Role of NFIC on cAMP-mediated diferentiation of stem cells from the apical papilla / 安徽医科大学学报

Objective To investigate the role of NFIC on the stimulation effects of cAMP-induced differentiation of stem cells from the apical papilla ( SCAPs) in vitro. Methods SCAPs isolated from dental papilla of human imma-ture third molars were cultured by enzyme digestion. SCAPs were transfected with lentivirus that overexpressed NF-IC gene ( ov-NFIC) or an empty vector ( LV-empty) and co-treatment with Forskolin. Mineralized nodule formation of each group was measured by alizarin red staining. Quantitative real-time reverse-transcription polymerase chain reaction was performed to test the expressions of RUNX2,ALP,OCN mRNA. Results Forskolin increased the ex-pression of Runx2, ALP, OCN mRNA as well as matrix mineralization in SCAPs, and the stimulation effects of For-skolin were enhanced by overexpressing NFIC gene. Conclusion The results indicate that NFIC can promote cAMP-induced differentiation of SCAPs.

Nfic regulates tooth root patterning and growth / 대한해부학회지

Molecular interactions between epithelium and mesenchyme are important for root formation. Nuclear factor I-C (Nfic) has been identified as a key regulator of root formation. However, the mechanisms of root formation and their interactions between Hertwig's epithelial root sheath (HERS) and mesenchyme remain unclear. In this study, we investigated the role of Nfic in root patterning and growth during molar root development. The molars of Nfic knockout mice exhibited an enlarged pulp chamber and apical displacement of the pulpal floor, characteristic features of taurodontism, due to delayed furcation formation. In developing molar roots of mutant mice at P14, BrdU positive cells decreased in the apical mesenchyme of the elongation region whereas those cells increased in the dental papilla of the furcation region. Whereas cytokeratin 14 and laminin were localized in HERS cells of mutant molars, Smoothened (Smo) and Gli1 were downregulated in preodontoblasts. In contrast, cytokeratin 14 and Smo were localized in the cells of the furcation region of mutant molars. These results indicate that Nfic regulates cell proliferation in the dental mesenchyme and affects the fate of HERS cells in a site-specific manner. From the results, it is suggested that Nfic is required for root patterning and growth during root morphogenesis.

Effect of NFI-C on the Expression of Smad and TGF-betaR1 / 대한해부학회지

NFI-C null mice demonstrate aberrant odontoblast differentiation and abnormal dentin formation, and thus develop molars lacking roots. However, other tissues and organs in the body including ameloblasts appear to be unaffected. Abnormal dentin in NFI-C null mice shares morphological similarities to the osteodentin that is formed in dental caries. However, little is known about the relationship between NFI-C and osteodentin formation. In this study, to elucidate the molecular characteristics of abnormal odontoblast in NFI-C null mice, we examined the levels of Ask-1, Cdc-2, Smad2/3, and TGF-betaR1 in cell culture and tissue sections from NFI-C null mice using immunofluorescence and immunohistochemistry. NFI-C protein was localized in the nucleus and cytoplasm of normal odontoblasts in vitro. Ask-1 and Cdc-2 proteins were shown in the perinuclear cytoplasm of both normal and NFI-C null mice. There were no differences in the pattern of production of Ask-1 and Cdc-2 proteins between normal and NFI-C null mice. Smad2/3 was not found in the odontoblast and subodontoblastic cells of the normal mice, whereas NFI-C null mice showed Smad2/3 immunoreactivity in the odontoblasts and subodontoblastic cells of the tooth pulp. TGF-betaR1 was weakly immunopositive in the odontoblast and subodontoblastic cells of normal mice, whereas it was detected strongly in the subodontoblastic cells of the NFI-C null mice. These results suggest that disruption of NFI-C increased the expression of Smad2/3 and TGF-betaR1 in developing odontoblasts and consequently caused abnormal dentin formation, similar to osteodentin.