薯蓣皂苷对实验性变态反应性脑脊髓炎模型小鼠损伤的保护作用及机制研究

目的:探讨薯蓣皂苷治疗实验性变态反应性脑脊髓炎(EAE)的效果及其可能机制.方法:40只成年雌性C57BL/6小鼠随机分为对照组、模型组和薯蓣皂苷低、高剂量组,以髓鞘碱性蛋白+完全弗氏佐剂构建EAE小鼠模型.LFB和HE染色观察髓鞘和浸润细胞;免疫荧光染色检测T细胞活化标志物(CD4)、巨噬细胞活化标志物(F4/80)...

Study on the Protective Effect and Mechanism of Dioscin on the Injury of Experimental Allergic Encephalomyelitis in Mice

Objective:To investigate the effect of dioscin on experimental allergic encephalomyelitis(EAE)and its possible mechanism.Methods:A total of 40 adult female C57 BL/6 mice were randomly divided into control group,model group and dioscin low-dose group and dioscin high-dose group.EAE models were constructed with myelin basic protein and complete Freund’s adjuvant.LFB and HE staining were used to observe the iliac sheath and infiltrating cells.Immunofluorescence staining was used to detect the expression of T cell activation markers(CD4),macrophage activation markers(F4/80),astrocyte markers(GFAP)and microglia marker(IBA-1).The expression levels of IFN-γ,IL-17,IL-22,IL-4 and NLRP3 in serum were detected by ELISA.The expression levels of NF-κB,p-NF-κB(nucleus and cytoplasm),IFN-γ,IL-17,IL-22,IL-4 and NLRP3 in spinal cord were detected by Western blotting.The activity of NF-κB was detected by Trans AMTM NF-κB p65 assay kit.Results:Compared with the control group,the expressions of CD4,F4/80,GFAP and IBA-1 in the spinal cord of the model group were significantly increased(P<0.05).Compared with the model group,the expressions of CD4,F4/80,GFAP and IBA-1 in the dioscin low and high-dose groups were significantly decreased(P<0.05).Compared with the control group,the protein expression levels of IFN-γ,IL-17,IL-22 and NLRP3 in serum and spinal cord tissue of the model group were significantly increased,while the level of IL-4 was significantly decreased(P<0.05).The protein expression levels of IFN-γ,IL-17,IL-22 and NLRP3 in the dioscin low and high-dose groups were significantly lower than those in the model group,while the level of IL-4 was significantly higher than that in the model group in a dose-dependent manner(P<0.05).Compared with the control group,NF-κB in the cytoplasm of spinal cord was significantly decreased and NF-κB in the nucleus was significantly increased in the model group(P<0.05).Compared with the model group,NF-κB in bone marrow cytoplasm was significantly increased and NF-κB in nucleus was significantly decreased in the dioscin low and high-dose groups(P<0.05).Compared with the control group,the binding activity of nuclear NF-κB p65 to DNA in the model group was significantly increased(P<0.05).The binding activity of nuclear NF-κB p65 to DNA in the dioscin low and high-dose groups was significantly lower than that in the model group(P<0.05).Conclusion:Dioscin may improve the expression of inflammatory factors in peripheral blood and spinal cord by inhibiting the activation of p-NF-κB,thereby improving the pathological injury of spinal cord in EAE mice.