Background: Insulin resistance is a major pathophysiological feature of type 2 diabetes mellitus (T2DM), but the precise cellular mechanisms underlying impaired glucose uptake remain incompletely understood. Mitochondrial dysfunction and altered cellular energy (ATP) metabolism have been increasingly implicated in insulin resistance. This review explores the potential association between mitochondrial dysfunction, impaired ATP metabolism, increased basal sympathetic activity, and insulin resistance.

Methods: We reviewed published evidence to examine the relationship between impaired mitochondrial ATP production, increased basal sympathetic activity, and insulin resistance. We focused on the role of ATP-dependent insulin signaling, PI3K–AKT pathways, GLUT4 translocation, and sympathetic regulation of cellular energy demand. We also assessed the central concept of imbalance between cellular ATP availability and energy demand, which contributes to impaired insulin signaling and glucose utilization.

Results: GLUT4 transporters on the cell surface are necessary for facilitated diffusion of glucose from the extracellular fluid (ECF) into the intracellular fluid (ICF). This transport process does not directly require ATP; however, ATP is required to support insulin signaling and the cellular processes involved in GLUT4 translocation and P13k-AKT activation. Mitochondrial dysfunction can reduce ATP production, impair fatty acid oxidation, increase reactive oxygen species (ROS) generation, and alter mitochondrial dynamics. These alterations may contribute to impaired insulin signaling and insulin resistance. We propose that persistent sympathetic activation may increase cellular metabolic activity and ATP demand, potentially resulting in an ATP demand–supply mismatch. This mismatch may adversely affect insulin signaling and GLUT4 trafficking.

Conclusion: An association between impaired mitochondrial energy metabolism, ATP demand–supply mismatch, impaired GLUT4 translocation to the cell surface, increased basal sympathetic activity & insulin resistance has been suggested. Chronic psychological stress may contribute to sustained sympathetic activation. Further experimental and clinical studies are required to establish causality and to determine whether improving mitochondrial ATP availability or reducing sympathetic activity can enhance insulin sensitivity.