miR-146a激动剂对正畸复发过程牙周组织中炎症因子和IRAK1、TRAK6表达的影响

Effects of miR-146a Agonist on Expressions of Inflammatory Factors,IRAK1,and TRAK6 in Periodontal Tissues during Orthodontic Recurrence

目的:在正畸复发过程中,探究miR-146a对大鼠牙周组织中炎症相关基因的表达情况及相关信号通路的影响。方法:24只雄性SD大鼠,分为空白组(C组)和正畸牙齿移动模型组,模型组加力14 d后去除装置,并将其随机分为模型组(N组)、模型对照组(P组)、模型治疗组(T组);去除装置后,N组即刻处死取材,T组注射agomiR-146a,P组注射等量的阴性对照agomiR-control;连续注射7 d后取各组牙周组织,使用RT-PCR检测组织中miR-146a的表达情况,用RT-PCR和Western blot检测IRAK-1和TRAF6基因和蛋白的表达情况,用ELISA法检测牙周组织中IL-6、IL-1β、TNF-α的表达变化,用HE染色观察各组牙周组织形态学变化。结果:与C组比较,P组miR-146a的表达量明显下降(P<0.01),IRAK-1、TRAF6及炎症指标的表达均显著增加(P<0.01),且炎性细胞浸润增多,牙槽骨吸收;T组注射miR-146a激动剂后,miR-146a的表达量有所升高,IRAK-1、TRAF6及炎症指标的表达均显著降低(P<0.05),炎性细胞浸润减少,牙槽骨吸收减轻;而N组各个指标的表达没有明显变化(P>0.05)。结论:miR-146a激动剂可通过降低TRAF6和IRAK1的表达缓解由正畸复发导致的牙周组织炎症。

Objective:To investigate the effect of miR-146a on the expression of inflammation-related genes and related signaling pathways in periodontal tissues of rats during orthodontic recurrence.Methods:24 male SD rats were divided into normal control group(group C)and orthodontic tooth movement model group.Devices of the model group were removed after 14 days,with randomly divided into model group(group N),model control group(with agomiR-control,group P),and model treatment group(with agomiR-146a,group T).Group N was sacrificed immediately after the devices were removed.Group T was injected with agomir-146a and group P was injected with the same amount of negative control for 7 days.Periodontal tissues of each group were collected after 7 days.The expression of miR-146a in tissue was detected by RT-PCR.The genes and proteins expressions of IRAK-1 and TRAF6 were detected by RT-PCR and Western blot.The expression of IL-6,IL-1βand TNF-αin periodontal tissue were detected by ELISA.The changes of periodontal tissue morphology were observed by HE staining.Results:Compared with group C,the expression level of miR-146a in group P was significantly decreased and the difference was significant(P<0.01).The expressions of IRAK-1,TRAF6,and inflammatory indicators were significantly increased(P<0.01).The infiltration of inflammatory cells was increased and the absorption of alveolar bone was obvious.After the injection of miR-146a agonist in group T,the expression of miR-146a was increased,and the expression of IRAK-1,TRAF6,and inflammatory indicators were significantly reduced(P<0.05).The infiltration of inflammatory cells was less,and the absorption of alveolar bone was mild.However,there were no significant changes in the expression of each index in group N(P>0.05).Conclusion:miR-146a agonist can reduce the expression of TRAF6 and IRAK1 to relieve periodontal inflammation caused by orthodontic recurrence.