Navigation Links
Temperature rhythms keep body clocks in sync, UT Southwestern researchers find

DALLAS Oct. 14, 2010 Researchers at UT Southwestern Medical Center have found that fluctuations in internal body temperature regulate the body's circadian rhythm, the 24-hour cycle that controls metabolism, sleep and other bodily functions.

A light-sensitive portion of the brain called the suprachiasmatic nucleus (SCN) remains the body's "master clock" that coordinates the daily cycle, but it does so indirectly, according to a study published by UT Southwestern researchers in the Oct. 15 issue of Science.

The SCN responds to light entering the eye, and so is sensitive to cycles of day and night. While light may be the trigger, the UT Southwestern researchers determined that the SCN transforms that information into neural signals that set the body's temperature. These cyclic fluctuations in temperature then set the timing of cells, and ultimately tissues and organs, to be active or inactive, the study showed.

Scientists have long known that body temperature fluctuates in warm-blooded animals throughout the day on a 24-hour, or circadian, rhythm, but the new study shows that temperature actually controls body cycles, said Dr. Joseph Takahashi, chairman of neuroscience at UT Southwestern and senior author of the study.

"Small changes in body temperature can send a powerful signal to the clocks in our bodies," said Dr. Takahashi, an investigator with the Howard Hughes Medical Institute. "It takes only a small change in internal body temperature to synchronize cellular 'clocks' throughout the body."

Daily changes in temperature span only a few degrees and stay within normal healthy ranges. This mechanism has nothing to do with fever or environmental temperature, Dr. Takahashi said.

This system might be a modification of an ancient circadian control system that first developed in other organisms, including cold-blooded animals, whose daily biological cycles are affected by external temperature changes, Dr. Takahashi said.

"Circadian rhythms in plants, simple organisms and cold-blooded animals are very sensitive to temperature, so it makes sense that over the course of evolution, this primordial mechanism could have been modified in warm-blooded animals," he said.

In the current study, the researchers focused on cultured mouse cells and tissues, and found that genes related to circadian functions were controlled by temperature fluctuations.

SCN cells were not temperature-sensitive, however. This finding makes sense, Dr. Takahashi said, because if the SCN, as the master control mechanism, responded to temperature cues, a disruptive feedback loop could result, he said.


Contact: Aline McKenzie
UT Southwestern Medical Center

Related medicine news :

1. Researchers find future temperatures could exceed livable limits
2. Temperature-sensing protein linked to skin cancer, hirsutism
3. As Temperatures Rise, So Do Cocaine Deaths
4. As Temperature Plummets, Its Still Safe to Exercise
5. Almac Launches New STEMS System to Transform Temperature Controlled Shipment Monitoring in Clinical Trials
6. UT Southwestern study to determine whether leptin helps type 1 diabetes patients
7. UT Southwestern researchers create experimental vaccine against Alzheimers
8. Blood test could diagnose Alzheimers disease, UT Southwestern researchers find
9. NIH awards $8 million to UT Southwestern to study metabolism, obesity-related inflammation
10. Lung cancer culprit could offer target for therapy, UT Southwestern researchers report
11. UT Southwestern University Hospital -- St. Paul recognized as Primary Stroke Center
Post Your Comments:
(Date:11/25/2015)... ... ... For the first time, Vitalalert is donating half of its earnings to ... between the two groups began in 2014 with Vitalalert pledging a portion of every ... founded in 1954 and is an international Christian-based health organization whose mission is to ...
(Date:11/25/2015)... ... 2015 , ... Dental professionals who would like to become more proficient on ... Dr. Mark Iacobelli’s Advanced Implant Mentoring (AIM) CE course. Courses will be held on ... co-founders of Advanced Implant Mentoring (AIM), Dr. Iacobelli and Dr. D’Orazio are proud to ...
(Date:11/25/2015)... (PRWEB) , ... November 25, 2015 , ... The McHenry ... a recent successful appellate decision obtained by Attorneys Francisco J. Botto and Alex C. ... v. Illinois Workers’ Compensation Comm’n, 2015 IL App (2d) 130884WC. , According to court ...
(Date:11/25/2015)... ... November 25, 2015 , ... SCOTTSDALE, AZ) - Today, ... in both surgical and non-surgical treatments, announced the expansion of his private practice ... Surgery. , Highly trained and nationally recognized for his natural approach, Dr. ...
(Date:11/25/2015)... ... , ... In an ongoing Clinical Study conducted by an independent physician, Andrew ... is evaluating the efficacy of its product and its disinfection protocol. This study is ... May 2014 through October 2015 at a 360-bed, acute-care, academic medical center located in ...
Breaking Medicine News(10 mins):
(Date:11/25/2015)... THOUSAND OAKS, Calif. , Nov. 25, 2015 /PRNewswire/ ... of a Biologics License Application (BLA) with ... Administration (FDA) for ABP 501, a biosimilar candidate to ... the first adalimumab biosimilar application submitted to the FDA ... biosimilar pathway. Sean E. Harper , M.D., ...
(Date:11/25/2015)... , Nov. 25, 2015  Linden Care, LLC, a ... treatment outcomes for patients suffering from chronic pain, said ... a Temporary Restraining Order (TRO) enjoining Express Scripts from ... companies. --> --> ... of its legal options. --> ...
(Date:11/25/2015)... , Nov. 25, 2015 On ... first federal bellwether trial against Wright Medical Technology, ... to their Conserve metal-on-metal hip implant device, awarded ... Following a two week trial and three days ... metal-on-metal hip device was defectively designed and unreasonably ...
Breaking Medicine Technology: