Dental Pulp Stem Cell Polarization: Effects of Biophysical Factors

Decellularized rat submandibular gland as an alternative scaffold for dental pulp regeneration

Introduction: Decellularized extracellular matrix has been recognized as an optimal scaffold for dental pulp regeneration. However, the limited amount of native dental pulp tissue restricts its clinical applications. The submandibular gland shares some basic extracellular matrix components and characteristics with dental pulp. However, whether decellularized submandibular gland extracellular matrix (DSMG) can be used as an alternative scaffold for dental pulp regenerative medicine is unclear. Methods: Thus, we successfully decellularized the whole rat submandibular gland and human dental pulp, and then conducted in vitro and in vivo studies to compare the properties of these two scaffolds for dental pulp regeneration. Results: Our results showed that extracellular matrix of the submandibular gland had great similarities in structure and composition with that of dental pulp. Furthermore, it was confirmed that the DSMG could support adhesion and proliferation of dental pulp stem cells in vitro. In vivo findings revealed that implanted cell-seeded DSMG formed a vascularized dental pulp-like tissue and expressed markers involved in dentinogenesis and angiogenesis. Discussion: In summary, we introduced a novel accessible biological scaffold and validated its effectiveness as an extracellular matrix-based tissue engineering scaffold for dental pulp regenerative therapy.

Functionalized self-assembled peptide RAD/Dentonin hydrogel scaffold promotes dental pulp regeneration

RADA16-I is an ion-complementary self-assembled peptide with a regular folded secondary conformation and can be assembled into an ordered nanostructure. Dentonin is an extracellular matrix phosphate glycoprotein functional peptide motif-containing RGD and SGDG motifs. In this experiment, we propose to combine RAD and Dentonin to form a functionalized self-assembled peptide RAD/Dentonin hydrogel scaffold. Furthermore, we expect that the RAD with the addition of functional motif Dentonin can promote pulp regeneration. The study analyzed the physicochemical properties of RAD/Dentonin through circular dichroism, morphology scanning, and rheology. Besides, we examined the scaffold's biocompatibility by immunofluorescent staining, CCK-8 method, Live/Dead fluorescent staining, and 3D reconstruction. Finally, we applied ALP activity assay, RT-qPCR, and Alizarin red S staining to detect the effect of RAD/Dentonin on the odontogenic differentiation of human dental pulp stem cells (hDPSCs). The results showed that RAD/Dentonin spontaneously assembles into a hydrogel with aβ-sheet-based nanofiber network structure.In vitro, RAD/Dentonin has superior biocompatibility and enhances adhesive proliferation, migration, odontogenic differentiation, and mineralization deposition of hDPSCs. In conclusion, the novel self-assembled peptide RAD/Dentonin is a new scaffold material suitable for cell culture and has promising applications as a scaffold for endodontic tissue engineering.