目的采用高内涵技术筛选补骨脂潜在肝毒性成分及其可能的作用机制。方法采用CCK-8法测定补骨脂中异补骨脂二氢黄酮、补骨脂二氢黄酮甲醚、补骨脂二氢黄酮、异补骨脂查尔酮、4’-O-甲基补骨脂查尔酮、补骨脂宁、补骨脂素、异补骨脂素、...目的采用高内涵技术筛选补骨脂潜在肝毒性成分及其可能的作用机制。方法采用CCK-8法测定补骨脂中异补骨脂二氢黄酮、补骨脂二氢黄酮甲醚、补骨脂二氢黄酮、异补骨脂查尔酮、4’-O-甲基补骨脂查尔酮、补骨脂宁、补骨脂素、异补骨脂素、补骨脂定、补骨脂酚10种成分的IC_(50)值。在相同浓度药物处理HepG 2细胞24 h后,进行高内涵检测,通过阳性细胞的平均荧光强度评价各组细胞活性氧、还原型谷胱甘肽、线粒体膜电位及线粒体超氧化物水平4个指标的变化情况,初步筛选补骨脂中主要肝毒性成分。结果CCK-8细胞活力实验结果显示,异补骨脂二氢黄酮、补骨脂二氢黄酮甲醚、补骨脂二氢黄酮、异补骨脂查尔酮、4’-O-甲基补骨脂查尔酮、补骨脂宁、异补骨脂素、补骨脂定、补骨脂酚对Hep G 2细胞的IC_(50)值分别为52.69、42.72、83.63、42.29、57.43、110.80、1420.00、23.58和25.34μmol·L^(-1)。高内涵结果显示,在20μmol·L^(-1)浓度下,补骨脂二氢黄酮甲醚、补骨脂二氢黄酮、异补骨脂查尔酮、补骨脂定和补骨脂酚可显著提高细胞内活性氧水平;异补骨脂查尔酮、4’-O-甲基补骨脂查尔酮、补骨脂宁、异补骨脂素、补骨脂定和补骨脂酚均可导致细胞中还原型谷胱甘肽水平保护性升高;异补骨脂查尔酮、补骨脂定和补骨脂酚均显著降低线粒体膜电位,造成线粒体超氧化物累积。结论异补骨脂查尔酮、补骨脂定和补骨脂酚是补骨脂中造成线粒体功能损伤的主要成分,具有潜在的肝脏毒性,其具体作用机制有待进一步研究。展开更多
Objective Hepatocellular carcinoma(HCC)is the third leading cause of cancer-associated death worldwide.As a first-line drug for advanced HCC treatment,lenvatinib faces a significant hurdle due to the development of bo...Objective Hepatocellular carcinoma(HCC)is the third leading cause of cancer-associated death worldwide.As a first-line drug for advanced HCC treatment,lenvatinib faces a significant hurdle due to the development of both intrinsic and acquired resistance among patients,and the underlying mechanism remains largely unknown.The present study aims to identify the pivotal gene responsible for lenvatinib resistance in HCC,explore the potential molecular mechanism,and propose combinatorial therapeutic targets for HCC management.Methods Cell viability and colony formation assays were conducted to evaluate the sensitivity of cells to lenvatinib and dicoumarol.RNA-Seq was used to determine the differences in transcriptome between parental cells and lenvatinib-resistant(LR)cells.The upregulated genes were analyzed by GO and KEGG analyses.Then,qPCR and Western blotting were employed to determine the relative gene expression levels.Afterwards,the intracellular reactive oxygen species(ROS)and apoptosis were detected by flow cytometry.Results PLC-LR and Hep3B-LR were established.There was a total of 116 significantly upregulated genes common to both LR cell lines.The GO and KEGG analyses indicated that these genes were involved in oxidoreductase and dehydrogenase activities,and reactive oxygen species pathways.Notably,NAD(P)H:quinone oxidoreductase 1(NQO1)was highly expressed in LR cells,and was involved in the lenvatinib resistance.The high expression of NQO1 decreased the production of ROS induced by lenvatinib,and subsequently suppressed the apoptosis.The combination of lenvatinib and NQO1 inhibitor,dicoumarol,reversed the resistance of LR cells.Conclusion The high NQO1 expression in HCC cells impedes the lenvatinib-induced apoptosis by regulating the ROS levels,thereby promoting lenvatinib resistance in HCC cells.展开更多
Enhancing the stability of supported noble metal catalysts emerges is a major challenge in both science and industry.Herein,a heterogeneous Pd catalyst(Pd/NCF)was prepared by supporting Pd ultrafine metal nanoparticle...Enhancing the stability of supported noble metal catalysts emerges is a major challenge in both science and industry.Herein,a heterogeneous Pd catalyst(Pd/NCF)was prepared by supporting Pd ultrafine metal nanoparticles(NPs)on nitrogen-doped carbon;synthesized by using F127 as a stabilizer,as well as chitosan as a carbon and nitrogen source.The Pd/NCF catalyst was efficient and recyclable for oxidative carbonylation of phenol to diphenyl carbonate,exhibiting higher stability than Pd/NC prepared without F127 addition.The hydrogen bond between chitosan(CTS)and F127 was enhanced by F127,which anchored the N in the free amino group,increasing the N content of the carbon material and ensuring that the support could provide sufficient N sites for the deposition of Pd NPs.This process helped to improve metal dispersion.The increased metal-support interaction,which limits the leaching and coarsening of Pd NPs,improves the stability of the Pd/NCF catalyst.Furthermore,density functional theory calculations indicated that pyridine N stabilized the Pd^(2+)species,significantly inhibiting the loss of Pd^(2+)in Pd/NCF during the reaction process.This work provides a promising avenue towards enhancing the stability of nitrogen-doped carbon-supported metal catalysts.展开更多
Understanding the influence of purities on the electrochemical performance of pure aluminum(Al)in alkaline media for Al–air batteries is significant.Herein,we comprehensively investigate secondary phase precipitate(S...Understanding the influence of purities on the electrochemical performance of pure aluminum(Al)in alkaline media for Al–air batteries is significant.Herein,we comprehensively investigate secondary phase precipitate(SPP)-induced localized corrosion of pure Al in NaOH solution mainly based on quasi-in-situ and cross-section observations under scanning electron microscopy coupled with finite element simulation.The experimental results indicate that Al–Fe SPPs appear as clusters and are coherent with the Al substrate.In alkaline media,Al–Fe SPPs exhibit more positive potentials than the substrate,thus aggravating localized galvanic corrosion as cathodic phases.Moreover,finite element simulation indicates that the irregular geometry coupled with potential difference produces the non-uniform current density distribution inside the SPP cluster,and the current density on the Al substrate gradually decreases with distance.展开更多
文摘目的采用高内涵技术筛选补骨脂潜在肝毒性成分及其可能的作用机制。方法采用CCK-8法测定补骨脂中异补骨脂二氢黄酮、补骨脂二氢黄酮甲醚、补骨脂二氢黄酮、异补骨脂查尔酮、4’-O-甲基补骨脂查尔酮、补骨脂宁、补骨脂素、异补骨脂素、补骨脂定、补骨脂酚10种成分的IC_(50)值。在相同浓度药物处理HepG 2细胞24 h后,进行高内涵检测,通过阳性细胞的平均荧光强度评价各组细胞活性氧、还原型谷胱甘肽、线粒体膜电位及线粒体超氧化物水平4个指标的变化情况,初步筛选补骨脂中主要肝毒性成分。结果CCK-8细胞活力实验结果显示,异补骨脂二氢黄酮、补骨脂二氢黄酮甲醚、补骨脂二氢黄酮、异补骨脂查尔酮、4’-O-甲基补骨脂查尔酮、补骨脂宁、异补骨脂素、补骨脂定、补骨脂酚对Hep G 2细胞的IC_(50)值分别为52.69、42.72、83.63、42.29、57.43、110.80、1420.00、23.58和25.34μmol·L^(-1)。高内涵结果显示,在20μmol·L^(-1)浓度下,补骨脂二氢黄酮甲醚、补骨脂二氢黄酮、异补骨脂查尔酮、补骨脂定和补骨脂酚可显著提高细胞内活性氧水平;异补骨脂查尔酮、4’-O-甲基补骨脂查尔酮、补骨脂宁、异补骨脂素、补骨脂定和补骨脂酚均可导致细胞中还原型谷胱甘肽水平保护性升高;异补骨脂查尔酮、补骨脂定和补骨脂酚均显著降低线粒体膜电位,造成线粒体超氧化物累积。结论异补骨脂查尔酮、补骨脂定和补骨脂酚是补骨脂中造成线粒体功能损伤的主要成分,具有潜在的肝脏毒性,其具体作用机制有待进一步研究。
基金supported by the Global Select Project(No.DJK-LX-2022001)of the Institute of Health and Medicine,Hefei Comprehensive National Science Center.
文摘Objective Hepatocellular carcinoma(HCC)is the third leading cause of cancer-associated death worldwide.As a first-line drug for advanced HCC treatment,lenvatinib faces a significant hurdle due to the development of both intrinsic and acquired resistance among patients,and the underlying mechanism remains largely unknown.The present study aims to identify the pivotal gene responsible for lenvatinib resistance in HCC,explore the potential molecular mechanism,and propose combinatorial therapeutic targets for HCC management.Methods Cell viability and colony formation assays were conducted to evaluate the sensitivity of cells to lenvatinib and dicoumarol.RNA-Seq was used to determine the differences in transcriptome between parental cells and lenvatinib-resistant(LR)cells.The upregulated genes were analyzed by GO and KEGG analyses.Then,qPCR and Western blotting were employed to determine the relative gene expression levels.Afterwards,the intracellular reactive oxygen species(ROS)and apoptosis were detected by flow cytometry.Results PLC-LR and Hep3B-LR were established.There was a total of 116 significantly upregulated genes common to both LR cell lines.The GO and KEGG analyses indicated that these genes were involved in oxidoreductase and dehydrogenase activities,and reactive oxygen species pathways.Notably,NAD(P)H:quinone oxidoreductase 1(NQO1)was highly expressed in LR cells,and was involved in the lenvatinib resistance.The high expression of NQO1 decreased the production of ROS induced by lenvatinib,and subsequently suppressed the apoptosis.The combination of lenvatinib and NQO1 inhibitor,dicoumarol,reversed the resistance of LR cells.Conclusion The high NQO1 expression in HCC cells impedes the lenvatinib-induced apoptosis by regulating the ROS levels,thereby promoting lenvatinib resistance in HCC cells.
基金support by the National Natural Science Foundation of China(U21A20306,U20A20152)Natural Science Foundation of Hebei Province(B2022202077).
文摘Enhancing the stability of supported noble metal catalysts emerges is a major challenge in both science and industry.Herein,a heterogeneous Pd catalyst(Pd/NCF)was prepared by supporting Pd ultrafine metal nanoparticles(NPs)on nitrogen-doped carbon;synthesized by using F127 as a stabilizer,as well as chitosan as a carbon and nitrogen source.The Pd/NCF catalyst was efficient and recyclable for oxidative carbonylation of phenol to diphenyl carbonate,exhibiting higher stability than Pd/NC prepared without F127 addition.The hydrogen bond between chitosan(CTS)and F127 was enhanced by F127,which anchored the N in the free amino group,increasing the N content of the carbon material and ensuring that the support could provide sufficient N sites for the deposition of Pd NPs.This process helped to improve metal dispersion.The increased metal-support interaction,which limits the leaching and coarsening of Pd NPs,improves the stability of the Pd/NCF catalyst.Furthermore,density functional theory calculations indicated that pyridine N stabilized the Pd^(2+)species,significantly inhibiting the loss of Pd^(2+)in Pd/NCF during the reaction process.This work provides a promising avenue towards enhancing the stability of nitrogen-doped carbon-supported metal catalysts.
基金financially supported by the National Natural Science Foundation of China(No.51901018)the Young Elite Scientists Sponsorship Program by the China Association for Science and Technology(YESS,No.2019 QNRC001)+3 种基金the Fundamental Research Funds for the Central Universities,China(No.FRF-AT-20-07,06500119)the Natural Science Foundation of Beijing Municipality,China(No.2212037)the National Science and Technology Resources Investigation Program of China(No.2019FY 101400)the Southwest Institute of Technology and Engineering Cooperation Fund,China(No.HDHDW5902020107)。
文摘Understanding the influence of purities on the electrochemical performance of pure aluminum(Al)in alkaline media for Al–air batteries is significant.Herein,we comprehensively investigate secondary phase precipitate(SPP)-induced localized corrosion of pure Al in NaOH solution mainly based on quasi-in-situ and cross-section observations under scanning electron microscopy coupled with finite element simulation.The experimental results indicate that Al–Fe SPPs appear as clusters and are coherent with the Al substrate.In alkaline media,Al–Fe SPPs exhibit more positive potentials than the substrate,thus aggravating localized galvanic corrosion as cathodic phases.Moreover,finite element simulation indicates that the irregular geometry coupled with potential difference produces the non-uniform current density distribution inside the SPP cluster,and the current density on the Al substrate gradually decreases with distance.
