2021 Volume 13 Issue 2 Pages 41-48
Nucleotide-binding oligomerization domain 2 (NOD2), which is constitutively expressed in human pulp fibroblasts, plays a role in pulpal immune responses by sensing muramyl dipeptide (MDP) from bacteria, which leads to pulpitis. Matrix metalloproteinase-3 (MMP-3), which exhibits broad substrate specificity to the extracellular matrix (ECM) and induces angiogenesis and fibroblast wound healing, is expressed when pulp is inflamed. In the present study, we examined MDP/NOD2-induced MMP-3 production and the role of its signaling cascade involving TAK1/MAP kinase in human deciduous dental pulp fibroblast-like cells (hDDPFs). MDP did not affect the proliferation or viability of hDDPFs. The MAP kinase signaling pathway was involved in the production of MMP-3 in MDP-stimulated hDDPFs. The MDP stimulation enhanced ERK 1/2 phosphorylation, but did not affect the degradation of IκB. These results suggest that the production of MMP-3 in MDP-stimulated hDDPFs stimulated the degradation of surrounding collagen, leading to alterations in the structure of the ECM and inflammation, and appeared to promote angiogenesis.
