circRNA‑0006896‑miR1264‑DNMT1 axis plays an important role in carotid plaque destabilization by regulating the behavior of endothelial cells in atherosclerosis

Abstract

Atherosclerosis (AS) is a chronic inflammatory disease of the vascular wall with multiple causes. AS is the primary pathological basis of cardiovascular disease and stroke. Moreover, carotid plaque rupture and thrombus formation are the main causes of ischemic stroke. Therefore, understanding the formation of carotid plaques may help improve the prediction and prevention of cardiovascular and cerebrovascular events. Endothelial cell dysfunction results in re-endothelialization and angiogenesis in atherosclerotic plaques, thus promoting plaque destabilization. The aim of the present study was to evaluate the effect of circular RNA (circRNA) molecules in serum exosomes (serum-Exos) from patients with stable plaque atherosclerosis (SA) and unstable/vulnerable plaque atherosclerosis (UA). Specifically, the effect of circRNA on human umbilical vein endothelial cell (HUVEC) behavior and the mechanisms underlying plaque destabilization in AS were evaluated. Serum-Exos were isolated, then identified using transmission electron microscopy, nanoparticle tracking analysis and western blotting. The serum-Exo-circRNA expression profile of patients with SA or UA was investigated using a circRNA array. The relationship between circRNA-006896 in serum-Exos and biochemical parameters of patients with SA and UA were analyzed using Spearman's correlation. In addition, HUVECs were incubated with serum-Exos for in vitro functional assays. The present study demonstrated that circRNAs expression profiles in SA and UA serum-Exos were significantly different, indicating a potential role for circRNAs in carotid plaque destabilization. The expression of circRNA-0006896 was positively correlated with triglyceride, low-density lipoprotein cholesterol (LDL-C) and C-reactive protein levels, and negatively correlated with albumin levels in patients with UA. However, circRNA-0006896 expression was positively correlated with LDL-C in patients with SA. Using bioinformatic analysis, a competing endogenous RNA (ceRNA) network was selected to study the regulatory roles of circRNA-0006896 in serum-Exos. Additionally, in HUVECs treated with serum-Exos derived from patients with UA, the expression of circRNA-0006896 in HUVECs was upregulated. This was accompanied by decreased expression of microRNA-1264 and SOCS3, increased levels of DNMT1 and phosphorylated STAT3. HUVEC proliferation and migration were significantly increased in the UA group, compared with the mock and SA groups. This finding indicates that the circRNA-0006896-miR-1264-DNMT1 axis plays an important role in carotid plaque destabilization by regulating the behavior of endothelial cells. Moreover, it suggests that circRNA-0006896 may represent a therapeutic target for controlling JNK/STAT3 signaling in HUVECs. Thus, this study may provide insight on potential interventions against vulnerable plaque formation in patients with AS.

Roles and mechanisms of exosomal non-coding RNAs in human health and diseases

“…A few studies have found an association between exosomal circRNAs and the pathogenesis of AS. 444 , 445 Wen et al suggested that the expression of exosomal circRNA‑0006896 in circulation is positively associated with the levels of TG, LDL, and C-reactive protein (CRP) in patients with unstable plaque atherosclerosis. 445 The study also reported that the elevated circulating exosomal circRNA‑0006896 leads to high expression of circRNA‑0006896 in ECs, which results in an increases in capacities of proliferation and migration in ECs.…”

“… 444 , 445 Wen et al suggested that the expression of exosomal circRNA‑0006896 in circulation is positively associated with the levels of TG, LDL, and C-reactive protein (CRP) in patients with unstable plaque atherosclerosis. 445 The study also reported that the elevated circulating exosomal circRNA‑0006896 leads to high expression of circRNA‑0006896 in ECs, which results in an increases in capacities of proliferation and migration in ECs. This effect is accompanied with the upregulation of DNMT1 and phosphorylation of STAT3, which may provide protection against the vulnerable plaque formation.…”

“…This effect is accompanied with the upregulation of DNMT1 and phosphorylation of STAT3, which may provide protection against the vulnerable plaque formation. 445 …”

Impact of CircRNAs on Ischemic Stroke

“…We aimed to understand the role of circRNAs in serum exons of patients with stable plaque atherosclerosis (SA) and unstable/fragile plaque atherosclerosis (UA). Wen et al [ 26 ] studied the effect of circRNA on the behavior of human umbilical vein endothelial cells (HUVECs) and the mechanism of plaque instability in AS. They found significant differences in the expression profiles of circRNA in serum exons of SA and UA, indicating that circRNA may play a role in carotid plaque instability.…”

The potential role of hsa_circ_0001079 in androgenetic alopecia via sponging hsa‐miR‐136‐5p

“… 11 CircRNAs can regulate gene expression through multiple mechanisms, the most common of which is the large number of binding sites with sponging miRNAs, thus reducing the inhibitory effect of miRNA on target gene expression by competitively binding with miRNA. 12 Studies have shown that circRNAs play important roles in tumours, 13 cardiovascular diseases, 14 immune system diseases, etc. 15 , 16 However, the role of circRNAs in AGA is still unclear.…”