Electroactive Membranes Promoted Odontogenic Differentiation By Reversing Dpscs Senescence

To investigate the role and mechanism of polypyrrole (PPy)-modified poly(vinylidene fluoridetrifluoroethylene) (P(VDF-TrFE)) electroactive membranes in promoting odontogenic differentiation by reversing senescence of dental pulp stem cells (DPSCs). P(VDF-TrFE) membranes were fabricated via spin-coating and contact polarization. PPy was deposited on P(VDF-TrFE) membranes using electrochemical polymerization. Physical and chemical properties of electroactive membranes were characterized. Cell viability, proliferation, and adhesion of senescent DPSCs cultured on electroactive membranes were analyzed. ROS clearance, senescence reversal, and odontogenic differentiation were further investigated. The molecular mechanisms underlying PPy-P(VDF-TrFE)-mediated senescence reversal and the promotion of odontogenic differentiation were also explored. After the addition of PPy, the electroactive membranes exhibited increased β-phase content, surface hydrophilicity, and surface potential (all p < 0.05). PPy-P(VDF-TrFE) also significantly reduced intracellular ROS levels, β-galactosidase activity, and senescence-associated protein expression including p-p53/p53, p21and p16, while upregulating p-Rb/Rb and odontogenic markers including DSPP, DMP1 and OCN (all p < 0.05). RNA sequencing revealed enrichment of differentially expressed genes in the PI3K/Akt pathway. Western blot confirmed elevated ratios of p-PI3K/PI3K, p-Akt/Akt, and p-MDM2/MDM2 in PPy-P(VDF-TrFE)-treated DPSCs (p < 0.05). PPy-P(VDF-TrFE) electroactive membranes could promote odontogenic differentiation by reversing DPSC senescence via PI3K/Akt/MDM2 pathways, demonstrating a potential application of electroactive biomaterials for reparative dentin formation in direct pulp capping.