简介:Apoptosisisprimarilyexecutedbyactivecaspases,whicharederivedfromtheinactiveprocaspasezymogensthroughproteolyticcleavage.Wedeterminedthecrystalstructuresofacaspasezymogen,procaspase-7,andanactivecaspase-7withoutanyboundinhibitors.Comparedtotheinhibitor-boundcaspase-7,procaspase-7zymogenexhibitssignificantstructuraldifferencessurroundingthecatalyticcleft,whichprecludestheformationofaproductiveconformation.Proteolyticcleavageinbetweenthelargeandsmallsubunitsallowsrearrangementofessentialloopsintheactivesite,primingactivecaspase-7forinhibitor/substratebinding.Strikingly,bindingbyinhibitorscausesa180-degree-flippingoftheN-terminusinthesmallsubunit,whichinteractswithandstabilizesthecatalyticcleft.Theseanalysesrevealthestructuralmechanismsofcaspaseactivationanddemonstratethattheinhibitor/substratebindingisaprocessof
简介:目的建立海水浸泡颅脑挫裂伤模型,观察海水浸泡对实验性脑挫裂伤后创伤性脑水肿的影响及研究兔脑挫伤后不同时间caspase-8及caspase-3表达的变化。方法采用立体定向自由落体伤模型进行持续海水浸泡作为实验组,对照组采用同样的方法致伤后不进行海水浸泡。观察创伤组织的病理改变,并通过免疫组化染色和计算机图像分析技术用半定量化的方法检测不同干预不同时程caspase-8和caspase-3的活性表达强弱差异。结果实验组和对照组均发生了创伤性脑水肿.但水肿高峰期出现时间不一致,严重程度也不一致。实验组caspase-8和caspase-3活性表达强度均高于对照组。结论海水浸泡促进了挫裂伤周边缺血水肿区神经细胞凋亡的增加。
简介:目的人胃癌组织中caspase-3表达的研究。探讨caspase-3表达-9胃癌预后的关系。方法应用免疫组织化学ABC法检测人胃癌组织中caspase-3的表达情况。结果周围正常胃粘膜上皮caspase-3阳性率为94/99(94.9%),胃癌组织中caspase-3的阳性率为62/99(63.5%),较周围正常胃粘膜上皮明显降低(P〈0.05)。caspase-3的表达与胃癌的预后指标(如组织学类型,TNM分期等)明显相关性。结论人胃癌组织中caspase-3的表达较低。这一结果提示caspase-3低表达导致的细胞凋亡异常降低及增生过度可能是胃癌的发病原因之一。这一结果亦提示caspase-3与胃正常粘膜及肿瘤细胞的凋亡有关。Caspase-3可能是胃癌的预后指标之一。
简介:IAPs(inhibitorsofapoptosis)areafamilyofproteinscontainingoneormorecharacteristicBIRdomains.Theseproteinshavemultiplebiologicalactivitiesthatincludebindingandinhibitingcaspases,regulatingcellcycleprogression,andmodulatingreceptor-mediatedsignaltransduction.OurrecentstudiesfoundtheIAPfamilymembersXIAPandc-IAP1areubiquitinatedanddegradedinproteasomesinresponsetoapoptoticstimuliinTcells,andtheirdegradationappearstobeimportantforTcellstocommittodeath.InadditiontothreeBIRdomains,eachoftheseIAPsalsocontainsaRINGfingerdomain.Wefoundthisregionconfersubiquitinproteaseligase(E3)activitytoIAPs,andisresponsiblefortheauto-ubiquitinationanddegradationofIAPsafteranapoptoticstimulus.GiventhefactthatIAPscanbindavarietyofproteins,suchascaspasesandTRAFs,itwillbeofinteresttocharacterizepotentialsubstratesoftheE3activityofIAPsandtheeffectsofubiquitinationbyIAPsonsignaltransduction,cellcycle,andapoptosis.
简介:摘要:目的:探讨中药烧伤膏对糖尿病并发皮肤溃疡小鼠创面抑制细胞凋亡作用及机理。方法:SPF级小鼠雄性40只,(STZ)诱导成模,将造模成功的糖尿病小鼠随机分为4组,每组10只;分别为模型组、湿润烧伤膏组)、康复新液照组、空白组,采用IHC法检测caspase3、caspase8的蛋白表达结果:湿润烧伤膏组,康复新液组溃疡面愈合量的比率明显优于模型组对照组(p
简介:AIM:Toevaluatetheroleofsurvivinandcaspase-3inapoptosisofgastriccarcinoma,aswellasinprognosisofpatientswithgastriccarcinoma.METHODS:Expressionsofsurvivinandcaspase-3wereinvestigatedimmunohistochemicallyin80gastriccarcinomapatientswithoutahistoryofchemo-radiationtherapy.TumorcellapoptosiswasexaminedbyTUNELmethod.RESULTS:Immunohistochemicalanalysisshowedthatsurvivinexpressionwaspositivein61of80patients(76%)withgastriccarcinoma.Incontrast,noexpressionofsurvivininadjacentnormaltissueswasdetected.Expressionlevelofcaspase-3washigherinnormaltissuesthanincarcinoma.Patientswithhigherexpressionofsurvivinhadworsehistologicalgradesandpathologicalstages.Expressionofcaspase-3wassignificantlyassociatedwithhistologicalstages,butnotwiththepathologicalstages.Althoughsurvivinexpressionincarcinomawasnotinverselyrelatedtocaspase-3,patientswithsurvivin(-)andcaspase-3(+)hadthemaximumapoptosisindex.CONCLUSION:Expressionlevelofsurvivinwasassociatedwithhistologicalgradesandpathologicalstagesofthetumor,indicatingthatsurvivinmaybeapoorprognosisfactorforgastriccarcinoma.Unlikecaspase-3,survivin(anapoptosisinhibitor)canmarkedlyinhibittheapoptosisoftumorcells.
简介:摘要目的探讨Caspase-3、Caspase-9、Bcl-2蛋白对骨质疏松症发病机理的影响。方法收集20例患者(骨质疏松症组、正常组各10例)髋关节置换手术中取下股骨头或股骨颈中松质骨,分别进行成骨细胞体外培养,通过ELISA方法检测正常人和骨质疏松症患者成骨细胞中Caspase-3、Caspase-9、Bcl-2蛋白表达情况。结果对比于正常组,骨质疏松症组中Caspase-3、Caspase-9的表达较正常组增高,差异有统计学意义(P<0.05),而Bcl-2表达水平在骨质疏松症组中较正常组下降,差异亦有统计学意义(P<0.05)。结论在骨质疏松症的成骨细胞凋亡过程中,Caspase依赖性凋亡途径激活,而Bcl-2途径受到抑制。
简介:Apoptosismanifestsintwomajorexecutionprogramsdownstreamofthedeathsignal:thecaspasepathwayandorganelledysfunction.Animportantantiapoptosisfactor,Bcl-2protein,contributesincaspasepathwayofapoptosis.Calcium,animportantintracellularsignalelementincells,isalsoobservedtohavechangesduringapoptosis,whichmaybeaffectedbyBcl-2protein.WehavepreviouslyreportedthatinHarringtonine(HT)inducedapoptosisofHL-60cells,there'schangeofintracellularcalciumdistribution,ovingfromcytoplastespeciallyGolgi'sapparatustonucleusandaccumulatingtherewiththehighestconcentration.Wereportherethatcaspase-3becomesactivatedinHT-inducedapoptosisofHL-60cells,whichcanbeinhibitedbyoverexpressionofBcl-2protein.NosignofapoptosisorintracellularcalciummovementfromGolgi'sapparatustonucleusinHL-60cellsoverexpressingBcl-2ortreatedwithAc-DEVD-CHO,aspecificinhibitorofcaspase-3.Theresultsindicatethatactivatedcaspase-2canpromotethemovementofintracellularcalciumfromGolgi'sapparatustonucleus,andtheprocessisinhibitedbyAc-DEVD-CHO(inhibitorofcaspase-3),andthatBcl-2caninhibitthemovementandaccumulationofintracellularcalciuminnucleusthroughitsinhibitiononcaspase-3.Calciumrelocalizationinapoptosisseemstobeirreversible,whichisdifferentfromtheintracellularcalciumchangescausedbygrowthfactor.
简介:摘要目的 :注射 Kainate诱导的大鼠边缘叶发作模型 .检测 caspase-12大鼠海马神经元表达。方法:立体定位海马注射 Kainate诱导诱导激活海马内的 KAI受体后,以持续记录脑电、局部脑血流( rgional cerebral blood flav, rCBF),用 TUNEL染色和 ciesyl violet染色观察海马神经元存活和凋亡;用免疫荧光和 Western blot检测海马 caspast-12的表达。结果: 4h时 caspase-12出现裂解片段, 8h时出现 TUNEL阳性细胞, 24h时达高峰。脑室内注射 caspase-12抑制剂 zrLEHrHluoKmettylketoneCzrLEHDfmk)可减少 TUNEL阳性细胞,增加存活神经元;后在 KA注射同侧海马的 CA3区神经元 caspasd免疫反应性增强;对侧海马未见 TUNEL阳性细胞及 caspase-12的上述变化。发作前后 rCBF无明显变化。结论: Kainate可诱导 KAI的激活。 caspase-12可能是 KAI的靶点,也可能是神经元损伤的潜在靶点。
简介:BCL-2 蛋白家族与细胞凋亡.细胞生物学杂志 2001,Caspase家族与细胞凋亡调控,Caspase家族与细胞凋亡
简介:摘要目的研究Ndfip1保护PD细胞模型过程中对Caspase9及Caspase3活性的影响;初步探讨Ndfip1对PD细胞模型保护作用的机制。方法在以往工作基础上,采用MPP+诱导培养的人神经母细胞瘤SH-SY5Y细胞模型作为研究对象,通过MTT、WesternBlotting等方法研究Ndfip1对MPP+诱导的PD细胞模型保护作用过程中对Caspase9及Caspase3活性的影响。结果Ndfip1的表达可保护帕金森病细胞模型,减少细胞凋亡,同时引起Cascase-9及Caspase-3的活性降低。结论过表达Ndfip1可能对PD细胞模型的凋亡起抑制作用,能有效的减少凋亡细胞的数目,对神经细胞有一定的保护作用,Ndfip1的这种神经保护作用的机制可能涉及降低Cascase-9及Caspase-3的活性。
简介:摘要目的研究caspase-3表达在胃癌发生发展中的作用。方法采用免疫组化S-P法观察113例胃癌旁上皮细胞、原发灶癌细胞和浸润淋巴细胞以及转移灶癌细胞中caspase-3表达,TUNEL法检测上述组织的细胞凋亡,并分析原发灶癌细胞中caspase-3表达与胃癌临床病理特征的关系,并探讨caspase-3表达与细胞凋亡的关系。结果caspase-3在50.4%(57/113)的胃癌旁上皮细胞中表达,高于原发灶癌细胞中的阳性率32.7%(37/113)(P<0.05);caspase-3在胃癌原发灶浸润淋巴细胞中的阳性率为70.8%(80/113),高于胃癌旁上皮细胞和原发灶癌细胞中阳性率(P<0.05);58.1%(25/43)的转移灶癌细胞中caspase-3表达阳性,其阳性率高于对应原发灶癌细胞(34.2%,13/38)(P<0.05);原发灶癌细胞中caspase-3表达与胃癌患者的年龄、性别以及胃癌肿瘤大小、浸润深度、转移、TNM分期、生长方式和分化程度无相关性(P>0.05)。原发灶癌细胞和浸润淋巴细胞及转移灶癌细胞中细胞凋亡指数明显低于癌旁上皮细胞(P<0.01)。结论胃癌原发灶癌细胞中caspase-3表达下调和浸润淋巴细胞中caspase-3表达上调与胃癌发生有关,由caspase-3介导的细胞凋亡与胃癌的发生与发展有关。
简介:BACKGROUND:Studieshavedemonstratedthatthemechanismsunderlyingcellularapoptosissignaltransductionfocusontwopathways:intracellularmitochondriaandextracellulardeathreceptor.Thecurrentevidencesupportsthatsignaltransductionofcellularapoptosisalsoincludesendoplasmicreticulumstresssignaltransduction.OBJECTIVE:ToobserveCaspase-12expressionandcellularapoptosisfollowingischemiainratswithprogressivespinalcordcompression,andtoverifytheinfluenceofendoplasmicreticulumstressontheapoptosisinducedbyspinalcordinjury.DESIGN,TIMEANDSETTING:Arandomized,controlled,animaltrialwasperformedattheInstituteofNeuroscienceinChongqingMedicalUniversitybetweenJanuaryandOctoberin2006.MATERIALS:Immunohistochemicalkit,diaminobenzidine,andTUNELkitwerepurchasedfromBeijingZhongshanBiotechnology,China;rabbitanti-ratCaspase-12monoclonalantibodywasprovidedbySantaCruz,USA.METHODS:SixtyWistarrats,aged3-4months,wererandomlyassignedtoamodelgroup(n=50),whichunderwentspinalcordcompressionintheL_1segmentfollowingL_1laminectomyandarticularprocessexcisiontoestablishamodelofprogressivespinalcordcompression,andasham-surgerygroup(n=10),whichunderwentonlylaminectomy.Startingwiththefirstdayaftersurgery,theratswerelocallyanesthetized,theskinwasopened,andthescrewwasrotatedby1/4ofacycle,twiceweekly.MAINOUTCOMEMEASURES:At3,7,14,21,and28daysaftersurgery,ratsfromeachgroupwereanesthetized,andthespinalcordswereresected.Pathologicalchangesfollowingspinalcordcompressionweredeterminedusinghematoxylin-eosinstaining,Nissldye,andtransmissionelectronmicroscopy.TheTUNELmethodwasusedtoobserveneuronalapoptosisinthecompressedspinalcordsegments.ImmunohistochemistryandWesternblotwereutilizedtodetectCaspase-12expressioninthecompressedsegments.RESULTS:Cellularswelling,neuraldegeneration,andalteredendoplasmicreticulumstructureswereobservedat3days
简介:目的探讨姜黄素诱导雄激素依赖性前列腺癌LNCaP细胞凋亡过程中caspase途径的作用。方法应用CCK8法检测不同浓度(10、20、30、40、50、60μmol/L)姜黄素作用LNCaP细胞12、24、48h后的细胞生长抑制情况。应用AnnexinV/PI双染法检测不同浓度(10、20、40μmol/L)姜黄素作用LNCaP细胞24h后的细胞凋亡情况。应用Westernblot检测姜黄素作用LNCaP细胞24h后Bax、Bcl-2、Cleaved-caspase-3、CytochromeC凋亡相关蛋白的变化。结果姜黄素对LNCaP细胞的生长有明显的抑制作用,且呈时间-剂量依赖性;流式细胞术结果显示姜黄素能诱导LNCaP细胞凋亡,10、20、40μmol/L姜黄素作用LNCaP细胞24、48h后细胞凋亡率分别为(6.01±0.95)%、(15.46±1.13)%、(26.13±1.56)%和(11.19±1.74)%、(25.80±2.47)%、(38.72±2.89)%,且呈时间-剂量依赖性(P〈0.05);同时姜黄素能够降低LNCaP细胞中Bcl-2的表达,上调Bax、CytochromeC、Cleavedcaspase-3的表达。结论姜黄素能抑制LNCaP细胞的生长,其作用可能是通过线粒体途径诱导其凋亡。