Azelnidipine, a new long-acting calcium-channel blocker, inhibits tumour necrosis factor-alpha-induced monocyte chemoattractant protein-1 expression in endothelial cells

Dihydropyridine-based calcium antagonists are among the most widely used drugs for the treatment of hypertension. Since azelnidipine is a highly lipid-soluble dihydropyridine-based calcium antagonist with high vascular affinity, it is conceivable that azelnidipine could play a protective role against atherosclerosis. The aim of this study was to determine whether azelnidipine could suppress the expression of monocyte chemoattractant protein-1, a principal chemokine which mediates the recruitment of monocytes to the vasculature, in tumour necrosis factor (TNF)-alpha-exposed human umbilical vein endothelial cells. TNF-alpha, at a concentration of 10 ng/ml, upregulated monocyte chemoattractant protein-1 mRNA levels about seven-fold. Azelnidipine, 10 nmol/l, was found to inhibit the TNF-alpha-induced upregulation of monocyte chemoattractant protein-1 mRNA levels in human umbilical vein endothelial cells significantly. Furthermore, azelnidipine suppressed TNF-alpha-induced monocyte chemoattractant protein-1 production by human umbilical vein endothelial cells. This study demonstrates a novel beneficial aspect of azelnidipine, whereby azelnidipine could play a protective role against atherosclerosis by suppressing monocyte chemoattractant protein-1 overexpression in endothelial cells.     

恒磁场对血管紧张素Ⅱ作用下人血管平滑肌细胞分泌与表达单核细胞趋化蛋白-1的影响

目的:观察不同强度恒磁场对血管紧张素Ⅱ(angiotensinⅡ,AngⅡ)作用下人血管平滑肌细胞(vascularsmoothmusclecells,VSMC)分泌与表达单核细胞趋化蛋白-1(monocytechemoattractantprotein-1,MCP-1)的影响。方法:采用体外培养第4～6代的人脐动脉VSMC,实验分为6组,即对照组、AngⅡ(1×10-6mol/L)组及AngⅡ+不同磁感应强度(1,5,10,50Gs)的恒磁场组。各组细胞于培养及恒磁场作用24h后收集标本,用酶联免疫吸附试验(enzyme-linkedimmunoadsordentassay,ELISA)检测MCP-1的分泌量,免疫细胞化学检测MCP-1的蛋白表达。结果:AngⅡ1×10-6mol/L刺激VSMC24h,MCP-1的分泌量显著增高(P<0.05);而1,5,10,50Gs恒磁场组细胞MCP-1的分泌量显著低于AngⅡ组(F=752.89,P<0.05)。AngⅡ1×10-6mol/L与VSMC孵育24h后,MCP-1的表达显著增加(P<0.05和对照组);而1,5,10,50Gs恒磁场组MCP-1的表达显著低于AngⅡ组(F=238.26,P<0.05)。结论:1～50Gs的恒磁场可拮抗AngⅡ的作用,抑制VSMC分泌与表达MCP-1。     

晚期氧化蛋白产物对血管平滑肌细胞单核细胞趋化蛋白-1表达的影响

目的研究晚期氧化蛋白产物对血管平滑肌细胞单核细胞趋化蛋白-1表达的影响。方法采用逆转录聚合酶链反应技术和酶联免疫吸附试验测定细胞中单核细胞趋化蛋白-1mRNA的表达量及蛋白的含量。观察晚期氧化蛋白产物对平滑肌细胞单核细胞趋化蛋白-1表达的影响。结果晚期氧化蛋白产物促进平滑肌细胞单核细胞趋化蛋白-1mRNA和蛋白表达的作用(P<0.01)。结论晚期氧化蛋白产物促进平滑肌细胞单核细胞趋化蛋白-1mRNA和蛋白表达可能是其致动脉粥样硬化机制之一。     

Receptor mechanisms underlying the modulation of lipopolysaccharide-induced nuclear factor-kappaB expression in vascular endothelial cells by cholecystokinin octapeptide]

OBJECTIVE: To elucidate the receptor mechanisms underlying the modulation of lipopolysaccharide (LPS)-induced nuclear factor-kappaB (NF-kappaB) expression in human umbilical vein endothelial cell line ECV-304 cells by cholecystokinin octapeptide (CCK-8). METHODS: Human umbilical vein endothelial cell line ECV-304 cells were stimulated with vehicle, LPS, CCK-8 (10(-9)-10(-7) mol/L), CCK receptor non-specific antagonist proglumide, CCK-A receptor (CCK-AR) specific antagonist CR-1409 or CCK-B receptor (CCK-BR) specific antagonist CR-2945 singularly or in combination. The NF-kappaB p65 protein level was determined by Western blot and immunocytochemistry technique. RESULTS: LPS resulted in an increase in the up-regulatory expression and nuclear translocation of NF-kappaB p65 protein in ECV-304 compared with vehicle stimulation. CCK-8 obviously inhibited LPS-induced the changes in NF-kappaB p65 protein in a dose-dependent manner. The inhibitory effects of CCK-8 on NF-kappaB p65 protein expression were attenuated by proglumide>CR-2945>CR-1409. CONCLUSION: CCK-AR and CCK-BR are involved in the mediation of CCK-8 inhibitive regulation for LPS-induced NF-kappaB protein expression in ECV-04 cells, whereas the effect of CCK-BR are more than that of CCK-R.     

Gabexate mesilate,a synthetic protease inhibitor,inhibits lipopolysaccharide-induced tumor necrosis factor-alpha production by inhibiting activation of both nuclear factor-kappaB and activator protein-1 in human monocytes

Gabexate mesilate, a synthetic protease inhibitor, was shown to be effective in treating patients with sepsis-associated disseminated intravascular coagulation in which tumor necrosis factor-alpha (TNF-alpha) plays a critical role. We demonstrated that gabexate mesilate reduced lipopolysaccharide (LPS)-induced tissue injury by inhibiting TNF-alpha production in rats. In the present study, we analyzed the mechanism(s) by which gabexate mesilate inhibits LPS-induced TNF-alpha production in human monocytes in vitro. Gabexate mesilate inhibited the production of TNF-alpha in monocytes stimulated with LPS. Gabexate mesilate inhibited both the binding of nuclear factor-kappaB (NF-kappaB) to target sites and the degradation of inhibitory kappaBalpha. Gabexate mesilate also inhibited both the binding of activator protein-1 (AP-1) to target sites and the activation of mitogen-activated protein kinase pathways. These observations strongly suggest that gabexate mesilate inhibited LPS-induced TNF-alpha production in human monocytes by inhibiting activation of both NF-kappaB and AP-1. Inhibition of TNF-alpha production by gabexate mesilate might explain at least partly its therapeutic effects in animals given LPS and those in patients with sepsis.     

血管平滑肌细胞功能调节中血管紧张素1型受体表达和生物学作用的变化

目的:探讨血管平滑肌细胞(vascularsmoothmusclecell,VSMC)转染表达血管紧张素II(angiotensinII,AngII)2型受体(angiotensinIItype2receptor,AT2R)后其1型受体(angiotensinIItype1receptor,AT1R)表达所受的影响。方法:用同源重组方法构建带AT2R基因的重组复制缺陷型腺病毒载体(AdCMV-AT2R),体外转染VSMC,分别用流式细胞仪检测AT1R、AT2R细胞转染表达率、用免疫组织化学法和免疫荧光法检测其膜表达、以反转录聚合酶链式反应法(RT-PCR)和蛋白印迹法检测其mRNA和蛋白表达。结果:AdCMV-AT2R转染后,随着转染表达时间延长,AT2R细胞表达率呈显著增加趋势,48h最高表达率达89.51%,AngII作用与否及不同浓度AngII作用对AT2R表达无显著影响。而转染前后AT1R表达相对较稳定,受不同浓度AngII作用,其表达明显呈增加趋势。AT2R峰值表达时,免疫组织化学法和免疫荧光法检测其膜表达结果也提示AT2R表达随转染表达时间延长显著增加,转染前后AT1R表达无明显变化,在一定浓度范围内,AngII刺激对AT2R表达无显著影响,却显著增加AT1R的膜表达。RT-PCR法和蛋白印迹法检测AT1R和AT2R的mRNA和蛋白表达结果与其细胞表达率和膜表达的检测结果相一致。结论:AT2R转染表达并发挥其生物学作用时,对AT1R的表达无明显影响,VSMC转染表达AT2R后,     

Angiotensin II induces plasminogen activator inhibitor-1 and -2 expression in vascular endothelial and smooth muscle cells.

Angiotensin II (AII)- and Arg8-vasopressin (AVP)-regulated gene expression in vascular cells has been reported to contribute to vascular homeostasis and hypertrophy. In this report, AVP-induced expression of plasminogen activator inhibitor (PAI)-2 mRNA in rat microvessel endothelial (RME) cells was identified using differential mRNA display. Further characterization of vasoactive peptide effects on PAI expression revealed that AII stimulated a 44.8 +/- 25.2-fold and a 12.4 +/- 3.2-fold increase in PAI-2 mRNA in RME cells and rat aortic smooth muscle cells (RASMC), respectively. AII also stimulated a 10- and 48-fold increase in PAI-1 mRNA in RME cells and RASMC, respectively. These AII effects were inhibited by either Sar1, Ile8-angiotensin or the AT1 antagonist DuP 735, but were not significantly altered in the presence of the AT2 antagonist PD123319. AII stimulation of RASMC and RME cells also significantly increased both PAI-1 protein and PAI activity released to the culture medium. Inhibition of protein kinase C completely blocked PMA-stimulated induction of PAI-2 mRNA in both cell types and inhibited the AII-stimulated increase in RASMC by 98.6 +/- 2.8%. In contrast, protein kinase C inhibition only partially decreased the AII-stimulated PAI-2 expression in RME cells by 68.8 +/- 11.1%, suggesting that a protein kinase C-independent mechanism contributes to a 6.9 +/- 1.5-fold AII induction of PAI-2 expression in endothelial cells. AII and PMA also stimulated protein tyrosine phosphorylation in RME cells, and the tyrosine kinase inhibitor genistein partially blocked their induction of PAI-2 mRNA. These findings suggest that AII may regulate plasminogen activation in the vasculature by inducing both PAI-1 and PAI-2 expression.     

黄芪多糖对脂多糖诱导人THP21单核细胞MCP-1与IL-6表达的影响

目的通过研究黄芪多糖（astragalus polysaccharide,APS）对脂多糖（lipopolysaccharide,LPS）诱导人单核细胞株TI-IP21细胞趋化蛋白1（monocyte chemoattractant protein1,MCP-1）及白介素6（imerleukin．6,IL-6）的表达影响,探讨炎症状态下APS对单核细胞炎症因子表达的调控。方法体外培养人单核细胞THP21,以脂多糖刺激建立炎症细胞模型。以MTT法检测黄芪多糖对细胞的毒性,以荧光定量RT-PCR法检测黄芪多糖对THP21细胞MCP-1与IL-6mRNA水平表达的影响,以ELISA法检测黄芪多糖对THP21细胞MCP-1与IL-6细胞外分泌的影响。结果黄芪多糖在50、100、200μg／mL浓度下对THP21细胞均无明显毒性,100μg／mL的黄芪多糖明显抑制LPS诱导THP21细胞MCP-1与IL-6mRNA表达的增加及培养上清中MCP—1与IL-6的增加。结论黄芪多糖抑制脂多糖诱导的人单核细胞株THP21中MCP-1与IL-6的表达及分泌。     

Curcumin sensitizes prostate cancer cells to tumor necrosis factor-related apoptosis-inducing ligand/Apo2L by inhibiting nuclear factor-kappaB through suppression of IkappaBalpha phosphorylation

Epidemiologic studies suggest that diet rich in plant-derived foods plays an important role in the prevention of prostate cancer. Curcumin, the yellow pigment in the spice turmeric, has been shown to exhibit chemopreventive and growth inhibitory activities against multiple tumor cell lines. We have shown previously that curcumin and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)/Apo2L interact to induce cytotoxicity in the LNCaP prostate cancer cell line. In this study, we investigated the mechanism by which curcumin augments TRAIL-induced cytotoxicity in LNCaP cells. Subtoxic concentrations of the curcumin-TRAIL combination induced strong apoptotic response in LNCaP cells as demonstrated by the binding of Annexin V-FITC and cleavage of procaspase-3. Furthermore, LNCaP cells express constitutively active nuclear factor-kappaB (NF-kappaB), which is inhibited by curcumin. Because NF-kappaB has been shown to mediate resistance to TRAIL-induced apoptosis in tumor cells, we investigated whether there is a relationship between NF-kappaB activation and resistance to TRAIL in LNCaP prostate cancer cells. Pretreatment with curcumin inhibited the activation of NF-kappaB and sensitized LNCaP cells to TRAIL. A similar increase in the sensitivity of LNCaP cells to TRAIL-induced apoptosis was observed following inhibition of NF-kappaB by dominant negative mutant IkappaBalpha, an inhibitor of NF-kappaB. Finally, curcumin was found to inhibit NF-kappaB by blocking phosphorylation of IkappaBalpha. We conclude that NF-kappaB mediates resistance of LNCaP cells to TRAIL and that curcumin enhances the sensitivity of these tumor cells to TRAIL by inhibiting NF-kappaB activation by blocking phosphorylation of IkappaBalpha and its degradation.     

高血压合并冠心病患者平滑肌细胞内Ca2+水平和血管紧张素Ⅱ1型受体表达的观察研究

目的 观察高血压合并冠心病患者与正常血压冠心病患者平滑肌细胞内Ca2+水平和血管紧张素Ⅱ1型(AT1)受体的表达情况.方法 ①收集首都医科大学附属北京安贞医院心脏外科行冠状动脉旁路移植术患者术中剩余大隐静脉,进行细胞培养,分为高血压搭桥组和正常血压搭桥组.②用激光共聚焦显微镜(CLSM)观察不同浓度的血管紧张素Ⅱ(AngⅡ)分别刺激后2组的平滑肌细胞内游离钙浓度的变化情况.③提取培养的平滑肌细胞总RNA、RT-PCR,观察2组AT1受体的表达情况.结果 经AngⅡ刺激后人平滑肌细胞内Ca2+均迅速升高.在高血压搭桥组AngⅡ刺激后平滑肌细胞胞内Ca2+荧光吸光度较正常血压搭桥组明显升高(P＜0.05).在平滑肌细胞观察到高血压搭桥组AT1受体表达较正常血压搭桥组略高,差异有统计学意义(P＜0.05).结论 AngⅡ刺激后人血管平滑肌细胞存在胞内Ca2+的变化.高血压冠心病患者和正常血压冠心病患者平滑肌细胞存在AT1受体表达差别.     

Activation of the adenosine A3 receptor in RAW 264.7 cells inhibits lipopolysaccharide-stimulated tumor necrosis factor-alpha release by reducing calcium-dependent activation of nuclear factor-kappaB and extracellular signal-regulated kinase 1/2

Bacterial lipopolysaccharide (LPS) activates the immune system and promotes inflammation via Toll-like receptor (TLR) 4, which regulates the synthesis and release of tumor necrosis factor (TNF)-alpha and other inflammatory cytokines. Previous studies have shown that the nucleoside adenosine suppresses LPS-stimulated TNF-alpha release in human UB939 macrophages by activating an adenosine A(3) receptor (A(3)AR) subtype on these cells. In this study, we examined the mechanism(s) underlying A(3)AR-dependent inhibition of TNF-alpha release in a mouse (RAW 264.7) cell line. Treatment of RAW 264.7 cells with LPS (3 mug/ml) increased TNF-alpha release, which was reduced in a dose-dependent manner by adenosine analogs N(6)-(3-iodobenzyl)-adenosine-5'-N-methyluronamide (IB-MECA) and R-phenylisopropyladenosine and reversed by selective A(3)AR blockade. The increase in TNF-alpha release was preceded by an increase in intracellular Ca(2+) levels. Inhibition of intracellular Ca(2+) release by IB-MECA, a selective agonist of the A(3)AR, or with BAPTA-AM, an intracellular Ca(2+) chelator, reduced LPS-stimulated TNF-alpha release. Activation of the A(3)AR or inhibition of intracellular Ca(2+) release also reduced LPS-stimulated nuclear factor-kappaB (NF-kappaB) activation and extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation. Similar inhibition by A(3)AR was observed for LPS-stimulated inducible nitric-oxide synthase. These data support the contention that inhibition of LPS-stimulated release of inflammatory molecules, such as TNF-alpha and NO via the A(3)AR, involves suppression of intracellular Ca(2+)signaling, leading to suppression of NF-kappaB and ERK1/2 pathways.     

Telmisartan, an angiotensin II type 1 receptor blocker, inhibits advanced glycation end-product (AGE)-induced monocyte chemoattractant protein-1 expression in mesangial cells through downregulation of receptor for AGEs via peroxisome proliferator-activated receptor-gamma activation

Interaction between advanced glycation end-products (AGEs) and their receptor (RAGE) plays a central role in diabetic nephropathy pathogenesis. Pathophysiological crosstalk between the AGEs-RAGE system and angiotensin II (Ang II) is also involved in this disease. This study investigated the role of proliferator-activated receptor-gamma (PPAR-gamma)-modulating activity on inhibition of monocyte chemoattractant protein (MCP-1) expression. Telmisartan, an Ang II type 1 receptor blocker, downregulated RAGE mRNA and inhibited superoxide generation and MCP-1 gene expression in mesangial cells; these processes were blocked by GW9662, a PPAR-gamma inhibitor. Candesartan, an Ang II type 1 receptor blocker, did not suppress AGEs-induced superoxide generation. Telmisartan and the antioxidant, N-acetylcysteine, completely inhibited AGEs-induced MCP-1 overproduction by mesangial cells. These results suggest that telmisartan inhibits AGEs-signalling to MCP-1 expression in mesangial cells by downregulating RAGE gene expression and subsequent oxidative stress generation via PPAR-gamma activation. This study has demonstrated a unique benefit of telmisartan in that it may function as an anti-inflammatory agent against AGEs via PPAR-gamma activation and may play a protective role in diabetic nephropathy.     

Regulation of murine type 1 plasminogen activator inhibitor gene expression in vivo. Tissue specificity and induction by lipopolysaccharide, tumor necrosis factor-alpha, and transforming growth factor-beta.

The regulation of type 1 plasminogen activator inhibitor (PAI-1) gene expression was studied in vivo employing a murine model system. Nuclease protection analysis revealed relatively high concentrations of PAI-1 mRNA in the aorta, adipose tissue, heart, and lungs of untreated CB6 (BalbC X C57B16) mice. Treatment of CB6 mice with LPS, TNF-alpha, or transforming growth factor-beta (TGF-beta) increased the steady-state levels of PAI-1 mRNA within 3 h in all tissues examined. However, the greatest responses to TGF-beta were observed in adipose tissue and the kidney, while LPS and TNF-alpha strongly stimulated PAI-1 gene expression in the liver, kidney, lung, and adrenals. In C3H/HeJ mice, which exhibit defective TNF-alpha release in response to LPS, the response of the PAI-1 gene to LPS was severely attenuated. However, injection of these mice with TNF-alpha increased PAI-1 mRNA in a tissue-specific pattern strikingly similar to that observed in LPS-treated CB6 mice. These results demonstrate that the PAI-1 gene is regulated in a complex and tissue-specific manner in vivo, and suggest a role for TNF-alpha in the response of the PAI-1 gene to sepsis.     

早期应用生长反应因子1小干扰RNA可抑制烟草烟雾刺激大鼠主动脉平滑肌细胞白细胞介素1β mRNA的表达

背景：研究表明,在动脉粥样硬化的血管壁细胞中白细胞介素1β表达水平升高。目的：观察早期生长反应因子1的小干扰RNA对烟草烟雾提取物刺激大鼠主动脉平滑肌细胞中白细胞介素1β mRNA表达的影响。方法：体外培养大鼠主动脉平滑肌细胞,用不同体积分数（0%,5%,10%,20%和40%）烟草烟雾提取物刺激细胞,筛选最佳体积分数烟草烟雾提取物干预细胞0,8,16和24h,以确定最佳干预时间,最后用生长反应因子1小干扰RNA以沉默细胞中生长反应因子1的表达。结果与结论：RT-PCR结果显示,烟草烟雾提取物可诱导大鼠主动脉平滑肌细胞白细胞介素1β mRNA的表达,且有时间和浓度依赖性,烟草烟雾提取物最佳干预时间为8h,最佳干预体积分数为10%。将生长反应因子1小干扰RNA转染10%烟草烟雾提取物刺激的细胞后8h,白细胞介素1β mRNA表达明显减少（P〈0.05）。证实早期应用生长反应因子1小干扰RNA可以抑制烟草烟雾提取物诱导的大鼠主动脉平滑肌细胞中白细胞介素1β mRNA的表达。     

早期应用生长反应因子1小干扰RNA可抑制烟草烟雾刺激大鼠主动脉平滑肌细胞白细胞介素1β mRNA的表达

背景:研究表明,在动脉粥样硬化的血管壁细胞中白细胞介素1β表达水平升高。目的:观察早期生长反应因子1的小干扰RNA对烟草烟雾提取物刺激大鼠主动脉平滑肌细胞中白细胞介素1β mRNA表达的影响。方法:体外培养大鼠主动脉平滑肌细胞,用不同体积分数(0%,5%,10%,20%和40%)烟草烟雾提取物刺激细胞,筛选最佳体积分数烟草烟雾提取物干预细胞0,8,16和24h,以确定最佳干预时间,最后用生长反应因子1小干扰RNA以沉默细胞中生长反应因子1的表达。结果与结论:RT-PCR结果显示,烟草烟雾提取物可诱导大鼠主动脉平滑肌细胞白细胞介素1β mRNA的表达,且有时间和浓度依赖性,烟草烟雾提取物最佳干预时间为8h,最佳干预体积分数为10%。将生长反应因子1小干扰RNA转染10%烟草烟雾提取物刺激的细胞后8h,白细胞介素1β mRNA表达明显减少(P<0.05)。证实早期应用生长反应因子1小干扰RNA可以抑制烟草烟雾提取物诱导的大鼠主动脉平滑肌细胞中白细胞介素1β mRNA的表达。