Department of Cardiovascular Medicine, Lishui People's Hospital, Lishui, Zhejiang, China.
Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China.
Cardiovasc Toxicol. 2024 Nov;24(11):1253-1267. doi: 10.1007/s12012-024-09911-z. Epub 2024 Aug 24.
Circular RNAs (circRNAs) play an important role in the progression of atherosclerosis (AS). This study aimed to explore the exact role and mechanism of circ_0002984 in oxidized low-density lipoprotein (ox-LDL)-mediated human vascular smooth muscle cells (HVSMCs). The model of smooth muscle cell phenotype switching was constructed by treating HVSMCs with ox-LDL. The levels of circ_0002984, let-7a-5p, and kruppel-like factor 5 (KLF5) were measured by quantitative real-time PCR or western blot assay. Cell proliferation, migration, and apoptosis were detected by Cell Counting Kit-8 (CCK-8), EdU staining, wound healing assay, transwell assay, and flow cytometry. The expression of cleaved-caspase-3 and KLF5 was examined by western blot. The relationship between let-7a-5p and circ_0002984 or KLF5 was verified by dual-luciferase reporter assay or RIP assay. The results showed that circ_0002984 and KLF5 were up-regulated, while let-7a-5p was down-regulated in AS patients and ox-LDL-disposed HVSMCs. Silence of circ_0002984 suppressed proliferation and migration, and promoted apoptosis in ox-LDL-stimulated HVSMCs. Moreover, circ_0002984 sponged let-7a-5p to regulate the proliferation, migration, and apoptosis in ox-LDL-resulted HVSMCs. In addition, KLF5 was a target of let-7a-5p and its overexpression reversed the effect of let-7a-5p on the proliferation, migration, and apoptosis in ox-LDL-treated HVSMCs. Also, circ_0002984 positively regulated KLF5 expression by absorbing let-7a-5p. The promotion effect of circ_0002984 on the proliferation and migration of ox-LDL-treated HVSMCs was reversed by KLF5 silencing. Taken together, depletion of circ_0002984 inhibited the proliferation and migration of ox-LDL-stimulated HVSMCs, which might be achieved by modulating the let-7a-5p/KLF5 axis.
环状 RNA（circRNAs）在动脉粥样硬化（AS）的进展中起着重要作用。本研究旨在探讨 circ_0002984 在氧化型低密度脂蛋白（ox-LDL）介导的人血管平滑肌细胞（HVSMCs）中的确切作用和机制。通过用 ox-LDL 处理 HVSMCs 构建平滑肌细胞表型转换模型。通过实时定量 PCR 或 Western blot 检测 circ_0002984、let-7a-5p 和 Kruppel 样因子 5（KLF5）的水平。通过细胞计数试剂盒-8（CCK-8）、EdU 染色、划痕愈合试验、Transwell 试验和流式细胞术检测细胞增殖、迁移和凋亡。通过 Western blot 检测裂解的 caspase-3 和 KLF5 的表达。通过双荧光素酶报告基因检测或 RIP 试验验证 let-7a-5p 与 circ_0002984 或 KLF5 的关系。结果表明，在 AS 患者和 ox-LDL 处理的 HVSMCs 中，circ_0002984 和 KLF5 上调，而 let-7a-5p 下调。沉默 circ_0002984 抑制 ox-LDL 刺激的 HVSMCs 的增殖和迁移，并促进凋亡。此外，circ_0002984 海绵吸附 let-7a-5p 调节 ox-LDL 所致 HVSMCs 的增殖、迁移和凋亡。此外，KLF5 是 let-7a-5p 的靶基因，其过表达逆转了 let-7a-5p 对 ox-LDL 处理的 HVSMCs 的增殖、迁移和凋亡的影响。此外，circ_0002984 通过吸附 let-7a-5p 正向调节 KLF5 的表达。沉默 KLF5 逆转了 circ_0002984 对 ox-LDL 处理的 HVSMCs 增殖和迁移的促进作用。总之，circ_0002984 的耗竭抑制了 ox-LDL 刺激的 HVSMCs 的增殖和迁移，这可能是通过调节 let-7a-5p/KLF5 轴实现的。
