Differential expression of serum proteins in chromic arsenic exposed population / 中国地方病学杂志

ABSTRACT

Objectives To screen the differentially expressed proteins in serum of population chronically exposed to arsenic in drinking water,thus to provide candidate protein biomarkers for arsenic exposure and arsenicosis.Methods Subjects were selected from the drinking water type of endemic arsenicosis areas in Shanxi province,China.Demographic characteristics,history of arsenic exposure,cigarette smoking,alcohol drinking,health and other information were collected using questionnaire.The subjects were divided into low-arsenic group (with arsenic in drinking water ＜ 10 μg/L),medium-arsenic group( 10 - 50 μg/L),high-arsenic group( ＞ 50 μg/L),and arsenicosis group(the drinking water with arsenic ＞ 50 μg/L was replaced by low arsenic water ＜ 10 μg/L).The number of cases in each group was 30.The arsenicosis patients were diagnosed according to “Standard of Diagnosis for Endemic Arsenism” (WS/T 211-2001 ).With the principle of informed consent,blood samples were collected.Differentially expressed serum proteins of different arsenic exposure groups and arsenicosis group were screened by two-dimensional differential gel electrophoresis(2-D DIGE),and further identified by mass spectrometry (MS).Results An average of (1299 ± 167) protein spots were identified in 6 gel images and 688 protein spots were discovered repeatedly in at least 5 gels.There were 33 protein spots differentially expressed among low-,medium- and high-arsenic groups P ＜ 0.01).Fifty four protein spots were significantly different among low-,medium-,high-arsenic exposure groups and arsenicosis group(P ＜ 0.01 ).Twenty five protein spots were selected for MS analysis,and13 protein spots were identified.Compared with low-arsenic group,the expressions of apolipoprotein A-Ⅳ,retinol binding protein,and estrogen receptor hypothalamic isoform in medium- and higharsenic exposure groups were down regulated,and the expressions of component 4A and 4B were up regulated.Compared with low-,medium- and high-arsenic groups,the expressions of beta-2-glycoprotein Ⅰ,Keratin 1,hemopexin,complement C1r subcomponent,and ficolin-3 in arsenicosis group were down regulated,and the expressions of pigment epithelial-differentiating factor,alpha-1-microglobulin and carboxypeptidase N catalytic chain were up regulated.Conclusions Chronic arsenic exposure can significantly change population's serum protein expression.Differentially expressed proteins in arsenicosis patients will not decline with the decline of arsenic in a short term.Whether or not the differentially expressed proteins identified in this study can be used as biomarkers for arsenic exposure and arsenicosis needs to be further verified.