Atorvastatin neutralizes the up-regulation of thrombospondin-1 induced by thrombin in human umbilical vein endothelial cells.

Statins have been reported to affect blood vessel formation. Thrombospondin-1 (TSP-1) is a multifunctional protein that affects vasculature systems such as platelet activation, angiogenesis, and wound healing. This study was designed to investigate the effect of atorvastatin on TSP-1 synthesis in thrombin-stimulated human umbilical vein endothelial cells (HUVECs), and its regulation by mevalonate or its derivatives. The results showed that atorvastatin down-regulated TSP-1 expression in HUVECs. This effect was fully reversed by mevalonate, farnesylpyrophosphate (FPP), and gerarylgeranylpyrophosphate (GGPP). Furthermore, farnesyltransferase and geranylgeranyltransferase inhibitors decreased TSP-1expression. It was also found that thrombin increased TSP-1 expression in HUVECs. Atorvastatin (0.1, 1, and 10 muM) decreased TSP-1 in thrombin-stimulated cells (45%, 66%, and 80%). Mevalonate partially reversed this inhibitory effect of atorvastatin on TSP-1, whereas the presence of FPP and GGPP did not alter TSP-1. Rho-kinase inhibitor neutralized the up-regulation of TSP-1 induced by thrombin. In conclusion, atorvastatin inhibits TSP-1 expression in endothelial cells via the mevalonate pathway. Rho protein activation is necessary for up-regulation of TSP-1 synthesis induced by thrombin. Because FPP and GGPP are essential for the activity of Rho proteins, inhibition of these proteins may constitute the mechanism by which atorvastatin inhibits thrombin up-regulated TSP-1 expression.     

阿托伐他汀抑制ox-LDL诱导的人脐静脉内皮细胞表达胸腺基质淋巴细胞生成素TSLP的表达

目的:观察阿托伐他汀对ox-LDL诱导人脐静脉内皮细胞(HUVECs)表达胸腺基质淋巴细胞生成素(TSLP)的影响。方法:将HUVECs分为3组,对照组加50 mg/L的ox-LDL培养12小时;实验组分为2组,分别加50 mg/L的ox-LDL和不同浓度的阿托伐他汀培养12小时,于6小时和12小时进行检测,用ELISA法检测细胞培养上清液中TSLP的浓度,用RT-PCR检测TSLP mRNA的表达,采用免疫荧光检测细胞胞浆中TSLP表达。结果:ELISA和IF结果显示,实验组上清液和细胞浆内的TSLP的表达明显低于对照组,并随浓度的增大及时间的延长,TSLP降低得更明显。结论:阿托伐他汀可抑制ox-LDL诱导的HUVECs表达TSLP,这可能是阿托伐他汀抗动脉粥样硬化炎症反应的机制之一。     

TLR4激动对内皮细胞粘附功能的影响及阿托伐他汀的干预研究

目的：观察Toll样受体4（TLR4）激动对脐静脉内皮细胞（HUVECs）氧化低密度脂蛋白受体LOX-1的调节和对单核细胞与HUVECs粘附率的影响，以及LOX-1在内皮细胞粘附功能中的作用，并观察阿托伐他汀的干预作用方法：RT-PCR方法检测TLR4、LOX-1 mRNA表达水平，流式细胞术检测TLR4、LOX-1蛋白表达水平，细胞计数法计算单核细胞与HUVECs粘附率。结果：脂多糖(1 mg/L) 孵育24 h上调HUVECs TLR4、LOX-1 mRNA和蛋白的表达，增加单核细胞与HUVECs粘附率,抗LOX-1抗体部分抑制LPS介导的单核细胞与HUVECs粘附率的增加，阿托伐他汀（10 μmol/L）抑制脂多糖介导的上述效应。结论：TLR4激动上调LOX-1表达及增加内皮细胞粘附功能，LOX-1在LPS介导的单核内皮细胞粘附功能中起部分作用，阿托伐他汀可能通过抑制TLR4表达及TLR4 介导的LOX-1表达而发挥其内皮细胞保护作用。     

The effects of atorvastatin on gluten-induced intestinal T cell responses in coeliac disease

Various experimental models suggest that the cholesterol-lowering drugs statins may also modulate immune responses. Cellular level studies on human disorders are needed, however, to provide a rational basis for clinical testing of statins as immune therapy. Coeliac disease, a chronic small intestinal inflammation driven by HLA-DQ2 restricted mucosal T cells that are specific for ingested wheat gluten peptides, is in many ways ideal for this purpose. In addition, there is a need for alternative treatment to the gluten-free diet in this disorder. Here we have assessed the effects of atorvastatin on gluten-reactive T cells, dendritic cells and the coeliac mucosa by in vitro culture of biopsies. Atorvastatin inhibited gluten-induced proliferation and specific cytokine production of human intestinal gluten-reactive T cell clones and lines. Dendritic cells exposed to atorvastatin displayed a reduced expression of the costimulatory molecule CD83 upon maturation with lipopolysaccharide. Incubation of intestinal biopsy specimens with atorvastatin in vitro, however, did not influence gluten-induced cytokine release. In conclusion, atorvastatin has specific effects on isolated gluten-reactive T cells and dendritic cells, but does not shut down the gluten-induced production of proinflammatory cytokines in intestinal biopsies.     

Bovine lactoferricin inhibits basic fibroblast growth factor- and vascular endothelial growth factor165-induced angiogenesis by competing for heparin-like binding sites on endothelial cells

Angiogenesis is a complex process whereby new blood vessels form from pre-existing vasculature in response to proangiogenic factors such as basic fibroblast growth factor (bFGF) and the 165-kd isoform of vascular endothelial growth factor (VEGF165). Angiogenesis inhibitors show considerable potential in the treatment of cancer because angiogenesis is necessary for tumor growth beyond a few millimeters in diameter because of the tumor's need for oxygen and nutrient supply, as well as waste removal. Bovine lactoferricin (LfcinB) is a peptide fragment of iron- and heparin-binding lactoferrin obtained from cow's milk. Here we provide in vivo and in vitro evidence that LfcinB has potent antiangiogenic activity. LfcinB strongly inhibited both bFGF- and VEGF165-induced angiogenesis in Matrigel plugs implanted in C57BL/6 mice. In addition, LfcinB inhibited the in vitro proliferation and migration of human umbilical vein endothelial cells (HUVECs) in response to bFGF or VEGF165 but was not cytotoxic to HUVECs. Rather, LfcinB complexed with heparin-like structures on the HUVEC surface that are involved in the binding of bFGF and VEGF165 to their respective receptors, thereby preventing receptor-stimulated angiogenesis. These findings suggest that LfcinB may have utility as an antiangiogenic agent for the treatment of human cancers.     

The role of atorvastatin in regulating the immune response leading to vascular damage in a model of Kawasaki disease

Superantigens have been implicated in a number of diseases including Kawasaki disease (KD), a multi-system vasculitis resulting in coronary artery aneurysms. We have characterized a murine disease model in which coronary arteritis is induced by a novel superantigen found in Lactobacillus casei cell wall extract (LCWE). Using this animal model of KD, we have identified three pathogenic steps leading to coronary artery aneurysm formation. These steps include T cell activation and proliferation, production of the proinflammatory cytokine tumour necrosis factor (TNF)-α and up-regulation of matrix metalloproteinase 9 (MMP-9), an elastolytic protease. In addition to their cholesterol-lowering effects, 3-hydroxy-3-methylglutaryl (HMG) coenzyme A (CoA) reductase inhibitors (statins) have pleotropic immunomodulatory properties. Thus, we examined the effect of atorvastatin in modulating each of these three critical pathogenic processes leading to aneurysm formation in the disease model. Atorvastatin inhibited lymphocyte proliferation in response to superantigen stimulation in a dose-dependent manner. This inhibition was also observed for production of soluble mediators of inflammation including interleukin (IL)-2 and TNF-α. The inhibitory effect on proliferation was rescued completely by mevalonic acid, confirming that the mechanism responsible for this inhibitory activity on immune activation was inhibition of HMG-CoA reductase. Similarly, TNF-α-induced MMP-9 production was reduced in a dose-dependent manner in response to atorvastatin. Inhibition of extracellular-regulated kinase (ERK) phosphorylation appears to be the mechanism responsible for inhibition of MMP-9 production. In conclusion, atorvastatin is able to inhibit critical steps known to be important in the development of coronary aneurysms, suggesting that statins may have therapeutic benefit in patients with KD.     

阿托伐他汀对脂多糖诱导人脐静脉内皮细胞Toll样受体4及其下游信号转导通路的影响

背景：研究表明Toll样受体4参与了动脉粥样硬化的发生和发展,目前Toll样受体4与MyD88依赖性或MyD88非依赖性信号转导通路在动脉粥样硬化发生和发展中的机制尚不明确。 目的：观察阿托伐他汀对脂多糖诱导的人脐静脉内皮细胞Toll样受体4及其下游信号转导通路主要元件MyD88、TRAF-6、TRAM及TRIF表达的影响,分析阿托伐他汀防治动脉粥样硬化的机制。 方法：体外培养人脐静脉内皮细胞,用脂多糖刺激并加入阿托伐他汀干预24 h,收集细胞,用荧光定量PCR方法测定TLR4、MyD88、TRAF-6、TRAM及TRIF mRNA表达;用Western blotting法测定TLR4、MyD88及TRAF-6蛋白表达。 结果与结论：用脂多糖刺激人脐静脉内皮细胞后,引起TLR4、MyD88、TRAF-6、TRAM和TRIF的高表达(P < 0.01),用阿托伐他汀干预后可显著抑制TLR4、MyD88及TRAF-6的表达(P < 0.01)。提示阿托伐他汀可阻断Toll样受体4高表达,同时阻断Toll样受体4胞内信号转导的MyD88依赖性途径,这可能是阿托伐他汀抗动脉粥样硬化的作用机制之一。     

阿托伐他汀通过抑制PKC的激活对抗高糖诱导的人脐静脉内皮细胞氧化应激反应

目的:探讨阿托伐他汀对高糖诱导的人脐静脉血管内皮细胞(HUVECs)产生氧化应激的影响及其作用机制。方法:体外培养HUVECs,以25 mmol/L葡萄糖干预,模拟糖尿病患者体内环境,通过流式细胞术和共聚焦显微镜检测细胞内的活性氧(ROS)水平,采用Lucigenin分析方法测定还原型烟酰胺腺嘌呤二核苷酸磷酸(NADPH)氧化酶活性,分别应用实时荧光定量PCR和免疫印迹杂交的方法检测 NADPH氧化酶亚基Nox4和Nox2/gp91^phox的表达水平,用免疫印迹杂交方法检测蛋白激酶C(PKC)蛋白的磷酸化水平。结果:(1)在高糖环境(终浓度为25 mmol/L)下,HUVECs内ROS生成显著增加,NADPH氧化酶的活性显著增强,NADPH 氧化酶Nox4和Nox2/gp91^phox亚基的mRNA和蛋白表达水平显著上调;(2)阿托伐他汀可显著抑制高糖诱导的ROS 生成、NADPH氧化酶活性的增强及NADPH 氧化酶Nox4和Nox2/gp91^phox亚基表达水平的增加幅度,且具有浓度依赖性;(3)PKC抑制剂(PKC inhibitor peptide, 20 μmol/L)可显著抑制高糖环境下ROS的生成、NADPH氧化酶活性的增强及NADPH 氧化酶Nox4和Nox2/gp91^phox亚基表达水平的增加幅度;(4)阿托伐他汀可抑制高糖诱导的PKC蛋白的磷酸化。结论:PKC的活化参与了高糖诱导的HUVECs产生的氧化应激反应。阿托伐他汀通过抑制PKC蛋白的活化对抗高糖诱导的内皮细胞产生的氧化应激反应。     

Inhibitors of differentiation/DNA binding proteins Id1 and Id3 are regulated by statins in endothelial cells.

Id proteins (inhibitors of differentiation), which are involved in the control of cell cycle progression, can delay cellular differentiation and senescence and have been implicated in angiogenesis. The regulation of Id proteins in endothelial cells (ECs) by proangiogenic statins has not been investigated yet and remains unresolved. In this study, human dermal microvascular ECs (HDMECs) were stimulated with fluvastatin, vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and serum in vitro. The regulation of Id1, Id3, p21, p27, and p53 and the phosphorylation of AKT was investigated by Western blotting. Id1 was up-regulated by fluvastatin and serum, but not by VEGF and HGF. Fluvastatin did not regulate p21 and p27, but down-regulated Id3 and p53 slightly. In contrast to VEGF and HGF, fluvastatin did not result in AKT phosphorylation, indicating that this pathway is not involved in the control of endothelial Id1 expression. These experiments demonstrate for the first time that Id1 can be up-regulated and p53 down-regulated by a statin in HDMECs. Regulation of these proteins in ECs may account for the proangiogenic effect of statins.     

Down-modulation of monocyte transendothelial migration and endothelial adhesion molecule expression by fibroblast growth factor: reversal by the anti-angiogenic agent SU6668

Basic and acidic fibroblast growth factor (bFGF and aFGF, respectively) and vascular endothelial growth factor (VEGF) exert angiogenic actions and have a role in wound healing, inflammation, and tumor growth. Monocytes and endothelial cells are involved in these processes, but the effect of FGF and VEGF on monocyte-endothelial cell interactions has not been defined. We observed that monocyte adhesion to resting or cytokine (tumor necrosis factor-alpha or interleukin-1 alpha)-stimulated human umbilical vein endothelial cells (HUVECs) was markedly inhibited (40 to 65%) by culture (1 to 6 days) of HUVECs with aFGF or bFGF. Monocyte transendothelial migration induced by C5a and chemokines (MCP-1, SDF-1 alpha, RANTES, MIP-1 alpha) was also suppressed (by 50 to 75%) on bFGF-stimulated HUVECs. VEGF did not have these effects at the concentrations used (10 to 20 ng/ml), although like bFGF, it promoted HUVEC proliferation. Culture of HUVECs with bFGF and aFGF significantly down-regulated intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin expression on resting or tumor necrosis factor-alpha-stimulated HUVECs, but had no influence on platelet endothelial cell adhesion molecule (PECAM)-1 and VE-cadherin expression. bFGF also inhibited MCP-1 production by HUVECs. The inhibitory effects of bFGF on monocyte transendothelial migration and adhesion molecule expression were reversed by SU6668, an anti-angiogenic agent and bFGF receptor tyrosine kinase inhibitor. Our results suggest that bFGF and aFGF may suppress endothelial-dependent monocyte recruitment and thus have an anti-inflammatory action during angiogenesis in chronic inflammation but inhibit the immunoinflammatory tumor defense mechanism. However, SU6668 is an effective agent to prevent this down-regulatory action of bFGF on monocyte-endothelial cell interactions.     

Vascular Endothelial Growth Factor Receptor-1 Modulates Vascular Endothelial Growth Factor-Mediated Angiogenesis via Nitric Oxide

The known responses of vascular endothelial growth factor (VEGF) are mediated through VEGF receptor-2 (VEGFR-2/KDR) in endothelial cells. However, it is unknown whether VEGFR-1 (Flt-1) is an inert decoy or a signaling receptor for VEGF during physiological or pathological angiogenesis. Here we report that VEGF-stimulated nitric oxide (NO) release is inhibited by blockade of VEGFR-1 and that VEGFR-1 via NO negatively regulates of VEGFR-2-mediated proliferation and promotes formation of capillary networks in human umbilical vein endothelial cells (HUVECs). Inhibition of VEGFR-1 in a murine Matrigel angiogenesis assay induced large aneurysm-like structures. VEGF-induced capillary growth over 14 days was inhibited by anti-VEGFR-2-blocking antibody as determined by reduced tube length between capillary connections (P < 0.0001) in an in vitro angiogenesis assay. In contrast, loss of VEGFR-1 activity with a neutralizing anti-VEGFR-1 antibody resulted in an increase in the accumulation of endothelial cells (P < 0.0001) and a dramatic decrease in the number of capillary connections that were restored by the addition of NO donor. Porcine aortic endothelial (PAE) cells expressing human VEGFR-1 but not VEGFR-2 plated on growth factor-reduced Matrigel rearranged into tube-like structures that were prevented by anti-VEGFR-1 antibody or a cGMP inhibitor. VEGF stimulated NO release from VEGFR-1- but not VEGFR-2-transfected endothelial cells and placenta growth factor-1 stimulated NO release in HUVECs. Blockade of VEGFR-1 increased VEGF-mediated HUVEC proliferation that was inhibited by NO donors, and potentiated by NO synthase inhibitors. These data indicate that VEGFR-1 is a signaling receptor that promotes endothelial cell differentiation into vascular tubes, in part by limiting VEGFR-2-mediated endothelial cell proliferation via NO, which seems to be a molecular switch for endothelial cell differentiation.     

Evidence for the involvement of SDF-1 and CXCR4 in the disruption of endothelial cell-branching morphogenesis and angiogenesis by TNF-alpha and IFN-gamma

Vigorous inflammatory responses are associated with tissue damage, particularly when toxic levels of inflammatory cytokines are produced. Despite proangiogenic factors being present early at sites of inflammation, vascular repair occurs toward the end of the inflammatory response, suggesting modulation of the proangiogenic response. Endogenous inhibitors of angiogenesis induced during acute inflammation are poorly characterized. Here, we looked for endothelial cell-derived modulators of angiogenesis that may account for delayed neovascularization during inflammation. Gene profiling of endothelial cells showed that the inflammatory cytokines tumor necrosis factor alpha (TNF-alpha) and interferon-gamma (IFN-gamma) selectively promote expression of the antiangiogenic molecules, IFN-inducible protein-10, monokine induced by IFN-gamma, tryptophanyl-tRNA synthetase, and tissue inhibitor of metalmetalloproteinase-1, and inhibit expression of the proangiogenic molecules, platelet-endothelial cell adhesion molecule-1, vascular endothelial growth factor receptor-2, stromal cell-derived factor-1 (SDF-1), collagen type IV, endothelial cell growth factor-1, and carcinoembryonic antigen-related cell adhesion molecule-1. Reduced endothelial cell expression of SDF-1 protein by TNF-alpha and IFN-gamma disrupts extracellular matrix-dependent endothelial cell tube formation, an in vitro morphogenic process that recapitulates critical steps in angiogenesis. Replacement of SDF-1 onto the endothelial cell surface reconstitutes this morphogenic process. In vivo, TNF-alpha and IFN-gamma inhibit growth factor-induced angiogenesis and SDF-1 expression in endothelial cells. These results demonstrate that SDF-1/CXC chemokine receptor-4 constitutes a TNF-alpha- and IFN-gamma-regulated signaling system that plays a critical role in mediating angiogenesis inhibition by these inflammatory cytokines.     

阿托伐他汀对TNF-α和IL-1β诱导的大鼠主动脉内皮细胞PAPP-A表达的影响

目的: 研究阿托伐他汀对炎症因子肿瘤坏死因子 α(TNF-α)和白细胞介素-1β(IL-1β)诱导大鼠主动脉内皮细胞表达妊娠相关血浆蛋白A(PAPP-A)的影响。方法: 原代培养大鼠主动脉内皮细胞,选择生长良好的第3-4代细胞用于实验。实验分组:(1)空白对照组 :不加干预措施原培养液继续培养;(2)阿托伐他汀浓度组:加入浓度分别为 0.1、1、10 μmol/L的阿托伐他汀作用24 h;(3)阿托伐他汀时间组:加入浓度为10 μmol/L的阿托伐他汀分别作用6、12、24 h;(4)阿托伐他汀干预组:加入TNF-α(60 μg/L)或者IL-1β(20 μg/L)作用1 h后,再加入不同浓度的阿托伐他汀(0.1、1、10 μmol/L)进行培养,分别于作用6、12、24 h终止实验。MTT法观察药物对细胞增殖的影响, RT-PCR技术测定细胞中PAPP-A mRNA的表达, ELISA方法检测上清液中PAPP-A蛋白水平。结果: (1) 外源性加入阿托伐他汀及TNF-α或者IL-1β后,分别作用3、6、12、24、48 h,同对照组相比,细胞增殖能力无明显变化(P<0.05),说明干预药物本身对细胞没有毒性作用。(2)单独加入阿托伐他汀,细胞PAPP-A表达水平与空白对照组比较没有明显差异(P<0.05)。(3)炎症因子作用一段时间后再加入阿托伐他汀,PAPP-A mRNA和蛋白表达水平随着阿托伐他汀浓度和作用时间的增加而逐渐降低,有一定的浓度-时间依赖关系,与 TNF-α组和IL-1β组比较明显下降(P<0.05)。结论: 阿托伐他汀本身对细胞表达PAPP-A没有影响,但在一定程度上抑制TNF-α和IL-1β诱导的内皮细胞PAPP-A的表达,并有浓度-时间依赖关系。     

低分子量肝素体外抗肿瘤血管新生作用

目的探讨低分子量肝素（low moleeular weight heparin,LMWH）对肿瘤血管新生的作用。方法采用四唑盐比色实验（MTT）及体外人前列腺癌高转移细胞（PC-3M）和人脐静脉内皮细胞（human umbilical vein endothelial cells,HUVECs）共孵育系统检测HUVECs增殖和小管形成。结果500mg／L LMWH能够显著抑制内皮细胞的增殖（P〈0．05）;PC-3M能够激活HUVECs,使细胞拉长、排列成管状结构;LMWH能够显著抑制PC-3M刺激的HUVECs小管形成,并呈剂量依赖性。结论LMWH具有体外抑制肿瘤血管新生的作用。     

阿托伐他汀通过下调NLRP1炎性体表达抑制IL-1β和IL-18的释放

 目的:探讨核苷酸结合寡聚化结构域样受体蛋白1(NLRP1)炎性体在阿托伐他汀抑制THP-1巨噬细胞白细胞介素-1β(IL-1β)和白细胞介素-18(IL-18)分泌中的作用。方法:用10 μg/L脂多糖诱导THP-1巨噬细胞分泌IL-1β和IL-18,以不同浓度阿托伐他汀(1、10和20 μmol/L)孵育细胞24 h,或以10 μmol/L阿托伐他汀处理细胞不同时间(12、24和48 h),或转染NLRP1 siRNA以沉默细胞内NLRP1的表达。采用RT-PCR检测细胞内NLRP1炎性体mRNA的表达,Western blot检测细胞内NLRP1炎性体蛋白的表达,ELISA检测细胞上清液中IL-1β和IL-18的含量。结果:阿托伐他汀可抑制THP-1巨噬细胞NLRP1炎性体mRNA和蛋白的表达,且这种效应呈浓度和时间依赖性。转染NLRP1 siRNA后,THP-1巨噬细胞NLRP1的蛋白表达明显下降,且阿托伐他汀对IL-1β和IL-18分泌的抑制作用明显增强。结论:阿托伐他汀通过抑制NLRP1炎性体表达减少巨噬细胞IL-1β和IL-18的释放,发挥抗炎作用,进而延缓动脉粥样硬化进展。     

Differential effects of statins on relevant functions of human monocyte-derived dendritic cells

Statins were shown to possess immunomodulating properties, but the mechanisms of statin effects on the immune system are poorly understood. We analyzed the influence of statins on professional antigen-presenting dendritic cells (DC). Immature DC were cultivated from monocytes of healthy donors. DC maturation was induced by lipopolysaccharide (LPS; 1 microg/mL). Unstimulated and LPS-stimulated DC were treated with simvastatin or atorvastatin (0.1-1 microM). The expression of CD40, CD83, CD86, and human leukocyte antigen-DR on unstimulated and LPS-stimulated DC was reduced significantly by statins, and the expression of Toll-like receptor 2 (TLR2) and TLR4 on LPS-stimulated DC was enhanced temporarily. Statins caused a significant reduction of endocytosis of fluorescein isothiocyanate-dextran by DC. Statins significantly inhibited the basal secretion of interleukin (IL)-6, IL-8, IL-12, and tumor necrosis factor alpha from unstimulated DC, and their release from LPS-stimulated DC was enhanced. In mixed leukocyte reaction, preincubation of LPS-stimulated DC with statins significantly suppressed their clustering with T cells and their ability to induce T cell proliferation, CD71, and CD25 up-regulation on T cells and the secretion of interferon-gamma and IL-2 from T cells. In conclusion, this study showed that statins suppressed endocytosis, basal secretion of proinflammatory cytokines, and the ability of DC to induce T cell proliferation, activation, and T helper cell type 1 differentiation. However, statin preincubation of LPS-stimulated DC caused a further increase in their secretion of proinflammatory cytokines.     

An involvement of SR-B1 mediated p38 MAPK signaling pathway in serum amyloid A-induced angiogenesis in rheumatoid arthritis

Serum amyloid A (SAA) has been reported high expression in autoimmune diseases, such as rheumatoid arthritis (RA). However, detailed molecular mechanisms induced by SAA in the pathogenesis of RA are still unclear. Herein, we focused on the role of SAA–SR-B1 mediated p38 MAPK signaling pathway in the process of RA angiogenesis. Our results showed that both SAA and SR-B1 predominantly localized to vascular endothelial cells, lining and sublining layers in RA synovium. In a series of in vitro experiments with human umbilical vein endothelial cells (HUVECs), SAA induced the endothelial cells (ECs) proliferation, migration and tube formation. However, blockage of SR-B1 and p38 MAPK inhibited SAA-induced cells proliferation, migration and tube formation. In conclusion, our data showed a possible molecular mechanism for SAA–SR-B1 induced angiogenesis events via p38 MAPK signaling pathway.     

Aliskiren抑制LPS诱导HUVECs新生血管的形成及可能机制

 目的: 研究阿利吉仑(aliskiren)对脂多糖(LPS)诱导人脐静脉内皮细胞(HUVECs)新生血管形成能力的影响及可能的机制。方法: 常规培养的HUVECs随机分为空白组和肾素组,ELISA法测定炎性细胞因子肿瘤坏死因子-α(TNF-α)和细胞间黏附分子-1(ICAM-1)水平,Western blot法检测Toll样受体4(TLR4)和ICAM-1的蛋白水平。将常规培养的HUVECs随机分为空白对照组、LPS模型组以及aliskiren低剂量(1μ mol/L)、中剂量(10μ mol/L)和高剂量(100μ mol/L)组。MTT法和BrdU法检测HUVECs的增殖能力,Transwell法测定HUVECs的迁移率,以HUVECs在Matrigel胶上形成管腔结构情况来判断其血管形成能力。ELISA测定炎性细胞因子TNF-α、ICAM-1和单核细胞趋化蛋白-1(MCP-1)的水平,RT-PCR和Western blot法检测肾素、TLR4、基质金属蛋白酶-2(MMP-2)和基质金属蛋白酶-9(MMP-9)的mRNA和蛋白水平。结果: 肾素能够刺激HUVECs炎症因子的分泌及TLR4的表达;aliskiren呈浓度依赖性抑制HUVECs增殖、迁移及新生血管形成,降低MCP-1、TNF-α、IL-6水平及肾素、MMP-2、MMP-9的表达,抑制TLR4表达(P<0.05)。结论: Aliskiren能够有效抑制LPS诱导HUVECs新生血管形成能力,可能与其下调肾素表达抑制TLR4途径介导的炎症反应及MMP-2、MMP-9生成有关。