Dental Pulp Stem Cell Transplantation with 2,3,5,4 '-Tetrahydroxystilbene-2-O-beta-D-glucoside Accelerates Alveolar Bone Regeneration in Rats
JOURNAL OF ENDODONTICS
Authors: Lin, Chi-Yu; Kuo, Po-Jan; Chin, Yu-Tang; Weng, I-Tsen; Lee, Hao-Wei; Huang, Haw-Ming; Lin, Hung-Yun; Hsiung, Chao-Nan; Chan, Ya-Hui; Lee, Sheng-Yang
Abstract
Introduction: Although the therapeutic potential of human dental pulp stem cells (hDPSCs) has been studied for bone regeneration, the therapeutic efficiency needs further consideration and examinations for clinical applications. Thus, the aims of this study were to evaluate the effect of 2,3,5,4'-tetrahydroxystilbene-2-O-beta-D-glucoside (THSG) on the osteogenic differentiation of hDPSCs and to examine the therapeutic efficiency of the THSG-enhanced osseous potential of hDPSCs in alveolar bony defects of rats. Methods: Expressions of osteogenic messenger RNAs (including ALP, RUNX2, BGLAP, and AMBN) were examined by quantitative real-time polymerase chain reaction. Alizarin red S staining was conducted to analyze THSG-induced mineralization of hDPSCs. To investigate the regenerative effects of THSG-treated hDPSCs on dental alveolar bone, bony defects were created in male Sprague-Dawley rats. Defects were treated with Matrigel (Corning Inc, Corning, NY), hDPSCs, or hDPSCs + THSG. After 2 weeks, defect healing was evaluated by micro-computed tomographic and histologic analyses. Results: In the cell model, THSG induced osteogenesis-associated genes (ALP, RUNX2, and BGLAP) and an enamel-related gene (AMBN), resulting in mineralization as detected by alizarin red S staining after 2 weeks of treatment. In the animal model, THSG increased all parameters of bone formation (the relative bone volume, trabecular thickness, trabecular number, and trabecular separation) in alveolar bony defects of rats. THSG not only improved the quality of newly formed bone but also the quantity of new bone. Conclusions: These results showed important findings in revealing the THSG-enhanced osteogenic differentiation of hDPSCs and THSG-facilitated bone regeneration, which may provide an alternative option for cell-based regenerative therapy.
Notch signaling is involved in Fgf23 upregulation in osteocytes
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Authors: Tamamura, Yoshihiro; Sakamoto, Kei; Katsube, Ken-ichi; Yamaguchi, Akira
Abstract
Fgf23 acts as a phosphaturic factor secreted from osteocytes in bone, but the mechanism regulating Fgf23 is not fully understood. Here, we showed the colocalization of Fgf23, Notch, and Hes1, a downstream target of Notch signaling, in numerous osteocytes in cortical bone of femur in wild-type mice. We generated NICD (Notch intracellular domain)-transgenic mice driven by a 2.3 kb collagena alpha 1 (I) (Col1a1) promoter fragment. Western blot and RT-PCR analyses revealed upregulation of Notch protein and mRNA levels in the bones of transgenic mice compared with those in wild-type mice. In the transgenic mice, immunohistochemical studies demonstrated that numerous osteocytes and osteoblasts express Notch in the rib, whereas only osteoblasts exhibit Notch in the femur. NICD-transgenic mice were characterized by upregulation of Fgf23 mRNA levels in the rib but not in the femur compared with that in wild type mice. These mice exhibited dwarfism associated with an osteomalacia phenotype. The expression of Alpl, Cal1a1, and Bglap decreased in NICD-transgenic mice compared with wild-type mice. UMR-106 cells cultured on Jagged1-immobilized wells significantly increased Fgf23 expressions associating with upregulation of Hes1 and Hey1. These results imply that Notch signaling is a positive regulator for Fgf23 expression in osteocytes. (C) 2019 Elsevier Inc. All rights reserved.