miR‐222‐5p promotes dysfunction of human vascular smooth muscle cells by targeting RB1

Abstract

Background: Coronary atherosclerosis (AS) is characterized by the formation of plaque in the vessel wall. The structural and functional changes of vascular smooth muscle cells (VSMCs) can promote plaque formation and induce plaque instability. Objective: To investigate the functions and mechanism of miR-222-5p in VSMCs under the treatment of oxidized low-density lipoprotein (ox-LDL). Methods: miR-222-5p expression in ox-LDL-treated VSMCs and the serum of Apolipoprotein E (ApoE) knockout mice was detected by reverse transcription quantitative polymerase chain reaction. The viability and migration of VSMCs were detected by Cell Counting Kit-8 and Transwell assays. Protein levels of proliferation and migration-related factors were evaluated by western blotting. Luciferase reporter assays were performed to explore the binding between miR-222-5p and retinoblastoma susceptibility protein (RB1) gene in VSMCs. ApoE-knockout mice were infected with the lentivirus inhibiting miR-222-5p expression to explore the effect of miR-222-5p on pathological changes. Hematoxylin and eosin (H&E) staining, trichrome staining, and Oil Red O staining were conducted to determine the necrotic core area and atherosclerotic lesion size in the ascending aorta of ApoE-knockout mice. Results: With the accumulation of ox-LDL concentration and treatment time, miR-222-5p expression was gradually upregulated in VSMCs. Similarly, miR-222-5p expression was increased in the serum of ApoE-knockout mice. miR-222-5p knockdown inhibited the proliferative and migratory abilities of ox-LDL-treated VSMCs, and the inhibitory effect on cellular behaviors was then significantly reversed by coknockdown of RB1. RB1 is a downstream target gene of miR-222-5p, and miR-222-5p bound with 3 0 -untranslated region of RB1 in VSMCs. We further confirmed that miR-222-5p knockdown alleviated pathological changes and inhibited lipid deposition in the serum of ApoE-knockout mice in vivo. Conclusion: miR-222-5p accelerates the dysfunction of VSMCs and promotes pathological changes and lipid deposition in ApoE-knockout mice by targeting RB1. The study may provide novel therapeutic targets for AS.

Effect of miR-663 on atherosclerosis by regulating the proliferation of vascular smooth muscle cells in lipid plaques

“…Several miRNAs are differentially expressed in AS plaques, and Ox-LDL treatment in vitro, likewise, can lead to differential expression of miRNAs in VSMCs. [44][45][46] Consistently, our results also reflected increased VSMC proliferation and declined miR-663 expression at 12-48 h, and the highest cell viability and lowest miR-663 expression at 48 h. Jointly, miR-663 was downregulated in VSMCs induced by Ox-LDL. Ox-LDL was an important cardiovascular risk factor and had been proved to stimulate the proliferation of VSMCs.…”

MiR-497-5p regulates ox-LDL-induced dysfunction in vascular endothelial cells by targeting VEGFA/p38/MAPK pathway in atherosclerosis

“…MiR-497-5p helps regulate genes, and we found ox-LDL affects it mostly through oxidative stress, triggering pathways like NF-κB and MAPK that change miRNA levels, including miR-497-5p [ 24 , 25 ]. However, ox-LDL's effect on miR-497-5p might also involve lipid changes or other stress pathways [ 26 , 27 ], showing the complex ways ox-LDL and miR-497-5p interact in endothelial cells, with oxidative stress being a key but not the only factor.…”

miR-200c-3p, miR-222-5p, and miR-512-3p Constitute a Biomarker Signature of Sorafenib Effectiveness in Advanced Hepatocellular Carcinoma

“…Regarding cell cycle, one of the key regulators of cell cycle progression is RB1, which has been characterized as a target of miR-222-5p. By means of regulating RB1, miR-222-5p contributes to migration and invasion, and also to altered lipid metabolism [ 59 ]. Additionally, miR-222-5p repressed SOX9, whose down-regulation during YAP signaling has been proposed as a mechanism of malignancy in HCC [ 60 ].…”