Circular RNA circHIPK3 as a novel circRNA regulator of autophagy and endothelial cell dysfunction in atherosclerosis

Objective The aim of the study was to explore the role and mechanism of circHIPK3 in atherosclerosis. Materials and methods AS model was constructed in vivo and in vitro for high fat-fed and ox-LDL treatment. RT-PCR was used to assess the level of circHIPK3. The autophagy level of HUVECs was detected by Western blot, transmission electron microscopy, and LC3II fluorescence intensity. HUVECs lipid accumulation was assessed by oil red staining. Luciferase assay was performed to verify the relationship of circRNA and miRNA, miRNA, and target gene. Results The expression of circHIPK3 was downregulated in HFD mice, and ox-LDL treated HUVECs. The level of autophagy was decreased in AS, which was reversed by overexpression of circHIPK3. Meanwhile, forced expression of circHIPK3 would reduce the accumulation of lipid in HUVECs. Conclusions CircHIPK3 could inhibit lipid content in ox-LD-treated HUVECs via activating autophagy. This progression mechanism may target the miR-190b/ATG7 signal pathway, which indicates a suitable role in the pathogenesis of atherosclerosis.