Cellular markers of aging could reveal how insulin-producing cells begin to fail in type 2 diabetes
Diabetes researchers have puzzled for decades about why insulin-producing beta cells in one pancreatic islet often look and behave quite differently than their counterparts in the same islet or in nearby islets. Using newly identified cellular markers of aging, Joslin Diabetes Center scientists now have shown that this diversity may be driven at least in part by differently aged beta cell populations within the pancreas.
Additionally, the Joslin team demonstrated that the aging of beta cells, with associated losses of their insulin secretion, can be accelerated by insulin resistance, a condition that can lead toward type 2 diabetes.
"This research opens up an entirely new set of questions about the development of type 2 diabetes," says Susan Bonner-Weir, a Joslin Senior Investigator and corresponding author on a paper describing the work in the journal Cell Metabolism. The disease worsens over time as beta cells die off or perform less effectively, for reasons that are not well understood.
Scientists have long known that beta cells change significantly over time, says Bonner-Weir, who is also Professor of Medicine at Harvard Medical School (HMS). Back in 2011, for example, her lab demonstrated that beta cells in newborn rats are immature cells with very different gene expression and function than adult beta cells.
Her lab's most recent work, led by HMS Instructor Cristina Aguayo-Mazzucato, started instead with very old mice, created for another experiment, whose beta cells emitted fluorescent signals. The investigators could compare the insulin-producing beta cells from the Continue reading