坏死性凋亡和p38 MAPK通路的相互作用介导高糖引起的H9c2心肌细胞损伤

目的研究坏死性凋亡(necroptosis,Nec)和p38丝裂原激活蛋白激酶(mitogen-activated protein kinase,MAPK)通路的相互作用在高糖引起H9c2心肌细胞损伤中的作用。方法应用细胞计数盒检测心肌细胞存活率;双氯荧光素染色荧光显微镜照相法检测细胞内活性氧(reactive oxygen species,ROS)水平;罗丹明123染色荧光显微镜照相法测定线粒体膜电位(mitochondrial membrane potential,MMP);蛋白质免疫印迹法测定RIP3蛋白(反映Nec的指标)和p38MAPK蛋白的表达水平。结果高糖(35 mmol·L~(-1)葡萄糖,HG)作用H9c2心肌细胞24 h可引起明显的细胞损伤,表现为细胞存活率降低,ROS生成及MMP丢失增多;应用100μmol·L~(-1)necrostatin-1(Nec-1,Nec特异性抑制剂)和HG共处理心肌细胞24 h或3μmol·L~(-1)SB203580(p38MAPK抑制剂)预处理心肌细胞60 min,再予HG作用24 h可减轻高糖引起的上述损伤。此外,HG作用心肌细胞1、3、6、9、12、24、36和48 h均能明显增加RIP3蛋白的表达水平,其中24 h时表达水平增加最明显。应用100μmol·L~(-1)Nec-1共处理或3μmol·L~(-1)SB203580预处理心肌细胞均能明显地抑制HG对RIP3蛋白表达的上调作用。另一方面,应用100μmol·L~(-1)Nec-1共处理心肌细胞能阻断HG对磷酸化(p)-p38MAPK表达的上调作用。结论 Nec和p38 MAPK通路的相互作用介导高糖引起H9c2心肌细胞损伤。     

尼可地尔对抗高糖引起的H9c2心肌细胞损伤和炎症反应

目的探讨尼可地尔(nicorandil,Nic)能否通过调控核因子-κB(nuclear factorκB,NF-κB)/环氧化酶-2(cyclooxygenase-2,COX-2)通路对抗高糖引起的H9c2心肌细胞损伤和炎症。方法应用细胞计数盒(CCK-8)检测心肌细胞存活率;蛋白质免疫印迹法测定NF-κB、COX-2和cleaved caspase-3蛋白的表达水平;乳酸脱氢酶(lactate dehydrogenase,LDH)试剂盒检测细胞培养液中LDH的活性;双氯荧光素染色荧光显微镜照相法测定胞内活性氧(reactive oxygen species,ROS)水平;Hoechst 33258核染色荧光显微镜照相法测定凋亡细胞数量;罗丹明123染色荧光显微镜照相法检测线粒体膜电位(mitochondrial membrane potential,MMP);ELISA法检测细胞培养液中白介素~(-1)β(IL~(-1)β)和肿瘤坏死因子-α(TNF-α)的水平。结果 35 mmol·L~(-1)葡萄糖(高糖,HG)作用H9c2心肌细胞24 h能明显降低心肌细胞存活率。在HG作用前,应用20~100μmol·L~(-1)Nic预处理60 min或50μmol·L~(-1)Nic预处理30~120 min均可明显对抗HG对心肌细胞存活率的抑制作用。另一方面,HG可上调心肌细胞磷酸化(p)-NF-κB p65和COX-2的表达,50μmol·L~(-1)Nic预处理心肌细胞60 min能抑制HG诱导的p-NF-κB p65和COX-2表达的上调。此外,HG作用心肌细胞24 h可引起明显的心肌细胞损伤和炎症反应,使培养液中LDH活性、ROS生成、凋亡细胞数量、cleaved caspase-3表达、MMP丢失及炎症因子IL~(-1)β和TNF-α的分泌均增加;在HG作用前,应用50μmol·L~(-1)Nic预处理心肌细胞60 min或应用100μmol·L~(-1)PDTC(NF-κB抑制剂)或10μmol·L~(-1)NS-398(COX-2抑制剂)和HG共处理心肌细胞24 h能明显拮抗HG引起的上述损伤和炎症反应。结论 Nic通过抑制NF-κB/COX-2通路对抗HG引起的H9c2心肌细胞损伤和炎症。     

淫羊藿苷对H_2O_2诱导的人脐静脉内皮细胞氧化损伤的保护作用及机制

目的研究淫羊藿苷(Ica)对H_2O_2诱导的人脐静脉内皮细胞(HUVEC)氧化损伤的保护作用及其机制。方法 H_2O_2诱导氧化损伤模型。药效学研究分为六组:空白组,模型组(750μmol·L-1 H2O2),Ica-L、M、H组(750μmol·L~(-1) H_2O_2+1×10-8、1×10-7、1×10-6mol·L~(-1)Ica)和溶媒组(0.1%DMSO)。Ica给药12 h后加入H_2O_2,Ica作用时间为24、36和48 h。Ica作用机制研究分为五组:空白组、模型组、Ica-H组、LY组(750μmol·L~(-1) H_2O_2+25μmol·L~(-1)LY294002)、Ica-H+LY组。LY294002为PI3K抑制剂,给予LY294002后2 h加入Ica,12 h后加入H_2O_2,Ica作用时间为48 h。MTT法检测细胞活力,ELISA检测细胞培养液中活性氧(ROS)的含量,显微镜观察细胞形态及存活细胞密度,Annexin V-FITC/PI染色荧光显微镜观察细胞凋亡率,Real time RT-PCR检测Bcl-2、Bax mRNA的表达,Western Blot检测p-Akt和Akt蛋白的表达。结果与空白组相比,模型组细胞活力降低(P<0.01),ROS分泌量和凋亡细胞增加(P<0.01);与模型组相比,Ica-L、M、H组均能提高细胞活力(P<0.01),降低细胞培养液中ROS的含量(P<0.05),其抑制率呈现时间和剂量依赖性。同时,Ica能明显降低细胞凋亡率(P<0.01),上调p-Akt蛋白和Bcl-2 m RNA的表达(P<0.05),下调Bax mRNA的表达(P<0.05);Ica的以上作用被LY294002拮抗。结论 Ica(1×10~(-8)-1×10-6 mol·L~(-1))对H_2O_2诱导的HUVEC氧化损伤有保护作用,能缓解氧化应激诱导的HUVEC凋亡,其机制与PI3K/Akt信号通路有关。     

麦冬皂苷D通过上调CYP2J3/EET减轻H_2O_2诱导的H9c2细胞氧化应激损伤（英文）

目的探讨麦冬皂苷D(OP-D)对H_2O_2诱导的H9c2细胞氧化应激损伤的保护作用及机制。方法通过H_2O_2诱导建立H9c2细胞氧化损伤模型,细胞分为正常对照组(予以无血清培养基培养28 h)、H_2O_2损伤模型组(H_2O_2400μmol·L~(-1)处理3 h)、OP-D 5,10和20μmol·L~(-1)预处理组(OP-D预处理24 h后+H_2O_2400μmol·L~(-1)处理3 h)、花生四烯酸CYP环氧酶活性抑制剂6-(2-炔丙基羟苯基)己酸(PPOH)干预组(OP-D20μmol·L~(-1)+PPOH 10μmol·L~(-1),PPOH于OP-D处理前1 h加入细胞)。MTT法测定细胞活性,酶联免疫吸附法(ELISA)检测环氧-二十碳-三烯酸(11,12-DHET和14,15-DHET)含量,ELISA法检测细胞内丙二醛(MDA)、一氧化氮(NO)含量及乳酸脱氢酶(LDH)、超氧化物歧化酶(SOD)活性,流式细胞术(FCM)检测活性氧(ROS)水平及细胞凋亡水平、Western印迹法检测细胞色素P450 2J3(CYP2J3)、磷酸化Akt(p-Akt)蛋白和磷酸化内皮型一氧化氮合酶(p-e NOS)蛋白在细胞中的表达,利用PPOH进一步验证OP-D减轻细胞氧化应激的可能内在机制。结果 H_2O_2400μmol·L~(-1)明显抑制H9c2细胞存活率(P<0.01),OP-D可明显增加H_2O_2损伤后细胞存活率(P<0.01);不同浓度OP-D增加11,12-DHET和14,15-DHET含量(P<0.05,P<0.01);OP-D增加H_2O_2损伤后细胞NO含量(P<0.05,P<0.01)、增强SOD活性(P<0.05)及降低MDA、LDH含量(P<0.05,P<0.01);OP-D显著降低H_2O_2损伤后细胞氧化应激及凋亡水平(P<0.05,P<0.01);OP-D预处理上调H_2O_2损伤后细胞CYP2J3蛋白和m RNA表达(P<0.05,P<0.01)、激活PI3K/Akt-e NOS通路的磷酸化水平(P<0.05,P<0.01);提前给予PPOH后,OP-D保护效应被抑制(P<0.05,P<0.01)。结论 OP-D能减轻H_2O_2所致的H9c2细胞损伤,可能是通过诱导CYP2J3表达及增加11,12-DHET和14,15-DHET含量,激活PI3K通路促进其下游因子Akt和e NOS磷酸化发挥作用。     

银杏二萜内酯葡胺注射液通过激活Akt/Nrf2通路抑制缺糖缺氧诱导的SH-SY5Y细胞的氧化应激损伤

目的探讨银杏二萜内酯葡胺注射液(DGMI)抑制缺糖缺氧(OGD)诱导人源性神经母细胞瘤细胞(SH-SY5Y)的氧化应激损伤及其机制。方法 SH-SY5Y细胞随机分为正常细胞对照组,OGD模型组,OGD 4 h+DGMI 25 mg·L~(-1)组,OGD 4 h+银杏叶提取物注射液(EGBLI)25 mg·L~(-1)组,OGD 4 h+银杏内酯注射液(LGBI)25 mg·L~(-1)组。药物作用6 h后,CCK-8法检测细胞存活,水溶性四唑盐1(WST-1)显色法法检测SOD活性,荧光探针法(DCFH-DA)检测ROS生成,Western蛋白印迹法检测细胞内血红素加氧酶(HO-1)、醌氧化还原酶(Nqo1)、蛋白激酶B(Akt)、磷酸化Akt(p-Akt)、细胞内核因子E2相关因子2(Nrf2)、磷酸化Nrf2(p-Nrf2)的表达;OGD 4 h+DGMI 25 mg·L~(-1)组加入PI3K抑制剂LY294002(终浓度为0,12.5,25和50μmol·L~(-1)),检测1 h后Akt,p-Akt,Nrf2和p-Nrf2的蛋白表达。结果与正常细胞对照组相比,OGD模型组SH-SY5Y细胞存活和SOD活性降低(P<0.01),ROS含量升高(P<0.01),降低p-Akt,Nrf2,p-Nrf2,HO-1和Nqo1的表达(P<0.01);与OGD模型组相比,OGD 4 h+药物组作用6 h,细胞存活率和SOD活性显著提高(P<0.01),ROS含量降低(P<0.05,P<0.01),p-Akt,Nrf2,p-Nrf2,HO-1和Nqo1蛋白表达水平提高(P<0.01),且DGMI 25 mg·L~(-1)效果优于EGBLI 25 mg·L~(-1)和LGBI 25 mg·L~(-1)(P<0.05,P<0.01);相较DGMI组,DGMI和LY294002作用1 h后p-Akt和p-Nrf2的表达被显著抑制(P<0.01),抑制效果呈浓度依赖性。结论 DGMI 25 mg·L~(-1)对OGD诱导的SH-SY5Y细胞具有抗氧化保护作用,其机制可能与激活Akt/Nrf2通路有关。     

缝隙连接蛋白43对人非小细胞肺癌HCC827细胞吉非替尼获得性耐药机制的初步研究

目的探讨缝隙连接蛋白43(connexin 43,Cx43)与非小细胞肺癌(NSCLC)细胞产生吉非替尼(Gefitinib)获得性耐药的关系。方法在Gefitinib敏感细胞株HCC827上,通过逐步递增Gefitinib浓度诱导获得Gefitinib耐药细胞株HCC827 GR;MTT法检测Gefitinib对HCC827/GR细胞的IC_(50);RT-PCR检测Cx43的mRNA水平;Western blot检测Cx43和磷酸化Akt(p-Akt)的蛋白水平;parachute荧光示踪法检测细胞缝隙连接功能(gap junction intercellular communication,GJIC);免疫荧光技术检测Cx43的细胞定位。结果Gefitinib作用于HCC827和HCC827 GR的IC_(50)分别为(0.07±0.019)μmol·L~(-1)、(10.84±0.021)μmol·L~(-1)(P<0.01);HCC827 GR中Cx43的mRNA和蛋白水平较HCC827明显降低(P<0.05),但p-Akt蛋白水平明显升高(P<0.05)。在HCC827 GR细胞上加PI3K的特异性抑制剂LY294002(25μmol·L~(-1),24 h)后,p-Akt蛋白水平明显下降(P<0.01),且Cx43的蛋白水平明显升高(P<0.01)。HCC827及HCC827 GR均未检测到GJIC,用GJIC增强剂RA(retinoic acid)处理(10μmol·L~(-1),24 h)上述细胞,亦未检测到荧光传递,免疫荧光结果显示Cx43表达在细胞胞质。结论胞质中Cx43的下调可能促进NSCLC细胞对Gefitinib的获得性耐药,其机制可能与Cx43非GJIC依赖的PI3K/Akt信号通路激活有关。     

坏死性凋亡介导化学性缺氧引起的HT22海马神经元损伤和炎症

目的探讨坏死性凋亡(necroptosis)是否参与化学性缺氧诱导的小鼠HT22海马细胞损伤和炎症。方法采用化学性缺氧模拟剂氯化钴(CoCl_2)作用HT22细胞建立化学性缺氧损伤的细胞模型。蛋白质免疫印迹法测定受体相互作用蛋白3(receptor interacting protein 3,RIP3)的水平;应用细胞计数试剂盒(cell counting kit-8,CCK-8)测定海马细胞的存活率;乳酸脱氢酶(lactate dehydrogenase,LDH)试剂盒检测细胞培养液中的LDH活性;罗丹明123染色荧光显微镜照相法检测线粒体膜电位(mitochondrial membrane potential,MMP);双氯荧光素染色荧光显微镜照相法测定胞内活性氧(reactive oxygen species,ROS)生成水平;ELISA法检测细胞培养液中白介素-1β(IL~(-1)β)和肿瘤坏死因子-α(TNF-α)的水平。结果 600μmol·L~(-1)CoCl_2作用HT22细胞36 h可产生明显的细胞毒性作用,使细胞存活率降至(52.0±2.65)%,成功建立化学性缺氧损伤的海马细胞模型;此外,CoCl_2可引起HT22细胞的多种损伤和炎症,表现为培养液中LDH活性升高,ROS过度生成,MMP丢失以及炎症因子(IL~(-1)β和TNF-α)分泌均增多。40~100μmol·L~(-1)坏死性凋亡抑制剂necrostatin-1(Nec-1)共处理可抑制CoCl_2引起的HT22细胞存活率降低,其中80μmol·L~(-1)时对细胞毒性的抑制作用最明显。同时,80μmol·L~(-1)Nec-1可对抗CoCl_2可引起HT22细胞的上述多种损伤和炎症。此外,CoCl_2处理HT22细胞6~48 h可促进RIP3的表达水平,Nec-1可明显抑制CoCl_2对RIP3表达的上调作用。结论坏死性凋亡介导化学性缺氧诱导的HT22海马神经元损伤和炎症。     

柚皮苷保护H9c2心肌细胞对抗阿霉素诱导的心肌毒性

目的探讨柚皮苷(NRG)能否保护H9c2心肌细胞对抗阿霉素(DOX)诱导的心肌毒性。方法应用DOX处理H9c2心肌细胞建立DOX心肌损伤模型。CCK-8比色法测定细胞存活率;谷胱甘肽试剂盒检测GSSG/(GSSG+GSH)的比值;Hoechst 33258核染色法观察细胞凋亡的形态学和数量改变;Western blot法测定葡萄糖调节蛋白78(GRP78)的表达水平;双氯荧光素(DCFH-DA)染色荧光显微镜摄片检测细胞活性氧(ROS)水平;罗丹明123(Rh123)染色荧光显微镜照像测定线粒体膜电位(MMP)。结果 DOX在3⁷μmol·L-1浓度范围内处理H9c2心肌细胞24 h,呈剂量依赖性降低细胞存活率,其中5μmol·L-1DOX能明显引起心肌细胞损伤,表现为使细胞存活率下降近50%,并呈时间依赖性上调GRP78蛋白的表达;1μmol·L-1NRG预处理60min可明显抑制5μmol·L-1DOX引起的心肌毒性作用,表现为细胞存活率升高,GSSG/(GSSG+GSH)的比值下降,凋亡细胞数目减少,GRP78表达被抑制,细胞内ROS产生及MMP丢失减少。结论 NRG能保护心肌细胞对抗DOX诱导的心肌细胞损伤,保护作用可能与其抗氧化应激及内质网应激有关。     

槲皮素通过调控PI3K/Akt信号通路对血管内皮祖细胞发挥保护作用

目的探讨槲皮素(quercetin,Que)对氧化应激情况下血管内皮祖细胞(endothelial progenitor cells,EPCs)的保护作用及其作用机制。方法分离并诱导分化人脐血EPCs,随机分为对照组;过氧化氢(H_2O_2)组:加入500μmol·L~(-1)的H_2O_2,建立氧化应激损伤EPCs模型;Que干预组:先分别加入浓度为60、90μmol·L~(-1)的Que预处理30 min后,再加500μmol·L~(-1) H_2O_2共同培养,培养12、24、48 h后,WST-1法观察EPCs增殖情况;Western blot检测Akt、磷酸化Akt的表达水平;实时荧光RT-PCR法检测PI3K、Akt3 mRNA的表达水平。结果与空白对照组对比,经过H_2O_2处理的EPCs增殖能力明显降低,且EPCs的Akt蛋白表达明显下降,PI3K、AKT3 mRNA明显下降(P<0.01,P<0.05)。加入60、90μmol·L~(-1) Que处理12、24、48 h后,损伤的EPCs细胞增殖能力明显增加,与模型组比较差异具有统计学意义(P<0.05)。同时明显升高EPCs磷酸化Akt的蛋白表达(P<0.05),以及PI3K、AKT3 mRNA表达(P<0.01)。结论槲皮素对H_2O_2诱导血管EPCs氧化应激损伤起到修复作用,其作用机制可能是通过激活PI3K/Akt信号通路,减少氧化应激对脑血管病灶的影响,促进脑血管EPCs增殖和分化。     

天麻素在甲基苯丙胺诱导SH-SY5Y细胞自噬中的作用及机制研究

目的研究天麻素(gastrodin)在甲基苯丙胺(methamphetamine,METH)诱导SH-SY5Y细胞自噬中的作用,并探讨其作用机制。方法体外培养人神经母细胞瘤SH-SY5Y细胞,不同浓度的METH(0.5、1.0、1.5、2.0、2.5、3.0 mmol·L~(-1))处理SY5Y细胞,并在6、12、24、48 h观察SY5Y细胞自噬的情况,确定自噬的最佳浓度和时间点。提前1 h给予1mmol·L~(-1)天麻素进行干预,用显微镜观察细胞形态变化,采用激光共聚焦显微镜观察LC3-Ⅱ的改变,Western blot检测天麻素干预前后LC3-Ⅱ、Beclin-1以及Akt、p-Akt、mTOR、p-mTOR的表达情况。结果随着METH浓度(0~3.0 mmol·L~(-1))的增加,SY5Y细胞逐渐变圆、突起逐渐变短、消失,同时部分细胞质内可见大小不等的空泡结构形成,细胞间隙逐渐增宽,最终细胞呈漂浮状态。随着METH浓度的增加,SY5Y细胞LC3-Ⅱ表达水平逐渐增强。激光共聚焦显微镜结果显示,天麻素+METH组LC3-Ⅱ的表达水平比METH组降低。与对照组相比,METH组LC3-Ⅱ和Beclin-1表达水平明显增强(P<0.01),mTOR和Akt差异无显著性,p-mTOR、p-Akt表达水平明显降低(P<0.01);给予天麻素干预后,与METH组相比,LC3-Ⅱ和Beclin-1表达水平降低,而mTOR、p-mTOR、Akt、p-Akt表达水平升高。结论 METH可诱导SY5Y细胞自噬,天麻素可减弱METH诱导的SY5Y细胞自噬,这一作用与天麻素调控Akt和mTOR信号通路密切相关。     

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.     

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     

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。     

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.     

Deoxynivalenol in cereals in Russia

A survey of the occurrence of deoxynivalenol (DON) and zearalenone (ZEN) in wheat, rye, barley and maize harvested in 1989-2001 in several regions of Russia has been conducted. A total of 5652 samples of cereals were analysed for DON and ZEN by using TLC and normal-phase HPLC with UV-detector. DON was detected in 69% of 2166 samples from Krasnodar region which is considered to be the major Fusarium endemic region of Russia. The contamination levels ranged from 0.1 till 8.6 ppm, MTEL was exceeded in 37% of these samples. The positive correlation between DON concentration and a percentage of Fusaria-damaged wheat kernels has been shown. DON occurrence and contamination levels were much lower that for wheat. Based on the results of monitoring and the data of average actual consumption of wheat products in Russia, the estimated daily intake of DON per 1 kg of body weight (EDI)was calculated. EDI varied from 0.07 ug in 1990-1991 till 1.40 ug in 1992. Although average EDI were lower than adopted tolerable daily intake (TDI, 3 ug/kg body weight) EDIs for the North-Caucasian region in some cases exceeded TDI.