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 September 20, 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 September 20, 2014).

Share This



More Health & Medicine News

Saturday, September 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Could Grief Affect The Immune Systems Of Senior Citizens?

Could Grief Affect The Immune Systems Of Senior Citizens?

Newsy (Sep. 19, 2014) — The study found elderly people are much more likely to become susceptible to infection than younger adults going though a similar situation. Video provided by Newsy
Powered by NewsLook.com
Jury Delivers Verdict in Salmonella Trial

Jury Delivers Verdict in Salmonella Trial

AP (Sep. 19, 2014) — A federal jury has convicted three people in connection with an outbreak of salmonella poisoning five years ago that sickened hundreds of people and was linked to a number of deaths. (Sept. 19) Video provided by AP
Powered by NewsLook.com
How The 'Angelina Jolie Effect' Increased Cancer Screenings

How The 'Angelina Jolie Effect' Increased Cancer Screenings

Newsy (Sep. 19, 2014) — Angelina's Jolie's decision to undergo a preventative mastectomy in 2013 inspired many women to seek early screenings for the disease. Video provided by Newsy
Powered by NewsLook.com
The Cost of Ebola

The Cost of Ebola

Reuters - Business Video Online (Sep. 18, 2014) — As Sierra Leone prepares for a three-day "lockdown" in its latest bid to stem the spread of Ebola, Ciara Lee looks at the financial implications of fighting the largest ever outbreak of the disease. Video provided by Reuters
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