Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Research mice help scientists understand the complexities of cholesterol

17.03.2006


Scientists at Wake Forest University School of Medicine and colleagues have developed new research mice to help them better understand how the body makes and uses "good" cholesterol to protect against heart attacks and strokes. Their latest findings are reported in the April issue of the Journal of Clinical Investigation.



"Being able to develop drugs to raise levels of good cholesterol depends on knowing more about the how and where the particles are formed," said John S. Parks, Ph.D., from Wake Forest University School of Medicine. "These animals provide the first tools to address these questions."

High-density lipoprotein (HDL) cholesterol is called "good" cholesterol because higher levels are associated with lower risk of heart attacks. Physicians and scientists believe that HDL carries cholesterol away from the blood vessels and to the liver, where it is passed from the body. It may also help remove excess cholesterol from plaque in arteries, slowing the buildup that can lead to heart attacks and strokes.


Parks, a professor of pathology in the Section on Lipid Sciences, is part of a multi-center team that has developed three groups of research mice to investigate the complexities of good cholesterol. These specially developed mice have mutations in a gene (ABCA1) involved in HDL production. The scientists are using them to pinpoint where good cholesterol is produced and how it helps fight plaque buildup. In one group of animals, the ABCA1 gene is selectively deleted in the liver – which means their livers cannot produce HDL. It was through studying these mice that the scientists were able to report in 2005 that the liver is likely the body’s main source of good cholesterol – producing 70 to 80 percent.

Now, in the Journal of Clinical Investigation, they report that the intestines are the other source – producing 20 to 30 percent. This finding came from studying mice with the ABCA1 gene deleted in the intestine. Before these findings, scientists had thought that HDL formation occurred throughout the body – rather than coming from specific organs.

Scientists also know that very small amounts of HDL are produced in macrophages, cells in the blood vessel walls that are involved in the formation of plaques. Through studying the third group of mice – which produces no HDL in the vessel walls – the scientists hope to answer a conundrum about this source of good cholesterol. Previous research indicates that while the levels of HDL produced in the vessels are very small, it may play a large role in keeping the vessels healthy.

Knowing exactly what organs produce good cholesterol – and which sources are most important in fighting vessel disease – will allow drug developers to target specific organs to raise HDL levels. Currently, there are few drugs to raise HDL levels, and people who need to raise their HDL levels are advised to get more exercise.

The group will use the mice to evaluate potential drug therapies. Several drugs have been developed that can stimulate the ABCA1 gene to produce good cholesterol, but they aren’t useable in humans because of negative side effects. The scientists hope to learn more about how the drugs work and how they could be improved.

"The animals can help us determine which pathways are affected by drug therapy, which can eventually be translated to human studies," said Parks. "They are a valuable tool in the quest to find a therapy to raise HDL concentrations and retard the development of heart disease."

Parks’s colleagues on the current research are from the University of British Columbia in Vancouver, Canada, University Medical Center Groningen, The Netherlands, Academic Medical Center, Amsterdam, The Netherlands, State University of New York Downstate Medical Center, and Institut Pasteur de Lille and Faculte de Pharmacie, France.

Karen Richardson | EurekAlert!
Further information:
http://www.wfubmc.edu

More articles from Life Sciences:

nachricht Are there sustainable solutions in dealing with dwindling phosphorus resources?
16.10.2017 | Leibniz-Institut für Nutzierbiologie (FBN)

nachricht Strange undertakings: ant queens bury dead to prevent disease
13.10.2017 | Institute of Science and Technology Austria

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

Im Focus: New nanomaterial can extract hydrogen fuel from seawater

Hybrid material converts more sunlight and can weather seawater's harsh conditions

It's possible to produce hydrogen to power fuel cells by extracting the gas from seawater, but the electricity required to do it makes the process costly. UCF...

Im Focus: Small collisions make big impact on Mercury's thin atmosphere

Mercury, our smallest planetary neighbor, has very little to call an atmosphere, but it does have a strange weather pattern: morning micro-meteor showers.

Recent modeling along with previously published results from NASA's MESSENGER spacecraft -- short for Mercury Surface, Space Environment, Geochemistry and...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

Conference Week RRR2017 on Renewable Resources from Wet and Rewetted Peatlands

28.09.2017 | Event News

 
Latest News

A single photon reveals quantum entanglement of 16 million atoms

16.10.2017 | Physics and Astronomy

The melting ice makes the sea around Greenland less saline

16.10.2017 | Earth Sciences

On the generation of solar spicules and Alfvenic waves

16.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>