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 Plasmonic biosensors enable development of new easy-to-use health tests
14.12.2017 | Aalto University

nachricht ASU scientists develop new, rapid pipeline for antimicrobials
14.12.2017 | Arizona State University

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: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Plasmonic biosensors enable development of new easy-to-use health tests

14.12.2017 | Health and Medicine

New type of smart windows use liquid to switch from clear to reflective

14.12.2017 | Physics and Astronomy

BigH1 -- The key histone for male fertility

14.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>