u-0126 and tricalcium-silicate

Biodentine (Septodont, Saint-Maur-des-Fossès, France), a new tricalcium silicate cement formulation, has been introduced as a bioactive dentine substitute to be used in direct contact with pulp tissue. The aim of this study was to investigate the response of human dental pulp stem cells (hDPSCs) to the material and whether mitogen-activated protein kinase (MAPK), nuclear factor-kappa B (NF-κB), and calcium-/calmodulin-dependent protein kinase II (CaMKII) signal pathways played a regulatory role in Biodentine-induced odontoblast differentiation.. hDPCs obtained from impacted third molars were incubated with Biodentine. Odontoblastic differentiation was evaluated by alkaline phosphatase activity, alizarin red staining, and quantitative real-time reverse-transcriptase polymerase chain reaction for the analysis of messenger RNA expression of the following differentiation gene markers: osteocalcin (OCN), dentin sialophosprotein (DSPP), dentin matrix protein 1 (DMP1), and bone sialoprotein (BSP). Cell cultures in the presence of Biodentine were exposed to specific inhibitors of MAPK (U0126, SB203580, and SP600125), NF-κB (pyrrolidine dithiocarbamate), and CaMKII (KN-93) pathways to evaluate the regulatory effect on the expression of these markers and mineralization assay.. Biodentine significantly increased alkaline phosphatase activity and mineralized nodule formation and the expression of OCN, DSPP, DMP1, and BSP. The MAPK inhibitor for extracellular signal-regulated kinase 1/2 (U0126) and Jun N-terminal kinase (SP600125) significantly decreased the Biodentine-induced mineralized differentiation of hDPSCs and OCN, DSPP, DMP1, and BSP messenger RNA expression, whereas p38 MAPK inhibitors (SB203580) had no effect. The CaMKII inhibitor KN-93 significantly attenuated and the NF-κB inhibitor pyrrolidine dithiocarbamate further enhanced the up-regulation of Biodentine-induced gene expression and mineralization.. Biodentine is a bioactive and biocompatible material capable of inducing odontoblast differentiation of hDPSCs. Our results indicate that this induction is regulated via MAPK and CaMKII pathways.

Topics: Adolescent; Adult; Alkaline Phosphatase; Anthracenes; Benzylamines; Butadienes; Calcium Compounds; Calcium-Calmodulin-Dependent Protein Kinase Type 2; Cell Culture Techniques; Cell Differentiation; Dental Pulp; Extracellular Matrix Proteins; Humans; Imidazoles; Integrin-Binding Sialoprotein; MAP Kinase Signaling System; NF-kappa B; Nitriles; Odontoblasts; Osteocalcin; Phosphoproteins; Protein Kinase Inhibitors; Pulp Capping and Pulpectomy Agents; Pyridines; Pyrrolidines; Sialoglycoproteins; Signal Transduction; Silicates; Stem Cells; Sulfonamides; Thiocarbamates; Young Adult

The aim of this study was to investigate the role of the extracellular signal-regulated kinase 1/2 (ERK1/2) pathway in regulating tricalcium silicate (C3S)-driven proliferation and biomineralization of human dental pulp cells (hDPCs) in vitro.. Human DPCs were cultured in C3S-containing medium and compared with untreated controls. Cell viability was measured by the methyl-thiazol-tetrazolium assay. Biomineralization was assessed by staining calcium deposits on the extracellular matrix with von Kossa and alizarin red S stains. Phosphorylated ERK1/2 was evaluated by immunoblotting. The ERK1/2 inhibitor U0126 was used to assess the role of this pathway on stage of the cell cycle and mineralization-dependent gene expressions of hDPCs by using flow cytometry and real-time polymerase chain reaction, respectively. Data were analyzed by analysis of variance followed by the Student-Newman-Keuls post hoc test, with significance set at P < .05.. The viability and biomineralization of hDPCs were promoted by C3S extracts (P < .05). Phosphorylated ERK1/2 strongly appeared after hDPCs were cultured in the C3S extracts for 30 minutes. Moreover, inhibition of the ERK1/2 pathway in C3S-treated hDPCs decreased proliferation and the expression of mineralization-dependent genes, including collagen type I, dentin sialophosphoprotein, osteopontin, and osteocalcin (P < .05).. C3S stimulated the proliferation and biomineralization of hDPCs in vitro, with the ERK1/2 pathway playing a key role in the regulation of these effects.

Topics: Adolescent; Butadienes; Calcium; Calcium Compounds; Cell Culture Techniques; Cell Proliferation; Cell Survival; Cells, Cultured; Collagen Type I; Dental Pulp; Enzyme Inhibitors; Extracellular Matrix; Extracellular Matrix Proteins; Extracellular Signal-Regulated MAP Kinases; Humans; MAP Kinase Signaling System; Nitriles; Osteocalcin; Osteopontin; Phosphoproteins; Pulp Capping and Pulpectomy Agents; Sialoglycoproteins; Silicates; Tooth Calcification; Young Adult