Gasdermin D inhibition confers antineutrophil mediated cardioprotection in acute myocardial infarction

Acute myocardial infarction (AMI) induces blood leukocytosis, which correlates inversely with patient survival. The molecular mechanisms leading to leukocytosis, and recruitment to the infarcted heart, remain poorly understood. Using an AMI mouse model, gasdermin D (GSDMD) was identified in activated neutrophils early in AMI. We demonstrated that GSDMD is required for enhanced recruitment of neutrophils and monocytes to the infarcted heart. Loss of GSDMD resulted in reduced release of IL-1β from neutrophils and reduced recruitment of neutrophils and monocytes to the infarcted heart. Knockout of GSDMD in mice significantly reduced infarct size, improved cardiac function and increased survival post AMI. Through a series of bone marrow transplantation studies and leukocytes depletion experiments, we further demonstrated that excessive bone marrow derived and GSDMD-dependent neutrophil recruitment, contributes to the detrimental immunopathology after AMI. Pharmacological inhibition of GSDMD also conferred cardioprotection post AMI, through reduction of scar size and enhancement of heart function. Our study provides new mechanistic insights into molecular regulation of neutrophil generation and recruitment after AMI, and supports GSDMD as a new target for improved ventricular remodeling and reduced heart failure after AMI. Heart mRNA profiles of 12 samples including post AMI (Day1), AMI (Day7) and Sham