益肝康等活血化瘀中药抑制IL-1β刺激的HSC增殖及TIMP-1的表达

目的:探讨活血化瘀中药益肝康、丹参小复方、丹参对IL-1β刺激的活化的大鼠肝星状细胞(HSCs)增殖及基质金属蛋白酶抑制因子 mRNA(TIMP mRNA)表达的影响．方法:体外培养活化的大鼠HSC,随机分为8 组:对照组(A组)、IL-1β 10 μg/L(B组)、IL- 1β 10μg/L 益肝康2 g/L干预组(C组)、IL- 1β 10 μg/L 丹参小复方2g/L干预组(D组)、 IL-1β 10μg/L 丹参2g/L干预组(E组)、丹参 2 g／L(F组)、丹参小复方2 g/L(G组)、益肝康 2 g／L(H组)．加药后24 h．应用活细胞计数试剂盒-CCK-8检测各组HSC增殖,采用半定量 RT-PCR方法检测各组HSC TIMP-1 mRNA的表达．结果:A组HSC增殖和TIMP-1 mRNA表达强于F、G、H组(1．291±0．09 vs 1．055±0．105, 1±0．07,0．883±0．06,P<0．01:0．591±0．064 vs 0．493±0．088．0．458±0．076．0．356±0．046． P<0．05或P<0．01);H组HSC增殖和TIMP-1 mRNA表达低于F组和G组(P<0．05);B组HSC 增殖和TIMP-1 mRNA表达均明显强于A组 (1．575±0．017 vs 1.291±0,09,P<0．01;1．369± 0．097 vs 0．591±0．064,P<0．01)和C、D、E组 (1．575±0．017 vs 0．906±0．09,1．015±0．081, 1．097±0．038,P<0．01;1．369±0．097 vs 0．694 ±0．078,0．854±0．05,0．898±0．12,P<0．01);C 组HSC增殖和TIMP-1 mRNA表达低于D组和 E组(P<0．05)．结论:益肝康等活血化瘀中药能抑制IL-1β刺激的HSCs增殖及TIMP-1 mRNA表达,发挥其抗肝纤维化功效．益肝康抗肝纤维化作用强于丹参小复方和丹参单药．     

纤维蛋白原对内皮细胞t-PA和PAI-1 mRNA表达的影响

目的 探讨纤维蛋白原（Ｆｇ）对内皮细胞（ＥＣ）组织型纤溶酶原激活物（ｔ－ＰＡ）和纤溶酶原灭活剂（ＰＡＩ－１） ｍＲＮＡ表达的影响。方法 不同浓度Ｆｇ与ＥＣ孵育不同时间后,用单管逆转录聚合酶链反应（ＲＴ－ＰＣＲ）半定量法检测ｔ－ＰＡ和ＰＡＩ－ｍＲＮＡ的表达。结果 用２０,２００,２０００ｍｇ／Ｌ Ｆｇ与ＥＣ孵育１、１２、２４ｈ、ＰＡＩ－１ ｍＲＮＡ的相对表达水平分别为同时相对照组的１．７,３．６,２     

Oxidised-HDL3 induces the expression of PAI-1 in human endothelial cells. Role of p38MAPK activation and mRNA stabilization

Modified lipoproteins have been suggested to modulate endothelial expression of plasminogen activator inhibitor-1 (PAI-1). As oxidized high-density lipoprotein (Ox-HDL) has been found in atheromatous plaques and receptors for modified HDL are present on endothelial cells, we investigated the role of Ox-HDL3 on the expression of PAI-1. Ox-HDL3 but not native HDL3, increased PAI-1 mRNA expression in endothelial cells. Furthermore, PAI-1 antigen expression and activity increased in the supernatant of cells incubated with Ox-HDL3. The intracellular pathways involved in this effect were investigated. Ox-HDL3 activated both extracellular signal-regulated kinases (ERK) 1/2 and p38 mitogen-activated protein kinase (MAPK). Moreover, incubation with specific inhibitors of these kinases showed that p38MAPK was mainly involved in the Ox-HDL3-dependent PAI-1 induction. Transient transfection experiments suggested that none of the response elements in the proximal promoter (-804 to 17) were involved in Ox-HDL3-mediated PAI-1 expression. mRNA stability experiments showed that Ox-HDL3 increased the PAI-1 mRNA half-life. In summary, Ox-HDL3 induced PAI-1 mRNA expression and antigen release through a molecular mechanism involving MAPK activation and mRNA stabilization. Thus, oxidative modification converts HDL to a prothrombotic lipoprotein species.     

罗格列酮对糖基化终产物干预的人肾系膜细胞fractalkine表达的影响

观察罗格列酮和糖基化终产物对人肾系膜细胞fractalkine(FKN)表达的影响.结果 显示糖基化终产物能上调人肾系膜细胞的FKN表达,而罗格列酮能抑制糖基化终产物引起的FKN表达增加.     

Staurosporine对尼古丁诱导人脐静脉内皮细胞表达t-PA与PAI-1的影响

目的 通过观察不同浓度Staurosporine (STS)对尼古丁诱导人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs)表达组织型纤溶酶原激活物(tissue type plasminogen activator,t-PA)与1型纤溶酶原激活物抑制剂(plasminogen activator inhibitor-1,PAI-1)mRNA及蛋白的影响,探讨尼古丁所致内皮细胞纤溶紊乱的机制.方法 将体外培养的3～6代HUVECs随机分为对照组、尼古丁组及不同浓度STS组,STS组分别以20、50、100μmol/L STS预处理细胞30 min,再与100 μmol/L尼古丁孵育24 h.酶联免疫吸附双抗体夹心法检测细胞上清液t-PA与PAI-1蛋白含量,RT-PCR检测PAI-1 mRNA表达.结果 尼古丁组PAI-1 mRNA与蛋白表达较对照组升高(P值均＜0.05);不同浓度STS组PAI-1 mRNA与蛋白表达较尼古丁组降低(P值均＜0.05),且呈浓度依赖性,以100 μmol/L STS组作用为著,但PAI-1 mRNA与蛋白表达仍高于对照组(P值均＜0.05).各组间t-PA蛋白差异无统计学意义(P值均＞0.05).结论 STS通过阻断蛋白激酶C通路的信号传导可部分减弱尼古丁诱导的血管内皮细胞纤溶功能紊乱.     

Aspirin inhibits monocyte chemoattractant protein-1 and interleukin-8 expression in TNF-alpha stimulated human umbilical vein endothelial cells

Atherosclerosis and its complications such as stroke, myocardial infraction and peripheral vascular disease, remain the major causes of morbidity and mortality in the world. Studies have showed that chemokines and adhesion molecules are involved in causing atherosclerosis by promoting directed migration of inflammatory cells. Monocyte chemoattractant protein-1 (MCP-1) is one of the key factors critical for the initiating and developing of atherosclerotic lesions. IL-8, a CXC chemokine, stimulates neutrophil chemotaxis. Aspirin is the most common drug used to prevent the complications of atherosclerosis such as stroke and coronary heart disease. In this study, we found that aspirin inhibited TNF-alpha (10 ng/ml)-induced MCP-1 and IL-8 expression at the RNA and protein levels in human umbilical vein endothelial cells (HUVECs), monocyte adhesion and transmigration, and that its inhibitory effects were not due to decreased HUVEC viability as assessed by MTT test. Aspirin at the dose as low as 10 microg/ml significantly inhibited the release of TNF-stimulated MCP-1 by 29.1% (P = 0.008) and IL-8 by 26.9% (P = 0.0146) as compared to TNF-stimulated release. Antibodies pretreatment were likely to decrease the production of MCP-1 (P < 0.0001) and IL-8 (P < 0.0001). Furthermore, aspirin (10 microg/ml) inhibited U937 cell adhesion by a 13.4% (P = 0.0119) inhibition as compared to TNF-stimulated alone. Finally, at higher concentration, aspirin also inhibited U937 migration to HUVEC by 89.1% (P = 0.0475) as compared to TNF-stimulated alone. These results in our study suggest that aspirin inhibits TNF-alpha stimulated MCP-1 and IL-8 release in HUVECs, for its additional therapeutic effects of aspirin in causing atherosclerosis.     

色素上皮衍生因子抑制糖基化终产物介导人肾小球系膜细胞糖基化终产物受体表达的研究

目的 观察色素上皮衍生因子（PEDF）、晚期糖基化终产物受体（RAGE）的表达及重组PEDF对RAGE表达的抑制作用,探讨PEDF与DN的关系及对DN的保护作用. 方法 采用糖化小牛血清白蛋白（AGE-BSA）体外诱导人肾小球系膜细胞（HRMCs）,Western blot及RT-PCR法分别检测RAGE、PEDF蛋白和mRNA表达. 结果 （1） AGE-BSA（100～400 mg/L）呈浓度梯度减少HRMCsPEDF表达（P＜0.01）,升高RAGE表达（P＜0.01）;（2）重组PEDF蛋白（5～40 nmol/L）呈浓度依赖性抑制AGE-BSA介导RAGE蛋白在HRMCs的表达（P＜0.05）. 结论 AGEs通过降低PEDF表达,增加RAGE表达参与DN的发生,PEDF可能通过抑制AGE-RAGE轴对DN发挥保护作用.     

马来酸罗格列酮抑制糖基化终产物诱导的人肾系膜细胞RANTES高表达

目的探讨马来酸罗格列酮对糖基化终产物（AGEs）诱导的人肾系膜细胞（HRMC）趋化因子RANTES高表达的影响,及其对糖尿病大鼠血清糖基化终产物-肽（AGE-P）及肾脏RANTES表达的影响。方法运用糖基化修饰的牛血清白蛋白（AGE-BSA）与马来酸罗格列酮干预体外培养的HRMC,EusA法检测细胞培养上清中RANTEs蛋白水平,实时定量RT-PCR检测细胞中RANTES mRNA水平,Western blot检测RANTES蛋白表达。制备2型糖尿病大鼠模型,马来酸罗格列酮治疗10周。流动注射分析法测定血清AGEP,免疫组织化学检测肾皮质RANTES表达。结果马来酸罗格列酮干预组HRMC RANTES的mRNA和蛋白表达以及蛋白分泌明显低于AGE-BSA组;马来酸罗格列酮治疗组糖尿病大鼠血清AGE-P明显下降,肾皮质RANTES表达明显低于糖尿病非治疗组。结论马来酸罗格列酮可以抑制AGE-BSA诱导的HRMC RANTES的表达和分泌,还可降低糖尿病大鼠血清AGE-P及肾脏RANTES表达。     

9-顺式维甲酸抑制PMA诱导人单核细胞系THP-1表达MMP-9

目的探讨视黄醛X受体（retinoid X receptors,RXRs）特异性激动剂9-顺式维甲酸（9-cisRA）对佛波酯（PMA）诱导人单核细胞系THP-1基质金属蛋白酶-9（MMP-9）表达及活性的影响。方法体外培养THP-1细胞,PMA诱导分化为巨噬细胞,采用9-cisRA对不同浓度PMA组进行干预,应用Realtime-PCR、Westerblotting测定THP-1细胞MMP-9的基因和蛋白水平表达水平,通过Gelatin Zymography法检测MMP-9的酶活性。结果9-cisRA（100nmol/L）对不同浓度PMA组（10、20和40 nmol/L）干预24 h,9-cisRA可明显抑制THP-1细胞MMP-9转录水平,MMP-9的mRNA抑制率分别28%、60%、88%（P<0.01）。MMP-9蛋白水平及酶活性也呈显著下降。结论RXRs特异性激动剂9-cisRA可显著抑制PMA诱导THP-1的MMP-9转录和蛋白水平表达及其酶活性。     

普罗布考抑制氧化低密度脂蛋白诱导人脐静脉内皮细胞Fractalkine的表达

目的:探讨氧化低密度脂蛋白(ox-LDL)诱导人脐静脉内皮细胞(HUVEC)产生趋化因子Fractalkine及普罗布考的抑制作用.方法:用不同浓度的ox-LDL刺激HUVEC及用不同浓度普罗布考和PDTC预处理细胞后再用ox-LDL刺激,半定量RT-PCR方法检测Fractalkine和NF-κB p65的mRNA的表达.结果:未用ox-LDL刺激的HUVEC不表达Fractalkine,分别用25、50、100 mg/L浓度的ox-LDL刺激后,Fractalkine mRNA的表达呈浓度依赖性增加,与空白对照组比较分别增加384.58%(P＜0.01)、484.09%(P＜0.01)、558.26%(P＜0.01),同时NF-κB p65 mRNA的表达分别增加15.71%(P＞0.05),41.73%(P＜0.01),66.72%(P＜0.01).40 μmol/L PDTC预处理后,再用50 mg/L ox-LDL刺激HUVEC,NF-κB p65 mRNA的表达下降25.61%(P＜0.01),分别用20、40、80 μmol/L的普罗布考干预后,NF-κB p65 mRNA的表达分别下调15.52%(P＜0.05)、24.92%(P＜0.01)、34.93%(P＜0.01);同时,Fractalkine mRNA的表达则分别下调32.22%(P＜0.01)、10.07%(P＞0.05)、20.59%(P＜0.01)、33.60%(P＜0.01).结论:ox-LDL可以通过NF-κB p65诱导HUVEC表达Fractalkine,而普罗布考则可以抑制Fractalkine的表达,这种作用可能与抑制NF-κB p65有关.     

Erythropoietin receptor mRNA expression in human endothelial cells.

A previous report demonstrated that endothelial cells have erythropoietin receptors and respond to this hormone with enhanced proliferation. The present study demonstrates the existence of mRNA for erythropoietin receptor in human umbilical vein endothelial cells. We have reverse transcribed mRNA of endothelial cells and then used different PCR primers to amplify erythropoietin receptor target cDNA between exons 5 and 6 as well as 3-5 in addition to an internal standard DNA fragment. Correspondence of size as well as location of restriction endonuclease scission (Ava II) was used in comparing the amplified fragments of human endothelial cell erythropoietin receptor to those of two human erythroleukemia cell lines, OCIM1 and K562. No alpha- or gamma-globin mRNA was detected in endothelial cells but was readily demonstrable in OCIM1 cells. In addition, to determine whether the expression of human erythropoietin receptor on endothelial cells occurs in vivo, sections of umbilical cord and placenta were immunostained with antibodies against the extracellular portion of the receptor; the results showed strong positive staining of the vascular endothelium.     

Fluvastatin inhibits matrix metalloproteinase-1 expression in human vascular endothelial cells

Matrix metalloproteinase-1 (MMP-1), also called interstitial collagenase, may play an important role in the pathogenesis of atherosclerosis and atherosclerotic plaque rupture. We investigated the effects of fluvastatin on MMP-1 expression in human vascular endothelial cells (ECs). The addition of fluvastatin decreased the basal MMP-1 levels in the culture media of ECs in a time-dependent (0 to 48 hours) and dose-dependent (10(-)(8) to 10(-)(5) mol/L) manner. On the other hand, fluvastatin did not affect tissue inhibitor of metalloproteinase-1 levels. Collagenolytic activity in conditioned media of ECs was also dose-dependently reduced by fluvastatin. The effect of fluvastatin on MMP-1 expression was completely reversed in the presence of mevalonate or geranylgeranyl-pyrophosphate, but not in the presence of squalene. Inhibition of Rho by C3 exoenzyme also significantly decreased MMP-1 expression in ECs. Our findings revealed that fluvastatin decreases MMP-1 expression in human vascular ECs through inhibition of Rho.     

Antagonism by PGF2alpha of the vasodilation induced by PGE1, PGE2 and PGA1 in the canine uterus.

Prostaglandins appear to play an important role in a number of reproductive processes. The present study was designed to determine if the vasodilator action of prostaglandins of the A and E series on uterine vascular smooth muscle was mediated via a receptor and if PGF2alpha could compete for this same receptor. The data demonstrate that PGF2alpha, which by itself has no uterine vascular effect, can produce a parallel shift in the dose-response curves for certain vasodilator prostaglandins. This action, which suggests competitive antagonism, may well play a role in regulating blood flow in the nonpregnant uterus.     

PAI-1 produced ex vivo by human adipose tissue is relevant to PAI-1 blood level.

Human adipose tissue has been shown to produce plasminogen activator inhibitor type 1 (PAI-1). However, the importance of adipose tissue in the regulation of the PAI-1 plasma level is not known. The aim of this study was to investigate the relation between the production of PAI-1 by adipose tissue, plasma PAI-1 level, and variables related to the insulin resistance state. The link between the production of PAI-1 inducers such as tumor necrosis factor-alpha and transforming growth factor-beta and the production of PAI-1 by adipose tissue was also evaluated. Blood samples were obtained as soon as possible to the induction of anesthesia from 30 patients undergoing elective abdominoplasty. PAI-1 antigen levels measured in conditioned media after a 19-hour incubation period of adipose tissue explants were significantly correlated with plasma PAI-1 antigen levels (r=0.54, P=0.004) and with systemic lipid parameters such as triglycerides and high density lipoprotein cholesterol (r=0. 46, P=0.014; r=-0.50, P=0.01, respectively) but not with insulinemia and body mass index. PAI-1 production by adipose tissue was correlated with those of TNF-alpha (r=0.5, P=0.01) and TGF-beta (r=0. 53, P=0.007). These results emphasize the role of adipose tissue in determining plasma levels of PAI-1, with a local contribution of TNF-alpha and TGF-beta in PAI-1 production by adipose tissue.     

PAI-1 mRNA expression and plasma level in rheumatoid arthritis: relationship with 4G/5G PAI-1 polymorphism

Rheumatoid arthritis (RA) is a chronic inflammatory disease affecting the synovial membrane, cartilage and bone. PAI-1 is a key regulator of the fibrinolytic system through which plasminogen is converted to plasmin. The plasmin activates the matrix metalloproteinase system, which is closely related with the joint damage and bone destruction in RA. The aim of this study was to investigate the relationship between 4G/5G PAI-1 polymorphism with mRNA expression and PAI-1 plasma protein levels in RA patients. 113 RA patients and 123 healthy subjects (HS) were included in the study. The 4G/5G PAI-1 polymorphism was determined by polymerase chain reaction?Crestriction fragment length polymorphism method; the PAI-1 mRNA expression was determined by real-time PCR; and the soluble PAI-1 (sPAI-1) levels were quantified using an ELISA kit. No significant differences in the genotype and allele frequencies of 4G/5G PAI-1 polymorphism were found between RA patients and HS. However, the 5G/5G genotype was the most frequent in both studied groups: RA (42%) and HS (44%). PAI-1 mRNA expression was slightly increased (0.67 fold) in RA patients with respect to HS (P?=?0.0001). In addition, in RA patients, the 4G/4G genotype carriers showed increased PAI-1 mRNA expression (3.82 fold) versus 4G/5G and 5G/5G genotypes (P?=?0.0001), whereas the sPAI-1 plasma levels did not show significant differences. Our results indicate that the 4G/5G PAI-1 polymorphism is not a marker of susceptibility in the Western Mexico. However, the 4G/4G genotype is associated with high PAI-1 mRNA expression but not with the sPAI-1 levels in RA patients.     

High glucose concentration inhibits the expression of membrane type metalloproteinase by mesangial cells: possible role in mesangium accumulation

Aims/hypothesis. High glucose concentration decreases the degradation of mesangium matrix, an action substantially mediated by a reduction in the activities of the matrix metalloproteinases (MMPs). Metalloproteinase-2 is unique in that it is activated on the cell surface by one of the membrane type metalloproteinases (MT1-MMP), a process involving complex interactions with tissue inhibitor of metalloproteinase-2. The aim of this study was investigate the effects of glucose concentration on mesangial cell gene expression of MT1-MMP and its ability to modulate the activation of metalloproteinase-2. Methods. Gene expression was determined using competitive RT-PCR, protein expression of MMP-2 was measured by western blot and its activation by zymography. Concanavalin A, known to increase MT1-MMP expression was added in some experiments. Results. High glucose concentration decreased MT1-MMP gene expression (11.52 ± 1.63 and 4.84 ± 0.72 amol/μg RNA, 5 vs 25 mmol/l glucose, respectively) and decreased activation of MMP-2 by 30 % despite a twofold increase in gene expression of MMP-2. Concanavalin A increased expression of MT1-MMP and activation of MMP-2. Irrespective of whether MMP-2 was from endogenous or exogenous source there was an excellent correlation between the MT1-MMP expression and degree of MMP-2 activation, whereas the gene expression of TIMP-2 was not significantly altered by high glucose concentration or concanavalin A. Conclusions/interpretation. Our results indicate that in a high glucose milieu, suppression of MT1-MMP expression could explain the low MMP-2 activity in the presence of high MMP-2 expression. This process could contribute to the mesangium matrix accumulation in diabetic nephropathy. [Diabetologia (2000) 43: 642–648] Received: 18 November 1999 and in revised form: 17 January 2000     

Characterization and purification of a secreted plasminogen activator inhibitor (PAI-1) induced by transforming growth factor-beta 1 in normal rat kidney (NRK) cells: decreased PAI-1 expression in transformed NRK cells

Type 1 transforming growth factor-beta (TGF beta 1) was found to be a potent inducer of the secretion of a 49,000 mol wt protein by normal rat kidney (NRK) cells. This protein was related to type 1 plasminogen activator inhibitor (PAI-1) on the basis of molecular mass, activity in the presence of sodium dodecyl sulfate, immunoprecipitation by antibodies to PAI-1, and N-terminal sequence analysis. PAI-1 levels in the conditioned medium of NRK cells were increased 5- to 11-fold when cells were incubated with picomolar concentrations of TGF beta 1 for 24 h, reaching a concentration of approximately 0.3 microgram/ml. The secreted PAI-1 was deposited in the NRK extracellular matrix as well as released into the culture medium. A spontaneously transformed NRK cell line was found to secrete 3-4 times less PAI-1, in the absence or presence of TGF beta 1, compared to the parent cell line, while PAI-1 secretion in Kirsten sarcoma virus-transformed NRK cells was almost completely abrogated. A novel purification procedure was established, which results in the isolation of highly active and detergent-free TGF beta 1-induced PAI-1.