鱼藤酮诱导PC12细胞自噬的初步研究

目的 研究鱼藤酮处理对PC12细胞自噬水平的影响.方法 培养PC12细胞,分别用0、0.01、0.05、0.1、0.5、1、5、10tmol/L鱼藤酮处理细胞12 h,以及1μmol/L鱼藤酮分别处理细胞0、2、6、12、18、24 h,Western blot检测各组细胞内LC3-Ⅰ和LC3-Ⅱ含量,荧光显微镜检测GFP-LC3荧光斑点的数量,透射电镜观察细胞超微结构.结果 随着鱼藤酮处理浓度升高,LC3-Ⅱ/LC3-Ⅰ比值和GFP-LC3荧光斑点数量均随之增加;随着鱼藤酮处理时间延长,GFP-IC3荧光斑点数量也随之增加,LC3-Ⅱ/LC3-Ⅰ比值先升高后降低,透射电镜显示细胞线粒体受损和细胞自噬水平增加.结论 鱼藤酮对PC12细胞自噬的影响具有量效性和时效性.     

6-羟基多巴胺致PC12细胞损伤机制中自噬的影响

目的 研究自噬在帕金森病(PD)细胞模型中的作用及可能的机制.方法 体外培养的PC12细胞加入6-羟基多巴(6-OHDA)诱导多巴胺能神经元损伤模型.利用透射电镜观察PC12细胞中自噬的激活,免疫印迹法检测LC3-Ⅱ、Cathepsin B蛋白的表达.结果 电镜下观察到6-OHDA可使PC12细胞内自噬体增多,并出现了凋亡特征.6-OHDA作用2h(灰度比:52.57±2.27),4h(灰度比:56.83±3.51),6h(灰度比:73.43±5.41),12h(灰度比:103.90±2.57),24h(灰度比:100.40±3.91)时LC3-Ⅱ表达逐渐升高,与正常对照组(42.10±2.05)比较差异有统计学意义(P＜0.05),模型组Cathepsin B(113.80±4.46)表达与正常对照组(35.89±3.40)比较明显增加(P＜0.01),与模型组相比,广谱蛋白酶抑制剂UTI组(57.69±4.24)降低Cathepsin B表达(P＜0.01).结论 自噬/溶酶体途径参与PC12细胞的死亡过程:6-OHDA诱导自噬过度激活,LC3-Ⅱ与Cathepsin B表达增加,促进细胞死亡.

Abstract：

Objective To investigated the role of the autophagy lysosomal pathway in PD cells and the possible molecular mechanisms. Methods A dopaminergic neuronal injury model was induced by 6-OHDA in PC12 cells . Autophagosomes in PC12 cells were examined by transmission electronmicro-scopy( TEM ). The expression of LC3- Ⅱ , Cathepsin B were assayed by western blot analysis. Results TEM revealed that the autophagosomes were increased in PC12 cells after 6-OHDA treatment and appeared apoptosis. The LC3-Ⅱ (2h:52.57 ±2.27,4h:56.83 ±3.51,6h:73.43 ±5.41,12h:103.90 ±2.57,24h: 100.40 ±3.91 )and Cathepsin B expression ( model group: 113.80 ± 4.46; normal group 35.89 ± 3.40) were increased after 6-OH DA treatments (P ＜ 0.05 or P ＜ 0.01 ). Conclusion The results indicate that autophagy lysosome pathway is involved in 6-OHDA-induced cell death in PC12 cells.     

罗哌卡因对HeLa细胞自噬及自噬溶酶体的影响

目的:探究罗哌卡因对HeLa细胞自噬及自噬溶酶体的影响方法:采用HeLa、HeLa-GFP-LC3、HeLa-RFP-LAMP1等细胞系进行研究,并将细胞分为空白对照组、饥饿组(饥饿处理0、4、12 h)和罗哌卡因组(10 mg/mL罗哌卡因,处理0、4、12 h),使用显微成像技术联合多种生化手段检测罗哌卡因处理的细胞中自噬的诱导、自噬溶酶体形态及溶酶体数目.结果:罗哌卡因组与空白对照组细胞相比产生大量LC3点状聚集,并且LC3Ⅱ蛋白水平明显提高(P<0.05);相比于空白对照组细胞,罗哌卡因组和饥饿组细胞经4h处理后产生大量自噬溶酶体,罗哌卡因组细胞自噬溶酶体体积大于饥饿处理组;饥饿组细胞溶酶体数目在4 h减少,而在12 h有所恢复,但是罗哌卡因组细胞溶酶体数目持续减少无法恢复.结论:罗哌卡因可引发HeLa细胞自噬并破坏自噬溶酶体.     

细胞自噬与肿瘤发生关系研究进展

细胞自噬可通过溶酶体吞噬降解自身结构,分为大自噬、小自噬和分子伴侣介导自噬,具有广泛的生物学作用。细胞自噬在肿瘤的发生、发展过程中起双重调节作用,既可对肿瘤细胞产生抑制作用,又可促进其发生和发展,肿瘤细胞可释放特定的信号分子来诱导间质细胞自噬,而此过程中所产生的营养物质又为肿瘤细胞的生长、繁殖和转移提供了必要的基础和条件。     

针灸调控自噬溶酶体通路治疗神经系统等疾病的机制研究进展

作为中国传统医学的重要组成部分,针灸的疗效与现代科学内涵越来越受到人们的关注。近年来严格的随机对照临床试验证实了针灸对某些优势病种的疗效,基础研究初步揭示了针灸治病的作用机理。本文通过分析过往文献,结合本团队的相关研究工作,综述了针灸治疗神经系统等疾病的自噬溶酶体通路（ALP）调控机制的研究进展。我们发现,在不同疾病模型中,针灸通过上调或者下调ALP改善相关病理,且穴位分布与ALP的单向/双向调节存在一定相关性;但是目前的研究在实验设计和方法学方面存在一定的缺陷,针灸调控ALP的分子机制有待进一步阐明。     

溶酶体膜蛋白sidt2介导肝脏细胞的凋亡：不通过抑制自噬溶酶体途径

目的 研究溶酶体膜蛋白Sidt2敲除后在肝脏细胞中调控凋亡的途径。方法 利用Crispr-Cas9技术构建Sidt2敲除的人肝脏(HL7702)细胞模型,检测Sidt2和自噬关键蛋白LC3-/、P62蛋白水平,MDC染色观察自噬体形成情况,通过EdU和流式细胞实验观察Sidt2对肝脏细胞增殖活性和凋亡的影响,并且使用0、10、25、50、100、200μmol/L的氯喹(CQ)摸索肝脏细胞CQ饱和浓度,检测对其自噬流的影响,以及使用CQ进一步探索影响肝脏细胞的增殖活性其凋亡水平的机制。结果 成功构建HL7702细胞Sidt2^+/+组及Sidt2^-/-组。Sidt2基因缺失可导致肝脏细胞增殖被抑制和凋亡水平的增加,自噬关键蛋白LC3-/和P62在蛋白水平上的表达均增加且自噬体含量增加(P<0.05)。结果显示50μmol/L CQ作用下肝脏细胞自噬达到饱和状态,50μmol/L CQ使Sidt2基因缺失时LC3B和P62的表达均增加(P<0.05),且CQ进一步降低肝脏细胞活性,并促进其凋亡水平(P<0.05)。结论在离体水平...     

自噬-溶酶体途径与骨骼肌和膈肌萎缩的研究进展

 骨骼肌是人体重要的运动器官和能量代谢靶器官。呼吸肌是特殊的骨骼肌,因为它们在生命过程中持续运动。膈肌是最主要的吸气肌,相较外周骨骼肌,其血供更为丰富,抗疲劳能力和氧化代谢能力更强。多种疾病状态下均可出现骨骼肌和膈肌萎缩及功能异常。肌萎缩的主要机制为蛋白分解增加而蛋白合成下降,而病理状态下肌萎缩主要由肌肉蛋白分解增加造成。自噬-溶酶体(autophagy-lysosome,AL)途径在维持骨骼肌质量动态平衡中起重要作用,其主要功能是将细胞质中多余或损伤的蛋白和细胞器运输至溶酶体进行降解。适当活性的AL途径能通过清除细胞代谢产物来保持内稳态,在维持骨骼肌质量中起保护作用;而过度激活的AL途径能使蛋白分解状态加重,导致肌萎缩。本文就AL途径在骨骼肌和膈肌萎缩中所起的作用及其机制作一综述。     

人参二醇对鱼藤酮、MPP+诱导的PC12细胞损伤的作用

目的观察人参二醇对鱼藤酮、MPP+诱导的大鼠嗜铬细胞瘤损伤的影响。方法以大鼠嗜铬细胞瘤PC12细胞为研究对象,以鱼藤酮（0.3、1、3、10、30μmol/L）或MPP+（0.1、0.3、1、3mmol/L）诱导细胞损伤。设阴性对照组、人参二醇对照组（10、25、50、75、100mg/L）、鱼藤酮（3μmol/L,24h）或MPP+（1mmol/L,48h）组,人参二醇（10、25、50、75、100mg/L）联合鱼藤酮（3滋mol/L）或MPP+（1mmol/L）组。采用MTT法检测细胞增殖活性;PI和Hoechst 33342染色检测细胞坏死和凋亡;并以免疫组织化学测定细胞酪氨酸羟化酶（TH）的表达。结果人参二醇（10、25、50、75、100mg/L）本身不会抑制PC12细胞增殖,其中50、75mg/L人参二醇还可促进细胞增殖;各浓度人参二醇对鱼藤酮诱导的细胞损伤均不具有保护作用;在MPP+处理诱导细胞损伤后,50、75mg/L人参二醇可提高细胞增殖活性,但人参二醇对细胞凋亡和坏死及TH的表达无影响。结论人参二醇（50、75mg/L）对MPP+诱导的PC12细胞损伤有保护作用,其作用机制与促进细胞增殖有关;人参二醇对鱼藤酮诱导的细胞损伤无明显保护作用。     

葛根素对过氧化氢诱导PC12细胞损伤的保护作用

目的:研究葛根素对过氧化氢(H2O2)诱导PC12细胞损伤的影响。方法:建立H2O2致PC12细胞损伤模型,倒置相差显微镜下进行一般形态学观察,化学比色法测定乳酸脱氢酶(LDH)释放量及细胞培养液和细胞内丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性。结果:100μmol/L H2O2诱导PC12细胞4 h,细胞呈现明显损伤形态,LDH释放量升高(P<0.001),细胞培养液和细胞内MDA含量增加(P<0.001),SOD活性下降(P<0.001)。葛根素可明显改善形态学损伤,显著降低LDH释放量和细胞培养液及细胞内MDA含量,提高SOD活性。结论:葛根素对H2O2诱导PC12细胞损伤具有保护作用,其作用机制可能与提高PC12细胞的抗氧化能力有关。     

Mechanisms of MPP+-induced PC12 cell apoptosis via reactive oxygen species

Apoptosis of dopaminergic neurons in the nigrostriatal projection plays a crucial role in the pathogenesis of Parkinson’s disease (PD). Although the detailed mechanisms responsible for dopaminergic neuron loss are still under investigation, oxidative stress is identified as a major contributor for neuronal apoptosis. In the current study, we studied the effects of MPP+, a substrate that mimics oxidative stress, on neuron-like PC12 cells and the underlying mechanisms. PC12 cells were cultured and treated by 100 μmol/L MPP+ for 4, 8, 16, 24 and 48 h, respectively. For drug pretreatment, the PC12 cells were incubated with N-acetyl-l-cysteine (NAC, 5 mmol/L), an antioxidant, SP600125 (20 μmol/L) or PD98059 (100 μmol/L), two pharmacological inhibitors of JNK and ERK1/2, for 1 h before addition of MPP+. Cell apoptosis was measured by flow cytometry. The mRNA expression of Cu2+/Zn2+-SOD, GSH-Px, Bcl-2 and Bax was detected by RT-PCR. The protein expression of p-ERK1/2 and p-JNK was determined by Western blotting. Our results showed that MPP+ exposure could induce substantial PC12 cell apoptosis. The pretreatment of SP600125 or PD98059 could effectively reduce the apoptosis rate by reducing the ratio of Bax/Bcl-2 mRNA levels. MPP+ exposure also induced high level of reactive oxy-gen species (ROS), marked by dramatic increase of Cu2+/Zn2+-SOD and GSH-Px mRNA levels. The elevated ROS was strongly associated with the activation of JNK and ERK1/2 signal pathways after MPP+ exposure, since the pretreatment of NAC significantly reduced the upregulation of p-JNK and p-ERK1/2. Finally, the pretreatment of SP600125, but not PD98059, alleviated the increase of Cu2+/Zn2+-SOD and GSH-Px mRNAs induced by MPP+, suggesting that the activation of the JNK signal pathway, but not the ERK1/2 signal pathway, could, in some degree, antagonize the generation of ROS induced by oxidative stress. In conclusion, our results suggest that JNK and ERK1/2 signal pathways, which are activated via ROS, play a crucial role in neuronal apoptosis ind     

EGb对MPP^＋诱导的PC12细胞凋亡的影响

目的 观察EGb对MPP^ 诱导的PC12细胞凋亡的细胞。方法 MPP^ 诱导PC12细胞凋亡,AO／EB染色,荧光显微镜下观察凋亡细胞。结果 EGb50、100μg/ml在6h、12h、24h可抑制细胞凋亡,而EGb25μg/ml则无效。结论 EGb在6h、12h、24h时呈剂量依赖性降低细胞凋亡率,提示EGb有可能通过抑制DA能神经元凋亡而相对增加DA含量。     

红景天苷通过抑制NOX2-ROS-MAPKs信号途径保护H2O2诱导的PC12细胞凋亡

目的 探讨红景天苷保护H2O2诱导PC12细胞凋亡的分子机制.方法 PC12细胞置于含10％马血清、5％胎牛血清的高糖DMEM完全培养基中常规培养.不同浓度的红景天苷预处理细胞2h,然后H2O2作用细胞特定的时间,Western blot检测细胞凋亡相关蛋白PARP,caspase 3的表达及胞内信号分子p38,ERK和JNK的磷酸化水平;DAPI染色检测细胞核的形态改变;ROS检测试剂盒检测胞内ROS的水平;膜质分离实验检测NOX2的两个重要亚基gp91phox和p47phox在胞膜和胞质中的含量;免疫共沉淀实验检测gp91phox和p47phox的结合.结果 红景天苷浓度依赖性的抑制H2O2诱PC12细胞凋亡;减弱H2O2诱导p38,JNK和ERK的磷酸化;减少H2O2诱发的ROS释放;抑制gp91phox和p47phox的结合,进而抑制NOX2的活性.结论 红景天苷通过抑制NOX2-ROS-MAPKs信号通路保护H2O2诱导PC12细胞凋亡.     

葛根多糖对PC12细胞增殖的损伤作用

目的 :探讨葛根多糖 (totalpolysaccharideofPueraria ,TPP)对嗜铬细胞瘤细胞PC 12增殖的影响。方法 :用细胞培养的方法检测TPP单独或与H2 O2 一起对PC 12细胞活力的影响 ;MTT法检测细胞活力 ,Griess试剂测定细胞外液中的亚硝酸盐含量 ;次黄嘌呤黄嘌呤氧化酶化学发光体系测定细胞外液中的SOD活性。结果 :0 .0 1～ 1.0mg·ml 1的多糖明显地抑制细胞生长 ,并可增强H2 O2 导致的细胞损伤 (P <0 .0 5 ) ;细胞外液中的SOD活性随多糖的浓度增加而降低 ;其亚硝酸盐产物增多 ,并呈浓度依赖性。结论 :TPP对嗜铬细胞瘤细胞PC 12的增殖具有损伤作用。     

Propofol may protect PC12 cells from induced apoptosis through the signaling pathway

Background There are two major pathological hallmarks of AIzheimer's disease.One is the progressive accumulation of beta-amyloid (Aβ) in the form of senile plaques; the other is hyperphosphorylated tau,causing neuronal apoptosis.Some inhalation anesthetics,such as isoflurane and desflurane,have been suggested to induce Aβ accumulation and cause AD-like neuropathogenesis.Whether intravenous anesthetics have similar effects is still unclear.We therefore set out to determine the relationship between propofol and AD-like pathogenesis.Methods PC12 cells were cultured in serum-free medium for 12 hours prior to drug treatment.Various concentrations from 5 μmol/L to 80 μmol/L of aggregated Aβ25-35 were added to determine a proper concentration for further study.After exposure to 10 μmol/L Aβ25-35 alone or with 20 μmol/L propofol for 6 hours,PC12 cell viability was determined by MTT assay.Western blotting and immunocytochemical staining were performed to observe the protein expression of the Bcl-2 family,tau phosphorylation at different sites,and tau protein kinases and phosphatases.Results Aβ25-35 induced a decrease in PC12 cell viability in a dose-dependent manner.Exposure to 10 μmol/L Aβ25-35 for 6 hours resulted in the mild cell survival,accompanied by a decline in Bcl-2,and an increase in phosphorylation of GSK-3β and tau at different sites.Compared with the Aβ25-35 group,cells treated with propofol alone showed no significant difference,while cells co-incubated with propofol and Aβ25-35 showed a significantly higher survival rate (P ＜0.01 or P ＜0.05).Tau phosphorylation at Ser396,Ser404 and Thr231 and the level of GSK-3β in PC12 cells increased after exposure to 10 μmol/L Aβ25-35.Co-incubation with propofol attenuated cellular apoptosis by inhibiting tau phosphorylation.Conclusions These data indicate that propofol may protect PC12 cells from Aβ25-35-induced apoptosis and tau hyperphosphorylation through the GSK-3β pathway,therefore it may be a safer anesthesia for AD and elderly patients.     

MPP+对PC12细胞体外生长增殖的毒性作用

目的: 研究不同剂量1-甲基-4苯基-吡啶离子(MPP )对大鼠嗜铬细胞瘤PC12细胞生长增殖的抑制作用,探讨MPP 多巴胺能神经毒性机制. 方法: PC12细胞体外培养,以100～700 μmol/L MPP 进行染毒. MTT法测算MPP 作用1～7 d对PC12细胞的抑制情况并绘制生长曲线;取4 d为作用时间,细胞计数法观察MPP 对细胞的抑制率;透射电镜观察细胞形态学变化,流式细胞仪检测细胞凋亡率及细胞周期改变情况. 结果: 细胞生长曲线的改变证实MPP 对PC12细胞的生长增殖有显著抑制作用,而且呈时间-剂量-效应关系. 细胞生长抑制试验结果显示100～700 μmol/L MPP 对细胞的抑制率为0.22～0.66 (P<0.01);透射电镜观察发现MPP 可诱导PC12细胞发生凋亡的形态学改变,同时伴有线粒体肿胀;流式细胞仪检测显示100, 300 μmol/L MPP 作用后,细胞总凋亡率比对照组分别增加0.51和0.62 (P<0.01). 结论: MPP 对PC12细胞的生长增殖有明显的抑制作用,而诱导细胞凋亡可能是MPP 产生多巴胺能神经毒性的重要机制之一.     

灵孢多糖对MPP+损伤PC12细胞的保护作用

[目的]观察灵孢多糖(GLPS)对甲基-苯基-吡啶离子(MPP+)诱导损伤的PC12细胞的保护作用.[方法]将MPP+或GLPS加入体外培养的PC12细胞中,建立多巴胺能神经元损伤模型,用四甲基偶氮唑盐(MTT)检测细胞活力的变化;以乳酸脱氢酶(LDH)检测法检测培养上清液中LDH水平的改变;通过酪氨酸羟化酶(TH)免疫细胞化学法检测TH阳性细胞数及蛋白的表达.[结果]MPP+处理48 h后,细胞活力降至对照组的52%,经GLPS(100、200、300 μg/mL)预处理后,细胞活力明显提高,分别为65%,75%,79%(P＜0.05).MPP+处理48 h后,上清液中LDH水平较对照组明显提高,经不同浓度的GLPS预处理后,上清中LDH水平有所下降(P＜0.05),且TH阳性细胞数及表达强度明显高于MPP+组.[结论]灵孢多糖对MPP+诱导损伤的PC12细胞具有保护作用.     

Minocycline protects the apoptosis of PC12 cells induced by 1-methyl-4-phenylpyridinium

Objective： To explore the protective effect of minocycline on the apoptosis of cellular parkinsonism models induced by MPP^＋ . Methods： Using PC12 cells as the apoptotic model of dopaminergic neurons, MC and MPP^＋ were added into the culture medium of PC12 cells, and using MTr to assay the cell viability and metabolic state; The cells apoptosis was assayed by electrophoresis method and using flow cytometry FACS to assay the apoptosis ratio. Results： Added the MPP^＋ to get the concentration of 10μmol/L, the cellular parkinsonism model of apoptosis had been prepared. The pre-treatment of MC （ 100/μmol/L） could significantly increase the PC12 cell viability. The apoptosis ratio of MC＋MPP^＋ group was significantly lower than that of MPP^＋ group, but was still significantly higher than that of control group. Conclusion： MC may protect the cell apoptosis induced by MPP^＋ to some extent.     

Geniposide inhibits CoCl2-induced PC12 cells death via the mitochondrial pathway

Background A number of studies have shown that oxidative stress and mitochondrial involvement are major triggering factors in the development of neurodegenerative diseases. Cobalt chloride （CoCl2）-induced cell death in PC12 cells may serve a simple and convenient in vitro model of hypoxia-induced neuronal cytotoxicity. To explore the effect of geniposide on COCl2 which induced cytotoxicity and mitochondrial function in rat pheochromocytoma PC12 cells, we analyzed the influence of geniposide on the expression of apoptosis-related proteins. Methods PC12 cells and RNAi PC12 cells were treated with 0, 12.5, 25, 50, 100 umol/L geniposide for 12 hours and then exposure to 400 umol/L COCI2 for 12 hours. Cell viability, cell morphology, and expression of Bcl-2, Bax, P53 and caspase-9 were determined using Western blotting. Results Pretreatment with geniposide markedly improved the cells viability and morphology, decreased the expression of Bax, P53 and caspase-9, and increased the expression of Bcl-2 in PC12 cells challenged by CoCl2. However, in the RNAi PC12 cells, geniposide had no significant effect on the expression of these proteins. Conclusion Geniposide protects PC12 cells from CoOl2 involved in mitochondrial mediated apoptosis, and GLP-1R might play a critical role in the neuroprotection of geniposide in PC12 cells.