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 Link Discovered between Immune System, Brain Structure and Memory
26.04.2017 | Universität Basel

nachricht Researchers develop eco-friendly, 4-in-1 catalyst
25.04.2017 | Brown University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Scientist invents way to trigger artificial photosynthesis to clean air

26.04.2017 | Materials Sciences

Ammonium nitrogen input increases the synthesis of anticarcinogenic compounds in broccoli

26.04.2017 | Agricultural and Forestry Science

SwRI-led team discovers lull in Mars' giant impact history

26.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>