镉诱导文蛤鳃细胞凋亡和抗氧化生物标志物的响应  

Apoptosis of Meretrix meretrix Gill Cell and Response of Antioxidative Bio-markers Induced by Cadmium

作　　者：王进华 柏彬彬 邓婉菲 邹婷 应雪萍[1] Wang Jinhua;Bai Binbin;Deng Wanfei;Zou Ting;Ying Xueping(College of Life and Environmental Sciences,Wenzhou University,Wenzhou 325035,China)

机构地区：[1]温州大学生命与环境科学学院,温州325035

出　　处：《生态毒理学报》2022年第2期413-423,共11页Asian Journal of Ecotoxicology

基　　金：国家自然科学基金资助项目(32071514);浙江省自然科学基金资助项目(LY18C030005)。

摘　　要：镉(Cd)是水生环境中主要的污染物之一,易在水生动物体内富集并产生毒害作用,而鳃是重金属积累的主要器官。本研究用不同浓度Cd^(2+)溶液(0、1.5、3、6和12 mg·L^(-1))对文蛤进行染毒,用形态学、生化及分子生物学方法检测Cd^(2+)诱导下文蛤鳃细胞凋亡程度以及抗氧化生物标志物的响应特点。结果显示,随着Cd^(2+)浓度的上升,细胞凋亡程度不断加深,同时鳃中活性氧(ROS)含量、DNA-蛋白质交联率(DPC)和蛋白质羰基(PCO)含量均显著上升;但超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GPx)活性及MT mRNA表达量随Cd^(2+)浓度的升高均呈先升后降的趋势;超微量Na^(+)-K^(+)ATP酶、Ca^(2+)-Mg^(2+)ATP酶和总ATP酶活性呈抑制状态;且最高浓度组的总抗氧化能力(T-AOC)水平也受到抑制。说明Cd^(2+)能诱导文蛤产生ROS,破坏ATP酶活性,造成氧化损伤和功能紊乱,机体的抗氧化应激系统对外源Cd^(2+)有一定的抗氧化作用,但随着Cd^(2+)浓度的上升其抗氧化应激能力逐渐减弱。Cadmium(Cd)is one of the main pollutants in aquatic environment that can accumulate in aquatic animal bodies and cause oxidative damage.Gill is one of the main target organs of Cd toxicity.In this study,we investigated the effect of Cd on the gill of Meretrix meretrix and the responses of the antioxidative biomarkers fol-lowing exposure to different Cd^(2+)concentrations(0,1.5,3,6 and 12 mg·L^(-1)).Typical morphological characteristics,physiological changes of oxidative damage,as well as the apoptosis of the gill were observed by using various methods,including AO/EB double fluorescence staining,DNA fragmentation and biochemical index analysis.Multiple antioxidative biomarkers,including superoxide dismutase(SOD),catalase(CAT),glutathione peroxidase(GPx),Na^(+)-K^(+)ATPase,Ca^(2+)-Mg^(2+)ATPase,T-ATPase and MT mRNA,were measured in gill cell of clam.The re-sults showed that Cd^(2+)induced apoptosis is in a concentration-dependent manner.The activities of SOD,CAT and GPx,and MT mRNA expression initially increased and subsequently decreased when Cd^(2+)concentrations were in-creased.This was accompanied by increasing the levels of reactive oxygen species(ROS),DNA-protein crosslink-ing rate(DPC)and protein carbonyl(PCO)in gills.However,the activities of Na^(+)-K^(+)ATPase,Ca^(2+)-Mg^(2+)ATPase and T-ATPase were inhibited when Cd^(2+)concentration was increased.The level of total antioxidant capacity(T-AOC)in the higher Cd^(2+)concentration group were also inhibited.Taken together,our results indicated that Cd^(2+)could induce oxidative damage in clam gill cells in a concentration-dependent manner.The antioxidative stress sys-tem of the clam could exert antioxidant effect on Cd^(2+),but the ability to resist oxidative stress gradually weakened with the increase of Cd^(2+)concentration.

关 键 词：镉 文蛤 鳃 细胞凋亡 抗氧化生物标志物 

分 类 号：X171.5[环境科学与工程—环境科学]