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 Cholesterol-lowering drugs may fight infectious disease
22.08.2017 | Duke University

nachricht Once invincible superbug squashed by 'superteam' of antibiotics
22.08.2017 | University at Buffalo

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: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Cholesterol-lowering drugs may fight infectious disease

22.08.2017 | Health and Medicine

Meter-sized single-crystal graphene growth becomes possible

22.08.2017 | Materials Sciences

Repairing damaged hearts with self-healing heart cells

22.08.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>