Article

Tenascin-C promotes differentiation of rat dental pulp cells in vitro.

Oral Health Science Center HRC7, Tokyo Dental College, Chiba, Tokyo; and, Japan; Department of Clinical Pathophysiology, Tokyo Dental College, Chiba, Japan.
International Endodontic Journal (Impact Factor: 2.05). 06/2012; DOI: 10.1111/j.1365-2591.2012.02089.x
Source: PubMed

ABSTRACT AIM: To investigate the effects of tenascin-C (TN-C) on cultured rat dental pulp cells in relation to the expression of Notch signalling. METHODOLOGY: Subcultured dental pulp cells derived from rat incisors were seeded both in wells and on plastic coverslips coated with various concentrations of recombinant human TN-C. Expression of bone-related mRNA was then analysed by RT-PCR and observed by immunohistochemical staining. Encoding of Notch1 and Notch2 (markers of initial differentiation of odontoblast-like cells), alkaline phosphatase (ALP), osteopontin (OPN) and osteocalcin (OCN) (markers of mineralization) was investigated. Non-TN-C-coated wells were used as controls. Primary antibodies to Notch1, ALP and OCN were used for immunofluorescence staining, and ALP activity was evaluated. Data were compared using Student's t-test. RESULTS: Cell proliferation rate in the experimental groups was significantly higher (P < 0.05) than that in the control group at 72 h. Expression of Notch1, Notch2, ALP, OPN and OCN mRNAs was significantly higher (P < 0.05) in the experimental group than that in the control group. Strongly positive staining for Notch1, ALP and OCN was observed in the experimental group. ALP activity was significantly higher (P < 0.01) in the experimental group than in the control group at 24 h. CONCLUSION: TN-C promoted differentiation of rat dental pulp cells by the activation of Notch.

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