Development of Biological Safty Evaluation Used As An Indication of Gene Expression by Dental Resin Monomers

本研究的目的是建立牙科有机材料中的残留和淋溶物质以及具有药物代谢功能的新型内分泌干扰物敏感细胞系，并鉴定双酚A(BPA)表达的基因。将PC制成的正畸托槽浸泡在人的唾液中，将聚合调节剂双酚A、对叔丁基苯酚(t-BUP)和对-异丙基苯酚(p-CP)从托槽中浸出到唾液中。此外，当托槽浸泡在热变性唾液中时，BPA的浸出量高于浸入唾液的水平。残留的BPA、t-BUP和p-CP水平随着浸泡时间的延长而增加，提示浸泡在唾液中的托槽解聚为BPA和t-BUP或p-CP，这种解聚不涉及唾液中的酯酶和脂肪酶等酶。有必要用唾液来评估可浸出和残留的化学物质，很明显，人工唾液是在…中。使用唾液的替代品会更美味。从妊娠3.5d开始给予BPA 0.5、5、50和500 mg/kg/d的小鼠胎儿生殖器和经双酚A处理的T47D细胞中提取m-RNA，进行差异显示。尽管各对照组、BPA处理的细胞和小鼠之间存在差异，但只有NADH脱氢酶亚单位2被鉴定出来。由于给予双酚A的小鼠胸腺比对照组小，因此我们研究了双酚A对细胞因子产生的影响。高浓度的双酚A抑制细胞因子的产生，低浓度的双酚A则促进细胞因子的产生。通过分析双酚A对Jurkat人T细胞的影响，发现双酚A可引起细胞内钙离子浓度升高，并可使多种细胞内蛋白被双酚A磷酸化。采用集落形成实验和中性红实验研究了牙科树脂单体经细胞色素P3A4和细胞色素P3A7代谢后的细胞毒作用。每孔分别加入双酚A和双酚A甲基丙烯酸缩水甘油酯(Bis-GMA)和阳性对照阿普托品B1，培养7d。IC_&lt；50&gt；值的结果表明，与对照相比，这些单体不被CYP3A4或CYP3A7代谢激活。这些单体既不是CYP3A4和CYP3A7的激活剂，也不是抑制剂。经报告实验和Northan印迹分析，Bis-GMA、BAGE_2H_2O和BPA可诱导细胞色素P1A1的产生，而BAGE则抑制其诱导作用。然而，这种诱导作用随着3-甲基胆蒽的减少而显著增加。

The purpose of this reserch was to develop residual and leaching substances in dental organic materials as well as newly endocrine disrupter-sensitive cell lines with drug metabolizing function and to identify the gene expressed by bisphenol A(BPA). As orthodontic brackets made of PC, were immersed in human saliva, BPA as well as p-t-butylphenol(t-BuP) and p-cumylphenol(p-CP), which are polymerization regulatory agents,was leached from brackets into saliva. Furthermore, when brackets were immersed in heat-denatured saliva, the level of leached BPA was higher than those of saliva-immersion. Levels of residual BPA, t-BuP and p-CP was increased with the immersion time, suggesting that brackets immersed in saliva are depolymerized into BPA and t-BuP or p-CP and this depolymerization is not involve in enzymes in saliva such as esterases and lipases. There are necessary to evaluate the leachable and remaining chemical substances using saliva, and it is clear that the artificial saliva is ina … More dequate using alternatives of saliva. m-RNAs were extracted from T47D cells treated with BPA and fetal genital of mouse administered with 0.5, 5, 50 and 500 mg/kg/day of BPA from Day 3.5 of gestation and then the differential display was performed. Although there are differences between each controls and BPA-treated cell and mouse, only NADH dehydrogenase subunit 2 was identified. As thmus from mouse administered BPA is smaller than that of control, the effects of BPA on the production of cytokines were investigated. The producing ability of cytokines was inhibited by higher concentrations of BPA, whereas it was accelerated by lower concentrations of BPA. Analysing the effects of BPA on Jurkat human T cells, BPA was increased in concentrations of intracellular calcium ions pronto and various intracellular proteins were phosphorylated with BPA by SDS-PAGE examination. The cytotoxic effects of dental resin monomers after being metabolized by CYP3A4 and CYP3A7, using a colony formation assay and a neutral red assay were investigated. BPA and Bisphenol A glycidy1 methacrylate (Bis-GMA) and a positive control (Aflatoxine B1) were added separately to each well and cultured for 7 days. The resultant of IC_<50> values indicated that the monomers were not metabolically activated by CYP3A4 or CYP3A7 as compared to the control. These monomers act neither as activators nor as inhibitors of CYP3A4 and CYP3A7 Were confirmed. Analysing by reporter assay and Northan blot, Bis-GMA, BADGE 2H_2O and BPA induced CYP1A1 whereas BADGE inhibited its induction. However, this induction was markedly increased with 3-methylcholanthrene Less