环孢素对系统性红斑狼疮模型小鼠的肾保护作用及其机制研究

Study on Protective Effect of Cyclosporine on Renal Tissue of Systemic Lupus Erythematosus Model Mice and Its Mechanism

目的:研究环孢素对降植烷诱导的系统性红斑狼疮(SLE)模型小鼠的肾保护作用及其机制。方法:选取雌性BALB/c小鼠,一次性腹腔注射降植烷0.5 m L以建立SLE模型,检测小鼠尿蛋白、抗双链DNA(ds-DNA)抗体水平以验证模型是否成功建立。6个月后,取造模成功的小鼠40只,随机分为模型组、阳性对照组(泼尼松,5 mg/kg)和环孢素高、低剂量组(30、10 mg/kg),另取10只未造模小鼠作为正常对照组(生理盐水),每天1次灌胃给药,每周5次,连续给药18周。采用酶联免疫吸附法检测小鼠血清中抗ds-DNA抗体、免疫球蛋白G(IgG)、免疫球蛋白M(IgM)等免疫指标水平和肿瘤坏死因子α(TNF-α)、白细胞介素6(IL-6)、干扰素γ(IFN-γ)等炎症因子水平;采用生物化学法检测24 h尿蛋白和血清中肌酐(Cr)、尿素氮(BUN)水平;采用苏木精-伊红染色法观察肾组织病理变化;采用免疫组化法考察肾组织中IgG免疫复合物沉积情况;采用逆转录-聚合酶链反应法检测肾组织中p38丝裂原活化蛋白激酶(p38MAPK)、肿瘤坏死因子样弱凋亡诱导物(TWEAK)mRNA的表达水平。结果:与正常对照组比较,模型组小鼠血清中抗ds-DNA抗体、IgG、IgM、TNF-α、IL-6、IFN-γ、Cr、BUN和24 h尿蛋白水平均显著升高(P<0.05);肾组织出现明显病理变化,IgG免疫复合物表达水平显著增加(P<0.05);肾组织中p38MAPK、TWEAK mRNA的表达水平均显著升高(P<0.05)。与模型组比较,环孢素高剂量组小鼠血清中抗ds-DNA抗体、IgG、IgM、TNF-α、IL-6、IFN-γ、Cr、BUN和24 h尿蛋白水平,环孢素低剂量组小鼠血清中抗ds-DNA抗体、IgG、BUN水平均显著降低(P<0.05);环孢素高、低剂量组小鼠肾组织病理变化均明显减轻,IgG免疫复合物表达水平均显著降低(P<0.05);环孢素高剂量组小鼠肾组织中p38MAPK、TWEAK mRNA的表达水平,环孢素低剂量组小鼠肾组织中TWEAK m RNA的表达水平均显著降低(P<0.05)。结论:环孢素对降植烷致SLE模型小鼠有一定的肾组织保护作用,对其肾损伤有一定改善作用,其作用机制可能与抑制TWEAK-p38MAPK信号通路有关。

OBJECTIVE:To study the protective effects of cyclosporine on renal tissue of pristine-induced systemic lupus erythematosus(SLE)model mice and its mechanism.METHODS:Female BALB/c mice was given pristine 0.5 mL intraperitoneally to establish SLE model.The levels of urine protein and anti-ds-DNA antibody were detected to validate model establishment.6 months later,40 model mice were randomly divided into model group,positive control group(prednisone,5 mg/kg),cyclosporine high-dose and low-dose groups(30,10 mg/kg),once a day,5 times a week,for consecutive 18 weeks.Another 10 un-modeled mice were included in normal control group and given normal saline intragastrically.The serum levels of immunological indexes as anti-ds-DNA antibody,IgG,IgM and inflammatory factors such as TNF-α,IL-6 and IFN-γwere detected by ELISA.24 h urine protein and serum creatinine(Cr),urea nitrogen(BUN)levels were measured by biochemical method.The pathological changes of renal tissues were observed by HE staining.Immunohistochemistry was used to survey IgG immune complexes deposition in renal tissues.mRNA expression of p38MAPK and TWEAK were detected by RT-PCR.RESULTS:Compared with normal control group,the serum levels of anti-ds-DNA,IgG,IgM,TNF-α,IL-6,IFN-γ,Cr,BUN and 24 h urine protein in mice were significantly increased in model group(P<0.05);obvious pathological changes were observed in renal tissue and the expression level of IgG immune complex increased significantly(P<0.05);the mRNA expression levels of p38MAPK and TWEAK in renal tissue were increased significantly(P<0.05).Compared with model group,the serum levels of anti-ds-DNA,IgG,IgM,TNF-α,IL-6,IFN-γ,Cr,BUN and 24 h urine protein were significantly decreased in cyclosporine high-dose group,and the serum levels of anti-ds-DNA,IgG and BUN were also significantly decreased in cyclosporine low-dose group(P<0.05);the pathological changes of renal tissue were relieved significantly in cyclosporine high-dose and low-dose groups,and expression levels of IgG immune complex were decreased significantly(P<0.05);the mRNA expression levels of p38MAPK and TWEAK in renal tissue were decreased significantly in cyclosporine high-dose group,and those of TWEAK were also decreased significantly in cyclosporine low-dose group(P<0.05).CONCLUSIONS:Cyclosporine has certain protective effect on renal tissue of pristine-induced SLE model mice and can relieve renal injury to certain extent,which may be associated with inhibiting TWEAK-p38MAPK signaling pathway.