miR-155 敲低通过靶向 MafB 保护脑缺血再灌注损伤。
miR-155 Knockdown Protects against Cerebral Ischemia and Reperfusion Injury by Targeting MafB.
机构信息
Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China.
Department of Neurology, Luoyang Central Hospital Affiliated to Zhengzhou University, Luoyang, Henan, China.
出版信息
Biomed Res Int. 2020 Jan 21;2020:6458204. doi: 10.1155/2020/6458204. eCollection 2020.
BACKGROUND
Studies have elucidated that the variable expression levels of miRNAs influence the inflammatory process in ischemic stroke. Nevertheless, the impact and potential mechanism of miR-155 in cerebral ischemia-reperfusion injury (CIRI) keep to be incompletely known.
METHODS
The levels of miR-155 and MafB were determined via qRT-PCR, western blot, or immunohistochemistry assays in plasma of patients with CIRI, oxygen glucose deprivation/reoxygenation (OGD/R) induced SH-SY5Y cells, and mouse models with middle cerebral artery occlusion (MCAO). The association between miR-155 and MafB was validated via dual-luciferase reporter and western blot assays. Cell viability, apoptosis, invasion, and migration were evaluated through MTT, flow cytometry, Transwell and wound healing assays. Infarction volume was measured in MCAO mouse brain tissues by TTC assay. The expression of inflammatory mediators was measured by ELISA in cells and brain tissues.
RESULTS
miR-155 level was upregulated whereas MafB was downregulated in the plasma of patients with CIRI, OGD/R-induced SH-SY5Y cells, also as mouse models with MCAO injury. Mechanistically, miR-155 directly targeted 3'UTR of MafB and restrained MafB expression in OGD/R injury SH-SY5Y cells. Downregulation of miR-155 attenuated OGD/R-induced injury through increasing proliferation, inhibiting apoptosis, enhancing invasion and migration abilities, and constraining the expression of inflammatory mediators (IL-1, IL-6, and TNF-) and inflammatory enzymes (iNOS and COX-2) in SH-SY5Y cells following OGD/R, while MafB inhibition reversed the protective effects. , downregulating miR-155 reduced the infarction volume in the MACO mouse brain. Furthermore, miR-155 knockdown inhibited the IL-1, IL-6, and TNF-) and inflammatory enzymes (iNOS and COX-2) in SH-SY5Y cells following OGD/R, while MafB inhibition reversed the protective effects.
CONCLUSION
Our results suggest that miR-155 knockdown alleviated ischemia-reperfusion injury by targeting MafB to improve the neurological function and inhibit inflammation response, highlighting a novel therapeutic strategist for CIRI.
背景
研究表明，miRNA 的可变表达水平会影响缺血性中风中的炎症过程。然而，miR-155 在脑缺血再灌注损伤（CIRI）中的作用和潜在机制仍不完全清楚。
方法
通过 qRT-PCR、western blot 或免疫组化检测 CIRI 患者、氧葡萄糖剥夺/复氧（OGD/R）诱导的 SH-SY5Y 细胞和大脑中动脉闭塞（MCAO）模型小鼠血浆中的 miR-155 和 MafB 水平。通过双荧光素酶报告基因和 western blot 验证 miR-155 和 MafB 之间的关联。通过 MTT、流式细胞术、Transwell 和划痕愈合实验评估细胞活力、凋亡、侵袭和迁移。通过 TTC 测定 MCAO 小鼠脑梗死体积。通过 ELISA 测定细胞和脑组织中炎症介质的表达。
结果
CIRI 患者、OGD/R 诱导的 SH-SY5Y 细胞和 MCAO 损伤模型小鼠血浆中 miR-155 水平上调，而 MafB 水平下调。机制上，miR-155 直接靶向 MafB 的 3'UTR，抑制 OGD/R 损伤 SH-SY5Y 细胞中的 MafB 表达。下调 miR-155 通过增加增殖、抑制凋亡、增强侵袭和迁移能力以及抑制 OGD/R 后 SH-SY5Y 细胞中炎症介质（IL-1、IL-6 和 TNF-α）和炎症酶（iNOS 和 COX-2）的表达，减轻 OGD/R 诱导的损伤，而 MafB 抑制则逆转了这种保护作用。下调 miR-155 降低了 MACO 小鼠脑梗死体积。此外，miR-155 敲低抑制了 OGD/R 后 SH-SY5Y 细胞中的 IL-1、IL-6 和 TNF-α）和炎症酶（iNOS 和 COX-2），而 MafB 抑制则逆转了这种保护作用。
结论
我们的研究结果表明，通过靶向 MafB 下调 miR-155 减轻了缺血再灌注损伤，改善了神经功能，抑制了炎症反应，为 CIRI 提供了一种新的治疗策略。
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