Abstract:
Background: Tissue-engineered heart valves (TEHVs) are promising new heart valve substitutes for valvular heart disease. The Notch signaling pathway plays a critical role in the development of congenital heart valves. Objective: To investigate the role of the Notch signaling pathway in the construction of TEHVs. Methods: The induced endothelial cells, which act as seed cells, were differentiated from adipose-derived stem cells and were treated with Jagged-1 (JAG-1) protein and γ-secretase inhibitor (DAPT, N-[N-(3,5-difluorophenacetyl)-l-alanyl]-s-phenylglycine t-butyl ester), respectively. Cell phenotypic changes, the expression of proteins relating to the epithelial-mesenchymal transition (EMT), and changes in paxillin expression were detected. Decellularized valve scaffolds were produced from decellularized porcine aortic valves. The seed cells were them inoculated into Matrigel-coated flap scaffolds for complex culture and characterization. Results: JAG-1 significantly reduced apoptosis and promoted the seeded cells\' proliferation and migration ability, in contrast to the treatment of DAPT. In addition, the expression of EMT-related proteins, E-cadherin and N-cadherin, was significantly increased after treatment with JAG-1 and was reduced after the application of DAPT. Meanwhile, the adhesive-related expression of paxillin and fibronectin proteins was increased after the activation of Notch1 signaling and vice versa. Of interest, activation of the Notch1 signaling pathway resulted in more closely arranged cells on the valve surface after recellularization. Conclusion: Activation of the JAG-1/Notch1 signaling pathway increased seeded cells\' proliferation and migratory ability and promoted the EMT and adhesion of seed cells, which was conducive to binding to the matrix, facilitating accelerated endothelialization of TEHVs.
摘要:
背景:组织工程心脏瓣膜(TEHVs)是治疗心脏瓣膜病的新型心脏瓣膜替代品。Notch信号通路在先天性心脏瓣膜的发育中起着至关重要的作用。
目的:研究Notch信号通路在TEHV构建中的作用。
方法:诱导的内皮细胞,作为种子细胞,从脂肪来源的干细胞分化,并用Jagged-1(JAG-1)蛋白和γ-分泌酶抑制剂(DAPT,分别为N-[N-(3,5-二氟苯乙酰基)-1-丙氨酰]-s-苯基甘氨酸叔丁基酯)。细胞表型变化,与上皮-间质转化(EMT)相关的蛋白质的表达,并检测到paxillin表达的变化。从脱细胞猪主动脉瓣产生脱细胞瓣膜支架。将种子细胞接种到Matrigel涂覆的皮瓣支架中,以进行复杂的培养和表征。
结果:JAG-1显著减少细胞凋亡,促进细胞增殖和迁移能力,与DAPT的治疗相反。此外,EMT相关蛋白的表达,E-Cadherin和N-Cadherin,用JAG-1治疗后显着增加,应用DAPT后降低。同时,Notch1信号激活后,Paxillin和纤连蛋白的粘附相关表达增加,反之亦然。有趣的是,Notch1信号通路的激活导致再细胞化后瓣膜表面细胞排列更紧密。
结论:激活Jagged-1/Notch1信号通路增加了种子细胞的增殖和迁移能力,促进了种子细胞的EMT和粘附,这有利于与基质结合,促进TEHVs加速内皮化。