The role and molecular mechanism of Shikonin in promoting odontogenic differentiation of human dental pulp stem cells.

BACKGROUND

In tissue engineering applications, human dental pulp stem cells (hDPSCs) are an optimal biological resource due to their ability to regenerate the pulp-dentin complex through odontogenic differentiation. Shikonin (SHI), a red-purple naphthoquinone compound extracted from the root of Lithospermum erythrorhizon, has shown promise in this context. However, comprehensive studies on SHI's capacity to promote odontogenic differentiation in hDPSCs are limited. This study aims to investigate the effects of SHI on the odontogenic differentiation of hDPSCs and explore the underlying mechanisms involved.

MATERIALS AND

METHODS

In vitro experiments were conducted using cell counting kit‑8 assays (CCK-8), Alkaline phosphatase (ALP) / Alizarin red S (ARS) staining, ALP activity measurements, Quantitative real-time polymerase chain reaction (qRT-PCR), and Western blot analysis. In vivo, subcutaneous scaffolds loaded with hDPSCs were implanted into the dorsum of nude mice, followed by histological and immunohistochemical analyses.

RESULTS

Results indicated that SHI, at concentrations up to 0.5 µM, did not significantly affect the proliferation of hDPSCs. However, at a concentration of 0.25 µM, SHI promoted the odontogenic differentiation of hDPSCs in vitro. Correspondingly, in vivo findings demonstrated that SHI enhanced the formation of a mineralized matrix by hDPSCs. Furthermore, inhibition of the MAPK pathway was found to block the SHI-induced upregulation of odontogenic differentiation markers in hDPSCs.

CONCLUSION

These findings suggest that SHI may promote odontogenic differentiation of hDPSCs by activating MAPK signaling pathways, contributing to the exploration of new strategies for pulp-dentin regeneration.