ß-Cell Heterogeneity and Plasticity.

ABSTRACT

The existence of functionally diverse and plastic ß cells in islets of Langerhans has been reported since the 1980s. Recently, high-resolution technologies have advanced our understanding of ß-cell heterogeneity and plasticity. Here, we define plasticity broadly as dynamic changes in cellular phenotypes and heterogeneity as differences in cellular behaviors. Individual ß cells react differently to environmental challenges and act together to maintain ß-cell mass and glucose homeostasis within a narrow range of 70-140 mg/dL. During the progress of diabetes, this elaborate balance is disrupted, and a lack of ß-cell compensation leads to dysregulated blood glucose. In this chapter, we assess ß-cell stress that instigates increased ß-cell heterogeneity and adaptive ß-cell responses such as proliferation, dedifferentiation, maturity, and insulin secretion. We also discuss the maturity, electrical activity, and insulin secretion of well-characterized ß-cell subgroups. Finally, we touch upon the plasticity of other non-ß pancreatic cells and their cooperation with ß cells to maintain homeostasis.