多功能血管支架涂层的构建和生物相容性研究
发布时间：2018-08-08 11:51
【摘要】：防止支架再狭窄和晚期血栓的发生对血管支架植入成功起到至关重要的作用。药物洗脱支架(DES)通过释放药物抑制SMCs增殖,大大降低了血管支架再狭窄的风险,其问世给冠状动脉介入治疗带来了里程碑式的发展。然而,支架洗脱的药物同时也抑制了ECs的生长,延缓了支架表面内皮化的进程,进而增加了晚期血栓(LST)发生的风险。在证实支架表面可通过诱导内皮层再生起到降低支架再狭窄和LST发生率后,快速内皮化被广泛认为是解决支架再狭窄和LST的重要途径。然而,大部分的研究工作仅片面的改善支架表面ECs生长环境,而忽略了支架在临床使用中的抗增生和抗凝血的实际需要,导致其研发的支架在临床使用中未能达到预期的理想效果。基于此,本论文提出了一个理想支架表面性能设计概念：即支架表面应具有一个类似天然ECs层微环境,既能满足于临床上抗凝血和抗增生的需求,同时又利于选择性的促进ECs生长,以实现促进病变血管自我修复的目的。基于此,本论文通过致力于构建新型表面涂层改性策略,以实现多功能血管支架的表面设计。本论文工作设计了两类具有潜在应用价值的聚合涂层(即等离子体聚合涂层和贻贝灵感聚多巴胺涂层)用于固定具有多重生物学功能的活性分子。论文的第一部分侧重于研究这两类新引入聚合涂层作为支架改性平台的可行性。研究证明,这两类涂层不仅与316LSS (316LSS)支架基底具有优异的结合力,且均可顺应支架在压缩和撑开过程所带来的复杂形变而未出现开裂和剥离现象,同时具备良好的细胞相容性,满足了作为支架涂层的基本应用前提和要求。在此基础上,本论文借助于静电自组装或化学偶联方法,在富含胺基官能团的等离子体聚烯丙胺薄膜(PPAam)表面固定具有多重生物学功能的潜在活性分子如：没食子酸(GA)、比伐卢定(BVLD)和肝素(Heparin)或具有一氧化氮(NO)催化活性功能的分子3,3'-二硒代二丙酸(SeDPA)。受多巴胺自聚的启发,选用含邻苯二酚结构的化合物如邻苯二酚(Ca)、多巴胺(Dopamine)、GA或表没食子儿茶素没食子酸酯(EGCG)和具有NO催化活性的双硫化合物如胱胺(CySA)或联硒化合物硒代胱胺(SeCA)为反应原材料,基于碱性条件下伯胺基与酚羟基／琨基之间的迈克尔加成和西佛碱共价反应的特性,采用简单的一步“表面浸涂法”在支架表面制备了具有内源性NO催化活性的聚合粘附涂层。系统的生物相容性评价表明,本论文所设计五种功能性涂层都具有优异的促ECs生长能力。此外,BVLD功能化PPAam涂层(BVLD-PPAam)通过抑制凝血酶的活性途径表现出优异的抗凝血功能；GA功能化PPAam涂层(GA-PPAam)通过诱导平滑肌细胞(SMCs)凋亡表现出显著的抑制SMCs增殖能力。更值得关注的是,肝素功能化PPAam涂层(Hep-PPAam)、SeDPA功能化PPAam (SeDPA-PPAam)和CySA/SeCA与具有邻苯二酚结构的化合物的共聚合粘附NO催化涂层表现出多重生物学功能,即优异的抗凝血性和选择性的抑制SMCs增殖和促进ECs生长性能。其中,还发现肝素化涂层表面的ECs生长行为与其表面肝素固定量有着密切相关性,表面肝素固定量在低于3 μg/cm2时才有利于ECs生长。SeDPA-PPAam和NO催化活性聚合粘附涂层都表现出长期、持续催化内源性S-亚硝基硫醇(RSNO)分解产生NO能力。涂层催化产生的NO赋予其表面类天然内皮层的生物学功能,不仅具有特异性抑制胶原诱导的血小板激活、聚集和抑制SMCs粘附和增殖功能,同时还能显著促进ECs迁移、粘附和增殖。更为重要的是,NO催化涂层通过持续性催化NO产生,可构建出具有选择性促进ECs而抑制SMCs生长的微环境,加速了支架表面体内内皮化进程。此外,耦合CySA和SeCA的NO催化活性聚合粘附涂层不仅具有调控NO释放速率的能力,而且能适用于具有复杂几何形状器械和广泛种类的基体材料的表面改性。本论文不仅证实了通过固定具有多重生物学功能的活性分子可构建多功能血管支架涂层的可行性,还探索了多功能支架涂层材料与血液、ECs和SMCs的作用机制。这些研究结果为设计全新一代血管支架可能性提供了有力的理论基础和技术支撑。在本论文研究的功能涂层中,以Hep-PPAam以及NO催化涂层最具应用潜力和价值。
[Abstract]:Prevention of stent restenosis and late thrombus plays a vital role in the success of stent implantation. Drug eluting stent (DES) reduces the risk of restenosis by releasing drugs to inhibit SMCs proliferation, which has brought milestone development to coronary intervention. However, stent eluting drugs have been developed. It also inhibits the growth of ECs, delays the process of endothelialization on the surface of the scaffold and increases the risk of late thrombus (LST). After the stent restenosis and LST incidence can be reduced by inducing endothelium regeneration, rapid endothelialization is widely recognized as an important way to solve the stent restenosis and LST. Most of the research work only unilaterally improves the ECs growth environment on the surface of the scaffold, but neglects the practical needs of the scaffolding in the clinical use of anticoagulant and anticoagulant, which leads to the failure to achieve the desired effect in clinical use. Based on this, this paper presents an ideal design concept of the surface performance of the scaffold: The surface of the scaffold should have a similar natural ECs layer microenvironment, which can not only meet the needs of anticoagulation and anti proliferation in clinical, but also facilitate the selective promotion of ECs growth, in order to promote the self repair of the diseased vessels. Based on this, this paper aims to implement the Gou Jianxin type surface coating modification strategy to achieve multifunction blood vessels. In this paper, two types of polymerized coatings with potential application value (plasma polymerization coating and mussel inspired polydopamine coating) are designed to immobilizing active molecules with multiple biological functions. The first part of the thesis focuses on the study of these two new types of polymeric coatings as a scaffold modification platform. It is proved that the two kinds of coatings not only have excellent bonding force with the 316LSS (316LSS) support substrate, but also comply with the complex deformation of the stent in the process of compression and distraction, without cracking and peeling, and have good cellular compatibility, which satisfies the basic application and requirements of the scaffold coating. On this basis, this paper uses electrostatic self-assembly or chemical coupling method to immobilization potential active molecules with multiple biological functions on the surface of plasma polyallyl amine film (PPAam) rich in amine based functional groups, such as gallic acid (GA), bioludine (BVLD) and heparin (Heparin) or with nitric oxide (NO) catalytic activity. Molecular 3,3'- two selenium two propionic acid (SeDPA). Inspired by the self polymerization of dopamine, compounds containing catechol structures such as catechol (Ca), dopamine (Dopamine), GA or epigallocatechin gallate (EGCG) and NO catalyzed disulfur compounds such as cysteamine (CySA) or selenium selenocysteine (SeCA) are used as reactive ingredients Materials, based on the characteristics of the covalent reaction of Michael addition and SIF base between primary amine group and phenolic hydroxyl / Kun base under alkaline conditions, a simple one step "surface dip coating" was used to prepare a polymeric adhesion coating with endogenous NO catalytic activity on the surface of the scaffold. The biocompatibility evaluation of the system showed that five kinds of work designed in this paper were designed. The energetic coating has excellent ECs growth promoting ability. In addition, BVLD functionalized PPAam coating (BVLD-PPAam) shows excellent anticoagulant function by inhibiting the activity of thrombin; GA functional PPAam coating (GA-PPAam) shows significant inhibition of SMCs proliferation by inducing apoptosis of smooth muscle cells (SMCs). Heparin functionalized PPAam coating (Hep-PPAam), SeDPA functionalized PPAam (SeDPA-PPAam) and CySA/SeCA and the copolymerization adhesive NO catalytic coating with catechol structure exhibit multiple biological functions, that is, excellent anticoagulant and selective inhibition of SMCs proliferation and ECs growth performance. The heparin coating surface is also found. The growth behavior of ECs is closely related to the amount of heparin immobilization on the surface. When the fixed amount of heparin on the surface is less than 3 u g/cm2, it is beneficial to ECs growth.SeDPA-PPAam and NO catalytic active polymeric adhesion coating for a long time, continuously catalyzing endogenous S- nitroso mercaptan (RSNO) decomposition to produce NO ability. The biological function of natural endothelium is not only specific to inhibit the activation of collagen induced platelets, aggregation and inhibition of SMCs adhesion and proliferation, but also significantly promote ECs migration, adhesion and proliferation. More importantly, the NO catalyzed coating catalyzes the production of NO through continuous catalysis, which can be constructed to selectively promote ECs and inhibit SM. The microenvironment of Cs growth accelerates the endothelialization process in the surface of the stent. In addition, the NO catalyzed polymerized adhesive coating coupled with the coupling of CySA and SeCA not only has the ability to regulate the rate of NO release, but also can be applied to surface modification with complex geometries and a wide variety of matrix materials. This paper not only confirmed the passing of the fixator in this paper. The feasibility of multi functional active molecules with multiple biological functions can be used to construct multi-functional stent coatings, and the mechanisms of multi-functional scaffold coating materials and blood, ECs and SMCs are also explored. These results provide a powerful theoretical basis and technical support for the design of a new generation of vascular scaffolds. The coating with Hep-PPAam and NO has the most potential and value in the coating.
【学位授予单位】：西南交通大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：R318.08;TG174.4
，
本文编号：2171704
[Abstract]:Prevention of stent restenosis and late thrombus plays a vital role in the success of stent implantation. Drug eluting stent (DES) reduces the risk of restenosis by releasing drugs to inhibit SMCs proliferation, which has brought milestone development to coronary intervention. However, stent eluting drugs have been developed. It also inhibits the growth of ECs, delays the process of endothelialization on the surface of the scaffold and increases the risk of late thrombus (LST). After the stent restenosis and LST incidence can be reduced by inducing endothelium regeneration, rapid endothelialization is widely recognized as an important way to solve the stent restenosis and LST. Most of the research work only unilaterally improves the ECs growth environment on the surface of the scaffold, but neglects the practical needs of the scaffolding in the clinical use of anticoagulant and anticoagulant, which leads to the failure to achieve the desired effect in clinical use. Based on this, this paper presents an ideal design concept of the surface performance of the scaffold: The surface of the scaffold should have a similar natural ECs layer microenvironment, which can not only meet the needs of anticoagulation and anti proliferation in clinical, but also facilitate the selective promotion of ECs growth, in order to promote the self repair of the diseased vessels. Based on this, this paper aims to implement the Gou Jianxin type surface coating modification strategy to achieve multifunction blood vessels. In this paper, two types of polymerized coatings with potential application value (plasma polymerization coating and mussel inspired polydopamine coating) are designed to immobilizing active molecules with multiple biological functions. The first part of the thesis focuses on the study of these two new types of polymeric coatings as a scaffold modification platform. It is proved that the two kinds of coatings not only have excellent bonding force with the 316LSS (316LSS) support substrate, but also comply with the complex deformation of the stent in the process of compression and distraction, without cracking and peeling, and have good cellular compatibility, which satisfies the basic application and requirements of the scaffold coating. On this basis, this paper uses electrostatic self-assembly or chemical coupling method to immobilization potential active molecules with multiple biological functions on the surface of plasma polyallyl amine film (PPAam) rich in amine based functional groups, such as gallic acid (GA), bioludine (BVLD) and heparin (Heparin) or with nitric oxide (NO) catalytic activity. Molecular 3,3'- two selenium two propionic acid (SeDPA). Inspired by the self polymerization of dopamine, compounds containing catechol structures such as catechol (Ca), dopamine (Dopamine), GA or epigallocatechin gallate (EGCG) and NO catalyzed disulfur compounds such as cysteamine (CySA) or selenium selenocysteine (SeCA) are used as reactive ingredients Materials, based on the characteristics of the covalent reaction of Michael addition and SIF base between primary amine group and phenolic hydroxyl / Kun base under alkaline conditions, a simple one step "surface dip coating" was used to prepare a polymeric adhesion coating with endogenous NO catalytic activity on the surface of the scaffold. The biocompatibility evaluation of the system showed that five kinds of work designed in this paper were designed. The energetic coating has excellent ECs growth promoting ability. In addition, BVLD functionalized PPAam coating (BVLD-PPAam) shows excellent anticoagulant function by inhibiting the activity of thrombin; GA functional PPAam coating (GA-PPAam) shows significant inhibition of SMCs proliferation by inducing apoptosis of smooth muscle cells (SMCs). Heparin functionalized PPAam coating (Hep-PPAam), SeDPA functionalized PPAam (SeDPA-PPAam) and CySA/SeCA and the copolymerization adhesive NO catalytic coating with catechol structure exhibit multiple biological functions, that is, excellent anticoagulant and selective inhibition of SMCs proliferation and ECs growth performance. The heparin coating surface is also found. The growth behavior of ECs is closely related to the amount of heparin immobilization on the surface. When the fixed amount of heparin on the surface is less than 3 u g/cm2, it is beneficial to ECs growth.SeDPA-PPAam and NO catalytic active polymeric adhesion coating for a long time, continuously catalyzing endogenous S- nitroso mercaptan (RSNO) decomposition to produce NO ability. The biological function of natural endothelium is not only specific to inhibit the activation of collagen induced platelets, aggregation and inhibition of SMCs adhesion and proliferation, but also significantly promote ECs migration, adhesion and proliferation. More importantly, the NO catalyzed coating catalyzes the production of NO through continuous catalysis, which can be constructed to selectively promote ECs and inhibit SM. The microenvironment of Cs growth accelerates the endothelialization process in the surface of the stent. In addition, the NO catalyzed polymerized adhesive coating coupled with the coupling of CySA and SeCA not only has the ability to regulate the rate of NO release, but also can be applied to surface modification with complex geometries and a wide variety of matrix materials. This paper not only confirmed the passing of the fixator in this paper. The feasibility of multi functional active molecules with multiple biological functions can be used to construct multi-functional stent coatings, and the mechanisms of multi-functional scaffold coating materials and blood, ECs and SMCs are also explored. These results provide a powerful theoretical basis and technical support for the design of a new generation of vascular scaffolds. The coating with Hep-PPAam and NO has the most potential and value in the coating.
【学位授予单位】：西南交通大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：R318.08;TG174.4
，
本文编号：2171704
本文链接：https://www.wllwen.com/yixuelunwen/swyx/2171704.html
