Membrane-Mediated Determinants of NSAID-Induced Cardiotoxicity Independent of Cyclooxygenase Selectivity

Background and Purpose: Non-steroidal anti-inflammatory drugs (NSAIDs) exhibit differential profiles of toxicity that extend beyond cyclooxygenase (COX) inhibition. This study characterised the mechanistic basis of NSAID-associated tissue and cardiac effects by integrating systemic, developmental, and molecular outcomes. Experimental Approach: Ketoprofen, Indomethacin, and Celecoxib were evaluated in adult rat models using serum biomarkers and histopathology; cardiac rhythm assessment was performed in zebrafish embryos; in vitro methods included cardiac-mimicking lipid membranes supplemented with calorimetry, NMR spectroscopy, and molecular dynamics simulations. Key Results: Ketoprofen produced the most pronounced elevations in circulating markers of injury and histological evidence of tissue stress, whereas indomethacin showed minor histopathological changes with minimal systemic disturbance. Celecoxib caused limited adult tissue injury but had a significant impact on zebrafish heart rate. Biophysical analyses revealed distinct drug–lipid interaction modes: celecoxib destabilised membrane organisation, ketoprofen promoted bilayer ordering and condensation, and indomethacin demonstrated weaker interfacial interactions. Thermodynamic signatures and molecular simulations were concordant with these biophysical effects. Conclusions and Implications: NSAID toxicity profiles are context-specific and mechanistically heterogeneous. Differential interaction with cardiac-relevant membranes appears to underlie variations in functional cardiac outcomes, linking molecular behaviour to organism-level physiology. These data emphasise the utility of combining conventional toxicological assessments with lipid biophysics to elucidate off-target effects of NSAIDs.