Abstract
In this paper, mathematical modeling of
nonlinear dynamics of blood hormones regulatory system, which includes glucose,
insulin and glucagon hormones and with the presence of the secreted insulin due
to the pancreatic beta cells, is developed and investigated. This model
considers the time evolution of nonlinear dynamics of the equations for the
blood hormones that represent glucose, glucagon and insulin concentrations plus
insulin and glucagon actions as well as secreted insulin due to the pancreatic
beta cells. Using both theoretical and numerical procedures, we determine such
quantities by examining some data for the case of one patient at three different
times of the day as well as the case of three patients at the same time of the
day and for different values of the parameters. We find that the nonlinear
effects due to the time-dependent interactions between these hormones can be
notable and affect the resulting values for each hormone for given instant in
time. For the present nonlinear dynamical system, there are parameters whose
values differ for different diabetes patients and their roles to determine the
values of the glucose, glucagon and insulin concentrations in the patient’s
blood and the responses that arise due to the insulin and glucagon actions can
be notable. We find, in particular, that the cases with relatively moderate or
smaller values of the parameters, which represent kinetics of the insulin
action, insulin sensitivity, rate for the glucagon action and the glucagon
sensitivity, can lead to moderate or smaller values of the plasma glucose
concentration.
Keywords: Blood glucose,
Glucose dynamics, Blood hormones.