Objective: To explore the mechanism by which LncRNA SNHG8 regulates miR-494-3p expression to alleviate cerebral ischemia-reperfusion injury.
Methods: A mouse model of cerebral ischemia-reperfusion injury was established, and TTC staining was used to determine the infarct area; ELISA was used to detect the contents of the inflammatory factors IL-1β, IL-6 and TNF-α in the brain tissue, and RT-qPCR was performed to detect the expression levels of LncRNA MALAT1 and miR-155-5p. A microglial cell model overexpressing LncRNA SNHG8 was exposed to oxygen-glucose deprivation/reoxygenation (OGD/R), and inflammatory reaction and apoptosis of the cells were detected using ELISA and flow cytometry. A luciferase reporter assay was used to detect the targeting relationship between LncRNA SNHG8 and miR-494-3p. We further constructed a microglial cell model overexpressing both LncRNA SNHG8 the miR-494-3p, and examined inflammatory reactions and apoptosis of the cells following OGD/R exposure.
Results: In the mouse model of cerebral ischemia-reperfusion injury, the contents of inflammatory factors IL-1β, IL-6 and TNF-α increased significantly in the brain tissue (P < 0.001), where LncRNA SNHG8 expression was lowered (P < 0.01) and miR-494-3p expression increased significantly (P < 0.01). In the microglial cells, overexpression of LncRNA SNHG8 significantly inhibited the inflammatory reaction and apoptosis following OGD/R exposure (P < 0.01), and overexpression of LncRNA SNHG8 strongly inhibited the expression of miR-494-3p (P < 0.01). Overexpression of miR-494-3p in microglia overexpressing SNHG8 partially promoted inflammatory reaction and cell apoptosis in response to OGD/R (P < 0.05).
Conclusion: LncRNA SNHG8 can improve cerebral ischemia-reperfusion injury in mice by inhibiting the expression of miR-494-3p and suppressing inflammatory reactions and apoptosis of the microglia.
目的: 探究LncRNA SNHG8调控miR-494-3p表达减轻脑缺血再灌注损伤的发生机制。
方法: 构建小鼠脑缺血再灌注损伤模型，通过TTC染色检测梗死面积，ELISA检测脑组织中炎症因子IL-1β、IL-6和TNF-α含量，RT-qPCR检测脑组织中LncRNA SNHG8和miR-494-3p的表达。构建过表达LncRNA SNHG8的OGD/R模型小胶质细胞，细胞分为OGD/R+oe-NC组或OGD/R+oe-SNHG8组，并通过ELISA和流式细胞术检测细胞的炎症反应和凋亡情况。双荧光素酶实验验证LncRNA SNHG8和miR-494-3p的靶向关系。在oe-SNHG8的OGD/R模型小胶质细胞中进一步过表达miR-494-3p，细胞分为OGD/R+oe-SNHG8+mimic NC组或OGD/R+oe-SNHG8+miR-494-3p mimic组，检测细胞炎症反应和凋亡的变化。
结果: 小鼠脑缺血再灌注损伤模型中，脑组织出现明显的梗死区，炎症因子IL-1β、IL-6和TNF-α的含量明显增加（P < 0.001），lncRNA SNHG8低表达（P < 0.01），而miR-494-3p高表达（P < 0.01）。过表达LncRNA SNHG8明显抑制OGD/R模型小胶质细胞的炎症反应和凋亡（P < 0.01）。过表达LncRNA SNHG8能抑制miR-494-3p的表达（P < 0.01）。在oe-SNHG8的OGD/R模型小胶质细胞中进一步过表达miR-494-3p，部分促进细胞的炎症反应和凋亡（P < 0.05）。
结论: LncRNA SNHG8通过抑制miR-494-3p表达，抑制炎症反应和细胞凋亡，从而改善脑缺血再灌注损伤。
Keywords: LncRNA SNHG8; apoptosis; cerebral ischemia-reperfusion injury; inflammatory reaction; miR-494-3p.