二苯乙烯苷对氧化诱导内皮细胞凋亡及Caspase-3和PARP表达的影响

为研究二苯乙烯苷对过氧化氢(H2O2)诱导人脐静脉内皮细胞凋亡的影响并初步探讨二苯乙烯苷抗凋亡的可能机制,采用不同浓度H2O2和二苯乙烯苷处理内皮细胞24 h,以MTT法检测细胞生长活力、Hoechst33258染色观察细胞形态、流式细胞仪检测凋亡率等方法筛选造模内皮细胞凋亡的H2O2浓度和二苯乙烯苷最佳的抗内皮细胞凋亡作用浓度.RT-PCR、Western-blot分别检测Caspase-3、PARP mRNA及蛋白质的表达.结果发现,与空白对照组相比,300μmol/L H2O2作用后,内皮细胞增殖明显受到抑制,Hoechst33258染色可见大量凋亡细胞,细胞凋亡率显著增加,流式细胞仪检测出明显的凋亡峰,Caspase-3和多聚腺苷酸二磷酸核糖基聚合酶(PARP)的表达量显著增加.经二苯乙烯苷处理后,随着二苯乙烯苷浓度增加,细胞的增殖率随之增加,凋亡细胞数减少,凋亡率逐渐降低,与H2O2组比较,10μmol/L的二苯乙烯苷能够显著提高细胞增殖率,降低细胞凋亡率,并显著减少Caspase-3和PARP表达.以上结果表明,二苯乙烯苷能够抑制由H2O2诱导的人脐静脉内皮细胞凋亡,增加细胞生长活性,降低细胞凋亡率,其作用机制可能与下调Caspase-3和多聚腺苷酸二磷酸核糖基聚合酶(PARP)的表达有关.     

截短型rhtBIGH3-(RGD)2蛋白通过上调miR-126 表达抑制 人脐静脉内皮细胞的生物活性

目的:探讨miR-126在截短型rhtBIGH3-(RGD)_2蛋白抑制HUVEC细胞生物学活性中的作用。方法:体外培养VEGF孵化的人脐静脉内皮细胞(VEGF-HUVEC),分别加入rhtBIGH3-(RGD)_2蛋白终浓度为0和100μg/mL,作用24、48、72 h条件下,分别检测Caspase-3活性和miR-126表达水平。在rhtBIGH3-(RGD)_2蛋白终浓度为0和100μg/mL时,分别加入miR-126 mimic和miR-126 inhibitor,作用VEGF-HUVEC 48 h后,Real-time PCR检测miR-126表达水平,通过检测Caspase-3活性来检测细胞凋亡情况。结果:在VEGF-HUVEC中,当rhtBIGH3-(RGD)_2蛋白终浓度为100μg/mL条件下,Caspase-3水平升高,miR-126表达水平升高,在48 h下达到最高峰。在VEGF-HUVEC中,当rhtBIGH3-(RGD)_2蛋白终浓度分别为100μg/mL条件下,加入miR-126mimic后,miR-126表达升高,Caspase-3水平升高;加入miR-126 inhibitor后,48 h后检测miR-126表达下降,Caspase-3水平也下降。结论:截短型rhtBIGH3-(RGD)_2蛋白通过上调miR-126表达从而促进细胞凋亡、抑制HUVEC生物活性,从而抑制角膜新生血管的发生     

夏枯草诱导人甲状腺乳头状癌细胞K1增殖和凋亡的影响及其作用机制

目的:探索夏枯草对人甲状腺乳头状癌细胞(K1)增殖和诱导K1细胞凋亡的影响及其可能的作用机制。方法:采用MTT比色法测定2~200 mg/mL夏枯草作用24 h对K1细胞增殖的影响;采用Hoechst染色法和流式细胞术(Annexin V-FITC/PI联合标记)观察0.3、0.6、1.2、2.4、4.8 mg/mL夏枯草作用24 h K1细胞凋亡的影响;采用蛋白质免疫印迹法(Western blotting)测定1.2、2.4、4.8 mg/mL夏枯草作用24h对K1细胞凋亡相关蛋白表达的影响。结果:在2~200 mg/mL的浓度范围内夏枯草作用24 h对K1细胞增殖有明显抑制作用(P0.05),IC50值为2.427 mg/mL。流式细胞术检测结果显示夏枯草可诱导K1细胞凋亡,2.4、4.8 mg/mL组K1细胞总凋亡率分别为(11.35±0.92)%、(44.57±3.07)%,与对照组相比明显升高(P0.05);与对照组相比,1.2、2.4、4.8 mg/mL夏枯草作用24 h胞浆内凋亡蛋白Bax、细胞色素C(Cyto C)、Caspase-9、活化的Caspase-3(Cleaved Caspase-3)表达增多。结论:夏枯草能抑制人甲状腺癌K1细胞增殖并诱导其凋亡,其机制可能与活化线粒体凋亡通路有关。     

CTSB 对人脐静脉血管内皮细胞系增殖及凋亡的影响

目的:探索组织蛋白酶B(CTSB)对人脐静脉血管内皮细胞系(HUVEC)增殖及凋亡的影响。方法:采用细胞转染法得到慢病毒空载体转染HU-MOCK细胞及CTSB过表达的HU-CTSB细胞,与正常的HUVEC细胞进行比较。采用MTT法检测HUVEC增殖情况;流式细胞仪检测各组细胞凋亡情况;采用蛋白免疫印迹法检测Bal-2/Bax及Caspase家族(Caspase-3/9)的表达情况。结果:HU-CTSB组各时间点HUVEC的增殖率明显低于其他两组,且差异具有统计学意义(P0.05);HU-CTSB组的HUVEC早期凋亡率(右下象限)和晚期凋亡率(右上象限)显著高于HUVEC组和HU-MOCK组,且组间差异具有统计学意义(P0.05);HU-CTSB组的抑制凋亡蛋白Bcl-2表达量明显低于其他两组,且促凋亡蛋白Bax表达量显著高于其他两组,差异均具有统计学意义(P0.05);HU-CTSB组caspases-3和caspases-9的活化片段显著高于其他两组,差异均具有统计学意义(P0.05)。结论:CSTB通过激活Caspase-3/9信号通路来上调Bax,并下调Bal-2,显著抑制HUVEC的增殖,并促进其凋亡,进而影响心血管疾病的发展。。     

枳实提取物及其药效组分对ox-LDL损伤的人脐静脉内皮细胞ICAM-1表达和NO释放的影响

目的:研究枳实提取物及其药效组分橙皮苷和新橙皮苷对氧化低密度脂蛋白(oxidized low density lipoprotein,Ox-LDL)损伤的人脐静脉内皮细胞(human umbilical vein endothelial cells line,HUVEC)细胞间黏附分子-1(intercellular adhesion molecule-1,ICAM-1)表达和一氧化氮(nitric oxide,NO)释放的影响。方法:体外培养HUVEC,50μg/mL ox-LDL制造HUVEC损伤模型。以MTS染色法检测细胞毒性确定用药浓度。细胞ELISA法测定细胞表面ICAM-1的含量,试剂盒测定细胞培养上清液中NO含量。结果:①枳实提取物小于等于2 mg/mL时,橙皮苷浓度小于等于0.03125 mg/mL时,新橙皮苷浓度小于等于0.25 mg/mL时,HUVEC存活率分别大于80%。②2.0 mg/mL和1.0 mg/mL两个浓度的枳实提取物、15.625μg/mL的橙皮苷和0.2500 mg/mL新橙皮苷对ox-LDL诱导的HUVEC的ICAM-1表达有显著抑制作用。③2.0 mg/mL枳实提取物显著提高ox-LDL诱导的HUVEC和正常HUVEC培养液中的NO含量;7.813μg/mL、15.625μg/mL和31.250μg/mL 3个浓度的橙皮苷能显著提高ox-LDL诱导的HUVEC培养液中的NO含量,31.250μg/mL的橙皮苷能促进正常HUVEC的NO释放;0.2500 mg/mL和0.1250 mg/mL 2个浓度的新橙皮苷能显著提高ox-LDL诱导的HUVEC培养液中的NO含量。结论:枳实提取物及其药效组分橙皮苷、新橙皮苷能抑制ox-LDL诱导的HUVEC的ICAM-1表达,促进ox-LDL诱导的HUVEC的NO释放。     

螺旋藻激酶对肾上腺素损伤内皮细胞分泌t-PA和PAI-1的影响

研究不同浓度螺旋藻激酶(spirulina kinase,SPK)对肾上腺素(Adr)损伤血管内皮细胞分泌组织型纤溶酶原激活物(t-PA)和纤溶酶原激活物抑制剂(PAI-1)的影响。采用不同浓度SPK处理人脐静脉内皮细胞(HUVEC),MTT法检测不同浓度SPK对HUVEC活力影响;建立Adr损伤模型,酶联免疫吸附法检测细胞培养液中t-PA和PAI-1含量的变化。结果显示SPK浓度在10μg/mL~2 mg/mL范围内,细胞活力明显升高且不影响细胞分泌t-PA和PAI-1的量;SPK作用于Adr损伤模型,各剂量组均可降低Adr损伤下HUVEC分泌PAI-1的量,提高t-PA/PAI-1比值。本研究揭示了SPK可通过降低PAI-1、提高t-PA/PAI-1比值来实现保护Adr损伤的血管内皮细胞。     

沙眼衣原体通过激活MAPK/ERK信号通路抑制宿主细胞凋亡

目的:研究沙眼衣原体抑制宿主细胞凋亡活性与MAPK/ERK信号通路的关系。方法:利用化学抑制剂U0126阻断MAPK/ERK信号通路,然后分别采用流式细胞术、Caspase-3活性检测试剂盒和Western Blot实验检测沙眼衣原体感染细胞在凋亡诱导剂Etoposide作用下细胞凋亡率和Caspase-3活性变化,以及PARP是否发生裂解。结果:当MAPK/ERK信号通路被阻断时,在Etoposide的作用下,沙眼衣原体感染细胞凋亡率明显上升,同时Caspase-3被活化和PARP发生裂解。结论:沙眼衣原体抑制宿主细胞凋亡活性与MAPK/ERK信号通路激活有关。     

脱氧胆酸钠在副溶血性弧菌死活细胞叠氮溴乙锭PCR鉴别中的应用

[目的]通过将表面活性剂脱氧胆酸钠(Sodium deoxycholate,SD)与叠氮溴乙锭(Ethidium bromide monoazide,EMA)-PCR反应体系相结合,建立SD-EMA-PCR鉴别副溶血性弧菌死活细胞的检测方法.[方法]依次对加入检测体系中的脱氧胆酸钠最适浓度、EMA区分死活细胞DNA的浓度范围、EMA激活光解最佳曝光时间进行优化;确定SD-EMA-PCR方法检测副溶血性弧菌死活细胞混合体系中活细胞的最低检出限.[结果]当脱氧胆酸钠浓度≤0.5 g/L,EMA的浓度为3.2-34.0 mg/L,曝光时间为25 min时,SD-EMA-PCR检测体系仅对死细胞DNA扩增产生抑制作用.SD-EMA-PCR检测活菌细胞的最低检出限为10 CFU/mL.[结论]死活细胞混合体系的SD-EMA-PCR检测证明该方法能够明显降低EMA-PCR漏检的死菌对检测结果造成的影响,为完善食源性致病菌检测中死活菌细胞鉴别方法提供了一种有效途径.     

左旋卡尼汀对脂多糖诱导小鼠肺微血管内皮细胞自噬和凋亡的影响*

目的:探讨左旋卡尼汀(LC)对脂多糖(LPS)损伤的小鼠肺微血管内皮细胞(PMVECs)的保护作用及自噬、凋亡的影响。方法:采用体外培养的小鼠PMVECs,分为对照组(Control组)、LPS组(10 μg/ ml,3、6、12、24 h)、LPS(10 μg/ ml,24 h)+LC(终浓度为2.5、5、10 μg/ml)(LC组)。Annexin V-FITC/PI双标记法检测细胞凋亡,细胞免疫荧光染色法检测自噬小体,Western blot法检测自噬相关蛋白LC3及凋亡蛋白Caspase-3的含量,CCK-8法检测细胞活力。结果:① 与Control组比较,LPS 6 h、12 h、24 h组PMVECs细胞活力显著受到抑制,细胞凋亡率、自噬蛋白LC3Ⅱ表达显著增高(P均＜0.01),LC3蛋白阳性表达。②与LPS 24 h组比较,各浓度LC组PMVECs细胞活力显著提高、自噬蛋白LC3II表达水平显著升高(P均＜0.01),而PMVECs凋亡率和凋亡蛋白Caspase-3表达水平均明显降低 (P＜0.05)。结论:LC具有提高LPS刺激的小鼠PMVECs活性、促进PMVECs自噬、抑制凋亡的作用。     

基于分子对接的合欢皂苷J_(8)抑制血管内皮细胞增殖作用靶点及其凋亡相关细胞信号通路研究CSCD

为探讨合欢皂苷J_(8)(julibroside J_(8),J8)抑制肿瘤血管内皮细胞增殖作用靶点及其相关细胞凋亡的信号通路。本文采用HPLC法检测内皮细胞经J8作用后,J8的在细胞内外含量变化;Vina软件将J8与VEGF、FAS、DR3、DR4、DR5、TFR-1进行分子对接分析;Western blot法检测在加药前后,内皮细胞中VEGF、p-JNK、Bax、EnDOG、Caspase-3、Caspase-8以及Caspase-9蛋白表达水平的变化。分子对接结果表明VEGF、FAS对应的靶点蛋白与J8结合性能较好且多位点结合。HUVEC细胞在加入J8作用24 h后,VEGF、p-JNK等蛋白表达明显下调,并可显著上调诱导凋亡相关蛋白Bax和EnDOG的表达,而且对Caspase-3、Caspase-8以及Caspase-9的表达水平无显著的影响。J8可能是通过与血管内皮细胞膜表面的VEGF结合,抑制血管内皮细胞增殖,通过削弱VEGF/JNK通路活性从而引起内皮细胞凋亡。     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

鸡传染性法氏囊病病毒研究进展

传染性法氏囊病(Infection bursal disease, IBD)是由鸡传染性法氏囊病毒(Infectious bursal disease virus, IBDV)引起的鸡和火鸡的一种高度接触性传染病,给世界各国的禽养殖业带来了巨大损失.自IBDV发现至今新的变异株不断出现,分子结构的改变导致病毒致病力的改变及宿主对疫苗应答的改变,使得传统的疫苗已不能控制其流行,因此各国学者对其基因组结构和功能进行了广泛深入的研究,并积极研制新型有效的疫苗以达到防治的目的.     

Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).     

Enterovirus 71 3C proteolytically processes the histone H3 N-terminal tail during infection

Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.