Navigation Links
When 'Good' Cholesterol Goes Bad
Date:8/22/2007

HDL analysis uncovers a dark side, but also a new way it fights heart disease

WEDNESDAY, Aug. 22 (HealthDay News) -- It looks like HDL, the "good" cholesterol that supposedly protects against cardiovascular disease, might have a harmful side.

New research suggests that some people's HDL is more protective for their hearts than others, and that certain proteins in HDL can exacerbate vessel damage, particularly in people with heart disease.

But there's good news, too, as scientists uncover a new means by which HDL boosts cardiovascular health.

The findings were to be reported Wednesday at the American Chemical Society's annual meeting in Boston.

So far, the cholesterol story has been a relatively simple one in which "bad" low-density lipoprotein (LDL) cholesterol formed plaques that eventually blocked arteries, while "good" high-density lipoprotein (HDL) cholesterol worked to carry away those deposits, explained Dr. Jay Heinecke, a professor of medicine at the University of Washington, Seattle.

"But in the last few years there has been growing evidence that HDL does other things," he said. "In particular, it may be inhibiting inflammation."

Inflammation is the major villain in the new picture. Arteries are not only blocked because of the gradual growth of plaque. Instead, there comes a moment when plaque ruptures, causing a clot to form and block blood flow, Heinecke said. Proteins called proteases play a major role in these ruptures.

"What we found in HDL is a whole series of proteins that inhibit proteases," Heinecke said, describing what he called the most detailed analysis to date of HDL's protein composition. "So, part of [HDL's] protective effect is to prevent rupture."

The Seattle analysis also found a lot of previously unrecognized HDL proteins, including 22 that play roles in cholesterol metabolism.

One finding of particular significance is that HDL protein composition can be different in people who have heart disease and those who do not -- meaning that some of the supposedly "good" HDL proteins are really bad.

"With LDL cholesterol it's simple -- the lower the better," Heinecke said. "With HDL, it's much more complicated. The protein composition of people with and without heart disease is different."

So, measuring blood levels of LDL and HDL cholesterol is not as predictive of cardiac risk, as has been assumed, Heinecke stressed. "Protein composition [in HDL cholesterol] may be a better handle on whether someone is at risk," he added.

Animal studies have found "dysfunctional" HDL cholesterol, which works against coronary health, Heinecke said. "It is proposed that the same thing is going on in humans," he noted.

The finding of dysfunctional HDL proteins helps explain why a major pharmaceutical company ended work on an HDL-boosting drug when it was found to actually increase deaths and heart problems in a human trial.

A better understanding of the protein components of HDL could lead to more accurate tests for heart disease, Heinecke said. "Most people who have heart attacks have normal levels of HDL, so the composition of the HDL may tell who is vulnerable," he said.

Future cardiac therapy may include LDL-lowering statins and new drugs aimed at the damaging components of HDL cholesterol, Heinecke said.

More information

There's more on HDL and LDL cholesterol at the American Heart Association.



SOURCES: Jay Heinecke, M.D., professor, medicine, University of Washington, Seattle; Aug. 22, 2007, American Chemical Society annual meeting, Boston


'/>"/>
Copyright©2007 ScoutNews,LLC.
All rights reserved

Related medicine news :

1. Dietary phytonutrients – Secret for the good food to taste ba
2. Good sleep enhances task performance
3. Grains do good
4. Why running noses are a good thing
5. Beer does good
6. Eat Like a Greek for Good Health
7. How Good Are Vitamins For You ?
8. Experts State Strategies To Increase Good Cholesterol
9. Olive oil does good
10. Good News For Women With Gestational Diabetes
11. Step Aerobics Increases good cholesterol
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:12/2/2016)... ... December 02, 2016 , ... ... launch of its 60-day free trial program for all of the company’s desktop ... offer a truly hassle free experience. , FlexiSpot’s unique desktop risers use an ...
(Date:12/2/2016)... ... ... The annual time frame to change Medicare health and prescription drug coverage, known ... Medicare beneficiaries who are looking to switch from their current plan to a Medicare ... during this period order for their new policy to go into effect in 2017. ...
(Date:12/2/2016)... ... December 02, 2016 , ... With the number of pain management programs available ... must find the one that works for them. When an inventor from Suisun City, ... worked and decided to share it with others. , He developed a prototype for ...
(Date:12/2/2016)... ... December 02, 2016 , ... Dr. Raffi Hovsepian, a leading ... the 2016 “Guide to America’s Top Plastic Surgeons” for seven consecutive years. The ... education, experience, and professional associations. , One the most frequently honored surgeons ...
(Date:12/2/2016)... ... December 02, 2016 , ... Mediaplanet is proud to announce ... covers the innovative treatments, therapeutic technologies, and revolutionized nutrition that are helping patients ... life 6 years in the last 3 decades,” says Dr. Valentine Fuster, a ...
Breaking Medicine News(10 mins):
(Date:12/2/2016)... MONMOUTH JUNCTION, N.J. , Dec. 2, 2016 /PRNewswire/ ... critical care immunotherapy leader commercializing its European Union approved ... in critically-ill and cardiac surgery patients worldwide, announced that ... present at the 9th Annual LD Micro Main ... 8 th , 2016 at the Luxe Sunset Boulevard ...
(Date:12/2/2016)... LYME, Conn. , Dec. 1, 2016  Today, ... has announced the honor of being selected as winners ... include: Simpson Healthcare Executives Website at the PLATINUM level, ... Conversations Training Module at the GOLD Level, and our ... At Simpson Healthcare Executives, we are excited ...
(Date:12/2/2016)... YORK , December 2, 2016 ... of its past losses following Trump,s victory early in ... potential, and fund managers are now predicting an uptick ... at four equities to see how they have fared ... CLDX ), Amicus Therapeutics Inc. (NASDAQ: ...
Breaking Medicine Technology: