The serine proteinase hepsin is an activator of pro-matrix metalloproteinases: molecular mechanisms and implications for extracellular matrix turnover

• Published in: Scientific reports Vol. 7; no. 1; pp. 16693 - 13
• Main Authors: Wilkinson, David J., Desilets, Antoine, Lin, Hua, Charlton, Sarah, del Carmen Arques, Maria, Falconer, Adrian, Bullock, Craig, Hsu, Yu-Chen, Birchall, Kristian, Hawkins, Alastair, Thompson, Paul, Ferrell, William R., Lockhart, John, Plevin, Robin, Zhang, Yadan, Blain, Emma, Lin, Shu-Wha, Leduc, Richard, Milner, Jennifer M., Rowan, Andrew D.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-12-2017; Nature Publishing Group
• Subjects: 631/337/474; 631/45/468; 82/51; Aggrecan; Aggrecans - metabolism; Animals; Cartilage diseases; Cartilage, Articular - cytology; Cartilage, Articular - metabolism; Cattle; Cells, Cultured; Collagen; Collagen - metabolism; Core protein; Extracellular matrix; Extracellular Matrix - metabolism; Humanities and Social Sciences; Humans; Inflammation; Matrix Metalloproteinase 1 - chemistry; Matrix Metalloproteinase 1 - metabolism; Matrix Metalloproteinase 3 - chemistry; Matrix Metalloproteinase 3 - metabolism; Mice; Mice, Inbred C57BL; Molecular Dynamics Simulation; Molecular modelling; multidisciplinary; Osteoarthritis; Osteoarthritis - metabolism; Osteoarthritis - pathology; Protein Structure, Tertiary; Proteinase; Proteolysis; Receptor, PAR-2 - metabolism; Science; Science (multidisciplinary); Serine; Serine Endopeptidases - chemistry; Serine Endopeptidases - metabolism; Serine proteinase; Synovitis; Synovitis - pathology; Tumor necrosis factor; Tumor Necrosis Factor-alpha - metabolism; Tumors
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-017-17028-3

Increasing evidence implicates serine proteinases in the proteolytic cascades leading to the pathological destruction of extracellular matrices such as cartilage in osteoarthritis (OA). We have previously demonstrated that the type II transmembrane serine proteinase (TTSP) matriptase acts as a novel initiator of cartilage destruction via the induction and activation of matrix metalloproteinases (MMPs). Hepsin is another TTSP expressed in OA cartilage such that we hypothesized this proteinase may also contribute to matrix turnover. Herein, we demonstrate that addition of hepsin to OA cartilage in explant culture induced significant collagen and aggrecan release and activated proMMP-1 and proMMP-3. Furthermore, hepsin directly cleaved the aggrecan core protein at a novel cleavage site within the interglobular domain. Hepsin expression correlated with synovitis as well as tumour necrosis factor α expression, and was induced in cartilage by a pro-inflammatory stimulus. However, a major difference compared to matriptase was that hepsin demonstrated markedly reduced capacity to activate proteinase-activated receptor-2. Overall, our data suggest that hepsin, like matriptase, induces potent destruction of the extracellular matrix whilst displaying distinct efficiencies for the cleavage of specific substrates.