Navigation Links
Scientists find a new way insulin-producing cells die

SAN ANTONIO, Texas, U.S.A. (Feb. 25, 2011) The death of insulin-producing beta cells in the pancreas is a core defect in diabetes. Scientists in Italy and Texas now have discovered a new way that these cells die by toxic imbalance of a molecule secreted by other pancreatic cells.

"Our study shows that neighboring cells called alpha cells can behave like adversaries for beta cells. This was an unexpected finding," said Franco Folli, M.D., Ph.D., professor of medicine/diabetes at The University of Texas Health Science Center at San Antonio. He is co-lead author on the study with Carla Perego, Ph.D., assistant professor of physiology at the University of Milan.

Balance needed to control sugars

Alpha and beta cells are grouped in areas of the pancreas called the islets of Langerhans. Alpha cells make glucagon, the hormone that raises blood sugar during fasting. In the same environment the beta cells make insulin, the hormone that lowers sugars after a meal. Imbalance ultimately leads to diabetes.

"We found that glutamate, a major signaling molecule in the brain and pancreas, is secreted together with glucagon by alpha cells and affects beta cell integrity," Dr. Folli said. "In a situation where there is an imbalance toward more alpha cells and fewer beta cells, as in Type 1 and Type 2 diabetes, this could result in further beta cell destruction."

Role of alpha cells

Glutamate toxicity is a new mechanism of beta cell destruction not previously known, Drs. Perego and Folli said. It has not been typically thought that alpha cells could themselves be a cause of beta cell damage, they said.

The study also found a protection for beta cells, namely, a protein called GLT1 that controls glutamate levels outside the beta cells. "GLT1 is like a thermostat controlling the microenvironment of beta cells with respect to glutamate concentration," Dr. Perego said.

Early warning

A diagnostic test for glutamate toxicity in the islets of Langerhans is being developed by the authors, Dr. Folli said. Eventually an intervention to slow the process could follow.

Glutamate poisoning is a new candidate mechanism for beta cell destruction in diabetes. Others are high glucose, buildup of a protein called amyloid, and free fatty acids, which are found in patients with type 2 diabetes.

"The vicious cycle in diabetes is that there are several substances that have been shown, also by us, to be toxic to beta cells," Dr. Folli said. "And now we have found a new one, glutamate."


Contact: Will Sansom
University of Texas Health Science Center at San Antonio

Related biology news :

1. TCD scientists discover that self-eating cells safeguard against cancer
2. MIT scientists say ocean currents cause microbes to filter light
3. Even in a crowd, you remain unique, UCLA life scientists report
4. Gender gap: Selection bias snubs scholarly achievements of female scientists
5. Brown scientists to discuss best practices for the oceans
6. Scientists discover agaves tremendous potential as new bioenergy feedstock
7. University of Miami scientists find new way to estimate global rainfall and track ocean pollution
8. Scientists discover cell of origin for childhood muscle cancer
9. Choosing your neighbors: MBL scientists see how microbes relate in space
10. Hershey scientists improve methods for analysis of healthful cocoa compounds
11. UCR scientists to explore new genetic tools in mosquito research: Transposable elements
Post Your Comments:
(Date:11/17/2015)... 17, 2015 Paris ... --> Paris , qui s,est ... DERMALOG, le leader de l,innovation biométrique, a inventé le ... et empreintes sur la même surface de balayage. Jusqu,ici, ... l,autre pour les empreintes digitales. Désormais, un seul scanner ...
(Date:11/12/2015)... Nov. 12, 2015  Arxspan has entered into ... and Harvard for use of its ArxLab cloud-based ... tools. The partnership will support the institute,s efforts ... chemical research information internally and with external collaborators. ... for managing the Institute,s electronic laboratory notebook, compound ...
(Date:11/9/2015)... Nov. 09, 2015 ... of the "Global Law Enforcement Biometrics ... --> ) has announced ... Enforcement Biometrics Market 2015-2019" report to ... Markets ( ) has announced the ...
Breaking Biology News(10 mins):
(Date:11/30/2015)... , Nov. 30, 2015 Harvard ... ), a biotechnology company developing bioengineered organ implants ... written notification from The NASDAQ Stock Market that ... price requirements. The letter noted that as a ... common stock having exceeded $1.00 per share for ...
(Date:11/30/2015)... , Nov. 30, 2015 Spherix Incorporated ... committed to the fostering and monetization of intellectual ... and prospective initiatives designed to create shareholder value. ... Officer of Spherix. "Based on published reports, the ... exceeds $50 billion and Spherix will seek to ...
(Date:11/30/2015)... Nov. 30, 2015  Champions Oncology, Inc. (CSBR), engaged ... to personalize the development and use of oncology drugs, ... Officer, will be presenting at the LD MICRO Investor ... Standard Time (PST).  The conference, held at the Luxe ... CA , will feature 200 small/micro-cap companies and ...
(Date:11/30/2015)... TapImmune, Inc. (TPIV), a ... peptide and gene-based immunotherapeutics and vaccines for the treatment ... be presenting at the 8 th Annual LD ... PM PT. Dr. John N. Bonfiglio a ... the presentation and will join TapImmune management in meeting ...
Breaking Biology Technology: