塞来昔布对结肠癌HT-29细胞生长及骨桥蛋白表达的影响

目的 观察塞来昔布对结肠癌HT-29细胞的生长、凋亡和骨桥蛋白(OPN)表达的影响.方法 体外培养结肠癌HT-29细胞分为对照组和不同浓度塞来昔布干预组.MTT法检测细胞增殖抑制情况,流式细胞术分析细胞的凋亡,RT-PCR和免疫组化分析细胞中的OPN mRNA与OPN蛋白表达变化.结果 塞来昔布对HT-29细胞增殖有明显的时间与浓度依赖性抑制作用(P＜0.01).塞来昔布能诱导HT-29细胞凋亡,塞来昔布15、30和50μmol/L的细胞凋亡率分别为28.2％、32.8％和33.1％,均明显高于对照组的26.0％ (P＜0.05).药物干预组OPN mRNA及OPN蛋白表达明显低于对照组(P＜0.01).结论 塞来昔布可能通过抑制OPN表达而抑制结肠癌HT-29细胞的增殖,诱导其凋亡.     

瘦素对5-氟尿嘧啶损伤结肠癌细胞的影响

目的探讨不同浓度的瘦素对5-氟尿嘧啶(5-FU)损伤结肠癌细胞的影响。方法同时用5-FU及不同浓度的瘦素进行体外干预结肠癌HT-29细胞株。MTT法检测5-FU50%细胞生长抑制率(IC50)的变化。流式细胞仪、原位末端转移酶标记法(TUNEL)进行周期及凋亡分析。以RT-PCR方法检测caspase-9,caspase-3mRNA的表达。结果瘦素抑制5-FU对HT-29的杀伤作用。抑制5-FU诱导的细胞周期阻滞及细胞凋亡。RT-PCR表明加入瘦素后caspase-9,caspase-3mRNA的表达均下降,且呈剂量依赖性。结论瘦素通过下调caspase-9,caspase-3的表达促进结肠癌细胞产生凋亡抵抗,抑制5-FU的损伤作用。     

岩大戟内酯B通过阻断PI3K/Akt/NF-κB通路抑制结肠癌细胞的增殖和转移

目的:研究岩大戟内酯B(JB)对结肠癌HT-29细胞增殖和转移的抑制作用及其作用机制。方法:用不同浓度JB处理HT-29细胞,采用MTT法检测细胞增殖率;平板克隆实验检测细胞克隆形成率;流式细胞仪检测细胞周期变化;划痕实验分析细胞的迁移能力;Transwell小室实验研究细胞的侵袭能力;免疫荧光法和Western blotting法检测E-钙黏蛋白(E-cadherin)、N-钙黏蛋白(N-cadherin)、波形蛋白vimentin、锌指蛋白(Snail)1、Snail2、基质金属蛋白酶(MMP)-2和MMP-9蛋白的表达;Western blotting法检测p-PI3K、PI3K、p-Akt、Akt、NF-κB P65、p-NF-κB P65蛋白表达水平。100μg/L IGF-1组和100μg/L IGF-1+20μmol/L JB组分别处理HT-29细胞,Western blotting法检测PI3K/Akt/NF-κB通路相关蛋白表达变化。结果:JB抑制HT-29细胞增殖作用浓度依赖性,其作用24 h的IC 50为52.68μmol/L;JB呈浓度依赖性地降低HT-29细胞的克隆形成率(P<0.05);与对照组相比,JB处理后的HT-29细胞G0/G1期比例显著增高,S期细胞比例明显下降;JB可显著抑制HT-29细胞的体外迁移、侵袭能力(P<0.05);JB作用后的HT-29细胞E-cadherin蛋白水平升高,vimentin、Snail1、Snail2、N-cadherin、MMP-2、MMP-9、p-PI3K、p-Akt、p-NF-κB P65蛋白表达水平显著降低(P<0.05);IGF-1+JB组p-PI3K、p-Akt、与p-NF-κB P65蛋白的表达水平较IGF-1组显著下降(P<0.05)。结论:JB在体外能抑制HT-29细胞增殖,诱导细胞在G0/G1期阻滞,抑制HT-29迁移和侵袭,调控上皮-间质转化(EMT)及MMPs,其机制可能与阻断PI3K/Akt/NF-κB通路有关。     

白藜芦醇抑制结肠癌细胞系HT-29体外增殖作用的研究

目的通过观察白藜芦醇对结肠癌细胞系HT-29增殖的影响并检测程序性细胞死亡4蛋白表达水平,探讨白藜芦醇的抗结肠癌增殖作用及部分相关机制。方法 HT-29细胞经不同浓度白藜芦醇作用后,流式细胞术检测细胞周期分布及凋亡情况,Western blot法检测程序性细胞死亡4蛋白表达水平变化。结果不同浓度的白藜芦醇对HT-29细胞的增殖有抑制作用,并且呈现出一定的剂量依赖性(P<0.01),白藜芦醇改变细胞周期分布,细胞周期阻滞在S期,同时诱导HT-29细胞凋亡,试验组与空白对照组相比,S期细胞比例及凋亡率明显增高(P<0.05),细胞周期被阻滞,增殖抑制。白藜芦醇处理后HT-29细胞程序性细胞死亡4蛋白表达水平上调,与对照组比较,差异有统计学意义(P<0.01)。结论白藜芦醇能够显著抑制HT-29细胞株的增殖,细胞周期阻滞于S期,诱导肿瘤细胞凋亡,其肿瘤抑制作用可能与程序性细胞死亡4蛋白表达上调有关。     

DHA和EPA调控巨噬细胞表型抑制HT-29细胞生长

目的 探讨二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)通过调控巨噬细胞表型对HT-29细胞生长的影响。方法 人单核细胞株THP-1诱导成M2型巨噬细胞后,与人结肠癌细胞株HT-29共培养,分别向共培养体系中加入DHA或EPA 0、10、20、40μmol/L处理48 h。MTT法检测HT-29细胞增殖情况,ELISA法检测上清液中TNF-α、IL-6、IL-1β和IL-10水平,实时荧光定量PCR检测巨噬细胞中CD86、诱导型一氧化氮合酶(iNOS)、精氨酸酶1(Arg1)和CD206 mRNA表达,Western blot法检测HT-29细胞磷酸化NF-κB p65(p-NF-κB p65)、磷酸化信号转导和转录激活因子3(p-STAT3)和NOD样受体热蛋白结构域相关蛋白3(NLRP3)蛋白表达。结果 与DHA 0μmol/L比较,DHA 10、20、40μmol/L处理后HT-29细胞存活率降低,共培养上清液中TNF-α、IL-6、IL-1β水平升高,IL-10水平降低,巨噬细胞中CD86、iNOS mRNA表达升高,Arg1、CD206 mRNA表达降低,HT-29细胞中p...     

EGCG对TF/Ⅶa/PAR2促进SW620细胞增殖与迁移的干预作用

目的 探讨表没食子儿茶素没食子酸酯(EGCG)对组织因子(TF)/凝血因子Ⅶa/蛋白酶激活受体(PAR)2促进结肠癌细胞株SW620细胞增殖与迁移的干预作用.方法 用不同浓度EGCG、蛋白酶激活受体2激动剂(PAR2-AP)、Ⅶa刺激SW620细胞,采用MTT法、transwell法分别检测细胞增殖及迁移能力,实时定量PCR检测细胞TF及半胱天冬氨酸蛋白酶(Caspase)7 mRNA表达,发色底物法与Western blot分别检测TF活性、Caspase-7蛋白表达.结果 与PAR2-AP或Ⅶa单独处理相比,EGCG+PAR2-AP、EGCG+Ⅶa对SW620细胞增殖、迁移的促进作用明显降低,TFmRNA表达及活性下降,Caspase-7 mRNA及蛋白表达上调(P＜0.05).结论 EGCG可干预SW620细胞TF和Caspase-7的表达,抑制TF/Ⅶa/PAR2对细胞增殖与迁移的促进作用.     

5’-氮杂-2’-脱氧胞苷对结直肠癌细胞株HT-29和LoVo中MGMT基因甲基化状态、mRNA表达及蛋白表达的影响

目的探讨甲基化酶抑制剂5’-氮杂-2’-脱氧胞苷（5’-Aza-CdR）对结直肠癌（colorectal cancer,CRC）细胞株HT-29和LoVo中MGMT基因甲基化水平、mRNA及蛋白表达的影响。方法用0.5、1.0、1.5μmol/L浓度的5’-Aza-CdR处理CRC细胞株HT-29和LoVo。应用MethyLight方法、实时荧光定量PCR方法及蛋白印迹试验（Westernblot）检测药物处理前后HT-29和LoVo细胞中MGMT基因的甲基化状态、mRNA和蛋白表达情况。结果 MethyLight检测HT-29和LoVo细胞中MGMT蛋白在药物作用后异常甲基化得到逆转。实时荧光定量PCR检测5’-Aza-CdR浓度为0.5、1.0、1.5μmol/L组HT-29细胞株和LoVo细胞株MGMT基因mRNA表达水平均较对照组上调,Western blot检测5’-Aza-CdR浓度为0.5、1.0、1.5μmol/L组MGMT蛋白表达水平均较对照组上调,且均具有药物剂量依赖性（P〈0.05,P〈0.01）。结论 CRC细胞株HT-29和LoVo中MGMT基因启动子甲基化可能是导致该基因表达下调甚至失活的主要原因。5’-Aza-CdR能够逆转CRC细胞株HT-29和LoVo中MGMT基因的甲基化状态,并能恢复mRNA及蛋白重新表达。     

胰腺癌细胞中GDNF对MMP-9表达的影响

目的探讨胰腺癌细胞中胶质细胞源神经营养因子(GDNF)对基质金属蛋白酶(MMP)-9表达的影响。方法用DMEM培养基进行人胰腺癌细胞株MIAPaCa-2和Capan-2细胞培养,利用RT-PCR、Westernblot和ELISA法研究胰腺癌细胞中GDNF对MMP-9mRNA及蛋白表达的影响。结果 RT-PCR实验发现胰腺癌细胞中GDNF能上调MMP-9mRNA的表达,Westernblot法、ELISA法检测结果表明胰腺癌细胞中GDNF能上调MMP-9蛋白的表达,且于GDNF浓度为100μg/L,作用48h时达最大值。结论 GDNF具有上调胰腺癌细胞MMP-9表达的作用,从而增强胰腺癌细胞的侵袭能力。     

Six1蛋白对在结肠癌细胞株HT-29增殖能力影响的实验研究

目的 研究高表达Six1对人结肠癌细胞株HT-29增殖能力的影响.方法 运用慢病毒构建高表达Six1的HT-29稳定细胞株,应用Western blot方法、MTT比色法、BrdU法检测Six1的蛋白表达.结果 成功构建Six1表达的HT-29Six1+细胞,实验组HT-29Sux1+细胞Six1蛋白表达量为对照组HT-29con的4.3倍;采用MTT法,以第1天的吸光度A值作为参照标准,HT-29Six1+组高于HT-29con组(第2天为2.35±0.68 vs 1.03±0.67,第3天为6.33±0.60 vs 2.44±1.01,第4天为14.70±1.40 vs4.60±1.30,第5天为20.60±2.40 vs 9.25±1.60),从第3天开始,差异有统计学意义(P＜0.05).采用BrdU法HT-29Six1+组的比例高于HT-29con组[(45.97±1.21)％ vs (29.56±1.05)％],差异有统计学意义(P＜ 0.05).结论 HT-29Six1+细胞株稳定高表达Six1,高表达Six1可以增强HT-29细胞的增殖能力.     

5′-氮杂-2′-脱氧胞苷对 HT-29和 LoVo结直肠癌细胞株中 p16基因甲基化状态、mRNA表达及蛋白表达的影响

目的：探讨甲基化酶抑制剂5′-氮杂-2′-脱氧胞苷（5′-Aza-2′-deoxycytidine,5′-Aza-CdR）对结直肠癌细胞株HT-29和Lo-Vo中p16基因甲基化状态、mRNA及蛋白表达的影响。方法应用TaqMan探针为基础的实时定量PCR法、SYBR Green PCR法及蛋白印迹实验（ Western blot ）检测不同浓度5′-Aza-CdR处理前后HT-29和LoVo细胞中p16基因的甲基化状态、mRNA和蛋白表达。结果 TaqMan 探针为基础的实时定量PCR法检测HT-29和LoVo细胞中p16蛋白在药物作用后异常甲基化得到逆转;实时荧光定量PCR和Western Blot检测到0．5、1．0、1．5μM 5′-Aza-CdR处理后p16基因mRNA和蛋白均重新表达,具有统计学意义（P均＜0．05）。结论结直肠癌细胞株HT-29和LoVo中p16启动子甲基化可能是导致该基因表达下调甚至失活的主要原因。5′-Aza-CdR能够较成功的逆转结直肠癌细胞株HT-29和LoVo中p16基因的甲基化状态,并能恢复mRNA及蛋白重新表达。     

Quantitative in vivo and in vitro sex differences in artemisinin metabolism in rat

1. The pharmacokinetics of the antimalarial compound artemisinin were compared in the male and female Sprague-Dawley rat after single dose i.v. (20 mg.kg) or i.p. (50 mg.kg) administration of an emulsion formulation. 2. Plasma clearance of artemisinin was 12.0 (95% confidence interval: 10.4, 13.0) l.h. kg in the male rat and 10.6 (95% CI: 7.5, 15.0) l.h. kg in the female rat suggesting high hepatic extraction in combination with erythrocyte uptake or clearance. Artemisinin half-life was 0.5 h after both routes of administration in both sexes. Values for plasma clearance and half-lives did not statistically differ between the sexes. 3. After i.p. administration artemisinin AUCs were 2-fold higher in the female compared with male rat (p 0.001). Artemisinin disappearance was 3.9-fold greater in microsomes from male compared with female livers and it was inhibited in male microsomes by goat or rabbit serum containing antibodies against CYP2C11 and CYP3A2 but not CYP2B1 or CYP2E1. 4. The unbound fraction of artemisinin in plasma was lower (p 0.001) in plasma obtained from the male (8.8 2.0%) compared with the female rat (11.7 2.2%). 5. The possibility of a marked sex difference, dependent on the route of administration, has to be taken into account in the design and interpretation of toxicological studies of artemisinin in this species.     

Quantitative in vivo and in vitro sex differences in artemisinin metabolism in rat

1. The pharmacokinetics of the antimalarial compound artemisinin were compared in the male and female Sprague-Dawley rat after single dose i.v. (20 mg x kg(-1)) or i.p. (50 mg x kg(-1)) administration of an emulsion formulation. 2. Plasma clearance of artemisinin was 12.0 (95% confidence interval: 10.4, 13.0) 1 x h(-1) x kg(-1) in the male rat and 10.6 (95% CI: 7.5, 15.0) 1 x h(-1) x kg(-1) in the female rat suggesting high hepatic extraction in combination with erythrocyte uptake or clearance. Artemisinin half-life was approximately 0.5 h after both routes of administration in both sexes. Values for plasma clearance and half-lives did not statistically differ between the sexes. 3. After i.p. administration artemisinin AUCs were 2-fold higher in the female compared with male rat (p < 0.001). Artemisinin disappearance was 3.9-fold greater in microsomes from male compared with female livers and it was inhibited in male microsomes by goat or rabbit serum containing antibodies against CYP2C11 and CYP3A2 but not CYP2B1 or CYP2E1. 4. The unbound fraction of artemisinin in plasma was lower (p < 0.001) in plasma obtained from the male (8.8 +/- 2.0%) compared with the female rat (11.7 +/- 2.2%). 5. The possibility of a marked sex difference, dependent on the route of administration, has to be taken into account in the design and interpretation of toxicological studies of artemisinin in this species.     

休克时血中氧自由基的变化

本实验测定10名休克患者血浆和红细胞的丙二醛(MDA)、血浆总抗的氧化活性(AOA)的含量。结果表明:休克病人红细胞膜和血浆 MDA 含量(4.298±0.722;5.348±0.834)与对照组(3.235±0.682;4.356±1.081)比较明显增高(P<0.05);血浆 AOA(39.65±7.858)与对照组(48.21±10.81)比较明显降低(P<0.01)。提示:休克时,患者机体内自由基反应增强是引起组织细胞损伤的原因之一。     

Interindividual variability in metabolic activation in humans in vivo

In assessing interindividual variability in metabolic activation, the toxic metabolite is often too unstable for conventional analysis. Possible alternatives include a stable product of the reactive metabolite e.g. cysteinyl derivatives of N-acetyl-4-benzoquinoneimine, the toxic metabolite of paracetamol, adducts with DNA or protein, and indirect measurement of the activity of the enzyme(s) producing the active metabolite. An example of the last approach is the use of furafylline, a highly specific inhibitor of human CYP1A2, to determine the extent of the metabolic activation of the cooked food mutagens PhIP and MeIQx. The extent of inhibition, determined from levels of unchanged amine in urine, is an indirect measure of the activity of the activation pathway. Further refinement of this approach, allied to improved measures of the biological process of interest should prove of value in evaluating interindividual variability and its role in the risk assessment process.     

Theophylline kinetics in peripheral tissues in vivo in humans

Several biochemical and cellular effects have been described for methylxanthines under in vitro conditions. However, it is unknown, whether threshold concentrations required to exert these effects are attained in target tissues in vivo. We therefore employed the microdialysis technique for measuring theophylline concentrations in peripheral tissues under in vivo conditions.Following in vitro and in vivo calibration, microdialysis probes were inserted into the medial vastus muscle and into the periumbilical subcutaneous adipose layer of healthy volunteers. Following single oral dose administration of 300 mg or i.v. infusion of 240 mg theophylline, in vivo time courses of theophylline concentrations were monitored in tissues and plasma. Major pharmacokinetic parameters (c_max, t_max, AUC) were calculated for plasma and tissue time courses. The mean AUC_tissue /AUC_plasma-ratio was 0.56 (p.o.) and 0.55 (i.v.) for muscle and 0.55 (p.o.) and 0.72 (i.v.) for subcutaneous adipose tissue.We conclude that microdialysis provides important information on the distribution and the tissue pharmacokinetics of theophylline.Abbreviations FPIA Fluorescence polarisation immuno assay - AUC Area under the curve - t_max Time to peak concentration - c_max Peak concentration     

Changes in angiopoietin expression in glomeruli involved in glomerulosclerosis in rats with daunorubicin-induced nephrosis

AIM: To study the potential pathological role of endogenous angiopoietins in daunorubicin-induced progressive glomerulosclerosis in rats. METHODS: Seventy male Wistar rats were allocated randomly into a daunorubicin group (DRB; n=40) or a control group (n=30). The rats in the DRB group were injected with DRB (15 mg/kg), in their tails. Subsequently, at intervals of 1, 2, 4, 6, 8, and 12 weeks, 5 male Wistar rats in each group were chosen randomly for 24 h urinary protein quantitative measurements (24 h UPQM), and determination of plasma tumor necrosis factor alpha (TNF-alpha), angiopoietin-1 (Ang1), and angiopoietin-2 (Ang2) levels. Kidney sections were examined by electron microscopy, Periodic Acid Schiff (PAS) staining, immunohistochemical staining and in situ hybridization histochemistry. RESULTS: As glomerulosclerosis progressed in the DRB group, expression of Ang1 mRNA and protein in glomeruli decreased and expression of TNF-alpha protein, Ang2 mRNA and protein in glomeruli increased. Expression of Ang1 mRNA and protein in glomeruli were negatively correlated with 24 h UPQM, Fn protein expression, and mean area of extracellular matrix (MAECM). In comparison, expression of Ang2 mRNA and protein in glomeruli were positively correlated with 24 h UPQM, Fn protein expression and MAECM; furthermore, there was a positive correlation between plasma Ang2 and 24 h UPQM. Plasma TNF-alpha and expression of TNF-alpha in glomeruli were positively correlated with expression of Ang2 mRNA and protein in glomeruli. There was a negative correlation between Ang1 protein expression and Ang2 protein expression in glomeruli. CONCLUSION: During DRB-induced glomerulosclerosis, podocyte injury led to a shift in the balance of Ang1 and Ang2 in glomeruli. Increased TNF-alpha in plasma and glomeruli may upregulate Ang2 expression in glomeruli. Elevated Ang2 in both plasma and glomeruli may mediate protein permeability through the glomerular filtration barrier. Moreover, local expression of Ang2 may facilitate the progress of glomerulosclerosis by upregulating a component expression of extracellular matrix.