The Critical Role of MMP13 in Regulating Tooth Development and Reactionary Dentinogenesis Repair Through the Wnt Signaling Pathway

Abstract

Matrix-metalloproteinase-13 (MMP13) is important for bone formation and remodeling; however, its role in tooth development remains unknown. To investigate this, MMP13-knockout (Mmp13−/−) mice were used to analyze phenotypic changes in the dentin–pulp complex, mineralization-associated marker-expression, and mechanistic interactions. Immunohistochemistry demonstrated high MMP13-expression in pulp-tissue, ameloblasts, odontoblasts, and dentin in developing WT-molars, which reduced in adults, with human-DPC cultures demonstrating a >2000-fold increase in Mmp13-expression during mineralization. Morphologically, Mmp13−/− molars displayed critical alterations in the dentin-phenotype, affecting dentin-tubule regularity, the odontoblast-palisade and predentin-definition with significantly reduced dentin volume (∼30% incisor; 13% molar), and enamel and dentin mineral-density. Reactionary-tertiary-dentin in response to injury was reduced at Mmp13−/− molar cusp-tips but with significantly more dystrophic pulpal mineralization in MMP13-null samples. Odontoblast differentiation-markers, nestin and DSP, reduced in expression after MMP13-loss in vivo, with reduced calcium deposition in MMP13-null DPC cultures. RNA-sequencing analysis of WT and Mmp13−/− pulp highlighted 5,020 transcripts to have significantly >2.0-fold change, with pathway-analysis indicating downregulation of the Wnt-signaling pathway, supported by reduced in vivo expression of the Wnt-responsive gene Axin2. Mmp13 interaction with Axin2 could be partly responsible for the loss of odontoblastic activity and alteration to the tooth phenotype and volume which is evident in this study. Overall, our novel findings indicate MMP13 as critical for tooth development and mineralization processes, highlighting mechanistic interaction with the Wnt-signaling pathway.

Self-Assembling Peptides with Insulin-Like Growth Factor Mimicry

“…The quantitative results from every assay were obtained using image analyzing software NIH ImageJ. 49 Binding Kinetics Assay. The affinity of the different peptides to the receptor was determined with microscale thermophoresis (MST), using a red Tris-NTA dye (NanoTemper GmBH, Catalog #MO-L011) to label recombinant VEGFR2 domains 1−7 (Acrobiosystems, Catalog #KDR-H5227).…”

“…#7074) at room temperature for 1 h, developed by incubating the membrane for 5 min at room temperature with a chemiluminescent substrate (SuperSignal West Pico PLUS, Thermo Fisher) and then detected using an Azure 600 imaging system (Azure Biosystems). The quantitative results from every assay were obtained using image analyzing software NIH ImageJ …”

The odontoblastic differentiation of dental mesenchymal stem cells: molecular regulation mechanism and related genetic syndromes

“…Stathmin can enhance the odontogenetic differentiation of hDPSCs via Wnt/β-catenin pathway ( Zhang et al, 2019 ). Matrix-metalloproteinase-13 (MMP-13) interacts with Wnt/β-catenin pathway, as in MMP13 -knockout mice, the Wnt-responsive gene Axin2 was downregulated and dentin formation was defected ( Duncan et al, 2022 ). Herbal extracts also promote odontoblast differentiation of DPSCs via Wnt/β-catenin pathway, such as Berberine, Baicalein, and Wedelolactone ( Lee et al, 2016 ; Wang et al, 2018 ; Wu et al, 2019 ).…”

The Reparative Function of MMP13 in Tertiary Reactionary Dentinogenesis after Tooth Injury

“…The current work focuses on a specific matrix metalloproteinase (MMP (MMP13)) that belongs to a family of host-derived, zinc-dependent endopeptidases [18] that degrade and reorganize extracellular matrix components [19], which we have recently shown to have critical functions in dentine-pulp tissues [20]. Furthermore, MMPs orchestrate multiple important dental tissue processes, including angiogenesis, differentiation, and chemotaxis [21,22].…”

“…Furthermore, MMPs orchestrate multiple important dental tissue processes, including angiogenesis, differentiation, and chemotaxis [21,22]. Several in vitro and in vivo studies have investigated the influence of selected MMPs on enamel [23] and dentine formation [20], as well as the regulation of pulpitis [24][25][26]. The deletion of specific MMPs has resulted in an altered dentine structure in MMP9-knockout (KO) mice [16] and critical alterations to dentine after MMP13-KO in developing teeth, as shown by our research team [20].…”