21 avril, 2005 14:30
Internal Clock Tied to Metabolic Problems in Mice
Thu Apr 21, 2005 6:42 PM ET
NEW YORK (Reuters Health) - The internal clock or circadian rhythm that controls body functions may influence a person's risk of obesity and other metabolic problems, findings from an animal study suggest.
In mice, a gene called Clock is a key regulator of the circadian rhythm, which, in humans, repeats about every 24 hours. In the new study, Dr. Fred W. Turek, from Northwestern University in Evanston, Illinois, and colleagues evaluated mice that have mutations in the Clock gene.
Compared with normal mice, these mutant animals had several feeding and metabolic disturbances, according to the report in the journal Science. The mice displayed excessive feeding and became obese. In addition, they had high cholesterol and sugar levels in the blood, as well as fat accumulation in the liver.
Further analysis showed that certain brain proteins involved in energy balance were reduced in the mutant mice, the investigators point out.
The current findings emphasize how "critical" normal circadian rhythm is "for the health and well being of the organism," the authors conclude.
SOURCE: Science, April 21, 2005.
