Meanwhile, various proteases secreted by neutrophils serve as key tools for the clearance function: neutrophil elastase released in the early ischemic phase possesses the ability to degrade elastin [33, 34]; neutrophil-derived granule MMP-8 cleaves type I α1 and α2 chains, degrades collagen, and promotes neutrophil migration, while deficiency of MMP-8 reduces neutrophils and inhibits early collagen degradation [37]; moreover, overexpression of neutrophil-derived MMP-9 can inhibit ECM synthesis and attenuate inflammatory responses, thereby indirectly reducing myocardial fibrosis [38]. This evidence concerns the gene MMP8 and Myocardial fibrosis.