吡非尼酮对肝癌HepG2细胞增殖和凋亡的影响(“豪森杯”优秀论文三等奖)

目的：研究吡非尼酮（pirfenidone,PF）对人肝癌细胞系HepG2增殖和凋亡的影响。方法：CCK-8法测定不同浓度PF对HepG2细胞增殖活性的影响;Hoechst 33258荧光染色法观察PF处理后HepG2细胞形态的变化;流式细胞仪检测细胞凋亡率。结果：PF对HepG2细胞具有显著增殖抑制作用,并呈浓度和时间依赖性;Hoechst 33258染色可见PF处理后细胞出现典型的凋亡形态学变化;流式细胞仪检测结果显示,与空白组比较,PF处理后的HepG2细胞凋亡率显著增加（P﹤0.01）。结论：PF对人肝癌细胞系HepG2细胞增殖具有抑制作用,且与诱导HepG2细胞凋亡有关。     

Atrazine exposure leads to altered growth of HepG2 cells

Atrazine is one of the most commonly used herbicides in the United States. While effective on target plants, it has been associated with harmful health effects in non-target organisms such as fish, amphibians and mammals. In this study, growth effects on human liver cells were determined after exposure to increasing concentrations of this herbicide. Growth of immortalized human hepatoma HepG2 cells was inhibited by atrazine concentrations of 625 ppb after 72 h exposure and flow cytometry analysis demonstrated HepG2 cells exposed to 100 ppb atrazine accumulated in S phase after 48 h compared to untreated cells. Expression of cell cycle specific cyclin proteins was altered after atrazine exposure with cyclin E levels significantly decreased after a 24 h exposure and cyclin B levels decreased after 48 h. This study demonstrates that relatively low levels of atrazine exposure can affect growth and lead to disruptions in the cell cycle regulation of immortalized human liver cells.     

Comparative cytotoxicity of nanosilver in human liver HepG2 and colon Caco2 cells in culture

The use of silver nanoparticles in food, food contact materials, dietary supplements and cosmetics has increased significantly owing to their antibacterial and antifungal properties. As a consequence, the need for validated rapid screening methods to assess their toxicity is necessary to ensure consumer safety. This study evaluated two widely used in vitro cell culture models, human liver HepG2 cells and human colon Caco2 cells, as tools for assessing the potential cytotoxicity of food‐ and cosmetic‐related nanoparticles. The two cell culture models were utilized to compare the potential cytotoxicity of 20‐nm silver. The average size of the silver nanoparticle determined by our transmission electron microscopy (TEM) analysis was 20.4 nm. The dynamic light scattering (DLS) analysis showed no large agglomeration of the silver nanoparticles. The concentration of the 20‐nm silver solution determined by our inductively coupled plasma–mass spectrometry (ICP‐MS) analysis was 0.962 mg ml^–1. Our ICP‐MS and TEM analysis demonstrated the uptake of 20‐nm silver by both HepG2 and Caco2 cells. Cytotoxicity, determined by the Alamar Blue reduction assay, was evaluated in the nanosilver concentration range of 0.1 to 20 µg ml^–1. Significant concentration‐dependent cytotoxicity of the nanosilver in HepG2 cells was observed in the concentration range of 1 to 20 µg ml^–1 and at a higher concentration range of 10 to 20 µg ml^–1 in Caco2 cells compared with the vehicle control. A concentration‐dependent decrease in dsDNA content was observed in both cell types exposed to nanosilver but not controls, suggesting an increase in DNA damage. The DNA damage was observed in the concentration range of 1 to 20 µg ml^–1. Nanosilver‐exposed HepG2 and Caco2 cells showed no cellular oxidative stress, determined by the dichlorofluorescein assay, compared with the vehicle control in the concentration range used in this study. A concentration‐dependent decrease in mitochondria membrane potential in both nanosilver exposed cell types suggested increased mitochondria injury compared with the vehicle control. The mitochondrial injury in HepG2 cells was significant in the concentration range of 1 to 20 µg ml^–1, but in Caco2 cells it was significant at a higher concentration range of 10 to 20 µg ml^–1. These results indicated that HepG2 cells were more sensitive to nanosilver exposure than Caco2 cells. It is generally believed that cellular oxidative stress induces cytotoxicity of nanoparticles. However, in this study we did not detect any nanosilver‐induced oxidative stress in either cell type at the concentration range used in this study. Our results suggest that cellular oxidative stress did not play a major role in the observed cytotoxicity of nanosilver in HepG2 and Caco2 cells and that a different mechanism of nanosilver‐induced mitochondrial injury leads to the cytotoxicity. The HepG2 and Caco2 cells used this study appear to be targets for silver nanoparticles. The results of this study suggest that the differences in the mechanisms of toxicity induced by nanosilver may be largely as a consequence of the type of cells used. This differential rather than universal response of different cell types exposed to nanoparticles may play an important role in the mechanism of their toxicity. In summary, the results of this study indicate that the widely used in vitro models, HepG2 and Caco2 cells in culture, are excellent systems for screening cytotoxicity of silver nanoparticles. These long established cell culture models and simple assays used in this study can provide useful toxicity and mechanistic information that can help to better inform safety assessments of food‐ and cosmetic‐related silver nanoparticles. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.     

Osthole induces G2/M cell cycle arrest and apoptosis in human hepatocellular carcinoma HepG2 cells

Context: Osthole [7-methoxy-8-(3-methyl-2-butenyl) coumarin] isolated from the fruit of Cnidium monnieri (L.) Cuss, one of the commonly used Chinese medicines listed in the Shennong’s Classic of Materia Medica in the Han Dynasty, had remarkable antiproliferative activity against human hepatocellular carcinoma HepG2 cells in culture.

Objectives: This study evaluated the effects of osthole on cell growth, nuclear morphology, cell cycle distribution, and expression of apoptosis-related proteins in HepG2 cells.

Materials and methods: Cytotoxic activity of osthole was determined by the MTT assay at various concentrations ranging from 0.004 to 1.0?µmol/ml in HepG2 cells. Cell morphology was assessed by Hoechst staining and fluorescence microscopy. Apoptosis and cell-cycle distribution was determined by annexin V staining and flow cytometry. Apoptotic protein levels were assessed by Western blot.

Results: Osthole exhibited significant inhibition of the survival of HepG2 cells and the half inhibitory concentration (IC₅₀) values were 0.186, 0.158 and 0.123?µmol/ml at 24, 48 and 72?h, respectively. Cells treated with osthole at concentrations of 0, 0.004, 0.02, 0.1 and 0.5?μmol/ml showed a statistically significant increase in the G2/M fraction accompanied by a decrease in the G0/G1 fraction. The increase of apoptosis induced by osthole was correlated with down-regulation expression of anti-apoptotic Bcl-2 protein and up-regulation expression of pro-apoptotic Bax and p53 proteins.

Conclusion: Osthole had significant growth inhibitory activity and the pro-apoptotic effect of osthole is mediated through the activation of caspases and mitochondria in HepG2 cells. Results suggest that osthole has promising therapeutic potential against hepatocellular carcinoma.     

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。     

不同浓度依托咪酯诱导人肝癌HepG2细胞体外凋亡的研究

目的探讨不同浓度的依托咪酯是否具有直接诱导人肝癌HepG2细胞凋亡的作用,寻找依托咪酯临床治疗的新途径。方法人肝癌细胞株HepG2体外扩增培养备用,选取不同浓度的依托咪酯E1、E2、E3和对照组（空白）,分别培养12h、24h、48h后观察。结果与空白对照组相比,培养12h、24h、48h后E1组、E2组人肝癌细胞株HepG2细胞凋亡率无明显差异（P〉0．05）,E3组凋亡率不断增加,具有显著性差异（P〈0．05）;随着培养时间的延长及浓度的不断增加,E1与E2组对比人肝癌细胞株HepG2细胞凋亡率无明显差异（t=1．732,P〉0．05）,E1与E3组对比人肝癌细胞株HepG2细胞凋亡率具有显著性差异（t=1．864,P〈0．05）,E2与E3组对比人肝癌细胞株HepG2细胞凋亡率具有明显差异（f=1．691,P〈0．05）。结论依托咪酯在临床安全有效的浓度下不直接诱导人肝癌HepG2细胞的体外凋亡,浓度及时间达到一定峰值时可具有直接诱导人肝癌HepG2细胞体外凋亡的作用。     

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。     

红枣多糖对人肝癌 HepG2细胞的抑制作用

目的：研究红枣多糖对体外培养肝癌细胞增殖的抑制作用并初步探究其可能的作用机理。方法采用M T T法测定红枣多糖对体外培养的人肝癌细胞HepG2增殖的抑制作用;流式细胞术检测红枣多糖对人肝癌细胞HepG2周期和凋亡的影响;Real time RT-PCR检测红枣多糖对人肝癌细胞HepG2中Bcl-2和caspase3 mRNA表达的影响。结果 MTT检测发现随着药物浓度的增高OD值呈现梯度递减,红枣多糖对 HepG2的IC50＝13 mg／mL ,最高浓度40 mg／mL下所得最大抑制率为68．79％;流式细胞仪检测细胞凋亡结果可见早期凋亡率随药物浓度的增加而变大;流式细胞周期分析结果可见G0-G1期细胞数逐渐增多,S期细胞数有下降趋势,并有剂量依赖性;Real time RT-PCR检测发现Bcl-2凋亡抑制基因mRNA表达随药物浓度增高而降低,而凋亡关键基因caspase-3 mRNA的表达随药物浓度增高而升高。结论红枣多糖对体外培养的肝癌细胞增值具有抑制作用,将肝癌细胞HepG2阻滞于G1期,并通过下调Bc 1-2而上调caspase-3 mRNA表达诱导 HepG2细胞凋亡。     

丁酸钠调控HepG2细胞的增殖、凋亡和侵袭

目的 研究丁酸钠对人肝癌细胞HepG2增殖和凋亡的影响,并探讨可能的作用机制。方法 用不同浓度丁酸钠处理HepG2 细胞后,MTT方法检测细胞的增殖能力,流式细胞技术检测细胞周期的分布和细胞凋亡,Transwell小室检测丁酸钠对HepG2细胞侵袭能力的影响。免疫荧光法检测HDAC4蛋白在HepG2细胞中的表达及定位。蛋白质印迹法(Western Blot)检测HDAC4蛋白的表达水平。结果 随着丁酸钠处理浓度的增加和处理时间的延长,HepG2细胞增殖能力明显受抑制,细胞周期也发生阻滞,G1期细胞比例明显增加,而S期细胞比例明显减少。不同浓度(0,1,5,10 mmol/L)丁酸钠处理HepG2细胞24 h后,早期凋亡率分别为2.7％,4.5％,6.5％,6.7%,差异有统计学意义(F=15.1,P=0.001)。丁酸钠显著抑制细胞侵袭能力,侵袭细胞百分比分别降至72.7%(1 mmol/L)、41.7%(5 mmol/L)、21.3%(10 mmol/L),差异有统计学意义(F=202.1,P<0.001)。HDAC4蛋白在HepG2 细胞中呈阳性表达,主要位于细胞质中。丁酸钠明显抑制HDAC4蛋白的表达,并呈浓度依赖性。结论 丁酸钠抑制肝癌细胞系HepG2的增殖,调控细胞周期、促进凋亡,抑制细胞的侵袭能力。     

GL-V9, a newly synthetic flavonoid derivative, induces mitochondrial-mediated apoptosis and G2/M cell cycle arrest in human hepatocellular carcinoma HepG2 cells

We recently established that GL-V9, a newly synthetic flavonoid derivative, is an active cytotoxic component. In this study, we demonstrated that GL-V9 inhibited cells growth via inducing apoptosis and G2/M cell cycle arrest in human hepatocellular carcinoma HepG2 cells. Following the treatment of HepG2 cells with GL-V9, we observed poly (ADP-ribose) polymerase (PARP) cleavage and activation of caspase-3 and caspase-9, while caspase-8 remained unchanged. The expression ratio of Bcl-2/Bax was also decreased in GL-V9-treated cells. Meanwhile, the cell cycle-related proteins, such as cyclin B1, CDK1 and cdc25 were down-regulated in GL-V9-induced G2/M cell cycle arrest. Furthermore, we showed that GL-V9-induced apoptosis in HepG2 cells was achieved through mitochondrial pathway. It also regulated changes of mitochondrial membrane potential and increased the production of intracellular reactive oxygen species. Besides, the growth inhibitory effect of GL-V9 was examined in vivo using murine implanted tumor model. These studies indicate that GL-V9 shows promise as a therapeutic agent against human heptoma.     

地塞米松对顺铂诱导的HepG2细胞凋亡及Bcl-2和Caspase-3蛋白表达的影响

目的:探讨地塞米松对顺铂诱导HepG2细胞凋亡的影响,并观察Bcl-2和Caspase-3蛋白的表达。方法:HepG2细胞与顺铂及不同浓度的地塞米松共培养,RT-PCR检测Bcl-2、Caspase-3的mRNA表达,Western blot检测Bcl-2、Caspase-3蛋白表达,流式细胞术(FACS)检测各组HepG2细胞的凋亡情况。结果:随着地塞米松浓度的增加,HepG2细胞中Bcl-2蛋白表达量升高,Caspase-3蛋白表达量下降。同时细胞凋亡率降低。结论:地塞米松部分通过Bcl-2途径抑制肝癌细胞的凋亡,而Caspase-3又在调控细胞凋亡中起重要作用。     

Zinc inhibits aflatoxin B1-induced cytotoxicity and genotoxicity in human hepatocytes (HepG2 cells)

Aflatoxin B1 (AFB1) has strong carcinogenicity. Consumption of AFB1-contaminated agricultural products and the occurrence of hepatocellular carcinoma have received widespread attention. The aim of this paper was to investigate whether zinc supplementation could inhibit AFB1-induced cytotoxicity and genotoxicity in HepG2 cells and the mechanism of this inhibition. Our data suggest that zinc sources can relieve a certain degree of AFB1-induced cytotoxicity and genotoxicity by protecting against apoptotic body formation and DNA strand breaks, affecting S phase cell cycle arrest, reducing 8-OHdG formation, inhibiting global DNA hypomethylation and regulating gene expression in antioxidation, zinc-association and apoptosis processes. Consequently, zinc stabilizes the integrity of DNA and improves cell survival.These data provides new insights into the protective role of zinc in alleviating AFB1-induced cytotoxicity and mediating epigenetic changes in hepatocytes, demonstrating that zinc sources have detoxification properties in mycotoxin-induced toxicity.     

Effect of polyphenols on enniatins-induced cytotoxic effects in mammalian cells

Enniatins (ENs) are fungal secondary metabolites produced by genus Fusarium. The ENs exert antimicrobial and insecticidal effect, and has also been demonstrated cytotoxic effects on several mammalian cell lines. On the other hands, it has been proved that natural polyphenols have antioxidant effect. In this study, cell effects at low levels of exposure of four ENs (A, A₁, B and B₁) and five polyphenols (quercetin, quercetin-3-β-D-glucoside, rutin, myricetin and t-pterostilbene) present in wine; and the cytoprotective effect of these polyphenols exposed simultaneously with ENs in Chinese Hamster Ovary (CHO-K1) cells, were studied. Cell effects were determined by the MTT test after 24?h of exposure. All ENs showed cytotoxic effect. The IC₅₀ obtained ranged from 4.5?±?1.2 to 11.0?±?2.7 µM. The concentration of polyphenols tested ranged from 5 to 50 µM. Polyphenols did not show cytotoxicity and the cytoprotective effect of polyphenols varies depending on the EN tested. The cytoprotective effect of polyphenols in CHO-K1 cells exposed to ENs was as follow: quercetin, from 24 to 84%; quercetin-3-β-D-glucoside, from 12 to 76%; rutin, from 17 to 83%; myricetin, from 16 to 92% and pterostilbene from 25 to 100%. All polyphenols protected CHO-K1 cells against EN A₁ exposure.     

人参皂苷 Rg5通过抑制蛋白激酶 B信号通路调控肝癌 HepG2细胞生物学行为

目的 探讨人参皂苷Rg5对肝癌HepG2细胞生物学行为和蛋白激酶B(AKT)信号通路的影响.方法 采用四甲基偶氮唑盐微量酶反应比色法(MTT法)检测不同浓度人参皂苷Rg5对HepG2细胞24、48和72 h下的细胞存活率,并计算出半数抑制浓度(IC50)以筛选出合适的作用浓度.Transwell小室实验检测人参皂苷Rg5对细胞侵袭和迁移的影响,流式细胞仪检测人参皂苷Rg5对细胞周期和凋亡的影响,蛋白质印迹法(Western blotting)检测人参皂苷Rg5对细胞中AKT、磷酸化蛋白激酶B(p-AKT)、细胞周期蛋白D1(cyclin D1)、基质金属蛋白酶9(MMP-9)和B细胞淋巴瘤-2(Bcl-2)表达的影响.结果 与对照(0μmol/L)组相比,40、80和160μmol/L人参皂苷Rg524 h下细胞存活率降低(P<0.05),20、40、80和160μmol/L人参皂苷Rg548 h下细胞存活率明显降低(P<0.05),不同浓度的人参皂苷72 h下均可使细胞存活率降低(P<0.05).人参皂苷Rg5作用HepG2细胞24、48和72 h后的IC50值分别为138.60、91.12和46.92μmol/L.与对照(0μmol/L)组相比,40、80和160μmol/L处理组中侵袭细胞数[(57.38±3.65)个,(35.26±2.15)个,(32.48±2.23)个比(82.55±6.02)个]、迁移细胞数[(94.25±6.12)个,(51.57±3.15)个,(48.73±3.26)个比(137.62±8.83)个]、细胞在S期的百分比[(30.06±1.75)％,(23.32±1.51)％,(21.95±1.13)％比(36.85±2.26)％]和p-AKT[(0.61±0.04),(0.32±0.03),(0.28±0.03)比(0.79±0.06)]、cyclin D1、MMP-9、Bcl-2蛋白的表达水平均明显降低(P<0.05),而细胞凋亡率[(12.58±2.12)％,(28.35±2.26)％,(25.27±3.23)％比(5.06±1.25)％]、细胞在G0/G1期的百分比[(52.85±3.42)％,(64.54±4.03)％,(67.02±4.15)％比(44.16±3.08)％]均明显升高(P<0.05).结论 人参皂苷Rg5可抑制肝癌HepG2细胞增殖、侵袭和迁移并诱导细胞周期阻滞和凋亡,其作用机制可能与抑制AKT信号通路活化有关.     

Malathion‐induced oxidative stress,cytotoxicity, and genotoxicity in human liver carcinoma (HepG2) cells

Malathion is an organophosphate pesticide that is known for its high toxicity to insects and low to moderate potency to humans and other mammals. Its toxicity has been associated with the inhibition of acetylcholinesterase activity, leading to the interference with the transmission of nerve impulse, accumulation of acetylcholine at synaptic junctions, and subsequent induction of adverse health effects including headache, dizziness, nausea, vomiting, bradycardia, and miosis. Oxidative stress (OS) has been reported as a possible mechanism of malathion toxicity in humans. Hence, the aim of this study was to examine the role of OS in malathion‐induced cytotoxicity and genotoxicity. To achieve this goal, MTT, lipid peroxidation, and single cell gel electrophoresis (Comet) assays were performed, respectively, to evaluate the levels of cell viability, malondialdehyde (MDA) production, and DNA damage in human liver carcinoma (HepG₂) cells. Study results indicated that malathion is mitogenic at lower levels of exposure, and cytotoxic at higher levels of exposure. Upon 48 h of exposure, the average percentages of cell viability were 100% ± 11%, 117% ± 15%, 86% ± 15%, 35% ± 9%, and 27% ± 7% for 0, 6, 12, 18, and 24 mM, respectively. In the lipid peroxidation assay, the concentrations of MDA produced were 12.55 ± 0.16, 20.65 ± 0.27, 31.1 ± 0.40, 34.75 ± 0.45, and 15.1 ± 0.20 μM in 0, 6, 12, 18, and 24 mM malathion, respectively. The Comet assay showed a significant increase in DNA damage at the 24 mM malathion exposure. Taken together, our results indicate that malathion exposure at higher concentrations induces cytotoxic and genotoxic effects in HepG₂ cells, and its toxicity may be mediated through OS as evidenced by a significant production of MDA, an end product of lipid peroxidation. © 2009 Wiley Periodicals, Inc. Environ Toxicol 2010.     

Comparative genotoxicity of nanosilver in human liver HepG2 and colon Caco2 cells evaluated by a flow cytometric in vitro micronucleus assay

Two widely used in vitro cell culture models, human liver HepG2 cells and human colon Caco2 cells, and flow cytometry techniques were evaluated as tools for rapid screening of potential genotoxicity of food‐related nanosilver. Comparative genotoxic potential of 20 nm silver was evaluated in HepG2 and Caco2 cell cultures by a flow cytometric‐based in vitro micronucleus assay. The nanosilver, characterized by the dynamic light scattering, transmission electron microscopy and inductively coupled plasma–mass spectrometry analysis, showed no agglomeration of the silver nanoparticles. The inductively coupled plasma–mass spectrometry and transmission electron microscopy analysis demonstrated the uptake of 20 nm silver by both cell types. The 20 nm silver exposure of HepG2 cells increased the concentration‐dependent micronucleus formation sevenfold at 10 µg ml^–1 concentration in attached cell conditions and 1.3‐fold in cell suspension conditions compared to the vehicle controls. However, compared to the vehicle controls, the 20 nm silver exposure of Caco2 cells increased the micronucleus formation 1.2‐fold at a concentration of 10 µg ml^–1 both in the attached cell conditions as well as in the cell suspension conditions. Our results of flow cytometric in vitro micronucleus assay appear to suggest that the HepG2 cells are more susceptible to the nanosilver‐induced micronucleus formation than the Caco2 cells compared to the vehicle controls. However, our results also suggest that the widely used in vitro models, HepG2 and Caco2 cells and the flow cytometric in vitro micronucleus assay are valuable tools for the rapid screening of genotoxic potential of nanosilver and deserve more careful evaluation. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.     

大蒜辣素对HepG2肝癌细胞增殖的抑制作用

目的:研究大蒜辣素(Allicin)对肝癌HepG2细胞增殖的影响。方法:采用高效液相色谱法提纯Allicin,运用细胞计数试剂盒(Cell counting kit-8,CCK-8)研究Allicin对HepG2细胞增殖的影响,运用流式细胞仪研究其对细胞凋亡、DNA代谢的影响,运用Western blot研究其对细胞凋亡基因表达的影响。结果:Allicin经HPLC法提纯后其纯度达到99%;Allicin能抑制HepG2细胞的增殖,导致细胞大量凋亡及死亡,凋亡率达到8.67%±3.2%,死亡率达到70.38%±1.8%;也导致细胞DNA代谢发生紊乱,使大部分细胞处于DNA合成的G0/G1期并使进入S期细胞含量减少,延缓细胞增殖。Western blot实验结果表明,Allicin能导致细胞凋亡相关蛋白大量表达。结论:Allicin能抑制肝癌细胞的增殖,导致细胞大量死亡并引发细胞凋亡,并引起细胞DNA代谢发生紊乱,细胞大部分被阻滞在DNA合成的G0/G1期,Western blot实验结果表明,细胞凋亡基因相关蛋白Bax大量表达,而Bcl-2表达降低。     

Enniatin A1, enniatin B1 and beauvericin on HepG2: Evaluation of toxic effects

Hepatotoxicity of three Fusarium mycotoxins, beauvericin (BEA) and two enniatins (ENNs) ENN A1 and ENN B1, in hepatocarcinoma cells (HepG2) were evaluated and compared. Concentrations used were 1.5 and 3 μM at 24, 48 and 72 h for each mycotoxin. Flow cytometry was used to examine enniatins effects on cell proliferation, to characterize the cell cycle phase where the cells blocked and to study the mitochondria role in ENNs-induced apoptosis. ENN B1 treated cells showed a time dependent G1 blockade at both concentrations used. ENN A1 and BEA decreased the apoptotic-necrotic percentage of cells comparing to control and disrupted the MMP as observed by TMRM and ToPro-3 fluorochromes signal. It is proposed a decreasing mycotoxin order by number of effects as follows: BEA > ENN B1 > ENN A1, with 47, 20 and 16%, respectively out of all situations compared.     

甲基莲心碱对HepG2细胞增殖及凋亡的影响

摘 要 目的：研究甲基莲心碱对人肝癌HepG2细胞增殖及凋亡的影响。方法: 采用CCK 8法观察甲基莲心碱对人肝癌细胞HepG2细胞生长增殖的影响;Hoechst33258染色观察甲基莲心碱作用HepG2细胞后细胞形态的变化;测定乳酸脱氢酶 (LDH)释放率观察HepG2细胞受损程度;Annexin V PI双染测定甲基莲心碱对HepG2细胞凋亡率的影响;PI/RNase单染检测不同浓度的甲基莲心碱对其凋亡周期的影响。结果: 甲基莲心碱对体外培养的人肝癌HepG2细胞的生长具有抑制作用,且呈剂量、时间依赖性;细胞膜的受损程度随着药物剂量的增大逐步提高;Hoechst33258及流式结果表示,甲基莲心碱可使HepG2细胞阻滞于G0/G1期,细胞凋亡率随药物浓度的增大亦呈增长趋势。结论: 甲基莲心碱可显著抑制肝癌HepG2细胞的生长增殖,并在一定的范围内呈剂量、时间依赖性,诱导其阻滞于G0/G1期,发生晚期凋亡。     

澳洲茄边碱对肝癌 HepG2细胞增殖及凋亡的影响

目的：探讨澳洲茄边碱（SM ）对 HepG2细胞增殖、凋亡的影响及其可能作用机制。方法用不同浓度SM 5、10、15和20μg／ml分别处理 HepG2细胞3、6、12和24 h ,并设不加药的对照组。采用MTT法检测 HepG2细胞增殖,DAPI染色法观察细胞核形态的变化,流式细胞术检测细胞凋亡和周期,Western blot法检测B细胞淋巴瘤‐白血病2（Bcl‐2）、Bcl相关X蛋白（Bax）、半胱天冬氨酸蛋白酶3（Caspase‐3）及Ki67的蛋白表达。结果与对照组相比,SM 呈剂量依赖性地抑制HepG2细胞增殖,促进HepG2细胞凋亡,将细胞周期阻滞于G2／M期,并且上调Bax和Caspase‐3蛋白表达,下调Bcl‐2和Ki67蛋白表达（P＜0．05或P＜0．01）。结论 SM 能有效抑制 HepG2细胞的增殖,促进细胞凋亡的发生;SM上调Bax和Caspase‐3表达,下调Bcl‐2和Ki67表达,细胞周期阻滞于G2／M期可能是其发挥上述作用的机制。