杠柳毒苷体外抑制肝癌细胞和乳腺癌细胞增殖的实验研究

目的 探讨杠柳毒苷在体外对人乳腺癌MDA-MB-468细胞和人肝癌HepG2细胞增殖的影响。方法 MTT法观察杠柳毒苷对人乳腺癌MDA-MB-468细胞和人肝癌HepG2细胞增殖的抑制作用,流式细胞术观察杠柳毒苷对两种肿瘤细胞的细胞增殖周期作用。结果 与对照组比较,杠柳毒苷能明显抑制两种肿瘤细胞的增殖,其抑制率与药物浓度和作用时间呈正相关。流式细胞仪检测发现,杠柳毒苷对乳腺癌MDA-MB-468细胞和肝癌HepG2细胞持续作用24 h后,可以使G₀/G₁期细胞增多,G₂/M期细胞减少。结论 杠柳毒苷具有抑制乳腺癌MDA-MB-468细胞和肝癌HepG2细胞增殖的作用,并可将乳腺癌MDA-MB-468细胞和肝癌HepG2细胞的细胞生长周期阻滞在G₀/G₁期。     

杠柳苷元抑制人乳腺癌细胞增殖作用的研究

目的 观察杠柳苷元(periplogenin)对人乳腺癌细胞MCF7的抑制作用并考察其抑制作用的机理.方法 使用四氮唑盐(MTT)法测定杠柳苷元对MCF7细胞的增殖抑制效果,并使用蛋白免疫印迹法测定其中凋亡蛋白的表达.结果 杠柳苷元对MCF7细胞起到了明显的抑制作用,其抑制作用呈剂量依赖性,蛋白免疫印迹法也观察到杠柳苷元促进MCF7细胞内凋亡相关蛋白的表达,其表达呈时间依赖性.结论 杠柳苷元具有显著的体外抑制MCF7细胞增殖的作用,其抑制作用是通过促进MCF7细胞凋亡而发挥的.     

杠柳毒苷在大鼠体内的药动学研究

目的考察杠柳毒苷iv给药在大鼠体内的药动学过程。方法大鼠iv给予低、中、高剂量(0.37、0.74、1.48mg/kg)杠柳毒苷后于不同时间点采血,血浆样品经甲醇沉淀蛋白-C18固相萃取处理,HPLC-UV法测定不同时间点大鼠血浆中杠柳毒苷药物浓度。用DAS药动学数据软件计算药动学参数。结果低、中、高剂量组杠柳毒苷的分布相半衰期t1/2α分别为1.49、2.32、3.48min,消除相半衰期t1/2β分别为14.00、12.37、15.44min,无显著性差异。AUC0-60分别为8.581、19.782、50.615mg/L·min,与剂量呈线性相关。结论杠柳毒苷iv给药在大鼠体内分布及消除迅速,其体内过程符合二房室模型,在0.37～1.48mg/kg符合线性动力学过程。     

香加皮杠柳苷对小鼠骨髓瘤细胞增殖、凋亡及移植成瘤的影响及作用机制

目的 研究香加皮杠柳苷(CPP)对小鼠骨髓瘤细胞增殖、凋亡及移植成瘤的影响及作用机制.方法 通过用不同浓度的香加皮杠柳苷对SP2/0小鼠骨髓瘤细胞及小鼠体内移植瘤进行干预处理,MTT法检测CPP处理的SP2/0小鼠骨髓瘤细胞的增殖抑制率,流式细胞仪检测小鼠骨髓瘤细胞的凋亡率,Western blot检测小鼠骨髓瘤细胞及移植瘤中IL-6和DKK1蛋白的表达水平.结果 不同浓度CPP能抑制SP2/0小鼠骨髓瘤细胞增殖,加速SP2/0小鼠骨髓瘤细胞凋亡,在裸鼠体内,不同浓度CPP对抑制骨髓瘤移植成瘤,同时降低骨髓瘤细胞和移植瘤中IL-6和DDK1蛋白的表达水平.结论 香加皮杠柳苷能够通过抑制IL-6和DDK1表达,阻断Wnt信号来达到治疗小鼠骨髓瘤的作用,有望成为治疗多发性骨髓瘤及骨髓瘤骨病的新药物.     

杠柳毒苷在大鼠体肠吸收动力学研究

目的考察杠柳毒苷在大鼠小肠内的吸收情况。方法采用大鼠在体单向肠灌流模型,用高效液相色谱法对灌流液中的杠柳毒苷进行分析。结果杠柳毒苷在不同浓度下未发现饱和现象,其吸收速率常数(Ka)和表观吸收系数(Papp)基本保持不变。结论杠柳毒苷在小肠的吸收机制为被动扩散,在临床应用及制剂研究中应考虑其吸收机制。     

基于斑马鱼模型的杠柳毒苷肝毒性评价

目的 基于斑马鱼模型初步探讨杠柳毒苷的毒性靶器官和潜在作用机制。方法 将斑马鱼(4 days post fertilization,4 dpf)暴露于不同浓度(低浓度1μg·mL^-1,高浓度1.5μg·mL^-1)的杠柳毒苷溶液中24 h,统计杠柳毒苷对斑马鱼的致死率;10%致死剂量下(10)暴露24 h后,基于肝脏面积变化,吖啶橙染色,肝脏组织病理切片,谷丙转氨酶(ALT)与谷草转氨酶(AST)活性变化等指标评价杠柳毒苷的肝毒性;通过网络药理学与分子对接技术预测杠柳毒苷肝毒性潜在作用机制,并通过实时荧光定量PCR(real-time PCR,RT-PCR)对预测靶点进行验证。结果 杠柳毒苷对斑马鱼的亚致死浓度(LC₁₀)为1.612 6μg·mL^-1,亚致死浓度暴露条件下,与空白组相比,杠柳毒苷能够引起斑马鱼肝脏面积减小和明显的肝脏细胞凋亡,组织病理切片结果显示杠柳毒苷能够诱导肝细胞出现结构排列松散紊乱以及明显空泡化等病理特征。此外,杠柳毒苷能够显著升高斑马鱼ALT...     

杠柳毒苷在大鼠体内的组织分布

目的 考察杠柳毒苷在大鼠体内的组织分布.方法 采用高效液相色谱法测定大鼠静脉注射杠柳毒苷后,组织样品中杠柳毒苷的质量浓度.结果 大鼠iv杠柳毒苷0.74 mg/kg,2、10、20 min后肝中杠柳毒苷的质量浓度分别为(2.447±0.687)、(0.6310±0.272)、(0.2924±0.228)μg/g,在肝中...     

Cucurbitacin E inhibits the proliferation of hepatoma cells in vitro and in vivo through induction of G2/M phase arrest

Objective Cucurbitacins are the highly oxygenated tetracyclic triterpenes,which are predominantly found in the Cucurbitaceae family but are also present in several other families of the plant kingdom.A number of compounds of this group have been investigated for their cytotoxic,hepatoprotective,anti-inflammatory,cardiovascular and anti-diabetic activities.In China,the cucurbitacin preparation,which contains mostly cucurbitacin B and cucurbitacin E,has been clinically used for the treatment of the primary liver carcinoma.It has been previously reported that cucurbitacin E could produce cytotoxicity against a variety of cancer cells,and various mechanisms were implicated in its cytotoxic effect.The present study is to investigate the effect of cucurbitacin E on hepatoma cells in vitro and in vivo and to study their potential mechanisms of action.Methods The MTT assay was used to assess the viability of human HepG2 and BEL7402 hepatoma cells in vitro after treatment with different concentrations of cucurbitacin E.The cell cycle distribution was determined by flowcytometric analysis after propidium iodide(PI)staining.The cell cycle-related proteins were detected using western blotting analysis.Implanted mouse hepatoma H22 model was built to evaluate the growth inhibitory effect of cucurbitacin E in vivo in mice.Results Our studies found that cucurbitacin E(10-300 nM)produced anti-proliferative effect on human HepG2 and BEL7402 hepatoma cells in vitro without cytotoxicity.According to flowcytometric analysis,cucurbitacin E arrested the cell cycle at G2/M phase in both HepG2 and BEL7402 hepatoma cells after 24 h treatment.Cucurbitacin E induced the decrease in the level of CDK1 protein and the increase in the level of p21 protein,but had no effect on the levels of cyclin A,cyclin B1 and Cdc25C protein.In in vivo anti-tumor experiment,cucurbitacin E had significant inhibitory effects on the growth of mouse H22 hepatoma cells.Conclusions Cucurbitacin E inhibited the proliferation of hepatoma cells in vitro and in vivo,at least in part,through induction of cell cycle arrest at G2/M phase,which was mediated by concomitant upregulation of p21 and downregulation of CDK1.We consider that cucurbitacin E may be useful in the treatment of liver cancer.     

Involvement of the p38 MAPK signaling pathway in S‐phase cell‐cycle arrest induced by Furazolidone in human hepatoma G2 cells

Given the previously described essential role for the p38 mitogen‐activation protein kinase (p38 MAPK) signaling pathway in human hepatoma G2 cells (HepG2), we undertook the present study to investigate the role of the p38 MAPK signaling pathway in cell‐cycle arrest induced by Furazolidone (FZD). The aim of this study was to determine the effects of FZD on HepG2 cells by activating and inhibiting the p38 MAPK signaling pathway. The cell cycle and proliferation of HepG2 cells treated with FZD were detected by flow cytometry and MTT assay in the presence or absence of p38 MAPK inhibitors (SB203580), respectively. Cyclin D1, cyclin D3 and CDK6 were detected by quantitative real‐time PCR and western blot analysis. Our data showed that p38 MAPK became phosphorylated after stimulation with FZD. Activation of p38 MAPK could arise S‐phase cell‐cycle arrest and suppress cell proliferation. Simultaneously, inhibition of the p38 MAPK signaling pathway significantly prevented S‐phase cell‐cycle arrest, increased the percentage of cell viability and decreased the expression of cyclin D1, cyclin D3 and CDK6. These results demonstrated that FZD arose S‐phase cell‐cycle arrest via activating the p38 MAPK signaling pathway in HepG2 cells. Cyclin D1, cyclin D3 and CDK6 are target genes functioning at the downstream of p38 MAPK in HepG2 cells induced by FZD. Copyright © 2012 John Wiley & Sons, Ltd.     

白花丹醌对人肝癌细胞HepG2、SMMC-7721增殖及其Bax/Bcl-2、Cyclin D1 mRNA表达的影响

目的探索白花丹醌对人肝癌细胞HepG2、SMMC-7721增殖的影响及其影响机制。方法人肝癌细胞HepG2和SMMC-7721分别与白花丹醌共培养,通过显微图像、MTT法检测了白花丹醌对上述两种肝癌细胞增殖情况的影响,利用实时荧光定量PCR(Qpcr)检测其Bax/Bcl-2,Cyclin D1mRNA表达的影响。结果显微照像和MTT法测定都表明白花丹醌能明显地抑制两种肝癌细胞的增殖;Qpcr检测表明,对HepG2和SMMC-7721,白花丹醌能明显上调Bax/Bcl-2mRNA比值(P=0.0017和P=0.00104),同时明显下调Cy-clin D1 mRNA水平(P=0.0287和P=0.0165)。结论白花丹醌能抑制HepG2、SMMC-7721的增殖,其机制与Bax/Bcl-2比值上升和Cyclin D1转录水平下降有关。     

晚期糖基化终产物对人肝癌细胞HepG2增殖的影响

目的探讨糖尿病晚期糖基化终产物(AGEs)对肝癌细胞HepG2增殖的影响及其机制。方法体外培养人肝癌细胞HepG2,以终浓度分别为100、200和400μg/ml的AGEs处理细胞24h,并设正常对照组进行比较。运用细胞计数试剂盒8研究AGEs对HepG2增殖的影响,流式细胞术检测细胞周期的改变,Western blot检测肝癌细胞抗凋亡基因表达。结果 AGEs呈浓度依赖性显著促进HepG2细胞增殖(P<0.05)。与对照组比较,200μg/ml AGEs干预24h后可以减少HepG2细胞G1期百分率,同时增加S期百分率(P<0.05)。AGEs可致细胞抗凋亡基因B细胞淋巴瘤-白血病2(Bcl-2)相关蛋白表达增加。结论 AGEs能促进HepG2细胞的增殖,其机制可能与上调Bcl-2相关蛋白表达,加速细胞G1期向S期转换相关。     

Pomegranate peel extract polyphenols induced apoptosis in human hepatoma cells by mitochondrial pathway

This study was aimed to investigate the influence of pomegranate peel polyphenols (PPPs) on the proliferation and apoptosis of HepG2 cells (a kind of human hepatoma cells) and the related mechanism. The inverted fluorescence microscope and the flow cytometer (FCM) were used to test the changes of the cellular morphology, cell cycle, apoptosis, reactive oxygen species (ROS) and mitochondrial transmembrane potential (Δψm). The kit was used to measure the activities of caspase-3/9, and Western Blot was used to detect the expressions of apoptosis-associated proteins including p53, Bcl-2/Bax, Cyt-c and PARP. The results showed that the cells cycle of HepG2 arrested at the S-phase by PPPs and the amount of the early apoptotic cells and ROS level were increased obviously, the level of Cyt-c and the activity of Caspase-3/9 markedly were also increased by PPPs, as well as the ratio of Bax/Bcl-2 and the protein expressions of P53. It was concluded that PPPs could inhibit the growth of HepG2 cells by blocking the cell cycle and inducing the mitochondrial apoptotic pathway in a dose-dependent manner.     

腺苷体外对人肝癌HepG2细胞凋亡的诱导作用及其作用机制

目的研究腺苷及其代谢途径对人肝癌HepG2细胞凋亡的诱导作用及其机制。方法将腺苷2.0mmol.L-1作用于HepG2细胞24和48h,采用流式细胞术(FCM)测定细胞周期及凋亡率;观察腺苷膜转运体抑制剂双嘧达莫、腺苷脱氨酶抑制剂红-9-(2-羟基-3-壬烷基)腺嘌呤(EHNA)和腺苷激酶抑制剂5′-氨基5′-脱氧腺苷(AMDA)对腺苷抑制细胞存活的影响,应用MTT法测定细胞存活率;应用Western蛋白印迹法检测P53和Bcl-2蛋白的表达。结果腺苷与HepG2细胞作用24和48h,HepG2细胞出现特征性的亚二倍体凋亡峰,细胞凋亡百分率分别由对照组的(1.2±0.4)%和(4.1±1.6)%增加到(24.3±4.8)%和(38.6±7.4)%,细胞周期阻滞于G0/G1期。腺苷与HepG2细胞作用24h明显抑制细胞存活,P53表达明显增强,Bcl-2表达降低。预先分别给予双嘧达莫,AMDA和AMDA+双嘧达莫处理后,各处理组HepG2细胞存活率较腺苷组升高,细胞凋亡百分率和P53表达降低,Bcl-2表达无明显变化;EHNA预处理组细胞存活率、细胞凋亡百分率、P53和Bcl-2表达与腺苷组比较均无明显变化。结论腺苷可诱导HepG2细胞凋亡,腺苷在胞内可能通过腺苷激酶而不是通过转氨酶的代谢途径参与诱导细胞凋亡的过程。腺苷对HepG2细胞凋亡的诱导作用还可能与其增加P53蛋白表达有关。     

Antiproliferative effects of quercetin through cell cycle arrest and apoptosis in human breast cancer MDA-MB-453 cells

To explore the anticancer effects of the flavonoid quercetin on human breast cancer MDA-MB-453 cells via cell cycle regulation and the induction of apoptosis, the antiproliferative effect of quercetin was first examined by MTT assay. When MDA-MB-453 cells were treated with quercetin for various periods of time (3–24 hrs) and at various doses (1–100 μM), cell growth decreased significantly in a time-and dose-dependent manner. To elucidate the mechanism underlying the antiproliferative effect of quercetin, cell cycle progression and the induction of apoptosis in MDA-MB-453 cells exposed to 100 μM quercetin for 24 hrs were investigated. Quercetin caused a remarkable increase in the number of sub-G1 phase cells, and an Annexin-V assay revealed that exposure to quercetin affected apoptosis. Moreover, treatment with quercetin increased Bax expression but decreased Bcl-2 expression. Cleaved caspase-3 and PARP expression was also increased by quercetin. Thus, quercetin has probable anticancer activity. Our results suggest the existence of multiple pathways for the induction of cell cycle arrest and apoptosis by quercetin.     

Estrogen receptor enhances the antiproliferative effects of trichostatin A and HC-toxin in human breast cancer cells

Trichostatin A, an antifungal antibiotics, and HC-toxin are potent and specific inhibitors of histone deacetylase activity. Histone deacetylase inhibitors are new class of chemotherapeutic drugs able to induce tumor cell apoptosis and/ or cell cycle arrest. In this study, the antiproliferative activities of trichostatin A and HC-toxin were compared between estrogen receptor positive human breast cancer cell MCF-7 and estrogen receptor negative human breast cancer cell MDA-MB-468. Trichostatin A and HC-toxin showed potent antiproliferative activity in both MCF-7 and MDA-MB-468 cells. In MCF-7 cells that contain high level estrogen receptor, trichostatin A and HC-toxin brought about three-times more potent cell growth inhibitory effect than estrogen receptor negative MDA-MB-468 cells. Both trichostatin A and HC-toxin showed cell cycle arrest at G₂/M phases of MCF-7 and MDA-MB-468 cells in a dose- and time- dependent manner. Trichostatin A and HC-toxin also induced apoptosis from MCF-7 and MDA-MB-468 cells in a dose- and time-dependent manner. Results of this study suggested that antiproliferative effects of trichostatin A and HC-toxin might be involved in estrogen receptor signaling pathway, but cell cycle arrest and apoptosis of trichostatin A and HC-toxin might not be involved in estrogen receptor system of human breast cancer cells.