Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Antioxidant Protects Islet Cells Used in Transplants for Diabetes

26.07.2002

A synthetic antioxidant developed by researchers at National Jewish Medical and Research Center improves the survival of islet cells used in transplants for diabetes. The findings, reported in the August issue of the journal Diabetes by researchers at the University of Pittsburgh, could help overcome a significant drawback of the "Edmonton Protocol," a promising treatment for diabetes.

"The antioxidant neutralizes the harmful free radicals generated when islet cells are isolated from the pancreas," said senior author Jon Piganelli, Ph.D., assistant professor of Pediatrics at the Diabetes Institute, Children’s Hospital of Pittsburgh, and the University of Pittsburgh School of Medicine. "More of the islet cells survived in culture. And when we transplanted islet cells into diabetic, immunodeficient mice, it took fewer of the antioxidant-treated islet cells to normalize their blood sugar."

In type 1 diabetes, a person’s immune system mistakenly attacks and destroys islet cells that secrete insulin necessary for the metabolism of sugar. Many diabetes patients take insulin shots to make up for the lost islet cells. In 2000, researchers from Edmonton, Alberta, reported new techniques that have made islet-cell transplantation a promising option for patients with type 1 diabetes. It allows patients to produce their own insulin. Patients have to take immunosuppressive drugs to prevent rejection of the transplants, but they maintain better control of their insulin levels, thus reducing the chances of future complications. They also avoid the daily insulin injections. Clinical trials of the "Edmonton protocol" are being conducted at several medical centers around the nation.

One drawback to the Edmonton protocol is that pancreata from at least two donors are needed to supply enough islet cells for one successful transplant. Many cells die during isolation and shortly after transplantation. Since islet cells also rapidly die in culture, surgeons are forced to transplant the cells immediately after they have been isolated. This prevents physicians from taking several steps that could improve the likelihood of a successful transplant. Isolation of the islet cells from the pancreas stresses them, leading to inflammation and islet-cell death. Highly reactive free-radical molecules contribute to this stress. Dr. Piganelli and his colleagues reasoned that an antioxidant compound might help islet cells survive and improve transplant success by neutralizing the free radicals.

The researchers used two synthetic antioxidants developed several years earlier by Dr. James Crapo, M.D., Chairman of the Department of Medicine at National Jewish, and his colleagues. The antioxidants, dubbed AEOL10113 and AEOL10150, mimic the naturally occurring antioxidant superoxide dismutase, but are effective against a wider range of oxygen radicals and last longer in the body. Now licensed by Incara Pharmaceuticals Corporation, they have shown promise in preventing damage to cells caused by stroke and radiation therapy for cancer. Earlier this year, Dr. Piganelli and his colleagues showed that the antioxidants could prevent the development of type 1 diabetes in mice when given T cells that normally causes the disease. (Press release)

"We are excited that these synthetic antioxidants are protecting cells in such a wide range of hazardous conditions," said Dr. Crapo.

Islet-cell loss was cut in half over a six-day period, from 60% to 30%, when the antioxidants were applied during isolation of the islet cells. The antioxidants also improved the effectiveness of the islet-cell transplants. When large amounts of islet cells (700-1,000 islet equivalents) were transplanted into six diabetic mice, all the animals became healthy. But when smaller amounts of islet cells (200-220 islet equivalents) were transplanted into nine diabetic mice, half the mice who got untreated islet cells remained diabetic while all the animals with antioxidant-treated islet cells returned to full health.

"The antioxidant-treated cells are healthier when they are transplanted into the mice and survive better after the transplant," said Dr. Piganelli. "We think it may be worthwhile to use the antioxidant during preservation of the pancreas, before the isolation begins, and after transplantation."

William Allstetter | EurekAlert
Further information:
http://www.dean-med.pitt.edu/home.asp
http://www.nationaljewish.org/faculty/crapo.html
http://www.incara.com/

More articles from Health and Medicine:

nachricht The genes are not to blame
20.07.2018 | Technische Universität München

nachricht Targeting headaches and tumors with nano-submarines
20.07.2018 | Universitätsmedizin der Johannes Gutenberg-Universität Mainz

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: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>