Identification of a functional missense variant in the matrix metallopeptidase 10 (MMP10) gene in two families with premature myocardial infarction

TL;DR

A genetic variant in the MMP10 gene is linked to early heart attacks and affects protein interactions and inflammation in macrophages.

Contribution

A novel functional missense variant in MMP10 is identified and shown to alter protein behavior and macrophage function in atherosclerosis.

Findings

The p.L245P variant in MMP10 reduces free binding energy and alters the substrate-binding cleft in MMP10-TIMP1 interactions.

Macrophages with the p.L245P variant show increased adhesion, reduced migration, and higher pro-inflammatory chemokine secretion.

The variant may contribute to atherosclerosis by promoting plaque rupture through altered macrophage behavior.

Abstract

A positive family history is a major independent risk factor for atherosclerosis, and genetic variation is an important aspect of cardiovascular disease research. We identified a heterozygous missense variant p.L245P in the MMP10 gene in two families with premature myocardial infarction using whole-exome sequencing. The aim of this study was to investigate the consequences of this variant using in-silico and functional in-vitro assays. Molecular dynamics simulations were used to analyze protein interactions, calculate free binding energy, and measure the volume of the substrate-binding cleft of MMP10-TIMP1 models. The p.L245P variant showed an altered protein surface, different intra- and intermolecular interactions of MMP10-TIMP1, a lower total free binding energy between MMP10-TIMP1, and a volume-minimized substrate-binding cleft of MMP10 compared to the wild-type. For the functional assays, human THP-1 cells were transfected with plasmids containing MMP10 cDNA carrying the p.L245P and wild-type variant and differentiated into macrophages. Macrophage adhesion and migration assays were then conducted, and pro-inflammatory chemokine levels were evaluated. The p.L245P variant led to macrophages that were more adherent, less migratory, and secreted higher levels of the pro-inflammatory chemokines CXCL1 and CXCL8 than wild-type macrophages. Thus, the p.L245P variant in MMP10 may influence the pathogenesis of atherosclerosis in families with premature myocardial infarction by altering protein - protein interactions, macrophage adhesion and migration, and expression of pro-inflammatory chemokines, which may increase plaque rupture. These results could contribute to the development of selective MMP10 inhibitors and reduce the risk of atherosclerosis in families with a history of premature myocardial infarction.

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