芹菜素对人脑胶质瘤细胞凋亡作用的研究

本文主要研究芹菜素对人脑胶质瘤细胞 U87 凋亡的影响及机制.方法 : 应用 CCK8 法检测细胞增殖抑制率.流式细胞术检测细胞周期.Western-blot 检测凋亡相关蛋白 Bcl-2 及 Bax 的表达.结果 : ①芹菜素能抑制胶质瘤细胞 U87 的增殖.②不同浓度的芹菜素作用24h,G2 期细胞所占比例呈下降趋...     

柠檬苦素类化合物对人乳腺癌细胞(MCF-7)的生长抑制及细胞周期动力学的影响

为了探讨柠檬苦素类似物对乳腺癌细胞MCF-7生长抑制和对细胞周期的影响,应用MTT法和流式细胞仪检测癌细胞株生长和细胞周期.结果显示柠檬苦素类似物能明显抑制MCF-7的生长,抑制率高于70%,并随作用时间和剂量增加其效果增强;柠檬苦素可以影响细胞周期G     

芹菜素可抑制肿瘤生长

恶性肿瘤的发生与饮食结构关系密切，其中高蛋白、高脂肪食物与结肠癌，乳腺癌等肿瘤的发生呈正相关，而高纤维素、高维生素则可起到预防作用，降低肿瘤发生率。因此，良好的饮食习惯和饮食结构是预防恶性肿瘤的重要措施之一，一些与预防肿瘤发生的相关食物因素亦被列入研究范畴之内，有的在理论上已取得了很大进展，其中芹菜素与肿瘤发生发展的关系已被专家报道。     

高效液相色谱法测定芹菜中芹菜素含量

建立一种测定芹菜中芹菜素含量的高效液相色谱法,测定湖南不同地区的芹菜中芹菜素含量。采用高效液相色谱法,色谱柱为Kromasil C18流动相为乙腈和水（35：65）,流速1．0mL／min,检测波长270nm,柱温为35℃,进样量：10μL,检出限：18ng／mL。在10～160μg／mL范围内呈良好的线性关系（r^2=0．9974）,芹菜素平均回收率102％,（RSD=1．91％）。该方法操作简便、快速、分离度,灵敏度高,适用于芹菜素的测定。     

芹菜素对癌细胞作用机理的研究进展

芹菜素是芹菜中含有的一种重要的黄酮类物质,对多种癌细胞都有抑制其生长和促使其凋亡的作用,但是它对于癌细胞产生作用的具体机制尚未得到全面准确的阐释.本文参考近年来对芹菜素抗癌作用的研究的相关文献,分别对芹菜素对一些癌细胞的作用机制做了归纳和探讨.芹菜素对癌细胞作用的机理研究已经深入到细胞和分子水平,抑癌机理包括对基因和蛋白的抑制或激活,对信号因子的调节,干预酶发挥作用等.对芹菜素的抗癌作用机理的研究是通过饮食对癌症进行化学预防的一个重要部分,芹菜素作为癌症化学预防制剂具有广阔的应用前景.     

水溶性芹菜素的合成

对芹菜素进行结构修饰,通过磺化反应制备出水溶性的芹菜素磺化产物。并采用红外光谱、质谱和核磁共振氢谱对其进行结构表征。确定最佳反应条件为,每克芹菜素加入浓硫酸6ml,反应时间60min,反应温度15℃。得到芹菜素磺酸钠深黄色针状晶体,产率为83.5%。     

芹菜素对癌细胞作用机理的研究进展

芹菜素是芹菜中含有的一种重要的黄酮类物质,对多种癌细胞都有抑制其生长和促使其凋亡的作用,但是它对于癌细胞产生作用的具体机制尚未得到全面准确的阐释。本文参考近年来对芹菜素抗癌作用的研究的相关文献,分别对芹菜素对一些癌细胞的作用机制做了归纳和探讨。芹菜素对癌细胞作用的机理研究已经深入到细胞和分子水平,抑癌机理包括对基因和蛋白的抑制或激活,对信号因子的调节,干预酶发挥作用等。对芹菜素的抗癌作用机理的研究是通过饮食对癌症进行化学预防的一个重要部分,芹菜素作为癌症化学预防制剂具有广阔的应用前景。      

槲皮素和芹菜素对高尿酸血症大鼠血尿酸及抗氧化能力的影响

目的：研究同等剂量的槲皮素和芹菜素对腺嘌呤+盐酸乙胺丁醇诱导高尿酸血症大鼠血尿酸及抗氧化能力的影响。方法：SD大鼠随机分为5组,空白对照组、模型对照组、别嘌醇组、槲皮素组和芹菜素组。利用腺嘌呤加盐酸乙胺丁醇片灌胃诱导SD大鼠制备高尿酸血症模型,槲皮素和芹菜素预防治疗3周,测定肝脏和血清中相关的酶活性及生化指标。结果：与模型组相比,槲皮素和芹菜素均能显著降低高尿酸血症大鼠血尿酸(SUA)、尿素氮(SUN)、血肌酐(SCr)和丙二醛(MDA)的水平,提高超氧化物歧化酶(SOD)、总抗氧化能力(T-AOC)的水平。结论：槲皮素和芹菜素均能很好的控制高尿酸血症大鼠血清尿酸水平,并且能够增强高尿酸血症大鼠的抗氧化和清除氧自由基的能力,减少脂质过氧化。     

芹菜素对自由基致DNA损伤的保护作用及机制

运用DPPH自由基和 ·OH反应模型和酶标仪观察芹菜素(apigenin,API)对自由基的淬灭效应,以CuSO4-Phen-VC-H2O2-DNA化学发光体系测定API对 ·OH致DNA损伤的抑制作用,以探讨低剂量API对自由基致DNA损伤的保护效果及可能的作用机制,为以API为基础的膳食干预研究提供依据。结果表明：在30min时间内,API质量浓度为25、50、100、200μg/mL时,对DPPH自由基清除率分别为8.80%、28.4%、37.4%和62.8%。当质量浓度为200、100、50μg/mL时,API对 ·OH清除率分别为50.2%、35.4%和25.4%。在DNA化学发光体系中,25～100μg/mL API对DNA损伤产物发光抑制率为5.6%～16.9%,并使其受损时间延长35～50min。低剂量的API能有效清除DPPH自由基和 ·OH,抑制 ·OH引发的DNA损伤程度,并延迟其受损伤的时间。API清除自由基的效果及保护DNA损伤的能力与其质量浓度有关。     

芹菜素与锌配合反应的研究

本实验研究了芹菜素与锌的配位物的合成,确定合成芹菜素一锌配合物的最佳条件为pH值9．5,反应温度30℃,反应时间70min。在此条件下得率为82．62％。芹菜素一锌配合物在水中的溶解度为1．6mg／ml,约为原芹菜素的溶解度的80倍。芹菜素与锌的配合比为2：1。     

Lactoferricin treatment decreases the rate of cell proliferation of a human colon cancer cell line

Food components modify the risk of cancer at a large number of sites but the mechanism of action is unknown. In the present investigation, we studied the effect of the peptide lactoferricin derived from bovine milk lactoferrin on human colon cancer CaCo-2 cells. The cells were either untreated or treated with 2.0, 0.2, or 0.02 μM lactoferricin. Cell cycle kinetics were investigated with a bromodeoxyuridine DNA flow cytometric method. The results show that lactoferricin treatment slightly but significantly prolonged the S phase of the cell cycle. Lactoferricin treatment lowered the level of cyclin E1, a protein involved in the regulation of genes required for G₁/S transition and consequently for efficient S phase progression. The slight prolongation of the S phase resulted in a reduction of cell proliferation, which became more apparent after a long treatment time.     

Effects of phleomycin-induced DNA damage on the fission yeast Schizosaccharomyces pombe cell cycle

The effect of phleomycin, a bleomycin-like antibiotic, has been investigated in the fission yeast, Schizosaccharomyces pombe. We report that in response to phleomycin-induced DNA damage, growth was inhibited and S. pombe cells arrested in the G2-phase of the cell cycle. DNA repair mutants rad9 and rad17 did not arrest and were hypersensitive to phleomycin. Cell cycle mutants that entered mitosis without monitoring the completion of DNA replication also displayed an increased sensitivity to this DNA-damaging agent. Thus, phleomycin could be used as a tool in the fission yeast S. pombe model system for the study of DNA damage and cell cycle checkpoints, or as a new selective agent.     

The mechanism underlying proliferation-inhibitory and apoptosis-inducing effects of curcumin on papillary thyroid cancer cells

Recently, many studies on health benefits associated with curcumin have been reported. In this study, the effects of curcumin on apoptosis of papillary thyroid cancer cell line K1 and its potential mechanisms were investigated. Curcumin was found to significantly inhibit cell viability and promoted cell apoptosis in a dose-dependent manner. Moreover, curcumin-induced cell apoptosis was characterized with a rapid stimulation of reactive oxygen species (ROS) production. Furthermore, curcumin-induced ROS generation led to the loss of mitochondrial membrane potential (MMP) and the disturbance of intracellular Ca²⁺ concentration. A decrease in expression of Bcl-2 and the cleavage of poly ADP-ribose polymerase (PARP) were observed after exposure to curcumin. Results of this study may elucidate the curcumin-induced apoptosis effects on K1 cells. Thus, our results indicate a role of curcumin as health-promoting food ingredient, as well as a potential chemotherapeutic agent which is able to fight against papillary thyroid cancer.     

Effects of a novel DNA-damaging agent on the budding yeast Saccharomyces cerevisiae cell cycle

We have investigated the effects on Saccharomyces cerevisiae of a novel antitumour agent (FCE24517 or Tallimustine) which causes selective alkylations to adenines in the minor groove of DNA. Tallimustine, added to wild-type cells for short periods, reduced the growth rate and increased the percentage of budded cells and delayed the cell cycle in the late S+G₂+M phases. In the rad9Δ null mutant cells, Tallimustine treatment did not affect growth rate and the percentage of budded cells but greatly reduced cell viability compared to isogenic cells. Consistent with a role of RAD9 in inducing a transient delay in G₂ phase which preserves cell viability, the potent cytotoxic effect of the drug on rad9Δ cells was alleviated by treatment with nocodazole. Tallimustine was also found to delay the resumption from G₁ arrest of wild-type but not of rad9Δ cells. These data indicate that the effects of Tallimustine on cell cycle progression in yeast are mediated by the RAD9 gene product. From our data it appears that yeast could be a valuable model system to study the mode of action of this alkylating drug and of minor groove alkylators in general.     

芹菜素防治2型糖尿病的研究进展

本文拟整合目前关于芹菜素用于预防和治疗2型糖尿病(type 2 diabetes mellitus,T2DM)和肥胖的研究成果,重点强调芹菜素可作用于β细胞、脂肪细胞、肝细胞以及骨骼肌细胞上的各种分子靶点,调节不同的信号转导,而保护β细胞功能和改善外周组织胰岛素敏感性,对进一步开发芹菜素衍生的一些功能性食物作为糖尿病的替代疗法具有指导意义。同时讨论芹菜素药理作用研究中存在的争议,以及后续研究中需要加强的方面。      

瘤果黑种草子总黄酮成分对结肠癌细胞株SW480增殖、迁移能力的影响及机制

目的探讨瘤果黑种草子总黄酮成分对人结肠癌细胞株SW480增殖、迁移能力的影响及可能的作用机制。方法用不同浓度的瘤果黑种草子总黄酮成分药物干预的结肠癌细胞株SW480,MTT法检测SW480细胞株的增殖能力,倒置显微镜观察对结肠癌细胞株SW480细胞形态的影响,划痕实验检测对细胞的迁移能力的影响,实时荧光定量PCR检测瘤果黑种草子总黄酮成分对细胞中BECN1、MAPILC3B基因表达的影响。结果瘤果黑种草子总黄酮对人结肠癌细胞株SW480体外增殖的抑制作用明显,并呈浓度依赖性抑制人结肠癌细胞株SW480的增殖,在25μg/mL时达到最大的抑制率,抑制率为81.28%。倒置显微镜观察,用瘤果黑种草子总黄酮成分药物干预后,人结肠癌细胞株SW480形态学发生明显变化,瘤果黑种草子总黄酮成分可抑制人结肠癌细胞株SW480迁移能力,同时,可上调自噬相关基因BECN1、MAPILC3B的表达量。结论瘤果黑种草子总黄酮成分可抑制人结肠癌细胞株SW480的增殖、迁移能力,机制可能与能影响细胞中BECN1、MAPILC3B基因表达量有关。     

Optimization of ultrasonic-assisted enzymatic hydrolysis for the extraction of luteolin and apigenin from celery

The extraction of flavonoids is of increasing interest because of their various pharmacological effects. This study is the first attempt for the ultrasonic-assisted enzymatic hydrolysis (USAEH) applied in the extraction of 2 bioactive flavonoid compounds in celery--luteolin and apigenin. The quantitative yields of luteolin and apigenin were determined by high-performance liquid chromatography (HPLC). To achieve high yields of extracted compounds, the procedure was optimized with regard to the relative parameters involved. The optimal conditions for enzymatic hydrolysis using pectinase treatment were a reaction time of 30 min and a concentration of 0.4 mg/mL at pH 3 for luteolin and pH 5.5 for apigenin. The optimal ultrasonic parameters were an exposure period of 30 min at a temperature of 25 °C using a power source of 80 W. Under these optimal conditions, the yields of luteolin and apigenin were increased to 42.5 and 25.3 mg/g, respectively, which represented a 26.1-fold and a 32.2-fold increase in the yields of these 2 compounds, respectively, compared with the control model of aqueous extraction without enzyme or ultrasonic treatment.     

紫花地丁芹菜素清除DPPH自由基稳定性研究

目的研究不同外界因素对紫花地丁芹菜素抗氧化稳定性的影响。方法紫花地丁芹菜素标准品经乙醇溶解,采用清除DPPH自由基法测定其抗氧化活性,研究不同pH、温度、光照条件、一些常见金属离子及防腐剂对样品抗氧化性的影响。结果紫花地丁芹菜素具有较强的耐热性;在酸性环境中抗氧化活性保持较好,在碱性环境中抗氧化活性很快丧失;金属离子(Na~+、K~+、Ca~(2+)、Mg~(2+))对紫花地丁芹菜素的稳定性影响不明显,而光照、山梨酸钾则会降低其活性。结论外界环境因素对紫花地丁芹菜素抗氧化能力存在不同程度的影响,建立合适的储存条件可以显著增强紫花地丁芹菜素的抗氧化能力。     

玉米蛋白粉中黄体素、玉米黄素对乳腺癌细胞增殖的影响

研究玉米蛋白粉中黄体素、玉米黄素对乳腺癌细胞增殖的影响.体外培养MCF-7、SHZ细胞,培养时添加不同浓度的黄体素和玉米黄素,利用MTT法、HE染色法、扫描电镜等方法进行抗大鼠乳腺癌细胞增殖作用的研究.黄体素和玉米黄素对MCF-7细胞增殖的影响不显著,黄体素在体外对大鼠乳腺癌细胞的增殖效果也不明显,玉米黄素则在体外具有显著的抑制SHZ细胞增殖的作用.进一步研究表明:经玉米黄素作用的细胞在HE染色中,可见细胞核碎裂;扫描电镜可见细胞微绒毛消失,细胞膜表面呈现大量的凋亡小体.玉米蛋白粉中黄体素、玉米黄素对SHZ细胞生长的抑制作用具有较大的差异.     

Suillus collinitus methanolic extract increases p53 expression and causes cell cycle arrest and apoptosis in a breast cancer cell line

In the present work, methanolic, ethanolic and boiled water extracts of Suillus collinitus were chemically characterised and submitted to an evaluation of their bioactive properties (antioxidant potential and cytotoxic activity in tumor cell lines). Phenolic acids and sugars were identified chromatographically and quantified in the methanolic and boiled water extracts, respectively. S. collinitus ethanolic extract had the highest antioxidant activity. Nevertheless, with respect to cell growth inhibition, the methanolic extract was the most potent extract, particularly in MCF-7 cells (GI(50) 25.2±0.2μg/ml). Moreover, the GI(50) concentration of this extract induced a G1 cell cycle arrest, with a concomitant decrease in the percentage of cells in the S phase. Furthermore, it caused an increase in the percentage of apoptotic cells, from 6.0±0.2% in untreated cells, to 15.3±2.0% in cells treated with the GI(50) concentration and to 16.3±2.0% in cells treated with 2×GI(50) concentration. In addition, 48h treatment with the GI(50) concentration caused a strong increase in the levels of p53, p21, and cleaved PARP, together with a decrease in Bcl-2 and XIAP. Results indicate that S. collinitus may be a promising source of bioactive compounds. Particularly, its methanolic extract appears to have a p53-mediated effect on the normal cell cycle distribution and apoptosis induction in a human breast tumor cell line.