基于质谱技术的双酚A与DNA加合物检测方法的研究及其应用

Bisphenol A (BPA) is an important industrial chemical used in the manufacture of polycarbonate plastics and other products. It has been reported that the BPA exposure may be associated with an increased risk cancer. However, the mechanism of increasing risk of cancer induced by the BPA exposure has not been reported clearly. DNA adducts is the most important chemical and the most important and commonly mode of DNA damage. Detection of DNA adduct can provide the exact interior dosage and help to illuminate the toxicology mechanism. This proposal aims to establish a rapid, high-throughput, and sensitive method base on mass spectrometry (MS) for characterization and determination of BPA-DNA adducts. High resolution and sensitivity MS will be applied for the characterization and quantitative determination of DNA adducts. The BPA-DNA adducts in four type cell lines and adult SD rats will be analyzed after BPA explore in different explore dose and time of BPA. The BPA-DNA adducts in cancer cell and normal cell will be compared. BPA-DNA adducts in urine, plasma, and tissues (eg. liver, kidney, and spleen) of SD rat will be detected by using this method to discover their metabolism and distribution in rat tissue. The relationship between DNA adducts content and exposed dose will also be investigated which is for screening and confirmation reliable marker of cancer. The obtained results will provide useful information for future investigation on BPA toxicities and the mechanism of toxicity of BPA. The content of BPA-DNA adducts in rat urine, plasma, and different tissues will be compared to know the metabolism and tissue distribution. Furthermore, the relationship between DNA adducts content and exposed dose will be investigated to screening and confirmation reliable marker of cancer. The obtained results will provide useful information the mechanism of toxicity of BPA and the relation between BPA and cancer risk.

双酚A（BPA）是一种广泛应用于塑料制造的化工原料，报道表明BPA可能增加癌症风险，但其机理尚不明确。DNA加合物是DNA化学损伤中最重要与最普遍的形式，可反映毒物到达靶位的实际接触剂量及DNA的损伤程度，对其分析有助于毒性机理的阐明。本项目拟建立基于质谱技术的快速、便捷、高通量、高灵敏度的BPA-DNA加合物的测定方法，并运用此方法分别分析4种不同细胞系及成年SD大鼠经不同剂量、不同时间的BPA暴露后所形成的BPA-DNA加合物。通过比较肿瘤细胞与正常细胞产生的BPA-DNA加合物的差异，探寻BPA可能的潜在致癌机理。通过BPA-DNA加合物在大鼠尿液、血液及不同组织中的形成情况，明确其在大鼠体内的组织分布和代谢情况。通过研究BPA-DNA加合物随BPA暴露时间、剂量的变化情况，筛选和确认可靠的肿瘤效应标志物，为BPA的毒性机理研究提供基础依据，为BPA与癌症风险相关性研究提供信息。

双酚A是一种广泛应用于塑料制造的化工原料，有文献称双酚A暴露可能会产生一些健康危害，比如增加癌症风险，但其机理尚不明确。本课题对双酚A等多种双酚类物质的质谱裂解规律进行了研究并建立了其在尿样等生物样品中的快速、高通量、高灵敏度的检测方法，运用高分辨质谱研究了双酚A的氧化代谢产物双酚A 3,4-醌与脱氧核糖核苷（DNA）/及核糖核苷（RNA）在体外的相互作用，发现DNA加合物的脱嘌呤比率比RNA加合物的更快。进一步运用超高效液相色谱-高分辨质谱建立了测定尿核苷的方法，并通过检测尿核苷（RNA代谢的终产物）来研究双酚A暴露诱导的氧化性RNA损伤，发现双酚A暴露和尿核苷之间存在剂量-反应关系。本课题还研究了双酚A 3,4-醌与不同的生物大分子（血红蛋白、人血清白蛋白和细胞色素c）的相互作用，运用基质辅助激光解吸/电离-飞行时间质谱等技术分析了双酚A 3,4-醌与蛋白之间的结合比例和结合位点，并通过运用高分辨率质谱双酚A 3,4-醌与2'-脱氧鸟苷、小牛胸腺DNA和乳腺癌细胞DNA的加合物结构，结果为双酚A醌代谢物与DNA共价结合提供了证据，为阐明双酚A醌加合物在生物系统和环境中的毒理学机制提供有价值的理论依据，为双酚A暴露的毒性研究提供了新的视角，并为双酚A与癌症等健康风险相关性研究提供信息。