LncRNA-TCONS_00034812 is upregulated in atherosclerosis and upregulates miR-21 through methylation in vascular smooth muscle cells

LncRNA RASSF8-AS1 knockdown displayed antiproliferative and proapoptotic effects through miR-188-3p/ATG7 pathway in ox-LDL-treated vascular smooth muscle cells

BACKGROUND

Long noncoding RNA (lncRNA)-mediated changes in gene expression contribute to atherosclerosis (AS) development. However, the roles of numerous lncRNAs in AS have not been fully elucidated. Here, we aimed to investigate the potential role of lncRNA RASSF8-AS1 (RASSF8-AS1) in autophagy of human aortic vascular smooth muscle cells (HA-VSMCs).

METHODS

RASSF8-AS1 expression in patients with AS was extracted from the Gene Expression Omnibus (GEO) database. RASSF8-AS1 and microRNA-188-3p (miR-188-3p) expression was analyzed in 20 enrolled patients with AS. HA-VSMCs were treated with oxidized low-density lipoprotein (ox-LDL) (25, 50, 75, and 100 µg/mL) for 24 h. Loss- or gain-of-function of RASSF8-AS1, miR-1883p, and autophagy-related 7 (ATG7) was studied using the transfected HA-VSMCs. Cell viability was assessed using Cell Counting Kit-8 (CCK-8). Apoptosis was detected with annexin V-fluorescein isothiocyanate (FITC) and propidium iodide (PI). Relative luciferase reporter assay was used to confirm the targeting relationship of miR-188-3p to RASSF8-AS1 or ATG7. Gene expression was detected by quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot.

RESULTS

RASSF8-AS1 was enriched in the serum of patients with AS and ox-LDL-treated HA-VSMCs. Ox-LDL induced proliferation and autophagy while inhibiting the apoptosis of HA-VSMCs, which was abated by RASSF8-AS1 knockdown. RASSF8-AS1 downregulated miR-188-3p of ox-LDL-treated HA-VSMCs. RASSF8-AS1 knockdown caused an increase in miR-188-3p, which inhibited proliferation and autophagy and induced the apoptosis of ox-LDL-treated HA-VSMCs. miR-188-3p inhibited ATG7 expression in ox-LDL-treated HA-VSMCs. RASSF8-AS1 elevated ATG7 and induced autophagy through sponging miR-188-3p in ox-LDL-treated HA-VSMCs.

CONCLUSIONS

RASSF8-AS1 regulated autophagy by targeting miR-188-3p, a messenger RNA-binding miRNA that increases ATG7 level, which may be a new target molecule for the prevention and prognosis of AS.

Long noncoding RNA DANCR expression and its predictive value in patients with atherosclerosis

Long noncoding RNAs (lncRNAs) act crucial roles in the progression of vascular diseases, including atherosclerosis. This study aims to investigate the expression levels of the atherosclerosis-associated lncRNA DANCR in patients diagnosed with atherosclerosis and whether its abnormal expression affects the progress of atherosclerosis. The expression of DANCR in the serum samples of all study participants was quantified using RT-qPCR. Then, the predictive capacities of DANCR for the detection of atherosclerosis patients were evaluated via receiver operating characteristic (ROC) curve analysis. The effects of DANCR on vascular smooth muscle cells (VSMCs) proliferation and migration were then explored using cell counting kit-8 (CCK-8) and Transwell migration assays. The DANCR exhibited increased expression trends in patients with atherosclerosis than healthy controls. Moreover, there were differences in the levels of low-density lipoprotein cholesterol (LDL-C), homocysteine (Hcy), and C-reactive protein (CRP) between the healthy controls and atherosclerosis patients. The DANCR expression was positively correlated with serum LDL-C, Hcy, and CRP levels. DANCR expression could distinguish patients with atherosclerosis from healthy individuals with a high area under the ROC curve (AUC), sensitivity, and specificity. Additionally, knockdown of DANCR weakened the proliferative abilities and migration capacities of VSMCs. It was also shown that DANCR could compete with miR-335-5p binding. Herein, it appears that the LncRNA DANCR was closely associated with the progression of atherosclerosis by targeting miR-335-5p, which might be a potential detective predictor and target for the treatment of atherosclerosis.