Ginsenoside Rb1 restores dental pulp by promoting odontogenic differentiation of dental pulp stem cells via the TGF-β/Smad signaling pathway

Background Dental surgery is a common treatment for pulpitis, which can lead to decreased pulp vitality. A novel approach is needed to induce reparative dentin formation without pulp removal. Ginsenoside Rb1 (G-Rb1) is known for its regenerative properties in various diseases. This study aimed to examine the odontogenic differentiation-promoting effects of G-Rb1 in human dental pulp stem cells (hDPSCs) and a rat pulpotomy model, and explore the underlying molecular mechanisms. Methods hDPSCs were extracted from supernumerary teeth and cultured with 10 μg/mL G-Rb1. Odontoblastic differentiation was assessed through real-time PCR, western blot, ALP activity, and Alizarin Red S staining. RNA sequencing was performed to confirm the effects of G-Rb1 on odontogenesis of hDPSCs. The effects in the rat pulpotomy model were evaluated by examining reparative dentin formation using von Kossa staining. Results G-Rb1 was non-cytotoxic and significantly enhanced hDPSC migration and odontoblastic differentiation in hDPSCs, upregulating the expression of odontogenic markers, DMP1 and DSPP, and increasing mineralized nodule deposition. RNA sequencing identified the TGF-β/Smad pathway as a key mechanism underlying these effects, which was confirmed by evaluating the expression of pathway-related proteins. In vivo analysis demonstrated significantly higher reparative dentin formation in the G-Rb1-treated group compared to the control group. Conclusion G-Rb1 promotes odontoblastic differentiation in hDPSCs and enhances reparative dentin formation via the TGF-β/Smad signaling pathway. These findings highlight the potential of G-Rb1 as a therapeutic agent for dental pulp repair and regeneration.