目的研究益气活血复方对脂多糖(LPS)诱导的人脐静脉内皮细胞(HUVECs)Toll样受体4(TLR4)及其下游信号转导通路元件髓样分化因子88(MyD88)、肿瘤坏死因子受体相关因子-6(TRAF-6)、Toll样受体相关分子(TRAM)、Toll样受体相关的干扰素活化子...目的研究益气活血复方对脂多糖(LPS)诱导的人脐静脉内皮细胞(HUVECs)Toll样受体4(TLR4)及其下游信号转导通路元件髓样分化因子88(MyD88)、肿瘤坏死因子受体相关因子-6(TRAF-6)、Toll样受体相关分子(TRAM)、Toll样受体相关的干扰素活化子(TRIF)表达的影响,探讨益气活血复方含药血清防治动脉粥样硬化(AS)的机制。方法选择新西兰大耳白兔20只,随机分为4组,即正常组、中药高浓度组、中药中浓度组、中药低浓度组,每组5只。以上各组白兔分别以生理盐水和高、中、低浓度益气活血复方连续灌胃7d。末次灌胃给药2h后,心脏采血,离心后分离血清。体外培养人脐静脉内皮细胞,用LPS刺激后,分别加入高、中、低浓度益气活血复方含药血清干预24h,收集细胞,用Real ti me PCR方法测定TLR4、MyD88、TRAF-6、TRAM及TRIF mRNA的表达。结果用LPS刺激人脐静脉内皮细胞后,引起TLR4、MyD88、TRAF-6、TRAM及TRIF mRNA的高表达(与空白对照组比较,P<0.01),用益气活血复方含药血清干预以后显著抑制TLR4、MyD88及TRAF-6 mRNA的高表达(与模型组比较P<0.05或P<0.01),对TRAM及TRIF作用不明显。结论益气活血复方可阻断TLR4高表达,同时阻断TLR4胞内信号转导的MyD88依赖性途径,而对MyD88非依赖性途径作用不明显,因此益气活血复方主要是通过阻断MyD88依赖性途径来发挥其抗动脉粥样硬化的作用。展开更多
目的观察桑黄多糖(polysaccharide from Phellinus igniarius,PPI)对人Toll-样受体4(Toll like receptor 4,TLR4)通路的激活作用及作用特点。方法采用转染了人TLR4基因、分泌型胚胎碱性磷酸酶报告基因的HEK-Blue^(TM)hTLR4细胞模型,快...目的观察桑黄多糖(polysaccharide from Phellinus igniarius,PPI)对人Toll-样受体4(Toll like receptor 4,TLR4)通路的激活作用及作用特点。方法采用转染了人TLR4基因、分泌型胚胎碱性磷酸酶报告基因的HEK-Blue^(TM)hTLR4细胞模型,快速评价PPI对TLR4通路的激活作用,并用PMA诱导的THP-1细胞模型观察药物对TLR4通路作用的特点;MTT法检测细胞活性;ELISA法检测细胞因子分泌量;RealtimePCR检测细胞mRNA表达水平。结果 PPI作用24h不影响细胞活性,但能剂量依赖性地增加HEK-Blue^(TM) hTLR4细胞分泌型胚胎碱性磷酸酶的表达,并使THP-1细胞TLR4通路相关细胞因子TNF-α,IP-10分泌量增加。TLR4受体阻断剂TAK-242能显著降低PPI诱导的细胞因子分泌量(P<0.01)。Real-time PCR结果显示PPI既可以增加MyD88通路TNF-α、IL-6、IL-12、IL-1β、COX-2等细胞因子的mRNA表达,又可以增加TRIF通路IP-10、IFN-β等细胞因子的mRNA表达。结论 PPI对人TLR4受体具有直接激活作用,能同时激活TLR4下游MyD88和TRIF 2条分支,对TLR4分支通路的激活没有选择性。展开更多
Toll-like receptors （TLRs） are sentinels of the host defense system, which recognize a large number of microbial pathogens. The host defense system may be inefficient or inflammatory diseases may develop if microbia...Toll-like receptors （TLRs） are sentinels of the host defense system, which recognize a large number of microbial pathogens. The host defense system may be inefficient or inflammatory diseases may develop if microbial recognition by TLRs and subsequent TLR-triggered cytokine production are deregulated. Activating transcription factor 4 （ATF4）, a member of the ATF/CREB transcription factor family, is an important factor that participates in several pathophysiological processes. In this report, we found that ATF4 is also involved in the TLR-mediated innate immune response, which participates in TLR4 signal transduction and mediates the secretion of a variety of cytokines. We observed that ATF4 is activated and translocates to the nucleus following l ipopolysaccharide （LPS） stimulation via the TLR4-MyD88-dependent pathway. Additionally, a cytokine array assay showed that some key inflammatory cytokines, such as I L-6, I L-8 and RANTES, are positively regulated by ATF4. We also demonstrate that c-Jun directly binds to ATF4, thereby promoting the secretion of inflammatory cytokines. Taken together, these results indicate that ATF4 acts as a positive regulator in TLR4-triggered cytokine production.展开更多
In the present study, we investigated anti-inflammatory effect of Cardamine komarovii flower(CKF) on lipopolysaccharide(LPS)-induced acute lung injury(ALI). We determined the effect of CKF methanolic extracts on LPS-i...In the present study, we investigated anti-inflammatory effect of Cardamine komarovii flower(CKF) on lipopolysaccharide(LPS)-induced acute lung injury(ALI). We determined the effect of CKF methanolic extracts on LPS-induced pro-inflammatory mediators NO and prostaglandin E2(PGE2), production of pro-inflammatory cytokines(IL-1β, TNF-α, and IL-6), and related protein expression levels of MyD88/TRIF signaling pathways in peritoneal macrophages(PMs). Nuclear translocation of NF-κB-p65 was analyzed by immunofluorescence. For the in vivo experiments, an ALI model was established to detect the number of inflammatory cells and inflammatory factors(IL-1β, TNF-α, and IL-6) in bronchoalveolar lavage fluid(BALF) of mice. The pathological damage in lung tissues was evaluated through H&E staining. Our results showed that CKF can decrease the production of inflammatory mediators, such as NO and PGE2, by inhibiting their synthesis-related enzymes i NOS and COX-2 in LPS-induced PMs. In addition, CKF can downregulate the mRNA levels of IL-1β, TNF-α, and IL-6 to inhibit the production of inflammatory factors. Mechanism studies indicated that CKF possesses a fine anti-inflammatory effect by regulating My D88/TRIF dependent signaling pathways. Immunocytochemistry staining showed that the CKF extract attenuates the LPS-induced translocation of NF-kB p65 subunit in the nucleus from the cytoplasm. In vivo experiments revealed that the number of inflammatory cells and IL-1β in BALF of mice decrease after CKF treatment. Histopathological observation of lung tissues showed that CKF can remarkably improve alveolar clearance and infiltration of interstitial and alveolar cells after LPS stimulation. In conclusion, our results suggest that CKF inhibits LPS-induced inflammatory response by inhibiting the MyD88/TRIF signaling pathways, thereby protecting mice from LPS-induced ALI.展开更多
目的 :研究肝细胞肝癌(hepatocellular carcinoma,HCC)中Toll样受体3(Toll-like receptor 3,TLR3)及信号分子含TIR结构域的转接蛋白(TIR-domain-containing adaptor protein including IFN-β,TRIF)表达与细胞自噬相关蛋白Beclin1和LC3...目的 :研究肝细胞肝癌(hepatocellular carcinoma,HCC)中Toll样受体3(Toll-like receptor 3,TLR3)及信号分子含TIR结构域的转接蛋白(TIR-domain-containing adaptor protein including IFN-β,TRIF)表达与细胞自噬相关蛋白Beclin1和LC3表达的相关性及临床意义,并探讨相关机制。方法:收集与随访101例HCC病例,构建肝组织芯片。HE染色判断HCC的组织分化,免疫组化染色检测HCC组织中Ki-67、TLR3、TRIF、LC3和Beclin l的表达,应用TUNEL方法检测肿瘤细胞凋亡信号。统计学分析其临床病理因素和预后。结果:本组HCC中TLR3和TRIF表达呈正相关(ρ=0.640,P<0.001),其高表达分别与肿瘤Hbs Ag感染、硬化背景、细胞凋亡指数(apoptosis index,AI)及患者5年总生存率呈正相关,与肿瘤细胞增殖、血管浸润、Edmondson分级和TNM分期呈负相关。Beclin1和LC3表达呈显著正相关(ρ=0.587,P<0.001),两者高表达分别与肿瘤脉管浸润、Edmondson分级、TNM分期、肿瘤细胞增殖呈正相关,与AI和预后呈负相关。并且TLR3、TRIF分别与LC3和Beclin1的表达呈负相关(P均<0.001)。结论:HCC中TLR3及其信号分子TRIF表达,细胞自噬相关基因Beclin1和LC3的表达分别通过调控细胞增殖、凋亡和自噬来影响肿瘤的生物学行为和预后。HCC组织中Beclin1介导的自噬途径与TLR3信号凋亡通路存在交叉,两条通路异常可能是HCC发生、进展的机制之一。展开更多
文摘目的研究益气活血复方对脂多糖(LPS)诱导的人脐静脉内皮细胞(HUVECs)Toll样受体4(TLR4)及其下游信号转导通路元件髓样分化因子88(MyD88)、肿瘤坏死因子受体相关因子-6(TRAF-6)、Toll样受体相关分子(TRAM)、Toll样受体相关的干扰素活化子(TRIF)表达的影响,探讨益气活血复方含药血清防治动脉粥样硬化(AS)的机制。方法选择新西兰大耳白兔20只,随机分为4组,即正常组、中药高浓度组、中药中浓度组、中药低浓度组,每组5只。以上各组白兔分别以生理盐水和高、中、低浓度益气活血复方连续灌胃7d。末次灌胃给药2h后,心脏采血,离心后分离血清。体外培养人脐静脉内皮细胞,用LPS刺激后,分别加入高、中、低浓度益气活血复方含药血清干预24h,收集细胞,用Real ti me PCR方法测定TLR4、MyD88、TRAF-6、TRAM及TRIF mRNA的表达。结果用LPS刺激人脐静脉内皮细胞后,引起TLR4、MyD88、TRAF-6、TRAM及TRIF mRNA的高表达(与空白对照组比较,P<0.01),用益气活血复方含药血清干预以后显著抑制TLR4、MyD88及TRAF-6 mRNA的高表达(与模型组比较P<0.05或P<0.01),对TRAM及TRIF作用不明显。结论益气活血复方可阻断TLR4高表达,同时阻断TLR4胞内信号转导的MyD88依赖性途径,而对MyD88非依赖性途径作用不明显,因此益气活血复方主要是通过阻断MyD88依赖性途径来发挥其抗动脉粥样硬化的作用。
文摘Toll-like receptors （TLRs） are sentinels of the host defense system, which recognize a large number of microbial pathogens. The host defense system may be inefficient or inflammatory diseases may develop if microbial recognition by TLRs and subsequent TLR-triggered cytokine production are deregulated. Activating transcription factor 4 （ATF4）, a member of the ATF/CREB transcription factor family, is an important factor that participates in several pathophysiological processes. In this report, we found that ATF4 is also involved in the TLR-mediated innate immune response, which participates in TLR4 signal transduction and mediates the secretion of a variety of cytokines. We observed that ATF4 is activated and translocates to the nucleus following l ipopolysaccharide （LPS） stimulation via the TLR4-MyD88-dependent pathway. Additionally, a cytokine array assay showed that some key inflammatory cytokines, such as I L-6, I L-8 and RANTES, are positively regulated by ATF4. We also demonstrate that c-Jun directly binds to ATF4, thereby promoting the secretion of inflammatory cytokines. Taken together, these results indicate that ATF4 acts as a positive regulator in TLR4-triggered cytokine production.
基金supported by the National Natural Science Foundation of China(Nos.81603365,81860741 and 81760763)
文摘In the present study, we investigated anti-inflammatory effect of Cardamine komarovii flower(CKF) on lipopolysaccharide(LPS)-induced acute lung injury(ALI). We determined the effect of CKF methanolic extracts on LPS-induced pro-inflammatory mediators NO and prostaglandin E2(PGE2), production of pro-inflammatory cytokines(IL-1β, TNF-α, and IL-6), and related protein expression levels of MyD88/TRIF signaling pathways in peritoneal macrophages(PMs). Nuclear translocation of NF-κB-p65 was analyzed by immunofluorescence. For the in vivo experiments, an ALI model was established to detect the number of inflammatory cells and inflammatory factors(IL-1β, TNF-α, and IL-6) in bronchoalveolar lavage fluid(BALF) of mice. The pathological damage in lung tissues was evaluated through H&E staining. Our results showed that CKF can decrease the production of inflammatory mediators, such as NO and PGE2, by inhibiting their synthesis-related enzymes i NOS and COX-2 in LPS-induced PMs. In addition, CKF can downregulate the mRNA levels of IL-1β, TNF-α, and IL-6 to inhibit the production of inflammatory factors. Mechanism studies indicated that CKF possesses a fine anti-inflammatory effect by regulating My D88/TRIF dependent signaling pathways. Immunocytochemistry staining showed that the CKF extract attenuates the LPS-induced translocation of NF-kB p65 subunit in the nucleus from the cytoplasm. In vivo experiments revealed that the number of inflammatory cells and IL-1β in BALF of mice decrease after CKF treatment. Histopathological observation of lung tissues showed that CKF can remarkably improve alveolar clearance and infiltration of interstitial and alveolar cells after LPS stimulation. In conclusion, our results suggest that CKF inhibits LPS-induced inflammatory response by inhibiting the MyD88/TRIF signaling pathways, thereby protecting mice from LPS-induced ALI.
