低剂量砷染毒SD大鼠肝脏差异蛋白的研究

Low-dosage arsenic-induced expression of differential liver proteins in rats

目的观察低剂量急性砷染毒SD大鼠肝脏差异蛋白,为筛选有意义的低剂量砷中毒早期肝脏改变的特异性生物标志物提供依据。方法健康雄性SD大鼠48只,体质量180～220g,按体质量随机分为4组,每组12只,分别饮用含亚砷酸钠0、0.05、0.15、0.45mg/L的水。染毒4周后断头处死。采用双向凝胶电泳技术,对低剂量砷染毒后的大鼠肝脏蛋白表达谱进行分析。结果与对照组相比,0.05mg/L剂量组不表达的蛋白质点数有31个,表达下调的蛋白质点数有11个,表达上调的蛋白质点数1个;0.15mg/L剂量组不表达的蛋白质点数有23个,表达下调的蛋白质点数有15个,没有出现表达上调的蛋白质点数;0.45mg/L剂量组没有出现不表达的蛋白质点数,表达下调的蛋白质点数有8个,表达上调的蛋白质点数1个。结论染砷组肝脏差异蛋白主要表现为表达下调或不表达,染毒0.05mg/L剂量和0.15mg/L剂量不表达和表达下调的蛋白质点较多,其中重复不表达和重复表达下调的蛋白质点居多数,这些重复的蛋白质点可能和低剂量砷中毒肝脏早期损伤有密切的联系。

Objective To study differential liver protein expression in SD rats exposed to low-dosage arsenic for further provision of rationales to screen the biomarkers specific to early-stage liver injury.Methods Forty-eight healthy SD rats weighed 180-220 grams were randomly assigned to four groups（12 per group） to expose to water containing 0 mg/L,0.05 mg/L,0.15 mg/L and 0.45 mg/L sodium arsenite,respectively,on the basis of body weight.This was followed by sentences of all rats at week 4.Two-dimensional gel electrophoresis（2-DE） was employed to analyze the expression spectrum of liver proteins in rats exposed to low-dosage arsenic.Results The 0.05 mg/L group yielded 31 non-expression spots,11 down-regulated spots and 1 up-regulated spot,as compared with control group.In addition to absence of up-regulated spots,there were 23 and 15 spots showing non-expression and down-regulation,respectively,in the 0.15 mg/L group.Furthermore,8 down-regulated spots,an up-regulated spot and absence of non-expression spots were explored in the 0.45 mg/L group.Conclusion Upon obtaining high-resolution and reproducible 2-DE spectrum in rats exposed to low-dosage arsenic,liver differential proteins were mostly down-regulated or even silenced in all arsenic exposure groups.These spots,in particular,consistently down-regulated or silenced in both 0.05 mg/L and 0.15 mg/L groups,suggested potential correlation with early-phase low-dosage arsenic-induced liver injury.