5-氮杂胞苷对变应性鼻炎大鼠DNA甲基转移酶1基因调节作用的机制研究

Study on the mechanism of 5-azacytidine on DNA methyltransferase 1 gene in allergic rhinitis rats

目的探究甲基化酶抑制药5-氮杂胞苷(5-aza)对DNA甲基转移酶1(DNMT1)的调控作用。方法将大鼠分为正常组、模型组和实验组。正常组大鼠不做干预;模型组大鼠通过腹腔注射卵清蛋白(OVA)和Al(OH)3及OVA局部致敏方法建立变应性鼻炎(AR)模型;实验组大鼠建模后用5 mg·kg^(-1)5-aza进行干预处理。用酶联免疫吸附试验检测大鼠血清免疫球蛋白E(IgE)表达水平;用实时荧光定量聚合酶链反应法检测大鼠DNMT1 mRNA表达情况;用蛋白质印迹法检测大鼠DNMT1蛋白表达情况。结果正常组、模型组和实验组大鼠血清IgE表达水平分别为0.066±0.002、0.074±0.002和0.073±0.003;DNMT1 mRNA的表达水平分别为1.00±0.07、3.92±0.82和0.55±0.16;DNMT1蛋白表达水平分别为0.77±0.13、1.16±0.22和0.40±0.10。模型组的上述指标与正常组比较,差异均有统计学意义(均P<0.01);实验组的上述指标与模型组比较,差异均有统计学意义(均P<0.01)。结论5-aza作为DNA甲基化转移酶抑制药可以通过调控DNMT1表达参与AR大鼠的发生发展。

Objective To explore the regulation of methylase inhibitor 5-azacytidine(5-aza)on DNA methyltransferase 1(DNMT1).Methods The rats were divided into normal group,model group and experimental group.The rats in the normal group were not intervened;the model group were injected intraperitoneally with ovalbumin(OVA)and Al(OH)3 and sensitized locally with OVA,allergic rhinitis(AR)rat models were established;after modeling,rats in experimental group were treated with 5 mg·kg^(-1)5-aza intervention.The level of serum immunoglobulin E(IgE)expression was detected by enzyme linked immunosorbent assay;the expression of DNMT1 mRNA was detected by real time quantitative polymerase chain reaction;the expression of DNMT1 protein was detected by Western blot.Results The expression levels of serum IgE in normal group,model group and experimental group were 0.066±0.002,0.074±0.002 and 0.073±0.003,respectively;the expression levels of DNMT1 mRNA in normal group,model group and experimental group were 1.00±0.07,3.92±0.82 and 0.55±0.16,respectively;the expression levels of DNMT1 protein were 0.77±0.13,1.16±0.22 and 0.40±0.10,respectively.The above indexes in model group were significantly different from those in normal group(all P<0.01);the above indexes in experimental group were significantly different from those in model group(all P<0.01).Conclusion As an inhibitor of DNA methyltransferase,5-aza can participate in the occurrence and development of AR rats by regulating the expression of DNMT1.