Abstract：
Biophysical and biochemical cues of biomaterials can regulate cell behaviors. Dental pulp stem cells (DPSCs) in pulp tissues can differentiate to odontoblast-like cells and secrete reparative dentin to form a barrier to protect the underlying pulp tissues and enable complete pulp healing. Promotion of the odontogenic differentiation of DPSCs is essential for dentin regeneration. The effects of the surface potentials of biomaterials on the adhesion and odontogenic differentiation of DPSCs remain unclear. Here, poly(vinylidene fluoride-trifluoro ethylene) (P(VDF-TrFE)) films with different surface potentials were prepared by the spin-coating technique and the contact poling method. The cytoskeletal organization of DPSCs grown on P(VDF-TrFE) films was studied by immunofluorescence staining. Using atomic force microscopy (AFM), the lateral detachment forces of DPSCs from P(VDF-TrFE) films were quantified. The effects of electrical stimulation generated from P(VDF-TrFE) films on odontogenic differentiation of DPSCs were evaluated in vitro and in vivo. The unpolarized, positively polarized, and negatively polarized films had surface potentials of -52.9, +902.4, and -502.2 mV, respectively. DPSCs on both negatively and positively polarized P(VDF-TrFE) films had larger cell areas and length-to-width ratios than those on the unpolarized films (P < 0.05). During the detachment of DPSCs from P(VDF-TrFE) films, the average magnitudes of the maximum detachment forces were 29.4, 72.1, and 53.9 nN for unpolarized, positively polarized, and negatively polarized groups, respectively (P < 0.05). The polarized films enhanced the mineralization activities and increased the expression levels of the odontogenic-related proteins of DPSCs compared to the unpolarized films (P < 0.05). The extracellular signal-regulated kinase (ERK) signaling pathway was involved in the odontogenic differentiation of DPSCs as induced by surface charge. In vivo, the polarized P(VDF-TrFE) films enhanced adhesion of DPSCs and promoted the odontogenic differentiation of DPSCs by electrical stimulation, demonstrating a potential application of electroactive biomaterials for reparative dentin formation in direct pulp capping.
摘要：
生物材料的生物物理和生化线索可以调节细胞行为。牙髓组织中的牙髓干细胞(DPSC)可以分化为成牙本质细胞样细胞并分泌修复性牙本质以形成屏障以保护下面的牙髓组织并实现完全牙髓愈合。促进DPSC的牙源性分化对于牙本质再生至关重要。生物材料的表面电位对DPSC的粘附和牙源性分化的影响尚不清楚。这里,通过旋涂技术和接触极化法制备了具有不同表面电位的聚（偏氟乙烯-三氟乙烯）（P（VDF-TrFE））薄膜。通过免疫荧光染色研究了在P（VDF-TrFE）膜上生长的DPSC的细胞骨架组织。使用原子力显微镜（AFM），定量DPSC与P(VDF-TrFE)膜的侧向分离力。在体外和体内评估了从P（VDF-TrFE）膜产生的电刺激对DPSC牙源性分化的影响。不极化的，正极化，负极化薄膜的表面电势为-52.9、+902.4和-502.2mV，分别。负极化和正极化P（VDF-TrFE）薄膜上的DPSC比非极化薄膜上的DPSC具有更大的电池面积和长宽比（P<0.05）。在DPSC从P（VDF-TrFE）薄膜上分离的过程中，非极化的最大分离力的平均大小为29.4、72.1和53.9nN，正极化，和负极化的基团，分别为(P<0.05)。与未极化膜相比，极化膜增强了DPSC的矿化活性，并增加了牙源性相关蛋白的表达水平（P<0.05）。细胞外信号调节激酶（ERK）信号通路参与表面电荷诱导的DPSCs牙源性分化。在体内,极化P（VDF-TrFE）膜通过电刺激增强DPSCs的粘附并促进DPSCs的牙源性分化，证明了电活性生物材料在直接盖髓中修复性牙本质形成中的潜在应用。
