Department of Bioengineering, College of Biological Science and Biotechnology, Fuzhou University, Fuzhou 350104, China.
Department of Ophthalmology, Affiliated People's Hospital (Fujian Provincial People's Hospital), Fujian University of Traditional Chinese Medicine, Fuzhou 350004, China.
J Tradit Chin Med. 2024 Apr;44(2):268-276. doi: 10.19852/j.cnki.jtcm.20240203.005.
To investigate the effects of emodin on alkali burn-induced corneal inflammation and neovascularization.
The ability of emodin to target vascular endothelial growth factor receptor 2 (VEGFR2) was predicted by molecular docking. The effects of emodin on the invasion, migration, and proliferation of human umbilical vein endothelial cells (HUVEC) were determined by cell counting kit-8, Transwell, and tube formation assays. Analysis of apoptosis was performed by flow cytometry. CD31 levels were examined by immunofluorescence. The abundance and phosphorylation state of VEGFR2, protein kinase B (Akt), signal transducer and activator of transcription 3 (STAT3), and P38 were examined by immunoblot analysis. Corneal alkali burn was performed on 40 mice. Animals were divided randomly into two groups, and the alkali-burned eyes were then treated with drops of either 10 μM emodin or phosphate buffered saline (PBS) four times a day. Slit-lamp microscopy was used to evaluate inflammation and corneal neovascularization (CNV) in all eyes on Days 0, 7, 10, and 14. The mice were killed humanely 14 d after the alkali burn, and their corneas were removed and preserved at －80 ℃ until histological study or protein extraction.
Molecular docking confirmed that emodin was able to target VEGFR2. The findings revealed that emodin decreased the invasion, migration, angiogenesis, and proliferation of HUVEC in a dose-dependent manner. In mice, emodin suppressed corneal inflammatory cell infiltration and inhibited the development of corneal neovascularization induced by alkali burn. Compared to those of the PBS-treated group, lower VEGFR2 expression and CD31 levels were found in the emodin-treated group. Emodin dramatically decreased the expression of VEGFR2, p-VEGFR2, p-Akt, p-STAT3, and p-P38 in VEGF-treated HUVEC.
This study provides a new avenue for evaluating the molecular mechanisms underlying corneal inflammation and neovascularization. Emodin might be a promising new therapeutic option for corneal alkali burns.
研究大黄素对碱烧伤诱导的角膜炎症和新生血管形成的影响。
通过分子对接预测大黄素对血管内皮生长因子受体 2（VEGFR2）的靶向作用。通过细胞计数试剂盒-8、Transwell 和管形成测定法测定大黄素对人脐静脉内皮细胞（HUVEC）侵袭、迁移和增殖的影响。通过流式细胞术分析细胞凋亡。通过免疫荧光法检测 CD31 水平。通过免疫印迹分析检测 VEGFR2、蛋白激酶 B（Akt）、信号转导和转录激活因子 3（STAT3）和 P38 的丰度和磷酸化状态。对 40 只小鼠进行角膜碱烧伤。动物随机分为两组，然后每天用 10 μM 大黄素或磷酸盐缓冲盐水（PBS）滴眼 4 次治疗碱烧伤眼。在第 0、7、10 和 14 天，所有眼睛均通过裂隙灯显微镜评估炎症和角膜新生血管化（CNV）。碱烧伤后 14 天，将小鼠安乐死，取出角膜并在-80℃保存，直至进行组织学研究或蛋白质提取。
分子对接证实大黄素能够靶向 VEGFR2。研究结果表明，大黄素以剂量依赖的方式降低 HUVEC 的侵袭、迁移、血管生成和增殖。在小鼠中，大黄素抑制角膜炎性细胞浸润并抑制碱烧伤诱导的角膜新生血管形成。与 PBS 处理组相比，大黄素处理组的角膜中 VEGFR2 表达和 CD31 水平较低。大黄素显著降低了 VEGF 处理的 HUVEC 中 VEGFR2、p-VEGFR2、p-Akt、p-STAT3 和 p-P38 的表达。
本研究为评估角膜炎症和新生血管形成的分子机制提供了新的途径。大黄素可能是治疗角膜碱烧伤的一种有前途的新治疗选择。
