Matrix Metalloproteinase-3 in Odontoblastic Cells Derived from Ips Cells: Unique Proliferation Response as Odontoblastic Cells Derived from ES Cells

Abstract

We previously reported that matrix metalloproteinase (MMP)-3 accelerates wound healing following dental pulp injury. In addition, we reported that a proinflammatory cytokine mixture (tumor necrosis factor-α, interleukin (IL)-1β and interferon-γ) induced MMP-3 activity in odontoblast-like cells derived from mouse embryonic stem (ES) cells, suggesting that MMP-3 plays a potential unique physiological role in wound healing and regeneration of dental pulp in odontoblast-like cells. In this study, we tested the hypothesis that upregulation of MMP-3 activity by IL-1β promotes proliferation and apoptosis of purified odontoblast-like cells derived from induced pluripotent stem (iPS) and ES cells. Each odontoblast-like cell was isolated and incubated with different concentrations of IL-1β. MMP-3 mRNA and protein expression were assessed using RT-PCR and western blotting, respectively. MMP-3 activity was measured using immunoprecipitation and a fluorescence substrate. Cell proliferation and apoptosis were determined using ELISA for BrdU and DNA fragmentation, respectively. siRNA was used to reduce MMP-3 transcripts in these cells. Treatment with IL-1β increased MMP-3 mRNA and protein levels, and MMP-3 activity in odontoblast-like cells. Cell proliferation was found to markedly increase with no changes in apoptosis. Endogenous tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 were constitutively expressed during all experiments. The exocytosis inhibitor, Exo1, potently suppressed the appearance of MMP-3 in the conditioned medium. Treatment with siRNA against MMP-3 suppressed an IL-1β-induced increase in MMP-3 expression and activity, and also suppressed cell proliferation, but unexpectedly increased apoptosis in these cells (P<0.05). Exogenous MMP-3 was found to induce cell proliferation in odontoblast-like cells derived from iPS cells and ES cells. This siRNA-mediated increase in apoptosis could be reversed with exogenous MMP-3 stimulation (P<0.05). Taken together, IL-1β induced MMP-3-regulated cell proliferation and suppressed apoptosis in odontoblast-like cells derived from iPS and ES cells.

Retraction: Products of dentin matrix protein-1 degradation by interleukin-1β-induced matrix metalloproteinase-3 promote proliferation of odontoblastic cells

“…Conversely, the control siRNA had no such effect ( Figure 5A). Silencing the MMP-3 gene also significantly decreased IL-1β-stimulated cell proliferation (p < 0.01; Figure 5A) as described previously (9,10). Taken together, these data suggest that IL-1β-induced DMP-1 expression depends on the expression of MMP-3 in odontoblast-like cells.…”

“…Notably, treatment with IL-1β induces potent expression of MMP-3 in dental pulp, a tissue that contains large numbers of odontoblasts (7). We also reported that proinflammatory cytokine IL-1β-induced MMP-3 activity is associated with cell proliferation of purified odontoblast-like cells derived from mouse embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) (9,10). Thus, IL-1β-induced MMP-3 appears to be pivotal in the pathophysiology of inflamed dental pulp containing rich odontoblasts.…”

“…Because performing experiments using purified odontoblast-like cells derived from mouse iPSCs (11) and ESCs (12), we have developed excellent in vitro models in which to examine the mechanisms of wound healing following exposure to proinflammatory cytokines (9,10). We have also previously reported that a proinflammatory cytokine mixture of IL-1β, tumor necrosis factor-α, and interferon-γ, or IL-1β alone, can induce MMP-3 activity in rat dental pulp cells, and result in a potent increase in cell proliferation (13,14).…”

Retraction：Polyphosphate-induced matrix metalloproteinase-3-mediated differentiation in rat dental pulp fibroblast-like cells

“…MMP-3 synthesis is tightly controlled in vivo (13,15). Our previous study reported that proinflammatory cytokine-induced MMP-3 actually accelerates wound healing following dental pulp injury (16)(17)(18) and promotes cell proliferation (17,19,20).…”

Retraction: Polyphosphate-induced matrix metalloproteinase-3-mediated proliferation in rat dental pulp fibroblast-like cells is mediated by a Wnt5 signaling cascade

“…Synthesis of MMP-3 is tightly controlled in vivo (12,14). Although it is intuitive that dental pulp destruction may be a function of MMPs, our previous study showed that proinflammatory cytokine-induced MMP-3 actually accelerates wound healing following dental pulp injury (15)(16)(17) and promotes cell proliferation of odontoblasts derived from mouse induced pluripotent stem (iPS) cells and embryonic stem (ES) cells (16,18,19).…”