Influence of Glucose on Cardiac Pacemaking Electrophysiology through Potassium Ion Channel Biophysics: A Computational Study

High blood sugar levels (Hyperglycemia) are closely linked to a higher risk of unexpected cardiac arrest and fatal cardiac events, especially in people with diabetes. Although significant research has been conducted, the precise mechanisms underlying this relationship remain elusive, and this calls for further investigation into the impact of glucose homeostasis on myocardial electrical activity. This research implies that glucose-detection pathways in heart tissue may play a role in this relationship. To delve into this, we customized a computational model simulating the human pacemaker action potential by integrating glucose-responsive pathways and their engagements with voltage-gated potassium ion channels examined using ordinary differential equations. The model's variable values were derived from previously conducted experimental data, and computational research, allowing us to simulate how glucose levels impact the firing of action potentials in the sinoatrial node. Investigations leveraging voltage clamp and current clamp techniques suggested that higher glucose levels reduce potassium ionic currents, decreasing the frequency of pacemaker action potentials. Ultimately, our mathematical model provides insights into how elevated glucose levels could contribute to bradycardia and enhance susceptibility to sudden cardiac death at the cellular scale.