From The New York Times:
For years, researchers have investigated how the body loses the ability to produce enough insulin, a hallmark of diabetes. Now an intriguing theory is emerging, and it suggests a potential treatment that few scientists had considered. The hormone insulin helps shuttle glucose, or blood sugar, from the bloodstream into individual cells to be used as energy. But the body can become resistant to insulin, and the beta cells of the pancreas, which produce the hormone, must work harder to compensate. Eventually, the thinking goes, they lose the ability to keep up. “We used to say that the beta cells poop out,” said Alan Saltiel, director of the Life Sciences Institute at the University of Michigan. In reality, he added, this shorthand meant “we have no idea what’s going on.” Some evidence suggested that large numbers of these cells died through a process of programmed cell death called apoptosis. But that was at best a partial explanation. Now, researchers at Columbia University have put forth a surprising alternative. In mice with Type 2 diabetes, the researchers showed that beta cells that had lost function were not dead at all. Most remained alive, but in a changed form. They reverted to an earlier developmental, “progenitor,” state. It’s as if these cells are “stepping back in time to a point where they look like they might have looked during their development,” said Dr. Domenico Accili, director of the Columbia University Diabetes and Endocrinology Research Center, who led the new work.
…A range of physiological stresses, including obesity, pregnancy and aging, all tend to increase demand on beta cells to produce more insulin, Dr. Accili said. It may be that they are “taking a little rest,” he said, in returning to a less active state. Although it’s not yet clear why this might happen, the finding may lend support to the view that doctors should focus on relieving stress on the beta cells rather than pushing them to produce more insulin, which may speed the progression of diabetes, Dr. Accili said.