Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A loofah for the heart?

21.07.2005


If you’ve ever used a loofah in the shower, you’ve stirred up some stem cells. As the outer layer skin of sloughs off, stem cells in the dermis rush to repair and replace those buffed away.



Now imagine a tiny loofah that works in much the same way inside the corridors of the human heart. As it scrubs, it alerts heart stem cells to rush to the site of dying cells to begin renewal and repair of cardiomyocytes - cells that pump blood through the heart.

While a heart loofah may remain the stuff of medical fantasy, Steven Houser, Ph.D., Director of Cardiovascular Center for Temple University School of Medicine and Senior Associate Dean of Research, is sold on the idea that the heart - like the skin - contains its own stem cells: cells that are self-renewing and can be differentiated into different types of heart tissue. It’s a controversial subject in cardiovascular circles, but for Houser, who spent thirty years studying the molecular biology of heart cells, the stakes are worth it when it comes to combating congestive heart failure (CHF).


CHF, which afflicts 4.8 million Americans, occurs when the heart no longer has the strength to pump blood efficiently, resulting in an increasingly diminished quality of life. While a wide variety of well-understood conditions such as high blood pressure or excess weight can lead to CHF, a cure for the debilitating disease is less clear. Invasive surgical procedures such as a bypass operation or the insertion of a stent can extend a patient’s life, but the essential damage to the heart caused by the condition remains. Pharmacological therapies to improve the function of cardiac muscle cells improve heart function, but the treatments often lead to fatal arrhythmias, canceling out any benefits. To Houser, the problem proved frustrating.

"Cells were dying in the heart and there were simply not enough new cells to replace them," he says. "They were tired soldiers who could no longer work efficiently, and there were no new soldiers coming to take their place."

Although stem cells have been found in many other organs in the body, including the brain, many cardiac researchers remain unconvinced that the heart contains stem cells. For one, stem cells can over multiply and cause tumors, and the heart rarely gets tumors. These facts and the observations that adult cardiac myocytes do not have the capacity to proliferate have led most investigators to accept the dogma that no new cardiac myocytes are manufactured in the normal heart.

Houser respectfully disagrees. Abandoning his prior cell research, he joined forces with one of the foremost investigators in cardiac stem cells, Pierro Anversa, Ph.D. professor of medicine and Director of the Cardiovascular Institute at the New York Medical College at Valhalla, New York. Anversa, who has been on the forefront of stem cell research for the past five years, has suggested that heart cells undergo an ongoing turnover fueled by cardiac stem cells. In June of this year, Anversa published a study that actually identified cardiac stem cells in animal models that repaired tissue damaged by a heart attack.

One element that convinced Houser of Anversa’s work was his own research into how the heart reacts under the stress of hypertensive diseases that can lead to congestive heart failure. Early in the disease, the heart muscle mass increases and the chambers stretch in a vain attempt to increase contracting power. While part of the enlargement is due to increased muscle mass, the question of how the chambers grow is less certain.

The traditional view holds that cardiac cells simply grow larger to accommodate the increased need, but Houser and Anversa developed a different theory - that spurred by the cardiac stem cells, cardiomyocytes actually increase in number in their response to the heart’s traumatic condition.

"It was striking that with hypertension there were actually more cardiomyocytes than were originally lost," says Houser. "New myocytes were forming in excess of the cells that were dying."

And if that were true, these were the new soldiers to replace those missing in action.

To test this theory, Houser, with the help of Anversa, has received a new NIH grant to study if there are autologous stem cells in the heart. The two researchers have arrived at a deceptively simple idea. After inducing hypertension in an animal model to produce a distressed heart they will study the heart tissue and count cells, first in the normal heart and then in a heart that must work harder to develop excess pressure. If, according to the scientists’ thesis, there are more cardiomyocytes in the heart as opposed to simply larger cells, they will conclude that stem cells had a hand in an attempt to repair and restore the heart.

If their hunch proves correct, the implications for treatment of heart disease are profound. In the future, for example, Houser envisions people banking their own stem cells, so that when a problem arises, new tissue can be made by injecting these cells into the damaged heart. The idea is simple, use the patients own cardiac stem cells to repair their damaged heart.

"We’ve made a tremendous impact on cardiovascular diseases such as congestive heart failure through the hard work of physicians, better service, stents and bypasses," he says. "But what we need to do now is to reverse this disease rather than just slow its progression."

Although his colleagues may remain skeptical, Houser has committed himself to the stem cell model. Inducing cells to promote repair can answer the question that has haunted his career.

"We don’t know how to fix the broken heart, but stem cells might be a large part of the answer."

Eryn Jelesiewicz | EurekAlert!
Further information:
http://www.temple.edu

More articles from Life Sciences:

nachricht Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View
22.06.2018 | University of Sussex

nachricht New cellular pathway helps explain how inflammation leads to artery disease
22.06.2018 | Cedars-Sinai Medical Center

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Graphene assembled film shows higher thermal conductivity than graphite film

22.06.2018 | Materials Sciences

Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle

22.06.2018 | Earth Sciences

Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View

22.06.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>