Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Molecule that usually protects infection-fighting cells may cause plaque deposits inside arteries

16.03.2005


A molecule that usually protects the body’s infection-fighting cells might also contribute to fatty buildups that coat arteries and lead to heart disease, UT Southwestern Medical Center researchers have found.



The molecule, called apoptosis inhibitor of macrophage or AIM, inhibits cell death in macrophages, which circulate in the bloodstream and help the body fend off infection and foreign substances. The AIM-protected macrophages go on to encourage buildup of fats on the interior walls of arteries, according to Dr. Toru Miyazaki, senior author of a study that appears in the March issue of the journal Cell Metabolism.

" We found that AIM is highly expressed in certain macrophages and that lack of AIM dramatically decreased early atherosclerotic lesion development in mice," Dr. Miyazaki said. "These results may imply a novel therapeutic application of AIM regulation for prevention of atherosclerosis in the future. Most importantly and attractively for patients, this approach may not need dietary restriction."


Dr. Miyazaki, associate professor in the Center for Immunology and of pathology, and his colleagues first discovered the protective role of AIM six years ago. In the current study, scientists exposed mice lacking AIM to a fatty diet that would normally induce atherosclerosis. After several weeks, researchers found little to no atherosclerotic lesions. Comparatively, in mice that had normal AIM function, there was marked presence of plaque deposits in the arteries following a diet of high-fat food.

"This was dramatic evidence that showed suppressing AIM function translates into prevention of atherosclerosis," Dr. Miyazaki said.

Atherosclerosis, known as "hardening of the arteries," occurs when the inside walls of an artery become thicker and less elastic. This narrows the space for blood flow and can lead to angina and heart attacks in some people. Fatty buildups occur on the inner lining of an artery and gradually thicken into a plaque. As plaque grows, it narrows the artery more and more. When the plaque ruptures, blood clots form that can block the artery entirely.

Low-density lipoprotein is transported inside arteries by macrophages, which engulf the cholesterol through a process called oxidation. Macrophages produce pro-inflammatory substances, which cause a secondary effect, encouraging other cells to accumulate and worsen plaque buildup in arteries.

"The oxidized lipids are cleared out by macrophage cells, but the lipids themselves are very toxic to cells and promote apoptosis (cell death)," Dr. Miyazaki said. "Therefore AIM production is a self-defense mechanism for macrophage cells, but interestingly, is in turn detrimental for the body."

Atherosclerosis is a contributing factor to a number of cardiovascular diseases - the No. 1 cause of death among people in the United States. It is also highly associated with other risk factors such as smoking, obesity and diets high in fat and cholesterol.

UT Southwestern researchers involved in the study included Dr. Satoko Arai, postdoctoral researcher in the Center for Immunology; Angie Bookout, researcher; John Shelton, research scientist in internal medicine; and Dr. David Mangelsdorf, professor of pharmacology and Howard Hughes Medical Institute investigator. The University of California, Los Angeles, also contributed to this study.

The two-year study was funded by the Juvenile Diabetes Research Foundation and the National Institutes of Health.

Katherine Morales | EurekAlert!
Further information:
http://www.utsouthwestern.edu

More articles from Life Sciences:

nachricht Researchers uncover protein-based “cancer signature”
05.12.2016 | Universität Basel

nachricht The Nagoya Protocol Creates Disadvantages for Many Countries when Applied to Microorganisms
05.12.2016 | Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

IHP presents the fastest silicon-based transistor in the world

05.12.2016 | Power and Electrical Engineering

InLight study: insights into chemical processes using light

05.12.2016 | Materials Sciences

High-precision magnetic field sensing

05.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>