Department of Pharmacology and Toxicology, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran.
Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
J Cell Biochem. 2018 Nov;119(10):8084-8094. doi: 10.1002/jcb.26735. Epub 2018 Jun 26.
Silibin, a flavonoid from the seeds of Silybum marianum (L.) Gaertn. (Asteraceae) has been reported to produce curative properties in diabetes. Autophagy is generated by a vast array of insults for removal of damaged proteins and organelles from the cell. Inadequate autophagy promotes endothelial cells dysfunction and delays in diabetic ulcers recovery. We hypothesized that silibinin could protect endothelial cells against high glucose-induced damage by engaging autophagic responses. HUVECs viability was evaluated by MTT assay. The Griess method and TBARS assay were used to monitor changes in the levels of nitric oxide and malondialdehyde, respectively. ROS generation was recorded in DCFDA-stained cells analyzed by flow cytometry. To investigate the role of silibinin on migration, we used scratch test. The level of autophagy proteins LC3, Becline-1, and P62 were measured by Western blotting. Our data showed that silibinin had potential to increase cell survival after exposure to high glucose condition. Total levels of oxidative stress markers were profoundly reduced and the activity of GSH was increased by silibinin. High glucose suppressed HUVECs migration to the scratched area. However, a significant increase in cell migration was observed after exposure to silibinin. Autophagy was blocked at the late stage by high glucose concentration and silibinin initiated an autophagic response by reducing P62 and enhancing Beclin-1 and LC3-II-LC3-I ratio. These effects were blocked by autophagy inhibitor of 3-Methyladenine. These observations suggest that silibinin could protect HUVECs from high glucose induced-damage possibly by activation of autophagy pathway.
水飞蓟宾，一种从水飞蓟（L.）种子中提取的类黄酮。（菊科）据报道，它对糖尿病有治疗作用。自噬是由大量的损伤蛋白和细胞器从细胞中清除而产生的。自噬不足会导致内皮细胞功能障碍，并延迟糖尿病溃疡的恢复。我们假设水飞蓟宾可以通过诱导自噬反应来保护内皮细胞免受高血糖引起的损伤。通过 MTT 测定法评估 HUVECs 的活力。使用格里斯法和 TBARS 测定法分别监测一氧化氮和丙二醛水平的变化。用 DCFDA 染色的细胞通过流式细胞术记录 ROS 的产生。为了研究水飞蓟宾对迁移的作用，我们使用划痕试验。通过 Western blot 测量自噬蛋白 LC3、Becline-1 和 P62 的水平。我们的数据表明，水飞蓟宾在暴露于高葡萄糖条件后具有增加细胞存活的潜力。总氧化应激标志物的水平显著降低，GSH 的活性增加。高葡萄糖抑制 HUVECs 向划痕区域迁移。然而，暴露于水飞蓟宾后，细胞迁移明显增加。自噬在高葡萄糖浓度下被晚期阻断，而水飞蓟宾通过降低 P62 并增强 Beclin-1 和 LC3-II-LC3-I 比值来启动自噬反应。这些作用被自噬抑制剂 3-甲基腺嘌呤阻断。这些观察结果表明，水飞蓟宾可以通过激活自噬途径来保护 HUVECs 免受高血糖引起的损伤。
