Red-emitting chemosensor detects superoxide anion in models of myocardial hypertrophy

Cardiac hypertrophy is a compensatory pathological alteration of the heart in response to prolonged stress, for which suitable diagnostic methods are lacking. Superoxide anion (O₂˙^-) levels are considered to be elevated during the progression of this disease. A red-emitting fluorescent chemosensor DO was rationally designed and synthesized. It enabled sensitive and accurate detection of O₂˙^- in solution, with a low limit of detection (LOD) of 93 nM. Chemosensor DO detected the increase in O₂˙^- concentration induced by angiotensin II (Ang II) in vitro and showed that losartan antagonizes Ang II-induced O₂˙^- production. Chemosensor DO was applied to detect elevated superoxide levels in heart tissue sections from hypertrophic mice. Therefore, this probe provides a new perspective for understanding the pathogenesis of cardiac hypertrophy.