同型半胱氨酸对Kkay小鼠糖尿病肾病作用机制的探讨

目的 探讨基质金属蛋白酶-9(MMP-9)在同型半胱氨酸(Hcy)加重糖尿病肾病(DN)过程中的可能作用。方法 22～24周龄Kkay糖尿病鼠16只随机分两组:糖尿病组(KA)和高蛋氨酸组(KB),每组8只;C57BL/6小鼠9只为对照组(C57),以相应饲料喂养4个月后取材。测定血糖和血Hcy水平,以PAS染色观察各组肾组织肾小球病理改变,比较肾小球硬化指数(GI)。对肾脏MMP-9表达进行免疫组化染色和半定量图像分析,并以逆转录PCR检测。肾脏MMP-9 mRNA的表达水平。结果 与C57对照组相比,Kkay两组均有不同程度糖尿病肾病病变,其中KB组病变更重,其GI值(283.33)高于KA组(240.00),P<0.05。免疫组化显示KB组肾小球MMP-9阳性着色面积(15.90％)高于KA组(11.14％),P<0.05,MMP-9 mRNA表达水平KB组高于KA组。结论 高Hcy血症具有加重Kkay小鼠糖尿病肾病程度的作用,此作用可能与上调MMP-9的表达水平有关。     

高同型半胱氨酸血症对糖尿病肾病小鼠细胞间黏附分子-1表达的影响

目的　探讨高同型半胱氨酸 (Hcy)血症对糖尿病肾病 (DN)时细胞间黏附分子 1(ICAM 1)表达的影响。　方法　 2 2～ 2 4周龄Kkay糖尿病鼠 16只随机分两组 :糖尿病 (KA)组和高蛋氨酸 (KB)组 ,每组 8只 ;另以 9只C5 7BL/ 6小鼠为对照 (C5 7) ,以相应饲料喂养 4个月后取材。测定血糖和血Hcy水平 ,以PAS染色观察各组DN病变。对肾脏ICAM 1蛋白表达进行免疫组化染色和半定量图像分析 ;并以RT PCR检测肾脏ICAM 1mRNA的表达水平。　结果　与C5 7对照组相比 ,Kkay两组均有不同程度DN病变 ,其中KB高蛋氨酸组病变最重 ,其肾小球硬化指数 (GI)高于KA组 (P <0 0 5 )。免疫组化显示Kkay小鼠肾脏ICAM 1的表达高低与病理变化一致 ,即KB组ICAM 1阳性着色面积 (19 6 5 % )高于KA组 (15 2 2 % ) (P <0 0 1) ;ICAM 1mRNA表达水平也强于KA组。　结论　Hcy具有加重Kkay小鼠DN程度的作用 ,此作用可能与上调ICAM 1的表达水平有关     

溶血磷脂酸上调THP-1细胞基质金属蛋白酶-9的表达及活性

目的 探讨基质金属蛋白酶9(MMP-9)在溶血磷脂酶(LPA)致动脉粥样硬化中的作用及机制.方法 以不同浓度LPA(0～10 μmol/L)刺激人单核细胞株THP-1细胞4 h,RT-PCR法测定MMP-9 mRNA表达,酶谱法检测MMP-9活性,Western印迹法检测核蛋白NF-κB p65表达变化.结果 随着LPA剂量的增加,MMP-9表达及活性,核蛋白NF-κB p65表达逐渐增强,在LPA 1 μmol/L时达到最高点,然后逐渐减弱,LPA以剂量依赖的方式激活NF-κB,在转录水平促进THP-1细胞MMP-9 mRNA表达,增强MMP-9活性.结论 LPA可能通过激活NF-κB,在转录水平促进THP-1细胞MMP-9 mRNA表达,并增强其活性,促进粥样硬化发生和发展.     

阿托伐他汀对慢性心力衰竭小鼠心肌组织赖氨酰氧化酶表达的影响

目的研究阿托伐他汀对慢性心力衰竭(CHF)小鼠心肌组织赖氨酰氧化酶(LOX)表达的影响及机制。方法选取C57BL/6小鼠复制CHF小鼠模型,再随机分为CHF组10只、阿托伐他汀组11只[阿托伐他汀3 mg/(kg.d)灌胃]和β氨基丙组10只[β氨基丙100mg/(kg.d)灌胃]。另设对照组9只。在4周末将小鼠处死,提取心肌组织RNA及蛋白质,RT-PCR法测定心肌组织LOX、基质金属蛋白酶9(MMP-9)及NF-κB的mRNA表达水平,Western blot测定心肌组织LOX、磷酸化p38及p38蛋白表达水平。结果 CHF组小鼠心肌组织LOX、MMP-9、NF-κB mRNA表达明显高于对照组(P<0.01);阿托伐他汀组心肌组织LOX、MMP-9、NF-κB mRNA表达较CHF组明显下调(P<0.01)。CHF组心肌组织LOX及磷酸化p38蛋白表达明显高于对照组(P<0.01);与CHF组比较,阿托伐他汀组及β氨基丙组心肌组织LOX及磷酸化p38蛋白表达明显下降(P<0.01)。结论阿托伐他汀可逆转CHF小鼠心肌组织LOX的表达,LOX可通过调节CHF小鼠心肌组织MMP-9表达,从而抑制心脏重构,这可能是延缓CHF进展的重要机制。     

氯吡格雷对兔动脉粥样硬化基质金属蛋白酶-9及血管壁核因子-κB表达的影响

目的:观察氯吡格雷对兔动脉粥样硬化(AS)血清基质金属蛋白酶-9(MMP-9)含量、血管壁核因子-κB/p65(NF-κB/p65)含量 mRNA表达的影响。方法:将27只新西兰雄性白兔随机分为正常对照组(A组)、高胆固醇组(B组)和氯吡格雷组(C组)。酶法检测血脂;原位杂交法检测血管壁NF-κB/p65 mRNA表达;固相酶联免疫吸附试验(ELISA)检测MMP-9及血管壁NF-ΚB/p65含量;组织形态学分析AS斑块/内膜面积比值及斑块最厚处内膜/中膜厚度比值。结果:B组和C组血清MMP-9、血管壁NF-κB/p65含量及 mRNA表达均较A组显著升高(P<0.05);C组较B组AS病变明显减轻(P<0.05),MMP-9、血管壁NF-κB/p65含量及 mRNA及p65表达均明显降低(均P<0.05)。结论:氯吡格雷可能具有一定抗AS作用,且抗AS作用机制可能与抑制NF-κB/p65及MMP-9表达有关。     

抑制核转录因子-κB对单核细胞基质金属蛋白酶9表达的影响

目的观察NF-κB抑制剂咖啡酸苯乙酯(CAPE)对溶血磷脂酸(LPA)诱导人单核细胞(THP-1)基质金属蛋白酶9(MMP-9)表达和活性及NF-κB p65表达的影响。方法选用THP-1培养后,分对照组(不加LPA),加0.1、0.5、1、5和10μmol/L LPA依次为1组、2组、3组、4组和5组,刺激THP-1细胞4 h;另选CAPE 20 mg/L预处理1 h,再LPA 1μmol/L处理4 h后为CAPE组,ELISA法测定MMP-9含量,酶谱法检测MMP-9活性,蛋白印迹法检测核蛋白NF-κB p65表达变化。结果与对照组和1组、2组、4组、5组比较,3组MMP-9分泌和活性以及NF-κB p65均显著增加,差异有统计学意义(P0.01);与3组比较,CAPE组明显抑制上述指标(P0.01)。结论 LPA可能通过激活NF-κB,促进MMP-9表达,并增强其活性,而CAPE抑制MMP-9表达。     

MMP-9、TIMP-1和NF-κB在甲状腺乳头状癌中的表达及意义

采用免疫组织化学和原位杂交方法检测157例甲状腺乳头状癌和30例甲状腺乳头状瘤组织中基质金属蛋白酶9(MMP-9)、金属蛋白酶组织抑制因子1(TIMP-1)及NF-κB的表达.结果显示甲状腺乳头状癌中MMP-9及NF-κB的蛋白及mRNA表达阳性率均明显高于乳头状瘤(均P<0.01).MMP-9及NF-κB蛋白和mRNA在甲状腺乳头状癌随着病理分级增高而显著增加(P<0.01);并且颈部淋巴结有转移者均高于无转移者(P<0.01).而TIMP-1蛋白及mRNA阳性表达率与MMP-9阳性表达率相反.     

银杏叶提取物对肾间质成纤维细胞中糖基化终产物诱导的血管生成素及其受体表达的影响

目的:观察糖基化终末产物(AGEs)对肾间质成纤维细胞中血管新生关键调节因子血管生成素(Ang)1、2及其受体酪氨酸激酶受体2(Tie-2)表达的影响,探讨其可能的机制以及抗氧化剂银杏叶提取物(EGb)的干预作用。方法:选择正常大鼠肾间质成纤维细胞系(NRK-49F)为研究对象,以低糖DMEM培养液培养细胞作对照,分别用含AGEs(400mg/L)和高糖(25mmol/L)的DMEM培养液体外培养24h,用抗氧化剂EGb(100mg/L)预处理后再分别加入AGEs和高糖继续培养。采用实时定量PCR检测Ang-1、Ang-2、Tie-2,核因子κB(NF-κB)及其抑制物(I-κB)mRNA表达水平,Westernblot检测蛋白表达水平。二乙酰二氯荧光素(DCFH)染色后荧光倒置显微镜及流式细胞仪检测细胞内活性氧(ROS)水平。结果:与对照组相比,AGEs和高糖组细胞内ROS水平明显升高;且Ang-1及NF-κBmRNA和蛋白表达显著增高,I-κBmRNA和蛋白表达显著下降,Ang-2和Tie-2表达则无明显变化。EGb预处理后可降低细胞内ROS水平及Ang-1和NF-κB表达水平,提高I-κB表达水平,而对Ang-2和Tie-2表达无影响。结论:AGEs可通过增强细胞内氧化应激,抑制I-κB表达而激活NF-κB,上调Ang-1表达,参与糖尿病肾病(DN)血管新生的调控。EGb可通过减少氧化应激,上调I-κB表达,抑制NF-κB途径而下调Ang-1表达,在防治DN方面有良好的应用前景。     

白藜芦醇通过核因子-κB信号通路抑制脑缺血基质金属蛋白酶功能上调

目的 揭示白藜芦醇抑制脑缺血基质金属蛋白酶(MMP)-9功能上调的分子机制及其与核因子(NF)-κB信号通路联系.方法 建立大鼠四动脉前脑缺血模型,采用免疫印迹技术观察缺血后再灌海马脑区MMP-9蛋白水平和NF-κB核易位的变化;给予自由基清除剂白藜芦醇或NF-κB抑制剂吡咯二硫氨基甲酸酯(DTC),识别NF-κB信号通路是否参与了白藜芦醇对脑缺血MMP-9蛋白表达的调控.结果 脑缺血/再灌诱导海马脑区MMP-9蛋白水平和NF-κB核易位增加(P＜0.05).PDTC能一定程度的抑制缺血后MMP-9基因表达(P＜0.05).白藜芦醇能显著抑制脑缺血NF-κB核易位和MMP-9表达上调(P＜0.05).结论 脑缺血再灌,诱导MMP-9依赖NF-κB通路的蛋白水平增加,白藜芦醇能通过抑制NF-κB通路下调MMP-9的功能,继而阻断MMP-9激活介导的胞外基质降解及海马脑区损伤.     

核因子-κB在糖尿病大鼠肾脏的表达水平及贝那普利的调节作用

目的 探讨NF-κB在糖尿病大鼠肾脏中的表达水平及贝那普利的调节作用.方法 将34只Wistar大鼠随机分为正常对照(n)组、糖尿病肾病(DN)组、贝那普利治疗(DNB)组.腹腔注射STZ诱导糖尿病模型,处理12 w末检测血糖、血胆固醇、血肌酐、尿素氮、尿蛋白,应用免疫组织化学方法检测肾脏NF-κB的表达水平.结果 DNB组大鼠血胆固醇、肌酐及尿白蛋白排泄较DN组明显减少(P<0.01或P<0.05).免疫组化显示:DNB组大鼠肾脏NF-κB表达明显低于DN组(P<0.01).结论 贝那普利对糖尿病大鼠肾脏有保护作用,可能通过抑制糖尿病大鼠肾脏NF-κB的表达,减少细胞外基质沉积.     

Immunomodulation of atherosclerosis: myth and reality

Atherosclerosis is an inflammatory disease which displays features of immune activation both locally and systemically. In the present review, we discuss the evidence for immune activation in human disease and experimental models, and survey candidate antigens associated with atherosclerosis. Studies of atherosclerosis in genetic models of immunodeficiency are analysed, as well as immunomodulating therapies and immunization protocols. Based on recent research, it is concluded that immunomodulation represents an interesting approach to the development of new prevention and treatment methods for atherosclerosis.     

Infections as a major preventable cause of human cancer

Infections may be responsible for over 15% of all malignancies worldwide. Important mechanisms by which infectious agents may induce carcinogenesis include the production of chronic inflammation, the transformation of cells by insertion of oncogenes and inhibition of tumour suppressors, and the induction of immunosuppression. Common characteristics shared by infectious agents linked to malignancies are that they are persistent in the host, often highly prevalent in the host population and induce cancer after a long latency. The associations between a selection of infectious agents and malignancies are covered in detail.     

Knowledge of risk of developing diabetes mellitus among siblings of Type 2 diabetic patients.

AIMS: We set out to investigate the extent to which siblings of diabetic subjects perceived themselves likely to develop Type 2 diabetes mellitus (DM) when offered screening tests. METHODS: Nondiabetic siblings, aged 35-74 years, of Type 2 diabetic patients who were more than 35 years old at diagnosis had fasting plasma glucose measured in a study to determine heritability of diabetes. Questionnaires assessing perceived likelihood of developing, seriousness and knowledge about diabetes were completed. Logistic regression assessed factors predicting perceptions of diabetes risk. RESULTS: Factors predicting diabetes on screening were male sex, increasing age and body mass index (BMI) > or = 30. Eighty-nine per cent of 540 eligible siblings completed questionnaires. Thirty-eight per cent saw themselves at increased risk of diabetes and 34% thought diabetes a serious problem. Predictors of perceiving an increased likelihood of developing diabetes were female sex, age 35-54 years vs. 55-74 years and having a parent with diabetes. BMI did not affect perceptions of likelihood. CONCLUSION: A perception of reduced vulnerability to diabetes may occur due to unawareness of risk or minimization of risk. Feelings of invulnerability may affect emotional response to a subsequent result. It is not known whether providing more information about the risk of developing diabetes prior to screening would affect outcomes     

Heterogeneity of autoantibodies against cardiolipin and oxidatively modified LDLs revealed by human monoclonal antibodies

Human monoclonal antibodies against cardiolipin, native and oxidatively modified LDL and against apoB100 were obtained by Epstein-Barr virus transformation of peripheral blood mononuclear cells followed by cloning. The antibodies were used to analyse the cross-reactivity between monoclonals with different specificities and to study the repertoire of antibodies present in sera from patients. Monoclonal antibodies selected for binding to cardiolipin were the least cross-reactive, whereas antibodies against different modifications of LDL frequently also reacted with other modifications. Inhibition studies showed that serum antibodies against cardiolipin and against oxidatively modified LDL were to a different extent inhibited by the different monoclonal antibodies and thus markedly heterogeneous.     

醋柳黄酮对大鼠心肌缺血-再灌注损伤及MMP-9表达的影响

目的观察醋柳黄酮(TFH)对大鼠心肌缺血-再灌注后损伤及组织MMP-9表达的影响,探讨对心肌缺血-再灌注损伤后保护机制。方法将50只大鼠随机分组:模型组、氯沙坦组、醋柳黄酮大、小剂量组及假手术组。结扎左冠状动脉前降支30min后松开制作心肌缺血-再灌注模型。对心肌组织进行HE染色观察心肌坏死的面积及病理变化,免疫组织化学检测再灌注心肌组织MMP-9表达。结果 HE切片观察TFH大、小剂量组预处理的大鼠心肌坏死较模型组明显减轻,免疫组化结果显示TFH大、小剂量组较模型组MMP-9表达减少,有统计学意义。结论TFH对再灌注损伤心肌有保护作用,其作用机制与抑制心肌中MMP-9表达有关。     

Changing concepts of atherogenesis

This review discusses three stages in the life history of an atheroma: initiation, progression and complication. Recruitment of mononuclear leucocytes to the intima characterizes initiation of the atherosclerotic lesion. Specific adhesion molecules expressed on the surface of vascular endothelial cells mediate leucocyte adhesion: the selectins and members of the immunoglobulin superfamily such as vascular cell adhesion molecule-1 (VCAM-1). Once adherent, the leucocytes enter the artery wall directed by chemoattractant chemokines such as macrophage chemoattractant protein-1 (MCP-1). Modified lipoproteins contain oxidized phospholipids which can elicit expression of adhesion molecule and cytokines implicated in early atherogenesis. Progression of atheroma involves accumulation of smooth muscle cells which elaborate extracellular matrix macromolecules. These processes appear to result from an eventual net positive balance of growth stimulatory versus growth inhibitory stimuli, including proteins (cytokines and growth factors) and small molecules (e.g. prostanoids and nitric oxide). The clinically important complications of atheroma usually involve thrombosis. Arterial stenoses by themselves seldom cause acute unstable angina or acute myocardial infarction. Indeed, sizeable atheroma may remain silent for decades or produce only stable symptoms such as angina pectoris precipitated by increased demand. Recent research has furnished new insight into the molecular mechanisms that cause transition from the chronic to the acute phase of atherosclerosis. Thrombus formation usually occurs because of a physical disruption of atherosclerotic plaque. The majority of coronary thromboses result from a rupture of the plaque's protective fibrous cap, which permits contact between blood and the highly thrombogenic material located in the lesion's lipid core, e.g. tissue factor. Interstitial collagen accounts for most of the tensile strength of the plaque's fibrous cap. The amount of collagen in the lesion's fibrous cap depends upon its rate of biosynthesis stimulated by factors released from platelets (e.g. transforming growth factor beta or platelet-derived growth factor), but inhibited by gamma interferon, a product of activated T cells found in plaques. Degradation by specialized enzymes (matrix metalloproteinases) also influences the level of collagen in the plaque's fibrous cap. Such studies illustrate how the application of cellular and molecular approaches has fostered a deeper understanding of the pathogenesis of atherosclerosis. This increased knowledge of the basic mechanisms enables us to understand how current therapies for atherosclerosis may act. Moreover, the insights derived from recent scientific advances should aid the discovery of new therapeutic targets that would stimulate development of novel treatments. Such new treatments could further reduce the considerable burden of morbidity and mortality due to this modern scourge, and reduce reliance on costly technologies that address the symptoms rather than the cause of atherosclerosis.     

Plasma lipoprotein particle concentrations in postmenopausal women with unstable coronary artery disease. Analysis of diagnostic accuracy using receiver operating characteristics

BACKGROUND: The contribution of plasma lipids to cardiovascular risk is usually evaluated by measuring plasma concentrations of total cholesterol, triglycerides and HDL cholesterol, and calculating LDL cholesterol concentration. We investigated plasma concentrations of apolipoproteins and lipoprotein particles in women with unstable coronary artery disease (CAD) to evaluate whether these, better than the routine lipid status, could differentiate women with and without coronary atherosclerosis. METHODS: Blood samples for lipid analyses were collected from 119 angiographically examined postmenopausal 49-79-year-old women with unstable CAD, and from 101 age-matched controls. Mean plasma concentrations were compared and the discriminatory ability of the different variables were tested using receiver operating characteristics (ROC). RESULTS: At coronary angiography 19% had normal vessels and 81% had coronary atherosclerosis. A disturbed triglyceride metabolism was the most pronounced lipid abnormality in women with unstable CAD and coronary atherosclerosis. ROC showed that none of the evaluated variables had a particularly high discriminatory power regarding unstable CAD or coronary atherosclerosis. The ratio cholesterol/HDL cholesterol was best with an ROC area of 0.79. Furthermore, the newer lipid variables, i.e. lipoprotein particles and apolipoproteins, were no better than the traditional variables. CONCLUSION: Lipoprotein changes reflecting a disturbed triglyceride metabolism are most pronounced in women with unstable CAD and coronary atherosclerosis. Lipoprotein particles and apolipoproteins alone were no better than lipids and lipoproteins in separating women with from those without coronary atherosclerosis. Our study does not support the measurement of apolipoproteins and lipoprotein particles on the basis of diagnostic accuracy alone.     

Metabolic syndrome and psychosocial deprivation. Data collected from a Paris suburb

AIM: The association between the metabolic syndrome (MetS) and socioeconomic deprivation has already been recognized. The aim of this study was to examine the relationship between MetS and psychosocial deprivation, and to determine whether or not this relationship is independent of gender, age and obesity. SUBJECTS AND METHODS: The sample included 17074 subjects, aged 16-91 years, who attended the Health Examination Centre of the National Health Insurance Service at Bobigny (a northern suburb of Paris). Exclusion criteria were known diabetes and current lipid-lowering treatment. MetS was defined according to NCEP-ATP III criteria. Psychosocial deprivation was analyzed using the Evaluation of Deprivation and Inequalities by Health Examination Centres (EPICES) score, which includes 11 validated questions and ranges from zero to 100. Psychosocial deprivation was defined as a score greater than or equal to 40. RESULTS: The sample included slightly more women (52.5%) than men, and 52.5% were considered to be deprived. These subjects were slightly older (41 vs 40.2 years, P<0.0001). Around half of the study population benefited from social help. MetS prevalence was higher in the deprived group (11.5% vs 9.4%; P<0.0001), and this was confirmed for every age group. Similarly, the prevalence of all MetS components, except for blood glucose, was significantly higher. The deprivation rate increased with the number of MetS criteria in the non-obese. In a multiple logistic regression, female gender (OR=1.50), age (OR>14 for those over 50 compared with those aged 16-19 years) and deprivation (OR=1.22) were independent predictors of MetS. Taking obese and non-obese populations separately, deprivation remained an independent predictor of MetS only in the non-obese (OR=1.30). CONCLUSION: Psychosocial deprivation is an independent determinant of MetS in non-obese people, and elderly psychosocially deprived women, even if not obese, are at a particularly high risk of MetS. Educational efforts need to be developed to prevent MetS and its consequences in this population.     

Sox9基因转染对骨髓间充质干细胞成软骨分化的影响

目的 探讨Sox9基因转染对骨髓间充质干细胞(MSCs)成软骨分化的影响.方法 采用密度梯度离心和贴壁培养法分离兔骨髓MSCs,体外培养扩增.阳离子脂质体介导重组真核表达Sox9质粒转染骨髓MSCs,通过反转录-聚合酶链反应(RT-PCR)和蛋白印迹实验(Westem blot)的方法检测基因产物的表达,荧光显微镜和流式细胞术测定细胞转染效率;四甲基噻唑蓝(MTT)法测定基因转染对细胞增殖能力的影响,流式细胞术对转基因细胞进行细胞周期分析;通过Westem blot,RT-PCR和免疫组织化学染色的方法检测Sox9基因转染对MSCs成软骨分化的影响.结果 脂质体介导Sox9基因可以成功地转染兔骨髓MSCs;Sox9基因转染对细胞增殖能力无明显影响;基因转染后的细胞表达软骨分化特异性分子Ⅱ型胶原,Sox9,aggrecan等明显增加.结论 Sox9基因转染骨髓MSCs可以获得稳定表达,基因表达产物可以促进骨髓MSCs向软骨方向的分化.     

EgM9免疫犬产生抗体变化规律的观察

目的用重组表达蛋白EgM9免疫实验犬,观察免疫犬的抗体变化及EgM9的免疫效果。方法用100μgEgM9及5mg的GST并辅以佐剂QuilA分别免疫实验犬,定期收集血清,以间接ELISA法检测血清中IgG及其亚类、IgM、IgA与IgE;感染45d后剖检实验犬,统计犬体内虫体数量。结果免疫组和对照组血清IgG与IgA差异显著(P<0.05);而IgG1与IgG2免疫组和对照组差异极显著(P<0.01);IgM与IgE免疫组和对照组无显著差异(P>0.05);相对于对照组,免疫组的保护率达86%。结论用重组蛋白EgM9免疫犬后能产生很高的抗体水平,可以抑制细粒棘球绦虫的发育,EgM9或许有望作为一种有效的候选疫苗成分用于包虫病的防治。