Therapeutic Inhibition of Acid-Sensing Ion Channel 1a Recovers Heart Function After Ischemia-Reperfusion Injury

Redd MA, Scheuer SE, Saez NJ, Yoshikawa Y, Chiu HS, Gao L, Hicks M, Villanueva JE, Joshi Y, Chow CY, Cuellar-Partida G, Peart JN, See Hoe LE, Chen X, Sun Y, Suen JY, Hatch RJ, Rollo B, Xia D, Alzubaidi MAH, Maljevic S, Quaife-Ryan GA, Hudson JE, Porrello ER, White MY, Cordwell SJ, Fraser JF, Petrou S, Reichelt ME, Thomas WG, King GF, Macdonald PS, Palpant NJ. Circulation DOI 10.1161/CIRCULATIONAHA.121.054360

Background: Ischemia-reperfusion injury (IRI) is one of the major risk factors implicated in morbidity and mortality associated with cardiovascular disease. During cardiac ischemia, the buildup of acidic metabolites results in decreased intracellular and extracellular pH, which can reach as low as 6.0 to 6.5. The resulting tissue acidosis exacerbates ischemic injury and significantly affects cardiac function. METHODS: We used genetic and pharmacologic methods to investigate the role of acid-sensing ion channel 1a (ASIC1a) in cardiac IRI at the cellular and whole-organ level. Human induced pluripotent stem cell-derived cardiomyocytes as well as ex vivo and in vivo models of IRI were used to test the efficacy of ASIC1a inhibitors as pre- and postconditioning therapeutic agents. RESULTS: Analysis of human complex trait genetics indicates that variants in the ASIC1 genetic locus are significantly associated with cardiac and cerebrovascular ischemic injuries. Using human induced pluripotent stem cell-derived cardiomyocytes in vitro and murine ex vivo heart models, we demonstrate that genetic ablation of ASIC1a improves cardiomyocyte viability after acute IRI.