Department of Biomedical and Biotechnological Sciences, School of Medicine, Section of Medical Biochemistry, University of Catania, 95123 Catania, Sicilia, Italy.
Faculty of Medicine and Surgery, University of Enna "Kore'', 94100 Enna, Sicilia, Italy.
Front Biosci (Landmark Ed). 2022 Nov 17;27(11):308. doi: 10.31083/j.fbl2711308.
Reactive oxygen species (ROS) accumulation plays a pivotal role in the onset of cell damage induced by hyperglycemia and represents one of the major factors in the pathogenesis of diabetic retinopathy. In this study, we tested the antioxidants cyanidin-3-O-glucoside (C3G) and verbascoside (Verb) in the protection of retinal endothelium against glucose toxicity "".
Increasing amounts (5-50 μM) of C3G, Verb or the combination of both compounds were tested in Human Retinal Endothelial Cells (HREC) grown with normal glucose (5 mM, NG) or high glucose (25 mM, HG).
Reduced cell viability and enhanced ROS levels (evaluated by MTT and H2DCFDA assays, respectively) in HG-stimulated HREC were restored by C3G and Verb in a dose-dependent manner, achieving the maximum protection in the presence of both compounds. Moreover, co-treatment with C3G and Verb worked better than each single molecule alone in the prevention of the disruption of blood-retinal-barrier-like properties by HG in a confluent HREC monolayer, as assessed by trans endothelial electrical resistance (TEER) and Na-Fluorescein permeability assays. Accordingly, C3G and Verb together also better counteracted the HG-induced down-regulation of the tight junction membrane proteins Zonula Occludens-1 and VE-Cadherin evaluated by immunocytochemical and Western blot analyses.
In conclusion, our data indicate that C3G and Verb could efficiently protect the retinal endothelium against high glucose damage.
活性氧（ROS）的积累在高血糖诱导的细胞损伤的发生中起着关键作用，是糖尿病性视网膜病变发病机制中的主要因素之一。在这项研究中，我们测试了抗氧化剂矢车菊素-3-O-葡萄糖苷（C3G）和毛蕊花糖苷（Verb）对视网膜内皮细胞抵抗葡萄糖毒性的保护作用。
用正常葡萄糖（5 mM，NG）或高葡萄糖（25 mM，HG）培养人视网膜内皮细胞（HREC），检测 C3G、Verb 或两者联合应用于不同浓度（5-50 μM）时的效果。
HG 刺激的 HREC 中细胞活力降低和 ROS 水平升高（分别通过 MTT 和 H2DCFDA 测定评估），用 C3G 和 Verb 以剂量依赖性方式恢复，在两种化合物存在时达到最大保护作用。此外，C3G 和 Verb 联合处理比单独使用每种分子在预防高糖引起的人视网膜内皮细胞单层中血视网膜屏障样特性破坏方面效果更好，如跨内皮电阻（TEER）和 Na-荧光素通透性测定所示。因此，C3G 和 Verb 一起也更好地对抗了 HG 诱导的紧密连接膜蛋白 Zonula Occludens-1 和 VE-Cadherin 的下调，这通过免疫细胞化学和 Western blot 分析进行评估。
总之，我们的数据表明 C3G 和 Verb 可以有效地保护视网膜内皮细胞免受高葡萄糖损伤。
