铅暴露对斑马鱼胚胎心脏和脊柱发育的影响  

Effects of lead exposure on development of heart and spine in zebrafish embryos

作　　者：李萍萍 闫晓涛 张金花 刘晓艺 王斌 张红[1,2] 司婧 LI Pingping;YAN Xiaotao;ZHANG Jinhua;LIU Xiaoyi;WANG Bin;ZHANG Hong;SI Jing(Medical Physics Department,Institute of Modern Physics/Key Laboratory of Heavy Ion Radiation Biology and Medicine,Chinese Academy of Sciences,Lanzhou,Gansu 730000,China;College of Life Sciences,University of Chinese Academy of Sciences,Beijing 101408,China;Technology Innovation Office,Lanzhou City Water Supply(Group)Co.Ltd,Lanzhou,Gansu 730060,China;College of Life Sciences,Lanzhou University,Lanzhou,Gansu 730000,China)

机构地区：[1]中国科学院,近代物理研究所医学物理室/重离子束辐射生物医学重点实验室,甘肃兰州730000 [2]中国科学院大学生命科学学院,北京101408 [3]兰州城市供水(集团)有限公司科技创新办公室,甘肃兰州730060 [4]兰州大学生命科学学院,甘肃兰州730000

出　　处：《环境与职业医学》2023年第2期196-201,215,共7页Journal of Environmental and Occupational Medicine

基　　金：兰州市人才创新创业项目(2019-RC-76);甘肃省科技计划项目(20JR5RA551)。

摘　　要：[背景]铅分布广泛。铅暴露会干扰斑马鱼生命早期发育,但铅暴露影响斑马鱼骨骼发育和心脏发育的机制尚不清楚。[目的]探究醋酸铅暴露诱发的骨发育和心脏发育毒性的分子机制。[方法]将受精后3 h(3 hpf)斑马鱼胚胎暴露于不同浓度的醋酸铅(0、6、12、24和48μmol·L^(-1)),直至受精后5天(5 dpf)。统计5dpf的畸形表型,通过荧光定量PCR方法检测脊柱发育相关基因(bmp2b、bmp4、bmp9、runx2a、runx2b)和心脏发育相关基因(nkx2.5、myh6、myh7)的mRNA表达情况,分析发育相关调控通路Wnt/β-catenin通路(wnt5a、wnt8a、wnt10a、β-catenin)、TGF-β通路(tgf-β1、tgf-β2)相关基因和Eph-Ephrin信号中关键分子eph的mRNA表达情况。[结果]5dpf时与对照组相比,醋酸铅处理组斑马鱼出现包括脊柱弯曲和心包囊水肿的畸形表型。24、48μmol·L^(-1)醋酸铅组脊柱弯曲畸形率分别达到26.47%和71.52%,高于对照组(P<0.01)。qPCR结果发现,与对照组相比,48μmol·L^(-1)暴露组中,脊柱发育相关基因bmp2b、bmp4、bmp9、runx2a、runx2b的mRNA表达分别下调82.8%、58.0%、88.7%、85.5%、69.2%(P<0.05或P<0.01),心脏发育相关基因myh6、myh7、nkx2.5的mRNA表达分别下调63.7%、58.9%、55.2%(P<0.01),Wnt/β-catenin通路中wnt8a、β-catenin的mRNA表达分别下调了71.5%、47.3%(P<0.05或P<0.01),TGF-β通路中tgf-β1的mRNA表达下调了67.5%(P<0.01),eph的mRNA表达下调了86.9%(P<0.01)。[结论]醋酸铅通过下调脊柱发育和心脏发育相关基因的mRNA表达,以及抑制发育相关Wnt/β-catenin、TGF-β通路和Eph-Ephrin信号,引起脊柱弯曲和心包囊水肿等畸形表型,从而对斑马鱼心脏和骨骼产生发育毒性作用。[Background] Lead is widely distributed. Lead exposure interferes with early life development in zebrafish, but the mechanisms by which lead exposure affects skeletal development and cardiac development are not clear as yet.[Objective] To investigate the molecular mechanisms of bone development and cardiac development toxicity induced by lead acetate exposure.[Methods] Zebrafish embryos were exposed to different concentrations of lead acetate(0, 6, 12,24, and 48 μmol·L^(-1)) for 3 h post-fertilization(3 hpf) until 5 d post-fertilization(5 dpf). The malformation phenotypes of 5 dpf were counted, and the mRNA expressions of spinal development-related genes(bmp2b, bmp4, bmp9, runx2a, runx2b) and heart development-related genes(nkx2.5, myh6, myh7) were detected by quantitative PCR(qPCR). Expressions of genes of development-related regulatory pathways including Wnt/β-catenin pathway(wnt5a, wnt8a, wnt10a, β-catenin) and TGF-β pathway(tgf-β1, tgf-β2) as well as key molecule eph of Eph-Ephrin signaling were analyzed.[Results] At 5 dpf, the zebrafish in the lead acetate treated groups showed deformed phenotypes including spinal curvature and pericardial sac edema compared to the control group. In the lead acetate groups at 24 and 48 μmol·L^(-1), the spinal curvature deformity rates reached26.47% and 71.52%(P < 0.01) respectively. The q PCR results revealed that the expression levels of spinal development-related genes bmp2b, bmp4, bmp9, runx2a, and runx2b were downregulated in the 48 μmol·L^(-1)exposure group compared to the control group by 82.8%, 58.0%, 88.7%, 85.5%, and 69.2%, respectively(P < 0.05 or P < 0.01);the expression levels of heart development-related genes myh6, myh7, and nkx2.5 were down-regulated by 63.7%, 58.9%, and 55.2%, respectively(P < 0.01);the expression levels of wnt8a and β-catenin in the Wnt/β-catenin pathway were down-regulated by 71.5% and 47.3%(P < 0.05 or P < 0.01), respectively;the expression level of tgf-β1 in the TGF-β pathway was down-regulated by 67.5%(P < 0.01);the expres

关 键 词：斑马鱼 醋酸铅 脊柱弯曲 心包囊水肿 Wnt/β-catenin通路 TGF-β通路 Eph-Ephrin信号 

分 类 号：R114[医药卫生—卫生毒理学]