脑心通对氧化低密度脂蛋白诱导血管平滑肌细胞增殖及凋亡的影响

血管平滑肌细胞(VSMC)的异常增殖是动脉粥样硬化(AS)形成的关键因素.研究表明,氧化型低密度脂蛋白(oxLDL)可以刺激VSMC的增殖,促进AS的发生和发展.应用药物抑制VSMC增殖可以有效地减少AS的发生.     

大鼠星形胶质细胞Toll样受体表达谱

目的探索Toll样受体4(TLR4)表达定位,揭示星形胶质细胞(AS)参与阿尔茨海默病(AD)炎症机制的可能分子机制。方法取新生1³ d的SD大鼠皮层进行星形胶质细胞的培养,传代纯化。细胞免疫荧光双标法鉴定传代后的AS及其纯度。实时PCR检测正常AS中TLRs表达谱。细胞免疫荧光双标法鉴定TLR4在AS的表达定位。结果传代培养可以纯化AS;AS表达TLR13 d的SD大鼠皮层进行星形胶质细胞的培养,传代纯化。细胞免疫荧光双标法鉴定传代后的AS及其纯度。实时PCR检测正常AS中TLRs表达谱。细胞免疫荧光双标法鉴定TLR4在AS的表达定位。结果传代培养可以纯化AS;AS表达TLR1¹1,但不同的TLRs表达量不同,其中TLR4表达水平相对较高,并且TLR4表达定位于胞膜和胞质。结论 AS参与AD炎症机制的可能分子机制。     

中药抑制血管平滑肌增殖和迁移的作用机制研究概况

综述中药抑制血管平滑肌细胞(VSMC)增殖和迁移作用机制的相关文献。VSMC主要存在于血管壁中膜,参与血管的收缩/舒张反应,进而维持正常的血压水平。在众多血管重构因子、炎症、机械损伤、高血压等影响下,中膜VSMC增殖、肥大并向内皮下迁移是导致内膜增厚、血管重构的重要病理基础,在动脉粥样硬化(AS)、经皮冠状动脉介入治疗(PCI)术后再狭窄的发生发展过程中起着十分关键的作用。如何有效维持VSMC收缩表型,抑制其异常增殖和迁移已成为AS、高血压、PCI术后再狭窄等心血管病的重要防治策略。     

氧化低密度脂蛋白损伤血管内皮细胞与平滑肌细胞增殖相关性研究

氧化修饰低密度脂蛋白(oxidized low-densitylipoprotein,ox-LDL)损伤血管内皮细胞(VEC)是动脉粥样硬化(AS)形成的重要因素之一。VEC结构和功能的损伤及血管平滑肌细胞(VSMC)增殖和迁移是AS形成及发展过程中重要的病理生理改变。流行病学资料表明,血脂水平高于正常与AS的发生及冠心病(CHD)的发病率有密切的相关性,从而明确高脂血症是AS及CHD的危险因素。许多学者认为,VEC结构和功能损伤是AS发生的始动环节,VSMC增殖和迁移是AS发生及发展的关键病理环节。人们在预防和治疗AS过程中,不仅要着眼于改善低密度脂蛋白(LDL)的氧…     

激活瞬时受体电位香草醛亚家族1改善平滑肌源性泡沫细胞形成机制研究

目的探讨瞬时受体电位香草醛亚家族1(TRPV1)在血管平滑肌细胞(VSMC)泡沫化过程中的作用及可能的机制。方法将野生型C57BL/6J雄性小鼠来源主动脉VSMC不加任何试剂刺激作为对照组,另将野生型C57BL/6J雄性小鼠和Toll样受体(TLR4)基因敲除(TLR4-/-)雄性小鼠来源主动脉VSMC使用氧化型低密度脂蛋白(oxLDL)80μg/ml刺激72h,建立oxLDL细胞模型,依次作为oxLDL组、辣椒素组(造模前预先用辣椒素50μmol/ml刺激VSMC 12h)和TLR4-/-组,每组5例。采用油红O染色观察VSMC内脂质聚积情况;检测VSMC内胆固醇、TRPV1、TLR4蛋白及炎性因子白细胞介素6(IL-6)和TNF-α表达。结果与对照组比较,oxLDL组VSMC泡沫化程度、胆固醇水平明显升高,TLR4及其介导的IL-6[(44.03±3.76)ng/L vs (25.64±4.84)ng/L]、TNF-α表达[(155.64±13.32)ng/L vs (89.86±9.18)ng/L]明显升高,差异有统计学意义(P<0.05),而TLR4-/-组和辣椒素组VSMC泡沫化程度、胆固醇水平、TLR4及其介导的IL-6、TNF-α表达与对照组比较,差异无统计学意义(P>0.05);与oxLDL组比较,辣椒素组VSMC中TRPV1蛋白表达明显上调,同时伴随VSMC泡沫化程度、胆固醇水平、TLR4及其介导的IL-6、TNF-α表达明显下调,差异有统计学意义(P<0.05)。结论激活TRPV1可通过干扰TLR4介导的炎性反应抑制VSMC泡沫化。     

强直性脊柱炎和类风湿关节炎患者外周血单个核细胞中Toll样受体4基因的表达及临床意义

目的探讨Toll样受体4(TLR4)mRNA在强直性脊柱炎(AS)、类风湿关节炎(RA)患者以及健康个体外周血单个核细胞(PBMC)中的表达差异及其临床意义。方法应用实时荧光定量逆转录聚合酶链反应(RT-PCR)检测2006年3月至10月第二军医大学附属长征医院60例AS患者、20例RA患者及30例健康对照PBMC中TLR4 mRNA的表达水平;应用ESR自动化分析仪和特定蛋白电泳仪分别测定红细胞沉降率(ESR)和血浆C-反应蛋白(CRP)。结果AS和RA患者PBMCTLR4 mRNA的表达水平明显高于对照组,但两疾病组之间差异并无显著性意义;人类白细胞抗原(HLA-B27)阳性和阴性AS患者均显著高于健康对照组,且HLA-B27阳性AS患者显著高于RA组,但两组AS患者以及HLA-B27阴性AS与RA患者之间,TLR4 mRNA差异无显著性意义;在HLA-B27阳性AS患者中,TLR4 mRNA的表达与ESR及CRP呈显著相关性,但在HLA-B27阴性AS患者中则无这种相关性。在RA患者中,TLR4 mRNA与CRP呈显著相关性。结论AS和RA患者PBMCTLR4 mRNA的表达均上调,AS患者上调与HLA-B27阳性与否无关,但HLA-B27阳性AS患者比RA上调更明显,且HLA-B27抗原影响AS患者TLR4 mRNA与ESR及CRP的相关性。TLR4的异常表达可能在AS和RA的发生和发展中起作用。     

动脉粥样硬化的发生机制和中医药干预研究进展

综述由炎性信号通路介导的炎症反应在动脉粥样硬化(AS)的发生机制及中西医结合研究新进展。动脉粥样硬化的发生发展包括脂质浸润、炎性反应、氧化应激、血管平滑肌细胞(VSMC)激活等。酪氨酸激酶/信号转导子和转录激活(JAK/STAT)信号通路、核因子-κB(NF-κB)信号通路及Wnt信号通路等通过炎症因子介导的炎症反应参与AS形成。中医药主要通过干预炎性信号通路、氧化应激而发挥抗AS,临床效果显著。     

辛伐他汀通过抑制TLR4信号通路调节血管平滑肌细胞炎症因子的表达

目的通过检测血管平滑肌细胞（VSMC）炎症因子白细胞介素6（IL-6）和肿瘤坏死因子α（TNF-α）及相关炎症信号分子的表达,探讨辛伐他汀在氧化型低密度脂蛋白（ox-LDL）诱导VSMC炎症反应中的作用和机制。方法体外培养大鼠VSMC,经Toll样受体4（TLR4）阻断剂抗TLR4抗体及辛伐他汀预处理,使用ox-LDL进行干预,用逆转录聚合酶链反应检测TLR4mRNA的表达,通过酶联免疫吸附法检测细胞培养上清液中炎症因子IL-6及TNF-α的水平。结果ox-LDL可以增加VSMC对IL-6及TNF-α的表达,预先经TLR4阻断剂干预后,IL-6及TNF-α的表达明显下调,与未阻断剂组相比,差异皆有统计学意义（P<0.01）;不同浓度的辛伐他汀可以剂量依赖性的抑制TLR4mRNA的表达（P<0.01）,同时也可以剂量依赖性的抑制IL-6及TNF-α的表达（P<0.05）;预先经TLR4阻断剂干预后,辛伐他汀可以显著地抑制TLR4mRNA、IL-6及TNF-α的表达,与辛伐他汀组比较,差异有统计学意义（P<0.01）。结论辛伐他汀对ox-LDL诱导的VSMC炎症因子的表达具有抑制作用,可以通过抑制TLR4的表达,进而抑制ox-LDL-TLR4信号通路而发挥作用。     

老年冠心病患者血清脑利钠肽和超敏C反应蛋白水平及意义

冠心病病理变化是动脉粥样硬化(AS),AS发生发展过程中,炎症起重要促进作用。超敏C反应蛋白(hs-CRP)是急性时相蛋白,对炎症发展起关键的介导作用,在AS发生发展过程中高表达。脑利钠肽(BNP)主要来源于心房,其可能对     

Toll样受体4与动脉粥样硬化

动脉粥样硬化是一种慢性炎症疾病。Toll样受体家族(TLRs)识别抗原相关的分子模式(PAMPs)后激发先天性免疫反应。TLR4不仅识别外源性配体脂多糖(LPS),也识别动脉损伤过程中表达的内源性配体。越来越多的研究表明TLR4可能在动脉粥样硬化病变的发生和发展过程中发挥主要作用。现对近年有关TLR4在动脉粥样硬化中的作用的研究进展作一综述。此外,还将讨论对TLR4信号的可能干预措施。     

Enhanced expression of TLR4 in smooth muscle cells in human atherosclerotic coronary arteries

Toll-like receptors (TLRs) play an essential role in innate immunity as components of the primary defense system against microbial infections. It has become evident that TLRs are also involved in the pathogenesis of various cardiovascular diseases. However, the expression patterns of TLRs in the human coronary arteries of coronary artery disease (CAD) patients and the regulatory mechanisms of their expression remain unknown. The TLR4 expression patterns were invstigated by immunohistochemical analysis of coronary specimens obtained from autopsy cases or CAD patients by using directional coronary atherectomy. In atherosclerotic coronary arteries (n = 8), TLR4 immunoreactivity was colocalized with infiltrating inflammatory cells. Interestingly, vascular smooth muscle cells of atherosclerotic coronary arteries intensely expressed TLR4 even in the regions that had few inflammatory cells. In contrast, TLR4 expression was barely detected in the vascular smooth muscle cells of nonatherosclerotic coronary arteries (n = 4). Furthermore, intense expression of smooth muscle TLR4 was observed in the coronary arteries of CAD patients (n = 52). Stimulation with tumor necrosis factor α and angiotensin II increased the expression of TLR4 mRNA in cultured human vascular smooth muscle cells. Candesartan, an antagonist of the angiotensin II type 1 receptor (AT1), and N-acetylcystine inhibited angiotensin II-induced TLR4 mRNA expression in these cells. These findings suggest that the vascular smooth muscle cells of atherosclerotic coronary arteries may be activated to express TLR4. Furthermore, proinflammatory cytokines and oxidative stress in the inflammatory lesions might contribute to the enhanced expression of TLR4 in vascular smooth muscle cells of atherosclerotic arteries.     

Toll样受体与动脉粥样硬化

动脉粥样硬化是心脑血管疾病的病理基础,其发病机制备受关注但至今尚未阐明,包括天然免疫和获得性免疫在内的免疫机制在动脉粥样硬化中的作用不容忽视。Toll样受体是一类介导天然免疫的受体家族,近年来认为Toll样受体4与动脉粥样硬化的发生发展密切相关。现主要就Toll样受体的结构、分布及配体识别特点,特别是Toll样受体4与动脉粥样硬化的相关性研究作一综述。     

Unexpected protective role for Toll-like receptor 3 in the arterial wall

The critical role of Toll-like receptors (TLRs) in mammalian host defense has been extensively explored in recent years. The capacity of about 10 TLRs to recognize conserved patterns on many bacterial and viral pathogens is remarkable. With so few receptors, cross-reactivity with self-tissue components often occurs. Previous studies have frequently assigned detrimental roles to TLRs, in particular to TLR2 and TLR4, in immune and cardiovascular disease. Using human and murine systems, we have investigated the consequence of TLR3 signaling in vascular disease. We compared the responses of human atheroma-derived smooth muscle cells (AthSMC) and control aortic smooth muscle cells (AoSMC) to various TLR ligands. AthSMC exhibited a specific increase in TLR3 expression and TLR3-dependent functional responses. Intriguingly, exposure to dsRNA in vitro and in vivo induced increased expression of both pro- and anti-inflammatory genes in vascular cells and tissues. Therefore, we sought to assess the contribution of TLR3 signaling in vivo in mechanical and hypercholesterolemia-induced arterial injury. Surprisingly, neointima formation in a perivascular collar-induced injury model was reduced by the systemic administration of the dsRNA analog Poly(I:C) in a TLR3-dependent manner. Furthermore, genetic deletion of TLR3 dramatically enhanced the development of elastic lamina damage after collar-induced injury. Accordingly, deficiency of TLR3 accelerated the onset of atherosclerosis in hypercholesterolemic ApoE(-/-) mice. Collectively, our data describe a protective role for TLR signaling in the vessel wall.     

Role of Toll-like receptors 2 and 4 in the induction of cyclooxygenase-2 in vascular smooth muscle

Bacteria stimulate macrophages as part of normal host defense. However, when this response is not limited, vascular smooth muscle may also be activated to express "vasoactive" genes (e.g., cyclooxygenase), leading to vascular collapse and septic shock. In macrophages, Toll-like receptors (TLRs) 4 and 2 transduce responses to Gram-negative and Gram-positive bacteria, respectively. However, the role of these TLRs in sensing bacteria in vascular smooth muscle is unclear. To address this question, we have cultured vascular smooth muscle cells from mice deficient in TLR4 (TLR4(-/-) mice), mice deficient in TLR2 (TLR2(-/-) mice), or control mice. Cells cultured from control or TLR2(-/-) mice, but not from TLR4(-/-) mice, expressed cyclooxygenase-2 and released increasing levels of prostaglandin E(2) after stimulation with whole Escherichia coli bacteria; the combination of IL-1beta plus TNF-alpha induced cyclooxygenase-2 in cells cultured from all three groups of animals. By contrast, Staphylococcus aureus affected cyclooxygenase-2 expression in two distinct ways. First, S. aureus induced a transient inhibition of cyclooxygenase-2 expression, which was overcome with time, and increased protein expression was noted. The effects of S. aureus on cyclooxygenase-2 expression were TLR2- and not TLR4-dependent. Thus, we show that Gram-positive and Gram-negative bacteria induce cyclooxygenase-2 in vascular smooth muscle with differing temporal profiles but with appropriate TLR2-versus-TLR4 signaling. These data have important implications for our understanding of the innate immune response in vascular cells and how it may impact vascular disease.     

Telomerase Therapy to Reverse Cardiovascular Senescence

Cellular senescence of endothelial cells plays an important role in the development of vascular lesions that ultimately lead to an atherosclerotic plaque. This review focuses on the age-related changes of endothelial and vascular smooth muscle cells that contribute to vascular disease and discusses potential new targets that could rejuvenate the vascular system and thereby prevent or delay atherosclerosis.     

Inflammation and immune response in atherosclerosis

Atherosclerosis is an inflammatory disease with a significant autoimmune component. Studies using transgenic murine models have clarified that recruitment of mononuclear leukocytes through vascular leukocyte-adhesion molecules and chemokines, differentiation of monocytes to macrophages, and endocytosis through scavenger receptors all are of decisive importance for atherosclerosis in hypercholesterolemic mice. T and B cells modulate disease progression and lesion development is reduced in mice lacking adaptive immunity. In particular, local immune responses eliciting Th1 effector mechanisms appear to be proatherogenic, whereas protective immune responses can be induced by immunization with oxidized low-density lipoprotein. Thus, innate immunity is necessary for atherosclerosis, whereas adaptive immunity is an important modulator of disease development.     

Functions of cyclophilin A in atherosclerosis

Cyclophilin A (CypA) is a ubiquitously distributed protein present both in intracellular and extracellular spaces. In atherosclerosis, various cells, including endothelial cells, monocytes, vascular smooth muscle cells and platelets, secrete CypA in response to excessive levels of reactive oxygen species. Atherosclerosis, a complicated disease, is the result of the interplay of different risk factors. Researchers have found that CypA links many risk factors, including hyperlipidemia, hypertension and diabetes, to atherosclerosis that develop into a vicious cycle. Furthermore, most studies have shown that secreted CypA participates in the developmental process of atherosclerosis via many important intracellular mechanisms. CypA can cause injury to and apoptosis of endothelial cells, leading to dysfunction of the endothelium. CypA may also induce the activation and migration of leukocytes, producing proinflammatory cytokines that promote inflammation in blood vessels. In addition, CypA can promote the proliferation of monocytes/macrophages and vascular smooth muscle cells, leading to the formation of foam cells and the remodelling of the vascular wall. Studies investigating the roles of CypA in atherosclerosis may provide new direction for preventive and interventional treatment strategies in atherosclerosis.     

脂肪酸结合蛋白4在下肢动脉粥样硬化及介入术后再狭窄中的作用和机制

下肢动脉硬化闭塞症介入术后的主要难题是再狭窄。脂肪酸结合蛋白4(FABP4)主要由巨噬细胞分泌,促进巨噬细胞内脂质积聚,从而使巨噬细胞转化为泡沫细胞,造成动脉粥样硬化。在动脉粥样硬化闭塞介入术后,血管内皮细胞也能特异性分泌FABP4;FABP4作用于血管平滑肌细胞,使之增殖和迁移形成增生内膜,并促进炎症反应,造成介入术后再狭窄。提示FABP4可能是治疗动脉粥样硬化和介入术后再狭窄的一个重要靶点。本文简述FABP4的生物学特性与功能,并就其在动脉粥样硬化及介入术后再狭窄中的作用及机制进行综述。     

The role of T-lymphocyte subpopulations in acute myocardial infarction

T lymphocytes have the potential to affect atherosclerosis at different stages of the process. They play an active role in acute myocardial infarction (AMI) and myocardial damage, and may affect the clinical outcome of patients with coronary artery disease. CD40 ligand expression on T lymphocytes promotes the expression of matrix-degrading enzymes in vascular smooth muscle cells and may thus establish a new pathway of immune-mediated destabilization of the human atheroma. The major class of T lymphocytes present in atherosclerotic lesions is CD4+. CD4+ cells differentiate into Th1 and Th2 lineage in response to the local milieu of cytokines. Much of the emphasis in atherosclerosis research is focused on the role of Th1 type responses.     

TLR4 Asp299Gly polymorphism is not associated with coronary artery stenosis

Inflammation and innate immunity may play a role in the pathogenesis of atherosclerosis. The Asp299Gly polymorphism in the toll-like receptor 4 (TLR4) gene reduces responsiveness to lipopolysaccharide and has been associated with reduced incidence and slower progression of carotid atherosclerosis. We analyzed this polymorphism in relation to susceptibility to and severity of coronary artery disease. METHODS: 1400 participants (mean age: 63 years, 31% female) in the Southampton Atherosclerosis Study were genotyped for the TLR4 Asp299Gly polymorphism using the tetra-primer PCR method. RESULTS: There was no significant difference between the frequencies of the Asp/Gly or Gly/Gly genotypes combined, compared to the Asp/Asp genotype, in patients with 0, 1, 2 or 3 coronary arteries with >50% stenosis (chi2(3 d.f.)2=0.4, P=0.94). No associations were observed between genotype groups and cardiac risk factors (P>0.05). CONCLUSION: The findings of this study do not support the hypothesis that the TLR4 Asp299Gly polymorphism influences predisposition to and progression of coronary artery disease.