Feng Yuelai, Jiang Chang, Yang Feng, Chen Zixian, Li Zheng
Department of International Baccalaureate Diploma Program, Shanghai Pinghe School, Shanghai 200127, P.R. China.
Department of Orthopaedics, Zhongshan Hospital of Fudan University, Shanghai 200032, P.R. China.
Biomed Rep. 2020 Aug;13(2):6. doi: 10.3892/br.2020.1313. Epub 2020 Jun 9.
The effect of leaf extract (AVLE) on the nervous system has been widely studied, but its effect on injured neurons is not fully understood. In the present study, the protective effect of AVLE on injured neurons was determined. HO was used to induce oxidative stress in PC12 cells and cell viability assays were used to determine the optimum concentration range of AVLE and its protective effects against oxidative stress. A live-dead assay was performed to confirm the effects of AVLE on oxidative stress. Subsequently, expression of apoptotic proteins including Bax and cleaved-caspase-3 were evaluated to determine whether AVLE affected apoptosis, and reactive oxygen species (ROS) levels were detected to determine the role of AVLE in HO exposure. Furthermore, expression of autophagic proteins including LC3-II and p62 were detected to evaluate the effects of AVLE on autophagic activity, and cells were treated with 3-methyladenine (3-MA), an autophagic inhibitor, to identify the underlying protective mechanism of AVLE. The results showed that the optimum conditions to induce oxidative stress were treatment with 40 µM HO for 2 h, and the suitable range of AVLE concentrations was shown to be 1-100 µg/ml. AVLE improved cell viability in PC12 cells following treatment with HO. AVLE reduced the expression of Bax and cleaved-caspase-3, and decreased ROS production. Furthermore, AVLE upregulated LC3-II expression and downregulated p62 expression, whereas treatment with 3-MA increased the levels of ROS and apoptotic proteins. These results suggest that AVLE may protect injured neurons against oxidative stress-induced apoptosis, and this effect may be associated with the reduction of ROS by increasing autophagy.
叶提取物（AVLE）对神经系统的作用已得到广泛研究，但其对受损神经元的作用尚未完全明确。在本研究中，确定了AVLE对受损神经元的保护作用。使用HO诱导PC12细胞发生氧化应激，并通过细胞活力测定来确定AVLE的最佳浓度范围及其对氧化应激的保护作用。进行活死细胞检测以确认AVLE对氧化应激的影响。随后，评估包括Bax和裂解的caspase-3在内的凋亡蛋白的表达，以确定AVLE是否影响细胞凋亡，并检测活性氧（ROS）水平以确定AVLE在HO处理中的作用。此外，检测包括LC3-II和p62在内的自噬蛋白的表达，以评估AVLE对自噬活性的影响，并用自噬抑制剂3-甲基腺嘌呤（3-MA）处理细胞，以确定AVLE潜在的保护机制。结果表明，诱导氧化应激的最佳条件是用40μM HO处理2小时，AVLE的合适浓度范围为1-100μg/ml。HO处理后，AVLE提高了PC12细胞的活力。AVLE降低了Bax和裂解的caspase-3的表达，并减少了ROS的产生。此外，AVLE上调了LC3-II的表达，下调了p62的表达，而用3-MA处理则增加了ROS和凋亡蛋白的水平。这些结果表明，AVLE可能保护受损神经元免受氧化应激诱导的细胞凋亡，并且这种作用可能与通过增加自噬来减少ROS有关。
