Liu Yulan, Deng Shanshan, Song Zhibing, Zhang Qian, Guo Yuchen, Yu Yongsheng, Wang Yuliang, Li Tiejun, Megahed Fayed A K, Addissouky Tamer A, Mao Junqin, Zhang Yuefan
School of Medicine, Shanghai University, Shanghai, China.
Department of Pharmacy, The Air Force Hospital From Eastern Theater of PLA, Nanjing, China.
Front Pharmacol. 2021 Sep 7;12:725268. doi: 10.3389/fphar.2021.725268. eCollection 2021.
Monocyte locomotion inhibitory factor (MLIF) is a heat-stable pentapeptide from . Our previous study found that MLIF protects against ischemic stroke in rats and mice and exerts a neuroprotection effect in human neuroblastoma SH-SY5Y cells. Microglia/macrophage polarization has been proven to be vital in the pathology of ischemic stroke. Nevertheless, whether MLIF is able to modulate microglia/macrophage polarization remains unclear. We performed middle cerebral artery occlusion (MCAO) on C57BL/6J male mice and induced cultured BV2 microglia by oxygen-glucose deprivation (OGD), respectively. Immunfluorescence was utilized to detect the M1/2 markers, such as CD206 and CD16/32. qPCR and ELISA were used to detect the signature gene change of M1/2. The MAPK and NF-κB pathway associated proteins were measured by Western blot. To identify the protein target of MLIF, a pull-down assay was performed. We found that MLIF promoted microglia transferring from a "sick" M1 phenotype to a "healthy" M2 phenotype or . Furthermore, we proved that eukaryotic elongation factor 1A1 (eEF1A1) was involved in the modulation of microglia/macrophage polarization. Knocking down eEF1A1 by siRNA exhibited the M1 promotion effect and M2 inhibition effect. Taken together, our results demonstrated MLIF modulated microglia/macrophage polarization by targeting eEF1A1 in ischemic stroke.
单核细胞运动抑制因子（MLIF）是一种来自[具体来源未提及]的热稳定五肽。我们之前的研究发现，MLIF对大鼠和小鼠的缺血性中风具有保护作用，并在人神经母细胞瘤SH-SY5Y细胞中发挥神经保护作用。小胶质细胞/巨噬细胞极化已被证明在缺血性中风的病理过程中至关重要。然而，MLIF是否能够调节小胶质细胞/巨噬细胞极化仍不清楚。我们分别对C57BL/6J雄性小鼠进行大脑中动脉闭塞（MCAO），并通过氧糖剥夺（OGD）诱导培养的BV2小胶质细胞。利用免疫荧光检测M1/2标志物，如CD206和CD16/32。采用qPCR和ELISA检测M1/2的标志性基因变化。通过蛋白质免疫印迹法检测与丝裂原活化蛋白激酶（MAPK）和核因子κB（NF-κB）途径相关的蛋白。为了鉴定MLIF的蛋白靶点，进行了下拉试验。我们发现MLIF促进小胶质细胞从“病态”的M1表型转变为“健康”的M2表型[此处原文表述不完整]。此外，我们证明真核延伸因子1A1（eEF1A1）参与了小胶质细胞/巨噬细胞极化的调节。通过小干扰RNA（siRNA）敲低eEF1A1表现出促进M1和抑制M2的作用。综上所述，我们的结果表明，在缺血性中风中，MLIF通过靶向eEF1A1调节小胶质细胞/巨噬细胞极化。
