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 One gene closer to regenerative therapy for muscular disorders
01.06.2017 | Cincinnati Children's Hospital Medical Center

nachricht The gut microbiota plays a key role in treatment with classic diabetes medication
01.06.2017 | University of Gothenburg

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: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>