Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Gene therapy promising for preventing restenosis

17.09.2002


An experimental gene transfer technique shut down cell re-growth in the arteries’ interior lining and reduced the inflammatory response – two main causes of re-narrowing of newly opened blood vessels, researchers report in today’s rapid access issue of Circulation: Journal of the American Heart Association.



The process that opens blocked blood vessels – either inflating a tiny balloon to force open the narrowed vessel (angioplasty) or inserting a tiny mesh tube called a stent to serve as a scaffold to widen the opening – can damage the delicate lining of blood vessels, says Seppo Yla-Herttuala, M.D., Ph.D., professor of molecular medicine at the University of Kuoppio, Finland.

"This damage – rather than a progression of heart disease – is believed to cause rapid growth of new cells in the vessel wall, which can cause re-blockage, or restenosis, in the vessel," he says.


Earlier studies suggested that a key player in this process is a biological reaction called oxidative stress. When the endothelium – the blood vessel lining – is damaged, it sends a signal that increases oxidative stress, which means that the body produces more free radicals. The oxygen derivatives known as free radicals are very active chemical compounds "that can destroy almost anything," he says.

One of the most common of these compounds is the superoxide anion, a free radical that increases when the endothelium is damaged. At the same time, endothelial damage causes a decrease in concentrations of vascular superoxide dismutase or SOD, an enzyme that works inside and outside cells as a powerful antioxidant to control levels of free radicals. Yla-Herttuala and his colleagues theorized that by injecting the gene for extra cellular superoxide dismutase (EC-SOD) into damaged blood vessels, they could control free radical damage and thereby short-circuit the process that leads to restenosis.

In the study they tested this hypothesis by using a deactivated virus to deliver EC-SOD to cells in the arterial walls of animals. Researchers treated 18 New Zealand white rabbits with the gene and 18 with placebo. The animals were analyzed two and four weeks later to determine if the gene therapy had worked. At each follow-up the researchers confirmed that the gene transfer was successful.

At two weeks the EC-SOD group had 10-fold fewer macrophages (markers of inflammation) than the control group and 20-fold less macrophage accumulation at four weeks. Moreover, there was a significant reduction in superoxide anion production in the active gene transfer group, he says.

"EC-SOD has already been purified and commercially produced. The virus that we used has been similarly tested, so we expect that it will only take about two years to complete pre-clinical studies before we can begin human trials," Yla-Herttuala says.

In human studies, EC-SOD would be transferred "after a stent is placed and it would be delivered in the stented area and in the areas immediately outside the stent. The study demonstrates that the enzyme is also secreted by the cells after transfer so that it affects both the immediate site of transfer and the areas within a few centimeters of that site."

Co-authors were Mikko O. Laukkanen, Ph.D.; Antti Kivelä, M.D.; Tuomas Rissanen, B.M.; Juha Rutanen, B.M.; Minna K. Karkkainen, M.Sc.; Olli Leppanen, M.D.; and Jan Hinrich Brasen, M.D., Ph.D.

Carole Bullock | EurekAlert!
Further information:
http://www.americanheart.org/

More articles from Health and Medicine:

nachricht Microgel powder fights infection and helps wounds heal
14.11.2018 | Michigan Technological University

nachricht Spread of deadly eye cancer halted in cells and animals
13.11.2018 | Johns Hopkins Medicine

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Putting food-safety detection in the hands of consumers

15.11.2018 | Information Technology

Insect Antibiotic Provides New Way to Eliminate Bacteria

15.11.2018 | Life Sciences

New findings help to better calculate the oceans’ contribution to climate regulation

15.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>