目的:研究细胞外半胱氨酸/胱氨酸氧化还原电位(EhCys/Cy SS)对非酒精性脂肪肝(NAFLD)肝细胞线粒体功能的影响。方法:用EhCys/Cy SS分别为0 m V(氧化)、-80 m V(正常)和-150 m V(还原)的氧化还原培养基培养肝细胞株LO2并采用油酸诱导细...目的:研究细胞外半胱氨酸/胱氨酸氧化还原电位(EhCys/Cy SS)对非酒精性脂肪肝(NAFLD)肝细胞线粒体功能的影响。方法:用EhCys/Cy SS分别为0 m V(氧化)、-80 m V(正常)和-150 m V(还原)的氧化还原培养基培养肝细胞株LO2并采用油酸诱导细胞建立NAFLD模型。荧光探针DCFH-DA和Mito SOX分别检测细胞整体水平和线粒体活性氧簇(ROS)生成,使用apocynin(NADPH氧化酶抑制剂)和Mito Q10(靶向线粒体抗氧化剂)、rotenone(线粒体呼吸链复合体I抑制剂)和antimycin A(线粒体呼吸链复合体Ⅲ抑制剂)作用细胞检测线粒体复合体活性从而探究ROS的来源,JC-1检测细胞线粒体膜电位。结果:油酸诱导的NAFLD细胞模型使肝细胞内ROS增多,线粒体膜电位下降;氧化的EhCys/Cy SS加剧了NAFLD肝细胞ROS的生成以及线粒体膜电位的下降,而还原的EhCys/Cy SS能清除ROS并逆转线粒体膜电位的下降。线粒体ROS清除剂Mito Q10能显著地减少氧化的EhCys/Cy SS所增加的ROS,而apocynin效果不明显。Rotenone作用于细胞后,ROS的增长率与细胞外EhCys/Cy SS有关,氧化状态下ROS增长率最小且复合体I活性减弱,即氧化的EhCys/Cy SS能通过抑制线粒体复合体I增加ROS的生成。结论:氧化的EhCys/Cy SS能通过抑制线粒体复合体I,从而加剧NAFLD肝细胞ROS的生成,并使线粒体膜电位进一步下降,而还原的EhCys/Cy SS能减少高脂所致ROS生成并减轻线粒体损伤。展开更多
Nitric oxide(NO),which generally originates from vehicle exhaust and industrial flue gases,is one of the most serious air pollutants.In this case,the electrochemical NO reduction reaction(NORR)not only removes the atm...Nitric oxide(NO),which generally originates from vehicle exhaust and industrial flue gases,is one of the most serious air pollutants.In this case,the electrochemical NO reduction reaction(NORR)not only removes the atmospheric pollutant NO but also produces valuable ammonia(NH_(3)).Hence,through the synthesis and modification of Fe_(3)C nanocrystal cata-lysts,the as-obtained optimal sample of Fe_(3)C/C-900 was adopted as the NORR catalyst at ambient conditions.As a result,the Fe_(3)C/C-900 catalyst showed an NH_(3)Faraday efficiency of 76.5%and an NH_(3)yield rate of 177.5μmol·h^(-1)·cm^(-2)at the working potentials of-0.8 and-1.2 V versus reversible hydrogen electrode(vs.RHE),respectively.And it delivered a stable NORR activity during the electrolysis.Moreover,we attribute the high NORR properties of Fe_(3)C/C-900 to two aspects:one is the enhanced intrinsic activity of Fe_(3)C nanocrystals,including the lowering of the energy barrier of rate-limiting step(*NOH→*N)and the inhibition of hydrogen evolution;on the other hand,the favorable dispersion of active components,the effective adsorption of gaseous NO,and the release of liquid NH_(3)products facilitated by the porous carbon substrate.展开更多
基金supported by the Guangxi Natural Science Fund for Distinguished Young Scholars(2024GXNSFFA010008)Shenzhen Science and Technology Program(JCYJ20230807112503008).
文摘Nitric oxide(NO),which generally originates from vehicle exhaust and industrial flue gases,is one of the most serious air pollutants.In this case,the electrochemical NO reduction reaction(NORR)not only removes the atmospheric pollutant NO but also produces valuable ammonia(NH_(3)).Hence,through the synthesis and modification of Fe_(3)C nanocrystal cata-lysts,the as-obtained optimal sample of Fe_(3)C/C-900 was adopted as the NORR catalyst at ambient conditions.As a result,the Fe_(3)C/C-900 catalyst showed an NH_(3)Faraday efficiency of 76.5%and an NH_(3)yield rate of 177.5μmol·h^(-1)·cm^(-2)at the working potentials of-0.8 and-1.2 V versus reversible hydrogen electrode(vs.RHE),respectively.And it delivered a stable NORR activity during the electrolysis.Moreover,we attribute the high NORR properties of Fe_(3)C/C-900 to two aspects:one is the enhanced intrinsic activity of Fe_(3)C nanocrystals,including the lowering of the energy barrier of rate-limiting step(*NOH→*N)and the inhibition of hydrogen evolution;on the other hand,the favorable dispersion of active components,the effective adsorption of gaseous NO,and the release of liquid NH_(3)products facilitated by the porous carbon substrate.
