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 'Lipid asymmetry' plays key role in activating immune cells
20.02.2018 | Biophysical Society

nachricht New printing technique uses cells and molecules to recreate biological structures
20.02.2018 | Queen Mary University of London

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

'Lipid asymmetry' plays key role in activating immune cells

20.02.2018 | Life Sciences

MRI technique differentiates benign breast lesions from malignancies

20.02.2018 | Medical Engineering

Major discovery in controlling quantum states of single atoms

20.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>