Long non-coding RNA RP11-490M8.1 inhibits lipopolysaccharide-induced pyroptosis of human umbilical vein endothelial cells via the TLR4/NF-κB pathway

Background and aims: Pyroptosis is a relatively newly discovered form of programmed cell death that plays an important role in the development of atherosclerosis. Many studies have reported that lncRNAs participated in the regulation of atherosclerosis development. However, the regulatory mechanism of lncRNAs in pyroptosis must be studied further. Methods: In a previous study, microarray analysis was used to detect the lncRNA expression profile in three human advanced atherosclerotic plaques and three normal arterial intimae. In the present research, in vitro assays were performed to investigate the role of lncRNA RP11-490M8.1 on pyroptosis. The relative gene mRNA and lncRNA expression levels were tested by quantitative real-time PCR, and protein levels were evaluated by western blot analysis. The RNA hybrid structure was analyzed using the DINAMelt server. Results: The lncRNA RP11-490M8.1 was significantly downregulated in atherosclerotic plaques and serum. Lipopolysaccharide (LPS) markedly reduced the expression of lncRNA RP11-490M8.1 and induced pyroptosis by increasing the mRNA and protein levels of NLRP3, caspase-1, ASC, IL-1 beta, and IL-18 in HUVECs. The promotion effects of LPS on pyroptosis were markedly suppressed by overexpression of lncRNA RP11-490M8.1. In addition, LPS increased the mRNA and protein levels of TLR4 and NF-kappa B, which was also markedly offset by overexpression of lncRNA RP11-490M8.1. Conclusions: These findings indicated that lncRNA RP11-490M8.1 inhibited LPS-induced pyroptosis via the TLR4/NF-kappa B pathway. Thus, lncRNA RP11-490M8.1 may provide a therapeutic target to ameliorate atherosclerosis.