目的:研究维生素E琥珀酸酯(vitamin E succinate,VES)是否可通过氧化应激来诱导胃癌细胞凋亡及其可能机制。方法:分别用5、10和20μg/ml的VES处理胃癌SGC-7901细胞24h,同时设阴性对照组和甘露醇(活性氧抑制剂)预处理组。通过流式细胞技...目的:研究维生素E琥珀酸酯(vitamin E succinate,VES)是否可通过氧化应激来诱导胃癌细胞凋亡及其可能机制。方法:分别用5、10和20μg/ml的VES处理胃癌SGC-7901细胞24h,同时设阴性对照组和甘露醇(活性氧抑制剂)预处理组。通过流式细胞技术、共聚焦技术和Western blot方法,检测了VES诱导SGC-7901细胞线粒体氧化损伤及细胞凋亡的情况,用相应的检测试剂盒检测细胞内活性氧和Ca2+含量变化情况。结果:不同浓度的VES对SGC-7901细胞均有诱导凋亡的作用。表现为随VES浓度的增加,SGC-7901细胞凋亡数量呈现增加的趋势,且SGC_7901细胞内活性氧含量及钙离子水平呈现增加的趋势,而线粒体膜电位逐渐下降。活性氧抑制剂甘露醇(1mmol/L)对VES诱导的胃癌细胞凋亡,和细胞内活性氧、钙浓度的增高及膜电位的降低均有显著抑制作用(P<0.05)。随VES浓度的增加,SGC_7901细胞内Bax蛋白的表达呈现上升的趋势,而Bcl-2蛋白的表达呈现下降趋势。甘露醇可显著降低胃癌SGC-7901细胞Bax蛋白的表达水平,同时增加Bcl-2蛋白的表达(P<0.05)。结论:VES可显著促进胃癌细胞凋亡,并且随着VES剂量的增加,VES诱导胃癌细胞凋亡的作用越强。细胞内活性氧含量增加、细胞内钙超载所导致的线粒体氧化损伤作用可能是VES诱导细胞凋亡的机制之一。展开更多
A screening of commercially available lipases for the synthesis of vitamin E succinate showed that lipase from Candida rugosa presented the highest yield. The synthesis of vitamin E succinate in organic solvents with ...A screening of commercially available lipases for the synthesis of vitamin E succinate showed that lipase from Candida rugosa presented the highest yield. The synthesis of vitamin E succinate in organic solvents with dif- ferent lgP values ranging from -1.3 to 3.5 was investigated. Of particular interest was that dimethyl sulfoxide （DMSO） with the lowest lgP exhibited the highest yield among all the organic solvents used. It suggests that lgP is incapable of satisfactorily predicting the biocompatibility of organic solvents due to the complexity of enzymatic reaction with hydrophilic and hydrophobic substrates in organic solvent. Effects of different operating conditions, such as molar ratio of substrate, enzyme concentration, reaction temperature, mass transfer, and reaction time were also studied. Under the optimum conditions of 10 g/L enzyme, a stirring rate of 100 r/min, a substrate molar ratio of 5：1 at 55℃ for 18 h, a satisfactory yield（46.95%） was obtained. The developed method has a potential to be used for efficient enzymatic production of vitamin E succinate.展开更多
背景与目的:研究Bid在维生素E琥珀酸酯(vitamin E succinate,VES)诱导人胃癌SGC-7901细胞凋亡中的作用。材料与方法:在VES诱导SGC-7901细胞凋亡过程中,检测Bid蛋白的活化;用RNA瞬时干扰阻断Bid的表达,再用VES作用SGC-790细胞后,比较Bid...背景与目的:研究Bid在维生素E琥珀酸酯(vitamin E succinate,VES)诱导人胃癌SGC-7901细胞凋亡中的作用。材料与方法:在VES诱导SGC-7901细胞凋亡过程中,检测Bid蛋白的活化;用RNA瞬时干扰阻断Bid的表达,再用VES作用SGC-790细胞后,比较Bid阴性表达和Bid阳性表达细胞的凋亡率、线粒体膜电位(ΔΨm)、胞浆中细胞色素C含量和PARP活化程度。结果:VES作用细胞后Bid发生活化;Bid阴性表达细胞的凋亡率较Bid阳性表达细胞降低,线粒体膜电位升高,胞浆中细胞色素C含量减少,PARP活化减弱。结论:在VES诱导SGC-7901细胞凋亡过程中,Bid可能发挥重要作用。展开更多
文摘目的:研究维生素E琥珀酸酯(vitamin E succinate,VES)是否可通过氧化应激来诱导胃癌细胞凋亡及其可能机制。方法:分别用5、10和20μg/ml的VES处理胃癌SGC-7901细胞24h,同时设阴性对照组和甘露醇(活性氧抑制剂)预处理组。通过流式细胞技术、共聚焦技术和Western blot方法,检测了VES诱导SGC-7901细胞线粒体氧化损伤及细胞凋亡的情况,用相应的检测试剂盒检测细胞内活性氧和Ca2+含量变化情况。结果:不同浓度的VES对SGC-7901细胞均有诱导凋亡的作用。表现为随VES浓度的增加,SGC-7901细胞凋亡数量呈现增加的趋势,且SGC_7901细胞内活性氧含量及钙离子水平呈现增加的趋势,而线粒体膜电位逐渐下降。活性氧抑制剂甘露醇(1mmol/L)对VES诱导的胃癌细胞凋亡,和细胞内活性氧、钙浓度的增高及膜电位的降低均有显著抑制作用(P<0.05)。随VES浓度的增加,SGC_7901细胞内Bax蛋白的表达呈现上升的趋势,而Bcl-2蛋白的表达呈现下降趋势。甘露醇可显著降低胃癌SGC-7901细胞Bax蛋白的表达水平,同时增加Bcl-2蛋白的表达(P<0.05)。结论:VES可显著促进胃癌细胞凋亡,并且随着VES剂量的增加,VES诱导胃癌细胞凋亡的作用越强。细胞内活性氧含量增加、细胞内钙超载所导致的线粒体氧化损伤作用可能是VES诱导细胞凋亡的机制之一。
基金Supported by the National High-Tech Research and Development Program of China（No.2011AA02A209）, the Key Project of National Natural Science Foundation of China（No.20936002） and the National Natural Science Foundation of China for Young Scholars（No.20906049）.
文摘A screening of commercially available lipases for the synthesis of vitamin E succinate showed that lipase from Candida rugosa presented the highest yield. The synthesis of vitamin E succinate in organic solvents with dif- ferent lgP values ranging from -1.3 to 3.5 was investigated. Of particular interest was that dimethyl sulfoxide （DMSO） with the lowest lgP exhibited the highest yield among all the organic solvents used. It suggests that lgP is incapable of satisfactorily predicting the biocompatibility of organic solvents due to the complexity of enzymatic reaction with hydrophilic and hydrophobic substrates in organic solvent. Effects of different operating conditions, such as molar ratio of substrate, enzyme concentration, reaction temperature, mass transfer, and reaction time were also studied. Under the optimum conditions of 10 g/L enzyme, a stirring rate of 100 r/min, a substrate molar ratio of 5：1 at 55℃ for 18 h, a satisfactory yield（46.95%） was obtained. The developed method has a potential to be used for efficient enzymatic production of vitamin E succinate.
文摘背景与目的:研究Bid在维生素E琥珀酸酯(vitamin E succinate,VES)诱导人胃癌SGC-7901细胞凋亡中的作用。材料与方法:在VES诱导SGC-7901细胞凋亡过程中,检测Bid蛋白的活化;用RNA瞬时干扰阻断Bid的表达,再用VES作用SGC-790细胞后,比较Bid阴性表达和Bid阳性表达细胞的凋亡率、线粒体膜电位(ΔΨm)、胞浆中细胞色素C含量和PARP活化程度。结果:VES作用细胞后Bid发生活化;Bid阴性表达细胞的凋亡率较Bid阳性表达细胞降低,线粒体膜电位升高,胞浆中细胞色素C含量减少,PARP活化减弱。结论:在VES诱导SGC-7901细胞凋亡过程中,Bid可能发挥重要作用。
