Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

'Remote control' for cholesterol regulation discovered in brain

07.06.2010
Circulation of cholesterol is regulated in the brain by the hunger-signaling hormone ghrelin, researchers say. The finding points to a new potential target for the pharmacologic control of cholesterol levels.

The animal study, led by Matthias Tschöp, MD, professor in the University of Cincinnati (UC) endocrinology division, appears online ahead of print Sunday, June 6, 2010, in Nature Neuroscience.

"We have long thought that cholesterol is exclusively regulated through dietary absorption or synthesis and secretion by the liver," says Tschöp. "Our study shows for the first time that cholesterol is also under direct 'remote control' by specific neurocircuitry in the central nervous system."

The hormone ghrelin inhibits the melanocortin 4 receptor (MC4R) in the hypothalamus and is important for the regulation of food intake and energy expenditure. Tschöp and his team found that increased levels of ghrelin in mice caused the animals to develop increased levels of blood-circulating cholesterol. This, the authors say, is due to a reduction in the uptake of cholesterol by the liver.

The research team next tested the effects of genetically deleting or chemically blocking MC4R in the central nervous system. This test also yielded increased levels of cholesterol, suggesting that MC4R was the central element of the "remote control."

"We were stunned to see that by switching MC4R off in the brain, we could even make injected cholesterol remain in the blood much longer," says Tschöp, a researcher at UC's Metabolic Diseases Institute.

Cholesterol is a type of naturally occurring fat needed by the body, but too much cholesterol can lead to atherosclerosis, a buildup of plaque in the arteries. There are two types of cholesterol in humans―HDL (high-density lipoprotein) and LDL (low-density lipoprotein). LDL is considered the "bad" kind of cholesterol responsible for plaque buildup. HDL is the "good" kind that, in high levels, can prevent atherosclerosis.

Atherosclerosis can lead to heart attack. The American Heart Association estimates that a heart attack occurs every 34 seconds in the United States.

Due to the differences in the make-up of mice and human cholesterol, Tschöp and his team say more work is needed before their studies could be directly applied to humans, but they say their finding adds to a growing body of evidence for the central nervous system's direct control over essential metabolic processes.

This study was supported by a grant from the National Institutes of Health's National Institute of Diabetes and Digestive and Kidney Diseases.

Co-authors include Stephen Benoit, Joshua Bashford, William Davidson, Norm Granholm, Erin Grant, Susanna Hofmann, David Hui, Ruben Nogueiras, Diego Perez-Tilve, Paul Pfluger, Hilary Wilson-Perez and Stephen Woods, all from the University of Cincinnati; Myrtha Arnold from the Institute of Animal Science in Schwerzenbach, Switzerland; Andrew Butler and James Trevaskis from Pennington Biomedical Research Center in Louisiana; James Patterson and Mark Sleeman from Regeneron Pharmaceuticals; and Richard DiMarchi from Indiana University.

UC's Metabolic Diseases Institute, named in 2009, is located on UC's Reading Campus, formerly the Genome Research Institute, and is home to a team of researchers who focus on the genetic, molecular and cellular mechanisms of metabolic disorders, cancer and cardiovascular disease.

Dama Kimmon | EurekAlert!
Further information:
http://www.uc.edu

More articles from Health and Medicine:

nachricht Cystic fibrosis alters the structure of mucus in airways
28.06.2017 | University of Iowa Health Care

nachricht Mice provide insight into genetics of autism spectrum disorders
28.06.2017 | University of California - Davis

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Supersensitive through quantum entanglement

28.06.2017 | Physics and Astronomy

X-ray photoelectron spectroscopy under real ambient pressure conditions

28.06.2017 | Physics and Astronomy

Mice provide insight into genetics of autism spectrum disorders

28.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>