多功能血管支架涂層的構(gòu)建和生物相容性研究
發(fā)布時間：2018-08-08 11:51
【摘要】：防止支架再狹窄和晚期血栓的發(fā)生對血管支架植入成功起到至關(guān)重要的作用。藥物洗脫支架(DES)通過釋放藥物抑制SMCs增殖,大大降低了血管支架再狹窄的風險,其問世給冠狀動脈介入治療帶來了里程碑式的發(fā)展。然而,支架洗脫的藥物同時也抑制了ECs的生長,延緩了支架表面內(nèi)皮化的進程,進而增加了晚期血栓(LST)發(fā)生的風險。在證實支架表面可通過誘導(dǎo)內(nèi)皮層再生起到降低支架再狹窄和LST發(fā)生率后,快速內(nèi)皮化被廣泛認為是解決支架再狹窄和LST的重要途徑。然而,大部分的研究工作僅片面的改善支架表面ECs生長環(huán)境,而忽略了支架在臨床使用中的抗增生和抗凝血的實際需要,導(dǎo)致其研發(fā)的支架在臨床使用中未能達到預(yù)期的理想效果。基于此,本論文提出了一個理想支架表面性能設(shè)計概念：即支架表面應(yīng)具有一個類似天然ECs層微環(huán)境,既能滿足于臨床上抗凝血和抗增生的需求,同時又利于選擇性的促進ECs生長,以實現(xiàn)促進病變血管自我修復(fù)的目的。基于此,本論文通過致力于構(gòu)建新型表面涂層改性策略,以實現(xiàn)多功能血管支架的表面設(shè)計。本論文工作設(shè)計了兩類具有潛在應(yīng)用價值的聚合涂層(即等離子體聚合涂層和貽貝靈感聚多巴胺涂層)用于固定具有多重生物學功能的活性分子。論文的第一部分側(cè)重于研究這兩類新引入聚合涂層作為支架改性平臺的可行性。研究證明,這兩類涂層不僅與316LSS (316LSS)支架基底具有優(yōu)異的結(jié)合力,且均可順應(yīng)支架在壓縮和撐開過程所帶來的復(fù)雜形變而未出現(xiàn)開裂和剝離現(xiàn)象,同時具備良好的細胞相容性,滿足了作為支架涂層的基本應(yīng)用前提和要求。在此基礎(chǔ)上,本論文借助于靜電自組裝或化學偶聯(lián)方法,在富含胺基官能團的等離子體聚烯丙胺薄膜(PPAam)表面固定具有多重生物學功能的潛在活性分子如：沒食子酸(GA)、比伐盧定(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)。受多巴胺自聚的啟發(fā),選用含鄰苯二酚結(jié)構(gòu)的化合物如鄰苯二酚(Ca)、多巴胺(Dopamine)、GA或表沒食子兒茶素沒食子酸酯(EGCG)和具有NO催化活性的雙硫化合物如胱胺(CySA)或聯(lián)硒化合物硒代胱胺(SeCA)為反應(yīng)原材料,基于堿性條件下伯胺基與酚羥基／琨基之間的邁克爾加成和西佛堿共價反應(yīng)的特性,采用簡單的一步“表面浸涂法”在支架表面制備了具有內(nèi)源性NO催化活性的聚合粘附涂層。系統(tǒng)的生物相容性評價表明,本論文所設(shè)計五種功能性涂層都具有優(yōu)異的促ECs生長能力。此外,BVLD功能化PPAam涂層(BVLD-PPAam)通過抑制凝血酶的活性途徑表現(xiàn)出優(yōu)異的抗凝血功能；GA功能化PPAam涂層(GA-PPAam)通過誘導(dǎo)平滑肌細胞(SMCs)凋亡表現(xiàn)出顯著的抑制SMCs增殖能力。更值得關(guān)注的是,肝素功能化PPAam涂層(Hep-PPAam)、SeDPA功能化PPAam (SeDPA-PPAam)和CySA/SeCA與具有鄰苯二酚結(jié)構(gòu)的化合物的共聚合粘附NO催化涂層表現(xiàn)出多重生物學功能,即優(yōu)異的抗凝血性和選擇性的抑制SMCs增殖和促進ECs生長性能。其中,還發(fā)現(xiàn)肝素化涂層表面的ECs生長行為與其表面肝素固定量有著密切相關(guān)性,表面肝素固定量在低于3 μg/cm2時才有利于ECs生長。SeDPA-PPAam和NO催化活性聚合粘附涂層都表現(xiàn)出長期、持續(xù)催化內(nèi)源性S-亞硝基硫醇(RSNO)分解產(chǎn)生NO能力。涂層催化產(chǎn)生的NO賦予其表面類天然內(nèi)皮層的生物學功能,不僅具有特異性抑制膠原誘導(dǎo)的血小板激活、聚集和抑制SMCs粘附和增殖功能,同時還能顯著促進ECs遷移、粘附和增殖。更為重要的是,NO催化涂層通過持續(xù)性催化NO產(chǎn)生,可構(gòu)建出具有選擇性促進ECs而抑制SMCs生長的微環(huán)境,加速了支架表面體內(nèi)內(nèi)皮化進程。此外,耦合CySA和SeCA的NO催化活性聚合粘附涂層不僅具有調(diào)控NO釋放速率的能力,而且能適用于具有復(fù)雜幾何形狀器械和廣泛種類的基體材料的表面改性。本論文不僅證實了通過固定具有多重生物學功能的活性分子可構(gòu)建多功能血管支架涂層的可行性,還探索了多功能支架涂層材料與血液、ECs和SMCs的作用機制。這些研究結(jié)果為設(shè)計全新一代血管支架可能性提供了有力的理論基礎(chǔ)和技術(shù)支撐。在本論文研究的功能涂層中,以Hep-PPAam以及NO催化涂層最具應(yīng)用潛力和價值。
[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.
【學位授予單位】：西南交通大學
【學位級別】：博士
【學位授予年份】：2014
【分類號】：R318.08;TG174.4
，
本文編號：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.
【學位授予單位】：西南交通大學
【學位級別】：博士
【學位授予年份】：2014
【分類號】：R318.08;TG174.4
，
本文編號：2171704
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