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:4/28/2016)... BANGALORE, India , April 28, 2016 ... subsidiary of Infosys (NYSE: INFY ), and Samsung ... global partnership that will provide end customers with a ... and payment services.      (Logo: ... for financial services, but it also plays a fundamental part ...
(Date:4/19/2016)... -- The new GEZE SecuLogic access control ... system solution for all door components. It can be ... interface with integration authorization management system, and thus fulfills ... dimensions of the access control and the optimum integration ... considerable freedom of design with regard to the doors. ...
(Date:4/13/2016)... 13, 2016  IMPOWER physicians supporting Medicaid patients in ... new clinical standard in telehealth thanks to a new ... higi platform, IMPOWER patients can routinely track key health ... mass index, and, when they opt in, share them ... to a local retail location at no cost. By ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... June 23, 2016 Houston Methodist Willowbrook ... Cy-Fair Sports Association to serve as their official ... Houston Methodist Willowbrook will provide sponsorship support, athletic ... with association coaches, volunteers, athletes and families. ... Cy-Fair Sports Association and to bring Houston Methodist ...
(Date:6/23/2016)... --  EpiBiome , a precision microbiome engineering company, today ... from Silicon Valley Bank (SVB). The financing will allow ... drug development efforts, as well as purchase additional lab ... been an incredible strategic partner to us – one ... provide," said Dr. Aeron Tynes Hammack , EpiBiome,s ...
(Date:6/23/2016)... Ky. , June 23, 2016 ... two Phase 1 clinical trials of its complement ... placebo-controlled, single and multiple ascending dose studies designed ... pharmacodynamics (PD) of subcutaneous injection in healthy adult ... subcutaneously (SC) either as a single dose (ranging ...
(Date:6/23/2016)... ... June 23, 2016 , ... ClinCapture, the ... Convention Center and will showcase its product’s latest features from June 26 to ... a scientific poster on Disrupting Clinical Trials in The Cloud during the conference. ...
Breaking Biology Technology: