Ren Xing, Zhang Jiwei, Zhao Yunnan, Sun Lingzhi
College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, 250014, People's Republic of China.
College of Acupuncture and Massage, Shandong University of Traditional Chinese Medicine, Jinan, 250014, People's Republic of China.
Neuropsychiatr Dis Treat. 2022 Mar 4;18:513-524. doi: 10.2147/NDT.S346238. eCollection 2022.
BACKGROUND/AIM: Apoptosis and oxidative stress have been considered as key events in the pathogenesis of Alzheimer's disease (AD). Senegenin (Sen), the major and most effective ingredient of , which has anti-apoptotic and anti-oxidative effects. The aim of this study was to investigate the anti-apoptotic and anti-oxidant effects of Sen on Aβ-induced PC12 cells apoptosis and oxidative stress as well as its possible signaling pathway.
Rat pheochromocytoma (PC12) cells were treated by 20 μM Aβ and then divided into 5 different treatment groups (Control; Aβ 20 μM; Aβ 20 μM + Sen 10 μM; Aβ 20 μM + Sen 30 μM; Aβ 20μM + Sen 60 μM). PC12 cells activity was detected by MTT assay. Colony formation assay was performed to assess the clonogenic ability of cells. The cell apoptosis was detected by Annexin-V/PI staining. The pro-apoptotic protein (Bax), anti-apoptotic protein (Bcl-2), anti-oxidative stress factor (HO-1, Nuclear Nrf2, Total Nrf2) and pathway-related protein (Akt, P-Akt, PI3K, P-PI3K) were tested by Western blot. The reactive oxygen species (ROS) level was assessed with a DCFH-DA probe.
The results indicated that Sen dose-dependently increased cell viability and reduced the number of apoptotic cells. The ratio of P-PI3K/PI3K and P-Akt/Akt increased in a dose-dependent manner under the treatment of Sen, suggesting that Sen might activate the PI3K/Akt signaling pathway. Moreover, Sen upregulates the ratio of Bcl-2/Bax. Further study revealed that Sen can play an antioxidant role in enhancing HO-1, promoting Nrf2 nuclear translocation and reducing ROS accumulation to reduce oxidative stress.
Sen is effective in inhibiting apoptosis and oxidative stress in Aβ-induced PC12 cells, which likely contribute to the development of novel therapies for AD.
背景/目的：细胞凋亡和氧化应激被认为是阿尔茨海默病（AD）发病机制中的关键事件。远志皂苷元（Sen）是远志的主要且最有效的成分，具有抗凋亡和抗氧化作用。本研究旨在探讨远志皂苷元对β淀粉样蛋白（Aβ）诱导的PC12细胞凋亡和氧化应激的抗凋亡及抗氧化作用及其可能的信号通路。
用20μM Aβ处理大鼠嗜铬细胞瘤（PC12）细胞，然后分为5个不同的处理组（对照组；20μM Aβ组；20μM Aβ + 10μM远志皂苷元组；20μM Aβ + 30μM远志皂苷元组；20μM Aβ + 60μM远志皂苷元组）。采用MTT法检测PC12细胞活性。进行集落形成试验以评估细胞的克隆形成能力。通过Annexin-V/PI染色检测细胞凋亡。采用蛋白质免疫印迹法检测促凋亡蛋白（Bax）、抗凋亡蛋白（Bcl-2）、抗氧化应激因子（血红素加氧酶-1（HO-1）、细胞核因子E2相关因子2（Nuclear Nrf2）、总Nrf2）和通路相关蛋白（蛋白激酶B（Akt）、磷酸化Akt（P-Akt）、磷脂酰肌醇-3激酶（PI3K）、磷酸化PI3K（P-PI3K））。用2',7'-二氯二氢荧光素二乙酸酯（DCFH-DA）探针评估活性氧（ROS）水平。
结果表明，远志皂苷元剂量依赖性地增加细胞活力并减少凋亡细胞数量。在远志皂苷元处理下，P-PI3K/PI3K和P-Akt/Akt的比值呈剂量依赖性增加，表明远志皂苷元可能激活PI3K/Akt信号通路。此外，远志皂苷元上调Bcl-2/Bax的比值。进一步研究表明，远志皂苷元可通过增强HO-1、促进Nrf2核转位和减少ROS积累来发挥抗氧化作用，从而减轻氧化应激。
远志皂苷元可有效抑制Aβ诱导的PC12细胞凋亡和氧化应激，这可能有助于开发AD的新疗法。
