INS and type 1 diabetes mellitus: This model was successively expanded to describe other aspects of glucose homeostasis, including: a more detailed representation of the dependence of glucose utilization on glucose concentration, glucagon secretion and kinetics and its effects on glucose production, in type 1 diabetic patients (Dalla Man et al., 2014); circadian variations in insulin sensitivity [derived from Visentin et al. (2015)]; the “dawn” phenomenon (early-morning increase in blood glucose concentration) (Visentin et al., 2018); and a three-compartment model of insulin kinetics (Visentin et al., 2020).