Objective C1q/TNF-related protein(CTRP)1 was initiallyidentified as a paralog of adiponectin based on the similarity in C1q domain of these two proteins.Previously,we showed that CTRP1promotes the development of ather...Objective C1q/TNF-related protein(CTRP)1 was initiallyidentified as a paralog of adiponectin based on the similarity in C1q domain of these two proteins.Previously,we showed that CTRP1promotes the development of atherosclerosis by increasing endothelial adhesiveness.Here,we sought to investigate whether CTRP1 also influences vascular dilatory functions.展开更多
Aim Inducible nitric oxide synthase （iNOS） makes a great contribution to host defense and inflamma-tion. In many settings, lipopolysaccharide （LPS） induces iNOS expression through activation of the inhibitor of K...Aim Inducible nitric oxide synthase （iNOS） makes a great contribution to host defense and inflamma-tion. In many settings, lipopolysaccharide （LPS） induces iNOS expression through activation of the inhibitor of KB- α （IKB-α） -nuclear factor-KB （NF-KB） cascade, whereas interferon-γ （IFN-γ） acts through Janus kinase （ JAK）- signal transducer and activator of transcription 1 （ STAT1 ） signals. Heat shock factor 1 （ HSF1 ）, a major regulator of heat shock protein transcription, has been shown to regulate the production of pro-inflammatory cytokines such as tumor necrosis factor-α（TNF-α） and interleukin-6 （IL-6）. But it remains obscure whether and how HSF1 affects iNOS induction. Methods Western blot was used to measure the protein expression. The mRNA level was meas- ured by real time-PCR. Silence of HSF1 was achieved by small interfering RNA. Nitric oxide （NO） content and NF-KB binding activity were assayed by commercial kits. Chromatin immunoprecipitation （CHIP） was used to measure the binding activity of NF-KB and STAT1 to iNOS promoters. Results HSF1 inhibition or knockdown pre- vented the LPS- and/or IFN-γ-stimulated iNOS protein expression in cultured microglia. HSF1 inhibition blocked iNOS mRNA transcription. These inhibitory effects of HSF1 inhibition on iNOS expression were confirmed in brain tissues from endotoxemic mice. Further analysis showed that HSF1 inhibition had no effect on IKB-α degradation and NF-KB or STAT1 phosphorylation in LPS/IFN-γ-stimulated cells. The nuclear transport of active NF-KB or STAT1 was also not affected by HSF1 inhibition. But HSF1 inhibition reduced the binding of NF-KB and STAT1 to their DNA elements. In addition, HSF1 inhibition reduced NF-KB and STAT1 bindings to iNOS promoter inside the LPS/IFN-γ-stimulated cells. Conclusions This preventing effect of HSF1 inhibition on iNOS mRNA transcription presents the necessary role of HSF1 in iNOS induction.展开更多
目的:观察七龙天对低氧性肺动脉高压(HPH)大鼠内皮素-1(ET-1)、血管内皮细胞一氧化氮合成酶(NOS)的影响。方法:雄性SD大鼠随机分为6组:空白对照组(A)、模型组(B)、波生坦组(C)、七龙天低剂量组(D)、七龙天中剂量组(E)、七龙天高剂量组(F...目的:观察七龙天对低氧性肺动脉高压(HPH)大鼠内皮素-1(ET-1)、血管内皮细胞一氧化氮合成酶(NOS)的影响。方法:雄性SD大鼠随机分为6组:空白对照组(A)、模型组(B)、波生坦组(C)、七龙天低剂量组(D)、七龙天中剂量组(E)、七龙天高剂量组(F)。A组大鼠置于正常环境中饲养,B、C、D、E、F组均造模。采用常压低氧法制模,从制模第1天始给药,连续3周,A、B两组均给予蒸馏水3 m L/(只·d)。在直视下行右心导管术测定肺血流动力学参数,及RT-PCR法检测肺组织中NOS、ET-1 mRNA表达。结果:七龙天及波生坦均可明显降低大鼠肺动脉高压,且以七龙天高剂量组效果为佳,疗效呈药物剂量依赖表现。各组NOS、ET-1表达量与肺动脉压具有相关性,但二者在高剂量七龙天调节至正常范围时,肺动脉压仍未恢复正常水平。结论:不同剂量七龙天均可降低肺动脉高压,且高剂量七龙天疗效优于波生坦。其降压机制与降低NOS及ET-1表达量有关,但仍可能受其他炎症因子及血管新生因子影响。展开更多
文摘Objective C1q/TNF-related protein(CTRP)1 was initiallyidentified as a paralog of adiponectin based on the similarity in C1q domain of these two proteins.Previously,we showed that CTRP1promotes the development of atherosclerosis by increasing endothelial adhesiveness.Here,we sought to investigate whether CTRP1 also influences vascular dilatory functions.
文摘Aim Inducible nitric oxide synthase （iNOS） makes a great contribution to host defense and inflamma-tion. In many settings, lipopolysaccharide （LPS） induces iNOS expression through activation of the inhibitor of KB- α （IKB-α） -nuclear factor-KB （NF-KB） cascade, whereas interferon-γ （IFN-γ） acts through Janus kinase （ JAK）- signal transducer and activator of transcription 1 （ STAT1 ） signals. Heat shock factor 1 （ HSF1 ）, a major regulator of heat shock protein transcription, has been shown to regulate the production of pro-inflammatory cytokines such as tumor necrosis factor-α（TNF-α） and interleukin-6 （IL-6）. But it remains obscure whether and how HSF1 affects iNOS induction. Methods Western blot was used to measure the protein expression. The mRNA level was meas- ured by real time-PCR. Silence of HSF1 was achieved by small interfering RNA. Nitric oxide （NO） content and NF-KB binding activity were assayed by commercial kits. Chromatin immunoprecipitation （CHIP） was used to measure the binding activity of NF-KB and STAT1 to iNOS promoters. Results HSF1 inhibition or knockdown pre- vented the LPS- and/or IFN-γ-stimulated iNOS protein expression in cultured microglia. HSF1 inhibition blocked iNOS mRNA transcription. These inhibitory effects of HSF1 inhibition on iNOS expression were confirmed in brain tissues from endotoxemic mice. Further analysis showed that HSF1 inhibition had no effect on IKB-α degradation and NF-KB or STAT1 phosphorylation in LPS/IFN-γ-stimulated cells. The nuclear transport of active NF-KB or STAT1 was also not affected by HSF1 inhibition. But HSF1 inhibition reduced the binding of NF-KB and STAT1 to their DNA elements. In addition, HSF1 inhibition reduced NF-KB and STAT1 bindings to iNOS promoter inside the LPS/IFN-γ-stimulated cells. Conclusions This preventing effect of HSF1 inhibition on iNOS mRNA transcription presents the necessary role of HSF1 in iNOS induction.
文摘目的观察外源性脂联素对内皮素(ET)1诱导的肝星状细胞(HSC)-T6收缩的影响,探讨脂联素在此过程中的可能作用机制。方法应用胶原晶格法观察不同浓度(0.25、0.5μg/ml)脂联素及脂联素(0.5μg/ml)与左旋硝基精氨酸甲酯(LNAME)(5 mmol/L)共同作用下对ET-1诱导的HSC-T6细胞收缩的影响;分别采用实时荧光定量PCR、Western Blot检测脂联素(0.5μg/ml)作用后HSC-T6细胞中ET-1 mRNA及蛋白的表达,采用ELISA检测脂联素(0.5μg/ml)作用后HSC-T6细胞培养液中ET-1蛋白的表达;采用实时荧光定量PCR及Western Blot检测不同浓度(0.5、1、2μg/ml)脂联素与ET-1共同作用下HSC-T6细胞中诱导型一氧化氮合酶(i NOS)的mRNA及蛋白的表达,同时检测HSC-T6细胞中AMPK、p-AMPK、Akt、p-Akt蛋白的表达。计量资料多组间比较采用方差分析,进一步两两比较采用Dunnett法。结果 (1)胶原晶格实验显示,与空白对照组相比,ET-1组凝胶面积显著收缩[(24.8±7.3)%vs(71.9±4.1)%,P<0.01];脂联素(0.5μg/ml)处理后,明显抑制ET-1引起的收缩[(52.7±20.6)%vs(24.8±7.3)%,P<0.05];L-NAME(5 mmol/L)可以部分抵消脂联素的抑制作用(P>0.05)。(2)脂联素(0.5μg/ml)可以抑制HSC-T6细胞中ET-1 mRNA及蛋白的表达(P<0.05),同时可以抑制细胞上清液中ET-1的蛋白表达,在脂联素的基础上加入L-NAME后,脂联素的上述抑制作用均得到部分逆转。(3)HSC-T6细胞中有i NOS mRNA表达,加入ET-1后i NOS mRNA表达量明显下降(P<0.01),同时加入ET-1和脂联素作用后i NOS mRNA表达较ET-1组增加,且随着脂联素浓度升高i NOS mRNA表达量有逐渐升高的趋势,HSC-T6细胞中i NOS蛋白表达与mRNA表达趋势一致;ET-1处理24 h后HSC-T6细胞中p-AMPK表达水平明显减低,在此基础上加入脂联素后,p-AMPK表达水平明显上升,且随脂联素浓度的增加逐渐增加;ET-1处理24 h后HSC-T6细胞中p-Akt表达水平明显上升,在此基础上加入脂联素后,p-Akt的表达水平下降,且随脂联素浓度的增加逐渐降低。结论脂联素能够抑制ET-1诱导的HSC收缩,其机制可能是通过激活AMPK,增加NO的合成,减少ET-1的合成分泌,同时阻断Akt信号通路来实现的。脂联素抑制HSC的收缩作用可能是其抗肝纤维化的机制之一。
文摘目的:观察七龙天对低氧性肺动脉高压(HPH)大鼠内皮素-1(ET-1)、血管内皮细胞一氧化氮合成酶(NOS)的影响。方法:雄性SD大鼠随机分为6组:空白对照组(A)、模型组(B)、波生坦组(C)、七龙天低剂量组(D)、七龙天中剂量组(E)、七龙天高剂量组(F)。A组大鼠置于正常环境中饲养,B、C、D、E、F组均造模。采用常压低氧法制模,从制模第1天始给药,连续3周,A、B两组均给予蒸馏水3 m L/(只·d)。在直视下行右心导管术测定肺血流动力学参数,及RT-PCR法检测肺组织中NOS、ET-1 mRNA表达。结果:七龙天及波生坦均可明显降低大鼠肺动脉高压,且以七龙天高剂量组效果为佳,疗效呈药物剂量依赖表现。各组NOS、ET-1表达量与肺动脉压具有相关性,但二者在高剂量七龙天调节至正常范围时,肺动脉压仍未恢复正常水平。结论:不同剂量七龙天均可降低肺动脉高压,且高剂量七龙天疗效优于波生坦。其降压机制与降低NOS及ET-1表达量有关,但仍可能受其他炎症因子及血管新生因子影响。
