Featured Research

from universities, journals, and other organizations

Bacteria help explain why stress, fear trigger heart attacks

Date:
June 10, 2014
Source:
American Society for Microbiology
Summary:
The axiom that stress, emotional shock, or overexertion may trigger heart attacks in vulnerable people may now be explainable, researchers say. Hormones released during these events appear to cause bacterial biofilms on arterial walls to disperse, allowing plaque deposits to rupture into the bloodstream, according to research.

Bacteria stained with a fluorescent bacterial DNA probe show up as red biofilm microcolonies within the green tissues of a diseased carotid arterial wall.
Credit: David Davies, University of Binghamton

Scientists believe they have an explanation for the axiom that stress, emotional shock, or overexertion may trigger heart attacks in vulnerable people. Hormones released during these events appear to cause bacterial biofilms on arterial walls to disperse, allowing plaque deposits to rupture into the bloodstream, according to research published in published in mBio, the online open-access journal of the American Society for Microbiology.

Related Articles


"Our hypothesis fitted with the observation that heart attack and stroke often occur following an event where elevated levels of catecholamine hormones are released into the blood and tissues, such as occurs during sudden emotional shock or stress, sudden exertion or over-exertion" said David Davies of Binghamton University, Binghamton, New York, an author on the study.

Davies and his colleagues isolated and cultured different species of bacteria from diseased carotid arteries that had been removed from patients with atherosclerosis. Their results showed multiple bacterial species living as biofilms in the walls of every atherosclerotic (plaque-covered) carotid artery tested.

In normal conditions, biofilms are adherent microbial communities that are resistant to antibiotic treatment and clearance by the immune system. However, upon receiving a molecular signal, biofilms undergo dispersion, releasing enzymes to digest the scaffolding that maintains the bacteria within the biofilm. These enzymes have the potential to digest the nearby tissues that prevent the arterial plaque deposit from rupturing into the bloodstream.

According to Davies, this could provide a scientific explanation for the long-held belief that heart attacks can be triggered by a stress, a sudden shock, or overexertion.

To test this theory they added norepinephrine, at a level that would be found in the body following stress or exertion, to biofilms formed on the inner walls of silicone tubing.

"At least one species of bacteria -- Pseudomonas aeruginosa -- commonly associated with carotid arteries in our studies, was able to undergo a biofilm dispersion response when exposed to norepinephrine, a hormone responsible for the fight-or-flight response in humans," said Davies. Because the biofilms are closely bound to arterial plaques, the dispersal of a biofilm could cause the sudden release of the surrounding arterial plaque, triggering a heart attack.

To their knowledge, this is the first direct observation of biofilm bacteria within a carotid arterial plaque deposit, says Davies. This research suggests that bacteria should be considered to be part of the overall pathology of atherosclerosis and management of bacteria within an arterial plaque lesion may be as important as managing cholesterol.


Story Source:

The above story is based on materials provided by American Society for Microbiology. Note: Materials may be edited for content and length.


Journal Reference:

  1. Bernard B. Lanter, Karin Sauer and David G. Davies. Bacteria Present in Carotid Arterial Plaques Are Found as Biofilm Deposits Which May Contribute to Enhanced Risk of Plaque Rupture. mBio, June 2014 DOI: 10.1128/mBio.01206-14

Cite This Page:

American Society for Microbiology. "Bacteria help explain why stress, fear trigger heart attacks." ScienceDaily. ScienceDaily, 10 June 2014. <www.sciencedaily.com/releases/2014/06/140610102010.htm>.
American Society for Microbiology. (2014, June 10). Bacteria help explain why stress, fear trigger heart attacks. ScienceDaily. Retrieved February 27, 2015 from www.sciencedaily.com/releases/2014/06/140610102010.htm
American Society for Microbiology. "Bacteria help explain why stress, fear trigger heart attacks." ScienceDaily. www.sciencedaily.com/releases/2014/06/140610102010.htm (accessed February 27, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Friday, February 27, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Amazon Keeps Its Green Thanks To The Sahara Desert

The Amazon Keeps Its Green Thanks To The Sahara Desert

Newsy (Feb. 25, 2015) Satellite data shows the Amazon rainforest supports its lush flora with a little help from Sahara Desert dust. Video provided by Newsy
Powered by NewsLook.com
Mayor Says District of Columbia to Go Ahead With Pot Legalization

Mayor Says District of Columbia to Go Ahead With Pot Legalization

Reuters - News Video Online (Feb. 25, 2015) Washington&apos;s mayor says the District of Columbia will move forward with marijuana legalization, despite pushback from Congress. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Marijuana Nowhere Near As Deadly As Alcohol: Study

Marijuana Nowhere Near As Deadly As Alcohol: Study

Newsy (Feb. 25, 2015) A new study says marijuana is about 114 times less deadly than alcohol. Video provided by Newsy
Powered by NewsLook.com
Fox With Horrifying Injury Rescued and Released Back Into the Wild

Fox With Horrifying Injury Rescued and Released Back Into the Wild

RightThisMinute (Feb. 25, 2015) This wounded fox knew what she was doing when she wandered into the yard of a nature photographer. The photographer got "Scamp" immediately in the hands of Wildlife Aid and she was released back into the wild in no time. Video provided by RightThisMinute
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


Plants & Animals

Earth & Climate

Fossils & Ruins

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