高血压病患者血浆PAI-1、t-PA及t-PA/PAI-1水平的变化

目的通过对原发性高血压患者血浆纤溶酶原活化物抑制剂1(PAI-1)、组织型纤溶酶原活化物(t-PA)含量及t-PA/PAI-1比值的测定,了解高血压患者纤溶功能的情况。方法未用药物干预过的轻至中度原发性高血压患者(高血压组)64例,正常对照组42例,采用酶联免疫吸附双抗体夹心法测定两组血浆PAI-1、t-PA含量并计算t-PA/PAI-1。结果正常组PAI-1含量明显低于高血压组,(13.5±5.0)μg/L vs(53.0±22.6)μg/L(P<0.01);正常组t-PA/PAI-1明显高于高血压组,(0.83±0.52)μg/L vs(0.25±0.13)μg/L(P<0.01)。结论高血压患者的纤溶功能减退。     

Role of p38 mitogen-activated protein kinase in antiphospholipid antibody-mediated thrombosis and endothelial cell activation

BACKGROUND: The purpose of this study was to examine whether SB 203580, a p38 mitogen-activated protein kinase (MAPK) inhibitor, is effective in reversing the pathogenic effects of antiphospholipid antibodies. METHODS: The adhesion of THP-1 monocytes to cultured endothelial cells (EC) treated with immunoglobulin G (IgG) from a patient with antiphospholipid syndrome (IgG-APS) or control IgG (IgG-NHS) in the presence and absence of SB 203580 was examined. The size of an induced thrombus in the femoral vein, the adhesion of leukocytes to EC of cremaster muscle, tissue factor (TF) activity in carotid artery and in peritoneal macrophages, the ex vivo expression of vascular cell adhesion molecule-1 (VCAM-1) in aorta preparations and platelet aggregation were studied in mice injected with IgG-APS or control IgG-NHS and with or without SB 203580. RESULTS: SB 203580 significantly reduced the increased adhesion of THP-1 to EC in vitro, the number of leukocytes adhering to EC, the thrombus size, the TF activity in carotid arteries and in peritoneal mononuclear cells, and the expression of VCAM-1 in aorta of mice, and completely abrogated platelet aggregation induced by IgG-APS. CONCLUSION: These data suggest that targeting the p38 MAPK pathway may be valuable in designing new therapy modalities for treating thrombosis in patients with APS.     

Regulation of local availability of active tissue-type plasminogen activator in vivo in man.

Free, biologically active tissue-type plasminogen activator (tPA) is the main initiator of intravascular fibrinolysis, but little is known about the regulation of active tPA on the organ level. The aim was to investigate if the local availability of active tPA on the organ level depends on the local release rate of tPA or the arterial input of tPA and plasminogen activator inhibitor type 1 (PAI-1). Also, we wanted to evaluate if plasma levels predict capacity for endothelial release of fibrinolytic proteins. Invasive perfused-forearm studies were performed in 96 healthy subjects. Local release rates of fibrinolytic proteins were assessed at baseline and during endothelial stimulation. Stimulation by methacholine and desmopressin induced a 6- and 12-fold increase in total tPA release rates, respectively. With increasing local release rates of tPA a gradually closer correlation emerged between the total tPA secretion and the forearm output of active tPA (from r = 0.102, ns to r = 0.85, P < 0.0001). Forearm availability of active tPA was not related to arterial input of either tPA or PAI-1. Release rates and plasma levels of tPA were not correlated. Baseline release rates of active tPA increased to noon. The major determinant for the local availability of active tPA is the capacity of the endothelium to release tPA rather than the arterial input of PAI-1 or tPA. Despite a molar excess of PAI-1, the majority of tPA released during stimulation does not undergo local inactivation. The capacity to release tPA locally cannot be predicted from its plasma concentration.     

The regulation by fibrinogen and fibrin of tissue plasminogen activator kinetics and inhibition by plasminogen activator inhibitor 1

BACKGROUND: Tissue plasminogen activator (tPA) is unusual in the coagulation and fibrinolysis cascades in that it is produced as an active single-chain enzyme (sctPA) rather than a zymogen. Two chain tPA (tctPA) is produced by plasmin but there are conflicting reports in the literature on the behaviour of sc- and tctPA and little work on inhibition by the specific inhibitor plasminogen activator inhibitor-1 (PAI-1) under physiological conditions. OBJECTIVES: To perform a systematic study on the kinetics of sctPA and tctPA as plasminogen activators and targets for PAI-1. METHODS: Detailed kinetic studies were performed in solution and in the presence of template stimulators, fibrinogen and fibrin, including native fibrin and partially digested fibrin. Numerical simulation techniques were utilized to cope with the challenges of investigating kinetics of activation and inhibition in the presence of fibrin(ogen). RESULTS: Enzyme efficiency (k(cat)/K(m)) was higher for tctPA than sctPA in solution with chromogenic substrate (3-fold) and plasminogen (7-fold) but in the presence of templates, such as fibrinogen and native or cleaved fibrin, the difference disappeared. sctPA was more susceptible to PAI-1 in buffer solution and in the presence of fibrinogen; however, in the presence of fibrin, PAI-1 inhibited more slowly and there was no difference between sc and tctPA. CONCLUSIONS: Fibrinogen and fibrin modulate the activity of tPA differently in regard to their activation of plasminogen and inhibition by PAI-1. Fibrinogen and fibrin stimulate tPA activity against plasminogen but fibrin protects tPA from PAI-1 to promote fibrinolysis.     

慢性心力衰竭患者血浆组织型纤溶酶原激活物和纤溶酶原激活物抑制物-1含量变化及其临床意义

目的　研究慢性心力衰竭 (CHF)患者血浆组织型纤溶酶原激活物 (t PA)和纤溶酶原激活物抑制物 1(PAI 1)含量的变化及其临床意义。方法　用酶联免疫吸附法 (ELISA)检测 6 0例CHF患者 (CHF组 )和 2 0例健康体检者 (正常对照组 )血浆t PA及PAI 1抗原含量。结果　CHF组血浆t PA和PAI 1平均含量都明显高于对照组 (P<0 .0 1)。CHF患者血浆PAI 1含量增高随心功能恶化而愈加明显。结论　CHF患者纤溶功能明显下降 ,可用血浆t PA、PAI 1含量作为判断病情的参考指标之一。     

达格列净通过p38丝裂原活化蛋白激酶抑制高糖诱导的人肾小球足细胞损伤

目的 探讨达格列净通过p38丝裂原活化蛋白激酶（p38 MAPK）信号通路对D-葡萄糖诱导的人肾小球足细胞凋亡、自噬、炎症反应及氧化损伤的影响。方法 体外培养人肾小球足细胞（HGPCs），分为对照组（5 mmol/L D-葡萄糖）、D-葡萄糖组（30 mmol/L D-葡萄糖）、达格列净组（30 mmol/L D-葡萄糖＋50 μmol/L达格列净）、抑制剂组（30 mmol/L D-葡萄糖＋10 μmol/L p38 MAPK通路抑制剂SB 203580）、达格列净＋抑制剂组（30 mmol/L D-葡萄糖＋50 μmol/L达格列净＋10 μmol/L SB 203580）和达格列净＋激活剂组（30 mmol/L D-葡萄糖＋50 μmol/L达格列净＋10 μmol/L p38 MAPK通路激活剂C16-PAF）。对照组与D-葡萄糖组用D-葡萄糖干预24 h；其他组D-葡萄糖干预24 h后相应药物继续干预 24 h。采用细胞计数试剂盒-8（CCK-8）检测细胞活力；采用Hoechst 33258染色法检测细胞凋亡率；采用ELISA检测白细胞介素（IL）-1β、IL-6、肿瘤坏死因子α（TNF-α）、丙二醇（MDA）和超氧化物歧化酶（SOD）的表达水平；采用实时荧光定量PCR（RT-qPCR）检测酵母ATG6同源物（Beclin-1）、微管相关蛋白1轻链3 Ⅱ（LC3 Ⅱ）mRNA表达水平；采用Western印迹法检测Beclin-1、LC3 Ⅱ、p53、p38 MAPK及p-p38 MAPK蛋白表达。结果 与对照组相比，D-葡萄糖组细胞活力降低（P＜0.05），达格列净组细胞活力升高（P＜0.05），细胞凋亡率，IL-1β、IL-6、TNF-α、MDA、Beclin-1、LC3 ⅡmRNA和蛋白、p53和p-p38 MAPK蛋白水平升高（P＜0.05），SOD水平降低（P＜0.05）。与D-葡萄糖组相比，达格列净组和抑制剂组细胞凋亡率、IL-1β、IL-6、TNF-α、MDA、Beclin-1、LC3 ⅡmRNA和蛋白、p53和p-p38 MAPK蛋白水平降低（P＜0.05），SOD水平升高（P＜0.05）。与达格列净组相比，达格列净＋抑制剂组细胞凋亡率、IL-1β、IL-6、TNF-α、MDA、Beclin-1、LC3 Ⅱ mRNA和蛋白、p53和p-p38 MAPK蛋白水平进一步降低（P＜0.05），SOD水平进一步升高（P＜0.05）；达格列净＋激活剂组与达格列净＋抑制剂组变化趋势相反，与达格列净组差异有统计学意义（P＜0.05）。结论 达格列净可抑制高糖诱导的人HGPCs的凋亡、自噬、炎症反应及氧化损伤，其作用机制可能与抑制p38 MAPK通路信号转导相关。     

脑梗死患者血浆组织型纤溶酶原激活物和纤溶酶原激活物抑制物活性的变化与神经功能缺损的相关性

INTRODUCTIONItwasreportedthatlow-fibrinolysisstatecharacterizedwithdecreaseoftissue-typeplasminogenactivator(t-PA)activityandincreaseoftype1plasminogenactivatorinhibitor(PAI-1)activityexistedinthepathologicalprocessofarterioscleroticcerebralinfarction犤1犦.Butre-centanimalexperimentshowedthatmRNAoft-PAandu-PAex-pressedincreasinglyinischemiccerebraltissue犤2犦.Sofurtherobser-vationwasindispensable.Wetestedtheactivityofplasmat-PAandPAI-1of91patientswitharterioscleroticcerebralinfarct…     

参与骨关节炎的P38丝裂原活化蛋白激酶信号转导通路

背景：p38丝裂原活化蛋白激酶信号转导通路属于丝裂原活化蛋白激酶家族成员,在骨关节炎的发生发展中发挥重要作用。目的：对骨关节炎病理进程中 p38丝裂原活化蛋白激酶信号转导通路相关作用机制的研究进展进行综述。方法：由第一作者用计算机检索中国期刊全文数据库和 PubMed 数据库,检索词分别为“p38丝裂原活化蛋白激酶信号通路、骨关节炎、关节软骨、软骨细胞”和“p38MAPK signal transduction pathway, osteoarthritis, Articular cartilage,Chondrocyte”。从 p38丝裂原活化蛋白激酶信号通路简介,p38丝裂原活化蛋白激酶在骨关节炎中的作用,p38丝裂原活化蛋白激酶阻断剂在骨关节炎中的应用3方面进行总结。共检索到可应用文献90篇,按纳入标准对文献进行筛选,共纳入46篇文章。结果与结论：p38丝裂原活化蛋白激酶信号通路与软骨细胞的肥大化和钙化、软骨细胞的凋亡、软骨基质金属蛋白酶的合成、软骨炎性细胞因子的产生等有密切关系,对骨关节炎的发生发展有重要影响。p38丝裂原活化蛋白激酶通过多种复杂的机制参与骨关节炎的形成和发展,对其起到极其重要的作用,因此阻断 p38丝裂原活化蛋白激酶信号通路可能成为骨关节炎治疗的新靶点。     

肝星状细胞增殖与p38丝裂原活化蛋白激酶信号传导通路的关系

背景:肝星状细胞的激活、增殖导致肝纤维化,p38丝裂原活化蛋白激酶信号通路可参与调控细胞增殖。目的:探讨SB203580作用于乙醛刺激的大鼠肝星状细胞后p38丝裂原活化蛋白激酶活性变化和细胞增殖变化。方法:体外培养大鼠肝星状细胞株,在乙醛干预的基础上加入不同浓度的p38特异性抑制剂SB203580进行培养,并设置对照。以Westernblot检测磷酸化p38蛋白表达水平变化,MTT比色法检测细胞增殖。结果与结论:乙醛刺激后大鼠肝星状细胞内磷酸化p38水平增强,细胞增殖明显。使用5,10,20μmol/L SB203580能明显抑制乙醛刺激的肝星状细胞增殖(P<0.05),加大浓度至30μmol/L时,抑制作用更明显(P<0.01),抑制率为43.9%,而磷酸化p38水平也降低(P<0.05)。结果证实,抑制p38丝裂原活化蛋白激酶活性可能影响肝星状细胞的增殖。     

Influence of thrombin-activatable fibrinolysis inhibitor and plasminogen activator inhibitor-1 gene polymorphisms on tissue-type plasminogen activator-induced recanalization in ischemic stroke patients

OBJECTIVE: Endogenous resistance to tissue-type plasminogen activator (t-PA) might decrease the benefit of thrombolysis-induced recanalization. Thrombin-activatable fibrinolysis inhibitor (TAFI) and plasminogen activator inhibitor-1 (PAI-1) are fibrinolysis inhibitors. TAFI removes residues from partially degraded fibrin that in turn eliminates plasminogen binding sites; PAI-1 directly inhibits the activity of t-PA. We aimed to study whether the presence of two common functional polymorphisms of the TAFI and PAI-1 genes influence rates of recanalization of the middle cerebral artery (MCA) among t-PA-treated stroke patients. METHODS AND RESULTS: TAFI and PAI-1 polymorphism determinations were performed by restriction fragment length polymorphism mapping and conventional sequencing in 139 patients with strokes involving the MCA and who received t-PA within 3 h. Recanalization was diagnosed by means of transcranial Doppler. No association was found between PAI-1 4 G/5 G polymorphism and recanalization rate. Dyslipidemia and TAFI Thr325Ile polymorphism were the main variables associated with recanalization resistance by the end of t-PA infusion: odds ratio (OR) 4.1 [95% confidence interval (95% CI) 1.6-10.8, P = 0.003] and OR 5.6 (95% CI 1.2-20, P = 0.031), respectively. The combination of the two polymorphisms doubled the risk of absence of recanalization: OR 11.1 (95% CI 1.4-89.8, P = 0.025). CONCLUSIONS: Polymorphic fibrinolysis inhibitor genes influence t-PA-induced recanalization resistance in ischemic stroke patients, especially when coexisting in the same patient. Efforts to individualize thrombolytic treatments are required.     

Retinoids and activation of PKC induce tissue‐type plasminogen activator expression and storage in human astrocytes

Summary. Background: Emerging data demonstrate important roles for tissue‐type plasminogen activator (t‐PA) in the central nervous system (CNS). In contrast to endothelial cells, little is known about the regulation of t‐PA gene expression and secretion in astrocytes. Objectives: The aims of the present study were to investigate whether t‐PA gene expression is regulated by retinoids and the protein kinase C (PKC) activator phorbol 12‐myristate 13‐acetate (PMA) in human astrocytes, and to study whether t‐PA is stored and subject to regulated release from these cells, as with endothelial cells. Methods: Native human astrocytes were treated with RA and/or PMA. mRNA was quantified by real‐time RT‐PCR and protein secretion determined by ELISA. Intracellular t‐PA immunoreactivity in astrocytes was examined by immunocyto‐ and histochemistry. Results: RA and/or PMA induced a time‐dependent increase in t‐PA mRNA and protein levels in astrocytes, reaching 10‐fold after combined treatment. This was associated with increased amounts of t‐PA storage in intracellular granular structures. Both forskolin and histamine induced regulated release of t‐PA. The presence of t‐PA in reactive astrocytes was confirmed in human brain tissue. Conclusions: These data show that RA and PKC activation induce a strong up‐regulation of t‐PA expression in astrocytes, and increased intracellular storage pools. Moreover, a regulated release of t‐PA can be induced from these cells. This raises the possibility that astrocytes contribute to the regulation of extracellular t‐PA levels in the CNS.     

血栓调节蛋白和组织纤溶酶原激活物-纤溶酶原激活物抑制剂-1复合物在热射病中的诊断价值

目的 探讨热射病时血栓调节蛋白(TM)和组织纤溶酶原激活物-纤溶酶原激活物抑制剂-1复合物(t-PAIC)的临床价值。方法 回顾性分析解放军联勤保障部队第九〇八医院重症医学科2016年6月至2022年9月收治的45例中暑患者，根据中暑严重程度分为热衰竭组(n=23)和热射病组(n=22)。收集患者入科2 h内的常规凝血项目和血栓弹力图(TEG)指标以及血栓标志物TM、凝血酶-抗凝血酶复合物(TAT)、纤溶酶-α₂纤溶酶抑制剂复合物(PIC)、t-PAIC,并进行统计学分析。结果 与热衰竭组患者TM[7.3(5.4,9.3)TU/mL]、TAT[2.6(1.5,7.2)ng/mL]、PIC[0.7(0.4,1.0)μg/mL]、t-PAIC[3.8(2.1,7.0)ng/mL]相比，热射病组患者TM[17.1(9.2,24.7)TU/mL]、TAT[23.4(10.4,44.3)ng/mL]、PIC[2.0(0.9,5.2)μg/mL]和t-PAIC[17.0(8.3,44.1)ng/mL]均升高(P<0.05)。单因素联合多因素Logistic回归分析显示，...     

Plasma plasminogen activator inhibitor 1, insulin resistance and android obesity

Plasma plasminogen activator inhibitor 1 (PAI-1) levels are elevated in insulin-resistant subjects and are associated with increased cardiovascular risk of atherothrombosis. Strong association between PAI-1 and the metabolic components of the insulin resistance syndrome is found in clinical studies, suggesting that insulin resistance may regulate circulating PAI-1. However, the mechanisms underlying increased PAI-1 levels in such conditions are still poorly understood. Several studies have been carried out specifically in patients with central or android obesity, a major characteristic of the insulin resistance syndrome, and have suggested that visceral adipose tissue may be the major component of the relationship between android obesity and PAI-1. Accordingly, adipose tissue PAI-1 production was found to be elevated in obese human subjects, particularly in visceral adipose tissue. The genetic background for having high PAI-1 levels in several populations have been looked for and its role appeared to be weaker than that of the metabolic condition. High plasma PAI-1 levels are then clearly related to android obesity and insulin resistance, but the mechanisms whereby PAI-1 increases in plasma in these diseases remain to be determined.     

Tissue plasminogen activator antigen is strongly associated with myocardial infarction in young women

Women who develop acute myocardial infarction (AMI) at a young age have fewer classical risk factors and less coronary stenosis than older women. In this rare population, it is plausible that a heightened hemostatic system may play an important mechanistic role in thrombus formation and in the development of AMI. We chose to investigate whether or not there is an association between premature AMI and the plasma concentrations of five hemostatic measurements that had been previously established as risk factors for AMI, and of the inflammation marker C-reactive protein (CRP). Women who had survived AMI at the age of 45 years or less (n = 141) were drawn from those admitted to 125 Italian coronary care units over a 3-year period. In them, and in an equal number of controls, plasma levels of immunoreactive tissue plasminogen activator (tPA), plasminogen activation inhibitor 1 (PAI-1), von Willebrand factor (VWF), fibrinogen, D-dimer and CRP were measured. Higher levels of VWF, fibrinogen, CRP and tPA were associated with AMI. After adjustment for both classical and hemostatic risk factors, only tPA maintained an independent association with AMI: the odds ratios (taken as an index of relative risk) for tPA values in the middle and higher tertiles were 2.86 (CI 1.63-5.02) and 8.18 (CI 2.66-25.20), respectively. In conclusion, there is a strong association between non-fatal AMI and increased plasma levels of tPA antigen. This finding is thought to be the expression of a reduced rather than enhanced fibrinolytic activity.     

螺内酯对醛固酮刺激下大鼠肾小球系膜细胞PAI-1表达的影响

目的探讨醛固酮对体外培养大鼠肾小球系膜细胞纤溶酶原激活物抑制物－1（PAl-1）表达的影响及螺内酯的干预作用。方法体外培养大鼠肾小球系膜细胞,设正常对照组、醛固酮（10-7mol·L-1）组、不同浓度螺内酯（10-7,10-8,10-9mol·L-1）干预组,48h后收集细胞及上清液,以RT-PCR检测PM-1、醛固酮受体（MR）和保护其配体特异性的11p羟类固醇脱氢酶2（11β-HSD2）的mRNA表达,采用ELISA检测培养细胞上清中PAI-1蛋白的浓度。结果RT-PCR结果,肾小球系膜细胞表达MR和118．HSD2mRNA,醛固酮可显著上调肾小球系膜细胞PM-1mRNA表达,螺内酯可抑制醛固酮诱导的PA／-1mRNA表达,且呈剂量依赖性;ELISA结果示醛固酮组上清液中PAI-1水平明显增加,螺内酯干预组PAI-1水平明显降低并与浓度有关。结论螺内酯与醛固酮竞争结合MR,抑制醛固酮刺激的大鼠。肾小球系膜细胞中PAI-1mRNA的表达和蛋白合成。     

左西孟旦调控LOX-1/p38 MAPK通路减轻冠状动脉微栓塞后心肌损伤

目的:探讨左西孟旦（levosimendan,Levo）对冠状动脉微栓塞（coronary microembolization, CME）后心肌损伤和LOX-1/p38 MAPK信号通路的影响。方法:采用随机数字表法将24只巴马小型猪随机分为假手术组（Sham组）、CME组、CME+左西孟旦预治疗+对照腺相关病毒转染组（CME+Levo+NC组）及CME+左西孟旦预治疗+ LOX-1过表达腺相关病毒转染组（CME+Levo+LOX-1组）,每组6只。经冠脉介入法于前降支注射栓塞微球构建CME模型;Sham组则注射等量生理盐水代替。CME+Levo+NC组和CME+Levo+LOX-1组于造模前2周分别转染对照病毒和LOX-1过表达病毒,并均于造模前24 h开始持续静滴左西孟旦。心脏超声检测心功能指标;苏木精-伊红（HE）染色和苏木精碱性复红-苦味酸（HBFP）染色分别用于观察心肌组织病理改变和心肌微梗死区域;酶联免疫吸附测定（ELISA）用于检测血清肌钙蛋白I（cTnI）;脱氧核糖核苷酸末端转移酶介导的缺口末端标记法（TUNLE）检测心肌细胞凋亡率;免疫荧光观察心肌组织LOX-1、Bcl-2、Bax、Caspase-3 p12和p-p38 MAPK蛋白表达情况。多组间比较采用单因素方差分析,组间两两比较采用LSD- t检验。以 P<0.05为差异有统计学意义。 结果:⑴与Sham组比较,CME组小型猪左心室射血分数（LVEF） [（69.73±4.79）% vs （47.18±2.33）%, P<0.05]、左心室短轴缩短率（LVFS） [（42.47±2.54）% vs （21.43±1.76）%, P<0.05]、心输出量（CO）[（4.42±0.27）L/min vs （2.57±0.17）L/min, P<0.05]均显著下降,而左心室舒张期末径（LVEDd）[（32.37±1.33）mm vs （41.21±1.86）mm, P<0.05]显著增加,心肌微梗死面积占比[（3.73±0.87）% vs （20.72±2.49）%, P<0.05]显著增加,血清cTnI水平[（51.92±16.62）pg/mL vs （236.80±19.56）pg/mL, P<0.05]显著升高,心肌细胞凋亡率[（1.15±0.47）% vs （14.15±3.24）%, P<0.05]显著升高,心肌组织Bax、Caspase-3 p12、LOX-1和p-p38 MAPK蛋白表达明显上调（均 P<0.05）,Bcl-2蛋白表达明显下调（ P<0.05）。⑵与CME组比较,CME+Levo+NC组小型猪LVEF[（47.18±2.33）% vs （55.48±3.92）%, P<0.05]、LVFS[（21.43±1.76）% vs （32.02±1.75）%, P<0.05]、CO[（2.57±0.17）L/min vs （3.45±0.25）L/min, P<0.05]均显著升高,而LVEDd[（41.21±1.86）mm vs （36.78±1.56）mm, P<0.05]显著下降,心肌微梗死面积占比[（20.72±2.49）% vs（11.63±3.12）%, P<0.05]显著减小,血清cTnI水平[（236.80±19.56）pg/mL vs （157.40±15.13）pg/mL, P<0.05]显著降低,心肌细胞凋亡率[（14.15±3.24）% vs （8.33±1.28）%, P<0.05]显著下降,心肌组织Bax、Caspase-3 p12、LOX-1和p-p38 MAPK蛋白表达明显下调（均 P<0.05）,Bcl-2蛋白表达明显上调（ P<0.05）。⑶与CME+Levo+NC组比较,CME+Levo+LOX-1组小型猪LVEF[（55.48±3.92）% vs（48.52±1.69）%, P<0.05]、LVFS[（32.02±1.75）% vs （23.80±2.51）%, P<0.05]、CO[（3.45±0.25）L/min vs （4.25±0.23）L/min, P<0.05]均显著降低,而LVEDd[（36.78±1.56）mm vs （41.12±1.57）mm, P<0.05]显著增加,心肌微梗死面积占比[（11.63±3.12）% vs （18.93±1.58）%, P<0.05]显著增加,血清cTnI水平[（157.40±15.13）pg/mL vs （244.40±15.97）pg/mL, P<0.05]显著升高,心肌细胞凋亡率[（8.33±1.28）% vs （12.28±1.93）%, P<0.05]显著增加,心肌组织Bax、Caspase-3 p12、LOX-1和p-p38 MAPK蛋白表达明显上调（均 P<0.05）,Bcl-2蛋白表达明显下调（ P<0.05）。 结论:左西孟旦可通过抑制LOX-1/p38 MAPK信号通路介导的心肌细胞凋亡而减轻CME后心肌损伤。     

左西孟旦调控LOX-1/p38 MAPK通路减轻冠状动脉微栓塞后心肌损伤

目的:探讨左西孟旦（levosimendan,Levo）对冠状动脉微栓塞（coronary microembolization, CME）后心肌损伤和LOX-1/p38 MAPK信号通路的影响。方法:采用随机数字表法将24只巴马小型猪随机分为假手术组（Sham组）、CME组、CME+左西孟旦预治疗+对照腺相关病毒转染组（CME+Levo+NC组）及CME+左西孟旦预治疗+ LOX-1过表达腺相关病毒转染组（CME+Levo+LOX-1组）,每组6只。经冠脉介入法于前降支注射栓塞微球构建CME模型;Sham组则注射等量生理盐水代替。CME+Levo+NC组和CME+Levo+LOX-1组于造模前2周分别转染对照病毒和LOX-1过表达病毒,并均于造模前24 h开始持续静滴左西孟旦。心脏超声检测心功能指标;苏木精-伊红（HE）染色和苏木精碱性复红-苦味酸（HBFP）染色分别用于观察心肌组织病理改变和心肌微梗死区域;酶联免疫吸附测定（ELISA）用于检测血清肌钙蛋白I（cTnI）;脱氧核糖核苷酸末端转移酶介导的缺口末端标记法（TUNLE）检测心肌细胞凋亡率;免疫荧光观察心肌组织LOX-1、Bcl-2、Bax、Caspase-3 p12和p-p38 MAPK蛋白表达情况。多组间比较采用单因素方差分析,组间两两比较采用LSD- t检验。以 P<0.05为差异有统计学意义。 结果:⑴与Sham组比较,CME组小型猪左心室射血分数（LVEF） [（69.73±4.79）% vs （47.18±2.33）%, P<0.05]、左心室短轴缩短率（LVFS） [（42.47±2.54）% vs （21.43±1.76）%, P<0.05]、心输出量（CO）[（4.42±0.27）L/min vs （2.57±0.17）L/min, P<0.05]均显著下降,而左心室舒张期末径（LVEDd）[（32.37±1.33）mm vs （41.21±1.86）mm, P<0.05]显著增加,心肌微梗死面积占比[（3.73±0.87）% vs （20.72±2.49）%, P<0.05]显著增加,血清cTnI水平[（51.92±16.62）pg/mL vs （236.80±19.56）pg/mL, P<0.05]显著升高,心肌细胞凋亡率[（1.15±0.47）% vs （14.15±3.24）%, P<0.05]显著升高,心肌组织Bax、Caspase-3 p12、LOX-1和p-p38 MAPK蛋白表达明显上调（均 P<0.05）,Bcl-2蛋白表达明显下调（ P<0.05）。⑵与CME组比较,CME+Levo+NC组小型猪LVEF[（47.18±2.33）% vs （55.48±3.92）%, P<0.05]、LVFS[（21.43±1.76）% vs （32.02±1.75）%, P<0.05]、CO[（2.57±0.17）L/min vs （3.45±0.25）L/min, P<0.05]均显著升高,而LVEDd[（41.21±1.86）mm vs （36.78±1.56）mm, P<0.05]显著下降,心肌微梗死面积占比[（20.72±2.49）% vs（11.63±3.12）%, P<0.05]显著减小,血清cTnI水平[（236.80±19.56）pg/mL vs （157.40±15.13）pg/mL, P<0.05]显著降低,心肌细胞凋亡率[（14.15±3.24）% vs （8.33±1.28）%, P<0.05]显著下降,心肌组织Bax、Caspase-3 p12、LOX-1和p-p38 MAPK蛋白表达明显下调（均 P<0.05）,Bcl-2蛋白表达明显上调（ P<0.05）。⑶与CME+Levo+NC组比较,CME+Levo+LOX-1组小型猪LVEF[（55.48±3.92）% vs（48.52±1.69）%, P<0.05]、LVFS[（32.02±1.75）% vs （23.80±2.51）%, P<0.05]、CO[（3.45±0.25）L/min vs （4.25±0.23）L/min, P<0.05]均显著降低,而LVEDd[（36.78±1.56）mm vs （41.12±1.57）mm, P<0.05]显著增加,心肌微梗死面积占比[（11.63±3.12）% vs （18.93±1.58）%, P<0.05]显著增加,血清cTnI水平[（157.40±15.13）pg/mL vs （244.40±15.97）pg/mL, P<0.05]显著升高,心肌细胞凋亡率[（8.33±1.28）% vs （12.28±1.93）%, P<0.05]显著增加,心肌组织Bax、Caspase-3 p12、LOX-1和p-p38 MAPK蛋白表达明显上调（均 P<0.05）,Bcl-2蛋白表达明显下调（ P<0.05）。 结论:左西孟旦可通过抑制LOX-1/p38 MAPK信号通路介导的心肌细胞凋亡而减轻CME后心肌损伤。