内脏脂肪素与冠心病

【作者】 刘圣文；

【导师】 乔树宾； 杨跃进； 陈珏；

【作者基本信息】 中国协和医科大学 ， 内科学， 2009， 博士

【摘要】 第一部分内脏脂肪素对脐静脉内皮细胞合成单核细胞趋化蛋白-1和白介素-6影响的研究目的和背景:内脏脂肪素(Visfatin)是一种新的脂肪因子参与调节炎症因子合成和分泌。单核细胞趋化蛋白-1(MCP-1)和白介素-6(IL-6)参与动脉粥样硬化的重要炎症因子之一,本研究探讨内脏脂肪素是否能调节内皮细胞MCP-1和IL-6生成以及信号转导机制。方法:培养3-5代脐静脉内皮细胞(HUVEC),给予不同剂量和不同干预时间的内脏脂肪素刺激HUVEC。内脏脂肪素刺激基础上给予不同蛋白激酶抑制剂:渥曼青霉素(磷酸肌醇3激酶(PI3K)抑制剂)、SB203580(p38丝裂原活化蛋白激酶(MAPK)抑制剂)、PD98059(细胞外信号调节激酶(ERK)抑制剂)、JNK inhibitorⅡ(c-Jun氨基末端激酶(JNK)抑制剂)和HNMPA-(AM)3(胰岛素受体酪氨酸激酶抑制剂),ELISA测定培养液MCP-1和IL-6浓度,实时定量聚合酶链反应(RT-PCR)测定细胞MCP-1和IL-6 mRNA表达。结果:内脏脂肪素刺激HUVEC合成MCP-1和IL-6,呈剂量和时间依赖性,内脏脂肪素浓度为500ng/mL或作用时间48小时后MCP-1和IL-6表达达到高峰;渥曼青霉素、SB203580、PD98059等蛋白激酶抑制剂能阻断内脏脂肪素诱导的MCP-1、IL-6合成,并抑制MCP-1、IL-6 mRNA表达。胰岛素受体抑制剂HNMPA-(AM)3预处理HUVEC,阻断内脏脂肪素诱导的MCP和IL-6蛋白和基因表达。结论:本研究表明内脏脂肪素能诱导HUVEC合成MCP-1和IL-6,其可能的信号转导通路包括p38 MAPK,P13K、ERK 1/2以及胰岛素受体旁路。第二部分内脏脂肪素与炎症、动脉粥样硬化和急性冠脉综合征目的和背景内脏脂肪素(Visfatin)为最近新发现的脂肪因子,能结合胰岛素受体模拟胰岛素发挥作用,可能与肥胖和胰岛素抵抗有关。最近文献表明内脏脂肪素与炎症、内皮功能失调、动脉粥样斑块不稳定性相关。然而内脏脂肪素在动脉粥样硬化的病理生理机制中具体作用还未明确,因此该研究目的为评价血浆内脏脂肪素与炎症、动脉粥样硬化以及急性冠脉综合征(ACS)之间的联系。方法253例临床怀疑冠心病的患者均行冠状动脉造影,分为三组:稳定性心绞痛(SAP)(102例)、ACS(100例)和无冠心病对照组(51例)。测定循环血中内脏脂肪素、单核细胞趋化蛋白-1(MCP-1)、白介素-6(IL-6)、高敏C反应蛋白(hs-CRP)等细胞因子,探讨内脏脂肪素和传统危险因素、炎症、动脉粥样硬化以及急性冠脉综合征之间的联系。结果SAP和ACS患者血浆内脏脂肪素水平较无冠心病对照组患者明显升高(分别为12.0(9.7,15.5)12.0 ng/mL,13.4(11.1,15.9)ng/mL,10.2(8.7,12.8)ng/mL,p＜0.05)。亚组分析表明冠心病患者是否合并糖尿病、高脂血症、肥胖症血浆内脏脂肪素水平无显著性差异。多元线性回归分析表明内脏脂肪素与IL-6、MCP-1、空腹血糖(FPG)正相关,β值分别为0.0029、0.337和0.104。多因素logistic回归分析调整传统危险因素和炎症性因素后显示血浆内脏脂肪素水平与SAP和ACS密切相关。血浆内脏脂肪素水平位于第2、3、4四分位数区间的人群SAP危险比数比(OR)分别为1.74(0.96,2.69)、1.54(0.85,2.28)和1.84(0.98,2.87),ACS分别为2.56(1.57,3.34)、4.61(1.94,10.96)和6.52(2.34,18.12)。结论血浆内脏脂肪素水平与冠心病相关,尤其是与ACS相关,独立于其它传统危险因素。更多还原

【Abstract】 Part One Effects of visfatin on production of monocyte mhemotactic protein-1 and interleukin-6 in Human Vein Umbilical Endothelial CellsObjective and Backgroud:Visfatin is a novel adipocytokine affecting insulin resistance by binding to the insulin receptor and considered a new proinflammatory adipocytokine. Monocyte chemotactic protein-1(MCP-1) and interleukin-6(IL-6) are importantly inflammatory cytokines involved in atherosclerosis.Whether visfatin stimulates MCP-1 and IL-6 production in human endothelial cells and what signaling pathways are involved in are not known.Methods:Cultured human umbilical vein endothelial cells(HUVEC) were treated with different doses and durations of visfatin.Furthermore,HUVEC were pretreated with wortmannin,a phosphatidylinositol-3-kinase(PI3K) inhibitors,PD98059,an extracellular regulated kinase kinase(ERK) inhibitor,SB203580,a mitogen-activated protein kinase(p38 MAPK) inhibitors and hydroxy-2-naphthalenylmethylphosphonic acid trisacetoxymethyl ester(HNMPA-(AM)3),a specific inhibitor of insulin receptor (IR) followed by visfatin(100ng/mL) treatment.Enzyme-linked immunosorbent assay (ELISA) was used for measuring MCP-1 and IL-6 production in HUVEC.Real-time quantitative reverse-transcription polymerase chain reaction(Real-time-PCR) was used for determining MCP-1 and IL-6 mRNA expression.Results:In the present study,we demonstrated that visfatin significantly and dose-and time-dependently up-regulated protein production of MCP-1 and IL-6 in HUVEC,which the dose of 500ng/mL or 48 hours duration of visfatin treatment had the maximal effect. We therefore found visfatin-induced MCP-1 and IL-6 production and gene expression in HUVEC were diminished by wortmannin,PD98059 and SB203580.Furthermore, HNMPA-(AM)3 also reduced visfatin-mediated MCP-1 and IL-6 production and gene expression in HUVEC.Conclusions:Our findings suggest that visfatin might induce endothelial MCP-1 and IL-6 production in HUVEC with dose- and time-dependently manner.This dysregulation appears to be mediated in part via p38,PI3K and ERK signaling pathways,as well as insulin receptor pathway. Part Two Association between Plasma Visfatin Levels and Inflammation, Atherosclerosis,and Acute Coronary Syndromes in HumansObjective and Backgroud:Visfatin is a new cytokine that act as an insulin analog on the insulin receptor and may link to obesity and insulin resistance.It was recently shown visfatin play a role in inflammation,dysfunction of endothelium and plaque destabilization.However,the role of visfatin in atherosclerosis remains to be elucidated. We sought to assess whether plasma visfatin level can be independently associated with inflammation,atherosclerosis,and acute coronary syndromes(ACS).Mathods:Two hundred fifty-three patients undergoing coronary angiography were divided into three subgroups:stable angina pectoris(SAP)(n=102),ACS(n=100) and the control patients(n=51).Clinical and biochemical characteristics were collected.The plasma samples were thawed and analyzed for circulating visfatin,monocyte chemoattractant protein 1(MCP-1),interleukin-6(IL-6) by enzyme-linked immunosorbent assay(ELISA).The levels of high-sensitivity C-reactive protein(hs-CRP) were determined by immunoturbidometry,The association of visfatin with risk factors, inflammation and atherosclerosis,as well as ACS were determined.Results:Plasma visfatin levels were significantly higher in SAP(12.0(9.7,15.5)pg/mL, p＜0.05) and ACS(13.4(11.1,15.9) pg/mL,p＜0.01)compared with control patients (10.2(8.7,12.8) pg/mL).Subgroup analysis in all patients with coronary artery disease confirmed that plasma visfatin level were not significantly difference in with or without diabetes,with or without hyperlidimia,with or without obesity.Multiple regression analysis demonstrated that plasma visfatin levels positively correlated with MCP-1,IL-6 and FPG(βvalue for MCP-1,IL-6,FPG were 0.0029,0.337,0.104,respectively). Logsitic regression analysis demonstrated that plasma visfatin levels were associated with SAP(odds ratio[OR][95%confidence interval],for in the second,third and fourth quartiles were 1.74[0.96 to 2.69],1.54[0.85 to 2.28]and 1.84[0.98 to 2.87], respectively),ACS(ORs for in the second,third and fourth quartiles were 2.56[1.57 to 3.34],4.61[1.94 to 10.96]and 6.52[2.34 to 18.12],respectively)following adjustment for established risk factors and other inflammatory factors. Conclusions:Plasma visfatin levels are significantly associated with CAD,particularly ACS,independent of well-known CAD risk factors.更多还原