Cuprizone诱导髓鞘损伤再生模型中Sip1的表达变化及其意义

The expression change of Sip1 and its implications in cuprizone-induced myelin injury and regeneration model

目的:研究Smad相互作用蛋白1(Sip1)在cuprizone诱导髓鞘损伤再生模型中的表达变化及其意义。方法:通过在饲料中掺入cuprizone喂食C57BL/6小鼠建立髓鞘损伤模型,利用黑金(black gold,BG)染色方法及Western Blot方法,检测髓鞘损伤模型是否建立成功;利用Western Blot方法检测在髓鞘损伤及再生过程中Sip1的表达情况。结果:BG染色方法检测到喂药6周后模型组小鼠与对照组相比,着色显著降低,Western Blot方法检测到模型组小鼠MOG(myelin oligodendrocyte glycoprotein)蛋白表达水平显著降低,GFAP(glial fibrillary acidic protein)蛋白表达水平显著增高,证明髓鞘损伤模型建立成功。在模型建立成功后,停止喂药,改用正常饲料喂养4周后,通过Western Blot检测到模型组小鼠MOG蛋白水平显著恢复,证明该阶段髓鞘已再生。利用Western Blot方法检测髓鞘损伤模型建立阶段及髓鞘再生阶段的Sip1蛋白水平,结果显示与对照组小鼠相比,在髓鞘损伤阶段,模型组小鼠的Sip1蛋白水平显著增加,在髓鞘再生阶段Sip1蛋白水平同样显著增加。结论:Sip1在髓鞘损伤再生过程中具有重要作用,本研究为Sip1作为治疗髓鞘相关疾病的靶点提供了理论依据。

Objective： To explore the function of Smad interacting protein Sipl and the alteration of its expression in cuprizone induced myelin injury and regeneration model. Methods： Cuprizone was orally delivered to C57B1/6 mice to induce myelin injury. Black gold （BG） staining and Western Blot were employed to examine the myelin injury. Sipl pro- tein level was examined by Western Blot. Results： After cuprizone treatment for 6 weeks, the BG staining significantly weakened, while the MOG protein expression decreased and GFAP protein expression increased, indicating that the myelin was injured by cuprizone treatment. Cuprizone feed was then stopped for 4 weeks to allow myelin regeneration. Western Blot result showsed that MOG protein level was significantly recovered, indicating the regeneration of myelin at this stage. We analyzed the expression level of Sipl at both stages of myelin injury and myelin regeneration, compared with control groups, and fond the Sip1 protein level significantly increased in both stages. Conclusion： Sipl may play a functional role in the process of demyelination and regeneration. Our study provides a potential target for the treatment of myelin related diseases.