Featured Research

from universities, journals, and other organizations

Collagen patch speeds repair of damaged heart tissue in mice

Date:
August 29, 2013
Source:
Stanford University Medical Center
Summary:
Researchers have developed a patch composed of structurally modified collagen that can be grafted onto damaged heart tissue. Their studies in mice have demonstrated that the patch not only speeds generation of new cells and blood vessels in the damaged area, it also limits the degree of tissue damage resulting from the original trauma.

You can't resurrect a dead cell anymore than you can breathe life into a brick, regardless of what you may have gleaned from zombie movies and Dr. Frankenstein. So when heart cells die from lack of blood flow during a heart attack, replacing those dead cells is vital to the heart muscle's recovery.

But muscle tissue in the adult human heart has a limited capacity to heal, which has spurred researchers to try to give the healing process a boost. Various methods of transplanting healthy cells into a damaged heart have been tried, but have yet to yield consistent success in promoting healing.

Now, researchers at the Stanford University School of Medicine and Lucile Packard Children's Hospital have developed a patch composed of structurally modified collagen that can be grafted onto damaged heart tissue. Their studies in mice have demonstrated that the patch not only speeds generation of new cells and blood vessels in the damaged area, it also limits the degree of tissue damage resulting from the original trauma.

The key, according to Pilar Ruiz-Lozano, PhD, associate professor of pediatrics, is that the patch doesn't seek to replace the dead heart-muscle cells. Instead, it replaces the epicardium, the outer layer of heart tissue, which is not muscle tissue, but which protects and supports the heart muscle, or myocardium.

"This synthetic tissue has the mechanical properties of the embryonic epicardium," said Ruiz-Lozano, who is the senior author of a study that describes the researchers' findings. The study will be published online Aug. 29 in Biomaterials. Vahid Serpooshan, PhD, a postdoctoral scholar in cardiology, is the lead author.

Embryonic epicardium is significantly more flexible than adult epicardium, but more rigid and structured than existing materials, making it more conducive to growth of new tissue. "We paid tremendous attention to the physical properties of the materials and how their elasticity could modify the function of the heart," Ruiz-Lozano said.

The epicardium -- or its artificial replacement -- has to allow the cell migration and proliferation needed to rebuild damaged tissue, as well as be sufficiently permeable to allow nutrients and cellular waste to pass through the network of blood vessels that weaves through it. The mesh-like structure of collagen fibers in the patch has those attributes, serving to support and guide new growth. Like sugar snap pea vines climbing a garden trellis, blood vessels spread through the interlacing fibers of the patch, blossoming new muscle cells like peapods as they proliferate.

Collagen is a fibrous protein found in connective tissue, including skin, bone, cartilage and tendons, as well as in the epicardium. Because the patch is made of acellular collagen, meaning it contains no cells, recipient animals do not need to be immunosuppressed to avoid rejection. With time, the collagen gets absorbed into the organ.

Compared with control mice that received no patch, mice that were given the patch promptly after experiencing a surgically induced heart attack showed significant improvement in overall cardiac function in echocardiograms two weeks later. The patched hearts showed more migration of cells to the site of the injury four weeks after patch implantation. The new cells were present both in the patch and in the adjacent damaged heart tissue.

The patched hearts also had greater development of new blood vessels, which appeared to have improved delivery of oxygen and nutrients to the tissue, thus reducing the number of cells that perished compared to unpatched hearts.

In addition to helping heart tissue regenerate, the patch could be used as a delivery system for getting medications or stem cells into a patient, Ruiz-Lozano said.

Daniel Bernstein, MD, professor of pediatric cardiology and a co-author of the paper, said the potential of the patch as a delivery system could make it useful in treating children with heart problems.

"For pediatric patients with congenital heart disease, or who have heart damage from a viral infection or other heart injury, we could use this to introduce growth factors directly to the heart in a way that would persist for a long period of time," he said.

Ruiz-Lozano and her colleagues are already at work on studies to explore the use of the patch as a delivery system, along with conducting studies of how the patch will perform in larger animals.


Story Source:

The above story is based on materials provided by Stanford University Medical Center. The original article was written by Louis Bergeron. Note: Materials may be edited for content and length.


Journal Reference:

  1. Vahid Serpooshan, Mingming Zhao, Scott A. Metzler, Ke Wei, Parisha B. Shah, Andrew Wang, Morteza Mahmoudi, Andrey V. Malkovskiy, Jayakumar Rajadas, Manish J. Butte, Daniel Bernstein, Pilar Ruiz-Lozano. The effect of bioengineered acellular collagen patch on cardiac remodeling and ventricular function post myocardial infarction. Biomaterials, 2013; DOI: 10.1016/j.biomaterials.2013.08.017

Cite This Page:

Stanford University Medical Center. "Collagen patch speeds repair of damaged heart tissue in mice." ScienceDaily. ScienceDaily, 29 August 2013. <www.sciencedaily.com/releases/2013/08/130829214605.htm>.
Stanford University Medical Center. (2013, August 29). Collagen patch speeds repair of damaged heart tissue in mice. ScienceDaily. Retrieved April 20, 2014 from www.sciencedaily.com/releases/2013/08/130829214605.htm
Stanford University Medical Center. "Collagen patch speeds repair of damaged heart tissue in mice." ScienceDaily. www.sciencedaily.com/releases/2013/08/130829214605.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