H4K20me1与碱基切除修复相关基因在燃煤污染型砷中毒致DNA损伤修复中的作用  

Role of H4K20mel and base excision repair-related genes in repairing DNA damage induced by arsenic pollution through coal burning

作　　者：李军 谢琅 丁雪娇 王祺 梁冰 张爱华 

机构地区：[1]贵州医科大学环境污染与疾病监控教育部重点实验室、贵州医科大学公共卫生学院,贵州550025

出　　处：《中华地方病学杂志》2017年第11期781-786,共6页Chinese Journal of Endemiology

基　　金：国家自然科学基金（81360411、81430077）

摘　　要：目的了解燃煤污染型地方性砷中毒患者组蛋白H4第20位赖氨酸-甲基化（H4K20me1）修饰水平与碱基切除修复基因mRNA的转录水平，并分析其与DNA损伤的关系，为深入揭示砷致DNA损伤修复机制提供科学依据。方法收集贵州省兴仁县交乐村2014年自愿手术治疗的47例燃煤污染型砷中毒患者（-般病变组15例、癌前病变组14例、癌变组18例）及12例对照组的皮肤组织标本、头发样本和外周血样。电感耦合等离子质谱（ICP．MS）法测定发砷含量；免疫组化法检测皮肤组织中组蛋白H4K20me1修饰水平；实时荧光定量PCR检测外周血聚腺苷酸二磷酸核糖聚合酶-1（PARP1）、N-甲基化嘌呤-DNA．糖基化酶（MPG）、X射线修复交叉互补基因1（XRCC1）基因mRNA转录水平；单细胞凝胶电泳法检测外周血DNA损伤；酶联免疫吸附试验法检测外周血H4K20me1总体修饰水平。结果与对照组[中位数（第25～75百分位数）：0．15（0．07。0．23）μg／L]比较，砷中毒患者发砷含量[0．34（0．17-0．51）μg／L]明显升高（Z=6．037，P〈0．05）；与对照组（0．32±0．13、0．17±0．12）比较，癌变组患者外周血H4K20me1修饰水平（O．62±0．11）、癌前病变组和癌变组患者皮肤组织中H4K20me1修饰水平（0．54±0．20、0．83±0．10）明显增加（P〈0．05）；与对照组[0．95（0．50～1.49）、1．12（0．98-1．48）、0．96（0．67～1．17）]比较，癌变组PARP1、MPG基因mRNA表达[0．37（0．30～0．4J4）、0.38（O．15～0．48）]、癌前病变组和癌变组XRCC1基因mRNA表达[0．48（0_38～0．89）、0．32（0．20～0．55）]明显降低（P〈0．05）；与对照组（1．19±0．55、1．27±0．51）比较，-般病变组（6．49±0．98、6．60±1．11）、癌前病变组（11．22±1．40、10．07±1.11）和癌变组（20．38±1．72、27．01±1．78）彗星尾部DNA百分含量（Tai1DNA％）和彗星尾矩（OTM）�Objective To investigate the global level of histone 4 lysine 20 monomethylation （H4K20mel） and expression of base excision repair related mRNA in coal-burning-borne endemic arsenism patients and to analyze its relationship with DNA damage, in order to provide a scientific basis in deepening the interpretation of the role of arsenic in inhibiting repair of DNA damage. Methods In 2014, 47 hair samples, blood samples and skin tissue samples of the cases in Xingren County Guizhou Province were collected from the voluntary surgical treatment patients with endemic arsenism （15 general pathological change eases, 14 preeancerous cases and 18 cancerouscases） and 12 controls. The hair arsenic content was tested via the inductively coupled plasma-mass spectrometry method. The expression of histone H4K20mel in skin tissues was detected via the immunohistochemistry method; quantitative real-time polymerase chain reaction was used to detect the mRNA levels of poly （ADP-ribose） polymerase （PARP1）, N-methylation of purine-DNA-glycosylation （MPG） and X-ray repair cross complementary gene 1 （XRCC1）; and DNA damage in peripheral blood was detected by single cell gel electrophoresis test, the level of H4K20mel in peripheral blood cells was detected by using a sandwich enzyme-linked immunosorbent assay. Results Compared with the control group [median （25 - 75 percentile）： 0.15 （0.07 - 0.23） μg/L], the hair arsenic content in the case group [0.34 （0.17 - 0.51） μg/L] was significantly increased （Z = 6.037 ,P 〈 0.05）. Compared with the control group （0.32± 0.13, 0.17 ± 0.12）, the modification level of H4K20mel in peripheral blood with cancerous group （0.62 ± 0.11） was significantly increased, the modification levels of H4K20mel （0.54 ± 0.20, 0.83 ± 0.10） in skin tissues were increased in the precancerous group and cancerous group （P 〈 0.05）. Compared with the control group [0.95 （0.50 - 1.49）, 1.12 （0.98 - 1.48）, 0.96 （0.67 - 1.17）], the mRNA expression le

关 键 词：砷中毒 H4K20me1 DNA损伤修复 碱基切除修复基因 

分 类 号：R599.1[医药卫生—内科学]