Development of new methods for risk assessment on multi-chemical exposure to human fetus

1.脐带环境化学物质暴露水平及基因表达分析：以双生子S为研究对象，探讨脐带环境化学物质暴露水平与基因表达的关系。研究发现，母体是影响基因表达的环境因素之一。当人脐静脉平滑肌细胞(HUVSMC)暴露于多氯联苯(PCB77和PCB126，非共面PCBS：PCB153)和3-甲基胆蒽(3mc，二恶英类化合物之一)时，DNA芯片和实时定量PCR下调eNOS、NPPB和IL-6的表达。由于这些基因涉及血管构建，因此可能会影响胎儿的发育。由于认为化学物质对DNA的表观遗传学有影响，我们采用原位杂交和免疫组织化学的方法对Dmnts、DNA甲基化酶进行了研究。为了了解日本人接触多氯联苯的现状，我们分析了包括婴儿在内的406人的血液中多氯联苯水平。有母乳喂养的婴儿的PCB值高于无母乳喂养的婴儿。成人的多氯联苯水平随着年龄的增长而增加。以多氯联苯为指示剂。为了研究宫内化学物质暴露与过敏的关系，我们利用脐带库系统构建了随访系统。

1. Analysis of gene expression and assessment of exposure level of environmental chemicals of umbilical cord: To investigate association of gene expression and exposure level of umbilical cord, five pair s of twin were used. It is found that maternal body, one of the environmental factors, affected gene expression. When human umbilical vein smooth muscle cells (HUVSMC) were exposed to polychlorinated biphenyls (coplanar PCBs: PCB77 and PCB126, non-coplanar PCBs: PCB153) and 3-methylcholanthrene (3MC, one of the dioxin-like compound), eNOS, NPPB, and IL-6 were down regulated by DNA microarray and real-time PCR. Because these genes involved blood vessel construction, it may be affected to fetal development.2. Because it is thought that chemicals affect to epigenetics of DNA, we investigated on Dmnts, DNA methylation enzymes by in situ hybridization and immunohistochemistry.3. To know current situation of PCB exposure of Japanese, we analyzed blood PCB levels of 406 people including infants. PCB levels of infant with breast milk were higher than without breast milk. Adult PCB levels increased as age. PCB was indicator as chlorinated chemicals.4. To investigate association of chemical exposure in utero and allergy, we constructed follow up system using bank system of umbilical cord.