Department of Vascular Surgery, First Affiliated Hospital of Bengbu Medical College, Bengbu, China.
Vasc Med. 2023 Feb;28(1):6-17. doi: 10.1177/1358863X221137617.
Circular RNAs (circRNAs) have been implicated in the pathogenesis of atherosclerosis (AS) and the migration and proliferation of vascular smooth muscle cells (VSMCs) under oxidized low-density lipoprotein (ox-LDL). Here, we defined the exact action of human circ_0007478 in VSMC migration and proliferation induced by ox-LDL.
Human VSMCs (HVSMCs) were exposed to ox-LDL. Circ_0007478, microRNA (miR)-638, and rho-associated protein kinase 2 () levels were gauged by quantitative real-time PCR (qRT-PCR) and western blot. Cell viability and proliferation were assessed by MTT and EdU assays, respectively. Transwell assays were used to detect cell migration and invasion. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were used to evaluate the direct relationship between miR-638 and circ_0007478 or .
Our data indicated that circ_0007478 expression was augmented in AS serum samples and ox-LDL-treated HVSMCs. Depletion of circ_0007478 attenuated HVSMC proliferation, migration, and invasion induced by ox-LDL. Mechanistically, circ_0007478 targeted miR-638 by directly pairing to miR-638. Reduction of miR-638 reversed the effects of circ_0007478 depletion on ox-LDL-evoked proliferation, migration, and invasion in HVSMCs. was a direct miR-638 target and miR-638-mediated inhibition of relieved ox-LDL-evoked HVSMC proliferation, migration, and invasion. Furthermore, circ_0007478 was identified as a competing endogenous RNA (ceRNA) for miR-638 to modulate expression.
Our present study establishes an undescribed ceRNA regulatory network, in which circ_0007478 targets miR-638 to upregulate , thereby contributing to ox-LDL-induced proliferation and migration in HVSMCs.
环状 RNA（circRNAs）已被认为与动脉粥样硬化（AS）的发病机制以及氧化型低密度脂蛋白（ox-LDL）下血管平滑肌细胞（VSMCs）的迁移和增殖有关。在这里，我们确定了人 circ_0007478 在 ox-LDL 诱导的 VSMC 迁移和增殖中的确切作用。
将人血管平滑肌细胞（HVSMCs）暴露于 ox-LDL 中。通过实时定量 PCR（qRT-PCR）和 Western blot 测定 circ_0007478、microRNA（miR）-638 和 rho 相关蛋白激酶 2（）的水平。通过 MTT 和 EdU 测定分别评估细胞活力和增殖。使用 Transwell 测定法检测细胞迁移和侵袭。双荧光素酶报告和 RNA 免疫沉淀（RIP）测定用于评估 miR-638 与 circ_0007478 或 的直接关系。
我们的数据表明，circ_0007478 在 AS 血清样本和 ox-LDL 处理的 HVSMCs 中表达增加。circ_0007478 的耗竭减弱了 ox-LDL 诱导的 HVSMC 增殖、迁移和侵袭。机制上，circ_0007478 通过直接与 miR-638 配对靶向 miR-638。降低 miR-638 逆转了 circ_0007478 耗竭对 ox-LDL 诱导的 HVSMC 增殖、迁移和侵袭的影响。是 miR-638 的直接靶标，miR-638 介导的对的抑制缓解了 ox-LDL 诱导的 HVSMC 增殖、迁移和侵袭。此外，circ_0007478 被鉴定为 miR-638 的竞争性内源性 RNA（ceRNA），以调节的表达。
本研究建立了一个未描述的 ceRNA 调控网络，其中 circ_0007478 靶向 miR-638 上调，从而促进 ox-LDL 诱导的 HVSMC 增殖和迁移。
