Direct dapagliflozin exposure enhances respiration and membrane hyperpolarization in isolated cardiac mitochondria

Dapagliflozin, a sodium–glucose cotransporter 2 (SGLT2) inhibitor widely used for the treatment of diabetes, has been consistently associated with cardiovascular protection, including attenuation of ischemia/reperfusion injury and reduced incidence of heart failure. However, the cellular and molecular mechanisms underlying these effects remain incompletely understood. In this context, the present study aimed to investigate whether dapagliflozin exerts direct effects on mitochondrial function and bioenergetics. Cardiac mitochondria were isolated from Wistar rats (Rattus norvegicus), and mitochondrial function was systematically evaluated by assessing oxygen consumption, ATP production, reactive oxygen species (ROS) generation, and mitochondrial membrane potential following exposure to dapagliflozin (10 nM). Dapagliflozin increased oxygen consumption in states 1–3 supported by complex I substrates and enhanced both basal and ADP-stimulated respiration in complex II, without affecting state 4 respiration, complex IV activity, or maximal uncoupled respiration. In parallel, dapagliflozin significantly reduced mitochondrial ROS production in both complexes I and II without altering ATP generation, resulting in an increased ATP/ROS ratio, indicative of improved bioenergetic efficiency. Notably, electron leakage was increased in complex I but remained unchanged in complex II, suggesting differential modulation of electron transport chain components. Furthermore, dapagliflozin induced mitochondrial membrane hyperpolarization in the presence of Ca2+, with or without oligomycin, and to a lesser extent in the presence of K⁺, while no significant effects were observed under Na⁺ conditions. Collectively, these findings demonstrate that dapagliflozin directly modulates mitochondrial bioenergetics and redox balance, supporting a mechanistic link between mitochondrial function and its cardioprotective effects.