Expression of Matrix Metalloproteinases during Rat Skin Wound Healing: Evidence that Membrane Type-1 Matrix Metalloproteinase Is a Stromal Activator of Pro-Gelatinase A

Abstract

Skin wound healing depends on cell migration and extracellular matrix remodeling. Both processes, which are necessary for reepithelization and restoration of the underlying connective tissue, are believed to involve the action of extracellular proteinases. We screened cDNA libraries and we found that six matrix metalloproteinase genes were highly expressed during rat skin wound healing. They were namely those of stromelysin 1, stromelysin 3, collagenase 3, gelatinase A (GelA), gelatinase B, and membrane type-1 matrix metalloproteinase (MT1-MMP). The expression kinetics of these MMP genes, the tissue distribution of their transcripts, the results of cotransfection experiments in COS-1 cells, and zymographic analyses performed using microdissected rat wound tissues support the possibility that during cutaneous wound healing pro-GelA and pro-gelatinase B are activated by MT1-MMP and stromelysin 1, respectively. Since MT1-MMP has been demonstrated to be a membrane-associated protein (Sato, H., T. Takino, Y. Okada, J. Cao, A. Shinagawa, E. Yamamoto, and M. Seiki. 1994. Nature (Lond.). 370: 61–65), our finding that GelA and MT1-MMP transcripts were expressed in stromal cells exhibiting a similar tissue distribution suggests that MT1-MMP activates pro-GelA at the stromal cell surface. This possibility is further supported by our observation that the processing of proGelA to its mature form correlated to the detection of MT1-MMP in cell membranes of rat fibroblasts expressing the MT1-MMP and GelA genes. These observations, together with the detection of high levels of the mature GelA form in the granulation tissue but not in the regenerating epidermis, suggest that MT1-MMP and GelA contribute to the restoration of connective tissue during rat skin wound healing.

Matrix Metalloproteinase 10 Degradomics in Keratinocytes and Epidermal Tissue Identifies Bioactive Substrates With Pleiotropic Functions*

“…Interestingly, MMP10 released fragments of the same sizes from recombinant CYR61 as MMP14 (71). The latter is expressed by stromal cells upon wounding (72) and might modulate CYR61 activities in the granulation tissue, whereas our results suggest that MMP10 leads to similar cleavages in the epidermis.…”

17β-Estradiol Inhibits Wound Healing in Male Mice via Estrogen Receptor-α

“…25 We found MT1-MMP also to be strongly expressed by the neoepidermis in day 3 wounds (Figure 5E). Subsequent immunoblot analysis revealed overall wound MT1-MMP levels to be comparable between estrogen-treated and control mice ( Figure 5F), although neoepidermal MT1-MMP levels were significantly increased as a consequence of estrogen treatment ( Figure 5G).…”

Amplification of IL-1β-Induced Matrix Metalloproteinase-9 Expression by Superoxide in Rat Glomerular Mesangial Cells Is Mediated by Increased Activities of NF-κB and Activating Protein-1 and Involves Activation of the Mitogen-Activated Protein Kinase Pathways

“…1B). In vivo the conversion from the latent to the active enzymes is executed by the actions of soluble proteases, most prominently tissue plasminogen activator and the membranebound collagenase MT1-MMP (39,40). However, under cell culture conditions these proteases may either not be present or may be adequately active to convert high levels of the latent enzyme.…”