Wang Shih-Wei, Chang Chi-Chang, Hsuan Chin-Feng, Chang Tzu-Hsien, Chen Ya-Ling, Wang Yun-Ya, Yu Teng-Hung, Wu Cheng-Ching, Houng Jer-Yiing
School of Medicine, College of Medicine, I-Shou University, Kaohsiung 82445, Taiwan.
Division of Allergy, Immunology, and Rheumatology, Department of Internal Medicine, E-Da Hospital, Kaohsiung 82445, Taiwan.
Bioengineering (Basel). 2022 Oct 21;9(10):596. doi: 10.3390/bioengineering9100596.
The progression of neurodegenerative diseases is associated with oxidative stress and inflammatory responses. Abelmoschus manihot L. flower (AMf) has been shown to possess excellent antioxidant and anti-inflammatory activities. This study investigated the protective effect of ethanolic extract (AME), water extract (AMW) and supercritical extract (AMS) of AMf on PC12 neuronal cells under hydrogen peroxide (H2O2) stimulation. This study also explored the molecular mechanism underlying the protective effect of AME, which was the best among the three extracts. The experimental results showed that even at a concentration of 500 μg/mL, neither AME nor AMW showed toxic effects on PC12 cells, while AMS caused about 10% cell death. AME has the most protective effect on apoptosis of PC12 cells stimulated with 0.5 mM H2O2. This is evident by the finding when PC12 cells were treated with 500 μg/mL AME; the viability was restored from 58.7% to 80.6% in the Treatment mode (p < 0.001) and from 59.1% to 98.1% in the Prevention mode (p < 0.001). Under the stimulation of H2O2, AME significantly up-regulated the expression of antioxidant enzymes, such as catalase, glutathione peroxidase and superoxide dismutase; promoted the production of the intracellular antioxidant; reduced glutathione; and reduced ROS generation in PC12 cells. When the acute inflammation was induced under the H2O2 stimulation, AME significantly down-regulated the pro-inflammatory cytokines and mediators (e.g., TNF-α, IL-1β, IL-6, COX-2 and iNOS). AME pretreatment could also greatly promote the production of nucleotide excision repair (NER)-related proteins, which were down-regulated by H2O2. This finding indicates that AME could repair DNA damage caused by oxidative stress. Results from this study demonstrate that AME has the potential to delay the onset and progression of oxidative stress-induced neurodegenerative diseases.
神经退行性疾病的进展与氧化应激和炎症反应相关。黄蜀葵花已被证明具有出色的抗氧化和抗炎活性。本研究调查了黄蜀葵花乙醇提取物（AME）、水提取物（AMW）和超临界提取物（AMS）对过氧化氢（H2O2）刺激下PC12神经元细胞的保护作用。本研究还探讨了三种提取物中效果最佳的AME发挥保护作用的分子机制。实验结果表明，即使在浓度为500μg/mL时，AME和AMW对PC12细胞均未显示出毒性作用，而AMS导致约10%的细胞死亡。AME对0.5 mM H2O2刺激的PC12细胞凋亡具有最强的保护作用。当PC12细胞用500μg/mL AME处理时，这一点很明显；在治疗模式下，细胞活力从58.7%恢复到80.6%（p<0.001），在预防模式下从59.1%恢复到98.1%（p<0.001）。在H2O2刺激下，AME显著上调抗氧化酶如过氧化氢酶、谷胱甘肽过氧化物酶和超氧化物歧化酶的表达；促进细胞内抗氧化剂还原型谷胱甘肽的产生；并减少PC12细胞中ROS的生成。当在H2O2刺激下诱导急性炎症时，AME显著下调促炎细胞因子和介质（如TNF-α、IL-1β、IL-6、COX-2和iNOS）。AME预处理还可极大地促进核苷酸切除修复（NER）相关蛋白的产生，这些蛋白在H2O2作用下被下调。这一发现表明AME可修复氧化应激引起的DNA损伤。本研究结果表明，AME有潜力延缓氧化应激诱导的神经退行性疾病的发生和进展。
