Zhong Yu, Qi Ao, Liu Lulu, Huang Qionglin, Zhang Junjie, Cai Kangrong, Cai Chun
Southern Marine Science and Engineering Guangdong Laboratory, Zhanjiang, Guangdong 524023, P.R. China.
Analysis Center, Guangdong Medical University, Zhanjiang, Guangdong 524023, P.R. China.
Exp Ther Med. 2021 Oct;22(4):1118. doi: 10.3892/etm.2021.10552. Epub 2021 Aug 4.
Shikonin, a natural naphthoquinone extracted from the roots of , possesses multiple pharmacological properties, including antioxidant, anti-inflammatory and antitumor effects. It has been hypothesized that the properties of shikonin are associated with its oxygen free radical scavenging abilities. However, the mechanism underlying the antioxidant activity of shikonin is not completely understood. The aim of the present study was to investigate the effect of shikonin against HO-induced oxidative injury in HT29 cells and to explore the underlying molecular mechanism. The concentration and duration of HO treatment to cause maximal damage, and the effects of shikonin (2.5, 5 or 10 µg/ml) on the activity of HO-induced HT29 cells were determined by MTT assay. The apoptotic rate in HT29 cells was determined by annexin V/propidium iodide staining. HT29 cell cycle alteration was also analyzed by propidium iodide staining. Reactive oxygen species (ROS) production was assessed by monitoring 2',7'-dichlorofluorescin in diacetate fluorescence. Mitochondrial membrane potentials were determined by JC-1 staining. The activities of malondialdehyde, superoxide dismutase, caspase-9 and caspase-3 were measured using spectrophotometric assays. The expression levels of Bcl-2, Bax and cytochrome were determined by western blotting. The results suggested that shikonin increased cell viability, reduced cell apoptosis and increased the proliferation index in HO-treated HT29 cells. Shikonin also significantly inhibited increases in intracellular reactive oxygen species (ROS), restored the mitochondrial membrane potential, prevented the release of lactic dehydrogenase and decreased the levels of superoxide dismutase and malondialdehyde in HO-induced HT29 cells. Furthermore, shikonin significantly decreased caspase-9 and caspase-3 activities, increased Bcl-2 expression and decreased Bax and cytochrome expression levels in HO-induced HT29 cells. The results indicated that shikonin protected against HO-induced oxidative injury by removing ROS, ameliorating mitochondrial dysfunction, attenuating DNA oxidative damage and inhibiting mitochondrial pathway-mediated apoptosis.
紫草素是从紫草根部提取的一种天然萘醌，具有多种药理特性，包括抗氧化、抗炎和抗肿瘤作用。据推测，紫草素的这些特性与其清除氧自由基的能力有关。然而，紫草素抗氧化活性的潜在机制尚未完全明确。本研究旨在探讨紫草素对过氧化氢（HO）诱导的HT29细胞氧化损伤的影响，并探究其潜在的分子机制。通过MTT法测定引起最大损伤的HO处理浓度和持续时间，以及紫草素（2.5、5或10μg/ml）对HO诱导的HT29细胞活性的影响。采用膜联蛋白V/碘化丙啶染色法测定HT29细胞的凋亡率。还用碘化丙啶染色分析HT29细胞周期变化。通过监测二乙酸荧光素二氯荧光素评估活性氧（ROS）的产生。采用JC-1染色法测定线粒体膜电位。使用分光光度法测定丙二醛、超氧化物歧化酶、半胱天冬酶-9和半胱天冬酶-3的活性。通过蛋白质免疫印迹法测定Bcl-2、Bax和细胞色素的表达水平。结果表明，紫草素可提高HO处理的HT29细胞的活力，降低细胞凋亡并增加增殖指数。紫草素还能显著抑制HO诱导的HT29细胞内活性氧（ROS）的增加，恢复线粒体膜电位，阻止乳酸脱氢酶的释放，并降低超氧化物歧化酶和丙二醛的水平。此外，紫草素可显著降低HO诱导的HT29细胞中半胱天冬酶-9和半胱天冬酶-3的活性，增加Bcl-2的表达，并降低Bax和细胞色素的表达水平。结果表明，紫草素通过清除ROS、改善线粒体功能障碍、减轻DNA氧化损伤和抑制线粒体途径介导的凋亡来保护细胞免受HO诱导的氧化损伤。
