But researchers from Brown University, Rhode Island Hospital and the University of Texas Southwestern Medical Center have discovered that Sirt1 in the brain has its own potential health benefit: It may keep people thinner.
They determined that inhibiting the activity of Sirt1 in the brain's hypothalamic region appears to help control food intake — a finding that potentially lays the groundwork for new treatments for obesity. Details will be published online Dec. 15, 2009, at PLoS ONE.
The discovery is the culmination of the first in-depth study of the metabolic role of Sirt1 in the brain. It suggests that Sirt1 behaves differently in the brain than in organs such as the liver and pancreas, where the enzyme has been more commonly studied.
Sirt1 research so far has posited that fasting activates Sirt1 and thereby helps extend life. Drug companies and scientists have also thrown their support behind resveratrol, a compound found in red wine, thought to be beneficial to the body because it may activate Sirt1. The new Brown research challenges at least some of the preexisting findings, because scientists found that inhibiting the activity of Sirt1 in the brains of rats, rather than stimulating it, appeared to reduce appetite, leading to a smaller weight gain compared to untreated animals. They believe a similar mechanism exists in human brains.
"It's still controversial whether calorie restriction or resveratrol are Sirt1 stimulators," said Eduardo Nillni, the study's lead author. Nillni is professor of medicine (research) at the Warren Alpert Medical School of Brown University and a member of the Department of Molecular Biology, Cell Biology and Biochemistry. At Rhode Island Hospital, Nillni is senior investigator in the Division of Endocrinology. Other authors include researchers from Brown and the University of Texas Southwestern Medical Center.
Nillni's team did find that fasting helped increase Sirt1 production and activity in the brain, consistent with the view that reducing food intake stimulates Sirt1 elsewhere in the body. But they generated clear data showing that pharmacologically or genetically inhibiting Sirt1 activity in the brain led to the animals eating less food and gaining fewer pounds compared to their untreated counterparts.
The study also indentified specific brain receptors or sites where Sirt1 induced food intake — the melanocortin receptors.
Nillni said that more work should be done to investigate whether or how the brain pathways involving Sirt1 and food intake are affected in obese animals.
The National Institutes of Health funded the study.
Editors: Brown University has a fiber link television studio available for domestic and international live and taped interviews, and maintains an ISDN line for radio interviews. For more information, call (401) 863-2476.
Mark Hollmer | EurekAlert!
Antibiotic effective against drug-resistant bacteria in pediatric skin infections
17.02.2017 | University of California - San Diego
Tiny magnetic implant offers new drug delivery method
14.02.2017 | University of British Columbia
Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...
The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.
The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...
Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...
Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".
Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
17.02.2017 | Medical Engineering
17.02.2017 | Medical Engineering
17.02.2017 | Health and Medicine