Bone morphogenetic protein 7 induces cementogenic differentiation of human periodontal ligament-derived mesenchymal stem cells

Abstract

Bone morphogenetic protein 7 (BMP-7) is a multifunctional differentiation factor that belongs to the transforming growth factor superfamily. BMP-7 induces gene expression of protein tyrosine phosphatase-like, member A/cementum attachment protein (PTPLA/CAP) and cementum protein 1 (CEMP1), both of which are markers of cementoblasts and cementocytes. In the previous study, we reported that BMP-7 treatment enhanced PTPLA/CAP and CEMP1 expression in both normal and immortal human periodontal ligament (PDL) cells. To elucidate the molecular mechanisms of the gene expression of these molecules, in this study, we identified a functional transcription activator binding region in the promoter region of PTPLA/CAP and CEMP1 that is responsive to BMP signals. Here, we report that some short motifs termed GC-rich Smad-binding elements (GC-SBEs) that are located in the human PTPLA/CAP promoter and CEMP1 promoter are BMP-7 responsive as analyzed with luciferase promoter assays. On the other hand, we found that transcription of Sp7/Osterix and PTPLA/CAP was up-regulated after 1 week of BMP-7 treatment on purified normal human PDL cells as a result of gene expression microarray analysis. Furthermore, transcription of Sp7/Osterix, runt-related transcription factor 2 (RUNX2), and alkaline phosphatase (ALP) was up-regulated after 2 weeks of BMP-7 treatment, whereas gene expression of osteo/odontogenic markers such as integrin-binding sialoprotein (IBSP), collagen, type I, alpha 1 (COL1A1), dentin matrix acidic phosphoprotein 1 (DMP1), and dentin sialophosphoprotein (DSPP) was not up-regulated in purified normal or immortal human PDL cells as a result of qRT-PCR. The results suggest that BMP-7 mediates cementogenesis via GC-SBEs in human PDL cells and that its molecular mechanism is different from that for osteo/odontogenesis.

Signaling Pathways in Dental Stem Cells During Their Maintenance and Differentiation

“…BMP7 treatment upregulates the transcription of Sp7/Osterix and PTPLA/CAP by binding to specifi c short motifs termed as GC-rich Smad-binding elements (GC-SBEs) located in the human PTPLA/CAP and CEMP1 promoter. The gene expression levels of RUNX2 and ALP are increased afterward while the expression of odontogenic markers such as DSPP, bone sialoprotein (BSP) and dentin matrix acidic phosphoprotein 1 (DMP1) are not affected [ 67 ].…”

Graphene-Based Nanomaterials for Tissue Engineering in the Dental Field

“…On the contrary, Osterix (OSX) and Osteocalcin (OCN), whose expressions are associated with late osteoblast differentiation stages, were found to be down-regulated on all the substrate preparations. Starting from this result, the authors explored the expression of two specific cementum-related genes, Cementum Attachment Protein (CAP) and Cementum Protein 1 (CEMP1), that are expressed at early and late differentiation stages, respectively [ 86 ]. All the scaffolds tested were associated with significant down-regulation of CAP and concomitant over-expression of CEMP1, suggesting that graphene-fibroin composites can induce cementoblast differentiation of the human PDLSCs in the absence of any growth factors.…”

Usefulness of Mesenchymal Cell Lines for Bone and Cartilage Regeneration Research

“…Positive for ARS (slightly reduced compared with primary cells) [90] and cementogenesis-related gene expression [31] Not tested Not tested CMSC29 Positive for ARS [91] Positive for ABS in pellet culture [91,92] Very weak positivity for OROS [91] DMSC23 Positive for ARS (increased compared with CMSC29) [91,93] Positive for ABS in pellet culture [91,92] Very weak positivity for OROS [91] CPC531 Positive for APS and upregulation of osteogenesis-related genes [95] Spontaneous chondrogenesis in 3D alginate culture, proved by upregulation of ColII and Sox9 and downregulation of Runx2 and ColI [95] Positive for OROS and upregulation of adipogenesis-related genes [95] Positive for ARS and VKS (increased compared with KP) [55], and also ALP activity [39] Positive for ABS [55] and ColII upregulation [56] in pellet culture Positive for OROS (reduced compared with KP) [55] hASCs-TE (same parental cells as hASCs-T)…”

“…Nowadays, a high number of MSC lines that display specific characteristics and differentiation capabilities have been generated and are valuable tools as part of models of disease and tissue repairing strategies. Different MSC lines have been employed for testing [17,[20][21][22][23][24][25] or producing [26,27] engineered scaffolds for skeletal applications, and for both investigating the MSC differentiation process [28][29][30][31][32][33][34] and finding new ways to improve it [35][36][37][38][39]. Additionally, these cell lines have also been used for analyzing functional makers [19,40] or even for exploring their roles in different diseases, such as osteoarthritis [41,42].…”