State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China.
Invest Ophthalmol Vis Sci. 2024 Feb 1;65(2):18. doi: 10.1167/iovs.65.2.18.
TGF-β/BMP signaling pathway plays a significant role in fibrotic cataract. Smurf1, a ubiquitin protein ligase, regulates the TGF-β/BMP signaling pathway through the ubiquitin-proteasome system (UPS). This study aims to investigate the role of Smurf1 in the progression of fibrotic cataract and its underlying mechanism.
We used a mouse model of injury-induced anterior subcapsular cataract (ASC) and administered the Smurf1 inhibitor A01 for in vivo investigations. RNA sequencing was performed to examine global gene expression changes. Protein levels were assessed by Simple Western analysis. The volume of subcapsular opacity was determined using whole-mount immunofluorescence of lens anterior capsules. Lentivirus was utilized to establish cell lines with Smurf1 knockdown or overexpression in SRA01/04. Lens epithelial cell (LEC) proliferation was evaluated by CCK8 and EdU assays. Cell cycle profile was determined by flow cytometry. LEC migration was measured using Transwell and wound healing assays.
The mRNA levels of genes associated with cell proliferation, migration, epithelial-mesenchymal transition (EMT), TGF-β/BMP pathway, and UPS were upregulated in mouse ASC model. Smurf1 mRNA and protein levels were upregulated in lens capsules of patients and mice with ASC. Anterior chamber injection of A01 inhibited ASC formation and EMT. In vitro, Smurf1 knockdown reduced proliferation, migration and TGF-β2-induced EMT of LECs, concomitant with the upregulation of Smad1, Smad5, and pSmad1/5. Conversely, overexpression of Smurf1 showed opposite phenotypes.
Smurf1 regulates fibrotic cataract progression by influencing LEC proliferation, migration, and EMT through the modulation of the Smad signaling pathway, offering a novel target for the fibrotic cataract treatment.
TGF-β/BMP 信号通路在纤维性白内障中起着重要作用。Smurf1 是一种泛素蛋白连接酶，通过泛素蛋白酶体系统 (UPS) 调节 TGF-β/BMP 信号通路。本研究旨在探讨 Smurf1 在纤维性白内障进展中的作用及其潜在机制。
我们使用损伤诱导的前囊下白内障 (ASC) 小鼠模型进行体内研究，并给予 Smurf1 抑制剂 A01。采用 RNA 测序检测全局基因表达变化。通过 Simple Western 分析评估蛋白水平。采用晶状体前囊的全囊免疫荧光检测评估前囊下混浊的体积。利用慢病毒建立 Smurf1 敲低或过表达的 SRA01/04 细胞系。通过 CCK8 和 EdU 检测评估晶状体上皮细胞 (LEC) 增殖。通过流式细胞术测定细胞周期谱。通过 Transwell 和划痕愈合实验测量 LEC 迁移。
与细胞增殖、迁移、上皮-间充质转化 (EMT)、TGF-β/BMP 通路和 UPS 相关的基因在小鼠 ASC 模型中的 mRNA 水平上调。Smurf1 mRNA 和蛋白水平在 ASC 患者和小鼠的晶状体囊内上调。前房注射 A01 抑制 ASC 形成和 EMT。体外，Smurf1 敲低减少了 LEC 的增殖、迁移和 TGF-β2 诱导的 EMT，同时上调了 Smad1、Smad5 和 pSmad1/5。相反，Smurf1 的过表达表现出相反的表型。
Smurf1 通过调节 Smad 信号通路影响 LEC 的增殖、迁移和 EMT，从而调节纤维性白内障的进展，为纤维性白内障的治疗提供了一个新的靶点。
