摘要
目的探讨胎盘对低剂量镉(cadmium,Cd)暴露的屏障作用及相关作用蛋白。方法模拟职业人群的暴露水平,建立连续低剂量Cd(1 mg/kg·bw·d)暴露的大鼠生殖毒性试验模型(44 d),通过石墨炉原子吸收光谱法和DIGE(differential in-gel electrophoresis)荧光标记蛋白质组学方法观察低剂量Cd通透胎盘的比例及可能的作用蛋白。结果与容易透过胎盘的重金属铅(lead,Pb)相比,Cd通过胎盘的比例明显降低。其中染毒44 d母鼠血Cd浓度(16.70±4.77)μg/L,胎鼠脐血Cd浓度(1.40±1.17)μg/L,脐血Cd/母血Cd约为8.38%,与对照组相比差异无统计学意义(P>0.05);母鼠血Pb浓度为(284.95±149.49)μg/L,胎鼠脐血Pb浓度为(165.73±52.17)μg/L,脐血Pb/母血Pb约为58.20%(P<0.05)。蛋白质组学分析发现了13个差异表达的蛋白,根据蛋白的表达模式及生物学功能,筛选出3个差异蛋白进一步分析,分别为内质网应激蛋白Grp94(heat shock protein 90 k Da beta member 1,Grp94)、内质网应激蛋白Grp78(heat shock 70 k Da protein 5,Grp78)和抑制素(prohibitin,PHB)。结论胎盘对低剂量Cd(1 mg/kg·bw·d)暴露有明显的屏障作用,Grp94、Grp78和PHB蛋白可能参与该作用的发挥,具体的转运机制有待深入探讨。
Objective To detect the effects of placental barrier and relevant proteins in rats exposed to low level cadmium.Methods The animal reproductive test on low level cadmium（ 1 mg / kg·bw·d） was carried out,mimicking the conditions of actual occupational exposure of cadmium. The ratio of penetration to the placenta of cadmium was measured with atomic absorption spectrometer（ AAS） and the proteins were analyzed using proteomics analysis. Results The penetration capacities of the placenta are totally different between the cadmium and lead. The ratio of umbilical cord cadmium [（ 1. 40 ± 1. 17） μg / L] to maternal blood cadmium [（ 16. 70 ± 4. 77）μg /L]was only 8. 38%. No significant difference was found compared with the control（P〈0. 05）. But the ratio of the umbilical cord lead[（ 165. 73 ±52. 17） μg/L]to maternal blood lead [（ 284. 95 ± 149. 49） μg/L]was up to 58. 20%（P〈0. 05）. A total of 13 protein spots differentially expressed were detected. Based on the expression pattern and the biological functions of protein spots in each group,three proteins were selected for further analysis,including Grp94,Grp78 and PHB. Conclusion The above results indicate that placenta is a significant barrier for low level exposure of cadmium,the barrier effects are probably associated with the oxidative stress.
出处
《毒理学杂志》
CAS
CSCD
北大核心
2015年第4期247-252,共6页
Journal of Toxicology
基金
国家自然科学基金(81302465)
广东省职业病防治重点实验室项目(2012A061400007)
十二五国家科技支撑计划项目(2014BAI12B01)
关键词
镉
铅
胎盘屏障
蛋白质组学
Cadmium
Lead
Proteomics
Placental barrier
