Featured Research

from universities, journals, and other organizations

New Gene May Play Important Role In Regulating HDL, The 'Good' Cholesterol

Date:
April 2, 1999
Source:
University Of Pennsylvania Medical Center
Summary:
A team of researchers from the University of Pennsylvania Medical Center and Rhone-Poulenc Rorer has identified a new human gene that may figure prominently in the regulation of cholesterol levels in the body. When the gene was experimentally overexpressed in mice, levels of the form of cholesterol called high-density lipoprotein, or HDL, dropped to nearly undetectable levels, a condition that would be associated with high cardiovascular disease risk in humans.

A team of researchers from the University of Pennsylvania Medical Center and Rhone-Poulenc Rorer has identified a new human gene that may figure prominently in the regulation of cholesterol levels in the body. When the gene was experimentally overexpressed in mice, levels of the form of cholesterol called high-density lipoprotein, or HDL, dropped to nearly undetectable levels, a condition that would be associated with high cardiovascular disease risk in humans. A report on the new findings appears in the April issue of Nature Genetics.

Related Articles


"HDL is a very powerful protector against heart disease and stroke, and we think this new gene could be a major player in determining HDL levels," says Daniel J. Rader, MD, an assistant professor of medicine and senior author on the report. "Too much activity on the part of this gene, for whatever reason, might lead to lowered HDL levels and higher cardiovascular disease risk."

While high overall levels of cholesterol in the blood have long been linked to elevated cardiovascular disease risk, two distinct forms of cholesterol are involved, each performing different duties in the body. Low-density lipoprotein (LDL) - sometimes called the bad cholesterol - is produced by the liver and ferries fats to the muscles, the heart, and other tissues. Unchecked, this process can lead to the formation of dangerous deposits in the arteries that can disrupt or block blood flow. HDL - referred to as the good cholesterol -- is also produced by the liver and is responsible for returning fats from tissues in the body to the liver for reprocessing or elimination. Dramatically lowered HDL levels could, therefore, lead to a health crisis in time.

Scientists have known that at least 50 percent of the variation in HDL cholesterol levels in the body depends on genetic factors. The specific genes involved have been unknown, however, so the current findings represent a potentially important advance toward understanding processes that contribute significantly to cardiovascular disease risk.

The discovery also suggests new directions for the development of pharmacological therapies for people with too-high overall cholesterol levels. "Administration of a drug able to inhibit the protein produced by this gene could be a very useful approach to raising HDL levels and preventing heart disease," according to Rader.

The protein produced by the new gene becomes the third member of a group of enzymes called triacylglyerol lipases, known to influence HDL metabolism. It is produced by endothelial cells, a subset of cells that includes those that line vessels and arteries, and is called endothelial lipase (EL).

Researchers at Rhone-Poulenc Rorer, led by Michael Jaye, PhD, a senior scientist at the company and lead author on the study, originally purified the EL protein and cloned the new gene. The Penn scientists, led by Rader, further characterized the gene and the EL protein, performing a series of experiments in mice that demonstrated the protein's likely role in HDL regulation.

For the mouse studies, Rader's group used gene transfer techniques. They stripped an adenovirus of its disease-causing genes - adenoviruses are usually associated with colds and upper respiratory infections - reloading it with the DNA needed to produce the new EL protein. They then injected the recombinant adenovirus into several strains of mice. In each case, expression of the new gene resulted in significant reductions of HDL levels in the blood.

The Penn coauthors on the study are Dawn Marchadier and Cyrille Maugcais. Additional authors at Rhone-Poulenc Rorer are Kevin J. Lynch, John Krawiec, Kim Doan, Victoria South, Dilip Amin, and Mark Perrone.

###

The University of Pennsylvania Medical Center's sponsored research and training ranks second in the United States based on grant support from the National Institutes of Health, the primary funder of biomedical research and training in the nation -- $201 million in federal fiscal year 1998. In addition, the institution continued to maintain the highest average annual growth rate since 1991 - 13.2 percent - of the top ten U.S. academic medical centers. News releases from the University of Pennsylvania Medical Center are available to reporters by direct e-mail, fax, or U.S. mail, upon request. They are also posted electronically to the medical center's home page.


Story Source:

The above story is based on materials provided by University Of Pennsylvania Medical Center. Note: Materials may be edited for content and length.


Cite This Page:

University Of Pennsylvania Medical Center. "New Gene May Play Important Role In Regulating HDL, The 'Good' Cholesterol." ScienceDaily. ScienceDaily, 2 April 1999. <www.sciencedaily.com/releases/1999/04/990402074125.htm>.
University Of Pennsylvania Medical Center. (1999, April 2). New Gene May Play Important Role In Regulating HDL, The 'Good' Cholesterol. ScienceDaily. Retrieved October 26, 2014 from www.sciencedaily.com/releases/1999/04/990402074125.htm
University Of Pennsylvania Medical Center. "New Gene May Play Important Role In Regulating HDL, The 'Good' Cholesterol." ScienceDaily. www.sciencedaily.com/releases/1999/04/990402074125.htm (accessed October 26, 2014).

Share This



More Health & Medicine News

Sunday, October 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Texas Nurse Nina Pham Cured of Ebola

Texas Nurse Nina Pham Cured of Ebola

AFP (Oct. 25, 2014) — An American nurse who contracted Ebola while caring for a Liberian patient in Texas has been declared free of the virus and will leave the hospital. Duration: 01:01 Video provided by AFP
Powered by NewsLook.com
Toxin-Packed Stem Cells Used To Kill Cancer

Toxin-Packed Stem Cells Used To Kill Cancer

Newsy (Oct. 25, 2014) — A Harvard University Research Team created genetically engineered stem cells that are able to kill cancer cells, while leaving other cells unharmed. Video provided by Newsy
Powered by NewsLook.com
IKEA Desk Converts From Standing to Sitting With One Button

IKEA Desk Converts From Standing to Sitting With One Button

Buzz60 (Oct. 24, 2014) — IKEA is out with a new convertible desk that can convert from a sitting desk to a standing one with just the push of a button. Jen Markham explains. Video provided by Buzz60
Powered by NewsLook.com
Ebola Protective Suits Being Made in China

Ebola Protective Suits Being Made in China

AFP (Oct. 24, 2014) — A factory in China is busy making Ebola protective suits for healthcare workers and others fighting the spread of the virus. Duration: 00:38 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins