Featured Research

from universities, journals, and other organizations

Free-radical Busting Antioxidants Might Not Promote Healthy Hearts

Date:
April 10, 2006
Source:
Journal of Experimental Medicine
Summary:
Antioxidants, such as beta-carotene and Vitamin E, have been touted for their ability to protect against heart disease. This protective effect is attributed to their ability to prevent the oxidation of bad cholesterol -- a process thought to contribute to the build-up of disease-causing fatty deposits on artery walls. But a new study, published online on April 10 in The Journal of Experimental Medicine, suggests that the heart-healthy effect of one antioxidant has nothing to do with inhibiting oxidation.

Antioxidants, such as beta-carotene and Vitamin E, have been touted for their ability to protect against heart disease. This protective effect is attributed to their ability to prevent the oxidation of bad cholesterol by free radicals -- a process thought to contribute to the build-up of disease-causing fatty deposits on artery walls. But a new study, published online on April 10 in The Journal of Experimental Medicine, suggests that the heart-healthy effect of one antioxidant has little to do with cholesterol oxidation.

A group of researchers at the University of New South Wales in Australia, led by Roland Stocker, studied a cholesterol-lowering drug called Probucol (Lorelco) in laboratory rodents with vascular disease. Probucol reduces the risk of heart disease in humans, but is no longer prescribed in the US and Australia because of adverse side effects: a tendency to lower good cholesterol along with the bad and the potential to induce an irregular heartbeat. Probucol is still available in Canada and Europe.

In their new study, Stocker and his colleagues show that the protective effect of probucol has nothing to do with its ability to scavenge oxygen free radicals, as the free radical-busting part of the drug alone was ineffective in protecting animals against heart disease. Instead, a different part of the probucol molecule was doing the beneficial work.

In fact, contrary to widely accepted opinion, the group found no relationship between the levels of oxidized cholesterol in blood vessels and the severity of heart disease. This might help explain the disappointing results of clinical trials with other free radical-scavenging antioxidants, such as Vitamin E, which have shown no protective effect against heart disease in humans.

The protective effect of these compounds depended on the induction of a cellular enzyme called heme oxygenase-1 (HO-1). HO-1 is known to protect against atherosclerosis in animal models, although the mechanism is not completely clear. Not surprisingly, HO-1 was not induced by Vitamin E.

Drugs closely related to probucol that contain the protective part of the drug were just as protective as the original drug. If these probucol relatives -- one of which is now being tested in humans -- are free of side effects, they may provide a more effective alternative to current therapies.



Story Source:

The above story is based on materials provided by Journal of Experimental Medicine. Note: Materials may be edited for content and length.


Cite This Page:

Journal of Experimental Medicine. "Free-radical Busting Antioxidants Might Not Promote Healthy Hearts." ScienceDaily. ScienceDaily, 10 April 2006. <www.sciencedaily.com/releases/2006/04/060410112017.htm>.
Journal of Experimental Medicine. (2006, April 10). Free-radical Busting Antioxidants Might Not Promote Healthy Hearts. ScienceDaily. Retrieved April 20, 2014 from www.sciencedaily.com/releases/2006/04/060410112017.htm
Journal of Experimental Medicine. "Free-radical Busting Antioxidants Might Not Promote Healthy Hearts." ScienceDaily. www.sciencedaily.com/releases/2006/04/060410112017.htm (accessed April 20, 2014).

Share This



More Health & Medicine News

Sunday, April 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Nine-Month-Old Baby Can't Open His Mouth

Nine-Month-Old Baby Can't Open His Mouth

Newsy (Apr. 19, 2014) Nine-month-old Wyatt Scott was born with a rare disorder called congenital trismus, which prevents him from opening his mouth. Video provided by Newsy
Powered by NewsLook.com
'Holy Grail' Of Weight Loss? New Find Could Be It

'Holy Grail' Of Weight Loss? New Find Could Be It

Newsy (Apr. 18, 2014) In a potential breakthrough for future obesity treatments, scientists have used MRI scans to pinpoint brown fat in a living adult for the first time. Video provided by Newsy
Powered by NewsLook.com
Little Progress Made In Fighting Food Poisoning, CDC Says

Little Progress Made In Fighting Food Poisoning, CDC Says

Newsy (Apr. 18, 2014) A new report shows rates of two foodborne infections increased in the U.S. in recent years, while salmonella actually dropped 9 percent. Video provided by Newsy
Powered by NewsLook.com
Scientists Create Stem Cells From Adult Skin Cells

Scientists Create Stem Cells From Adult Skin Cells

Newsy (Apr. 17, 2014) The breakthrough could mean a cure for some serious diseases and even the possibility of human cloning, but it's all still a way off. Video provided by Newsy
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:
from the past week

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