The Jagged-1/Notch1 Signaling Pathway Promotes the Construction of Tissue-Engineered Heart Valves.

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 gamma-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. Impact statement Tissue-engineered heart valves have been considered as an alternative for heart valve. Jagged-1 (JAG-1)/Notch signaling pathway plays an important regulatory role during heart valve development in the embryonic period. Activation of JAG-1/Notch signaling pathway could promote proliferation and migration ability of induced endothelial cells derived from the differentiation of adipose-derived stem cells. Activation of JAG-1/Notch signaling pathway also improves the epithelial-mesenchymal transition of induced endothelial cells and increases their adhesion ability. Moreover, the activation of JAG-1/Notch signaling pathway in seeded cells was beneficial to the recellularization of decellularized valve scaffolds. These results provided a novel strategy for the tissue-engineered heart valves.