Multiscale modelling of insulin secretion during an intravenous glucose tolerance test

Dysfunctional insulin secretion from pancreatic beta-cells plays a major role in the development of diabetes. The intravenous glucose tolerance test (IVGTT) is a widely used clinical test to assess beta-cell function. The analysis of IVGTT data is conveniently performed using mathematical models, which need to be fairly simple to enable parameter identifiability (minimal models), but should at the same time have sound biological foundation at the cellular level. Using mathematical analysis and model reduction, we show here that our recent mathematical model of insulin secretory granule dynamics in beta-cells provides mechanistic underpinning for our minimal model of pancreatic insulin secretion during an IVGTT.