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31.
连翘酯苷对内毒素作用下RAW264.7细胞功能的影响   总被引:1,自引:0,他引:1  
为探讨连翘酯苷(FS)对内毒素(LPS)作用下RAW264.7细胞增殖、分泌NO和TNF-α、吞噬功能的影响。收集处于对数生长期细胞,用含10%胎牛血清的RPMI1640培养细胞,在培养液中分别加入脂多糖(LPS)以及不同浓度40、80、160 μg/mL的FS共培养。采用MTT法检测细胞增殖,Griess和ELISA法分别检测RAW 264.7细胞分泌NO和TNF-α量,染色法检测细胞吞噬能力。结果表明:低、中剂量FS可显著促进细胞增殖,而中和高剂量FS可缓解LPS对细胞的刺激作用;与LPS组比较,FS对LPS刺激的RAW 264.7细胞分泌NO影响不明显,但中、高剂量FS明显促进RAW 264.7细胞分泌;LPS与FS均能提高巨噬细胞吞噬鸡红细胞能力。FS对RAW264.7细胞增殖、分泌NO和TNF-α以及吞噬功能都有影响,结果提示这可能是连翘酯苷调节细胞免疫功能的机制之一。  相似文献   
32.
为了研究邻苯二甲酸二乙基己酯(DEHP)对巨噬细胞的免疫毒性,采用不同浓度剂量DEHP处理小鼠巨噬细胞株RAW264.7细胞和腹腔巨噬细胞,通过检测细胞吞噬、细胞因子分泌及活性氧水平变化探讨DEHP暴露对免疫系统的毒性作用。结果表明:高浓度(20、40、80 mg·L-1)DEHP处理48 h后对RAW264.7细胞可造成急性损伤。低浓度(1、5、10 mg·L-1)DEHP连续染毒处理10代后,RAW264.7细胞吞噬红细胞百分率及吞噬指数显著抑制(P0.05)。RAW264.7细胞分泌TNF-α、IL-12和IL-23等细胞因子能力明显降低,并表现出一定的剂量-效应关系。随着DEHP暴露浓度的增加,DEHP染毒造成RAW264.7细胞内活性氧产生,受损加剧。除此之外,DEHP暴露还能明显抑制小鼠腹腔巨噬细胞对红细胞的吞噬能力(P0.05)。以上结果表明,DEHP暴露对巨噬细胞具有免疫抑制作用,损伤了巨噬细胞正常免疫功能发挥。  相似文献   
33.
本研究旨在解析巨噬细胞RAW264.7在应对细粒棘球绦虫原头蚴刺激时其Th1、Th2型免疫反应相关基因的差异表达规律,为进一步揭示巨噬细胞抗细粒棘球绦虫原头蚴免疫调控机制奠定理论基础.将细粒棘球绦虫原头蚴和巨噬细胞RAW264.7共培养6、24、72 h,收集RAW264.7细胞,提取总RNA,构建cDNA文库,利用R...  相似文献   
34.
研究了太子参须多糖粗提物对RAW264.7巨噬细胞体外增殖及细胞免疫活性的影响,进一步评价了太子参须多糖对隐球菌感染模型小鼠的免疫调理作用.结果表明,太子参须多糖粗提物能显著提高RAW264.7巨噬细胞的相对增殖率,促进巨噬细胞对中性红和隐球菌的吞噬能力;太子参须多糖能恢复隐球菌感染小鼠的体质量,增加IL-10,IL-1β及TNF-α的分泌,降低IL-6的分泌,减少感染小鼠肺部和脑部的隐球菌数量,并增强了肺部TLR4受体、 CREB和p-CREB的表达.因此得出,太子参须多糖能通过提高巨噬细胞的免疫活性调节小鼠免疫功能,从而增强机体的抗炎能力.  相似文献   
35.
5-(1H-吲哚-3-基甲基)-3-甲基-2-硫酮-4-咪唑烷酮(Necrostatin-1,Nec-1)是一种能够特异的、有效抑制细胞程序性凋亡的小分子物质.为了探讨Nec-1对卡介苗(Bacillus Calmette-Guérin,BCG)诱导的小鼠(Mus musculus)巨噬细胞RAW264.7凋亡的调控作用,本研究采用3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐(3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide,MTT)比色法检测细胞存活率,Annexin V和碘化丙啶(propidine iodide,PI)双染法检测细胞凋亡率,JC-1染色法检测细胞线粒体膜电位水平,采用分光光度法检测细胞内Caspase-3的酶活性,qRT-PCR和Westemblot法检测凋亡相关基因的mRNA和蛋白表达水平.结果表明,Nec-1可提高被BCG感染巨噬细胞的存活率,降低其凋亡率,通过降低线粒体膜电位水平、上调抑凋亡基因Bcl-2的表达同时下调RIP1、RIP3和BAX基因的表达水平,从而有效降低了Caspase-3的蛋白表达量及酶活性.本研究表明Nec-1可通过提高线粒体膜电位水平、并下调促凋亡蛋白的表达量,从而抑制被BCG感染后巨噬细胞的凋亡,这将有助于进一步研究结核分枝杆菌(Mycobacterium tuberculosis)与巨噬细胞间的相互作用,对于揭示结核病的致病机理具有重要意义.  相似文献   
36.
Eight sesquiterpene quinones: ilimaquinone (1), smenospongidine (3), smenospongiarine (5), smenospongine (7), and their corresponding 5-epimers 2, 4, 6, and 8, isolated from the Palauan marine sponge Hippospongia sp., were examined regarding their effects on TNF-α production in LPS-stimulated RAW 264.7 cells. 5-Epi-smenospongine (8) promoted the production of TNF-α to a level three times greater than the control at 10 μM, but compounds 17 did not show apparent activity. The results suggest that the cis-decaline ring and a primary amine in the benzoquinone ring are necessary for activity. This is the first study to report the modulation of TNF-α production by a sesquiterpene quinone.  相似文献   
37.
旨在探讨脂肪酸结合蛋白4(fatty acid binding protein,FABP4)在牛分枝杆菌卡介苗(BCG)感染的巨噬细胞中对脂肪酸代谢与自噬的调控作用。本研究利用小干扰RNA技术敲减小鼠巨噬细胞系RAW264.7中FABP4的表达,并结合BCG感染,采用免疫印记和免疫荧光等技术,检测了FABP4蛋白表达、脂肪酸累积、脂肪酸β氧化和自噬相关蛋白表达等指标。结果表明,BCG感染极显著上调了小鼠巨噬细胞RAW264.7中FABP4的表达(P<0.001)并促进了脂肪酸的累积。FABP4小干扰RNA(siRNA-FABP4)能显著降低BCG感染后巨噬细胞中脂肪酸含量,伴随着肉毒碱棕榈酰移位酶1A(CPT1A)的表达上调(P<0.05),与ATP产量的提升(P<0.05)。同时,siRNA-FABP4极显著下调了自噬调控关键因子AMPK及自噬相关蛋白p-ULK1、ATG5、ATG7、ATG12和LC3B的表达(P<0.01)。以上研究结果表明,在BCG感染RAW264.7细胞过程中,下调了FABP4的表达,促进了脂肪酸的氧化,减少了巨噬细胞内脂肪酸的含量,并通过AMPK信号通路抑制了细胞自噬的发生。  相似文献   
38.
巨噬细胞是机体抗吞噬能力最强的细胞,但布鲁氏菌不但不能被巨噬细胞杀死,反而能在胞内大量繁殖,因此,本研究建立其感染模型,为下一步继续研究布鲁氏菌与其宿主细胞表面相关膜蛋白之间的作用和胞内寄生机制奠定基础。用羊布鲁氏菌强毒株16M感染巨噬细胞系264.7(细胞和细菌比例为1∶500),感染时间为4 h,建立布鲁氏菌感染巨噬细胞模型,做间接免疫荧光试验和透射电镜试验。间接免疫荧光试验中一抗与二抗最佳稀释度分别为1∶80和1∶80,电镜下观察到细菌侵入细胞时膜凹陷,形态发生变化,形成内吞小体。本试验减少感染过程所涉及的环境因素,优化了间接免疫荧光试验所需的一抗和二抗浓度比,成功建立感染模型。  相似文献   
39.
AIM:To investigate the function of receptor-interacting proteins 3 (RIP3) in regulating Bacillus Calmette-Guérin (BCG)-induced apoptosis of mouse macrophages (RAW264.7 cells). METHODS:The RIP3 adenovirus interference vector was constructed and used to infect the RAW264.7 cells, and then the RAW264.7 cells were infected with BCG. The cell viability was measured by MTT assay. The apoptotic rate, mitochondrial membrane potential and production of reactive oxygen species (ROS) were determined by flow cytometry analysis. The protein levels of RIP3 and apoptosis-associated proteins were examined by Western blot. RESULTS:The viability of RAW264.7 cells was decreased after BCG infection. In the meantime, the expression of RIP3 was up-regulated significantly (P<0.01). Compared with BCG infection group, the apoptotic rate and ROS level in BCG and RIP3 adenovirus interference vector co-infection group were significantly decreased (P<0.01). Importantly, RIP3 was able to further promote apoptosis in BCG-infected RAW264.7 cells in part by increasing mitochondrial membrane potential (P<0.01). In addition, Western blot analysis further demonstrated that RIP3 was involved in BCG-induced apoptosis partly through down-regulation of anti-apoptotic protein Bcl-2, and up-regulation of Bax and cleaved caspase-3 (P<0.01). CONCLUSION:RIP3 is involved in BCG-induced apoptosis of RAW264.7 cells, and this process may be achieved by the mitochondrial pathway.  相似文献   
40.
Fucosterol is a phytosterol that is abundant in marine brown algae and is a renowned secondary metabolite. However, its ability to protect macrophages against particulate matter (PM) has not been clarified with regard to inflammation; thus, this study aimed to illustrate the above. Padina boryana, a brown algae that is widespread in Indo–Pacific waters, was applied in the isolation of fucosterol. Isolation was conducted using silica open columns, while identification was assisted with gas chromatography-mass spectroscopy (GC-MS) and NMR. Elevated levels of PM led the research objectives toward the implementation of it as a stimulant. Both inflammation and oxidative stress were caused due the fact of its effect. RAW 264.7 macrophages were used as a model system to evaluate the process. It was apparent that the increased NO production levels, due to the PM, were mediated through the inflammatory mediators, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and pro-inflammatory cytokines (i.e., interleukin-6 (IL-6), interleukin-1 (IL-1β) and tumor necrosis factor-α (TNF-α), including prostaglandin E2 (PGE2)). Further, investigations provided solid evidence regarding the involvement of NF-κB and mitogen-activated protein kinases (MAPKs) in the process. Oxidative stress/inflammation which are inseparable components of the cellular homeostasis were intersected through the Nrf2/HO-1 pathway. Conclusively, fucosterol is a potent protector against PM-induced inflammation in macrophages and hence be utilized as natural product secondary metabolite in a sustainable manner.  相似文献   
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