Department of Neurology, Guangdong Provincial Hospital of Chinese Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Postdoctoral Research Station of Guangdong Provincial Hospital of Chinese Medicine, Guangzhou 510120, PR China.
Department of Neurology, Guangdong Provincial Hospital of Chinese Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Postdoctoral Research Station of Guangdong Provincial Hospital of Chinese Medicine, Guangzhou 510120, PR China; The First Clinical Medical College of Guangzhou University of Chinese Medicine, Guangzhou 510405, PR China.
Brain Res Bull. 2021 Aug;173:124-131. doi: 10.1016/j.brainresbull.2021.05.002. Epub 2021 May 8.
Ischaemic stroke is attributable to cerebrovascular disease and is associated with high morbidity, disability, mortality and recurrence. Autophagy is a critical mediator and plays dual roles in ischaemic stroke. Autophagy can protect against ischaemic brain injury during the early stage of ischaemic stroke, while excessive autophagy can induce apoptosis and exacerbate brain injury. However, the time-dependent variations in autophagy in ischaemic stroke are unknown. C57BL/6 mice were used to establish a model of temporary middle cerebral artery occlusion and reperfusion (tMCAO). The neurological functional scores and infarct volumes were determined at 1 d, 3 d, 5 d, and 7 d after modelling. The levels of Beclin-1, LC3B, p62, GFAP, TNF-α, IL-6, IL-10, ROS, 4-HNE and 8-OHDG were measured by ELISA, RT-PCR, immunofluorescence analysis and western blotting. The morphology of autophagosomes of ischaemic penumbra was observed by transmission electron microscopy (TEM). Beclin-1, LC3B, ROS, 4-HNE, 8-OHDG, GFAP, TNF-α and IL-6 levels increased (P < 0.01), while p62 and IL-10 levels decreased (P < 0.01) after tMCAO compared to those in the sham group. Beclin-1, LC3B, ROS, 4-HNE, 8-OHDG, GFAP, TNF-α and IL-6 levels were reduced in tMCAO mice at 3 d, 5 d and 7 d (P<0.05), and p62 and IL-10 levels were enhanced (P < 0.05) compared to those at 1 d. In addition, Beclin-1 positively correlated with LC3B, GFAP, TNF-α, IL-6, ROS, 4-HNE and 8-OHDG (P < 0.05), and Beclin-1 negatively correlated with p62 and IL-10 (P < 0.05). The number of autophagosomes was consistent with the expression of autophagy marker proteins, both showing a steady decrease. In summary, autophagy was activated within 7 d of tMCAO induction, and it strengthened at 1 d and then weakened steadily from 3 to 7 d. In addition, this study verified that autophagy positively correlated with the inflammatory response and oxidative stress at 7 d after tMCAO.
缺血性中风归因于脑血管疾病，与高发病率、残疾、死亡率和复发率有关。自噬是一种关键的调节剂，在缺血性中风中发挥双重作用。自噬可以在缺血性中风的早期阶段保护缺血性脑损伤，而过度的自噬会诱导细胞凋亡并加重脑损伤。然而，缺血性中风中自噬的时间依赖性变化尚不清楚。使用 C57BL/6 小鼠建立短暂性大脑中动脉闭塞和再灌注（tMCAO）模型。在建模后 1d、3d、5d 和 7d 时测定神经功能评分和梗死体积。通过 ELISA、RT-PCR、免疫荧光分析和 Western blot 测定 Beclin-1、LC3B、p62、GFAP、TNF-α、IL-6、IL-10、ROS、4-HNE 和 8-OHDG 的水平。通过透射电子显微镜（TEM）观察缺血半影区自噬体的形态。与假手术组相比，tMCAO 后 Beclin-1、LC3B、ROS、4-HNE、8-OHDG、GFAP、TNF-α和 IL-6 水平升高（P<0.01），而 p62 和 IL-10 水平降低（P<0.01）。tMCAO 后 3d、5d 和 7d，tMCAO 小鼠的 Beclin-1、LC3B、ROS、4-HNE、8-OHDG、GFAP、TNF-α和 IL-6 水平降低（P<0.05），p62 和 IL-10 水平升高（P<0.05）。此外，Beclin-1 与 LC3B、GFAP、TNF-α、IL-6、ROS、4-HNE 和 8-OHDG 呈正相关（P<0.05），与 p62 和 IL-10 呈负相关（P<0.05）。自噬体的数量与自噬标志物蛋白的表达一致，均呈持续下降趋势。总之，tMCAO 诱导后 7d 内自噬被激活，在 1d 时增强，然后从 3d 到 7d 稳定减弱。此外，本研究验证了自噬在 tMCAO 后 7d 与炎症反应和氧化应激呈正相关。
