Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Jefferson scientists unlocking secrets of cholesterol transport in body

24.02.2004


Scientists at Jefferson Medical College and Jefferson’s Kimmel Cancer Center have discovered one part of the mechanism behind a popular anti-cholesterol drug.



Steven Farber, Ph.D., assistant professor of microbiology and immunology at Jefferson Medical College of Thomas Jefferson University in Philadelphia, Eric Smart, Ph.D., at the University of Kentucky and their co-workers have found that treating hypercholesterolemic mice with the drug ezetimibe (Zetia) disrupts a complex of two proteins in the intestine. At the same time, they used "antisense" molecules to prevent the formation of the complex in zebrafish, resulting in impaired cholesterol absorption in the intestine. The results suggest that these proteins are integral parts of an unidentified cholesterol transport system in the intestine.

A better understanding of the mechanisms behind cholesterol transport and absorption in the intestine could lead to improved therapies for obesity, diabetes and cardiovascular disease.


Dr. Farber and his colleagues report their findings February 23, 2004 in the Proceedings of the National Academy of Sciences. Specifically, the researchers found that two proteins – Caveolin 1 and Annexin 2 – were bound extremely tightly in the intestines. When this association was disrupted in zebrafish embryos, they absorbed a cholesterol "analog" more poorly. The scientists also found a similar close association of these proteins in mouse intestinal cells not found in other cells.

When the team treated mice that were fed a high fat Western diet with Zetia, the two proteins separated. "This was truly an unexpected result," Dr. Farber says. "How cholesterol levels can influence the ability of Zetia to disrupt the complex remains a mystery," he says, adding that both he and Dr. Smart plan to study the question in the near future. Ezetimibe blocks cholesterol absorption in the intestines, and as a result, scientists have inferred the existence of a cholesterol transport system in the intestines. The drug works differently than the popular statins, which inhibit cholesterol synthesis in the liver. But no one has identified molecularly how ezetimibe works.

"We’ve identified the components of the intestine that likely mediate the effect of Zetia," Dr. Farber says. "These proteins probably act as a shuttling system that moves cholesterol through cells." But, he adds, multiple proteins could be involved.

In a recent paper just published in the journal Science, researchers at Schering-Plough Research Institute demonstrated that mice that lack a protein, NPC1L1, absorb very little cholesterol, though the scientists failed to show a direct interaction between Zetia and NPC1L1. Dr. Farber’s group was able to show that Calveolin 1 directly binds to Zetia. "This is a very exciting week in the lipid biology field," he says. "It’s possible that NPC1L1 and our protein complex work together in some yet to be discovered manner."

Given the findings of the two papers, he says, "Now you could try different drugs to see which ones break up the complex, and perhaps not only make better drugs, but improve our understanding of the genes that regulate this process."


Additional Contact Information: Steve Benowitz or Phyllis Fisher
After Hours: 215-955-6060

Steve Benowitz | EurekAlert!
Further information:
http://www.tju.edu/

More articles from Life Sciences:

nachricht What happens in the cell nucleus after fertilization
06.12.2016 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

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

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

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,...

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

Robot on demand: Mobile machining of aircraft components with high precision

06.12.2016 | Power and Electrical Engineering

A new dead zone in the Indian Ocean could impact future marine nutrient balance

06.12.2016 | Earth Sciences

Significantly more productivity in USP lasers

06.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>