Researchers in Belgium have significantly advanced the discovery of a pancreatic progenitor cell with the capacity to generate new insulin-producing beta cells. If the finding made in mice holds for humans, the newfound progenitor cells may represent “an obvious target for therapeutic regeneration of beta cells in diabetes,” the researchers report in the Jan. 25 issue of Cell, a publication of Cell Press. In people with type 1 diabetes, blood sugar rises due to a loss of the insulin-producing pancreatic beta cells. Insulin is a hormone that helps the body use glucose for energy.
“One of the most interesting characteristics of these [adult] progenitor cells is that they are almost indistinguishable from embryonic progenitor cells,” said Harry Heimberg at the Juvenile Diabetes Research Foundation Center at Vrije Universiteit Brussel in Belgium and the Beta Cell Biology Consortium. “In terms of their structure and gene expression, there are no major differences. They look and behave just like embryonic beta cell progenitors.”
Previous studies have suggested the existence of a beta cell progenitor in the pancreas after birth, but the identification and characterization of the progenitor cell has not been fully achieved. Other studies showing that replication of adult beta cells can account for beta cell turnover and expansion of beta cells under normal physiologic conditions and called into question the role or existence of a progenitor cell in regeneration. “Most people gave up looking because the cells are so few and so hard to activate,” added Heimberg.
In the new study, Heimberg’s team tied off a duct that drains digestive enzymes from the pancreas, a manipulation that led to a doubling of beta cell mass in the injured part of the pancreas within two weeks. The animals’ pancreases also began producing more insulin, evidence that the new beta cells were fully functional. Using a genetic labeling technique, the researchers found that the new beta cells were derived from precursor cells that expressed a gene expressed in embryonic progenitor cells called Neurogenin 3 (Ngn3) and that production of the new beta cells depended on activity of this gene. He suspects the regenerative process is sparked by an inflammatory response in the enzyme-flooded pancreas.
Release date: January 25, 2008
Source: Juvenile Diabetes Research Foundation International
Filed Under: Drug Discovery