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【目的】研究磷酸二酯酶4(PDE4)特异性抑制剂咯利普兰抑制中性粒细胞黏附的有关分子机制,明确其抗炎的主要信号通路,为PDE4选择性中药抑制剂的药理研究提供参考。【方法】猪中性粒细胞的提取采用密度梯度离心法,中性粒细胞与猪内皮细胞的黏附采用虎红比色法,中性粒细胞黏附分LFA-1和Mac-1表达量的检测采用流式细胞技术,中性粒细胞p38MAPK、ERK等磷酸化活性检测采用western blot法。【结果】咯利普兰可显著抑制fMLP刺激的中性粒细胞和内皮细胞的黏附(P0.05),极显著抑制fMLP刺激的中性粒细胞LFA-1和Mac-1的表达(P0.01),阻断fMLP刺激的中性粒细胞ERK磷酸化活性(P0.01),而对p38MAPK磷酸化活性无显著影响。【结论】咯利普兰可抑制中性粒细胞和内皮细胞黏附,其机制与阻断中性粒细胞ERK磷酸化进而抑制LFA-1和Mac-1表达有关。 相似文献
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JIANG Dai-xun ZHANG Mei-hua ZHANG Qian CHEN Yi-shan MA Wen-jing WU Wei-peng MU Xiang 《农业科学学报》2015,14(4):758-764
Our previous studies showed that the anti-inflammatory effects of Paeonia lactiflora roots extract may be mediated, at least in part, through its gallic acid content, and this effect may be regulated in part by an inhibition on cAMP-phosphodiesterase (PDE). To explore the anti-inflammatory effect and mechanism, the influence of gallic acid on neutrophils PDE4 activity and expression, TNF-α and IL-6 content and rat arthritis model were further studied. PDE4 activity and gene express were calculated respectively by substrate cAMP change examined with HPLC and real-time RT-PCR. The concentration of IL-6 and TNF-α in supernatant were assayed by ELISA method. Model of rat arthritis was caused by complete Freund’s adjuvant. Results showed that gallic acid had a dose-dependent restraint on PDE4 activity of neutrophils in vitro, promoted significantly PDE4A expression (P<0.01), and had no influence on the expressions of PDE4B and 4D. However, PDE4C expression was not detected. Gallic acid could promote IL-6 release (P<0.05), and inhibit TNF-α release of neutrophils (P<0.05). The experiment in vivo showed that gallic acid had obvious restraint on local inflammation of animal model (P<0.05). Therefore, the anti-inflammatory effect of gallic acid may be mediated in part through an inhibition on PDE4 activity and further an increase of IL-6 and a decrease of TNF-α of neutrophils, and this effect seemed to have no relationship with PDE4 expression. 相似文献
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【目的】以猪中性粒细胞为靶细胞,研究白芍制剂对其相关功能（呼吸爆发和弹性蛋白酶释放）及磷酸二酯酶活性的影响。【方法】中性粒细胞分离纯化后,以细胞色素C还原法检测中性粒细胞呼吸爆发,以弹性蛋白酶底物的减少反映弹性蛋白酶的释放量,以HPLC检测底物cAMP的变化反映磷酸二酯酶的活性等。【结果】白芍制剂呈剂量依赖性抑制中性粒细胞的呼吸爆发（P＜0.001）,3个不同浓度的抑制率分别为33.15%、45.96%和62.22%;对弹性蛋白酶的释放在低浓度时表现抑制作用（P＜0.05）,抑制率为23.22%,在高浓度时表现促进作用;对中性粒细胞磷酸二酯酶活性具有抑制作用,低、高浓度抑制率分别为13.24%和25.87%（P＜0.01）;HPLC指纹图谱分析表明白芍制剂主要存在5种成分。【结论】白芍制剂对猪中性粒细胞呼吸爆发具有明显的抑制作用,对弹性蛋白酶释放在低浓度有显著抑制作用,其作用机制可能与白芍制剂对磷酸二酯酶活性的抑制有关。 相似文献
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中草药对磷酸二酯酶4活性影响的初步研究 总被引：1，自引：0，他引：1
以对磷酸二酯酶4(PDE4)活性的影响为指标,筛选PDE4选择性中草药调节剂,为中兽医药理学研究和临床调节环核苷酸水平提供依据。以cAMP为底物,加入由猪嗜中性粒细胞中提取的PDE4与中草药样品, 用HPLC法检测反应后的cAMP含量,计算中草药对酶活性的影响,正数为抑制作用,负数为促进作用。54味中草药里,对PDE4活性具有抑制作用的有38味,具有促进作用的有16味。部分所选中草药对PDE4活性具有较强的抑制作用,部分具有较强的促进作用,提示从中草药里筛选特异性PDE4活性调节剂是可行的。 相似文献
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猪中性粒细胞磷酸二酯酶基因表达及活性研究 总被引：4，自引：0，他引：4
【目的】通过对猪中性粒细胞磷酸二酯酶（PDE）基因表达、活性及特异性抑制剂实验检测，研究其存在的主要PDE亚型及在体外的活性，为探讨PDE在中性粒细胞的分布、活性变化及对cAMP、cGMP调节与中性粒细胞功能关系提供依据。【方法】采用反转录聚合酶链反应（RT-PCR）检测PDE基因在猪中性粒细胞的表达，以高效液相色谱（HPLC）检测环核苷酸在PDE反应前后的含量变化，计算PDE活性。【结果】在检测的18个PDE亚型中，PDE1B、2A、3A、3B、4A、4B、4C、4D、5A、7A、7B、8A、8B、9A、11A 共15个PDE mRNA在猪中性粒细胞表达，特异性抑制剂实验表明PDE4、PDE5分别为水解cAMP、cGMP的主要PDE亚型；cAMP/cGMP-PDE在10～40 μl范围内，与其活性存在良好的线性关系（r＝0.9929/0.9992）。【结论】猪中性粒细胞至少存在15个PDE亚型，其中PDE4、PDE5为主要存在的2个亚型，PDE样品量在一定范围内与其活性存在良好的线性关系，可作为筛选PDE型中性粒细胞功能调节剂的方法。 相似文献
6.
木犀草素体内抗炎作用机制研究 总被引：6，自引：0，他引：6
目的探讨木犀草素（Lut）的体内抗炎疗效及作用机制。方法采用角叉菜胶致大鼠足爪肿胀模型,观察Lut对足爪肿胀度的影响;酶免疫测定法（EIA）测定炎足足跖部的渗出液前列腺素E2（PGE2）的含量;免疫组织化学法（IHC）及免疫印迹（Western blot）法检测角叉菜胶致炎大鼠足爪组织环氧合酶-2（COX-2）的表达情况。结果Lut可抑制角叉菜胶致炎的大鼠足爪肿胀。80、120 mg/kg Lut可显著降低足爪炎症组织前列腺素E2（PGE2）生成,并显著抑制炎足爪中COX-2的蛋白表达。结论Lut具有较强的抗炎作用,其机制可能与抑制COX-2的表达及PGE2的释放有关。 相似文献
7.
Endothelial adhesiveness for blood neutrophils is inhibited by transforming growth factor-beta 总被引：16，自引：0，他引：16
Adhesion of blood cells to endothelial cells is an essential component of all inflammatory responses. The capacity of the endothelium to support adhesion of neutrophils is increased by cytokines such as tumor necrosis factor-alpha, interleukin-1, and endotoxin. Another cytokine, transforming growth factor-beta (TGF-beta), was a strong inhibitor of basalneutrophil adhesion and also decreased the adhesive response of endothelial cells to tumor necrosis factor-alpha (TNF-alpha). The ability of cells to respond to TGF-beta was related to the duration of culture of endothelial cells after explantation from umbilical veins. TGF-beta is likely to serve an anti-inflammatory role at sites of blood vessel injury undergoing active endothelial regeneration. 相似文献
8.
Down-regulation of LFA-1 adhesion receptors by C-myc oncogene in human B lymphoblastoid cells 总被引：16，自引：0，他引：16
G Inghirami F Grignani L Sternas L Lombardi D M Knowles R Dalla-Favera 《Science (New York, N.Y.)》1990,250(4981):682-686
9.
The mechanisms that control localization of marginal zone (MZ) B cells are poorly understood. Here we show that MZ B cells express elevated levels of the integrins LFA-1 (alphaLbeta2) and alpha4beta1 and that they bind to the ligands ICAM-1 and VCAM-1. These ligands are expressed within the MZ in a lymphotoxin-dependent manner. Combined inhibition of LFA-1 and alpha4beta1 causes a rapid and selective release of B cells from the MZ. Furthermore, lipopolysaccharide-triggered MZ B cell relocalization involves down-regulation of integrin-mediated adhesion. These studies identify key requirements for MZ B cell localization and establish a role for integrins in peripheral lymphoid tissue compartmentalization. 相似文献
10.
Endothelial interleukin-8: a novel inhibitor of leukocyte-endothelial interactions 总被引：45，自引：0，他引：45
M A Gimbrone M S Obin A F Brock E A Luis P E Hass C A Hébert Y K Yip D W Leung D G Lowe W J Kohr 《Science (New York, N.Y.)》1989,246(4937):1601-1603
Certain inflammatory stimuli render cultured human vascular endothelial cells hyperadhesive for neutrophils. This state is transient and reversible, in part because activated endothelial cells secrete a leukocyte adhesion inhibitor (LAI). LAI was identified as endothelial interleukin-8 (IL-8), the predominant species of which is an extended amino-terminal IL-8 variant. At nanomolar concentrations, purified endothelial IL-8 and recombinant human IL-8 inhibit neutrophil adhesion to cytokine-activated endothelial monolayers and protect these monolayers from neutrophil-mediated damage. These findings suggest that endothelial-derived IL-8 may function to attenuate inflammatory events at the interface between vessel wall and blood. 相似文献
11.
Hematogenous metastasis requires the arrest and extravasation of blood-borne tumor cells, possibly involving direct adhesive interactions with vascular endothelium. Cytokine activation of cultured human endothelium increases adhesion of melanoma and carcinoma cell lines. An inducible 110-kD endothelial cell surface glycoprotein, designated INCAM-110, appears to mediate adhesion of melanoma cells. In addition, an inducible endothelial receptor for neutrophils, ELAM-1, supports the adhesion of a human colon carcinoma cell line. Thus, activation of vascular endothelium in vivo that results in increased expression of INCAM-110 and ELAM-1 may promote tumor cell adhesion and affect the incidence and distribution of metastases. 相似文献
12.
目的 观察补阳还五汤精简方对氧化应激损伤后血管内皮细胞的保护作用,并从核转录因子E2相关因子/抗氧化反应元件（NF-E2-related factor 2/ antioxidant response element,Nrf2/ARE）途径探讨其作用机制。方法 采用H2O2作用大鼠血管内皮细胞4 h建立体外血管内皮细胞氧化应激模型,根据不同处理分成正常组,模型组,补阳还五汤含药血清组（补阳组）,补阳还五汤精简方含药血清组（5%精简组、10%精简组、20%精简组）6组。采用倒置显微镜观察细胞形态;流式细胞术检测血管内皮细胞调亡;测定细胞SOD活力、MDA含量;采用Western blot法检测细胞Nrf2、血红素加氧酶-1（HO-1）蛋白的表达。结果 与模型组比较,含药血清组均能不同程度改善细胞形态,升高细胞存活率,其中10%精简组较5%精简组、20%精简组细胞损伤程度低;与模型组比较,补阳组和10%精简组可有效抑制细胞凋亡（P<0.05）;与模型组比较,补阳组及10%精简组可显著提升SOD活力（P<0.01）;补阳组、10%精简组及20%精简组可降低MDA含量（P<0.05）;补阳组及10%精简组可明显上调Nrf2、HO-1蛋白表达（P<0.05）。结论 10%补阳还五汤精简方可以显著减轻氧化应激造成血管内皮细胞的损伤,抑制细胞调亡,这一作用可能与上调Nrf2/ARE抗氧化信号通路途径表达有关。 相似文献
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目的 观察滋阴活血解毒方对糖基化终末产物（advanced glycation end-producs,AGEs）诱导血管内皮细胞（vascular endothelial cell,VEC）损伤的影响及其黏附分子、凝血相关因子表达的变化,进一步探讨该方对AGEs诱导VEC损伤的保护作用。方法 以人脐静脉内皮细胞（human umbilical vein endothelial cells,HUVEC）作为实验对象,以终浓度（100 mg/L）的AGEs诱导HUVEC损伤。各模型组及给药组细胞分别继续培养12、24、48 h。在显微镜下观察各组细胞形态变化,并以Western-blot法检测各组黏附分子VCAM-1、ICAM-1的表达;以RT-PCR方法检测TF、TM mRNA表达。结果 相对于空白组细胞,模型组细胞出现异常增殖,细胞数量明显增多,多数细胞变形皱缩,胞膜轮廓模糊,细胞内出现粗糙样颗粒变化,VCAM-1、ICAM-1、TF表达明显上调,TM表达下调,且在作用24 h后差异有显著性意义（P<0.01）;相同时间点,给药组较模型组圆缩形细胞减少,能下调VCAM-1、ICAM-1、TF表达,上调TM表达,且随着作用时间的延长更明显（P<0.01）。结论 滋阴活血解毒方能抑制AGEs对VEC的损伤,降低黏附分子的表达,下调表达组织因子mRNA转录,上调血栓调节素mRNA转录。 相似文献
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Neutrophil Mac-1 and MEL-14 adhesion proteins inversely regulated by chemotactic factors 总被引：106，自引：0，他引：106
The neutrophil Mac-1 and gp100MEL-14 adhesion proteins are involved in neutrophil extravasation during inflammation. Both the expression and activity of Mac-1 are greatly increased after neutrophil activation. In contrast, neutrophils shed gp100MEL-14 from the cell surface within 4 minutes after activation with chemotactic factors or phorbol esters, releasing a 96-kilodalton fragment of the antigen into the supernatant. Immunohistology showed that gp100MEL-14 was downregulated on neutrophils that had extravasated into inflamed tissue. The gp100MEL-14 adhesion protein may participate in the binding of unactivated neutrophils to the endothelium; rapid shedding of gp100MEL-14 may prevent extravasation into and damage of normal tissues by activated neutrophils. 相似文献
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Gadek TR Burdick DJ McDowell RS Stanley MS Marsters JC Paris KJ Oare DA Reynolds ME Ladner C Zioncheck KA Lee WP Gribling P Dennis MS Skelton NJ Tumas DB Clark KR Keating SM Beresini MH Tilley JW Presta LG Bodary SC 《Science (New York, N.Y.)》2002,295(5557):1086-1089
The protein-protein interaction between leukocyte functional antigen-1 (LFA-1) and intercellular adhesion molecule-1 (ICAM-1) is critical to lymphocyte and immune system function. Here, we report on the transfer of the contiguous, nonlinear epitope of ICAM-1, responsible for its association with LFA-1, to a small-molecule framework. These LFA-1 antagonists bound LFA-1, blocked binding of ICAM-1, and inhibited a mixed lymphocyte reaction (MLR) with potency significantly greater than that of cyclosporine A. Furthermore, in comparison to an antibody to LFA-1, they exhibited significant anti-inflammatory effects in vivo. These results demonstrate the utility of small-molecule mimics of nonlinear protein epitopes and the protein epitopes themselves as leads in the identification of novel pharmaceutical agents. 相似文献
18.
采用组织贴块法培养分离大鼠肺微血管内皮细胞(PMVEC),以高效液相色谱(HPLC)检测环核苷酸(cAMP)在酶反应前后磷酸二酯酶(PDE)的变化计算PDE活性,并分析药物对其影响,为研究PMVEC特异性PDE抑制剂和清热药作用机理积累资料。结果显示:分离培养经CD31鉴定的PMVEC,其酶量在5~20μL范围内与PDE活性存在良好的线性关系(r=0.9929);17味入肺经清热药均对肺组织cAMP-PDE酶活性有不同程度的抑制作用,其中黄芩、黄药子、青蒿抑制率较高,对肺组织酶分别为:75.37%,72%,61.26%,对PMVEC分别为:66.1%,63.54%,59.39%,结果提示以cAMP-PDE活性为指标,有望筛选出其特异性PDE抑制剂,并揭示入肺经清热药的作用机制。 相似文献
19.
嗜水气单胞菌J-1株粘附素及其受体分析 总被引：3，自引：0，他引：3
以EPC细胞和HEp-2细胞为细胞模型，用嗜水气单胞菌（Aeromonas hydrophila,Ah)J－1株进行粘附试验，同时以Ah4型菌毛的抗血清作粘附抑制试验，用以分析AhJ-1株的粘附素及其受体。EPC细胞粘附和粘附抑制试验证实，Ah J-1株粘附素受体具有甘露糖、胆固醇成分，有少量半乳糖成分，无葡萄糖成分。HEp-2细胞粘附和粘附抑制试验证实，与其它非菌毛粘附素如S层及外膜蛋白相比，Ah4型菌毛的粘附作用较为显。抗4型菌毛抗体和抑制细菌的粘附力达80％以上。抗S层、外膜蛋白抗体也能使细菌的粘附力下降，表明Ah的粘附作用由菌毛粘附素与非菌毛粘附素共同参与。 相似文献
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猪嗜中性粒细胞cAMP磷酸二酯酶的提取与活性检测 总被引：7，自引：2，他引：7
目的:提取动物体的cAMP磷酸二酯酶(PDE),并检测其活性,为兽医临床研究PDE活性的生理病理变化和中西药物对PDE活性调节作用建立实验方法。方法:猪血经过葡聚糖沉降,淋巴细胞分离液分离,特殊分离液洗涤和红细胞溶胀后,获得嗜中性白细胞。嗜中性白细胞破碎后释放PDE,通过反相高效液相色谱(RP HPLC)法测定反应体系中cAMP的含量,根据底物(cAMP)的减少量,确定嗜中性白细胞中PDE活性。结果:经显微镜计数嗜中性粒细胞纯度达95%;酶量在10～40μl间对cAMP的分解率为9 90%～31 39%,与PDE活性之间存在直线相关关系(r=0 99)。结论:猪嗜中性粒细胞中含有高纯度、高活性的cAMP PDE;高效液相色谱法可以准确测定PDE反应前后cAMP含量的变化;两种方法结合可以作为兽医临床研究机体PDE活性变化和中西药物对PDE活性调节作用的新方法。 相似文献