RESUMEN
Degradable magnesium alloy stents are considered to be ideal candidates to replace the traditional non-degradable stents for the treatment of cardiovascular diseases. However, bare magnesium alloy stents usually degrade too fast and show poor hemocompatibility and cytocompatibility, which seriously affects their clinical use. In this study, surface modification based on the MgF2 layer, polydopamine (PDA) coating, fucoidan and CAG peptides was performed on the Mg-Zn-Y-Nd (ZE21B) magnesium alloy with the purpose of improving its corrosion resistance, hemocompatibility and cytocompatibility for vascular stent application. After modification, the ZE21B alloy showed better corrosion resistance. Moreover, the lower hemolysis rate, platelet adhesion and activation, and fibrinogen adsorption and denaturation proved the improved hemocompatibility of modified ZE21B alloy in in vitro blood experiments. Furthermore, the co-immobilization of fucoidan and CAG peptides significantly promoted the adhesion, proliferation, migration and NO release of endothelial cells (ECs) on the modified ZE21B alloy, and meanwhile the modification with fucoidan and CAG peptides inhibited the adhesion and proliferation of smooth muscle cells (SMCs) and suppressed the expression of proinflammatory factors in the macrophages (MAs). The surface modification obviously enhanced the corrosion resistance, hemocompatibility and cytocompatibility of ZE21B alloy, and provided an effective strategy for the development of degradable vascular stents.
Asunto(s)
Aleaciones , Adhesión Celular , Magnesio , Ensayo de Materiales , Péptidos , Polisacáridos , Aleaciones/química , Aleaciones/farmacología , Polisacáridos/química , Polisacáridos/farmacología , Humanos , Péptidos/química , Péptidos/farmacología , Magnesio/química , Adhesión Celular/efectos de los fármacos , Animales , Proliferación Celular/efectos de los fármacos , Hemólisis/efectos de los fármacos , Corrosión , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Adhesividad Plaquetaria/efectos de los fármacos , Ratones , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/citología , Miocitos del Músculo Liso/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Propiedades de Superficie , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Organismos Acuáticos/química , Indoles , PolímerosRESUMEN
Magnesium alloy stents (MAS) have broad application prospects in the treatment of cardiovascular diseases. However, poor corrosion resistance and biocompatibility greatly limit the clinical application of MAS. In this work, the coating consisting of MgF2 layer, polydopamine layer, fucoidan and collagen IV was constructed on Mg-Zn-Y-Nd (ZE21B) alloy to improve its corrosion resistance and pro-endothelialization potential. The fucoidan and collagen IV in the coating could obviously enhance the hemocompatibility and pro-endothelialization potential respectively. Compared with bare ZE21B alloy, the fucoidan/collagen composite coating modified ZE21B alloy possessed lower corrosion current density and better corrosion resistance. Moreover, the modified ZE21B alloy exhibited relatively low hemolysis rate, fibrinogen adsorption and platelet adhesion in the blood experiments, suggesting the improved hemocompatibility. Furthermore, the modified ZE21B alloy favorably supported the adhesion and proliferation of vascular endothelial cells (ECs) and effectively regulated the phenotype of smooth muscle cells (SMCs), thus improving the pro-endothelialization potential of vascular stent materials. The fucoidan/collagen composite coating can significantly improve the corrosion resistance and pro-endothelialization potential of ZE21B alloy, showing great potential in the development of degradable MAS.
Asunto(s)
Células Endoteliales , Magnesio , Materiales Biocompatibles Revestidos/farmacología , Aleaciones/farmacología , Corrosión , Colágeno , Ensayo de MaterialesRESUMEN
As an urgently needed device for vascular diseases, the small-diameter vascular graft is limited by high thrombogenicity in clinical applications. Rapid endothelialization is a promising approach to construct an antithrombogenic inner surface of the vascular graft. The main bottleneck for rapid endothelialization is the adhesion, migration, and proliferation of endothelial cells (ECs) in situ of the small-diameter vascular graft. Herein, we innovatively fabricated an intelligent gene delivery small-caliber vascular graft based on electrospun poly(lactic acid-co-caprolactone) and gelatin for rapid in situ endothelialization. The graft surface was co-modified with EC adhesive peptide of Arg-Glu-Asp-Val (REDV) and responsive gene delivery system. REDV can selectively adhere ECs onto the graft surface; subsequently, the overexpressed matrix metalloproteinase by ECs can effectively cleave the linker peptide GPQGIWGQ-C; and finally, the gene complexes were intelligently and enzymatically released from the graft surface, and thereby, the gene can efficiently transfect ECs. Importantly, this enzymatically releasing gene surface has been proven to be safe and temporarily stable in blood flow owing to the biotin-avidin interaction to immobilize gene complexes on the inner surface of vascular grafts through the GPQGIWGQ-C peptide linker. It has the advantage of specifically adhering the ECs to the surface and smartly transfecting them with high transfection efficiency. The co-modified surface has been demonstrated to accelerate the luminal endothelialization in vivo, which might be attributed to the synergistic effect of REDV and effective gene transfection. Particularly, the intelligent and responsive gene release surface will open a new avenue to enhance the endothelialization of blood-contacting devices.
Asunto(s)
Células Endoteliales/metabolismo , Técnicas de Transferencia de Gen , Injerto Vascular , Animales , Western Blotting , Adhesión Celular , Proliferación Celular , Células Endoteliales de la Vena Umbilical Humana , Humanos , Metaloproteinasas de la Matriz/metabolismo , Microscopía Electrónica de Rastreo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
Although blood-contacting medical devices have been widely used in the biomedical field, their low endothelialization seriously limits their treatment success. Gene transfection can enhance the proliferation and migration of endothelial cells (ECs) in culture, yet using this technology to realize surface endothelialization still faces great challenges. Herein, we developed a matrix metalloproteinase (MMP) responsive gene delivery surface for in situ smart release of genes from the biomaterial surface upon EC attachment and adhesion. The released genes induced by ECs can, in turn, effectively transfect ECs and enhance the surface endothelialization. An MMP-responsive gene delivery surface (Au-MCP@NPs) was constructed by immobilizing gene complex nanoparticles (NPs) onto a Au surface with MMP-cleavable peptide (MCP) grafted via biotin-avidin interaction. The Au-MCP@NP surface was demonstrated to responsively release NPs under the action of MMPs. More importantly, ECs were effectively transfected on this surface, leading to enhanced proliferation/migration in vitro. The in situ surface endothelialization was evaluated via implanting Au-MCP@NPs into rat aortas. The in vivo results demonstrated that this smart Au-MCP@NP surface could lead to the localized upregulation of ZNF580 protein and accelerate in situ endothelialization. This smart MMP-responsive gene delivery surface provided a promising and powerful strategy for enhanced in situ endothelialization of blood-contacting medical devices.
Asunto(s)
Células Endoteliales/metabolismo , Técnicas de Transferencia de Gen , Metaloproteinasas de la Matriz/metabolismo , Animales , Aorta/citología , Aorta/metabolismo , Movimiento Celular , Células Cultivadas , Células Endoteliales/citología , Terapia Genética , Oro/química , Oro/metabolismo , Metaloproteinasas de la Matriz/química , Nanopartículas/química , Nanopartículas/metabolismo , Tamaño de la Partícula , Ratas , Ratas Sprague-Dawley , Propiedades de SuperficieRESUMEN
Surface modification by conjugating biomolecules has been widely proved to enhance biocompatibility of small-caliber artificial vascular grafts. In this study, we aimed at developing a multifunctional vascular graft that provides not only good hemocompatibility but also in situ rapid endothelialization. Herein, a vascular graft (inner diameter â¼2â¯mm) was fabricated by electrospinning with poly(lactic acid-co-caprolactone) and gelatin, and then biofunctionalized with antithrombotic peptide with sequence LTFPRIVFVLG (ACH11) and cell adhesion peptide with sequence CAG through adhesive poly(dopamine) coating. We developed this graft with the synergistic properties of low thrombogenicity and rapid endothelialization. The successful grafting of both CAG and ACH11 peptides was confirmed by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The surface micromorphology of the modified surfaces was observed by field emission scanning electron microscopy. Our results demonstrated that the multifunctional surface suppressed the denaturation of absorbed fibrinogen, hindered coagulation factor Xa activation, and inhibited platelet adhesion and aggregation. Importantly, this modified surface could selectively enhance endothelial cells adhesion, proliferation and release of nitric oxide. Upon in vivo implantation of 6â¯weeks, the multifunctional vascular graft showed improved patency and superior vascular endothelialization. Overall, the results effectively demonstrated that the co-immobilization of ACH11 and CAG provided a promising method for the improvement of hemocompatibility and endothelialization of vascular grafts. STATEMENT OF SIGNIFICANCE: Electrospun small-caliber vascular grafts are increasingly used to treat cardiovascular diseases. Despite their success related to their good biodegradation and mechanical strength, they have some drawbacks, such as low hemocompatibility and endothelialization. The single-function ligands are insufficient to modify surface with both good hemocompatibility and rapid endothelialization simultaneously. Therefore, we functionalized electrospun vascular graft by novel antithrombotic peptide and cell-adhesive peptide to construct superior anticoagulation and ECs-selective adhesion surface in present study. The multifunctional vascular grafts benefit for high long-term patency and rapid endothelialization.
Asunto(s)
Prótesis Vascular , Materiales Biocompatibles Revestidos/química , Fibrinolíticos/química , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Ensayo de Materiales , Péptidos/química , Injerto Vascular , Animales , Células Endoteliales de la Vena Umbilical Humana/citología , Humanos , Masculino , Conejos , Propiedades de SuperficieRESUMEN
Blood-contacting materials with antiplatelet aggregation and anticoagulant properties are in great demand in biomedical field. Herein, hydrophilic poly(ethylene glycol) (PEG) and antithrombotic peptide ACH11 were coimmobilized onto Au to develop a multifunctional surface with remarkable hemocompatibility, antiprotein adsorption, antiplatelet aggregation, anticoagulant properties, and good histocompatibility. PEG can not only help the surface resist nonspecific protein adsorption and improve its hemocompatibility but also be a benefit for the immobilized ACH11 to maintain its bioactivity in plasma. The anticoagulant peptide ACH11 can endow the surface with the ability of activated coagulation factor Xa (FXa) inhibition and antiplatelet aggregation activities. Au was first aminated with 2-aminoethanethiol through strong Au-S bond, and then it was reacted with PEG-ACH11 through active ester chemistry to prepare the multifunctional surface Au-PEG-ACH11, among which the heterobifunctional PEG served as a linker to immobilize antithrombotic ACH11. The surface chemical structure and composition quantified by attenuated total reflection Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy convinced us of the successful preparation of the PEG-ACH11 modified Au surface. The surface micromorphology and topography of the modified surfaces were observed by field emission scanning electron microscopy and atomic force microscopy. The good hydrophilicity of the modified Au surface was confirmed by water contact analysis. Enzyme immunoassay analysis demonstrated that the activation level of FXa in plasma after incubation with Au-PEG-ACH11 was obviously lower than that in control groups. In vitro hemocompatibility evaluation, including hemolysis rate, denaturation of adsorbed fibrinogen, and platelet adhesion and activation, indicated that Au-PEG-ACH11 possessed good hemocompatibility. In vivo subcutaneous implantation assay also confirmed the milder tissue response of Au-PEG-ACH11. These results indicated that the multifunctional surface has great potential for biomedical application.
RESUMEN
Artificial small-caliber vascular grafts are still limited in clinical application because of thrombosis, restenosis, and occlusion. Herein, a small-caliber vascular graft (diameter 2 mm) is fabricated from poly(ε-caprolactone)-b-poly(isobutyl-morpholine-2,5-dione) (PCL-PIBMD) and silk fibroin (SF) by electrospinning technology and then biofunctionalized with low-fouling poly(ethylene glycol) (PEG) and two cell-adhesive peptide sequences (CREDVW and CAGW) with the purpose of enhancing antithrombogenic activity and endothelialization. The successful grafting of PEG and peptide sequences is confirmed by X-ray photoelectron spectroscopy. The suitable surface wettability of the modified vascular graft is testified by water contact angle analysis. The surface hemocompatibility is verified by platelet adhesion assays and protein adsorption assays, and the results demonstrate that both platelet adhesion and protein adsorption on the biofunctionalized surface are significantly reduced. In vitro studies demonstrate that the biofunctionalized surface with suitable hydrophilicity and cell-adhesive peptides can selectively promote the adhesion, spreading, and proliferation of human umbilical vein endothelial cells. More importantly, compared with control groups, this biofunctionalized small-caliber vascular graft shows high long-term patency and endothelialization after 10 weeks of implantation. The biofunctionalization with PEG and two cell-adhesive peptide sequences is an effective method to improve the endothelialization and long-term performance of synthetic vascular grafts.