Mdivi-1对cuprizone诱导的脱髓鞘性病变小鼠少突胶质细胞的保护作用

Mdivi-1 protects oligodendrocytes in cuprizone-induced demyelinating disease model in mice

目的:探讨线粒体分裂抑制剂1(Mdivi-1)对cuprizone诱导的脱髓鞘性病变模型小鼠少突胶质细胞损伤的作用及其机制。方法:将8周龄雄性C57BL/6小鼠用含0. 2%cuprizone的饲料饲喂,制备脱髓鞘性病变模型。将小鼠随机分为DMSO正常组(腹腔注射DMSO+饲喂正常饲料)、cuprizone模型组(饲喂含cuprizone的饲料)、DMSO+cuprizone模型组(腹腔注射DMSO+饲喂含cuprizone的饲料)和Mdivi-1干预组(腹腔注射Mdivi-1+饲喂含cuprizone的饲料)。通过固蓝染色及PLP、p-Drp1(Ser616)、CFB、C1q、C3b和C5b-9的免疫荧光染色实验检测Mdivi-1对髓鞘和少突胶质细胞的保护作用。结果:饲喂含cuprizone的饲料42 d可成功诱导小鼠脱髓鞘性病变模型,导致大脑胼胝体区髓鞘丢失,诱导Drp1磷酸化水平升高及C1q和CFB补体途径激活,并导致攻膜复合体在少突胶质细胞上组装。给予Mdivi-1可明显减少髓鞘丢失,抑制补体激活和攻膜复合体在少突胶质细胞的组装。结论:Mdivi-1干预可缓解cuprizone诱导的小鼠脱髓鞘病理学改变,其机制可能与抑制补体激活替代途径有关。

AIM:To evaluate the effect of mitochondrial division inhibitor 1(Mdivi-1)on cuprizone-induced demyelinating disease model and the possible mechanism.METHODS:The demyelinating disease model in 8-week-old male C57BL/6 mice was induced by feeding with the diet containing 0.2%cuprizone.The mice were randomly divided in⁃to DMSO+normal group(intraperitoneally injected with DMSO and fed with normal diet),cuprizone group(fed with cupri⁃zone-containing diet),DMSO+cuprizone group(intraperitoneally injected with DMSO and fed with cuprizone-containing diet),and Mdivi-1+cuprizone group(intraperitoneally injected with Mdivi-1 and fed with cuprizone-containing diet).Luxol fast blue(LFB)staining and immunofluorescence staining were performed to evaluate the protective effect of Mdivi-1 on myelin and oligodendrocytes.RESULTS:The mice fed with cuprizone-containing diet for 42 d had dramatic myelin loss as evaluated by LFB staining and immunofluorescence staining for PLP.The phosphorylation of Drp1(Ser616)and the positive signal of C1q,CFB,C3b and C5b-9 were significantly increased in DMSO+cuprizone group compared with DMSO+normal group.However,Mdivi-1 treatment significantly protected oligodendrocytes from damage,and inhibited Drp1 phosphorylation and CFB,C3b and C5b-9 activation on oligodendrocytes in the corpus callosum area of the brain.CONCLUSION:Mdivi-1 may exert a neuroprotective effect by anti-complement reaction to arrest the progression of de⁃myelination induced by cuprizone.