Study shows insulin-producing cells can regenerate
May. 5, 2004

(AP) - A new study shows that insulin-producing cells in the pancreas can regenerate themselves, suggesting future treatments for diabetes that could eliminate the need to inject the hormone.

In type 1, or juvenile, diabetes, the body's immune system attacks and destroys a type of specialized cell that makes insulin. The hormone is vital in maintaining the right blood sugar levels.

Regenerating and maintaining these cells in the pancreas could help people with type 1 diabetes make their own insulin. The research does not address the vast majority of diabetes cases, type 2, which are linked to obesity.

Researchers have been seeking ways to produce more of these specialized insulin-producing cells, called beta cells. The new study, done in laboratory mice, suggests there is no need to look beyond the cells themselves. Details are in Thursday's issue of the journal Nature.

Previous studies have suggested that embryonic stem cells or adult stem cells also could be sources for the insulin-producing cells.

The new research found no evidence that adult stem cells - which some groups have hoped would offer an alternative to human embryos - are involved in the regeneration of the insulin-producing cells.

"That's now been eliminated in my mind and gives us two cell types to concentrate on," said study co-author Douglas Melton, a Howard Hughes Medical Institute researcher at Harvard University.

Other experts disagreed, saying differently designed experiments could reveal that adult stem cells do play a role.

"We need to keep all the options open, absolutely," said Vijay Ramiya, who researches pancreatic beta cells at the University of Florida.

It also remains unclear whether beta cells could replicate themselves in sufficient numbers to be useful.

And coaxing embryonic stem cells into forming new insulin-producers appears difficult too, since the cells tend to form tumorous growths, said David Prentice of Indiana State University and a founder of Do No Harm, a group opposed to the use of embryonic stem cells.

Worldwide, there are about 171 million diabetics but only about 10 per cent of those have type 1 diabetes. The vast majority have type 2 diabetes, which is linked to obesity. In the United States, about 900,000 to 1.8 million people have type 1 diabetes, the American Diabetes Association says.