Elderly Ward, Tongde Hospital of Zhejiang Province, Hangzhou 310012, China.
Department of Pathology, Tongde Hospital of Zhejiang Province, Hangzhou 310012, China.
Eur J Pharmacol. 2018 Aug 5;832:96-103. doi: 10.1016/j.ejphar.2018.05.029. Epub 2018 May 19.
Ischemic stroke is the leading cause of death around the world. Ginkgolide K (GK) has been used to treat ischemic stroke due to its neuroprotective potential. However, the molecular mechanism underlying the neuroprotective effect of GK in ischemic stroke is still almost blank. In this study, astrocytes were divided into four groups: control group, oxygen-glucose deprivation (OGD) group, OGD + GK group and OGD + GK + Compound C (CC) group. The viability and proliferation of astrocytes were examined by Cell Counting Kit-8 assay and 5-ethynyl-20-deoxyuridine (EdU) assay, respectively. Transwell migration and wound scratch assays were conducted to evaluate astrocyte migration. The protein expression in astrocytes were determined by western blot assay. We found that GK pretreatment promoted astrocyte proliferation and migration after OGD as shown by the increase in the viability of astrocytes, glial fibrillary acidic protein level, the number of EdU positive cells and migrated cells, and the migration distance. GK pretreatment induced autophagy after OGD, as indicated by upregulation of autophagy-related protein 7, Beclin-1 protein and increase of microtubule-associated protein 1 light chain 3 (LC3)-II/LC3-I, and downregulation of p62 protein. Moreover, GK pretreatment activated the AMP activated protein kinase (AMPK)/mammalian target of rapamycin (m-TOR)/ULK1 pathway in astrocytes following OGD. Notably, CC treatment blocked the promotory effect of GK on astrocyte proliferation and migration after OGD. Collectively, GK promoted astrocyte proliferation and migration after OGD via inducing protective autophagy through the AMPK/mTOR/ULK1 signaling pathway. Our findings suggested that GK might be a potential agent for cerebral ischemia/reperfusion injury.
缺血性脑卒中是全球范围内的主要致死原因。银杏内酯 K（GK）因其具有神经保护潜力而被用于治疗缺血性脑卒中。然而，GK 治疗缺血性脑卒中的神经保护作用的分子机制仍几乎未知。在本研究中，将星形胶质细胞分为四组：对照组、氧葡萄糖剥夺（OGD）组、OGD+GK 组和 OGD+GK+化合物 C（CC）组。通过细胞计数试剂盒-8 检测和 5-乙炔基-20-脱氧尿苷（EdU）检测分别检测星形胶质细胞的活力和增殖。通过 Transwell 迁移和划痕实验评估星形胶质细胞迁移。通过 Western blot 检测星形胶质细胞中的蛋白表达。我们发现，GK 预处理可促进 OGD 后星形胶质细胞的增殖和迁移，表现为星形胶质细胞活力增加、胶质纤维酸性蛋白水平升高、EdU 阳性细胞和迁移细胞数量增加以及迁移距离增加。OGD 后 GK 预处理诱导自噬，表现为自噬相关蛋白 7、Beclin-1 蛋白上调以及微管相关蛋白 1 轻链 3（LC3）-II/LC3-I 增加和 p62 蛋白下调。此外，OGD 后 GK 预处理激活了星形胶质细胞中的 AMP 激活的蛋白激酶（AMPK）/雷帕霉素靶蛋白（mTOR）/UNC-51 样激酶 1（ULK1）通路。值得注意的是，CC 处理阻断了 GK 对 OGD 后星形胶质细胞增殖和迁移的促进作用。总之，GK 通过诱导保护性自噬通过 AMPK/mTOR/ULK1 信号通路促进 OGD 后星形胶质细胞的增殖和迁移。我们的研究结果表明，GK 可能是脑缺血/再灌注损伤的潜在治疗药物。
