A ROS-responsive, self-immolative and self-reporting hydrogen sulfide donor with multiple biological activities for the treatment of myocardial infarction

Myocardial infarction (MI), as one of the leading causes of global death, urgently needs effective therapies. Recently, hydrogen sulfide (H(2)S) has been regarded as a promising therapeutic agent for MI, while its spatiotemporally controlled delivery remains a major issue limiting clinical translation. To address this limitation, we designed and synthesized a novel H(2)S donor (HSD-R) that can produce H(2)S and emit fluorescence in response to reactive oxygen species (ROS) highly expressed at diseased sites. HSD-R can specifically target mitochondria and provide red fluorescence to visualize and quantify H(2)S release in vitro and in vivo. Therapeutically, HSD-R significantly promoted the reconstruction of cardiac structure and function in a rat MI model. Mechanistically, myocardial protection is achieved by reducing cardiomyocyte apoptosis, attenuating local inflammation, and promoting angiogenesis. Furthermore, inhibition of typical pro-apoptotic genes (Bid, Apaf-1, and p53) played an important role in the anti-apoptotic effect of HSD-R to achieve cardioprotection, which were identified as new therapeutic targets of H(2)S against myocardial ischemia injury. This ROS-responsive, self-immolative, and fluorescent H(2)S donor can serve as a new theranostic agent for MI and other ischemic diseases.