【摘要】 [目的]了解燃煤污染型氟中毒人群外周血中DNA甲基化转移酶1(DNA methylation transferase 1,DNMT1)m RNA转录及蛋白表达情况,探讨其在氟中毒致病机制中的作用。[方法]在知情同意原则下,采集贵州省燃煤污染型氟中毒病区某县的调查对象尿液样本,采用氟离子电极法测定尿氟含量并依据尿氟含量将调查对象(380例)分为正常尿氟(尿氟<1.96 mg/g Cr)组(140例)、低氟(1.96 mg/g Cr≤尿氟<3.92 mg/g Cr)组(93例)、中氟(3.92 mg/g Cr≤尿氟<7.84 mg/g Cr)组(82例)、高氟(尿氟≥7.84 mg/g Cr组(65例);采用实时荧光定量PCR(FQ-PCR)法检测外周血中DNMT1 m RNA转录;采用酶联免疫吸附(ELISA)法检测外周血中DNMT1蛋白表达。[结果]调查对象外周血中DNMT1 m RNA转录,各组间差异具有统计学意义(F=3.125,P<0.05);进一步两两比较分析发现,低、中氟组DNMT1 m RNA转录高于正常尿氟组(P<0.05),且低氟组DNMT1 m RNA转录高于中、高氟组(P均<0.05)。调查对象外周血中DNMT1蛋白表达,各组间差异有统计学意义(F=3.113,P<0.05);进一步两两比较分析发现,低氟组DNMT1蛋白水平高于正常尿氟组(P<0.05),且低氟组DNMT1蛋白水平高于高氟组(P<0.05)。[结论]DNMT1参与氟中毒的发生发展过程,其转录及蛋白表达增强可能是氟骨症发生的早期分子事件。更多还原

【Abstract】 [Objective] To investigate the DNA methylation transferase 1(DNMT1) transcription and protein expression in peripheral blood of patients with endemic fluorosis induced by coal burning, and explore the role of DNMT1 in fluorosis pathogenesis. [Methods] Following the principle of informed consent, urine samples were collected from 380 individuals residing in a coal-burning endemic fluorosis area of Guizhou. Urinary fluorine(UF) content was determined by fluoride ion selective electrode, according to which the investigated individuals were stratified into normal(UF<1.96 mg/g Cr, 140 cases), low(1.96 mg/g Cr≤UF<3.92 mg/g Cr, 93 cases), medium(3.92 mg/g Cr ≤ UF<7.84 mg/g Cr, 82 cases), and high UF groups(UF≥ 7.84 mg/g Cr, 65 cases). The m RNA transcription of DNMT1 was detected by real-time fluorescent quantitative polymerase chain reaction(FQ-PCR). The DNMT1 protein was detected by enzyme linked immune sorbent assay(ELISA). [Results] The transcription levels of DNMT1 m RNA in respondents’ peripheral blood samples significantly varied among the groups(F=3.125, P < 0.05). The results of pairwise comparison found that the low and middle UF groups presented higher expression of DNMT1 m RNA transcription than the normal UF group(P < 0.05); the low UF group also showed higher expression of DNMT1 m RNA transcription than the medium and high fluoride exposure groups(P < 0.05). The contents of DNMT1 protein in respondents’ peripheral blood samples were different among the groups(F=3.113, P < 0.05). The results of pair-wise comparison showed that the low UF group presented higher DNMT1 protein content than the normal UF group and the high UF group(P < 0.05). [Conclusion] The elevated DNMT1 expression of its transcription and protein is involved in the fluorosis pathogenesis and could be early molecular events of fluorosis.更多还原