Atherosclerosis (AS) is a complex multifactorial and chronic inflammatory vascular disease that contributes to the development of cardiovascular diseases. Abnormal cellular proliferation in human umbilical vein endothelial cells (HUVECs) is a crucial element in AS development. In this study, we investigated the potential role of the long noncoding RNA LINC02381/ microRNA (miR)-491-5p/transcription factor 7 (TCF7) axis in regulating HUVEC injury in 30 participants suffering from AS and 30 healthy control participants. We established an in vitro model of AS in HUVECs using oxidized low-density lipoprotein (ox-LDL), and measured cellular mRNA and protein levels of LINC02381, miR-491-5p, and TCF7 in serum samples using reverse transcription-quantitative polymerase chain reaction and Western blotting assays. We evaluated cell viability, apoptosis, and inflammation using Cell Counting Kit-8, flow cytometry, and enzyme-linked immunosorbent assays, respectively. Moreover, we analyzed apoptosis-related protein expression using western blotting analysis and determined the association between miR-491-5p and LINC02381 or TCF7 using dual-luciferase reporter assay, RNA pull-down, and rescue experiments. We observed that LINC02381 was elevated, while miR-491-5p was downregulated in serum samples from participants with AS and in ox-LDL-treated HUVECs. LINC02381 knockdown was protective against HUVEC injury via miR-491-5p inhibition, which is its downstream target. Rescue experiments further demonstrated that miR-491-5p alleviated HUVEC injury by modulating TCF7. Thus, LINC02381 knockdown ameliorated HUVEC injury by regulating the miR-491-5p/TCF7 axis, which provides new insights into AS treatment strategies.

Background Deep vein thrombosis (DVT) is a vascular disease that has no effective treatment at present. Endothelial cells play a crucial role in the processes vasoconstriction, platelet activation, and blood coagulation and are an integral part of the vascular response to injury resulting in thrombus formation. Objective The aim of this study was to investigate the roles and mechanisms of long noncoding RNA LINC00659 (LINC00659) in endothelial cells. Methods The functions of LINC00659 and miR‐525‐5p on endothelial cells were explored by cell transfection assays, and the expression levels of LINC00659, miR‐525‐5p, and Bax in human umbilical vein endothelial cells (HUVECs) were assessed with reverse transcriptase‐quantitative polymerase chain reaction (RT‐qPCR). Binding sites of LINC00659 and miR‐525‐5p were subsequently analyzed with bioinformatics software, and validated with dual‐luciferase reporter gene assay. Effects of LINC00659 and miR‐525‐5p on proliferation and apoptosis of HUVECs were detected with MTT (3‐(45)‐dimethylthiahiazo (‐z‐y1)‐35‐di‐phenytetrazoliumromide) assay and flow cytometry. RT‐qPCR and western blot analysis were used to evaluate the mRNA and protein levels of apoptosis‐related markers Bcl‐2 and Bax in HUVECs. Results LINC00659 directly targeted and negatively regulated miR‐525‐5p, and Bax was a target of miR‐525‐5p. Upregulation of LINC00659 could inhibit proliferation and promote apoptosis of HUVECs, while the silencing of LINC00659 could increase the viability of HUVECs and inhibit apoptosis via upregulating miR‐525‐5p. Further mechanistic studies revealed miR‐525‐5p could negatively regulate Bax in HUVECs, and increased the viability of HUVECs and inhibited apoptosis by downregulating Bax expression. Conclusion LINC00659 played an important role in DVT by regulating the apoptosis of vascular endothelial cells through regulating miR‐525‐5p/Bax axis.