天麻素对乙醇诱导肝细胞株L02细胞损伤的影响

目的:探讨天麻素对乙醇诱导肝细胞株L02损伤的影响。方法:将人肝细胞株L02培养,加入不同浓度的乙醇,采用MTT比色法确定乙醇作用的浓度。用流式细胞仪测定细胞活性氧簇(ROS)及线粒体膜电位的改变;采用反相高效液相色谱(RP-HPLC)分析法检测细胞ATP含量。结果:乙醇(25 mL/L)作用36 h可损伤肝细胞,细胞内ROS的水平明显增加;而细胞线粒体膜电位及肝细胞中ATP的含量则显著降低(P0.01)。天麻素具有减轻细胞损伤的作用,并可降低损伤的肝细胞内ROS的含量,增加细胞线粒体膜电位和ATP的水平。结论:天麻素可抑制乙醇诱导的肝细胞损伤及脂质过氧化反应,改善线粒体功能,增加能量合成,发挥保护肝细胞的作用。     

瘦素对缺氧复氧L02肝细胞凋亡及Fas/FasL表达的影响

目的： 观察瘦素(leptin)对缺氧复氧人正常肝细胞（L02）凋亡的影响。方法: 将L02细胞分别分为正常对照组、单纯缺氧12 h复氧组(IR组)和缺氧12 h复氧加不同浓度的瘦素（分别为100 μg/L、200 μg/L、400 μg/L、800 μg/L 和1 600 μg/L）干预组, 以流式细胞仪分析、DNA缺口末端标记 (TUNEL) 试验、荧光定量 PCR 等方法观察leptin 对L02肝细胞凋亡、Fas/FasL mRNA表达的影响。结果: （1）与正常对照组相比,IR组细胞凋亡率和TUNEL细胞阳性率增加（P<0.01）,加用不同浓度瘦素干预组的细胞凋亡率和TUNEL细胞阳性率与IR组相比明显下降（P<0.05）;（2）与正常对照组相比,IR组 L02 细胞中Fas/FasL mRNA表达明显上调(P<0.01);加用不同浓度瘦素干预组与IR组相比,Fas/FasL mRNA表达下降,以400 μg/L瘦素作用明显,结果有显著差异（P<0.05）。结论: 瘦素能减轻缺氧复氧培养L02肝细胞的凋亡,其机制可能与其下调细胞中Fas/FasL mRNA的表达有关。     

三七总皂甙对脂肪变性L02肝细胞TG含量及LXRα mRNA表达的影响

目的： 观察三七总皂甙(PNS)对脂肪变性L02肝细胞内甘油三酯(TG)含量及肝X受体α（LXRα）mRNA表达的影响,探讨其对脂肪变性肝细胞的降脂作用及机制。方法: 采用50%小牛血清诱导L02肝细胞48 h建立肝细胞脂肪变性模型,采用MTT法测定PNS作用于脂肪变性肝细胞的适宜浓度,随后将其分为5组,模型组、自然恢复组、PNS低剂量组（10 mg·L-1）、PNS高剂量组（50 mg·L-1）,并设正常组,除模型组继续予含50%小牛血清的 RPMI-1640培养基培养外,余组均改予含10%小牛血清培养。药物作用24 h后,油红O染色观察肝细胞内脂滴变化,全自动生化仪检测肝细胞内TG含量,运用RT-PCR法检测肝细胞内LXRα mRNA的表达。结果: 与正常组比较,油红O染色示模型组肝细胞内橘红色脂滴明显增加,并出现脂滴融合现象,模型组TG含量明显升高（P＜0.01）。PNS治疗24 h后,PNS各治疗组与自然恢复组比较,肝细胞内TG含量均明显减少（P＜0.05）,以低剂量组下降更为显著（P＜0.01）;油红O染色显示,PNS低剂量组肝细胞内脂滴数减少最为明显。与正常组比较,模型组肝细胞LXRα mRNA的表达明显上调（P＜0.01）;与自然恢复组比较,PNS各治疗组肝细胞LXRα mRNA的表达量均有下降,以低剂量组下降显著（P＜0.05）。结论: PNS能显著降低脂肪变性肝细胞内TG含量,减轻肝细胞脂肪变性。LXRα mRNA的高表达与肝细胞脂肪蓄积密切相关,PNS可能是通过下调LXRα mRNA的表达来改善肝细胞的脂肪变性。     

神经生长因子通过TrkA信号途径促进肝细胞增殖

目的: 观察神经生长因子(NGF)及其受体(TrkA^NGFR和p75^NTR)在肝细胞中的表达,探讨外源性神经生长因子 β(NGF-β)对肝细胞的生物学作用。方法: 体外培养L02肝细胞,免疫细胞化学和荧光定量PCR法分别检测NGF、TrkA^NGFR和p75^NTR在L02细胞中的表达。XTT法检测外源性NGF-β、anti-NGF、anti-TrkA^NGFR和anti-p75^NTR对L02细胞增殖的作用,流式细胞术检测外源性NGF-β对L02细胞凋亡和细胞周期的影响。结果: L02细胞表达NGF及其受体TrkA^NGFR、p75^NTR,NGF主要位于细胞质和细胞核,TrkA^NGFR和p75^NTR位于细胞质和细胞 膜;外源性NGF-β上调L02细胞表达NGF和TrkA^NGFR。低剂量外源性NGF-β(12.5~200 μg/L) 通过调控L02细胞的S期,促进细胞增殖,抗细胞凋亡,高剂量(>400 μg/L)NGF-β不能促进L02细胞增殖;anti-NGF和anti-TrkA^NGFR抑制NGF-β诱导的L02细胞增殖,anti-p75^NTR并不影响NGF-β诱导的L02细胞增殖。结论: L02细胞表达NGF及其受体TrkA^NGFR、p75^NTR;合适剂量外源性NGF-β可能通过NGF/TrkA^NGFR信号途径促进L02细胞增殖。     

硫化氢对抗过氧化氢对PC12细胞的损伤作用

目的探讨硫化氢(hydrogen sulfide,H2S)对抗过氧化氢(hydrogen peroxide,H2O2)对PC12细胞的损伤作用及有关机制。方法应用H2O2在PC12细胞建立氧化应激损伤的实验模型;应用甲氮甲唑蓝(MTT)法检测细胞存活率,碘化丙啶(PI)染色流式细胞技术(FCM)检测细胞凋亡率,罗丹明123(Rhodamine 123,Rh123)染色FCM检测细胞线粒体膜电位(mitochondrial membrane potential,MMP),双氢罗丹明123染色FCM检测细胞内活性氧(reactive oxygen species,ROS)的含量。应用硫化氢钠(sodium hydrosulfide,NaHS)作为H2S的供体。结果200μmol和400μmolH2O2作用PC12细胞24h均使细胞的存活率明显降低及凋亡率显著增加,200μmolH2O2引起PC12细胞的MMP明显降低及ROS生成显著增多。当NaHS与H2O2(200或400μmol/L)共同作用于PC12细胞时,NaHS(100～400μmol/L)浓度依赖性的阻断H2O2引起PC12细胞的存活率降低及细胞凋亡率增加。400μmolNaHS明显地阻断200μmolH2O2引起PC12细胞的MMP降低及ROS增多。结论H2S能明显地保护PC12细胞对抗H2O2引起的损伤,阻断MMP降低及ROS生成可能是H2S的细胞保护机制之一。     

NADH对L02细胞Bcl-2、Bax、P53、CD95及CD95L表达的影响

目的：研究抗氧化剂NADH对体外培养的正常人肝细胞系L02缺血再灌注损伤的保护作用及可能的机制。方法：实验分组：将培养的L02细胞分为：缺血再灌注损伤组（I／R），缺血再灌注损伤＋NADH（I／R＋NADH）及对照组（未经处理的L02细胞）。用流式细胞仪观察细胞处理后6、12、18及24h细胞的凋亡率及12h时，Bcl-2、Bax、P53、CD95及CD95L的表达，并以透射电镜观察细胞凋亡的超微结构。结果：NADH可明显抑制缺血再灌注损伤细胞的凋亡，并能上调Bcl-2表达，下调Bax、P53、CD95及CD95L的表达，与I／R组相比较差异显著（P＜0．05）。透射电镜下可见典型的凋亡细胞的特征。结论：NADH对缺血再灌注损伤诱导的L02肝细胞有明显地保护作用。其作用机制可能与通过调节Bcl-2、Bax、P53、CD95及CD95L的表达有关。     

大肠杆菌脂多糖和氢化考的松诱导胸腺细胞凋亡的实验研究

用琼脂糖凝胶电泳、电镜等方法研究大肠杆菌脂多糖（ＬＰＳ）和氢化考的松所致的小鼠胸腺细胞凋亡，以建立适于实验的细胞凋亡模型，并确定了凋亡模型的最佳用药剂量和时相。实验结果表明，ＬＰＳ和氢化考的松均可诱导小鼠胸腺细胞发生凋亡，ＬＰＳ腹腔注射量为２５μｇ／只时造模较为适宜，造模最佳时相为腹腔注射１８ｈ，氢化考的松模型经测定其最佳时相为肌肉注射２４ｈ。两种凋亡模型比较，ＬＰＳ模型造模时间短（仅需１８ｈ），     

二氧化锗诱导L6成肌细胞株的MyoD基因表达

目的：探讨成肌细胞的MyoD基因在线粒体肌病发生发展中的作用。方法：采用二氧化锗(GeO2)处理大鼠的成肌细胞系L6，观察细胞形态的变化，利用MTT分析GeO2对成肌细胞的影响，用RT-PCR检测MyoD基因表达。结果：发现GeO2在损伤成肌细胞的同时，能够诱导MyoD基因的表达，表明MyoD基因在线粒体肌病的发生发展中起着重要作用。结论：MyoD基因表达的增强是线粒体肌病中骨骼肌萎缩的一个信号分子，MyoD基因表达有可能成为线粒体肌病检测的参考指标。     

小檗碱对人脐静脉内皮细胞增殖与凋亡的作用

目的：观察小檗碱对人脐静脉内皮细胞增殖与凋亡的作用，以探讨小檗碱抑制肿瘤生长与转移的机制。 方法： 用小檗碱与体外培养的人脐静脉内皮细胞（HUVEC）共同孵育，以MTT法检测细胞的增殖活性，免疫细胞化学法检测增殖细胞核抗原（PCNA）的表达，荧光染色法观察凋亡细胞核形态，用Rhodamine123染色，激光共聚焦显微镜检测线粒体膜电位。 结果： 不同浓度小檗碱与HUVEC共同孵育可明显抑制HUVEC的增殖(P<0.05，P<0.01)，呈现一定的浓度依赖性和时效性；20 mg/L小檗碱与HUVEC共同孵育48 h，可显著降低细胞核PCNA的表达（P<0.01），并可见凋亡细胞数增多、线粒体膜电位明显降低（P<0.01）。 结论： 小檗碱抑制血管内皮细胞的增殖，并促进血管内皮细胞凋亡，从而抑制肿瘤血管形成，可能是小檗碱抑制肿瘤生长与转移的机制之一。     

脂多糖结合蛋白抑制肽抑制脂多糖与人单核巨噬细胞株的结合

目的： 研究脂多糖结合蛋白（LBP）抑制肽对脂多糖（LPS）与人单核巨噬细胞株U937细胞结合的抑制作用，从而探讨LBP抑制肽阻断内毒素信号转导通路的机制。 方法: 夹心ELISA检测LBP抑制肽与LPS的相对亲和力；流式细胞检测分析（FACS）异硫氰酸荧光素标记的LPS（FITC-LPS）与U937细胞的结合；ELISA检测U937细胞培养上清液中肿瘤坏死因子α（TNF-α）的含量。 结果： 在相同的浓度下，LBP抑制肽与LPS的亲合力比LBP高，约为LBP的1.15倍。LPS组平均荧光强度（MFI）明显高于对照组，LBP显著增强了LPS与U937细胞的结合，促进了LPS的内在化；LBP抑制肽组MFI显著低于LBP组(P<0.01)，即P12减弱了FITC-LPS与U937细胞的结合。而且P12抑制了LPS诱导的U937细胞TNF-α的生成。 结论： LBP抑制肽与LPS有一定的亲和力，LBP抑制肽与LBP的致炎位点竞争结合FITC-LPS，从而抑制LPS与单核巨噬细胞的结合，阻止了LPS的内在化，并显著降低了LPS诱导的TNF-α释放。     

Ectopic Over-expression of Oncogene Pim-2 Induce Malignant Transformation of Nontumorous Human Liver Cell Line L02

In order to prove that ectopic over-expression of Pim-2 could induce malignant transformation of human liver cell line L02, three groups of cells were set up including human liver cell line L02 (L02), L02 cells transfected with Pim-2 gene (L02/Pim-2) and L02 cells transfected with empty-vector (L02/Vector). Pim-2 expression levels were detected. The morphology, proliferation level, apoptosis rate and migration ability of the cells were detected respectively. Then the cells were subcutaneously inoculated into athymic mice and the microstructures of the neoplasm were observed. Compared with the controls, Pim-2 expression levels were significantly higher in L02/Pim-2 cells (P<0.05), and their morphology had obvious malignant changes. They also showed a significantly increased proliferation rate (P<0.05) and migration capacity (P<0.05), as well as a significantly decreased apoptosis rate (P<0.05). Only the athymic mice inoculated with L02/Pim-2 cells could generate neoplasm, and the morphology of the neoplasm coincided with that of the hepatoma. The results manifest that ectopic Pim-2 gene could be stably expressed in L02/Pim-2 cells. Both the morphological and biological changes of L02/Pim-2 cells demonstrate the trend of malignant transformation. L02/Pim-2 cells could generate hepatoma in athymic mice. In conclusion, Pim-2 could induce malignant transformation of human liver cell line L02.     

雷公藤红素诱导CEM-6T细胞凋亡的机制研究

在已经证明雷公藤红素能诱导人T淋巴细胞株CEM 6T细胞凋亡的基础上 ,进一步探讨此凋亡过程的机制。本项目研究雷公藤红素诱导CEM 6T细胞凋亡过程中Fas/FasL、ICEmRNA的变化以及ICE抑制剂、磷酸酶抑制剂对凋亡的影响。结果发现 ( 1)CEM 6T细胞表达Fas,不表达FasL ,雷公藤红素处理不能改变这一情况 ;( 2 )雷公藤红素不能改变ICEmRNA的表达水平 ,但ICE抑制剂Ac YVAD CHO能使雷公藤红素诱导CEM 6T的凋亡率下降 ;( 3) 1 5 μmol/L磷酸酶抑制剂okadaicacid能使凋亡率下降。提示雷公藤红素诱导CEM 6T细胞凋亡不依赖Fas/FasL ,而与细胞内原已存在的ICE有关 ,蛋白去磷酸化参与了此凋亡过程     

Human Helper T Cell Lines Established by Coculture of Normal Human Cord Leukocytes with an HTLV-Il-infected Rabbit Leukocyte Cell Line (Ra-IIA)

Three helper T cell lines, designated CR -IIA (CR-IIA-1, CR-IIA- 2, and CR-IIA-3), were established by coculturing nor mal human cord leukocytes with a lethally irradiated HTLV II (human T lymphotropic virus type II)- infected rabbit leukocyte cell line (Ra-IIA). CR IIA had a normal human karyotype and expressed the surface markers CD3(+), CD4(+), CD8(-), CD19(-), CD25(+) and HLA- DR(+), confirming their helper T cell nature. CR- IIA cells were all free of Epstein- Barr virus nuclear antigen and were im-muno reactive with serum samples from HTLV- I- or HTLV-Il- infected patients and with anti HTLV- I, p19 or p24 anti body. The provirus genome of HTLV-II was detected in these cell lines by the polymerase chain reaction combined with a digoxigenin- enzyme- linked immunosorbent assay. Electron microscopy of CR-IIA-1 cells revealed a few im mature type C virus particles. These results suggest that HTLV- II was transmitted from the infected rabbit leukocyte cell line to human cord helper T lymphocytes with the development of immortalized HTLV - II- producing T cell lines. Acta Pathol Jpn 42: 347–352, 1992.     

全反式维甲酸对人乳腺癌MCF-7细胞凋亡的影响

目的:探讨全反式维甲酸(ATRA)对人乳腺癌MCF-7细胞凋亡的影响及作用途径.方法:在人乳腺癌细胞株MCF-7培养基中加入一定浓度ATRA和PKC-δ的专一抑制剂rottlerin(RO)并分组,通过SubG1assay by FACS、琼脂糖凝胶电泳检测基因组DNA ladder来观察ATRA对MCF-7的影响.结果:在浓度为5μM的ATRA作用下,MCF-7的凋亡率显著高于其它各组(P＜0.01),并可观察到明显梯状DNA.结论:ATRA能够诱导乳腺癌MCF-7细胞凋亡,但受PKC-δ的专一抑制剂RO的抑制.     

转染人OX40L细胞株的构建及其对T细胞共刺激作用的研究

为了构建稳定表达人OX4 0L基因的L92 9细胞株 ,初步研究OX4 0L信号通路对T细胞的共刺激效应。TRIzol一步法抽提人成熟DC总RNA ,RT PCR扩增出OX4 0L基因 ,双酶切装入逆转录病毒载体pEGZ Term ,与辅助病毒载体脂质体法共转染包装细胞 2 93T ,用其培养上清感染L92 9细胞 72h后 ,经Zeocin筛选出稳定表达OX4 0L分子的L92 9细胞株 ;采用3 H TdR掺入实验、细胞凋亡、细胞周期等方法研究OX4 0L信号对T细胞体外培养的共刺激作用。结果显示 ,成功地构建了含OX4 0L基因的重组逆转录病毒载体 ;经转染包装细胞 2 93T后 ,筛选获得能稳定高表达人OX4 0L蛋白的L92 9转基因细胞 ;OX4 0L转基因细胞对体外培养的T细胞具有促增殖、活化和抗凋亡的作用 ;同时 ,OX4 0 /OX4 0L信号与CD2 8/B7信号具有协同作用     

The Role of Endogenous Histamine on the Pathogenesis of the Lipopolysaccharide (LPS)-Induced, Acute Lung Injury: A Pilot Study

Abstract —Histamine is widely distributed in the lungs and increases capillary permeability and P-selectin expression. To observe the role of histamine in acute lung injury (ALI), we measured the histamine and protein concentrations and cell numbers in the bronchoalveolar lavage (BAL) of LPS-induced ALI in rats. We instilled LPS (3 mg/kg) intratracheally, in conjunction with the intravenous histamine receptor antagonists (mepyramine, a H1-receptor antagonist, or ranitidine, a H2-receptor antagonist). LPS increased protein concentration and neutrophil numbers in the BAL as well as myeloperoxidase (MPO) activity in lungs after 6 h. LPS also increased histamine concentration in BAL after 2 h. Mepyramine and ranitidine attenuated the increased histamine concentrations. Total cell number in the BAL and MPO activity in the lungs were significantly decreased and neutrophil numbers and protein concentration in the BAL seemed to decrease with the administration of ranitidine at 6 h. In conclusion, endogenous histamine might be involved in the recruitment of neutrophils and protein leaks in LPS-induced ALI via the H2 receptors.     

Upregulation of LAPTM4B‐35 Promotes Malignant Transformation and Tumorigenesis in L02 Human Liver Cell Line

Hepatocellular carcinoma (HCC) is one of the most frequent malignant neoplasms worldwide and is the second leading cause of cancer death in China. We have previously demonstrated that LAPTM4B‐35, encoded by lysosomal protein transmembrane 4 beta gene, is overexpressed in over 80% of HCCs and is a novel‐independent prognostic factor for metastasis, recurrence, and postoperative survival in HCC. In this study, we investigated the role of LAPTM4B‐35 in malignant transformation and tumorigenesis using L02 cells, a cell line originated from human normal liver cells. Our data show that replication‐deficient adenovirus vector‐mediated upregulation of LAPTM4B‐35 promotes anchorage‐independent proliferation and resistance to adriamycin‐induced apoptosis. Study of the underlying mechanisms demonstrated alterations of molecular events involved in these processes, which included the activation of phosphoinositide 3‐kinases (PI3K)/serine/threonine protein kinase B (PKB/AKT)/bcl‐xL/bcl‐2‐associated death promoter homolog (Bad) signaling pathway, inhibition of caspase‐3 activation, upregulation of Bcl‐2, and downregulation of Bax. In addition, upregulation of LAPTM4B‐35 in L02 cells resulted in tumorigenesis in 100% (6/6) of inoculated nude mice and accelerated the death of mice with xenografts in vivo. In conclusion, LAPTM4B‐35 promotes malignant transformation and tumorigenesis in human liver L02 cell line through promotion of deregulated proliferation and inhibition of apoptosis. These findings suggest that overexpression of LAPTM4B‐35 may play a critical role in hepatocarcinogenesis and therefore, may be a therapeutic target for HCC. Anat Rec, 2011. © 2011 Wiley‐Liss, Inc.     

HMME-PDT对人舌鳞癌Tca8113细胞的作用及影响因素初步研究

目的:初步探讨血卟啉单甲醚(HMME)介导的光动力疗法(HMME-PDT)对人舌鳞癌Tca8113细胞的作用及可能的影响因素。方法:以HMME作为光敏剂、发光二极管(LED)为光源的光动力疗法作用于Tca8113细胞。采用MTT法分别检测光敏剂孵育时间、光敏剂浓度、光剂量及光功率密度对Tca8113细胞抑制率的影响。HE染色观察细胞形态学改变,Hoechst 33342荧光染色观察细胞核凋亡情况。结果:细胞抑制率随光敏剂孵育时间延长而增大,呈时间依赖效应;并且随光敏剂浓度和光剂量增加而增大,呈浓度-光剂量依赖效应;在相同光剂量下,抑制率随光功率密度增加而增大,在高剂量时更明显。HE染色显示,与对照组相比,PDT处理组细胞密度明显降低,死细胞明显增多;Hoechst 33342荧光染色可见核染色质浓集、核固缩、核碎裂,出现凋亡小体,呈典型凋亡形态改变。结论:HMME-PDT能有效杀伤Tca8113细胞,光敏剂孵育时间、光敏剂浓度、光剂量及光功率密度以均是影响PDT疗效的重要因素,HMME-PDT主要通过凋亡方式诱导细胞死亡。     

HLA-G诱导T细胞免疫耐受的实验研究

用W6/ 3 2单抗对JEG 3细胞进行免疫荧光染色 ,可见在JEG 3细胞膜表面有高强度的黄绿色荧光。HLA G+的JEG 3细胞作为刺激细胞 ,观察其对淋巴细胞增殖反应的影响 ,结果JEG 3细胞不能刺激淋巴细胞增殖。采用经典的单向混合淋巴细胞培养的方法 ,以转染及未转染HLA G分子的K5 62细胞作为抑制细胞 ,按一定的比例加入反应体系 ,结果表明 ,转染HLA G的K5 62细胞能抑制淋巴细胞的增殖反应 ,该抑制以刺激细胞∶反应细胞∶抑制细胞的比例为 1∶1∶2时效果最明显 ,抑制率为 5 4 1% (P <0 0 1) ,转染空质粒和未转染HLA G的K5 62细胞均无明显抑制作用。外周血淋巴细胞与JEG 3细胞共同孵育 ,碘化丙啶 (PI)染色 ,流式细胞仪观察 ,结果发现 ,HLA G分子能诱导淋巴细胞的凋亡。     

The Anti-Tumor Effect and Biological Activities of the Extract JMM6 from the Stem-Barks of the Chinese Juglans Mandshurica Maxim on Human Hepatoma Cell Line Bel-7402

Juglans mandshurica Maxim is a traditional herbal medicines in China, and its anti-tumor bioactivities are of research interest. Bioassay-guided fractionation method was employed to isolate anti-tumor compounds from the stem barks of the Juglans mandshurica Maxim. The anti-tumor effect and biological activities of the extracted compound JMM6 were studied in BEL-7402 cells by MTT, Cell cycle analysis, Hoechst 33342 staining, Annexin V-FITC/PI assay and Detection of mitochondrial membrane potential (ΔΨm). After treatment with the JMM6, the growth of BEL-7402 cells was inhibited and cells displayed typical morphological apoptotic characteristics. Further investigations revealed that treatment with JMM6 mainly caused G2/M cell cycle arrest and induced apoptosis in BEL-7402 cells. To evaluate the alteration of mitochondria in JMM6 induced apoptosis. The data showed that JMM6 decreased significantly the ΔΨm, causing the depolarization of the mitochondrial membrane. Our results show that the JMM6 will have a potential advantage of anti-tumor, less harmful to normal cells. This paper not only summarized the JMM6 pick-up technology from Juglans mandshurica Maxim and biological characteristic, but also may provide further evidence to exploit the potential medicine compounds from the stem-barks of the Chinese Juglans mandshurica Maxim.