摘要
目的观察N-乙酰半胱氨酸(N-acetylcysteine,NAC)对哮喘模型小鼠自然调节性T细胞(natural regulatory T cells,nTreg)/辅助性T细胞17(T helper cell 17,Th17)(nTreg/Th17)失衡的影响,并探讨其起效机制。方法 50只6周龄SPF级BALB/c小鼠随机分为对照组、模型组、NAC低剂量组、NAC中剂量组、NAC高剂量组5个组,每组10只。模型组、NAC低剂量组、NAC中剂量组、NAC高剂量组采用卵清蛋白致敏及激发制备哮喘小鼠模型,并制备T细胞悬液。NAC低剂量组、NAC中剂量组、NAC高剂量组小鼠分别按照50μg/kg、100μg/kg、200μg/kg体重给予NAC灌胃(浓度50μg/ml),每天1次,7d为1个疗程,治疗1个疗程。疗程结束后,RT-PCR法检测叉状头螺旋转录因子3(forkhead helix transcription factor 3,FOXP3)mRNA、维A酸相关孤独受体(retinoid-ralated orphan receptorγt,RORγt)mRNA表达水平;ELISA法检测白细胞介素17(interleukin 17,IL-17)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞介素1β(interleukin 1β,IL-1β)、白细胞介素6(interleukin 6,IL-6)、白细胞介素10(interleukin 10,IL-10)水平;苏木精-伊红染色法观察肺组织病理形态变化。结果和对照组比较,模型组IL-17、TNF-α、IL-1β和IL-6水平均升高而IL-10水平降低,FOXP3mRNA相对表达量下降而RORγt mRNA相对表达量升高,差异均有统计学意义(P<0.01或P<0.05);和模型组比较,NAC中剂量组、NAC高剂量组IL-17、TNF-α、IL-1β和IL-6水平均降低而IL-10水平升高,FOXP3mRNA相对表达量升高而RORγt mRNA相对表达量下降,差异均有统计学意义(P<0.01或P<0.05)。结论NAC促进FOXP3基因表达,减少RORγt基因表达,抑制Th17的分化,纠正nTreg/Th17失衡是NAC在哮喘治疗中缓解炎症的作用环节之一。
Objective To explore the effects of N-acetylcysteine（NAC）on natural regulatory T cells（nTreg）/T helper cell 17（Th17）imbalance in mice model of asthma and to discuss its therapeutic mechanism.Methods Six weeks old with SPF grade BALB/c mice were randomly divided into 5 groups：a control group,a model group,a NAC low-dose group,a NAC middle-dose group and a NAC high-dose group,with 10 mice in each group.Mouse asthma models of the model group,of the NAC low-dose group,of the NAC middle-dose group and of the high-dose group were established with ovalbumin（OVA）sensitization and stimulating,and T cell suspensions were prepared.The low-dose,middle-dose,high-dose groups were intragastrically administrated with 50μg/ml NAC according to body weights of 50μg/kg,of 100μg/kg and of 200μg/kg,respectively,once a day for a treatment course of seven days.After a therapeutic course was finished,we detected the expressions of forkhead helix transcription factor 3（FOXP3）mRNA and retinoid-related orphan receptorγt（RORγt）mRNA by the method of RT-PCR,the IL-17,TNF-α,IL-1β,IL-6 and IL-10 levels were detected by the method of ELISA and the lung tissue morphological features were observed by hematoxylin-eosin staining. Results Compared with the control group,in the model group the levels of IL-17,of TNF-α,of IL-1β,of IL-6 and the expression of RORγt mRNA increased while the IL-10 level and the FOXP3 mRNA expression reduced,there were all statistically significant differences（P〈0.01 or P〈0.05）.Compared with the model group,in the NAC middle-dose group and the NAC high-dose group the IL-17,TNF-α,IL-1β,IL-6 levels and the expression of RORγt mRNA reduced while the level of IL-10 and the expression of FOXP3 mRNA increased,there were all statistically significant differences（P〈0.01 or P〈0.05）. Conclusion NAC enhances the expression of FOXP3 mRNA while reduces the expression of RORγt mRNA and inhibits the differentiation of Th17,then,the nTreg/Th17 balance is recovered,which is one of the
出处
《右江民族医学院学报》
2017年第6期440-443,共4页
Journal of Youjiang Medical University for Nationalities
基金
广西自然科学基金青年基金资助项目(2015GXNSFBA139159)
