In Vitro Interactions Between Insulin-Producing ?? Cells and Embryonic Dorsal Root Ganglia

Abstract

It has been suggested that the autoimmune assault in type 1 diabetes is not restricted to islet beta cells but also encompasses intraislet nervous structures. Thus, in addition to modulating islet endocrine function, the nerves may also play a direct pathogenic role in diabetes. A major problem in determining the role of neurons in islet function is to distinguish specific neural effects from those mediated through the vascular system, extrinsic hormones, and/or nutritional factors. The aim of this study was to develop an in vitro system that will enable studies on communication between 1 particular type of neuron and islet cell. To achieve this, we cocultured rat islets and rat embryonic dorsal root ganglia (DRG) in a 3-dimensional roller-tube system for 1 to 4 weeks. We found a distinct glucose-induced insulin response throughout the culture period. This response was lower compared with islets cultured alone. DRGs survived better when they were cocultured with islet cells. The roller-tube coculture system provides a novel in vitro system for exploring the interaction between different subpopulations of neurons and pancreatic beta cells. Coculture with DRG neurons reduced glucose-induced insulin release from beta cells, indicating that sensory nerve activity inhibits the insulin response.