Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
Neuroscience Research Center, Iran University of Medical Sciences, Poursina Street, 1417613151, Tehran, Iran.
J Mol Histol. 2019 Jun;50(3):263-271. doi: 10.1007/s10735-019-09824-0. Epub 2019 Apr 23.
Oxidative stress with mitochondrial defects has a central role in the development and deterioration of Multiple sclerosis (MS). According to new findings of the effects of metformin on mitochondrial function, has attracted a lot of attention. Furthermore, it is suggested that metformin exerts its beneficial influence through AMP-activated protein kinase (AMPK) pathway. In the current study, we investigated the possible protective effects of metformin on oxidative stress and mitochondrial function by activating the AMPK pathway in the cuprizone-induced demyelination. Mice were fed with cuprizone for 6 weeks. Animals simultaneously received metformin. After sacrificing animals, myelinations, and gliosis, changes in transcription factor and biochemical analysis were assessed. Transmission electron microscopy and luxol fast blue staining revealed that the myelinated axons within corpus callosum of cuprizone-induced demyelination animals increased after administration of metformin. Metformin also upregulated the expression of mitochondrial biogenesis genes. Furthermore, the biochemical analysis demonstrated that metformin ameliorated the oxidative stress induced by cuprizone. Immunohistochemistry analysis showed that astrogliosis and microgliosis were decreased after metformin administration while it enhanced the number of oligodendrocytes. Our data implicated that metformin exerts its therapeutic effects on MS by AMPK signaling improved mitochondrial homeostasis and protected oligodendrocytes.
氧化应激和线粒体缺陷在多发性硬化症(MS)的发展和恶化中起着核心作用。根据二甲双胍对线粒体功能影响的新发现,引起了广泛关注。此外,有人认为二甲双胍通过 AMP 激活的蛋白激酶(AMPK)通路发挥其有益影响。在本研究中,我们通过激活 cuprizone 诱导的脱髓鞘模型中的 AMPK 通路,研究了二甲双胍对氧化应激和线粒体功能的可能保护作用。用 cuprizone 喂养小鼠 6 周。同时给予动物二甲双胍。处死动物后,评估髓鞘和神经胶质增生、转录因子变化和生化分析。透射电镜和卢索快速蓝染色显示,给予二甲双胍后,胼胝体中 cuprizone 诱导的脱髓鞘动物的有髓轴突增加。二甲双胍还上调了线粒体生物发生基因的表达。此外,生化分析表明,二甲双胍改善了 cuprizone 诱导的氧化应激。免疫组化分析表明,二甲双胍给药后星形胶质细胞和小胶质细胞减少,少突胶质细胞增多。我们的数据表明,二甲双胍通过 AMPK 信号改善线粒体稳态和保护少突胶质细胞发挥其对 MS 的治疗作用。