苯乙烯致DNA损伤及相关调控酶mRNA表达横断面研究

发布时间：2018-01-16 21:16

本文关键词：苯乙烯致DNA损伤及相关调控酶mRNA表达横断面研究　出处：《济南大学》2012年硕士论文　论文类型：学位论文

【摘要】：【研究目的】 1.了解职业苯乙烯工人接触水平及健康损害情况； 2.探讨苯乙烯对职业工人的遗传损伤效应； 3.以实时荧光定量为检测平台，探讨接触不同苯乙烯暴露水平对甲基转移酶、乙酰化酶mRNA表达的影响。寻找其职业危害的生物标志物，为职业接触人群的健康监护及危险度评价提供理论依据，达到加强病因预防的目的。【研究方法】 1.采用定点及个体采样获取不同暴露工人苯乙烯接触水平并通过苯乙烯作业工人职业卫生学调查及相应的职业健康体检，获取工人健康状况基础数据； 2.采用胞质分裂阻滞微核实验对不同暴露苯乙烯水平的作业工人进行细胞遗传毒性效应研究； 3.以SYBR Green I嵌合实时荧光定量聚合酶链式反应法检测相关DNA甲基转移酶DNMT1、DNMT3a、DNMT3b、组蛋白甲基化酶HMT和甲基CPG结合蛋白(MeCP2)以及蛋白乙酰转移酶HAT、组蛋白去乙酰酶HDAC的mRNA含量表达，探讨不同苯乙烯暴露工人对5种相关甲基转移酶和2种相关乙酰化酶mRNA表达，初步探讨表观遗传对相关调控酶的调控作用,寻找合适的生物标志物。【研究结果】 1.苯乙烯作业工人健康损害定点及个体检测显示苯乙烯接触工人均处于苯乙烯高暴露水平；暴露组工人咳嗽、头晕等症状的发生率明显高于对照组工人（P＜0.05），接触丙酮、稀料等其他有机溶剂是危险因素，其OR=8.920,95%CI(3.405,23.368）。两组临床体检结果如肝功、血常规、心电图、尿常规、肝胆肾B超检查等差异均无显著性（P＞0.05）。 2.苯乙烯对DNA损伤检测苯乙烯暴露组淋巴细胞微核率高于对照组，其DNA损伤程度差异有显著性(P＜0.05)，两组在性别间无差异（P＞0.05），未观察到吸烟、饮酒等因素对微核率有影响（P＞0.05）。 3.苯乙烯对甲基转移酶、乙酰化酶mRNA表达的影响苯乙烯暴露组DNA甲基转移酶DNMT1及组蛋白乙酰化酶HAT1mRNA高表达于对照组，差异显著（其P值分别为0.005,＜0.001），组蛋白甲基化酶HMT mRNA表达在两组间差异也具有统计学意义（P＜0.05）；DNA甲基转移酶DNMT3A、DNMT3B、甲基CPG结合蛋白MeCP2以及组蛋白去乙酰酶HDAC mRNA表达含量两组比较差异无统计学意义（P＞0.05）。在男性组中仅有HAT1的mRNA相对表达含量暴露组高于对照组，差异具有统计学意义（P＜0.001）；在女性组中DNMT1mRNA及HAT1mRNA的相对表达含量，暴露组明显高于对照组，具有显著性差异（P值分别为0.002，0.001），其他调控酶mRNA的表达差异不显著（P＞0.05）。【研究结论】 1.苯乙烯能够引起工人如咳嗽、头晕等症状的发生，并且在丙酮、稀料等有机溶剂的作用下会加剧机体反应程度。短年限暴露苯乙烯对工人的身体损伤不明显，其损伤效应还有待于继续观察。 2.苯乙烯暴露对人外周血淋巴细胞微核率有影响，并呈现一定的遗传毒性作用，双核微核可作为其早期遗传损伤的指标。 3.苯乙烯暴露可引起基因表达调控酶DNMT1、HMT及HAT1的mRNA不同程度的高表达，可作为其遗传损伤早期效应标志物，而对其他基因表达调控酶DNMT3a、DNMT3b、MeCP2及HDAC10的mRNA表达没有显著影响。HAT1mRNA在苯乙烯暴露的男性组、女性组中均高表达，DNMT1mRNA在女性苯乙烯暴露组中高表达，，其他调控酶如DNMT3a,DNMT3b, HMT, MeCP2及HDAC10的mRNA表达在不同性别暴露组没有显著影响。
[Abstract]:[purpose]
1. understand the occupational exposure level and health damage of occupational styrene workers.
2. to investigate the genetic damage effect of styrene on occupational workers.
3. by real-time fluorescent quantitative detection platform, to contact different styrene exposure level of methyl transferase, effect of acetyltransferase mRNA expression. The occupation harm biomarkers provide a theoretical basis for health monitoring and risk assessment for the occupation with people, to strengthen the etiology and prevention.
[research method]
1., the level of styrene exposure of different exposed workers was obtained by fixed point sampling and individual sampling, and the basic data of workers' health status were obtained through occupational hygienic investigation and occupational health examination of styrene workers.
The 2. study of the genotoxicity of cytokinesis block micronucleus test on different levels of workers exposed to styrene;
3. to detect DNA methyl SYBR Green I embedded real-time fluorescence quantitative polymerase chain reaction method transferase DNMT1, DNMT3a, DNMT3b, histone methyltransferase HMT and methyl CPG binding protein (MeCP2) and histone acetyltransferase HAT, histone deacetylase HDAC mRNA content of styrene exposed workers to investigate. 5 related methyltransferases and 2 related acetyltransferase mRNA expression, to explore the epigenetic regulation of genetic regulatory enzymes, to find suitable biomarkers.
[results]
Health damage of 1. styrene workers
Fixed point and individual test showed that styrene exposed workers styreneat high exposure level of workers exposed group; cough, dizziness and other symptoms were significantly higher than control group workers (P < 0.05), contact acetone and other organic solvents thinners and other risk factors, the OR=8.920,95% CI (3.405,23.368). Two groups of clinical examination results such as liver function. Blood routine, urine routine, ECG, liver and kidney were not significantly difference B ultrasound examination (P > 0.05).
Detection of DNA damage by 2. styrene
In the styrene exposure group, the lymphocyte micronucleus rate was higher than that in the control group, and the difference of DNA damage was significant (P < 0.05). There was no difference between the two groups in gender (P > 0.05). No smoking or drinking was observed on the micronucleus rate (P > 0.05).
Effect of 3. styrene on the expression of methyltransferase and acetyltransferase mRNA
Styrene exposure group DNA methyltransferase DNMT1 and histone deacetylase HAT1mRNA high expression in the control group, significant difference (P = 0.005, P < 0.001), histone methyltransferase HMT mRNA expression in the difference between the two groups was statistically significant (P < 0.05); DNA methyltransferase DNMT3A. DNMT3B, methyl CPG binding protein MeCP2 and histone deacetylase HDAC had no statistical significance mRNA expression content of the difference between the two groups (P > 0.05). In the male group only HAT1 of the relative expression of mRNA content in exposed group was higher than the control group, the differences were statistically significant (P < 0.001); in the female group and DNMT1mRNA the relative expression of HAT1mRNA in exposure group was significantly higher than the control group, with significant difference (P = 0.002,0.001), expression of other regulatory enzyme mRNA was not significant (P > 0.05).
[Conclusion]
1. styrene can cause workers such as cough, dizziness and other symptoms, and in acetone, thinners and other organic solvent under the action of the body will increase the degree of the reaction. The short period of workers exposed to styrene physical damage is not obvious, the damage effect remains to continue to observe.
2. styrene exposure has an effect on the micronucleus rate of human peripheral blood lymphocytes, and shows a certain genotoxic effect. Binuclear micronucleus can be used as an indicator of early genetic damage.
3. styrene exposure may induce gene expression regulation of enzyme DNMT1, the high expression of HMT and HAT1 mRNA in different degree, can be used as the genetic damage biomarkers of early, and regulate the expression of other genes enzymes DNMT3a, DNMT3b, MeCP2 and HDAC10 mRNA expression had no significant effect on.HAT1mRNA in male group styrene exposure, women groups the high expression of DNMT1mRNA in female styrene exposure high expression group, other regulatory enzymes such as DNMT3a, DNMT3b, HMT, MeCP2 and HDAC10 mRNA expression had no significant effect on gender differences in exposure group.

【学位授予单位】：济南大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R131

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