They were slower to figure out changes made to a water maze they had mastered, suggesting reduced mental flexibility. Physically, their body temperature cycles were disorganized when compared to their peers and the levels of hormones related to metabolism, such as leptin, which regulates appetite, and insulin, were elevated. Consequently the mice gained weight even though they were fed the same diet as the controls.

The researchers also found that the brains of the disrupted mice had shrunken and less complex neurons in the medial prefrontal cortex, an area important to the so-called executive function, which regulates mental flexibility among other things. “Those changes may help explain some of the behavioral effects of circadian disruptions,” Karatsoreos says.

Research was supported by Canadian Institutes of Health Research, the National Institute of Mental Health, and Sepracor.


Story Source:

The above story is based on materials provided by Society for Neuroscience. Note: Materials may be edited for content and length.


Cite This Page:

Society for Neuroscience. "Disruption Of Circadian Rhythms Affects Both Brain And Body, Mouse Study Finds." ScienceDaily. ScienceDaily, 28 October 2009. <www.sciencedaily.com/releases/2009/10/091026225744.htm>.
Society for Neuroscience. (2009, October 28). Disruption Of Circadian Rhythms Affects Both Brain And Body, Mouse Study Finds. ScienceDaily. Retrieved August 27, 2014 from www.sciencedaily.com/releases/2009/10/091026225744.htm
Society for Neuroscience. "Disruption Of Circadian Rhythms Affects Both Brain And Body, Mouse Study Finds." ScienceDaily. www.sciencedaily.com/releases/2009/10/091026225744.htm (accessed August 27, 2014).

Share This




More Health & Medicine News

Wednesday, August 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

WHO Calls for Ban on E-Cigarette Sales to Minors

WHO Calls for Ban on E-Cigarette Sales to Minors

AFP (Aug. 26, 2014) — The World Health Organization called Tuesday on governments should ban the sale of e-cigarettes to minors, warning that they pose a "serious threat" to foetuses and young people. Duration: 01:44 Video provided by AFP
Powered by NewsLook.com
Have You Ever Been 'Sleep Drunk?' 1 in 7 Has

Have You Ever Been 'Sleep Drunk?' 1 in 7 Has

Newsy (Aug. 26, 2014) — A study published in the journal "Neurology" interviewed more than 19,000 people and found 15 percent suffer from being "sleep drunk." Video provided by Newsy
Powered by NewsLook.com
Does Medical Marijuana Reduce Painkiller Overdose Deaths?

Does Medical Marijuana Reduce Painkiller Overdose Deaths?

Newsy (Aug. 26, 2014) — A new study found fewer deaths from prescription drug overdoses in states that have legalized medical marijuana. But experts disagree on the results. Video provided by Newsy
Powered by NewsLook.com
Official: British Ebola Sufferer Receiving Experimental Drug

Official: British Ebola Sufferer Receiving Experimental Drug

AFP (Aug. 26, 2014) — A British nurse infected with Ebola while working in Sierra Leone is being given the same experimental drug used on two US missionaries who have recovered for the disease, doctors in London say. Duration: 00:44 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



    Save/Print:
    Share:  

    Free Subscriptions


    Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

    Get Social & Mobile


    Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

    Have Feedback?


    Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
    Mobile iPhone Android Web
    Follow Facebook Twitter Google+
    Subscribe RSS Feeds Email Newsletters
    Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins