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 Diabetes mellitus: A risk factor for early colorectal cancer
27.05.2020 | Nationales Centrum für Tumorerkrankungen (NCT) Heidelberg

nachricht Ultra-thin fibres designed to protect nerves after brain surgery
27.05.2020 | Martin-Luther-Universität Halle-Wittenberg

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: Biotechnology: Triggered by light, a novel way to switch on an enzyme

In living cells, enzymes drive biochemical metabolic processes enabling reactions to take place efficiently. It is this very ability which allows them to be used as catalysts in biotechnology, for example to create chemical products such as pharmaceutics. Researchers now identified an enzyme that, when illuminated with blue light, becomes catalytically active and initiates a reaction that was previously unknown in enzymatics. The study was published in "Nature Communications".

Enzymes: they are the central drivers for biochemical metabolic processes in every living cell, enabling reactions to take place efficiently. It is this very...

Im Focus: New double-contrast technique picks up small tumors on MRI

Early detection of tumors is extremely important in treating cancer. A new technique developed by researchers at the University of California, Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from normal tissue. The work is published May 25 in the journal Nature Nanotechnology.

researchers at the University of California, Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from...

Im Focus: I-call - When microimplants communicate with each other / Innovation driver digitization - "Smart Health“

Microelectronics as a key technology enables numerous innovations in the field of intelligent medical technology. The Fraunhofer Institute for Biomedical Engineering IBMT coordinates the BMBF cooperative project "I-call" realizing the first electronic system for ultrasound-based, safe and interference-resistant data transmission between implants in the human body.

When microelectronic systems are used for medical applications, they have to meet high requirements in terms of biocompatibility, reliability, energy...

Im Focus: When predictions of theoretical chemists become reality

Thomas Heine, Professor of Theoretical Chemistry at TU Dresden, together with his team, first predicted a topological 2D polymer in 2019. Only one year later, an international team led by Italian researchers was able to synthesize these materials and experimentally prove their topological properties. For the renowned journal Nature Materials, this was the occasion to invite Thomas Heine to a News and Views article, which was published this week. Under the title "Making 2D Topological Polymers a reality" Prof. Heine describes how his theory became a reality.

Ultrathin materials are extremely interesting as building blocks for next generation nano electronic devices, as it is much easier to make circuits and other...

Im Focus: Rolling into the deep

Scientists took a leukocyte as the blueprint and developed a microrobot that has the size, shape and moving capabilities of a white blood cell. Simulating a blood vessel in a laboratory setting, they succeeded in magnetically navigating the ball-shaped microroller through this dynamic and dense environment. The drug-delivery vehicle withstood the simulated blood flow, pushing the developments in targeted drug delivery a step further: inside the body, there is no better access route to all tissues and organs than the circulatory system. A robot that could actually travel through this finely woven web would revolutionize the minimally-invasive treatment of illnesses.

A team of scientists from the Max Planck Institute for Intelligent Systems (MPI-IS) in Stuttgart invented a tiny microrobot that resembles a white blood cell...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Dresden Nexus Conference 2020: Same Time, Virtual Format, Registration Opened

19.05.2020 | Event News

Aachen Machine Tool Colloquium AWK'21 will take place on June 10 and 11, 2021

07.04.2020 | Event News

International Coral Reef Symposium in Bremen Postponed by a Year

06.04.2020 | Event News

 
Latest News

Black nitrogen: Bayreuth researchers discover new high-pressure material and solve a puzzle of the periodic table

29.05.2020 | Materials Sciences

Argonne researchers create active material out of microscopic spinning particles

29.05.2020 | Materials Sciences

Smart windows that self-illuminate on rainy days

29.05.2020 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>