肿瘤抑制剂GA对SH-SY5Y细胞凋亡的影响及分子机制研究

为了探讨HSP90特异的功能抑制剂geldanamycin(GA)能否用于神经母细胞瘤的临床治疗 ,通过检测未分化的和全反式维甲酸 (RA)诱导分化的神经母细胞瘤SH SY5Y细胞在不同浓度GA处理后的细胞存活率 ,发现GA呈剂量依赖性诱导SH SY5Y细胞凋亡 ,但是分化细胞对同样剂量的GA不是很敏感 [细胞存活率依次为 (82 0±6 0 ) %比较 (6 5 0± 3 0 ) % ,P <0 0 2 ;(6 7 9± 3 1) %比较 (4 3 4± 3 9) % ,P <0 0 3;(4 3± 0 8) %比较 (0 4±0 1) % ,P <0 0 5 ]。Western印迹分析和免疫荧光实验显示 ,GA能抑制细胞中c Jun和c Fos的表达 ,并且GA剂量越高 ,其抑制越明显 ;同时GA也诱导了p5 3的核聚集。与未分化细胞相比 ,在相同剂量GA处理后分化细胞中c Jun和c Fos的表达均比未分化细胞略高 ;但是分化细胞中p5 3的核聚集却不如前者明显。提示未分化细胞对同样剂量的GA比分化细胞更敏感 ,可能与分化细胞能抵抗GA引起的c Jun、c Fos的降低以及p5 3的核聚集有关。     

胞外高浓度ATP诱导SH-SY5Y细胞的自噬和凋亡

目的：观察胞外高浓度ATP损伤人神经母细胞瘤SH-SY5Y细胞的作用,探讨损伤中自噬和凋亡发生的规律和特点。方法：培养的SH-SY5Y细胞按照加入ATP的浓度和作用时间进行分组。CCK-8法检测细胞生存率,单丹磺酰戊二胺染色检测自噬空泡的变化,Hoechst33258染色检测细胞凋亡,流式细胞术检测细胞凋亡率变化,蛋白质印迹法检测半胱氨酸天冬氨酸蛋白酶3（caspase-3）及微管相关蛋白1轻链3-Ⅱ（microtubule-associatedprotein1lightchain3-Ⅱ,LC3-Ⅱ）的表达。结果：（1）与对照组相比,不同浓度（3、6、9、12、15mmol/L）的ATP作用3h均使SH-SY5Y细胞存活率明显降低,且呈剂量依赖性;不同作用时间（1、2、3、6h）ATP（6mmol/L）也可使SH-SY5Y细胞存活率明显降低,3h达高峰,呈时间依赖性。（2）ATP作用1h时SH-SY5Y细胞自噬空泡显著增多（P<005）,随时间延长,6h时降到对照水平;ATP作用1h时,LC3-Ⅱ表达显著增强（P<005）,形成高峰,与自噬空泡增多的时点重合,2h、3h时LC3-Ⅱ表达水平逐渐减弱,6h时降到对照水平。（3）与对照组相比,ATP作用3h后细胞凋亡率达高峰（P<005）,6h时仍然保持在3h的水平;cleavedcaspase-3表达量同步增强（P<005）,6h时达高峰。结论：胞外高浓度ATP能够诱导SH-SY5Y细胞自噬和凋亡;自噬增强在前,凋亡高潮在后;随着ATP作用时间的延长,凋亡占主导地位。     

利多卡因对SH-SY5Y细胞的损伤作用

目的:采用SH-SY5Y细胞体外培养模型,通过观察细胞形态、测定细胞活力和细胞凋亡率,探讨不同浓度利多卡因对SH-SY5Y细胞的损伤作用。方法:SH-SY5Y细胞离体培养,分为4组,即:正常培养组(对照组,未经药物处理);0.5%、1%、2%利多卡因组(L1、L2、L3组),分别用相应浓度的利多卡因处理SH-SY5Y细胞10min。在药物处理10min后观察细胞形态,并分别在药物处理后5min(T1)、10min(T2)、药物处理结束后15min(T3)、药物处理结束后12h(T4)测定细胞活力及细胞凋亡率。结果:正常培养SH-SY5Y细胞胞体粗大,呈多角形,出现树突状突起,神经突起,多而粗大,分布成网络,各实验组SH-SY5Y细胞则变圆,回缩,轴突渐消失。各实验组不同浓度的利多卡因对SH-SY5Y细胞活力均有明显影响,利多卡因处理5min后,各组细胞活力明显下降,且随剂量增加,细胞活力下降明显增加。对照组细胞凋亡率在各时点保持在5.9%~6.3%之间,实验组细胞在利多卡因处理后各时点细胞凋亡率明显增加,且随着浓度的增加,细胞凋亡率也增加。结论:0.5%、1%、2%利多卡因对SH-SY5Y细胞均有损伤作用,且随浓度的增加,损伤程度加重。     

miR-449a过表达抑制人神经母细胞瘤细胞SH-SY5Y增殖并促进其凋亡

目的探讨miR-449a对人神经母细胞瘤细胞系SH-SY5Y的增殖和凋亡的影响。方法用Lipofectamine TM2000将miR-449a模似物或miR-449a对照转染至SH-SY5Y细胞,分为空白、miR-449a模似物和miR-449a对照SHSY5Y细胞组;实时荧光定量PCR(q-PCR)检测各组细胞中miR-449a表达;CCK8法检测细胞增殖;流式细胞仪检测细胞凋亡和周期,Western blot检测c-Myc蛋白和Bax/Bcl-2蛋白表达。结果 miR-449a模似物瞬时转染SH-SY5Y细胞后,miR-449a的表达水平明显高于正常对照组(P0.05);SH-SY5Y细胞增殖能力受到明显抑制(P0.05);凋亡率明显增加(P0.05);c-Myc蛋白表达显著降低(P0.05);细胞促凋亡蛋白Bax表达升高;抗凋亡蛋白Bcl-2表达降低(P0.05)。结论 miR-449a可通过c-Myc影响SH-SY5Y细胞的增殖和周期,通过调节Bax/Bcl-2影响其凋亡。     

灵孢多糖对过氧化氢致SH-SY5Y细胞凋亡及线粒体功能障碍的调控

背景：目前研究证实,灵孢多糖可促进神经退行性相关疾病的神经再生。神经退行性疾病的发生与线粒体功能失调密切相关,但灵孢多糖对神经退行性疾病的细胞凋亡及线粒体功能的调控作用尚不明确。目的：探索灵孢多糖对过氧化氢诱导的SH-SY5Y细胞凋亡及线粒体功能障碍的调控作用及机制。方法：SH-SY5Y细胞分为3组：对照组,过氧化氢组,灵孢多糖组。对照组细胞正常培养,过氧化氢组细胞用300μmol/L过氧化氢处理24 h,灵孢多糖组先用300μg/μL灵孢多糖干预一两个小时,然后加入300μmol/L过氧化氢干预24 h,干预结束后用JC-1试剂盒检测线粒体膜电位,TUNEL染色试剂盒检测细胞凋亡情况,丙二醛试剂盒和超氧化物歧化酶试剂盒检测丙二醛和超氧化物歧化酶活性,免疫荧光染色法和Western blot法检测凋亡、线粒体动力学相关蛋白的表达。结果与结论：(1)与对照组相比,过氧化氢组线粒体膜电位和超氧化歧化酶活性显著降低,细胞凋亡率、丙二醇水平显著增高,差异均有显著性意义(P <0.05);与过氧化氢组相比,灵孢多糖组线粒体膜电位和超氧化歧化酶活性显著增高,细胞凋亡率、丙二醛水平显著下降,差...     

依达拉奉通过microRNA-25抑制高糖诱导的SH-SY5Y细胞凋亡

目的:探讨依达拉奉通过微小RNA-25(microRNA-25,miR-25)对高糖诱导的人神经母细胞瘤SHSY5Y细胞凋亡的抑制作用及其机制。方法:将SH-SY5Y细胞用含高浓度葡萄糖的DMEM培养基和依达拉奉的联合培养液共同培养24 h。MTT比色法测定SH-SY5Y细胞存活率;DCFH-DA荧光探针法检测SH-SY5Y细胞中活性氧簇(ROS)的水平;采用流式细胞术检测SH-SY5Y细胞的凋亡率;Western blot法检测凋亡相关蛋白Bax和Bcl-2的表达水平;实时定量PCR检测细胞中miR-25的表达水平。为进一步阐明依达拉奉抑制高糖诱导的神经细胞凋亡的作用靶点,我们将miR-25抑制剂应用于细胞,之后采用caspase-3凋亡试剂盒检测细胞的凋亡率。结果:与对照组相比,高糖诱导后细胞存活率明显降低,细胞中的ROS水平和细胞凋亡率明显升高,Bax的表达明显增加,Bcl-2的表达明显降低,miR-25的表达水平也明显降低。给予依达拉奉治疗之后,细胞存活率明显升高,ROS含量和细胞凋亡率明显降低,Bax的蛋白水平明显降低,Bcl-2蛋白水平明显升高,miR-25的表达水平亦明显升高。进一步给予miR-25抑制剂后,caspase-3的水平明显升高,此时同时给予依达拉奉后并不能抑制高糖引起的神经细胞的凋亡。结论:依达拉奉对高糖诱导的SH-SY5Y细胞凋亡具有抑制作用,其作用靶点可能是miR-25。     

圣草酚对过氧化氢所致SH-SY5Y细胞线粒体动力学失衡及凋亡的影响

背景：线粒体动力学异常与神经退行性疾病中氧化应激现象密切相关。课题组前期研究发现圣草酚可以减轻阿尔茨海默病神经损伤,但其是否对线粒体动力学有调控作用尚未明确。目的：探讨圣草酚抑制过氧化氢诱导的SH-SY5Y细胞凋亡的具体机制。方法：将SH-SY5Y细胞分为如下3组：PBS对照组、过氧化氢(250 μmol/L)模型组、过氧化氢(250 μmol/L)+圣草酚治疗组(10 μmol/L)。干预24 h,应用试剂盒检测丙二醛水平和超氧化物歧化酶活性,显微镜下观察细胞形态,TUNEL染色观察细胞凋亡情况,JC-1染色观察线粒体膜电位,免疫荧光染色法和Western blot检测细胞凋亡蛋白以及线粒体融合和线粒体分裂蛋白的表达。结果与结论：①与过氧化氢组相比,圣草酚治疗组丙二醛水平显著减少,超氧化物歧化酶活性显著增加;②与PBS对照组相比,过氧化氢组细胞密度下降,胞体肥大,细胞凋亡率增加,线粒体模电位下降,Bcl-2表达减少,Bax表达增加;与过氧化氢组相比,圣草酚治疗组上述指标得到明显改善;③与PBS对照组相比,过氧化氢组细胞线粒体分裂相关蛋白p-DRP1和FIS1的表达量升高,而线粒体融合相关蛋白OPA1和Mfn2的表达量降低;与过氧化氢组相比,圣草酚治疗可以降低p-DRP1和FIS1的表达,增加OPA1和Mfn2的表达;④结果说明,圣草酚可通过调控线粒体动力学抑制过氧化氢诱导的SH-SY5Y细胞凋亡。https://orcid.org/0000-0003-0049-1658 (马存根)中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程     

Bcl-xl基因克隆及其在SH-SY5Y细胞中的表达

目的研究Bcl-xl基因在SH-SY5Y细胞中的表达。方法构建真核表达载体pIRES2-EGFP/Bcl-xl,采用脂质体介导将重组质粒导入SH-SY5Y细胞,RT-PCR和Western-blot检测外源基因表达。结果本实验成功构建了真核表达载体pIRES2-EGFP/Bcl-xl,并用脂质体介导的方法高效转染SH-SY5Y细胞,RT-PCR显示有Bcl-xlmRNA表达增加,Western-blot显示有32kD的蛋白质表达增加。结论重组质粒pIRES2-EGFP/Bcl-xl经转染能够在SH-SY5Y细胞中高效表达,为进一步研究Bcl-xl对SH-SY5Y细胞的生物学功能奠定了基础。     

DADLE对SH-SY5Y细胞缺氧复氧损伤的保护作用

目的:探讨[D-Ala2,D-Leu5] enkephalin (DADLE)对人神经母细胞瘤细胞SH-SY5Y细胞的缺氧复氧的保护作用.方法:将体外培养的SH-SY5Y细胞分别缺氧6、12、24 h和48 h,均复氧4h后观察细胞形态改变,采用MTT法检测细胞生存率,评估细胞损伤程度.在此基础上,于缺氧12h期间首先...     

孕酮减轻ATP诱导的SH-SY5Y细胞损伤

目的:探讨孕酮对抗腺苷三磷酸(ATP)诱导的人神经母细胞瘤SH-SY5Y细胞损伤的神经保护作用和机制。方法:取对数生长期的SH-SY5Y细胞按照孕酮或ATP浓度的不同进行分组,CCK-8法检测细胞存活率,YO-PRO-1染色检测细胞膜通透性,Fluo-3染色检测细胞内Ca~(2+)浓度的变化,Western blot法检测嘌呤能P2X_7受体表达的变化。结果:与对照组相比,不同浓度(1、3、5和7 mmol/L)ATP作用2 h,SH-SY5Y细胞存活率显著降低(P0.05),细胞摄入YO-PRO-1的荧光强度明显增加(P0.05),且呈剂量依赖性。浓度为3、10和30 nmol/L的孕酮预孵育30 min可减轻ATP损伤作用,细胞存活率较单纯ATP组明显升高(P0.05或P0.01)。孕酮(30nmol/L)或P2X_7受体拮抗剂KN-62(500 nmol/L)预孵育30 min均可显著抑制ATP诱导的胞内YO-PRO-1的荧光增强(P0.01),而孕酮和KN-62两者之间没有明显差异。正常组细胞内钙离子含量少,ATP组细胞内钙离子荧光强度较对照组明显增高(P0.05),孕酮(30 nmol/L)或KN-62(500 nmol/L)预孵育30 min可明显降低(P0.05)ATP诱导的胞内钙荧光增强,而孕酮和KN-62两者之间的作用无明显差异。ATP组SH-SY5Y细胞P2X_7受体表达较对照组明显增加(P0.05),而孕酮(30 nmol/L)预孵育30 min则可显著降低ATP诱导的P2X_7受体表达(P0.05)。结论:孕酮可抑制ATP诱导的P2X_7受体表达、膜孔形成和胞内Ca~(2+)升高,降低细胞死亡率,明显减轻高浓度ATP对SH-SY5Y细胞的损伤作用。     

Dexamethasone inhibits apoptosis of human neutrophils induced by reactive oxygen species

Neutrophils are completely differentiated cells that die in tissues a few days after they migrate from the vascular compartment as a consequence of a rigouous apoptotic program. Many of the mediators produced during an inflammatory response delay neutrophil apoptosis allowing a more efficient removal of microorganisms but also favoring the tissue damage by reactive oxygen species (ROS) and lysosomal proteins released by neutrophils. Glucocorticoids delay the apoptosis of neutrophils but the mechanisms are not completely understood. To investigate the inhibition of glucocorticoids on neutrophil apoptosis we have used the glucose/glucose oxidase (G/GO) system as a constant source of hydrogen peroxide. When neutrophils are incubated in the presence of the G/GO system, a significant acceleration of their apoptotic response is observed. Preincubation with 10^–6 M, 10^–7 M, 10^–8 M or 10^–9 M of dexamethasone, negatively modulated the spontaneous and G/GO induced apoptosis of neutrophils. Then the G/GO system is a useful model to simulate the oxidative stress of neutrophils, and that the effect of DXM on neutrophil apoptosis depends, at least in part, on blocking the proapoptotic effect of ROS.     

Reactive oxygen species production and MAPK activation are implicated in tetrahydrobiopterin-induced SH-SY5Y cell death

Tetrahydrobiopterin (BH4), an obligatory cofactor for dopamine (DA) synthesis, has been shown to produce reactive oxygen species (ROS) upon its autoxidation and induce selective dopaminergic cell death in many in vivo and in vitro models of Parkinson's disease (PD). The precise molecular mechanisms underlying neuronal death upon BH4 exposure, however, have not yet been well elucidated. The present study aims to examine the intracellular ROS production and the signal transduction pathways underlying the toxic effects of BH4 on human dopaminergic SH-SY5Y cells. The results show that BH4 treatment at concentrations ranging from 50 μM to 400 μM induces neuronal death in a dose-dependent manner. In concomitant with the elevation of intracellular ROS formation, BH4-induced activation of MAPK, p38 and ERK1/2 in SH-SY5Y cells is attenuated by pretreatment with MAPK inhibitors, SB203580 or PD98059. These data indicate that MAPK activation and oxidative stress are involved in BH4-induced dopaminergic cell death, possibly through the autoxidation of BH4 and subsequent ROS production.     

雷帕霉素减轻氧糖剥夺对SH-SY5Y细胞的损伤

目的:观察雷帕霉素(Rapa)对氧糖剥夺(OGD)的人神经母细胞瘤SH-SY5Y细胞的影响,并探讨自噬在其中的作用。方法:SH-SY5Y细胞随机分为4组:正常对照组(常规培养,不进行OGD处理)、Rapa组、OGD组(无糖培养基、1%O_2的三气培养箱内孵育细胞12 h)和Rapa+OGD组。进行形态学观察;MTT法检测细胞活力;乳酸脱氢酶(LDH)漏出率判断细胞损伤的程度;caspase-3活性检测试剂盒检测酶活性;原位末端标记(TUNEL)法检测凋亡水平;Western blot法检测凋亡相关蛋白Bax和Bcl-2、自噬标志蛋白LC3B-Ⅱ及自噬调控蛋白beclin-1的表达。结果:与OGD组相比,Rapa+OGD组的细胞存活率明显升高(P0.05),LDH漏出率及caspase-3酶活性明显降低(P0.05)。TUNEL染色观察结果显示,与OGD组相比,Rapa+OGD组的细胞凋亡明显减少(P0.05);Western blot实验结果显示Rapa+OGD组的Bcl-2、beclin-1及LC3B-Ⅱ蛋白的表达水平显著高于OGD组(P0.05),而Bax蛋白水平明显低于OGD组(P0.05)。结论:Rapa对OGD损伤的SH-SY5Y细胞具有保护作用,其机制可能与上调beclin-1蛋白、激活自噬有关。     

Enhancement of reactive oxygen species and induction of apoptosis in streptozotocin-induced diabetic rats under hyperbaric oxygen exposure

An important source of reactive oxygen species (ROS) production is nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, which on activation induces superoxide production via oxidation in the mitochondria, inflammation and stress; such ROS are implicated in the pathogenesis of diabetic complications, including neuropathy. Hyperbaric oxygen (HBO) treatments are applied various diseases including diabetic patients with unhealing foot ulcers, however, and also increases the formation of ROS. In a previous study, we showed that a clinically recommended HBO treatment significantly enhanced oxidative stress of pancreatic tissue in the diabetic rats. However, no study has been undertaken with regard to the effects of HBO on the activity and gene expression of the NADPH oxidase complex and on apoptosis in the pancreas of diabetic animals. The purpose of this study was to investigate the effect of HBO exposure on gene expression of the NADPH complex, and pancreatic expression of genes related to apoptosis via the mitochondria, using the NADPH oxidase inhibitor apocynin. The mRNA expression of genes related to NADPH oxidase complex and apoptosis increased significantly (P < 0.05) in the pancreas of diabetic rats under HBO exposure. Similarly, activities of NADPH oxidase and caspase-3 changed in parallel with mRNA levels. These results suggest that oxidative stress caused by HBO exposure in diabetic animals induces further ROS production and apoptosis, potentially through the up-regulation of NADPH oxidase complex. Thus, this study can contribute to development of a better understanding of the molecular mechanisms of apoptosis via the mitochondria in diabetes, under HBO exposure.     

JNK potentiates TNF-stimulated necrosis by increasing the production of cytotoxic reactive oxygen species

The c-Jun NH(2)-terminal kinase (JNK) has been implicated in both cell death and survival responses to different stimuli. Here we reexamine the function of JNK in tumor necrosis factor (TNF)-stimulated cell death using fibroblasts isolated from wild-type, Mkk4(-/-) Mkk7(-/-), and Jnk1(-/-) Jnk2(-/-) mice. We demonstrate that JNK can act to suppress TNF-stimulated apoptosis. However, we find that JNK can also potentiate TNF-stimulated necrosis by increasing the production of reactive oxygen species (ROS). Together, these data indicate that JNK can shift the balance of TNF-stimulated cell death from apoptosis to necrosis. Increased necrosis may represent a contributing factor in stress-induced inflammatory responses mediated by JNK.     

Erythrocytes restrict microvesicle‐induced production of reactive oxygen species by polymorphonuclear leukocytes

Microvesicles (MVs) are extracellular vesicles released by several cell types upon activation or apoptosis. MVs have the potential to activate complement, which has been suggested to mediate their clearance. However, it is not clear how complement‐opsonized MVs are prevented from activating circulating polymorphonuclear leukocytes (PMNs) with release of reactive oxygen species (ROS) and potential damage of endothelium and other bystander cells as consequence. We hypothesized that binding of opsonized MVs to erythrocytes (Es) attenuates MV‐induced PMN activation. To test this, normal PMNs were exposed to MVs in the presence and absence of Es from allogenic healthy donors. As analyzed by flow cytometry, the presence of Es restricted the PMN binding of MVs by about 85% (p = 0.002) and mediated a 60–70% inhibition of the PMN production of the ROS H₂O₂, induced by MVs, when lipopolysaccharide was used as a primer (p = 0.002). The competitive binding of MVs to Es was partly dependent on complement, since EDTA inhibited MV binding to Es by 75%. These data suggest that Es, through competitive binding, may restrict MV‐induced activation of circulating PMNs and thereby serve a role as a regulator of PMN activation.     

Generation of reactive oxygen species by mitochondria in senescence-accelerated OXYS rats

Chemiluminescence assay showed that oxygen reduction and production of superoxide anion and hydrogen peroxide by liver mitochondria in OXYS rats highly sensitive to oxidative stress were less intensive than in Wistar rats. Experiments with cytochrome c oxidase inhibitors showed that decreased O₂ ^- generation in mitochondria of OXYS rats is probably associated with changes in complex III of the electron transport chain.     

As2O3诱导肿瘤细胞凋亡依赖H2O2途径

目的：探讨三氧化二砷（arsenic trioxide，As₂O₃）对人乳头瘤病毒（HPV）阳性宫颈癌HeLa细胞和HPV阴性胰腺癌AsPC-1细胞的 凋亡诱导作用与细胞内H₂O₂水平的关系。方法：采用不同浓度的As 2O3处理HeLa细胞和AsPC-1细胞不同时段，显微镜下观察细胞的凋亡，噻唑蓝（MTT）法 测定细胞生长抑制情况；不同浓度的As₂O₃处理细胞2、5、8、12、24 h后，用DCFH-DA 标记检测细胞内的H₂O₂水平。结果：2 μmol/L As₂O₃处理HeLa 细胞48 h后细胞的生长受到明显抑制，表现出细胞凋亡的特征，随着As₂O₃浓度的增加 和作用时间的延长效果更加明显。而 1 μmol/L As₂O₃处理AsPC-1细胞24 h 即呈 现明显 的生长抑制和凋亡特征。As₂O₃处理HeLa细胞2 h细胞内H₂O₂的水平比对照组升高(1 0 μmol/L组达51.30%)，持续到8 h达到高峰（升高84.19%），12 h后下降，24 h水平与 对照组接近，并有明显的剂量依赖性。As₂O₃处理AsPC-1细胞2 h后，细胞内H₂O₂的 水平也明显升高（10 μmol/L组达79%），持续到5 h达到高峰（增高169%），且该细胞内H₂O₂水平升高比HeLa细胞更明显，12 h之后的变化情况与HeLa细胞类似。结论:As₂O₃诱导HeLa细胞和AsPC-1细胞凋亡与细胞内的H₂O₂水平改变有关,而与HPV的感染无明显相关性。H₂O₂积累是As₂O₃诱导细胞凋亡途径中的早期事件,H₂O₂可能在As₂O₃诱导肿瘤细胞凋亡途径中扮演类似第二信使的作用。