Xia Cong, Deng Yan, Lu Yichen, Kang Lumei, Wan Xiaojuan, Chen Hongping, Yin Xiaolong
Department of Ophthalmology, the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, 330006, PR China; Department of Pathology, Ganzhou Hospital of Guangdong Provincial People's Hospital, Ganzhou Municipal Hospital, Ganzhou, 341000, Jiangxi Province, PR China.
Department of Ophthalmology, the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, 330006, PR China.
Exp Eye Res. 2025 Sep;258:110486. doi: 10.1016/j.exer.2025.110486. Epub 2025 Jun 15.
Toll-like receptor 4 (TLR4), recognized as a fundamental mediator of inflammatory signaling, plays a crucial role in orchestrating the inflammatory response. Previous studies suggested that TLR4 knockout (KO) notably reduced corneal vascular areas induced by silver nitrate burn based on the morphological observation. The current study seeks to elucidate the influence of TLR4 signaling on corneal neovascularization (CNV) and to examine the underlying mechanisms. The model of alkali burn (AB)-induced CNV was built using TLR4 KO and wildtype (WT) mice. CNV was detected using a slit lamp. Corneal thickness was evaluated using H&E staining. The expression levels of VEGF-A, MyD88, and NF-κB were evaluated employing Western blot analysis, immunohistochemistry, and Real-time PCR techniques. The inflammation factors, IL-1β, TNF-α, and IL-6, were quantified using Real-time PCR. In addition, Resatorvid (Tak242), a specific inhibitor of TLR4, was used to treat AB cornea of WT mice. AB enhanced TLR4 signaling components, including MyD88 and NF-κB. TLR4 inhibition alleviated AB-induced corneal neovascularization and corneal thickness. The TLR4 signal, inflammatory factors and VEGF-A were also down-regulated. Our data indicated that TLR4 participated in the pathology of AB-induced CNV. TLR4 was over-expressed in the cornea of AB mice. TLR4 inhibition alleviated AB-induced CNV, and suppressed MyD88, NF-κB, VEGF-A, and inflammation factors. These findings may provide new insights for the clinical treatment of AB-induced CNV.
Toll样受体4（TLR4）被认为是炎症信号传导的基本介质，在协调炎症反应中起关键作用。先前的研究表明，基于形态学观察，TLR4基因敲除（KO）显著减少了硝酸银烧伤诱导的角膜血管面积。本研究旨在阐明TLR4信号传导对角膜新生血管形成（CNV）的影响，并探讨其潜在机制。使用TLR4基因敲除小鼠和野生型（WT）小鼠建立碱烧伤（AB）诱导的CNV模型。使用裂隙灯检测CNV。使用苏木精和伊红（H&E）染色评估角膜厚度。采用蛋白质免疫印迹分析、免疫组织化学和实时定量聚合酶链反应（Real-time PCR）技术评估血管内皮生长因子A（VEGF-A）、髓样分化因子88（MyD88）和核因子κB（NF-κB）的表达水平。使用实时定量聚合酶链反应对炎症因子白细胞介素-1β（IL-1β）、肿瘤坏死因子-α（TNF-α）和白细胞介素-6（IL-6）进行定量分析。此外，使用TLR4的特异性抑制剂雷沙托维德（Tak242）治疗野生型小鼠的AB角膜。AB增强了包括MyD88和NF-κB在内的TLR4信号传导成分。TLR4抑制减轻了AB诱导的角膜新生血管形成和角膜厚度。TLR4信号、炎症因子和VEGF-A也下调。我们的数据表明，TLR4参与了AB诱导的CNV的病理过程。TLR4在AB小鼠的角膜中过度表达。TLR4抑制减轻了AB诱导的CNV，并抑制了MyD8&、NF-κB、VEGF-A和炎症因子。这些发现可能为AB诱导的CNV的临床治疗提供新的见解。
