红景天苷对低氧环境下大鼠阴茎海绵体平滑肌细胞缝隙连接蛋白43表达的影响

目的:探讨红景天苷对低氧环境下SD大鼠阴茎海绵体平滑肌细胞(CCSMC)缝隙连接蛋白43(Cx43)表达的影响。方法:体外培养SD大鼠CCSMC,免疫组化法鉴定细胞;设常氧对照组(21%O_2)、低氧组(1%O_2)、低氧+红景天苷8μg/ml组、低氧+红景天苷16μg/ml组、低氧+红景天苷32μg/ml组和低氧+红景天苷64μg/ml组,分别培养48 h;Western印迹测定Cx43相对表达量。结果:体外培养CCSMC生长良好,抗α-平滑肌肌动蛋白(α-SMA)和抗desmin抗体免疫组化染色阳性,CCSMC占比90%以上。MTT法结果显示,红景天苷浓度≤64μg/ml时,对CCSMC无明显毒性;而128μg/ml和256μg/ml红景天苷对CCSMC有一定的抑制作用。未加红景天苷干预时,与常氧对照组相比,低氧组Cx43总蛋白和磷酸化蛋白表达均显著升高(P0.01和P0.05),磷酸化比例未见明显变化(P0.05);与低氧不加药组相比,不同浓度红景天苷干预后Cx43表达量仍显著升高,但Cx43蛋白磷酸化比例显著降低,差异均有显著性(P均0.05)。结论:低氧促进大鼠CCSMC Cx43表达升高,红景天苷浓度≤64μg/ml无法逆转上述缺氧改变,但降低了Cx43磷酸化比例。推测红景天苷能通过降低Cx43磷酸化比例抑制缺氧引起的缝隙连接通道形成,保护平滑肌细胞功能。     

红景天苷对低氧环境下大鼠阴茎海绵体平滑肌细胞α-肌动蛋白和骨桥蛋白表达的影响

目的:探讨红景天苷对低氧SD大鼠阴茎海绵体平滑肌细胞(CCSMC)α-肌动蛋白、骨桥蛋白(OPN)表达的影响。方法:体外培养SD大鼠CCSMC,免疫组化法鉴定细胞;设正常对照组(21%O2浓度)、低氧组(1%O2浓度)、低氧+红景天苷1 mg/L组、低氧+红景天苷3 mg/L组、低氧+红景天苷5 mg/L组、低氧+前列腺素E1(PGE1)0.4μg/L组,分别培养48 h;RT-PCR法分别测定各组α-肌动蛋白、OPN的相对表达量。结果:体外培养的CCSMC生长良好,抗平滑肌α-肌动蛋白单克隆抗体免疫组化染色阳性;与正常对照组比较,低氧组细胞的α-肌动蛋白表达量下降、OPN表达量升高(P<0.01);与低氧组比较,红景天苷5 mg/L组α-肌动蛋白表达量升高、OPN表达量降低(P<0.01),与PGE1作用相当(P﹥0.05)。结论:低氧可引起SD大鼠CCSMC收缩型标志物α-肌动蛋白表达降低,合成型标志物OPN表达升高,推测低氧可能引起CCSMC由收缩型向合成型转化。红景天苷能抑制低氧引起的CCSMCα-肌动蛋白表达降低、OPN表达升高,浓度为5 mg/L时与PGE1作用几乎相当。     

二苯乙烯苷对H2O2诱导的MC3T3-E1凋亡的保护作用及机制研究

目的研究二苯乙烯苷(tetrahydroxystilbene glucoside,TSG)对氧化应激导致的成骨前体细胞MC3T3-E1凋亡的保护作用,并初步探讨相关机制。方法不同浓度TSG预处理MC3T3-E1 24 h后,300μmol/L H_2O_2作用24 h。实验分组:①空白对照组;②单纯H_2O_2处理组;③H_2O_2+TSG 0.1μmol/L处理组;④H_2O_2+TSG 1μmol/L处理组;⑤H_2O_2+TSG 10μmol/L处理组;⑥阳性对照抗氧化剂NAC 1 mmol/L处理组,通过MTT法、Hoechst33258染色来评价细胞凋亡情况及TSG对氧化损伤的保护作用;利用荧光酶标仪和MDA检测试剂盒来检测细胞中ROS及MDA的水平来评价细胞的氧化应激状态;Western-blot和RT-PCR分别从蛋白水平和基因水平评价Bcl-2和Bax的表达水平。结果单纯H_2O_2处理可以导致细胞死亡,显微镜下可见许多细胞死亡,脱壁;Hoechst33258染色可见有较多的细胞出现核固缩、核浓集现象;不同浓度的TSG预处理后,细胞凋亡现象得到改善。单独H_2O_2作用可以导致成骨前体细胞出现较大程度的凋亡,不同浓度TSG预处理后,细胞凋亡率有所降低;单纯H_2O_2作用可以导致细胞水平的ROS和脂质氧化产物MDA产生增加,TSG(1～10μmol/L)可以显著降低细胞水平ROS和MDA水平(P0.05),改善细胞的氧化应激状态;Western-blotting和实时定量RT-PCR结果 TSG预处理可以减少H_2O_2处理后,促凋亡蛋白Bax的表达,增加抗凋亡蛋白Bcl-2的表达。结论氧化应激可以导致成骨前体细胞MC3T3-E1凋亡增加,TSG可以通过降低氧化应激水平。其机理可能是TSG通过促凋亡蛋白Bax的表达及增加抗凋亡蛋白Bcl-2的表达起到保护作用。     

辛伐他汀对前列腺上皮细胞RWPE-1增殖及凋亡的影响

目的:探讨辛伐他汀对前列腺上皮细胞RWPE-1增殖及凋亡的影响。方法:设定不同浓度的辛伐他汀(0、10、20、40μmol/L)分别作用于体外培养的RWPE-1细胞,利用MTT法检测细胞增殖情况,流式细胞术检测细胞的凋亡情况。荧光定量RT-PCR检测RWPE-1细胞的Bcl-2、Bax、Cx43 mRNA的表达,Western印迹检测Bcl-2、Bax、Cx43蛋白的表达。结果:MTT法检测辛伐他汀(10、20、40μmol/L)作用于RWPE-1细胞72 h后,对RWPE-1细胞的抑制率分别为(21.07±6.41)%、(34.87±9.65)%和(47.18±10.88)%,与对照组[(1.21±0.54)%]比较有显著差异(P0.05),并且呈明显的剂量依赖关系(P0.05);处理72 h后各组的凋亡指数分别为:10μmol/L组(0.066±0.016)%,20μmol/L组(0.126±0.023)%,40μmol/L组(0.192±0.025)%,与对照组[(0.015±0.005)%]相比差异显著(P0.01),且呈剂量依赖关系(P0.05)。荧光定量PCR检测显示随着辛伐他汀浓度升高Bcl-2基因表达逐渐下调(P0.05),Bax和Cx43基因表达逐渐上调(P0.05),并且呈剂量依赖关系(P0.05)。Western印迹检测显示RWPE-1细胞内Bcl-2蛋白的表达随辛伐他汀浓度的增高逐渐下调(P0.05),Bax蛋白逐渐上调(P0.05),Cx43蛋白逐渐上调(P0.01),并且皆呈剂量依赖关系(P0.05)。Cx43的表达与Bcl-2的表达呈负相关,与Bax的表达呈正相关。结论:辛伐他汀可能通过影响细胞间隙连接通讯来抑制前列腺上皮细胞增殖并诱导其凋亡。     

红景天苷对缺氧肾小管上皮细胞Toll受体2、IL-6表达及其凋亡的影响

目的:观察红景天苷(salidroside Sal.)对氯化钴(cobaltous chloride,Co Cl2·6H2O)诱导的缺氧人肾小管上皮细胞(human kidney tubular epithelia cell,HKC)Toll样受体2(toll-like receptor 2,TLR-2)表达、白细胞介素-6(interleukin-6,IL-6)的分泌及细胞凋亡的影响。方法:HKC细胞置于六孔板培养,随机分为正常对照组、缺氧模型组、红景天苷(salidroside Sal.)干预组(25μg/ml、50μg/ml、100μg/ml)。其中缺氧模型采用300μmol/L氯化钴处理6 h得到,红景天苷干预组在此模型基础上再用不同浓度的红景天苷处理缺氧细胞24 h。RT-PCR和Western blot检测TLR-2的表达,ELISA检测各组细胞上清中IL-6含量,流式细胞仪检测缺氧HKC凋亡情况。结果:氯化钴诱导HKC TLR-2蛋白(P<0.05)及RNA表达上调(P<0.01)、IL-6分泌增加(P<0.01)及细胞凋亡增加(P<0.01)。25μg/ml和50μg/ml的红景天苷能降低缺氧HKC细胞IL-6的水平(P<0.01),50μg/ml红景天苷抑制作用强于25μg/ml(P<0.05)。与缺氧模型组比较,尽管100μg/ml红景天苷能降低缺氧HKC细胞IL-6的绝对值水平,但差异无统计学意义(P>0.05)。25μg/ml,50μg/ml和100μg/ml红景天苷均能抑制TLR-2蛋白表达(P<0.01),且100μg/ml较25μg/ml红景天苷抑制作用显著(P<0.05),但25μg/ml与50μg/ml、50μg/ml与100μg/ml红景天苷比较,它们抑制作用的强弱差异无统计学意义(P>0.05)。三种浓度的红景天苷也能抑制缺氧HKC TLR-2的RNA表达(P<0.01),50μg/ml及100μg/ml红景天苷抑制作用强于25μg/ml红景天苷(P<0.05),但50μg/ml与100μg/ml红景天苷比较,二者抑制作用差异无统计学意义(P>0.05)。50μg/ml和100μg/ml红景天苷能抑制缺氧HKC凋亡(P<0.01),但25μg/ml红景天苷未表现出抑制凋亡的作用(P>0.05),50μg/ml与100μg/ml红景天苷比较,两者抑制凋亡的作用差异无统计学意义(P>0.05)。结论:红景天苷对缺氧HKC的TLR-2蛋白及RNA表达、IL-6的分泌及细胞凋亡均有抑制作用,但其抑制效应呈现非剂量依赖性。     

褪黑素对老化卵母细胞体外发育能力的改善效果评价

目的探讨体外培养阶段(IVC)添加褪黑素(MT)对卵母细胞老化引起发育受损的改善效果。方法采用不同浓度的过氧化氢(H_2O_2)处理小鼠MII期卵母细胞诱导老化,浓度分别为0(对照组)、10、50、100、150μmol/L,体外受精(IVF)后统计各组二细胞率、囊胚形成率,检测老化卵母细胞的线粒体活性及丰度(Mitotracker Red、JC-1)、活性氧(ROS)水平、线粒体拷贝数等指标;在100μmol/L H_2O_2处理条件下,老化卵母细胞在IVF后的培养阶段分别添加不同浓度褪黑素(10-5、10-7、10-9 mol/L),统计二细胞率、囊胚率,并且分别检测各组获得囊胚的细胞数及凋亡率。结果不同浓度H_2O_2诱导卵母细胞老化后,囊胚发育率随H_2O_2浓度的升高而降低,50μmol/L和100μmol/L H_2O_2组囊胚形成率分别为(26.27±0.06)%和(28.46±3.45)%,相比对照组的(34.90±1.77)%显著降低,差异有统计学意义(P0.05);在H_2O_2诱导老化卵母细胞中,100μmol/L、150μmol/L H_2O_2浓度时,ROS水平相比对照组显著升高,差异具有统计学意义(P0.05);而活性线粒体的丰度及拷贝数呈现下降趋势,膜电位呈上升趋势,但相比对照组无显著性差异(P0.05);100μmol/L H_2O_2处理诱导卵母细胞老化后,在培养液中添加10-9 mol/L褪黑素组与老化对照组相比,囊胚率[(29.42±2.39)%vs.(20.87±4.12)%]、囊胚细胞数(39.36±9.78vs.37.91±4.25)均显著升高,凋亡率显著下降(2.57%vs.3.18%),差异均有统计学意义(P0.05);并且这些指标均达到与未经老化处理组的相似发育水平。结论老化卵母细胞体外受精后发育率和发育质量偏低的现象,可以通过在受精后体外培养阶段添加褪黑素得到改善。     

缝隙连接蛋白43在淫羊藿苷成骨诱导中的作用研究

[目的]探讨缝隙连接蛋白43(Cx43)在淫羊藿苷(ICN)诱导人骨髓间充质干细胞(MSCs)成骨分化中的作用。[方法]密度梯度离心法体外分离培养MSCs,取第三代细胞实验,流式细胞仪测定细胞表面标记物。实验分四组:(1)空白对照组,(2)成骨诱导组,(3)1-庚醇组,(4)ICN组。MTT检测不同时间点2.5μmol/L 1-庚醇的细胞毒作用。分别用含0、10-9mol/L ICN、10-9mol/L ICN+2.5μmol/L 1-庚醇的成骨诱导液(ODM)诱导培养14 d后,实时定量PCR检测各组成骨相关基因及Cx43的表达情况,Western blot检测MSCs成骨分化过程中Cx43蛋白的表达情况,碱性磷酸酶(ALP)定量测定各组细胞ALP含量。[结果]细胞高表达CD13、CD44,低表达CD14、CD45。2.5μmol/L 1-庚醇对细胞没有明显的毒性抑制作用。ICN诱导14 d后I型胶原、ALP、骨钙素(OCN)、RUNX2及Cx43的表达显著增加。2.5μmol/L 1-庚醇干预后I型胶原、ALP、RUNX2及OCN表达明显减弱,但仍高于空白对照组及成骨诱导组,其中Cx43的表达无明显变化。ALP定量分析结果显示ICN能促进ALP合成与分泌,其含量显著高于其他三组,但ICN的成骨诱导作用部分被1-庚醇所阻断。[结论]Cx43介导的缝隙链接细胞间通讯在ICN诱导成骨过程中起着很重要作用。     

红景天苷对低氧诱导大鼠海绵体平滑肌细胞凋亡的抑制作用

目的:探讨红景天苷对低氧诱导的大鼠海绵体平滑肌细胞(CCSMCs)凋亡的影响。方法:采用酶消化法体外培养大鼠CCSMCs,抗α-平滑肌肌动蛋白(α-SMA)和结蛋白(Desmin)免疫荧光鉴定CCSMCs纯度;通过MTT法筛选红景天苷无毒剂量;以低氧混合气体(1%O2,5%CO2,94%N2)通入缺氧小室建立细胞低氧模型;细胞分为3组:正常组,低氧组,红景天苷(32μg/ml)干预组,采用流式细胞术观察各组CCSMCs凋亡的情况,Western印迹检测caspase-3蛋白表达水平。结果:成功培养大鼠CCSMCs,免疫荧光显示绝大部分细胞α-SMA、Desmin阳性;≤32μg/ml的红景天苷对细胞无明显的毒性;低氧组CCSMCs早期凋亡[(18.69±1.29)%]较正常组[(12.77±1.41)%]明显增多(P0.01),低氧组晚期凋亡[(21.03±1.53)%]较正常组[(14.63±2.00)%]亦增加(P0.05),同时,活化型caspase-3蛋白表达上升(P0.01);32μg/ml红景天苷剂量下可有效降低低氧诱导的CCSMCs早期凋亡率[(13.46 1.87)%](P0.01),活化型caspase-3蛋白表达下降(P0.01)。结论:红景天苷能够降低低氧诱导的CCSMCs活化型caspase-3蛋白的表达,抑制了低氧诱导的CCSMCs凋亡。     

红景天苷通过JAK2/STAT3通路抑制退变髓核细胞的炎症反应和凋亡

目的观察红景天苷对退变髓核细胞凋亡和炎症反应的影响,并探究其与JAK2/STAT3信号通路的关系。方法通过氧糖剥夺(oxygen glucose deprivation,OGD)培养建立退变髓核细胞模型,退变细胞分别予浓度为10μg/mL、30μg/mL和50μg/mL的红景天苷培养液。后续实验选择30μg/mL浓度进行,分为Control组、OGD组、红景天苷组、AG490(JAK2/STAT3信号通路抑制剂)组和红景天苷联合AG490干预组。RT-PCR法检测髓核细胞蛋白聚糖(Aggrecan)和Ⅱ型胶原(Col2a1)表达水平;Western blot检测红景天苷对髓核细胞p-JAK2和p-STAT3蛋白水平的影响;ELISA检测上清液中炎症相关因子TNF-α、IL-1β和IL-6的表达水平,流式细胞术检测髓核细胞的凋亡。结果与Control组相比,OGD组Aggrecan和Col2a1 mRNA表达明显降低,炎症相关因子TNF-α、IL-1β和IL-6水平升高,p-JAK2和p-STAT3的蛋白水平明显上调。与OGD组相比,红景天苷组显著抑制细胞凋亡以及炎症相关因子TNF-α、IL-1β和IL-6的释放,同时,我们发现,AG490组和红景天苷联合AG490干预组上述指标均明显降低,其中红景天苷联合AG490干预组各检测指标较AG490组略低。红景天苷联合AG490干预明显改善髓核细胞的凋亡和炎症反应,并抑制JAK2和STAT3的磷酸化水平。结论红景天苷可能通过抑制JAK2/STAT3信号通路的活化而减轻退变髓核细胞炎症因子的产生和细胞凋亡。     

益肾方对大鼠肾小管上皮细胞氧化应激的保护作用及其机制研究

目的:探究益肾方对NRK-52E细胞氧化损伤的保护作用。方法:建立H_2O_2诱导NRK-52E氧化损伤模型,分为正常对照组,H_2O_2模型组,益肾方组。流式细胞术测定细胞凋亡率,运用Western-blot技术检测Caspase-3和BCL-2的蛋白表达。结果:与正常对照组比较,H_2O_2造模组的细胞凋亡率明显增高(P 0. 01);与H_2O_2模型组比较,益肾方组在益肾方浓度100μg/ml、200μg/ml、400μg/ml时,细胞的凋亡率出现明显的下降(P 0. 05)。与H_2O_2模型组相比,益肾方组在益肾方浓度100μg/ml、200μg/ml时,Caspase-3的蛋白表达明显降低,BCL-2的蛋白表达增加(P 0. 05)。结论:益肾方对NRK-52E细胞氧化损伤的保护机制,可能与其降低细胞凋亡,同时下调Caspase-3和上调BCL-2的蛋白表达有关。     

Evaluation of the association of IGF2BP2 variants with type 2 diabetes in French Caucasians

OBJECTIVE—We performed a comprehensive genetic association study of common variation spanning the IGF2BP2 locus in order to replicate the association of the “confirmed” type 2 diabetes susceptibility variants rs4402960 and rs1470579 in the French Caucasian population and to further characterize the susceptibility variants at this novel locus.RESEARCH DESIGN AND METHODS—We genotyped a total of 21 tagging single nucleotide polymorphisms spanning the IGF2BP2 locus in our type 2 diabetes case-control cohort comprising 3,093 French Caucasian subjects.RESULTS—IGF2BP2 variants rs4402960 and rs1470579 were not associated with type 2 diabetes in the present study (P = 0.632 and P = 0.896, respectively). Meta-analysis of genotype data from over 34,000 subjects demonstrated that our inability to replicate rs4402960/rs1470579 was consistent with the findings from several previous genome-wide association study (GWAS) datasets that were underpowered to detect this modest association signal (odds ratio [OR] 1.14). We obtained novel evidence that rs9826022, a borderline rare variant (5% minor allele frequency) in the 3′ downstream region, was associated with type 2 diabetes (P = 0.0002; OR 1.53 [95% CI 1.22–1.91]). This result was corroborated by the meta-analysis of 10,542 genotypes from the current study and GWAS datasets using both fixed (P = 9.47 × 10⁻⁶; 1.30 [1.16–1.46]) and random effects (P = 0.001; 1.30 [1.11–1.52)] calculations.CONCLUSIONS—We were unable to replicate the confirmed rs4402960/rs1470579 susceptibility variants but found novel evidence for a rare variant in the 3′ downstream region of IGF2BP2. Further genetic and functional studies are required to identify the etiological IGF2BP2 variants.The insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) gene on chromosome 3q27 is a paralog of IGF2BP1, a known regulator of IGF2 gene expression. Genome-wide association studies (GWASs) carried out by the Finland-U.S. Investigation of NIDDM Genetics (FUSION) (1), the Wellcome Trust Case Control Consortium (WTCCC) (2), and the Diabetes Genetics Initiative (DGI) (3) groups each found modest evidence that single nucleotide polymorphisms (SNPs) in the IGF2BP2 region are associated with type 2 diabetes. The subsequent meta-analysis of primary and replication datasets from these GWASs corroborated these findings and identified two strongly correlated IGF2BP2 variants, rs1470579 and rs4402960, as “confirmed” type 2 diabetes susceptibility variants (1–3). By contrast, the French/Canadian GWAS (4) typed 10 SNPs across the IGF2BP2 locus, including rs1470579, in 1,363 subjects, but found no nominal (P < 0.05) association signals at IGF2BP2. In an attempt to replicate the IGF2BP2 association findings in the French Caucasian population in a larger study and to further characterize the susceptibility variants at this novel locus, we performed an association study of HapMap Phase II tag SNPs spanning the IGF2BP2 locus in 3,093 French Caucasian subjects.     

Role of spinal cyclooxygenase-2 and prostaglandin E2 in fentanyl-induced hyperalgesia in rats

Background

Accumulated evidence suggests that spinal cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2) may be implicated in the development of opioid-induced hyperalgesia.

c-erbB-2和cox-2在乳腺癌中的表达及其意义

应用免疫组化技术 ,检测人乳腺良恶性疾病组织中c erbB 2和cox 2蛋白的表达 ,分析其与淋巴结转移、激素受体状态的关系。 40例乳腺癌组织中c erbB 2表达阳性率为 3 5 .0 %,淋巴结阳性及激素受体阴性者表达率显著高于无淋巴结转移及受体阳性者 (均P <0 .0 5 ) ;cox 2表达阳性率为 47.5 %,激素受体阴性者表达率显著高于受体阳性者 (P <0 .0 5 ) ,但与淋巴结转移无关 (P >0 .0 5 )。 10例良性乳腺疾病及 2例正常乳腺组织中无c erbB 2表达 ,仅有 1例乳腺囊肿病cox 2表达阳性 ,c erbB 2与cox 2的表达存在显著的相关性 (P <0 .0 5 )。提示c erbB 2和cox 2与乳腺癌的发生、转移及预后均有密切关系 ,同时进行两者的免疫组化检测对评估乳腺癌的预后及选择靶向治疗对象可能有意义。     

Circulating level of alpha2-macroglobulin-beta2-microglobulin complex in hemodialysis patients

BACKGROUND: The presence of alpha2-macroglobulin (alpha2M) in amyloid tissue from patients with dialysis-related amyloidosis (DRA) was demonstrated by Argilés et al in 1989. Thereafter, the formation of the complex of beta2-microglobulin (beta2m) with alpha2m was confirmed directly by in vitro study. In Alzheimer's disease, complex formation of amyloid beta-peptide and alpha2M is considered to play an important role in the pathogenesis by modifying the degradation processes of amyloid protein. Thus, we hypothesized that the alpha2M-beta2m complex is an important factor in the pathogenesis of DRA as well. Here, we measured the circulating levels of alpha2M-beta2m complex in the maintenance hemodialysis patients and discussed about its clinical significance in DRA. METHODS: One hundred and thirty-seven hemodialysis patients and 11 prehemodialysis chronic renal failure (CRF) patients were included in this study. The affinity of purified alpha2M for beta2m was confirmed by a highly sensitive 27 MHz quartz crystal microbalance (QCM). The presence of circulating alpha2M-beta2m complex was analyzed by immunoblotting analysis. Furthermore, the serum levels of alpha2M-beta2m complex were measured by sandwich enzyme immunoassay. RESULTS: QCM analysis revealed the high affinity of alpha2M for beta2m. The presence of circulating alpha2M-beta2m complex was detected in two out of a total 11 prehemodialysis CRF patients and in 95 out of the total of 137 hemodialysis patients. None of the healthy subjects, however, were observed to present with any alpha2M-beta2m complex. Serum levels of the alpha2M-beta2m complex were correlated to the duration of hemodialysis (P= 0.043). Serum levels of the alpha2M-beta2m complex were significantly higher in patients with high DRA score than in patients with negative DRA score (P= 0.018). Moreover, serum levels of the alpha2M-beta2m complex showed significantly lower in the hemodiafiltration patients compared to the hemodialysis patients (P= 0.002) and showed a strong correlation with DRA score in hemodialysis patients excluding 11 hemodiafiltration patients (P= 0.0004). CONCLUSION: This study is the first to demonstrate the presence of circulating alpha2M-beta2m complex in hemodialysis patients. Furthermore, we observed the correlation between serum levels of alpha2M-beta2m complex and clinical characteristics of DRA. Thus we concluded that a formation of an alpha2M-beta2m complex may be implicated in DRA.     

P2Y2 receptors and GRK2 are involved in oscillatory fluid flow induced ERK1/2 responses in chondrocytes

Mechanical loading is an important factor regulating cartilage metabolism maintained by chondrocytes. However, some of its underlying mechanisms remain poorly understood. In this study, we employed a chondrogenic cell line ATDC5 to investigate roles of P2Y₂ and GRK2 in chondrocyte mechanotransduction. We first confirmed the expression of chondrocyte markers in differentiated ATDC5 cells. We then exposed both differentiated and undifferentiated ATDC5 cells to oscillatory fluid flow, and found that differentiated ATDC5 cells responded to oscillatory fluid flow by increasing COX‐2 and aggrecan expressions. More importantly, fluid flow induced ERK1/2 response in differentiated cells was increased more than 10 times compared to those in undifferentiated cells. Furthermore, we found that P2Y₂ mRNA and protein levels in differentiated ATDC5 cells were significantly higher than those in undifferentiated cells. In contrast, GRK2 protein levels in differentiated cells were significantly lower than those in undifferentiated cells. Finally, overexpressions of P2Y₂ and GRK2 in differentiated ATDC5 cells result in a 34% increase and a 21% decrease of the ERK1/2 phosphorylation, respectively, in response to oscillatory fluid flow, suggesting important roles of P2Y₂ and GRK2 in chondrocyte mechanotransduction. © 2010 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:828–833     

NRF2与MRP2在原发性胆囊癌中的表达

Objective To detect the expressions of Nuclear factor-erythroid 2 p45-related factor 2 (NRF2) and multidrug resistance-associated protein 2 (MRP2), and investigate their significance in primary gallbladder carcinoma. Methods Immunohistochemistry SP assay and image analysis were used to detect the expressions of NRF2 and MRP2 protein in 59 patients with primary gallbladder carcinoma. Results A highly positive expression rates of NRF2 and MRP2 were found (76.3% and 74. 6%, respectively) in primary gallbladder carcinoma. The expressions of NRF2 and MRP2 had a significantly correlation with metastases, Nevin staging, and differentiation (P＜0.05), but there was no statistical association with sex and age. The expression of NRF2 had a positive correlation with MRP2 (r=0. 589,P＜0.05). Conclusion Both NRF2 and MRP2 were overexpressed in primary gallbladder carcinoma and they may play a role in the development of primary gallbladder carcinoma.