苹果多糖的制备及对脂多糖诱导RAW 264.7细胞凋亡的影响

摘 要 目的：观察苹果多糖（AP）对脂多糖（LPS）诱导RAW 264.7细胞凋亡的影响及其机制。方法: 采用水提醇沉法从苹果果渣中提取苹果多糖,并测定其糖含量和分子量。采用流式细胞仪考察AP对LPS诱导RAW 264.7细胞凋亡的作用。采用Western Blot法考察AP对LPS诱导RAW 264.7细胞中Bcl 2、Bax蛋白表达的影响。结果: 经水提醇沉法提取纯化得到苹果多糖的糖含量为91.3%,重均分子量为184613 Da。流式细胞仪检测结果显示,LPS诱导RAW 264.7细胞凋亡明显高于正常对照组（P<0.01）;与LPS组比较,浓度为0.5 mg·mL^-1的AP作用72 h后RAW 264.7细胞凋亡率显著降低（P<0.01）,浓度为1.0 mg·mL^-1的AP作用48,72 h后RAW 264.7细胞凋亡率显著降低（P<0.01）。Western Blot检测结果显示,与正常对照组比较,LPS诱导RAW 264.7细胞中的Bcl 2蛋白在48,72 h表达明显升高,差异具有统计学意义（P<0.01）;与LPS组比较,浓度为1 mg·mL^-1的AP作用后,升高了LPS诱导的RAW 264.7细胞Bcl 2蛋白的表达,降低其Bax蛋白的表达,差异具有统计学意义（P<0.01）。结论:AP抑制LPS诱导RAW 264.7细胞凋亡,其机制可能是通过提高RAW 264.7细胞中Bcl 2蛋白的表达,降低其Bax蛋白表达。     

染料木素MePEG-PLGA共聚物胶束体内外抗肿瘤作用

目的 探讨染料木素MePEG-PLGA共聚物胶束对人肝癌SMMC-7721细胞的体内外抗肿瘤作用。方法 采用MTT法、Annexin V-FITC/PI染法分别考察染料木素MePEG-PLGA共聚物胶束对人肝癌SMMC-7721细胞的细胞毒性、细胞凋亡、细胞周期的影响;通过荷肝SMMC-7721瘤裸鼠体内抗肿瘤试验,考察染料木素胶束的体内抗肿瘤效应。结果 染料木素胶束对肝癌SMMC-7721细胞的抑制率均高于染料木素,最高抑制率分别可达83.26%,78.25%。流式细胞仪检测结果显示,染料木素胶束组能够提高染料木素对SMMC-7721细胞凋亡的诱导能力,并且呈浓度依赖性。5,10,20 μg·mL^-1的染料木素组和染料木素胶束组药物作用于SMMC-7721细胞48 h时,染料木素胶束能够明显提高染料木素对细胞G₂/M期细胞的阻滞作用,并且呈现浓度依赖性。体内抗肿瘤试验结果表明,相同浓度的染料木素胶束组的抑瘤效果显著强于染料木素乳剂组,呈浓度依赖性,最高抑瘤率可达55.41%。结论 染料木素MePEG-PLGA共聚物胶束在体内和体外均有显著的抗肝癌作用。     

染料木素的研究进展

染料木素是从大豆、三叶草、葛根等植物中提取出来的异黄酮化合物,水溶性和脂溶性都较差,它有多种生理学功能。近年来,国内外学者对其提取分离方法、分析方法、药理作用、结构修饰等方面进行了研究。本文简要综述了这一领域近年来的研究进展,以促使对其的研究和应用。     

染料木素通过JNK调控Fas通路的抗Aβ诱导的PC12细胞凋亡机制研究

目的探讨染料木素(genistein,GEN)通过激活JNK调控Fas通路抑制Aβ(25-35)诱导的PC12细胞损伤凋亡的作用及分子机制。方法建立Aβ(25-35)诱导的PC12细胞模型,MTT法和流式细胞仪法测定细胞活力和凋亡率,荧光定量PCR检测Fas凋亡通路相关基因Fas、Fas L、caspase-3和caspase-8 mRNA相对表达情况,分光光度法检测caspase-3和caspase-8酶活性,Western blot检测JNK和pJNK蛋白表达水平变化。结果 GEN下调Aβ(25-35)诱导引起的Fas、Fas L、caspase-3和caspase-8 mRNA水平的增加,抑制Aβ(25-35)诱导的caspase-3和caspase-8酶活性,且明显降低Aβ(25-35)诱导的JNK磷酸化水平。结论GEN通过降低Aβ(25-35)诱导的JNK磷酸化激活,调控JNK依赖的Fas凋亡通路,从而抑制Aβ(25-35)诱导的PC12细胞凋亡,发挥神经保护作用。     

染料木素对人宫颈癌Siha细胞增殖凋亡和周期的影响

［摘要］目的探讨染料木素对人宫颈癌Siha细胞增殖、凋亡和周期的影响及机制。方法50 mol&#8226;mL 1染料木素处理Siha细胞,用噻唑蓝（MTT）法检测细胞生长抑制率,用流式细胞术（FCM）检测细胞凋亡、周期及周期蛋白cyclin A和cyclin B表达的变化。结果染料木素作用于Siha细胞后,增殖抑制率比对照组明显升高（P＜0.05）;染料木素处理48 h后,实验组凋亡率较对照组升高,分别为（67.45±1.54）%和（45.37±1.65）%（P＜0.01）。染料木素处理后的Siha细胞G2/M期的细胞比例显著上升,由（9.55±0.71）%升至（79.54±1.09）%（P＜0.01）;cyclin A和cyclin B表达上调,分别由（1.84±0.11）%升至（37.38±0.71）%（P＜0.01）,由（69.44±1.84）%升至（97.70±1.20）%（P＜0.01）。结论染料木素在体外可有效抑制人宫颈癌细胞生长,其抗肿瘤机制可能是上调cyclin A和cyclin B蛋白表达和引起G2/M期细胞周期阻滞。     

染料木素对脂多糖诱导的人单核细胞与主动脉内皮细胞黏附的影响

目的 探讨染料木素对脂多糖(LPS)同时诱导的人单核细胞(THP-1)与人主动脉内皮细胞(HAEC)黏附的影响作用.方法 分别培养THP-1细胞与HAEC细胞,用不同浓度染料木素预处理两种细胞30 min,然后用LPS同时诱导两种细胞4h,将THP-1细胞加入到HAEC细胞中共培养1h,用孟加拉玫瑰红法检测THP-1细胞与HAEC细胞黏附情况;用酶联免疫吸附法检测细胞培养液上清中血管细胞黏附分子-1(VCAM-1)、细胞间黏附分子-1(ICAM-1)的浓度.结果 LPS能促使THP-1细胞与HAEC细胞黏附,促进VCAM-1和ICAM-1释放;加入染料木素后,两种细胞的黏附量及VCAM-1和ICAM-1的释放呈浓度依赖性减少(P＜0.05).结论 染料木素对脂多糖同时诱导的THP-1细胞与HAEC细胞的黏附有抑制作用.     

染料木素的药代动力学研究

总结了国内外近5年有关染料木素的药代动力学研究资料,从吸收、分布、代谢、排泄四个方面进行归纳分析,以指导临床合理用药。     

染料木素的药理作用

染料木素是一种大豆异黄酮类植物雌激素,本文综述其雌激素样作用、抗肿瘤、抗糖尿病、预防心血管系统疾病等多种药理学效应.     

紫苏叶中2个新木脂素及其对NO合成酶的TNF—α在鼠巨噬细胞RAW264.7中表达的抑制

金丝桃属植物中的许多次生代谢产物都是具生物活性且含酰基间苯三酚的化合物。作者从乌兹别克斯坦常用传统草药糙枝金丝桃 Hypericum scabrum 的地上部分分得9个新的带有多个异戊二烯基侧链的苯甲酰间苯三酚衍生物,拟名为 hyperibone A～I(1～     

Paraquat Induces Apoptosis through a Mitochondria-Dependent Pathway in RAW264.7 Cells

Paraquat dichloride (N,N-dimethyl-4-4′-bipiridinium, PQ) is an extremely toxic chemical that is widely used in herbicides. PQ generates reactive oxygen species (ROS) and causes multiple organ failure. In particular, PQ has been reported to be an immunotoxic agrochemical compound. PQ was shown to decrease the number of macrophages in rats and suppress monocyte phagocytic activity in mice. However, the effect of PQ on macrophage cell viability remains unclear. In this study, we evaluated the cytotoxic effect of PQ on the mouse macrophage cell line, RAW264.7 and its possible mechanism of action. RAW264.7 cells were treated with PQ (0, 75, and 150 μM), and cellular apoptosis, mitochondrial membrane potential (MMP), and intracellular ROS levels were determined. Morphological changes to the cell nucleus and cellular apoptosis were also evaluated by DAPI and Annexin V staining, respectively. In this study, PQ induced apoptotic cell death by dose-dependently decreasing MMP. Additionally, PQ increased the cleaved form of caspase-3, an apoptotic marker. In conclusion, PQ induces apoptosis in RAW264.7 cells through a ROS-mediated mitochondrial pathway. Thus, our study improves our knowledge of PQ-induced toxicity, and may give us a greater understanding of how PQ affects the immune system.     

Functional components in Scutellaria barbata D. Don with anti-inflammatory activity on RAW 264.7 cells

The objectives of this study were to determine the variety and amount of various functional components in Scutellaria barbata D. Don as well as study their anti-inflammatory activity on RAW 264.7 cells. Both ethanol and ethyl acetate extracts were shown to contain the functional components including phenolics, flavonoids, chlorophylls, and carotenoids, with the former mainly composed of phenolics and flavonoids, and the latter of carotenoids and chlorophylls. Both extracts could significantly inhibit (p < 0.05) the production of lipopolysaccharide-induced nitric oxide, prostaglandin E₂, interlukin-6, and interlukin-1β, as well as the expressions of phosphor extracellular signal-regulated kinase and phosphor-c-Jun N-terminal kinase (p-JNK), but failed to retard tumor necrosis factor-α expression. Both ethanol and ethyl acetate extracts had a dose-dependent anti-inflammatory activity on RAW 264.7 cells. Furthermore, the anti-inflammatory efficiency can be varied for both ethanol and ethyl acetate extracts, which can be attributed to the presence of different varieties and amounts of functional components, as mentioned above. This finding suggested that S. Barbata extract may be used as an anti-inflammatory agent for possible future biomedical application.     

Genistein induces activation of the mitochondrial apoptosis pathway by inhibiting phosphorylation of Akt in colorectal cancer cells

Context: Genistein inhibits the proliferation and induces apoptosis of colorectal cancer cells; however, the underling molecular mechanisms remain to be determined.

Aim: The aim of this study was to investigate whether genistein reduces cell viability by suppressing the phosphorylation of AKT and activating the mitochondrial apoptosis pathway in colorectal cancer cells.

Materials and methods: The anti-proliferative effects of genistein (0, 25, 50, and 100?μM) on HCT-116 and LoVo cells were assessed using MTT assay. Genistein-induced apoptosis was measured by Hoechst 33258 staining and flow cytometry. The mRNA level of Bax was detected by real-time PCR. The protein levels of Bax, total Akt, and phosphorylated Akt were assessed by western blot.

Results: The IC₅₀ values of genistein were 690, 135, and 61?μM in HCT-116 cells and 204, 135, and 93?μM in LoVo cells after treatment for 24, 48, and 72?h, respectively. After treatment with different concentrations of genistein (0, 25, 50, and 100?μM) for 48?h, the early apoptotic cells in HCT-116 increased from 1.99%?±?0.55% to 6.78%?±?2.12%, 23.16%?±?3.87%, and 36.99%?±?3.76%, respectively. The same concentrations of genistein increased the early apoptotic cells in LoVo from 2.56%?±?1.42% to 3.21%?±?1.52%, 18.22%?±?3.56%, and 23.56%?±?3.02%, respectively. Moreover, genistein increased the mRNA and protein levels of Bax, while it inhibited the phosphorylation of Akt in HCT-116 cells.

Conclusion: Genistein inhibited cell proliferation and induced apoptosis of colorectal cancer cells. Genistein induced the mitochondrial pathway of apoptosis in HCT-116 cells by inhibiting phosphorylation of Akt.     

cDNA microarray analysis of the gene expression of murine leukemia RAW 264.7 cells after exposure to propofol

Propofol (2,6‐diisopropylphenol) is the most extensively used general anesthetic‐sedative agent and it is employed in clinical patients. It has been shown that propofol exhibits anticancer activities. However, there is no available information to address propofol‐induced cytotoxic effects and affected gene expressions on murine leukemia cells. Therefore, we investigated the effects of propofol on the levels of protein and gene expression, which are associated with apoptotic death in mouse leukemia RAW 264.7 cells in vitro. Results indicated that propofol induced cell morphological changes, cytotoxicity, and induction of apoptosis in RAW 264.7 cells in vitro. Western blot analysis demonstrated that propofol promoted Fas, cytochrome c, caspase‐9 and ?3 active form and Bax levels, but inhibited Bcl‐xl protein level which led to cell apoptosis. Furthermore, cDNA microarray assay indicated that propofol significantly enhanced 5 gene expressions (Gm4884; Gm10883; Lce1c; Lrg1; and LOC100045878) and significantly suppressed 26 gene expressions (Gm10679; Zfp617; LOC621831; LOC621831; Gm5929; Snord116; Gm3994; LOC380994; Gm5592; LOC380994; Gm4638; LOC280487; Gm4638; Tex24; A530064D06Rik; BC094916; EG668725; Gm189; Hist2h3c2; Gm8020; Snord115; Gm3079; Olfr198; Tdh; Snord115; and Olfr1249). Based on these observations, propofol‐altered apoptosis‐related proteins might result from induction of apoptotic gene expression and inhibition of cell growth gene expression, which finally led to apoptosis in a mouse leukemia cell line (RAW 264.7) in vitro. © 2011 Wiley Periodicals, Inc. Environ Toxicol 28: 471–478, 2013.     

芦荟大黄素对LPS诱导的RAW264.7细胞NO生成及iNOS表达的影响

目的观察芦荟大黄素(aloe-emodin)对脂多糖(LPS)诱导的RAW264.7细胞一氧化氮(NO)生成及诱生型一氧化氮合酶(iNOS)mRNA表达的作用。方法采用LPS诱导的RAW264.7细胞株建立细胞炎症反应模型。采用Griess试剂法测定NO释放量;采用硝普钠释放NO法测定NO自由基含量的变化;采用反转录聚合酶链反应(RT-PCR)分析iNOS mRNA表达改变。结果芦荟大黄素在0.69～2.50mg·L-1剂量范围内可抑制LPS诱导的RAW264.7细胞NO的释放,并呈剂量和时间依赖关系;芦荟大黄素在0.63～5.00mg·L-1剂量范围内可下调LPS诱导的RAW264.7细胞iNOS mRNA含量;而此范围内芦荟大黄素无直接清除NO自由基作用,不影响iNOS活性。结论芦荟大黄素可明显降低LPS诱导的RAW264.7细胞NO释放,呈时间和剂量依赖关系,此作用并非通过捕捉NO或抑制iNOS活性来实现,而是通过抑制iNOS mRNA表达发挥作用的。     

人参总皂苷在巨噬细胞RAW264.7中降低脂多糖诱导的炎症和氧化应激

目的:通过脂多糖诱导巨噬细胞RAW264.7建立炎症和氧化应激模型,探讨人参总皂苷的抗炎和抗氧化效果以及对脂多糖诱导的巨噬细胞RAW264.7自噬水平的影响。方法:培养RAW264.7细胞,给予脂多糖刺激并加入不同浓度人参总皂苷,使用硝酸还原酶法检测细胞内一氧化氮水平;ELISA法检测小鼠肿瘤坏死因子α(tumor necrosis factor-α,TNF-α)的分泌;DCFH-DA荧光探针法检测人参总皂苷处理后活性氧的变化;超氧化物阴离子荧光探针(dihydroethidium, DHE)检测细胞内超氧化物阴离子水平;吖啶橙染色法检测自噬体的形成;Western Blot法检测COX-2、NF-кB、Nrf2、HO-1、GCLC、GCLM、Beclin1、ATG7和LC3的蛋白表达。结果:与脂多糖模型组相比,随着TGS的浓度增加,细胞一氧化氮水平、TNF-α的分泌降低,细胞内活性氧和超氧阴离子的含量降低,巨噬细胞RAW264.7酸性自噬体的数量增加;Nrf2、HO-1、GCLC、GCLM、Beclin1、ATG7及LC3的蛋白表达提高,COX-2、NF-кB的蛋白表达降低。结论:在...     

Toll样受体信号途径在RAW264.7细胞川崎病模型炎症反应中的作用及其机制研究

目的探讨Toll样受体(TLR)2信号途径在RAW264.7细胞川崎病模型炎症反应中的作用及其分子机制。方法构建TLR2-干扰小RNA(siRNA),合成2对特异性针对TLR2基因的siRNA序列,并用于转染RAW264.7细胞。实时荧光聚合酶链反应和蛋白质印迹法检测TLR2-siRNA对干酪乳杆菌细胞壁提取物(LCWE)诱导RAW264.7细胞p38促分裂原活化的蛋白激酶(MAPK)、基质多属蛋白酶(MMP)-9表达的影响,乳胶增强免疫比浊定量法检测培养基中高敏C反应蛋白(hsCRP)水平的变化;检测p38MAPK抑制剂SB 203580对LCWE诱导RAW264.7细胞MMP-9表达的影响。结果与对照组相比,LCWE刺激组p-p38MAPK、MMP-9的表达及hs-CRP水平都有明显升高,差异具有统计学意义(P<0.05),与LCWE刺激组相比,TLR2-siRNA+LCWE刺激组的p-p38MAPK、MMP-9表达和hs CRP水平降低,差异具有统计学意义(P<0.05)。与LCWE刺激组相比,SB203580+LCWE刺激组的MMP-9表达减轻,差异具有统计学意义(P<0.05)。结论 TLR2-siRNA可以有效减轻LCWE刺激造成的p-p38MAPK、MMP-9、hs-CRP表达升高。p38MAPK抑制剂SB203580对LCWE诱导RAW264.7细胞MMP-9表达有抑制作用。TLR2参与了RAW264.7细胞川崎病模型中的炎症反应,其机制可能与p38MAPK途径有关。