Abstract：
Multiple sclerosis is an autoimmune disease that causes inflammatory damage to the central nervous system. At present, the pathogenesis of the disease is unknown. There is a lack of few effective therapy medications available. Therefore, it is necessary to further explore the pathogenesis of this illness and develop potential therapeutic drugs. Dabrafenib is potential therapeutic medicine for nervous system disease. In this study, we preliminarily studied the possible mechanism of dabrafenib in the treatment of multiple sclerosis from the perspective of ferroptosis. First, we observed that dabrafenib significantly improved symptoms of gait abnormalities, limb weakness or paralysis, and down-regulated levels of spinal cord inflammation in an experimental autoimmune encephalitis (EAE) model. Meanwhile, we also observed that dabrafenib could inhibit the proteins of ferroptosis in spinal cord tissue of EAE mice by Western blot. The results of immunohistochemical analysis showed that the effect of dabrafenib on ferroptosis mainly occurred in microglia. Second, dabrafenib was demonstrated to be able to inhibit the S phase of the cell cycle, reduce ROS levels, and reinstate mitochondrial activity in the LPS-induced BV2 inflammatory cell model. Futhermore, we found that dabrafenib inhibits P-JAK2 and P-STAT3 activation by acting Axl receptor, which in turn prevents neurogenic inflammation in microglia. The co-stimulated BV2 cell model with LPS and Erastin also verified these findings. Ultimately, the Axl knockout mice used to construct the EAE model allowed for the confirmation that dabrafenib prevented ferroptosis in microglia by up-regulating Axl receptor, which reduced the inflammatory demyelination associated with EAE. In summary, our research demonstrates the advantages of dabrafenib in multiple sclerosis treatment, which can prevent ferroptosis in microglia in multiple sclerosis through up-regulating Axl receptor, thus halting the progression of multiple sclerosis.
摘要：
多发性硬化症是一种自身免疫性疾病，可引起中枢神经系统的炎症损伤。目前,该病的发病机制尚不清楚。缺乏有效的治疗药物。因此,有必要进一步探讨该病的发病机制，并开发潜在的治疗药物。Dabrafenib是神经系统疾病的潜在治疗药物。在这项研究中,我们从铁凋亡的角度初步研究了达拉非尼治疗多发性硬化的可能机制。首先,我们观察到dabrafenib显着改善步态异常的症状，四肢无力或瘫痪，在实验性自身免疫性脑炎（EAE）模型中，脊髓炎症水平下调。同时,我们还通过westernblot观察到dabrafenib可以抑制EAE小鼠脊髓组织中的铁性凋亡蛋白。免疫组织化学分析结果表明，达拉非尼对铁细胞凋亡的影响主要发生在小胶质细胞中。第二,dabrafenib被证明能够抑制细胞周期的S期，降低ROS水平，并在LPS诱导的BV2炎症细胞模型中恢复线粒体活性。Futhermore,我们发现dabrafenib通过作用Axl受体抑制P-JAK2和P-STAT3的激活，从而防止小胶质细胞的神经性炎症。用LPS和Erastin共刺激的BV2细胞模型也证实了这些发现。最终,用于构建EAE模型的Axl敲除小鼠可以证实dabrafenib通过上调Axl受体来阻止小胶质细胞的铁性凋亡，这减少了与EAE相关的炎性脱髓鞘。总之,我们的研究证明了dabrafenib在多发性硬化症治疗中的优势，可以通过上调Axl受体来防止多发性硬化症小胶质细胞的铁凋亡，从而阻止多发性硬化症的进展。
