{'fraction_non_alphanumeric': 0.02643573381950775, 'fraction_numerical': 0.005013673655423883, 'mean_word_length': 5.513353115727003, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Epilysin (matrix metalloproteinase-28) joins the matrix metalloproteinase team on the field of postmyocardial infarction remodeling.

Although significant advancements in the treatment of acute coronary syndromes have occurred, myocardial injury culminating in a myocardial infarction (MI) remains a significant and problematic outcome. The initial cellular and extracellular events that occur soon after an MI are those fairly prototypical to a wound-healing response, characterized by a robust expression of a number of inflammatory mediators, inflammatory cells, and eventually the emergence of a fibroblast phenotype, the myofibroblast. However, a divergence in this prototypical wound response occurs at later post-MI time periods. Notably, rather than a well-formed quiescent scar, continued extracellular matrix (ECM) turnover and instability can occur, ultimately yielding a process of infarct expansion and left ventricular (LV) dilation. Indeed, the magnitude of this post-MI LV dilation, presumably secondary to infarct expansion and matrix instability, is a recognized determinant of clinical outcomes.1,2 The post-MI period is one characterized by a number of complex events that are both time and cell type dependent, and these events are likely relevant to both the MI region and the viable myocardium, in terms of post-MI remodeling. Of particular interest and potential therapeutic relevance are biological cascades that contribute to the instability of the ECM in the post-MI context. In this issue of Circulation Research ,3 Ma and colleagues identify how a specific proteolytic pathway can significantly alter critical signaling and cell-dependent events within the ECM, and in turn, alter the course of post-MI remodeling.

Article, see p 675 

The initial description of a matrix-degrading enzyme was based on the seminal observations, whereby the excised tadpole tail degraded a collagen gel—hence the term collagenase.4 Over 23 matrix metalloproteinase (MMP) types are expressed in humans, and the distribution, functionality, and substrates are diverse. The MMPs were classified based on recognized substrates, and although this nomenclature no longer holds relevance …