Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Enzyme controls ’good cholesterol’

27.02.2003


A recently discovered enzyme called endothelial lipase regulates the structure, metabolism and blood concentration of high density lipoprotein (HDL), the so-called "good cholesterol," said researchers from Baylor College of Medicine in a report in the online version of the Proceedings of the National Academy of Sciences.



In a series of studies in mice, Dr. Lawrence Chan, chief of the section of endocrinology and metabolism at Baylor, his co-workers and colleagues from the section of cardiology and atherosclerosis have found that when mice lack this enzyme, the particles of HDL in their blood are much larger than normal.

"We don’t know if it is good or bad that the HDL becomes larger," said Chan. "We were always taught that high levels of HDL are good for you because HDL carries cholesterol from the outer areas of the body back to the liver where it is excreted as bile."


High levels of HDL may also inhibit inflammation, a newly accepted factor in coronary heart disease, Chan said.

"It also protects the vascular wall," he said. "It may also slow down the oxidation of low density lipoprotein (the so-called bad cholesterol). Oxidized LDL is very bad."

A variant of the enzyme that is found in approximately 26 percent of people is associated with high levels of HDL, he said. He and his colleagues are studying the fate of patients with this type of enzyme to determine whether it is beneficial or not.

Once they determine whether the variant form of HDL is good or bad, it can become a target for drug developers who will attempt to manipulate levels of "good" cholesterol through this mechanism.

One concern is that the larger particles of HDL might slow the transport of cholesterol back to the liver, which probably would not be good, said Chan. While HDL might have all the good actions including working against inflammation and protecting the vascular wall, that would have to be balanced against the interruption of cholesterol transport to the liver.

In his experiments, he found that metabolism of HDL is a lot slower without the enzyme.

"That’s why the concentration goes up as the HDL accumulates," he said.

Others who participated in the study included Drs. Ke Ma, Mehmet Cilingiroglu, Christie M. Ballantyne and Ali J. Marian, all of Baylor, and Dr. James Otvos of LipoScience of Raleigh, NC.

Anissa Anderson Orr | EurekAlert!
Further information:
http://research.bcm.tmc.edu/

More articles from Life Sciences:

nachricht Water world
20.11.2017 | Washington University in St. Louis

nachricht Carefully crafted light pulses control neuron activity
20.11.2017 | University of Illinois at Urbana-Champaign

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Antarctic landscape insights keep ice loss forecasts on the radar

20.11.2017 | Earth Sciences

Filling the gap: High-latitude volcanic eruptions also have global impact

20.11.2017 | Earth Sciences

Water world

20.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>