miR-7抑制剂治疗MRL/lpr小鼠的实验性研究

Experimental study of miR-7 antagomir in treatment of MRL/lpr mice

目的:探讨miR-7抑制剂治疗MRL/lpr小鼠的疗效。方法:选取30只MRL/lpr小鼠,随机分为miR-7抑制剂(miR-7 antagomir)组、环磷酰胺(CTX)组和生理盐水(Saline)对照组,10只/组。MRL/lpr小鼠13周时开始治疗,以上药物分别连续给药5周。每周观察各组小鼠一般状况并称重,留取血清和尿液标本。ELISA检测13~17周三组小鼠血清ANA、抗ds-DNA抗体、C3水平,并检测上述各周三组小鼠尿蛋白水平。流式细胞术检测三组小鼠Tfh细胞比例变化。RT-PCR检测三组小鼠脾脏和淋巴结miR-7和PTEN mRNA表达水平。HE、PAS、PASM染色观察光镜下三组小鼠的肾脏病理情况。结果:治疗5周后,形态学方面:与Saline组相比,miR-7 antagomir组和CTX组小鼠一般状况良好,体质量随周龄增加而增加。血清学方面:miR-7 antagomir组和CTX组血清ANA和抗ds-DNA抗体较Saline组明显下降,补体C3水平明显上升,但两治疗组间上述指标差异均无统计学意义。细胞学方面:miR-7 antagomir组小鼠脾脏Tfh细胞比例明显低于Saline组。与Saline组比较,miR-7 antagomir组小鼠脾B细胞miR-7表达水平降低,PTEN mRNA表达水平升高。此外,miR-7 antagomir组和CTX组小鼠光镜下肾脏病理改变均较Saline组有所好转,但该两组间肾脏病理改变无明显差异。结论:miR-7可作为系统性红斑狼疮的潜在治疗靶点,miR-7 antagomir能够显示出与经典免疫抑制剂CTX相近的治疗效果,有效地改善了MRL/lpr小鼠的狼疮样疾病表现,延缓了病情进展。

Objective:To investigate the efficacy of miR-7 antagomir in treatment of MRL/lpr mice.Methods:Thirty MRL/lpr mice were selected and randomly divided into miR-7 antagomir group,CTX group and Saline control group,with 10 mice in each group.MRL/lpr mice were treated at 13 weeks,and the above drugs were administered continuously for 5 weeks.General condition of the mice in each group was observed weekly and weighed,and serum and urine samples were collected.Serum ANA,anti-ds-DNA antibody and C3 levels of mice in the 13~17 weeks of three groups were detected by ELISA,and urinary protein level of mice in the above three groups were detected at every week.Changes in proportion of Tfh cells in the three groups of mice were detected by flow cytometry.RT-PCR was used to detect expression levels of miR-7 and PTEN mRNA in spleen and lymph nodes of three groups of mice.Pathological conditions of kidneys of three groups of mice were observed under light microscope by HE,PAS,PASM staining.Results:After 5 weeks of treatment,in terms of gross morphology:Compared with Saline group,mice in miR-7 antagomir group and CTX group were in good general condition,and their body weight were increased with the increased age.In terms of serology:Serum ANA and anti-ds-DNA antibody of miR-7 antagomir group and CTX group were significantly lower than those of Saline group,while level of complement C3 was significantly increased,there was no statistical difference in the above indicators between the two treatment groups.In terms of cytology:Proportion of Tfh cells in spleen of mice in miR-7 antagomir group was significantly lower than that in Saline group.Compared with Saline group,expression level of miR-7 in spleen B cells of mice in miR-7 antagomir group was decreased,while expression level of PTEN mRNA was increased.In addition,pathological changes of kidneys of mice in miR-7 antagomir group and CTX group were improved compared with Saline group,there was no significant difference in pathological changes of kidneys between the two groups.Conclusion:miR-7 can be used as a potential target for treatment of systemic lupus erythematosus,miR-7 antagomir can show similar therapeutic effects as the classical immunosuppressant CTX,effectively improve the lupus-like disease manifestations in MRL/lpr mice and delay the progression of the disease.