Huang Baosheng, Chen Panhong, Huang Lei, Li Shuai, Zhu Ronglan, Sheng Tao, Yu Wan, Chen Zheng, Wang Tianlu
Department of Neurosurgery, Sir Run Run Hospital, Nanjing Medical University, Nanjing, China.
Department of laboratory Medicine, First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
Cell Physiol Biochem. 2017;43(2):705-716. doi: 10.1159/000480657. Epub 2017 Sep 22.
BACKGROUND/AIMS: Calcium-permeable ionotropic NMDAR-mediated hyperactivity is regarded as the critical factor in modulating the development of ischaemic stroke. Recently, there has been increasing interest in preventing post-stroke neuronal death by focusing on intervening in the function of subpopulations of NMDARs and their downstream signalling. Geniposide, an iridoid glycoside, has been found to have cytoprotective functions in various conditions. However, it is still unclear whether and how geniposide affects neuronal insult under experimental stroke.
We demonstrate that dose-dependent geniposide significantly decreased the infarct volume in tMCAO models.
A medium level of geniposide improved anti-apoptotic functions and inhibited BBB leakage/haemorrhage via elevating GluN2A-containing NMDAR expression in tMCAO rats. Importantly, these effects could be eliminated by co-treatment of geniposide with the GluN2A antagonist NVP but not the GluN2B inhibitor ifenprodil. Moreover, geniposide's protection was due to the enhancement of GluN2A-dependent survival signals, including pAKT, pERK and PSD-95.
The results suggest that geniposide protects neurons against post-ischaemic neurovascular injury through the activation of GluN2A/AKT/ERK pathways. As a very promising natural agent, geniposide may be a future therapeutic for stroke patients.
背景/目的:钙通透性离子型NMDAR介导的功能亢进被认为是调节缺血性脑卒中发展的关键因素。近来,通过关注干预NMDAR亚群的功能及其下游信号传导来预防脑卒中后神经元死亡受到越来越多的关注。栀子苷,一种环烯醚萜苷,已被发现在多种情况下具有细胞保护功能。然而,栀子苷是否以及如何影响实验性脑卒中时的神经元损伤仍不清楚。
我们证明剂量依赖性的栀子苷显著降低了tMCAO模型中的梗死体积。
中等剂量的栀子苷通过提高tMCAO大鼠中含GluN2A的NMDAR表达改善了抗凋亡功能并抑制了血脑屏障渗漏/出血。重要的是,栀子苷与GluN2A拮抗剂NVP共同处理可消除这些作用,但与GluN2B抑制剂艾芬地尔共同处理则不能。此外,栀子苷的保护作用归因于GluN2A依赖性存活信号的增强,包括pAKT、pERK和PSD-95。
结果表明栀子苷通过激活GluN2A/AKT/ERK途径保护神经元免受缺血后神经血管损伤。作为一种非常有前景的天然药物,栀子苷可能成为未来脑卒中患者的治疗药物。