王璐;姜宗来;齐颖新
目的:房室传导阻滞是心脏电激动传导过程中,发生在心房和心室之间的电激动传导异常,可导致心律失常。前期,我们发现一个遗传性房室传导阻滞伴肥厚型心肌病家系,本次工作主要对其致病基因及机制进行研究。方法:采用候选基因测序的方法对已经确诊为房室传导阻滞的心脏病患者进行致病基因分析,对报道与心脏病相关的 TRP4、 SCN5A、 SCN1B、NKFX2.5、CLCA2和LMNA共6个基因测序并确定致病基因;构建致病基因的野生型和突变型质粒;克隆野生型和突变型,激光共聚焦显微镜检测野生和突变型蛋白在细胞定位,利用Western blot检测目的蛋白的表达情况对该突变功能进行分析。结果:遗传学分析显示在家系中患者LMNA基因第10号外显子缺失,并与疾病共分离。 Western blot结果显示突变型lamin蛋白表达水平正常,定位结果显示,野生型蛋白位于细胞核核膜,而突变型蛋白在核膜上和核内均有表达。 LMNA异常可引起房室结细胞死亡与纤维化,导致房室传导速率降低,并发生房室传导阻滞。自噬和凋亡是细胞死亡的重要形式,LC3-II是检测自噬的标志蛋白。应用Western blot检测LC3-II,结果显示LMNA突变不影响该蛋白表达。结论:本次研究中,我们发现了一个新的导致遗传性房室传导阻滞伴肥厚型心肌病的LMNA基因突变,该突变可使其编码的蛋白不能正确定位于细胞核膜,导致细胞核核纤层结构异常。核纤层在细胞分裂中呈现周期性的变化,因此核纤层的异常会对细胞正常周期产生重要影响从而导致细胞的异常死亡。这可能是导致该家族成员发生房室传导阻滞的原因。
作者:曹祝兵;李思思;臧小彪;凃欣 刊期: 2016年第08期
目的:探讨miR-130a在血管紧张素II(angiotensin II, Ang II)诱导心脏间质纤维化中的作用及分子机制。方法:埋植Ang II微渗泵制备小鼠心室重塑模型,超声心动检测小鼠心功能;离体培养乳鼠心脏成纤维细胞,real-time PCR和Western blot检测分子的基因及蛋白表达。结果:在埋植Ang II微渗泵的小鼠心肌组织以及Ang II刺激的乳鼠心脏成纤维细胞,Ang II可上调miR-130a的表达。小鼠腹腔注射25 mg/kg miR-130a 抑制剂锁核酸(locked nucleic acid, LNA)-anti-miR-130a可显著抑制Ang II引起的心肌组织中miR-130a表达增加,改善Ang II引起心脏间质纤维化及舒缩功能障碍。转染miR-130a mimic可进一步促进Ang II引起的纤维化相关分子的表达增加以及肌成纤维细胞转化,miR-130a inhibitor则可抑制Ang II的上述作用。过表达PPAR-γ可抑制Ang II以及Ang II和miR-130a mimic联合应用引起的纤维化相关分子的表达。结论:miR-130a通过调控PPAR-γ的表达参与Ang II的促纤维化效应。
作者:李丽;张城林;赵茜;吴立玲 刊期: 2016年第08期
目的:探讨儿茶酚抑素( CST)对间歇低氧高血压大鼠的作用及机制。方法:健康雄性SD大鼠随机分为3组:control组、IH (间歇低氧组)组和IH+CST组(于低氧前3 d皮下埋植含CST 20 nmol? kg -1? d-1的微量渗透泵)。后2组置于间歇低氧舱中,舱内氧浓度为(5±0.5)%~(21±0.5)%,低氧-复氧循环时间为120 s(60 s+60 s),8 h/d,共3周。颈总动脉插管测收缩压(SP)、舒张压(DP)和平均压(MP),检测血浆中氧化/抗氧化损伤指标,Western blot 法检测主动脉和肾组织中核因子E2相关因子2(Nrf2)蛋白表达的变化。结果:SP、DP及MP,IH组均比control 组高(P<0.01),而IH+CST 组则显著低于IH 组(P<0.01)。 IH组的MPO和MDA含量显著高于control组(P<0.05),而SOD和羟自由基抑制率显著低于control组(P<0.01);IH+CST组的MPO和MDA明显低于IH组(P<0.05),SOD和羟自由基抑制率显著高于IH组(P<0.01)。与control组相比, IH组大鼠主动脉和肾组织胞浆、胞核中Nrf2蛋白的表达均显著下调(P<0.05);IH+CST组与IH组相比,胞浆中Nrf2蛋白的表达显著下调(P<0.05),而胞核中Nrf2蛋白的表达显著上调(P<0.05)。结论:CST有减轻间歇低氧致大鼠高血压的作用,该作用可能与其通过Nrf2-ARE信号通路调节氧化应激反应有关。
作者:陈然;范小芳;郑青青;丁露;薛峰;王永煜;龚永生 刊期: 2016年第08期
Angiotensin-converting enzyme 2 (ACE2)-angiotensin (1-7) [Ang (1-7)]-Mas constitutes the vasoprotective axis and is demon-strated to antagonize the vascular pathophysiological effects of the classical renin -angiotensin system .We hypothesize that upregulation of ACE2-Ang (1-7) signaling protects endothelial function through reducing oxidative stress , thus resulting in beneficial outcome in di-abetes.Ex vivo treatment with Ang (1-7) augmented endothelium-dependent relaxation (EDR) in renal arteries from diabetic patients . Both Ang (1-7) infusion via osmotic pump (500 ng? kg -1? min-1 ) for 2 weeks and exogenous ACE 2 overexpression mediated by ad-enoviral ACE2 via tail vein injection rescued the impaired EDR and flow-mediated dilatation ( FMD) in db/db mice.Diminazene acetu-rate treatment (15 mg? kg-1? d-1 ) activated ACE2, increased the circulating Ang (1-7) level, and augmented EDR and FMD in db/db mouse arteries.In addition, activation of the ACE2-Ang (1-7) axis reduced reactive oxygen species (ROS) overproduction de-termined by dihydroethidium staining , CM-H2DCFDA fluorescence imaging , and chemiluminescence assay in db/db mouse aortas and also in high-glucose-treated endothelial cells .Pharmacological benefits of ACE 2-Ang ( 1-7 ) upregulation on endothelial function were confirmed in ACE2 knockout mice both ex vivo and in vitro.We elucidate that the ACE2-Ang (1-7)-Mas axis serves as an important signal pathway in endothelial cell protection in diabetic mice , especially in diabetic human arteries .In summary, endogenous ACE2-Ang (1-7) activation or ACE2 overexpression preserves endothelial function in diabetic mice through increasing nitric oxide bioavail -ability and inhibiting oxidative stress , suggesting the therapeutic potential of ACE 2-Ang(1-7) axis activation against diabetic vasculop-athy.
作者: 刊期: 2016年第08期
目的:探讨omega-3多不饱和脂肪酸( polyunsaturated fatty acid , PUFA)对动脉粥样硬化斑块稳定性的作用及可能机制。方法:采用低密度脂蛋白受体敲除(Ldlr-/-)小鼠喂养西方饮食(western diet, WD)6周诱导动脉粥样硬化,并在饮食中添加或不添加3%omega-3 PUFA进行干预。使用液相质谱联用检测血浆中PUFA及其代谢产物浓度。油红O染色分析测定动脉树斑块面积及主动脉根部斑块脂质含量,HE染色分析主动脉根部斑块大小,天狼星红染色分析胶原纤维含量,免疫荧光检测巨噬细胞和平滑肌细胞含量。结果:(1)与WD组相比,omega-3组小鼠动脉树斑块面积比例显著降低。(2) Omega-3处理组与对照组相比,主动脉根部斑块面积、脂质含量和巨噬细胞含量显著降低;同时胶原纤维和平滑肌细胞含量显著上升,斑块不稳定指数下降(P<0.05)。(3)Omega-3处理组血清中omega-3 PUFA显著增加,分析代谢产物发现EEQ和18-HEPE水平显著增加。结论:Omega-3处理减少动脉粥样硬化斑块面积、增加斑块稳定性,其机制可能与其代谢产物水平变化相关。
作者:刘亚晋;李丹;张栩;艾玎;朱毅 刊期: 2016年第08期
AIM:MicroRNAs ( miRNAs) were recognized to play significant roles in cardiac hypertrophy .But, it remains unknown whether cyclin/Rb pathway is modulated by miRNAs during cardiac hypertrophy .This study investigates the potential roles of microRNA-1 (miR-1) and microRNA-16 (miR-16) in modulating cyclin/Rb pathway during cardiomyocyte hypertrophy .METHODS:An animal model of hypertrophy was established in a rat with abdominal aortic constriction (AAC).In addition, a cell model of hypertrophy was also achieved based on PE-promoted neonatal rat ventricular cardiomyocyte .RESULTS:miR-1 and-16 expression were markedly de-creased in hypertrophic myocardium and hypertrophic cardiomyocytes in rats .Overexpression of miR-1 and -16 suppressed rat cardiac hypertrophy and hypertrophic phenotype of cultured cardiomyocytes .Expression of cyclins D1, D2 and E1, CDK6 and phosphorylated pRb was increased in hypertrophic myocardium and hypertrophic cardiomyocytes , but could be reversed by enforced expression of miR-1 and -16.CDK6 was validated to be modulated post-transcriptionally by miR-1, and cyclins D1, D2 and E1 were further validated to be modulated post-transcriptionally by miR-16.CONCLUSION: Attenuations of miR-1 and -16 provoke cardiomyocyte hypertrophy via derepressing the cyclins D1, D2, E1 and CDK6, and activating cyclin/Rb pathway.
作者: 刊期: 2016年第08期
目的:观察胰腺β细胞中电导钙激活钾离子通道(intermediate-conductance Ca2+-activated K +channel, KCa3.1)在2型糖尿病发病中的作用及调节机制。方法:应用2型糖尿病小鼠(db/db)模型,测评阻断KCa3.1对2型糖尿病表型指标的影响。分离小鼠胰腺β细胞,观察分别阻断KCa3.1和NF-κB信号通路对高糖或软脂酸诱导的NF-κB下游炎性细胞因子释放的影响。结果:KCa3.1阻断剂TRAM-34可降低db/db小鼠随时血糖水平。连续用药8周后,TRAM-34可降低db/db小鼠空腹血糖,改善葡萄糖耐量,增加餐后胰岛素水平,减轻db/db小鼠胰腺炎症并延缓β细胞的消亡。但TRAM-34不影响正常饮食C57BL/6小鼠空腹血糖和餐后血糖水平,无低血糖副作用。在分离的小鼠胰腺β细胞,分别阻断KCa3.1和NF-κB可降低高糖或软脂酸所引起的炎性趋化因子(CCL2和CCL20)的释放。结论:NF-κB活化介导胰腺β细胞KCa3.1上调,协同调节炎性细胞因子和胰岛素分泌,促发胰岛炎症和β细胞功能障碍,导致2型糖尿病。
作者:庞正达;王晓静;佘刚;邓秀玲 刊期: 2016年第08期
AIM:Programmed necrosis ( necroptosis ) and apoptosis are crucially involved in multiple severe cardiac pathological conditions , including myocardial infarction, ischemia/reperfusion (I/R) injury, and heart failure.Whereas apoptotic signaling is well defined, the mechanisms underlying cardiomyocyte necroptosis remain elusive .METHODS AND RESULTS:Here we show that both mRNA and protein levels of receptor-interacting protein 3 (RIP3) in the hearts are increased by I/R injury and doxorubicin (Dox) treatment. In mice, RIP3 deficiency ameliorates myocardial necroptosis and heart failure induced by I /R (30-min ischemia/4-h or 8-week reper-fusion) or Dox treatment (20 mg/kg or 5 mg/kg ×4, i.p.).RIP3 overexpression induces cardiomyocyte necroptosis evidenced by de-creased intracellular ATP level and increased lactate dehydrogenase concentration in cell culture medium .RIP3 triggers myocardial ne-croptosis via activation of Ca2+/calmodulin-dependent protein kinase II (CaMKII), rather than the well-established RIP3 partners, RIP1 and MLKL (mixed lineage kinase domain-like protein).Specifically, our data indicate that I/R and Dox markedly activate myo-cardial CaMKII in wild-type but not RIP3-deficient mice , and that CaMKII inhibition or RIP 3 deficiency protect the heart from I/R-and Dox-induced cardiomyocyte necroptosis , cardiac remodeling and heart failure .Mechanistically , RIP3 activates CaMKII via both di-rect phosphorylation and indirect reactive oxidative species-dependent oxidation , and subsequently triggers opening of the mitochondrial permeability transition pore ( mPTP) and myocardial necroptosis .CONCLUSION: These findings identify CaMKII as a novel RIP 3 substrate and delineate a RIP3-CaMKII-mPTP myocardial necroptosis pathway , a promising target for the treatment of cardiac ischemic and oxidative damage , and heart failure .
作者: 刊期: 2016年第08期
目的:本研究拟探讨平滑肌蛋白22α( SM22α)对血管平滑肌细胞( VSMC)表面血小板源性生长因子受体β( PDGFR-β)胞吞的影响,进而揭示SM22α对PDGFR-β活性调控的关键步骤———胞吞和泛素化动态平衡的影响及其对血管重构过程的调控作用。方法:PDGF刺激体外培养大鼠VSMC,考察siRNA敲低SM22α蛋白后不同时点的细胞中,激光共聚焦显微镜观察PDGFR-β在细胞膜分布的异同;利用活细胞工作站实时观察SM22α的表达对PDGFR-β在细胞内内吞体和溶酶体分布的异同;SM22α对c-Cbl或TRAF6等E3泛素连接酶活性的影响;siRNA敲低早期内吞体标志蛋白Rab5、再循环内吞体标志蛋白Rab4和Rab11、多泡体( MVB)标志蛋白Rab7,观察SM22α对PDGFR-β亚细胞定位的变化及其与血管重构的关系。结果:研究发现,SM22α表达下调促进细胞表面的PDGFR-β的再循环过程,使PDGFR-β在细胞表面的分子数显著减少,激活信号分子Akt和p42/44磷酸化,促进PDGF诱导的VSMC生长、增殖和迁移过程,SM22α对PDGFR-β再循环的调控与血管重构过程密切相关。结论:PDGFR-β调控异常诱发的生物学行为改变是心血管疾病的主要细胞和分子生物学基础,我们的结果表明, SM22α可能通过影响PDGFR-β胞吞和泛素化动态平衡而影响其活性的调控,进而参与血管重构的病理生理过程,阐明其分子机制可为发掘基于影响PDGFR-β功能的心血管疾病药物设计提供新靶点。
作者:麻晓婷;窦永青;李晓坤;孟泽祺;韩梅;聂磊 刊期: 2016年第08期
目的:动物实验表明高盐摄入可降低循环及肾脏中肾胺酶的表达水平。本研究拟探讨钠、钾摄入对成人血清和尿中肾胺酶表达的影响。方法:42名(28~65岁)来自中国北方农村的受试者参与了这项研究。所有受试者依次接受低盐饮食7 d(氯化钠3 g/d),高盐饮食7 d(氯化钠18 g/d),高盐补钾饮食7 d(氯化钠18 g+氯化钾4.5 g/d)。血清及尿中肾胺酶水平用ELISA试剂盒进行检测。结果:低盐饮食期,血清中肾胺酶水平较基线期显著升高。低盐转向高盐饮食期时,血清肾胺酶水平随之下降,但同时给予补钾后,可阻止高盐所致的肾胺酶水平下降。尿中肾胺酶水平在高盐饮食期显著高于低盐期。高盐补钾期,尿中肾胺酶水平与单纯高盐期相比无显著差异,但显著高于低盐饮食期。24 h尿钠排泄与血清中肾胺酶水平呈负相关,与尿中肾胺酶水平呈正相关。结论:饮食中钠、钾含量的变化可显著影响中国人血清及尿中肾胺酶的表达水平。
作者:吕永波;汪洋;牟建军 刊期: 2016年第08期
AIM:We investigated how AT 1-R stimulated by mechanical stresses induces cardiac fibrosis .METHODS:We produced in vivo cardiac pressure overload model in angiotensinogen knockout ( ATG-/-) mice and in vitro mechanically-stretched cell model in cultured neonatal cardiac cells of ATG-/-mice both lack the participation of Ang II .RESULTS: Pressure overload for 4 weeks in ATG-/-mice induced myocardial hypertrophy accompanied by the significant interstitial fibrosis , however , the TGF-β, a key regulatory factor of fibrosis, was not significantly increased in these ATG-/-mice.Meanwhile, the inhibitor for AT1-R significantly inhibited mechani-cal stress-induced cardiac fibrosis in these ATG-/-models whereas inhibition of TGF-βdid not.CONCLUSION:The results showed that mechanical stress-induced fibrotic responses through AT 1-R required the phosphorylation of Smad 2 but not the involvement of TGF-β.
作者: 刊期: 2016年第08期
目的:建立大鼠心肌缺血再灌注损伤模型和氧化应激损伤细胞模型,研究抗肌萎缩蛋白Dp71在损伤心肌及细胞中的表达,探讨其拮抗心肌细胞凋亡的作用及其分子机制。方法:阻断SD大鼠冠状动脉左前降支血流30 min后恢复血流复制心肌缺血再灌注损伤模型,观察心肌形态学、LDH变化及心肌细胞凋亡;检测再灌注不同时间心脏Dp71蛋白和mRNA表达。建立H9c2细胞氧化应激损伤模型,检测H2 O2刺激后细胞中Dp71蛋白和mRNA的表达。 H9c2细胞转染Dp71过表达质粒,流式细胞术检测Dp71高表达对H2 O2诱导H9c2细胞凋亡率的影响。 Western blot检测过表达Dp71对细胞中lamin B1和Bcl-2蛋白表达的影响;对H2 O2刺激下lamin B1和Bcl2蛋白表达改变的影响。结果:与假手术组相比,再灌注损伤组HE染色心肌出现明显形态改变,LDH明显增加, IR组心肌细胞凋亡数显著增加。 IR后各时点Dp71 mRNA和蛋白表达水平均增加( P<0.05)。0.2 mmol/L H2 O2刺激细胞16 h Dp71蛋白及mRNA表达明显升高( P<0.05)。 H9c2细胞中转染Dp71过表达质粒可抑制H2 O2所诱导的细胞凋亡;H9c2细胞中过表达Dp71引起lamin B1和Bcl2表达增高,高表达的Dp71可以抑制过氧化氢刺激引起的lamin B1和Bcl2表达下降。结论:Dp71 mRNA和蛋白表达在大鼠心肌缺血再灌注损伤模型和H2 O2诱导H9c2氧化应激损伤模型中明显升高。 H9c2细胞过表达Dp71通过提高Bcl2和lamin B1表达而抑制H2 O2诱导的细胞凋亡。
作者:赵帅;邹江;刘梅冬;陈广文;王浩;余凤秀;肖献忠;谭斯品 刊期: 2016年第08期
目的:探讨NAD(P)H醌氧化还原酶1[NAD(P)H-quinone oxidoreductase 1,NQO1]过表达在卵巢黏液性囊腺癌临床预后评估中的意义。方法:应用免疫组化EnVision法检测NQO1蛋白在162例卵巢黏液性囊腺癌组织、35例卵巢黏液性囊腺瘤组织和29例正常卵巢上皮组织中的表达,并分析其过表达与卵巢黏液性囊腺癌临床病理学特点之间的关系,通过Kaplan-Meier方法进行生存分析。结果:NQO1蛋白在卵巢黏液性囊腺癌组织中的阳性率及强阳性率分别为85.8%和64.2%,显著高于卵巢黏液性囊腺瘤和正常卵巢上皮组织(P<0.01)。卡方检验结果显示,NQO1蛋白高表达与卵巢黏液性囊腺癌组织学分级和FIGO分期密切相关( P<0.05)。 Kaplan-Meier生存分析显示,NQO1蛋白高表达的卵巢黏液性囊腺癌患者总生存期和无病生存期均明显低于NQO1蛋白低表达患者。结论:NQO1蛋白在卵巢黏液性囊腺癌组织中呈高表达,可能成为卵巢黏液性囊腺癌预后评估的有效生物学指标。
作者:徐明;杨洋;车拴龙;朴英实;林贞花;陈丽艳 刊期: 2016年第08期
AIM:Increasing evidence suggests that carbohydrate-binding proteins play an essential role in tumor growth and metastasis .Ga-lectin-3, a multifunctional protein of an expanding family of β-galactoside-binding animal lectins , is the major nonintegrin cellular laminin-binding protein , and is implicated in a variety of biologic events , such as inflammation and angiogenesis .Because galectin-3 expression was shown to participate in mediating tumor angiogenesis and initiate signaling cascades in several diseases .We hypothe-sized that galectin-3 may promote pulmonary vascular endothelial neovascularization .METHODS:Hypoxic and MCT rat model of pul-monary artery remodeling was used .The mRNA and protein levels of galectin-3 in rats were measured by in situ hybrization and West-ern blot analysis.Endothelial cell (EC) proliferation, migration and tube formation were measured using MTT , cell scratch and Matri-gel assays, respectively.Protein expression was quantitated by Western blot analysis .LC 3A/B staining was detected with cellular im-munofluorescence staining .RESULTS:We found that galectin-3 was localized on the intima and adventitial wall .Galectin-3 was in-creased after rat hypoxia and MCT administration .Galectin-3 promoted EC proliferation , migration and tube formation , while its roles were reversed by RNA interference.Galectin-3 induced Atg 5, Beclin-1, LAMP-2, and LC 3A/B expression increases.Galectin-3 al-so increased LC 3A/B staining in ECs.Akt/mTOR and GSK-3βsignaling pathways were activated after galectin-3 treated ECs using its specific phosphorylation antibodies , while blocked it with LY294002 inhibited cell autophagy and EC dynamic alterations induced by galectin-3.CONCLUSION:These findings demonstrate that galectin-3 can induce an Akt signaling cascade leading to cell autoph-agy, and then the differentiation and angiogenesis of pulmonary artery endothelial cells .
作者: 刊期: 2016年第08期
AIM:Heart failure is characterized by immune activation leading to production and release of proinflammatory cytokines .Inter-leukin 17A (IL-17A) is a proinflammatory cytokine and multiple lines of evidence from animal and human studies suggest crucial roles of IL-17A in heart failure.Therefore, we investigated whether common polymorphisms of genes IL17A and IL17RA (coding interleukin 17 receptor A) gene contribute to genetic predisposition to heart failure and adverse clinical outcomes associated with it .METHODS AND RESULTS:A total of 1713 adults patients with congestive heart failure and 1713 age-and sex-matched controls were genotyped for promoter SNPs, rs2275913 and rs8193037 in IL17A and rs4819554 in IL17RA, to assess the relationship between individual SNPs and the risk of congestive heart failure .Results showed that rs8193037 in IL17A was associated with the risk of congestive heart failure (P<0.01) after adjustment for multiple cardiovascular risk factors including age , sex, smoking status, diabetes, hypertension and dyslipidemia.This association was evident in both ischemic and non-ischemic heart failure (P<0.05).Furthermore, prospective fol-low-up of 12.7 months for the occurrence of adverse clinical outcomes showed that rs 4819554 in IL17RA was significantly associated with cardiovascular mortality (P<0.05) after adjustments for multiple cardiovascular risk factors and New York Heart Association functional class.CONCLUSION:This study demonstrated associations of rs8193037 in the promoter of IL17A with the risk of conges-tive heart failure, and of rs4819554 in the promoter of IL17RA with the risk of cardiovascular mortality in patients with congestive heart failure.These data lend further support to the notion that immune activation and genetic polymorphisms contribute to heart failure path -ogenesis and progression .
作者: 刊期: 2016年第08期
目的:探讨高盐饮食对Dahl盐敏感大鼠肾小管上皮向间质转化( EMT )和肾脏纤维化的影响。方法:7~8周龄雄性Dahl盐敏感大鼠(SS, n=24)及SS-13BN大鼠(13BN, n=12),高盐、正常饮食干预4周与8周,测血压及血尿生化指标;用Masson染色评估肾脏纤维化程度;免疫组化和实时定量PCR检测肾小管上皮标志E-cadherin和间质细胞标志α-SMA mRNA和蛋白的表达情况。结果:(1)相较基线期,SS和13BN大鼠干预后收缩压增高,SS大鼠增高幅度更为明显;8周高盐干预时血压显著高于4周(P<0.01)。(2)4周高盐负荷后,2种大鼠肾脏均出现胶原纤维沉积,且SS高盐组多于13BN高盐组。8周时, SS高盐组肾小球和间质胶原沉积较4周进一步加重。(3)4周和8周高盐干预后,与SS正常饮食组相比,SS高盐组肾脏E-cadherin表达显著减少,α-SMA 表达明显增加。(4)肾脏纤维化程度与与肾小管EMT 的发生显著相关( E-cadherin: r =-0.787;α-SMA:r=0.866)。结论:高盐饮食可诱导Dahl盐敏感大鼠肾小管上皮细胞EMT的发生,促进肾脏纤维化。
作者:汪洋;牟建军;褚超;吕永波 刊期: 2016年第08期
目的:观察中电导钙激活钾离子通道(intermediate-conductance Ca2+-activated K +channel, KCa3.1)在软脂酸(palmitic acid, PA)诱导的单核细胞跨内皮迁移中的作用及其调控机制。方法:分离2型糖尿病(type 2 diabetes mellitus, T2DM)患者外周血单核细胞(peripheral blood mononuclear cells , PBMCs)并培养人单核细胞株(THP-1 cells),以PA刺激,通过Western blotting、RT-PCR、ELISA及细胞迁移实验观察PA对PBMCs及THP-1细胞跨内皮迁移的影响及其与KCa3.1的关系、KCa3.1与MCP-1之间的关系并探讨其信号转导通路。结果:100μmol/L PA上调体重指数(body mass index, BMI)位于20~27.9 kg/m2的T2DM患者PBMCs KCa3.1的表达并促进其跨内皮迁移,对BMI≥28 kg/m2的T2DM患者PBMCs无影响;KCa3.1特异性阻滞剂TRAM-34、NF-κB阻滞剂PDTC(100μmol/L)和Bay11-7082(10μmol/L)抑制PA诱导的BMI位于20~27.9 kg/m2的T2DM患者PBMCs跨内皮迁移;TRAM-34和KCa3.1特异性siRNA显著减少PA(200μmol/L)诱导的THP-1细胞跨内皮迁移及THP-1细胞中MCP-1的分泌和表达,anti-TLR2/4(4 mg/L)、p38MAPK抑制剂SB203580(10μmol/L)及 SB202190(10μmol/L)、PDTC(100μmol/L)和Bay11-7082(10μmol/L)显著减少PA诱导的THP-1细胞中KCa 3.1和MCP-1的表达。结论:PA通过TLR2/4-p38MAPK-NF-κB通路上调KCa3.1促进MCP-1的表达,进而诱导单核细胞的跨内皮迁移。
作者:马晓真;赵丽梅;庞正达;邓秀玲 刊期: 2016年第08期
AIM:To investigate the effect of miR-214 on cardiomyocyte hypertrophy and the expression of the potential target genes . METHODS:A cell model of hypertrophy was established based on angiotensin-Ⅱ( Ang-Ⅱ)-induced neonatal mouse ventricular car-diomyocytes (NMVCs).Dual luciferase reporter assay was performed to verify the interaction between miR-214 and the 3’ UTR of MEF2C.The expression of MEF2C and hypertrophy-related genes at mRNA and protein levels was determined by RT-qPCR and Wes-tern blotting, respectively.RESULTS:The expression of ANP, ACTA1,β-MHC and miR-214 was markedly increased in Ang-Ⅱ-in-duced hypertrophic cardiomyocytes .Dual luciferase reporter assay revealed that miR-214 interacted with the 3’ UTR of MEF2C, and miR-214 was verified to inhibit MEF2C expression at the transcriptional level .The protein expression of MEF2C was markedly in-creased in the hypertrophic cardiomyocytes .Moreover, miR-214 mimic, in parallel to MEF2C siRNA, inhibited the expression of hy-pertrophy-related genes in Ang-Ⅱ-induced NMVCs.CONCLUSION:MEF2C is a target gene of miR-214, which mediates the effect of miR-214 on attenuating cardiomyocyte hypertrophy .
作者: 刊期: 2016年第08期
目的:心肌肥厚是心脏对于压力负荷或者容量负荷所产生的适应性反应。细胞色素P450表氧化酶2J2(CYP 2J2)及其代谢产物EETs可以发挥抵抗心肌肥厚的作用,而其中的机制仍有待进一步探索。方法和结果:在体内研究中,我们采用PPARα缺陷小鼠以及野生小鼠为研究对象,并采用血管紧张素II( Ang II)诱导小鼠发生心肌肥厚。结果表明,Ang II可以明显诱导心肌肥厚,具体包括心脏肥大、心脏功能减低和心肌肥厚标志物表达增加。而在野生小鼠中,CYP 2J2过表达可以抑制Ang II所诱导的心肌肥厚,但是这一抑制作用在PPARα缺陷小鼠则没有体现。在离体研究中,我们以大鼠乳鼠心肌细胞作为研究对象并采用Ang II作为诱导因子。研究表明,外源性加入11,12-EET可明显抑制Ang II所诱导的心肌肥大,而PPARα特异性阻断剂GW6471可以阻断11,12-EET的作用,并且这一作用可能与Ras/MAPK以及NF-κB通路有关。另外,我们通过荧光报告基因系统以及染色质免疫沉淀实验证实, PPARα可以直接结合到caveolin-1的转录子区,并诱导caveolin-1的表达,而且采用siRNA介导caveolin-1的沉默,可以抑制11,12-EET抵抗Ang II的效应。结论:CYP 2J2及其代谢产物EETs可以通过PPARα缓解Ang II诱导的心肌肥厚,这一作用可能与其在转录水平上调caveolin-1的表达,并进一步抑制Ras/MAPK和NF-κB通路有关。
作者:赖金胜;陈琛;唐家荣;汪道文 刊期: 2016年第08期
目的:鸡尾酒疗法使得HIV阳性病人面对的临床挑战从免疫缺陷转移到心血管疾病等慢性疾病。然而,鸡尾酒疗法在生理性血管生长中的作用并不清楚。本文研究了鸡尾酒疗法骨干药物———核苷类逆转录酶抑制剂( NRTIs)对血管和淋巴管生成的影响。方法:利用体外细胞生长检测研究内皮细胞的凋亡、增殖和迁移,体内耳部和胶栓模型研究血管/淋巴管生成, Western blot检测信号通路,免疫荧光显微镜技术检测膜受体内吞。结果:药理浓度下,3种不同类型的NRTIs药物( TDF、AZT和3TC)在体内和体外都可以通过影响内皮细胞的增殖与迁移抑制血管和淋巴管生成。相对应的,NRTIs显著抑制了血管内皮中VEGFR2和FGFR1信号通路以及淋巴管内皮中VEGFR3信号通路,并且NRTI对受体酪氨酸激酶( RTK)信号通路的调控具有专一性。但是,3种NRTIs对RTK信号通路的负调控作用机制不同:AZT通过抑制RTK蛋白的成熟;而TDF和3TC则通过抑制RTK受体进入EEA1内吞小泡调控RTK的内吞。另一方面,我们发现NRTIs直接引起线粒体功能的紊乱,导致内皮细胞产生过量的线粒体来源ROS。线粒体ROS清除剂MnTMPyP可以有效逆转NRTIs导致的内皮细胞血管生成和淋巴管生成的功能障碍。结论:NRTIs引起细胞线粒体中产生过量的ROS,从而损伤内皮细胞的RTK信号通路,终负向调控血管生成和淋巴管生成。
作者:宋林;朱晓龙;裘聪;王月雯;赖蒽茵;孙益;Samson A.CHOW;余路阳 刊期: 2016年第08期