三七总皂苷对急性心梗后左室重构大鼠心功能的改善作用

目的 研究三七总皂苷(PNS)对急性心肌梗塞(AMI)后左室重构(LVRM)大鼠心功能的作用,并与比索洛尔的疗效作比较.方法除假手术组外采用结扎大鼠左冠状动脉前降支的方法建立AMI模型,术后24h后随机分为正常对照组和实验组,连续4周分别灌胃给予生理盐水2 mg· kg-1、比索洛尔25 mg·kg-1和PNS40、80、120 mg·kg-1,观察PNS和比索洛尔对病鼠室间隔舒张末期厚度(IVSd)、左室舒张末期内径(宽度)(LVIDd)、室间隔收缩末期厚度(IVSs)、左室收缩末期内径(宽度)(LVIDs)、左室后壁舒张末期厚度(LVPWd)、左室后壁收缩末期厚度(LVPWs)、左室射血分数(EF)、左室收缩百分率(FS)、二尖瓣口舒张早期血流速度(MV)、心率(HR)等反映心功能变化指标的影响.结果PNS高、中剂量组与比索洛尔组的MV、EF均明显上升(P＜0.01),中剂量PNS组及比索洛尔组的FS明显上升、LVIDd和LVIDs则减小(P＜0.01～0.05).结论PNS及比索洛尔均具有改善AMI后LVRM病鼠心功能的作用,可用于治疗心梗后的左室重构.     

MicroRNAs participate in the cardioprotective activity of dexrazoxane against doxorubicin-induced cardiotoxicity

Background The co-administration of dexrazoxane(DEX)with each dose of doxorubicin(Dox)is an efficient strategy to relieve Dox-induced cardiotoxicity,however,the mechanisms underlying the cardioprotective effect of DEX have not been well elucidated.MicroRNAs(miRNAs)are endogenous,small non-coding RNAs that negatively regulate gene expression in diverse biological and pathological processes.The aim of the present study was to investigate whether the certain cardiac miRNAs were involved in DOX-induced cardiotoxicity.Methods Male SD rats were randomized into five groups,including the 4-week(cumulative dose16 mg / kg)and the 8-week(cumulative dose32 mg / kg)Dox-treated groups,and the corresponding 4-week and 8-week Dox plus DEX-treated groups and the normal control group.Heart functions of the animals were detected by echocardiography.Quantitative real-time PCR was used to determine the expression of cardiac remodeling,apoptosis-related genes and mature micoRNAs of interest.Results The echocardiography detection showed that cardiac remodeling and impaired heart function were observed after 4-week and 8-week Dox treatment,and the cardiac remodeling and decreased ejection fraction(EF%)and fractional shortening(FS%)were efficiently rescued in the corresponding 4-week and 8-week Dox plus DEX-treated groups.The myocardial expression of Anp and CTGF mRNA was significantly upregulated by Dox treatment,but the upregulation of Anp and CTGF mRNA was blocked in the Dox plus DEX-treated groups.IGF-1 mRNA was significantly up-regulated in rat myocardium in Dox plus DEX-treated groups,with no significant changes of Bcl-2 and BAX mRNA expression.Mature miRNAs determination demonstrated that the myocardial miR-1 and -30e were significantly downregulated and miR-21 and -208b were significantly up-regulated in Dox treatment groups,but the above miRNA dysregulation could be efficiently reversed after DEX treatment.Conclusions DEX could tune the microRNAs dysregulation in Dox-treated rat myocardium,miRNAs participated in the cardioprotective activity of DEX against Dox-induced cardiotoxicity.     

一种方便酶切鉴定的shRNA表达载体改建方法

目的 建立一种用单限制性内切酶酶切来快速筛选重组小发夹RNA(shRNA)表达载体的方法.方法 制备包含单一限制性内切酶Cta Ⅰ识别序列的双链DNA插入片段(Cla Ⅰ位点两侧碱基序列不互补).与BamH Ⅰ和Hind Ⅲ线性化的shRNA表达载体pSilencer-4.1(不含Cla Ⅰ识别序列)构建载体pSilencer-4.1-Cla Ⅰ.用BamH Ⅰ和Hind Ⅲ酶切pSilencer-4.1-Cla Ⅰ,将酶切产物与表达绿色荧光蛋白(GFP)shRNA的DNA模板(不含Cla Ⅰ识别序列)做连接反应.构建GFP shRNA表达质粒.提取阳性克隆质粒DNA,行Cla Ⅰ单酶切鉴定,对未被Cla Ⅰ线性化的质粒行DNA测序鉴定.结果 DNA测序表明正确构建了shRNA表达载体pSilencer-4.1-Cla Ⅰ,以pSilencer-4.1-Cla Ⅰ为载体构建的GFPshRNA候选重组子中,不能被Cla Ⅰ线性化的均为GFP shRNA表达质粒.结论 构建了可用于制备shRNA表达质粒的通用载体pSilencer-4.1-Cla Ⅰ,所引入的单一的Cla Ⅰ识别位点可以用来快速地筛选重组shRNA表达质粒.     

三七总皂苷改善心肌梗死后心室重构大鼠心功能作用

目的研究三七总皂苷（PNS）对急性心肌梗死（AMI）后左心室重构（LVRM）大鼠心功能作用。方法除假手术组外采用结扎大鼠左冠状动脉前降支的方法建立AMI模型,术后24h后随机分为对照组和实验组,连续4周分别灌胃给予生理盐水、福辛普利和PNS低、中、高剂量,观察PNS对病鼠室间隔舒张末期厚度（IVSd）、左心室舒张末期内径（宽度）（LVIDd）、室间隔收缩末期厚度（IVSs）、左心室收缩末期内径（宽度）（LVIDs）、左心室后壁舒张末期厚度（LVPWd）、左心室后壁收缩末期厚度（LVPWs）、左心室射血分数（EF）、左心室收缩百分率（Fs）、二尖瓣口舒张早期血流速度（MV）、心率（HR）等反映心功能变化指标的影响。结果PNS中、高剂量组的EF、FS及MV指标均显著提高（P〈0．01～0．05）。结论PNS通过提高左心室收缩和舒张功能,降低外周阻力,对病鼠AMI后LVRM心功能有保护和改善作用。     

二维斑点追踪超声技术监测2型糖尿病大鼠心肌收缩功能损害

目的 采用二维斑点追踪技术监测2型糖尿病大鼠左室心功能变化并与M型超声技术分析比较,评价该技术在糖尿病心肌病变研究中的应用.方法 (1)建模SD大鼠给予STZ 30 mg/kg尾静脉推注后喂高脂饲料,期间监测处理前后大鼠FPG及PG 2h以确定模型建立.(2)超声监测6周时采集大鼠左心室乳头肌平面短轴M型及B型图像,测射血分数值及左心室收缩期应变和应变率峰值;第10、13周时进行大鼠多巴酚丁胺应激负荷实验,收集诱导前及后左心室乳头肌平面短轴M型超声图像,计算EF值.结果 与正常对照组比较,6周后模型大鼠左室心肌部分节段收缩期径向和圆周应变及应变率平均峰值下降(P＜0.05),但大鼠静息态EF值与正常比较无显著差异;第10周时模型组大鼠静息态EF值与正常组比较仍无显著差异,多巴酚丁胺负荷刺激后第3～5 min时EF值出现下降(P＜0.05);第13周时模型组大鼠静息态EF值出现显著下降,负荷刺激后EF值-时间曲线明显下移(P＜0.05).结论 二维斑点追踪技术能够早期发现糖尿病动物的心肌收缩功能损害.     

代谢综合征大鼠左心室应变及应变率与心外膜脂肪的相关性

目的 探讨应变及应变率分析对代谢综合征(MS)大鼠心脏收缩功能的评估价值及其与心外膜脂肪的关系.方法 6周龄雄性SD大鼠16只,随机分为MS模型组8只、对照组8只.给予模型组大鼠小剂量链脲佐菌素、N硝基L精氨酸甲酯盐酸盐联合高脂、高盐、高糖饲养6周.实验开始及结束时测定大鼠的体质量、空腹血糖、胰岛素、血脂指标、口服糖耐...     

Screen for Coronary Artery Disease Specific Genetic Expression by Representational Differential Analysis

Objective To screen coronaryartery disease (CAD) specific expressions and clone their genes. Method Blood samples were collected from CAD and non - CAD patients at the end of coronary angiography. mRNA from samples was isolated and converted into cDNA. After ligated with specific linkers, the cDNA was amplified with complementary primers. PCR products from CAD samples were named as tester; the ones from non - CAD samples were named as driver. With different ratio of tester to driver (1 : 100,1: 1, 000, and 1: 10, 000), they were mixed, denatured, and renatured. Single strand cD-NA was eliminated by Mung bean nuclease. Double strand cDNA presented only in tester was amplified, ligated in vector pUC19 and pUC53, and transformed into E. coll DH5a. Strains with inserted cDNA fragments were picked up based on blue and white selection. Insertions were screened by endonuclease digestion and DNA sequencing. Results were compared with DNA sequences of GeneBank. Results: After the selection with representational     

抗DNA酶B在急性肾小球肾炎诊断的临床应用

抗ＤＮＡ酶Ｂ在急性肾小球肾炎诊断的临床应用董太明黄震东符永恒吴红穗陈剑光陈志红罗健Ａ组溶血性链球菌（ＧＡＳ）感染导致的急性肾小球肾炎（ＡＧＮ）的病原学诊断，国内通常采用抗溶血素Ｏ（ＡＳＯ），到目前为止，尚未见到采用抗脱氧核糖核酸酶Ｂ（抗ＤＮＡ酶Ｂ）微...     

Upregulation of miR-29b contributes to the anti-fibrotic effect of macrophage migration inhibitory factor in diabetic myocardial fibrosis

Background Macrophage migration inhibitory factor(MIF) possesses proinflammatory function when secreted from the cells, and it also exhibits antioxidant properties based on its intrinsic oxidoreductase activity.However, the role of MIF in cardiac fibrosis is not well known. In the present study, the effect of MIF on fibrosis-associated gene expression and the underlying mechanism were examined. Methods The collagen content in mouse myocardium was detected by Masson staining. Expressions of MIF and fibrosis-associated Col1a1, Col3a1 and α-SMA in mouse myocardium or mouse cardiac fibroblasts were detected by quantitative real-time PCR and Western blot assay, respectively. Mature miR-29b expressions in mouse myocardium and cardiac fibroblasts were determined by real-time PCR. Smad3 activation in MIF-treated cardiac fibroblasts was also detected by Western blot assay. Results Compared with the db / m control mice, the collagen content was significantly increased in the myocardium of diabetic db / db mice. MIF was up-regulated, but miR-29b was down-regulated in the diabetic myocardium. Quantitative real-time PCR and Western blot assay showed that MIF could inhibit fibrosis-associated Col1a1, Col3a1 and α-SMA expressions in mouse cardiac fibroblasts.Smad3 activation was inhibited, but miR-29b was up-regulated in MIF-treated cardiac fibroblasts. Enforced expression of miR-29b significantly suppressed Col1a1, Col3a1, and α-SMA mRNA and 1protein expressions in cardiac fibroblasts. Conclusions MIF possesses the anti-fibrosis activity through inhibiting Smad3activation and through up-regulating miR-29b expression, and miR-29b can inhibit fibrosis-associated Col1a1,Col3a1 and α-SMA expressions in cardiac fibroblasts.     

环状RNA _005647通过结合miR-99b-5p抑制心肌细胞中肥厚相关基因的表达

目的研究环状RNA circRNA_005647抑制心肌肥厚相关基因表达的作用机制。方法建立血管紧张素Ⅱ(AngⅡ)灌注诱导的心肌肥厚小鼠模型。原代分离获得C57BL/6乳小鼠心肌细胞(NMVC),AngⅡ处理NMVC建立心肌细胞肥大模型。利用NMVC,分别感染circRNA_005647重组腺病毒(rAd-circRNA_005647)和转染miR-99b-5p模拟物来研究对NMVC肥大的影响。通过双荧光素酶报告基因实验和RNA Pull-down实验验证circRNA_005647与miR-99b-5p的结合作用。实时荧光定量PCR和Western blot检测NMVC中心肌肥厚相关基因的mRNA和蛋白表达水平。结果在AngⅡ诱导的小鼠心肌肥厚模型和心肌细胞肥大模型中,circRNA_005647及其宿主基因肌球蛋白IXA(Myo9a)表达升高。过表达circRNA_005647可抑制AngⅡ诱导的NMVC中肥厚相关基因心房钠尿肽(Anp)和肌球蛋白重链7(Myh7)基因表达升高。circRNA_005647与miR-99b-5p间存在结合作用。过表达circRNA_005647可抑制miR-99b-5p促心肌细胞肥大的作用。结论circRNA_005647通过结合miR-99b-5p发挥抑制心肌细胞肥大的作用。