非那西丁在二乙基亚硝胺诱发肝癌大鼠的代谢

目的　①研究非那西丁在二乙基亚硝胺 (DEN)诱发肝癌大鼠中的代谢 ,以及其它评估肝脏功能指标的改变 ;②血浆结合型代谢产物含量改变对非那西丁试验的影响。方法　饮用DEN诱发大鼠肝癌 ,观察血液非那西丁及利多卡因代谢产物 ,白蛋白和胆红素含量 ,凝血酶原时间的改变 ;采用HPLC法测定血浆中非那西丁结合型和游离型代谢产物含量。结果　与正常对照组相比 ,DEN组大鼠肝脏出现多发性癌结节 ,肝 /体重比增加 3 3倍 ,血浆谷丙转氨酶、γ 谷氨酰转肽酶和碱性磷酸酶含量明显升高 ,但凝血酶原时间、血浆白蛋白、非那西丁和利多卡因代谢产物含量无明显改变。DEN组大鼠血浆非那西丁游离型代谢产物含量高于正常对照组 43 9% (P <0 0 1) ,但结合型 +游离型代谢产物总量无明显差别。结论　在DEN诱发肝癌大鼠 ,肝细胞严重受损 ,肝脏体积增大 ,非那西丁代谢等肝功能试验无明显改变。同时测定游离型及结合型代谢产物含量 ,才能正确反映肝脏的生物转化功能。     

NO供体对二乙基亚硝胺诱发大鼠肝癌的抑制作用

目的研究NO供体-新型偶氮鎓二醇盐衍生物(JS-K)对二乙基亚硝胺(DEN)诱发大鼠肝癌的抑制作用。方法 50只Wistar雄性大鼠随机分为对照组,模型组,阳性组,药物低、高剂量组。除对照组外,其余组腹腔注射DEN50 mg·kg~(-1)(10 m L·kg~(-1)),每周2次,4周后每周1次,阳性药物组腹腔注射氟尿嘧啶5 mg·kg~(-1)(10 m L·kg~(-1)),药物组按0.25和0.5 mg·kg~(-1)(5 m L·kg~(-1))尾静脉注射,每周2次,对照组腹腔注射生理盐水(10 m L·kg~(-1)),给药至第16周。观察肝外观;比色法检测总蛋白(TP)、白蛋白(Alb)、丙氨酸氨基转移酶(ALT)和天门冬氨酸氨基转移酶(AST)含量;ELISA检测甲胎蛋白(AFP)含量;HE染色观察肝组织病变程度;免疫组化检测PCNA和ERK水平;Western印迹检测Bcl-2、Bax和活化胱天蛋白酶3水平。结果模型组大鼠肝表面散在大小不等的灰白色结节,有明显的巨瘤块和坏死灶,药物组上述情况明显减轻。与模型组相比,药物组大鼠血清中TP和Alb含量升高,ALT,AST和AFP活性降低(P<0.01)。HE结果显示,与模型组相比,药物组肝小叶结构相对较好,细胞异型性明显减轻,细胞核变小,多核细胞明显减少。免疫组化结果显示,与模型组相比,药物组PCNA和ERK表达减少。Western印迹结果显示,JS-K引起Bcl-2表达下调,Bax和活化胱天蛋白酶3表达上调(P<0.01)。结论 NO供体JS-K对二乙基亚硝胺诱发大鼠肝癌具有抑制作用。     

海洛因滥用大鼠尿液同体纵向对照模型的代谢组学研究

目的:建立海洛因滥用大鼠尿液同体纵向对照模型的代谢组学研究模型,研究海洛因滥用与大鼠体内生物标记物特异性变化关系在研究海洛因依赖的潜在价值。方法:以雄性SD大鼠为实验动物,经尾静脉反复注射盐酸海洛因溶液建立大鼠海洛因依赖模型,收集给药前和停药成瘾后大鼠尿液,并用UPLC-MS分析尿液,经Mzmine2.1软件峰匹配和多种统计学分析,筛选出有差异性变化的海洛因滥用生物标记物。同时进行重复实验对结果进行验证。结果:停药后24 h大鼠出现戒断症状,经纳洛酮催促戒断实验证实大鼠已对海洛因形成依赖。给药前和停药后大鼠尿液数据经统计学分析存在分离现象,说明两组尿液中生物标记物间存在特异性差异。结论:大鼠对海洛因滥用形成依赖前后尿液中生物标记物存在差异,经统计学初步筛选出41个特异性的生物标记物,说明借助代谢组学技术研究尿液中生物标记物的特异性变化来推断机体是否对海洛因依赖具有一定的可行性。     

肝细胞性肝癌代谢组学研究进展

肝细胞性肝癌(HCC)是最常见的、发病率和死亡率较高的恶性肿瘤之一,严重危害了人类的健康。代谢组学能够将高通量、高分辨率的分析技术与生物信息学相整合,对生物代谢层面进行研究,为寻找早期诊断肝细胞性肝癌的生物标志物、探索HCC发生的机制提供独特的视角。本文对近年来肝细胞性肝癌代谢组学研究进展进行综述,为进一步深入研究提供参考。     

脾气虚证模型大鼠尿液的~1H-NMR代谢组学研究

目的建立脾气虚证大鼠模型,分析脾气虚证的代谢通路,探究内源性代谢产物变化与脾气虚证的关系。方法采用苦寒泻下、劳倦过度和饥饱失常复合因素方法建立并评价脾气虚证大鼠模型,检测其血清中肌酸磷酸激酶活性;对大鼠尿液进行~1H-NMR检测,以变化倍数(fold change,FC)>1.2,结合独立样本t检验(P<0.05)的统计学方法筛选脾气虚证模型组和对照组的差异代谢物,进行代谢通路分析与富集分析。结果脾气虚证模型建立成功;模型组的肌酸磷酸激酶活性低于对照组(P<0.05);从主成分分析(PCA)结果得出模型组和对照组的代谢产物得到明显区分;筛选出33种差异代谢物,主要参与的代谢通路涉及能量代谢、氨基酸代谢、核苷酸代谢,同时对肠道菌群存在干扰。结论脾气虚主要扰乱了大鼠的能量代谢通路(三羧酸循环、糖酵解、脂质氧化),抑制了供能作用,导致大鼠出现疲乏和体质量增长抑制的症状。     

苦参碱和氧化苦参碱对二乙基亚硝胺诱发大鼠肝癌作用的影响

目的　研究苦参碱和氧化苦参碱对二乙基亚硝胺诱发大鼠肝癌作用的影响。方法　采用二乙基亚硝胺法诱发大鼠肝癌 ,观察腹腔注射苦参碱 2 5mg·kg-1和氧化苦参碱10 5mg·kg-130d后 ,大鼠肝表面癌结节数、肝 /体重比和血清中丙氨酸氨基转移酶 (ALT)、γ 谷氨酰转肽酶 (γ GT)、碱性磷酸酶 (ALP)的变化。结果　氧化苦参碱组大鼠肝表面癌结节数、肝 /体重比和血清ALT、γ GT明显低于模型组 (P<0 0 5 ) ;苦参碱组大鼠肝表面癌结节数和血清γ GT明显低于模型组 (P <0 0 5 )。结论　苦参碱和氧化苦参碱 ,尤其是氧化苦参碱 ,不仅能保护肝细胞免受损伤 ,而且能抑制肿瘤细胞增长     

番茄红素对二乙基亚硝胺损伤大鼠肝脏的保护作用

番茄红素是一种具有鲜红颜色的天然类胡萝卜素,具有优越的生理活性,如淬灭单线态氧、清除自由基、诱导细胞间连接通讯和调控肿瘤增殖等。番茄红素能够减缓动脉粥样硬化,防止冠心病的发生[1],能提高肝脏抗氧化能力,使机体免受氧化损伤[2]。二乙基亚硝胺(diethylnitrosamine,DEN)     

二至丸干预大鼠急性酒精肝损伤的尿液代谢组学研究

目的：研究酒精致急性肝损伤模型大鼠尿液内源性代谢物的变化特点及二至丸对异常代谢的调节作用,寻找二至丸治疗急性酒精肝损伤的潜在代谢生物标志物,以探索二至丸对酒精性肝损伤的保护作用机制。方法：以白酒灌胃法建立急性酒精肝损伤大鼠模型,基于快速分离液相色谱串联四极杆飞行时间质谱（RRLC-Q-TOF/MS）技术分析空白组、模型组、二至丸给药组大鼠尿样代谢轨迹,通过单因素方差分析（ANOVA）结合正交偏最小方差判别分析（OPLS-DA）,研究各组之间的代谢物组差异。结果：初步鉴定出可能的10种潜在代谢生物标志物,这些内源性成分在二至丸给药组大鼠尿液中恢复明显。结论：二至丸可以使酒精性肝损伤大鼠尿液中一些代谢物水平得到不同程度的恢复,其治疗作用可能与4条相关代谢通路的调节有关。     

纳米铜经口染毒大鼠尿液的代谢组学研究

目的 研究纳米铜经口反复染毒大鼠尿液的代谢表型改变,探讨纳米铜的毒作用特征,并寻找早期损害的代谢标志物.方法 雄性Wistar大鼠42只,每组6只分别经口给予溶剂羟丙甲基纤维素(1% HPMC),微米铜(200mg/kg),纳米铜(50、100和200 mg/ks),连续染毒5 d,核磁共振(NMR)分析不同时点收集的24 h尿液,并作血液生化分析和肝肾组织病理学检查.结果 纳米铜200 mg/kg连续染毒5 d,大鼠血清丙氨酸转移酶、天冬氨酸转移酶、三酰甘油、总胆红素、总胆汁酸、肌酐和尿素氮均明显升高;肝细胞呈点状或局灶性坏死,肾小管上皮细胞弥漫性坏死;毒性明显重于其余处理组.尿液代谢组学分析表明纳米铜200 mg/kg染毒早期可诱导大鼠尿液中肌酐、牛磺酸和N-乙酰葡糖苷酶水平升高;染毒5 d,尿液中柠檬酸、乳酸和醋酸盐、糖、氨基酸和N-氧三甲胺水平明显升高,肌酐水平降低;纳米铜200 mg/kg组大鼠停止染毒一周,尿液代谢轨迹不能回到处理前状态.结论 肝脏和肾脏是纳米铜的靶器官,细胞能量代谢紊乱可能是纳米铜诱导肝肾损害过程中的重要事件,代谢组学分析可作为纳米材料在体毒性评价的技术平台之一.     

水飞蓟宾对二乙基亚硝胺诱导的鼠肝致癌作用的保护效应

目的 探讨水飞蓟宾对二乙基亚硝胺(DEN)诱导的鼠肝致癌作用的保护效应.方法 雄性Wistar鼠随机分为4组,分别饲以基础饮食或辅以500 ppm(500×10-6)或1 000 ppm(1 000×10-6)水飞蓟宾饮食,并在14 d后进行单次腹腔注射DEN,剂量100 mg/kg.各自组在DEN引入后24 h或2周被处死.收集肝组织样品,分析增殖细胞核抗原(PCNA),转化生长因子α(TGF-α)、P53、凋亡.同时进行分光光度计分析丙氨酸氨基转移酶(ALT)和天门冬氨酸氨基转移酶(AST).结果 1 000×10-6水飞蓟宾预处理组,鼠肝细胞的凋亡和P53、TGF-α、PCNA免疫反应性明显减少.所有DEN注射组均明显具有较高水平的血清转氨酶(AST和ALT).结论 水飞蓟宾在DEN诱导的鼠肝致癌作用起始阶段表现出抑制作用.     

Augmentation of diethylnitrosamine–induced early stages of rat hepatocarcinogenesis by 1,2-dimethylhydrazine

Diethylnitrosamine (DEN) and 1,2-dimethylhydrazine (DMH) are classical carcinogens used in experimental rodent carcinogenesis. However, the interaction effects of these carcinogens on biochemical and molecular changes during carcinogenesis have not been investigated. Therefore, the effect of DEN and DMH co-administration on preneoplastic lesion formation and its molecular mechanism in rats were determined. Triple intraperitoneal administrations of DEN were made before, during or after double subcutaneous injections of DMH. At week 8 of the experiment, the preneoplastic hepatic glutathione-S-transferase placental form (GST-P) positive foci and colonic aberrant crypt foci (ACF) were analyzed. The combined treatment of these carcinogens increased toxicity to rats. Administration of DMH alone did not induce hepatic GST-P positive foci, while co-treatment with DMH enhanced hepatic GST-P positive foci formation. However, DEN did not influence the size or number of colonic ACF. The treatment with DMH alone induced CYP2E1 and P450 reductase, demonstrating that DMH enhanced DEN metabolism in DEN- and DMH-treated rats. These findings were related to increases in hepatic O⁶-methylguanine DNA adducts and hepatotoxicity, which are associated with the induction of cell proliferation and liver cancer development. DEN-induced early stages of rat hepatocarcinogenesis were synergistically promoted by DMH via metabolic enzyme induction leading to enhanced DNA mutation and hepatocarcinogenicity.     

神经酰胺诱导肝肿瘤Bel7402细胞凋亡(英文)

目的:了解神经酰胺信号转导在肝肿瘤细胞中的生物学意义。方法:MTT法、荧光染色、流式细胞术、琼脂糖凝胶电泳、Western blot。结果:神经酰胺对Bel7402细胞生长抑制的IC_(50)值为14.28μmol·L~(-1)。细胞核浓缩,荧光明显增强;DNA呈现典型“梯型”变化;p53蛋白表达呈下降趋势;Bcl-2蛋白表达明显降低;Bax蛋白表达无明显改变。结论:神经酰胺诱导肝肿瘤细胞凋亡,与Bcl-2表达下调有关。     

新型钌多吡啶配合物诱导肝癌细胞凋亡的机制研究

目的探讨钌多吡啶配合物的体内外抗肝癌活性及其作用机制。方法 MTT法筛选出高效低毒的钌配合物2b;流式细胞术分析其对细胞周期的影响;Western blot法检测p53和p21蛋白的表达水平;荷瘤裸鼠实验评价该配合物的体内抗肿瘤活性。结果钌多吡啶配合物对多种人肝癌细胞株的生长有抑制作用,其中配合物2b对肝癌细胞Hep3B的作用最明显,IC50为12.1μmol·L~(-1)。2b可以有效地诱导Hep 3B细胞凋亡,使细胞内出现了DNA断裂,染色质固缩及subG1凋亡峰的出现。同时,2b能够激活caspase-9和caspase-3,促使p53蛋白磷酸化,提高p53总蛋白和p21蛋白的表达水平。体内实验表明,配合物2b对裸鼠肿瘤的生长有明显的抑制作用。结论钌多吡啶配合物在体内外模型中均具有良好的抗肝癌活性,通过诱导肿瘤细胞凋亡而抑制其增殖。     

Maté attenuates DNA damage and carcinogenesis induced by diethylnitrosamine and thermal injury in rat esophagus

Drinking hot maté has been associated with risk for esophageal cancer in South America. Thus, the aims of this study were to evaluate the modifying effects of maté intake on DNA damage and esophageal carcinogenesis induced by diethylnitrosamine (DEN) and thermal injury (TI) in male Wistar rats. At the initiation phase of carcinogenesis, rats were treated with DEN (8 × 80 mg/kg) and submitted to TI (water at 65 °C, 1 ml/rat, instilled into the esophagus). Concomitantly, the animals received maté (2.0% w/v) for 8 weeks. Samples of peripheral blood were collected 4 h after the last DEN application for DNA damage analysis. At weeks 8 and 20, samples from esophagus and liver were also collected for histological and immunohistochemical analysis. Maté significantly decreased DNA damage in leukocytes, cell proliferation rates in both esophagus and liver and the number of preneoplastic liver lesions from DEN/TI-treated animals at week 8. A significant lower incidence of esophageal papillomas and liver adenomas and tumor multiplicity was observed in the animals previously treated with maté at week 20. Thus, maté presented protective effects against DNA damage and esophageal and liver carcinogenesis induced by DEN.     

Dynamic changes in DNA methylation during multistep rat lung carcinogenesis induced by 3-methylcholanthrene and diethylnitrosamine

3-methylcholanthrene (MCA) and diethylnitrosamine (DEN) are typical genotoxic carcinogens that can induce tumors in a variety of human and rodent tissues. However, the epigenetic mechanisms underlying their tumorigenesis are unclear. In this study we used a MCA/DEN-induced multistep lung carcinogenesis rat model to study the evolution of alterations in DNA methylation. Rats were treated with a single dose of MCA and DEN in iodized oil by left intra-bronchial instillation. The animals were killed on days 15, 35, 55, 65 and 75 and samples of various pathological phases during carcinogenesis were obtained on these days. The status of global methylation was analyzed for each sample using a monoclonal antibody specific for 5-methycytosine (5-mC) and quantified by image analysis software. We found that the degree of global methylation was, in general, higher in basal cells compared to luminal cells of normal, precancerous and tumor tissues. The combined 5-mC scores of different types of tissues decreased gradually during the progression of carcinogenesis. We also used methylation-sensitive arbitrarily primed PCR (MS-AP-PCR) to screen a total of eight differentially methylated DNA fragments in both precancerous and tumor tissues isolated using laser capture microdissection (LCM), and observed that both unique hypomethylation and hypermethylation fragments coexist after exposure to genotoxic carcinogens. Remarkably, epigenetic alterations in p16 (CDKN2A), but not in p15 (CDKN2B), were observed, and these correlated with the presence of pathologic lung lesions and loss of p16 protein expression. Moreover, defective expression of p16 in methylated primary tumor cell lines recovered markedly after treated with 5-aza-2′-deoxycytidine (5-aza-dC). These results suggest that DNA methylation alterations are an early event in tumorigenesis and play an important role during MCA/DEN-induced multistep rat lung carcinogenesis.     

Tamoxifen induces hepatocellular carcinoma in rat liver: A 1-year study with two antiestrogens

The effects of equimolar doses of the triphenylethylene antiestrogens tamoxifen and toremifene on female Sprague-Dawley rat liver were studied in a 52-week toxicity study which included a 13-week recovery period. Liver tumors were found in four out of five rats at the highest dose level of tamoxifen (45 mg/kg per day) after 52 weeks of dosing, and these appeared to be hepatocellular carcinomas in three rats. After the 13-week recovery period all surviving rats in the highest tamoxifen dose group had large liver tumors (diameter up to 2 cm) which appeared to be hepatocellular carcinomas in five out of six rats. No tumor was observed in the toremifene-treated rats (48 mg/kg per day) either after 52 weeks of dosing or after the recovery period. Electron microscopic morphometric analysis after 52 weeks of dosing revealed that at the tamoxifen high dose level, the volume densities of the peroxisomes, mitochondria, and residual bodies were elevated in the nonneoplastic hepatocytes of the rats. In the neoplastic hepatocytes of the tamoxifen-treated rats the volume density of nuclei was slightly elevated. The slight proliferation of peroxisomes and mitochondria might be related to tumor development in the tamoxifen treated rats.