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排序方式: 共有1962条查询结果,搜索用时 15 毫秒
1.
目的:研究姜黄素和索拉非尼联合应用对人肾癌786-O 细胞株增殖的影响。方法采用 MTT 法观察姜黄素和索拉非尼对人肾癌细胞786-O 细胞株的抑制作用。结果姜黄素及索拉非尼能抑制人肾癌786-O 细胞株的增殖,并呈浓度及时间依赖性,两者作用人肾癌786-O 细胞株48 h 的半数抑制浓度( IC50)分别为29.2μmol/ L、6.5μmol/ L。姜黄素6.25μmol/ L、12.5μmol/ L、25μmol/ L、50μmol/ L 与索拉非尼1.5μmol/ L、3μmol/ L、6μmol/ L、12μmol/ L、联合24 h、48 h、72 h 的抑制率显著高于单用索拉非尼、姜黄素组( P ﹤0.05)。结论姜黄素在体外对人肾癌786-O 细胞株的增殖有明显的抑制作用,能提高索拉非尼对人肾癌786-O 细胞株的敏感性。 相似文献
2.
Flavia Girolami Andrea Barbarossa Paola Badino Shiva Ghadiri Damiano Cavallini Anna Zaghini Carlo Nebbia 《Toxins》2022,14(7)
Due to the climatic change, an increase in aflatoxin B1 (AFB1) maize contamination has been reported in Europe. As an alternative to mineral binders, natural phytogenic compounds are increasingly used to counteract the negative effects of AFB1 in farm animals. In cows, even low dietary AFB1 concentrations may result in the milk excretion of the genotoxic carcinogen metabolite aflatoxin M1 (AFM1). In this study, we tested the ability of dietary turmeric powder (TP), an extract from Curcuma longa (CL) rich in curcumin and curcuminoids, in reducing AFM1 mammary excretion in Holstein–Friesian cows. Both active principles are reported to inhibit AFM1 hepatic synthesis and interact with drug transporters involved in AFB1 absorption and excretion. A crossover design was applied to two groups of cows (n = 4 each) with a 4-day washout. Animals received a diet contaminated with low AFB1 levels (5 ± 1 µg/kg) for 10 days ± TP supplementation (20 g/head/day). TP treatment had no impact on milk yield, milk composition or somatic cell count. Despite a tendency toward a lower average AFM1 milk content in the last four days of the treatment (below EU limits), no statistically significant differences with the AFB1 group occurred. Since the bioavailability of TP active principles may be a major issue, further investigations with different CL preparations are warranted. 相似文献
3.
Nidhi Bharal Agarwal Seema Jain Dheeraj Nagpal Nitin Kumar Agarwal Pramod K. Mediratta Krishna K. Sharma 《Fundamental & clinical pharmacology》2013,27(2):169-172
Contemporary research indicates promising anticonvulsant effect of curcumin. However, its poor oral bioavailability is a major hindrance toward its pharmacological action. Thus, this study was carried out to evaluate the acute effect of liposome‐entrapped curcumin on increasing current electroshock seizures (ICES) test, pentylenetetrazole (PTZ)‐induced seizures, and status epilepticus in mice. Liposome‐entrapped curcumin in doses 25 and 50 mg/kg demonstrated significant increase in seizure threshold current and latency to myoclonic and generalized seizures in ICES test and PTZ‐induced seizures, respectively. Similarly, liposomal‐entrapped curcumin also increased the latency to the onset and decreased the duration of seizures during status epilepticus in mice. To conclude, liposomal‐entrapped curcumin possesses anticonvulsant activity against status epilepticus in mice. 相似文献
4.
目的:研究姜黄素对雄激素非依赖性前列腺癌细胞株PC-3细胞体外作用及其对血管内皮生长因子(VEGF)表达的影响,探讨其抗肿瘤的作用机制。方法:分别用0、6.25、12.5、25、50μmol/L浓度的姜黄素作用于PC-3细胞,12、24、36、48、72、96h后台盼蓝拒染法、四甲基偶氮唑蓝(MTT)法检测细胞生长活性;24h后流式细胞仪测定细胞周期及凋亡的变化,透射电镜观察细胞超微结构变化;半定量RT-PCR法检测PC-3细胞内VEGF mRNA的表达;ELISA检测细胞上清液中VEGF浓度。结果:姜黄素能显著抑制PC-3细胞的增殖,呈剂量与时间依赖性,不同浓度姜黄素组之间及不同时间组之间差异均有统计学意义(P〈0.01)。不同浓度姜黄素诱导PC-3细胞出现剂量依赖性G2/M期阻滞(P〈0.01),且各浓度组凋亡细胞比例均显著高于空白对照组(P〈0.01),差异有统计学意义;姜黄素作用24h后PC-3细胞出现凋亡的形态学改变;PC-3细胞内VEGF mRNA的表达和细胞上清液中VEGF呈剂量依赖性降低。结论:姜黄素能显著抑制体外PC-3细胞的生长,并促进其G2/M期阻滞和凋亡,VEGF mRNA及蛋白的表达也明显降低,可能是其抑制肿瘤和血管生长的机制之一。 相似文献
5.
目的 探讨姜黄素对大鼠肾草酸钙结晶肾损伤的影响及可能机制。 方法 40只C57BL/6大鼠随机分为5组:模型组(乙醛酸盐100 mg·kg-1·d-1)、不同剂量姜黄素(20,40,60 mg·kg-1·d-1)干预组和空白对照组。干预4周后检测各组大鼠的血、尿生化指标,肾脏结晶,大鼠肾脏丙二醛(MDA)含量和血红素加氧酶-1(HO-1)活性等指标; Western-blot检测各组大鼠肾组织中的核因子E2相关因子-2(NRF-2)和HO-1蛋白的表达含量。 结果 模型组大鼠的尿离子钙和尿草酸浓度分别为(3.37±0.13)和(2.50±0.05)mmol/L,相较于空白对照组大鼠[(2.27±0.17)和(2.04±0.05)mmol/L]显著升高(P<0.05); 模型组大鼠血清肌酐(SCr)水平、肾脏MDA含量、肾脏结晶及肾小管上皮细胞凋亡指数与空白对照组比较均显著升高(P<0.05)。随着姜黄素干预剂量的增加,大鼠的SCr和肾脏MDA含量呈下降趋势、肾脏结晶和肾小管上皮细胞凋亡指数有减轻趋势,与模型组比较,差别有统计学意义(P<0.05); 而肾脏HO-1活性程度、NRF-2蛋白和HO-1蛋白表达均呈升高趋势,与模型组比较,差别有统计学意义(P<0.05)。 结论 姜黄素可减轻大鼠草酸钙结晶引起的氧化应激肾损伤,减少草酸钙结晶形成,该作用可能与其上调NRF-2/HO-1蛋白表达有关。 相似文献
6.
本文对姜黄药材中总姜黄素的提取纯化方法进行了较深入的实验研究,采用可见-紫外分光光度法测定提取物中总姜黄素的含量。并对超声辅助提取法做了考察,采用正交实验法对超声提取法提取工艺条件进行优选,得到最佳的提取工艺条件为:姜黄粉碎成40目,75%的乙醇超声提取,提取时间为60min.,姜黄素的提取得率为4.96%。 相似文献
7.
为探讨姜黄素诱导急性髓系白血病(AML)原代细胞凋亡的作用及其机制,采用流式细胞术作细胞周期分析并检测Sub-G1峰值;SABC法检测Bcl-2家族Mcl-1、Bax和Bak蛋白表达.结果显示姜黄素不影响初治AML原代细胞细胞周期进展,但使Sub-G1峰值升高(P<0.05).在初治AML原代细胞,同样处理可下调Mcl-1表达、上调Bax和Bak表达,且结果有显著性差异.提示姜黄素可诱导初治AML患者原代细胞凋亡,&1-2基因家族成员参与姜黄素诱导白血病细胞凋亡. 相似文献
8.
姜黄素对人乳腺癌MCF-7细胞增殖抑制作用及机制研究 总被引:4,自引:0,他引:4
目的:探讨姜黄素对人乳腺癌MCF-7细胞增殖抑制、诱导凋亡作用及其分子作用机制。方法:MTT法检测姜黄素对MCF-7细胞的增殖抑制作用;流式细胞术PI单染法检测细胞周期;Annexin V/PI双染法检测细胞凋亡;RT-PCR法检测凋亡相关基因Bcl-2和Bax的mRNA表达水平。结果:姜黄素对MCF-7细胞生长有明显抑制作用,并呈剂量、时间依赖性;FCM结果显示姜黄素能使MCF-7细胞阻滞在G1/S期;Annexin V/PI双染法验证姜黄素可以诱导细胞凋亡;RT-PCR结果显示Bax mRNA水平明显上调,而Bcl-2的mRNA表达水平降低。结论:姜黄素对人乳腺癌MCF-7细胞增殖具有显著的抑制作用并可诱导细胞凋亡,其作用机制可能与其上调Bax基因表达水平的同时,下调Bcl-2基因表达水平,从而诱导细胞凋亡有关。 相似文献
9.
Background The function of peroxisome proliferator-activated receptor γ (PPARγ) in hepatic fibrogenesis remains largely unknown. Curcumin is a natural substance extracted form Curcuma Longa Linn and has a variety of pharmacological effects. In this study, the effects of curcumin on the proliferation, activation and apoptosis of rat hepatic stellate cells (HSCs) through PPARγ signaling were investigated.
Methods HSCs were isolated from the normal Sprague Dawley rats through in situ peffusion of the liver with Pronase E and density-gradient centrifugation with Nycodenz. Cells were treated with curcumin, troglitazone, salvianolic acid B or GW9662. The effect on HSCs proliferation was determined by MTT colorimetry. Total RNA was extracted by TRizol reagent and gene levels were determined by semi-quantitative RT-PCR. Total cellular and nuclear protein were isolated and separated by 10% sodium dodecy Isulfate polyacrylamide gel electrophoresis. Protein levels were determined by Western blot. Cell apoptosis was detected by Hoechst 33258 staining. PPARγ subcellular distribution was detected by immunofluorescent staining. The activities of MMP-2 and 9 were measured by Gelatin zymograph assay.
Results Curcumin suppressed HSCs proliferation in a dose-dependent manner. As HSCs underwent gradual activation with culture prolongation the PPARγ nuclear expression level decreased. Curcumin up-regulated PPARγ expression and significantly inhibited the production of a-SMA and collagen Ⅰ. PPARγ is expressed in the cytoplasm and nucleus and is evenly distributed in HSCs, but accumulated in the nucleus of HSCs and disappeared from cytoplasm after curcumin treatment. Hoechst 33258 staining showed that curcumin induced the apoptosis of culture-activated HSCs and significantly increased pro-apoptotic Bax expression and reduced anti-apoptotic Bcl-2 expression. Cyclin D1 gene, activated NFKB p65 protein and TGFβR-Ⅰ protein expression were down-regulated significantly by curcumin. The activities of MMP-2 and MMP-9 were enhanced significantly by curcumin.
Conclusions Curcumin can inhibit the proliferation and activation of HSCs, induce the apoptosis of activated HSCs and enhance the activities of MMP-2 and MMP-9. The effects of curcumin are mediated through activating the PPARγ sianal transduction pathway and associated with PPARγ nuclear translocation/redistribution. 相似文献
10.
目的研究姜黄素对人肾癌786-O细胞体外生长及细胞周期的影响,为肾癌治疗提供理论依据。方法应用MTT比色法和流式细胞仪检测人肾癌786-O细胞增殖抑制率及细胞周期各时相的变化和凋亡率。结果姜黄素对人肾癌786-O细胞有抑制作用,存在剂量依赖(F=6207.813,P〈0.01)与时间依赖(F=1210.386,P〈0.01);流式细胞仪分析,G1期细胞增多,S期细胞减少,C2/M期细胞相对增多。结论姜黄素可以抑制人肾癌786-O细胞增殖,阻止G1期细胞向S期的进程,促进人肾癌786-O细胞凋亡。 相似文献