Necrostatin-1 alleviates reperfusion injury following acute myocardial infarction in pigs.

Background: In rodents, it has previously been shown that necrostatin-1 (Nec-1) inhibits RIP1, a central regulator of programmed necrosis, thereby decreasing cell death and reducing infarct size (IS) after ischaemia/reperfusion (I/R) injury. To address unanswered questions on feasibility and efficacy of Nec-1 in a large animal model, we assessed the effects of Nec-1 in a porcine I/R model, relevant to human disease.

Materials And Methods: In Dalland landrace pigs (69 ± 3 kg), I/R injury was induced by a 75-min surgical ligation of the left circumflex coronary artery (LCx). Ten minutes prior to reperfusion, pigs were randomly allocated to different Nec-1 doses (1.0 mg/kg or 3.3 mg/kg) or vehicle treatment (control, CTRL). Functional endpoints and immunohistological analyses were performed 24 h after reperfusion.

Results: Nec-1 3.3 mg/kg significantly reduced IS (n = 6; 24.4 ± 15.6%) compared to Nec-1 1.0 mg/kg (n = 5; 54.8 ± 16.9%) or CTRLs (n = 6; 62.1 ± 26.6%; P = 0.016). In line, LV ejection fraction (LVEF) was significantly higher in Nec-1 3.3 mg/kg, copared to Nec-1 1.0 mg/kg or CTRL treated animals (50.0 ± 12.0% vs. 32.5 ± 12.9% vs. 31.9 ± 6.6%, respectively, P = 0.015). Hemodynamically, a preserved contractility was observed [end-systolic volume at 100 mmHg (ESV100 )] at 24-h follow-up (87.6 ± 17.3 mL vs. 74.5 ± 41.1 mL vs. 56.8 ± 11.8 mL, respectively, P = 0.032), reflecting improved cardiac function.

Conclusions: In the pig model of I/R injury, intravenous administration of Nec-1 prior to reperfusion was an effective and above all practical therapeutic strategy that significantly reduced IS and preserved left ventricular function. These data highlight the potential of cardioprotection as a promising adjuvant therapy in the setting of early reperfusion following I/R injury.