The NLRP3 Inflammasome Inhibitor, OLT1177 (Dapansutrile), Reduces Infarct Size and Preserves Contractile Function After Ischemia Reperfusion Injury in the Mouse

<jats:sec> <jats:title>Background:</jats:title> <jats:p>Activation of the NLRP3 inflammasome is a primary driver of sterile inflammation in response to myocardial ischemia reperfusion. Pharmacologic inhibitors of the NLRP3 inflammasome are being developed. We proposed that OLT1177 (dapansutrile), a novel NLRP3 inflammasome inhibitor, could preserve myocardial function after ischemia reperfusion injury in the mouse.</jats:p> </jats:sec> <jats:sec> <jats:title>Methods:</jats:title> <jats:p>We used an experimental murine model of myocardial ischemia reperfusion injury through transient ligation of the left coronary artery and measured the effects of OLT1177 (6, 60, or 600 mg/kg intraperitoneal dose) on infarct size at pathology and on systolic cardiac function at echocardiography. To simulate a clinical scenario, we investigated the time window of therapeutic intervention with OLT1177 (60 mg/kg) administered 60, 120, or 180 minutes after reperfusion.</jats:p> </jats:sec> <jats:sec> <jats:title>Results:</jats:title> <jats:p>OLT1177 was rapidly detectable in the plasma following intraperitoneal injection and had no effect on cardiac function in healthy mice. OLT1177 treatment at reperfusion showed significant dose-dependent reduction in infarct size (−36%, −67%, and −62% for 6, 60, and 600 mg/kg, respectively; <jats:italic toggle="yes">P</jats:italic> < 0.001 for linear trend, <jats:italic toggle="yes">P</jats:italic> = 0.010 vs. vehicle for 6 mg/kg, and <jats:italic toggle="yes">P</jats:italic> < 0.001 vs. vehicle for 60 and 600 mg/kg) and preserved cardiac systolic function measured as left ventricular fractional shortening at 24 hours and 7 days after injury (<jats:italic toggle="yes">P</jats:italic> = 0.015 for 6 mg/kg and <jats:italic toggle="yes">P</jats:italic> < 0.01 for 60 and 600 mg/kg). OLT1177 reduced infarct size also when given after 60 minutes of reperfusion (−71%, <jats:italic toggle="yes">P</jats:italic> < 0.001 vs. vehicle).</jats:p> </jats:sec> <jats:sec> <jats:title>Conclusion:</jats:title> <jats:p>OLT1177 (dapansutrile) limits infarct size and prevents left ventricular systolic dysfunction when given within 60 minutes following ischemia reperfusion injury in the mouse.</jats:p> </jats:sec>