选择性雌激素受体调节剂对实验性自身免疫性脑脊髓炎小鼠的抗炎机制研究

Anti-inflammatory mechanism of selective estrogen receptor modulator in mice with experimental autoimmune encephalomyelitis

目的探讨选择性雌激素受体调节剂(SERM)减轻实验性自身免疫性脑脊髓炎(EAE)炎症反应的可能机制。方法用MOG35-55多肽诱发60只EAE小鼠模型,做去卵巢术。分为治疗组和对照组(n=30),治疗组予SERM(雷洛昔芬)治疗。比较2组EAE小鼠的临床症状评分。取脑和脊髓组织,行H-E染色、luxolfastblue(LFB)-H-E染色观察病理学改变;实时荧光定量PCR及ELISA法检测基质金属蛋白酶9(MMP-9)、肿瘤坏死因子α(TNF-α)、干扰素γ(IFN-γ)、白细胞介素4(IL-4)水平;蛋白质印迹分析检测髓鞘碱性蛋白(MBP)表达量,分析脱髓鞘情况。结果治疗组EAE小鼠与对照组相比,治疗组临床症状减轻(P<0.01)、发病率降低(P<0.05);H-E染色显示治疗组炎细胞浸润减少(P<0.05);LFB-H-E染色结果和MBP表达量显示治疗组脱髓鞘减轻(P<0.05);实时荧光定量PCR及ELISA结果示治疗组脑和脊髓组织中MMP-9、TNF-α、IFN-γ表达降低而IL-4增加(P<0.05,P<0.01)。结论 SERM可能通过降低MMP-9、TNF-α、IFN-γ表达,增加IL-4表达,从而减轻EAE小鼠炎症反应。

Objective To explore the anti-inflammatory mechanisms of selective estrogen receptor modulator （SERM） on experimental autoimmune encephalomyelitis（EAE）. Methods EAE models were induced with MOG35-55 peptide in 60 mice and all animals were ovarectomized. The model animals were then divided into treatment group and control group （n=30）. Treatment group was treated with SERM. The clinical symptom scores were compared between the two groups. The pathologic changes of the brain and spinal cord were studied by H-E staining and luxol fast blue（LFB）-HE staining. The expressions of MMP-9, TNF-α, IFN-γ, and IL-4 mRNA and protein were examined by quantitative real-time PCR and ELISA. Western blotting analysis was used to analyze the expression of myelin basic protein （MBP） so as to analyze the demyelination status.Results Clinical symptom scores and incidence of EAE in the treatment group were improved compared with those in the control group （P〈0.01, P〈0.05）. H-E staining showed that infiltration of inflammatory cells was decreased in the treatment group （P〈0.05）. LFB-H-E staining and Western blotting analysis showed that the demyelination was improved in the treatment group （P〈0.05）. The results of quantitative real-time PCR and ELISA showed that the expression of MMP-9,TNF-α, and IFN-γ were decreased and the expression of IL-4 was increased （P〈0.05, P〈0.01）. Conclusion SERM can alleviate the inflammation symptom in EAE mice through decreasing MMP-9, TNF-α, and IFN-γ and increasing IL-4 expression.