重组人P53融合蛋白抗肝癌细胞的实验研究

研究蛋白传导域(PTD)与人野生型P53(WtP53)融合表达的P53融合蛋白PTD-P53对HepG2的增殖抑制和凋亡的影响.用PTD-P53处理HepG2后,采用MTT法分析处理后细胞的生长增殖情况,流式细胞术(FCM)分析处理后细胞周期变化及脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(TUNEL)检测细胞凋亡情况.PTD-P53对:HepG2的生长有明显抑制作用.细胞周期也出现阻滞现象,细胞凋亡明显增加.PTD-P53有一定的抗肝癌细胞作用.     

Antiproliferative activity and standardization of Tecomella undulata bark extract on K562 cells

Ethnopharmacological relevance

The bark of Tecomella undulata is primarily used in the treatment of syphilis, painful swellings and cancer by traditional healers. Also, it is claimed to be useful in treating urinary discharges, enlargement of spleen, leucorrhoea, leukoderma, tumors, liver disorders, gonorrhea, gout and promotes wound healing in Indian traditional system of medicine.

Aim

To establish a scientific validation for the antitumor effects of Tecomella undulata bark and explore the mechanistic pathway in chronic myeloid leukemia cell line, K562. The study was further extended to standardize the extract using quercetin as biomarker.

Methods

Induction of apoptosis by chloroform extract of Tecomella undulata bark (CTUB) was determined by MTT, Annexin V and caspase activation assays. The cell cycle analysis was done by flow cytometer and nuclear staining by DAPI. The standardization of the extract was performed through reverse phase-HPLC method under PDA detection.

Result

Results clearly showed the induction of apoptosis by CTUB in K562 cells. The effect was found to be dose dependent, having IC₅₀ of 30 μg/ml with activation of FAS, FADD, caspase 8, caspase 3/7 and fragmentation of DNA. The bioactive CTUB was determined to possess 0.03% (w/w) of quercetin.

Conclusion

The investigation clearly demonstrated the potential antitumor effect of CTUB, thereby validating the traditional claim. Quercetin, known to have anticancer activity is being reported and quantified for the first time from the bark of Tecomella undulata.     

Antiviral activities of extracts isolated from Terminalis chebula Retz., Sanguisorba officinalis L., Rubus coreanus Miq. and Rheum palmatum L. against hepatitis B virus.

The antiviral effects of aqueous extracts of Terminalis chebula Retz., Sanguisorba officinalis L., Rubus coreanus Miq. and Rheum palmatum L. were examined by a cell culture system using a hepatitis B virus (HBV) producing cell line, HepG2 2.2.15. The extracts were assayed for the inhibition of HBV multiplication by measurement of HBV DNA and surface antigen (HBsAg) levels in the extracellular medium of HepG2 2.2.15 cells after an 8-day treatment. All extracts decreased the levels of extracellular HBV virion DNA at concentrations ranging from 64 to 128 microg/mL and inhibited the secretion of HBsAg dose dependently. Of the four tested plants, Terminalis chebula exhibited the most prominent anti-HBV activities.     

沙立度胺单独及联合多柔比星对人肝癌细胞株HepG2中生存素表达的影响

目的：观察沙立度胺单独及联合多柔比星对人肝癌细胞株HepG2中生存素（Survivin）表达的影响。方法：常规培养人肝癌细胞株HepG2随机分成4组：空白对照组；多柔比星组（1．0mg／L）；沙立度胺组（50、100、200、400mg／mL，4个对半稀释质量浓度）；联合用药组：沙立度胺（200mg／mL）＋多柔比星（1．0mg／L）。分别对HepG2细胞作用12、24、48、72h后，应用免疫组织化学法观察对Survivin表达的影响。结果：沙立度胺单独及联合多柔比星作用于HepG2细胞可下调Survivin表达，单药沙立度胺以200mg／L作用48h效果最为明显，联合用药组下调Survivin表达优于其余各组，差异有统计学意义（P〈0．05）。结论：沙立度胺可下调人肝癌细胞株HepG2Survivin的表达，且与多柔比星有协同作用，可能是沙立度胺抗肿瘤机制之一。     

两面针提取物抗肝癌谱-效关系研究

目的 研究两面针药材提取物HPLC指纹图谱与抗肝癌活性之间的关系。方法 以人肝癌细胞株HepG2为药效模型,采用MTT法测定33批不同产地两面针药材提取物的抗肝癌活性,采用逐步后退法将量化特征峰面积与MTT法测得两面针提取物抗肿瘤活性的结果结合,构建两面针药材提取物抗肝癌的谱效关系方程。结果 建立的两面针药材提取物HPLC指纹图谱相似度达到0.7以上,经相似度软件筛选出24个特征指纹峰,用逐步后退法拟合两面针药材提取物抗肝癌谱效关系方程,该方程具有统计学意义和实际意义,可较准确地预测两面针药材提取物的抗肝癌活性。结论 两面针药材提取物抗肝癌活性是多种成分协同、互补、制约相互作用的结果,根据方程可预测肿瘤细胞的敏感性。     

六月青总皂苷对HepG2.2.15细胞HBV复制的抑制作用

目的 观察六月青总皂z苷(the terpenoids of Liuyueqing,TLYQ)体外抗乙型肝炎病毒(HBV)的作用.方法 采用血清药理学方法 ,在HBV的体外细胞培养系统中(2.2.15细胞)进行TLYQ抗HBV作用观察.结果 TLYQ含药血清在HepG2.2.15细胞培养中可有效地抑制细胞HBV DNA的复制,其作用呈明显的量效和时效反应关系.结论 TLYQ在体外能明显抑制HBV,是六月青主要活性成分之一.     

槐果碱体外对HepG2.2.15细胞分泌HBsAg HBeAg的影响

目的:探讨槐果碱的体外抗乙型肝炎病毒作用。方法:采用HepG2.2.15细胞模型进行体外培养,给予不同浓度槐果碱,以拉米夫定作阳性对照,作用9天后检测上清液中HBsAg、HBeAg的分泌,观察药物对HepG2.2.15细胞分泌HBV病毒抗原的影响,同时以MTT法检测药物在体外对HepG2.2.15细胞的生长抑制作用,从而评价药物的抗HBV作用。结果:药物作用9天后,槐果碱对HepG2.2.15细胞的50%生长抑制率(TC50)为0.002M,对HepG2.2.15细胞分泌HBsAg的50%抑制率(IC50)为4.9uM,其治疗指数(TI=TC50/IC50)为408.16;而拉米夫定对HepG2.2.15细胞分泌HBsAg的抑制率在所选浓度范围内均低于50%。槐果碱对HepG2.2.15细胞分泌HBeAg的抑制率在所选浓度范围内均低于50%,但明显优于拉米夫定对HepG2.2.15细胞分泌HBeAg的抑制率。结论:槐果碱在体外具有显著的抑制HepG2.2.15细胞分泌HBsAg、HBeAg的作用,是一个高效低毒的抗乙肝病毒的有效药物。     

荔枝核总皂苷体外抗乙型肝炎病毒的作用

0 引言 我国属乙型病毒性肝炎高流行区,2004年中国疾病预防控制中心调查显示我国HBsAg感染率高达9．09％．目前,尚没有理想的治疗慢性乙型肝炎的药物．我国有数千年应用中草药治疗疾病的传统和经验,从中已发现了不少抗乙型肝炎病毒（HBV）的药物．荔枝核是无患子科植物荔枝（Litchi chinensis Sonn）的成熟种子,又名荔仁或荔核,味甘、微苦,归肝、肾经,具有行气散结、祛寒止痛的功效．其化学成分包括皂苷、蒜质和脂肪酸等多种物质．研究发现,荔枝核黄酮类提取物对乙肝病毒HBsAg,HBeAg以及HBVDNA有明显的抑制作用．但荔枝核皂苷是否具有抑制HBV的作用,目前尚未见文献报道．我们采用HepG2．2．15细胞为靶细胞,观察不同浓度荔枝核总皂苷体外对HBV的抑制作用．     

黑树莓花色苷对HepG2细胞胰岛素抵抗作用研究

目的 探讨黑树莓花色苷（ROAs）对HepG2细胞胰岛素抵抗（IR）的影响。方法 MTT法检测3.75、7.50、15.00、30.00、60.00 μg·mL^-1的ROAs作用24、48 h对HepG2细胞存活率的影响,确定ROAs的给药条件;含高糖（4.5 g·L^-1）、高胰岛素（1.0×10^-7、1.0×10^-6、1.0×10^-5、1.0×10^-4 mol·L^-1）的DMEM培养基培养HepG2细胞24或48 h,采用葡萄糖氧化试剂盒检测每孔上清液中葡萄糖水平,计算每孔细胞葡萄糖消耗量,确定IR细胞模型的建立条件;HepG2细胞分为对照组、模型组、二甲双胍（阳性药,0.01 mol·L^-1）组和ROAs（7.5、15.0、25.0、30.0 μg·mL^-1）组,除对照组外,各组细胞培养24 h后建立IR模型,模型建立后药物处理24 h,试剂盒法检测葡萄糖消耗量,HE染色评价细胞形态学改变。结果 选择7.5、15.0、25.0、30.0 μg·mL^-1作为ROAs后续给药质量浓度,给药时间为24 h;HepG2细胞IR模型建立条件为：含高糖（4.5 g·L^-1）、高胰岛素（1.0×10^-4 mol·L^-1）的DMEM培养基培养24 h。与对照组比较,模型组细胞葡萄糖的消耗量明显降低,具有统计学差异（P＜0.001）;与模型组比较,质量浓度为15.0、25.0、30.0 μg·mL^-1的ROAs组细胞葡萄糖消耗量均显著增加,具有统计学意义（P＜0.05、0.001）。与对照组比较,模型组细胞的形态不固定,细胞核圆形,胞浆不成型,脂滴明显增多;ROAs对HepG2细胞的胞浆形态有改善作用并且使脂滴明显减少。结论 ROAs能够改善高糖、高胰岛素诱导的HepG2细胞IR。     

Flow cytometric evaluation of the contribution of ionic silver to genotoxic potential of nanosilver in human liver HepG2 and colon Caco2 cells

Exposure to nanosilver found in food‐ and cosmetics‐related consumer products is of public concern because of the lack of information about its safety. In this study, two widely used in vitro cell culture models, human liver HepG2 and colon Caco2 cells, and the flow cytometric micronucleus (FCMN) assay were evaluated as tools for rapid predictive screening of the potential genotoxicity of nanosilver. Recently, we reported the genotoxicity of 20 nm nanosilver using these systems. In the current study presented here, we tested the hypothesis that the nanoparticle size and cell types were critical determinants of its genotoxicity. To test this hypothesis, we used the FCMN assay to evaluate the genotoxic potential of 50 nm nanosilver of the same shape, composition, surface charge and obtained from the same commercial source using the same experimental conditions and in vitro models (HepG2 and Caco2) as previously tested for the 20 nm silver. Results of our study show that up to the concentrations tested in these cultured cell test systems, the smaller (20 nm) nanoparticle is genotoxic to both the cell types by inducing micronucleus (MN). However, the larger (50 nm) nanosilver induces MN only in HepG2 cells, but not in Caco2 cells. Also in this study, we evaluated the contribution of ionic silver to the genotoxic potential of nanosilver using silver acetate as the representative ionic silver. The MN frequencies in HepG2 and Caco2 cells exposed to the ionic silver in the concentration range tested are not statistically significant from the control values except at the top concentrations for both the cell types. Therefore, our results indicate that the ionic silver may not contribute to the MN‐forming ability of nanosilver in HepG2 and Caco2 cells. Also our results suggest that the HepG2 and Caco2 cell cultures and the FCMN assay are useful tools for rapid predictive screening of a genotoxic potential of food‐ and cosmetics‐related chemicals including nanosilver. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.