Department of Nursing, Tongling Vocational and Technical College, No. 2689, Cuihu 4th Road, Tongguanshan District, Tongling City, 244000, Anhui Province, China.
Stroke Center, Tongling People's Hospital, Tongling, Anhui, China.
Metab Brain Dis. 2022 Jan;37(1):253-263. doi: 10.1007/s11011-021-00853-x. Epub 2021 Oct 27.
Dysfunction of vascular smooth muscle cells (VSMCs) plays a critical role in the development of intracranial aneurysm (IA). Here, we explored the detailed role and mechanism of circular RNA (circRNA) LIF receptor subunit alpha (circLIFR, circ_0072309) in human umbilical artery smooth muscle cells (HUASMCs). CircLIFR, microRNA (miR)-1299 and kinase insert domain receptor (KDR) expression levels were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot assays. Cell proliferation was assessed by Cell Counting Kit-8 (CCK-8) and 5-Ethynyl-2'-Deoxyuridine (EdU) assays. Cell migration was gauged by wound-healing and transwell assays. Cell invasion and apoptosis were detected by transwell assay and flow cytometry, respectively. Direct relationship between miR-1299 and circLIFR or KDR was verified by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. CircLIFR and KDR were down-regulated and miR-1299 was up-regulated in the artery wall tissues and ASMCs of IA patients. Enforced expression of circLIFR enhanced HUASMC proliferation, migration, invasion, and impeded apoptosis. Mechanistically, circLIFR directly targeted miR-1299, and miR-1299 was a downstream mediator of circLIFR in regulating the proliferation, migration, invasion and apoptosis of HUASMCs. KDR was identified as a direct and functional target of miR-1299 in HUASMCs. Furthermore, circLIFR was a post-transcriptional regulator of KDR expression through miR-1299. Our findings suggest that circLIFR, an underexpressed circRNA in IA, can regulate the proliferation, migration, invasion and apoptosis of HUASMCs depending on the miR-1299/KDR axis.
血管平滑肌细胞（VSMCs）功能障碍在颅内动脉瘤（IA）的发展中起着关键作用。在这里，我们探讨了环状 RNA（circRNA）LIF 受体亚基α（circLIFR，circ_0072309）在人脐动脉平滑肌细胞（HUASMCs）中的详细作用和机制。通过定量实时聚合酶链反应（qRT-PCR）和 Western blot 分析评估 circLIFR、微小 RNA（miR）-1299 和激酶插入结构域受体（KDR）的表达水平。通过细胞计数试剂盒-8（CCK-8）和 5-乙炔基-2'-脱氧尿苷（EdU）测定评估细胞增殖。通过划痕愈合和 Transwell 测定评估细胞迁移。通过 Transwell 测定和流式细胞术分别检测细胞侵袭和细胞凋亡。通过双荧光素酶报告和 RNA 免疫沉淀（RIP）测定验证 miR-1299 与 circLIFR 或 KDR 之间的直接关系。IA 患者的动脉壁组织和 ASMCs 中，circLIFR 和 KDR 下调，miR-1299 上调。强制表达 circLIFR 增强了 HUASMC 的增殖、迁移、侵袭，并抑制了凋亡。机制上，circLIFR 直接靶向 miR-1299，miR-1299 是 circLIFR 调节 HUASMC 增殖、迁移、侵袭和凋亡的下游介质。KDR 被鉴定为 HUASMCs 中 miR-1299 的直接和功能靶标。此外，circLIFR 通过 miR-1299 作为 KDR 表达的转录后调节剂。我们的研究结果表明，IA 中低表达的 circRNA circLIFR 可以通过 miR-1299/KDR 轴调节 HUASMC 的增殖、迁移、侵袭和凋亡。
