Featured Research

from universities, journals, and other organizations

Researchers closer to understanding actions of cells involved in atherosclerosis

Date:
September 10, 2012
Source:
St. Michael's Hospital
Summary:
Researchers are one step closer to understanding why plaque bursts in coronary arteries and causes heart attacks.

Researchers at St. Michael's Hospital are one step closer to understanding why plaque bursts in coronary arteries and causes heart attacks.

The clue might be something called microRNA-145. MicroRNAs are short chains of bossy molecules that scientists are increasingly coming to realize control a wide variety of biological processes.

Dr. Subodh Verma, a cardiac surgeon at St. Michael's, published a paper in the journal Circulation September 10, describing for the first time how microRNA-145 gene therapy can drastically reduce the severity and progression of atherosclerosis in mice.

In addition this approach appeared to make the atherosclerotic plaque more stable and less prone to burst.

Atherosclerosis, commonly called hardening of the arteries, is a condition in which fat, cholesterol and other substances build up in the walls of arteries and form hard structures called plaques. It is the leading cause of death in Canada.

Dr. Verma said most heart attacks occur when plaques rupture like a broken eggshell and release their contents into the artery. Researchers are therefore looking for ways to reduce the size of plaques and make them more stable.

One of the key questions is what causes the outer layer of the plaque to finally burst -- a layer of smooth muscle cells known as the fibrous cap. These cells undergo "phenotypic transformation" in response to various stressful environments and cardiovascular risk factors, making them more likely to rupture and cause heart attacks. MicroRNA-145 is one of the factors that appear to play a critical role in preventing the transformation of vascular smooth muscle cells into rupture-prone cells.

In atherosclerosis-prone animals, microRNA-145-based gene therapy reduced the plaque size by approximately 50 per cent and increased the collagen content of the plaque and fibrous cap area by 40 to 50 per cent, indicating that this therapy can reduce plaque buildup and also make it less prone to rupture, the inciting event of heart attacks.

The researchers also found that in human atherosclerotic plaques, the amount of microRNA-145 was reduced compared to normal arteries that were free of plaque, providing supporting human insights to the animal study.

"Atherosclerosis continues to be the number one killer in modern societies and finding new ways to treat this problem are needed," said Dr. Verma.

Dr. Fina Lovren, a senior research associate at St Michael's Hospital, carried out the experimental work on this project under the direction of Dr. Verma.


Story Source:

The above story is based on materials provided by St. Michael's Hospital. The original article was written by Leslie Shepherd. Note: Materials may be edited for content and length.


Journal Reference:

  1. F. Lovren, Y. Pan, A. Quan, K. K. Singh, P. C. Shukla, N. Gupta, B. M. Steer, A. J. Ingram, M. Gupta, M. Al-Omran, H. Teoh, P. A. Marsden, S. Verma. MicroRNA-145 Targeted Therapy Reduces Atherosclerosis. Circulation, 2012; 126 (11_suppl_1): S81 DOI: 10.1161/CIRCULATIONAHA.111.084186

Cite This Page:

St. Michael's Hospital. "Researchers closer to understanding actions of cells involved in atherosclerosis." ScienceDaily. ScienceDaily, 10 September 2012. <www.sciencedaily.com/releases/2012/09/120910185759.htm>.
St. Michael's Hospital. (2012, September 10). Researchers closer to understanding actions of cells involved in atherosclerosis. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2012/09/120910185759.htm
St. Michael's Hospital. "Researchers closer to understanding actions of cells involved in atherosclerosis." ScienceDaily. www.sciencedaily.com/releases/2012/09/120910185759.htm (accessed July 31, 2014).

Share This




More Health & Medicine News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

House Republicans Vote to Sue Obama Over Healthcare Law

House Republicans Vote to Sue Obama Over Healthcare Law

Reuters - US Online Video (July 31, 2014) The Republican-led House of Representatives votes to sue President Obama, accusing him of overstepping his executive authority in making changes to the Affordable Care Act. Mana Rabiee reports. Video provided by Reuters
Powered by NewsLook.com
Despite Health Questions, E-Cigs Are Beneficial: Study

Despite Health Questions, E-Cigs Are Beneficial: Study

Newsy (July 31, 2014) Citing 81 previous studies, new research out of London suggests the benefits of smoking e-cigarettes instead of regular ones outweighs the risks. Video provided by Newsy
Powered by NewsLook.com
Dangerous Bacteria Kills One in Florida

Dangerous Bacteria Kills One in Florida

AP (July 31, 2014) Sarasota County, Florida health officials have issued a warning against eating raw oysters and exposing open wounds to coastal and inland waters after a dangerous bacteria killed one person and made another sick. (July 31) Video provided by AP
Powered by NewsLook.com
Health Insurers' Profits Slide

Health Insurers' Profits Slide

Reuters - Business Video Online (July 30, 2014) Obamacare-related costs were said to be behind the profit plunge at Wellpoint and Humana, but Wellpoint sees the new exchanges boosting its earnings for the full year. Fred Katayama reports. Video provided by Reuters
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