ABSTRACT
Introduction: Human periodontal ligament stem cells (hPDLSCs) are stem cells found near the tooth periodontal ligament. These cels are involved in the regeneration of the periodontal ligament and alveolar bone during orthodontic treatment and chronic periodontitis.
Objectives: The Homeobox gene HOXA10 regulates the osteogenic differentiation of stem cells. However, the role of HOXA10 in hPDLSCs remains unclear. Therefore, we studied the effects of HOXA10 on human PDLSC osteogenic differentiation in vitro.
Methods: First, hPDLSCs were isolated and characterized. Second, we assessed the effects of overexpression and knockdown of HOXA10 on PDLSC osteogenic differentiation. Finally, the specific Wnt signaling pathway activator lithium chloride (LiCl) and inhibitor ICG-001 were used to investigate the involvement of the Wnt signaling pathway in HOXA10-induced regulation of osteogenic differentiation.
Results: Overexpressing HOXA10 inhibited PDLSC osteogenic differentiation in vitro, shown by ALP and Alizarin Red staining, while HOXA10 knockdown demonstrated the opposite effects. HOXA10 negatively regulated nuclear β-catenin and osteogenic differentiation markers including alkaline phosphatase (ALPL) and integrin-binding sialoprotein (IBSP). Upregulating HOXA10 reduced nuclear β-catenin and increased DKK1 expression. However, HOXA10 knockdown enhanced nuclear β-catenin accumulation and reduced DKK1 expression. These negative effects on osteogenic differentiation by HOXA10 overexpression were restored by the Wnt/β-catenin pathway activator LiCl. The increased osteogenic differentiation effects of HOXA10 knockdown were antagonized by ICG-001, a Wnt pathway inhibitor.
Conclusion: These data demonstrate that HOXA10 inhibits the osteogenic differentiation of periodontal ligament stem cells by regulating β-catenin localization and DKK1.
Author’s contribution
All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Chengze Wang, Yongzheng Li, Ke Yu, Zhiwei Jiang, and Ying Wang. The first draft of the manuscript was written by Chengze Wang and Guoli Yang, and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.
Disclosure statement
The authors declare that they have no competing interests.