Featured Research

from universities, journals, and other organizations

Scientists Find That Heart Muscle Cells Regenerate After A Heart Attack

Date:
June 7, 2001
Source:
NIH/National Heart, Lung, And Blood Institute
Summary:
Challenging one of medicine's long-standing beliefs, a team of scientists funded by the National Heart, Lung, and Blood Institute (NHLBI) and the National Institute on Aging (NIA) has found the strongest evidence to date that human heart muscle cells regenerate after a heart attack.

Challenging one of medicine's long-standing beliefs, a team of scientists funded by the National Heart, Lung, and Blood Institute (NHLBI) and the National Institute on Aging (NIA) has found the strongest evidence to date that human heart muscle cells regenerate after a heart attack. In a paper published in the June 7 issue of the New England Journal of Medicine, scientists from New York Medical College in Valhalla, NY report their success in finding large scale replication of heart muscle cells in two regions of the heart, and in identifying several other key indicators of cell regeneration.

"It has long been assumed that when the heart is damaged — such as after a heart attack — heart muscle cells do not regenerate and the damage is permanent. This assumption has been challenged in recent years by evidence that heart muscle cells may in fact regenerate. Now, this latest research provides the most dramatic and clear-cut demonstration to date of heart cell regeneration after cardiac injury," says Claude Lenfant, M.D., director of the NHLBI, a component of the National Institutes of Health (NIH).

"With this landmark study, we have a new understanding of the heart that opens up the possibility of repairing heart muscle damage after a heart attack," he adds.

"This finding, if confirmed, may begin to clarify how hearts respond to the normal insults of aging through previously undetected repair mechanisms," says David Finkelstein, Ph.D., director of basic cardiovascular research at the NIA.

Piero Anversa, M.D., professor of medicine and director of the Cardiovascular Research Institute, and colleagues, studied myocytes (heart muscle cells) from the hearts of 13 patients, 4 to 12 days after their heart attacks, and from the hearts of 10 patients who did not have cardiovascular disease. Samples were obtained from the border zone near the site of the heart attack and from a more distant site from the damaged tissue.

By viewing these areas of the heart with a high resolution confocal microscope, Anversa and colleagues were able to measure the expression of Ki67, a protein found in the nucleus of dividing heart muscle cells. Ki67 is expressed during all phases of a cell's life cycle and is a strong indicator of cell division.

The scientists also obtained images of mitotic division and found other evidence of myoctye replication, including the formation of the "mitotic spindle," and "contractile ring," critical structural indicators of cell division.

Important evidence of myocardial repair was demonstrated by the mitotic index, a measurement of the degree of myocyte division. In comparison with normal hearts, the number of myoctyes multiplying in diseased hearts was 70 times higher in the border zone and 24 times higher in the remote myocardium.

The next challenge, according to Anversa, is to find the source of the dividing myoctyes. "Are these cells a sub-population of known cells that retain the capacity to divide, or are they multiplying cells that originate from stem cells present in the heart?" he asks.

"There are preliminary indications that primitive cells like stem cells exist in the human heart. Stem cells may have the ability to develop into the various cardiac cell types and form new healthy functioning myocardium. If we can prove the existence of cardiac stem cells and make these cells migrate to the region of tissue damage, we could conceivably improve the repair of damaged heart muscle and reduce heart failure," says Anversa.

Research on animal models supports this possibility. In the April 4 issue of Nature, the Anversa team and a colleague at the NIH reported that adult stem cells isolated from mouse bone and injected into a damaged mouse heart became functioning heart muscle by developing into myocytes and coronary vessels. Moreover, the newly formed tissue partially restored the heart's ability to pump blood.

Although a cardiac stem cell has not yet been identified, scientists have identified a neural stem cell in the brain.

"Why not the heart?" asks Anversa.


Story Source:

The above story is based on materials provided by NIH/National Heart, Lung, And Blood Institute. Note: Materials may be edited for content and length.


Cite This Page:

NIH/National Heart, Lung, And Blood Institute. "Scientists Find That Heart Muscle Cells Regenerate After A Heart Attack." ScienceDaily. ScienceDaily, 7 June 2001. <www.sciencedaily.com/releases/2001/06/010607075716.htm>.
NIH/National Heart, Lung, And Blood Institute. (2001, June 7). Scientists Find That Heart Muscle Cells Regenerate After A Heart Attack. ScienceDaily. Retrieved September 20, 2014 from www.sciencedaily.com/releases/2001/06/010607075716.htm
NIH/National Heart, Lung, And Blood Institute. "Scientists Find That Heart Muscle Cells Regenerate After A Heart Attack." ScienceDaily. www.sciencedaily.com/releases/2001/06/010607075716.htm (accessed September 20, 2014).

Share This



More Health & Medicine News

Saturday, September 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Could Grief Affect The Immune Systems Of Senior Citizens?

Could Grief Affect The Immune Systems Of Senior Citizens?

Newsy (Sep. 19, 2014) The study found elderly people are much more likely to become susceptible to infection than younger adults going though a similar situation. Video provided by Newsy
Powered by NewsLook.com
Jury Delivers Verdict in Salmonella Trial

Jury Delivers Verdict in Salmonella Trial

AP (Sep. 19, 2014) A federal jury has convicted three people in connection with an outbreak of salmonella poisoning five years ago that sickened hundreds of people and was linked to a number of deaths. (Sept. 19) Video provided by AP
Powered by NewsLook.com
How The 'Angelina Jolie Effect' Increased Cancer Screenings

How The 'Angelina Jolie Effect' Increased Cancer Screenings

Newsy (Sep. 19, 2014) Angelina's Jolie's decision to undergo a preventative mastectomy in 2013 inspired many women to seek early screenings for the disease. Video provided by Newsy
Powered by NewsLook.com
The Cost of Ebola

The Cost of Ebola

Reuters - Business Video Online (Sep. 18, 2014) As Sierra Leone prepares for a three-day "lockdown" in its latest bid to stem the spread of Ebola, Ciara Lee looks at the financial implications of fighting the largest ever outbreak of the disease. 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