July 26, 2002

MGH scientists have discovered that a naturally occurring hormone can cause adult islet stem cells to mature into pancreatic beta cells, the insulin-secreting cells that are depleted or compromised in diabetes. The results, which appear in the August issue of Endocrinology, could help researchers design a strategy for reversing the disease. "These findings are important because, in diabetes, beta cells in the pancreas have a limited capacity to proliferate, and they die at a steady rate," says Joel Habener, MD, (at left) of the MGH Laboratory of Molecular Endocrinology, the paper's senior author.

Type 1 diabetes is caused by destruction of insulin-producing beta cells of the pancreas in a mistaken attack by the body's immune system. In type 2 diabetes, the most common form of the disease, patients' beta cells do not produce enough insulin at the right time and overall metabolism does not respond correctly to insulin. For both types of diabetes, finding new ways to provide functioning beta cells has been an area of great interest for researchers. Previous research has shown that an intestinal hormone called GLP-1 can provoke beta cells to proliferate and to secrete insulin. Habener and his team now provide evidence that the hormone may also cause islet stem cells – originally identified by the researchers in a 2001 study – to mature into true beta cells, which may lead to new strategies for treating diabetes.

"If we can transplant beta cells grown from a patient's own stem cells, the risk of rejection is gone," says Habener. "And now with the addition of GLP-1, we might be able to stimulate those cells to become truly functional." The other members of the research team are Elizabeth Abraham, PhD; Colin Leech, PhD; Julia Lin; and Henryk Zulewski, PhD.