Long Noncoding RNA MALAT1 Regulates the Progression of Atherosclerosis by miR-330-5p/NF-κB Signal Pathway

Long non-coding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) was reported to be related to atherosclerosis (AS) progression. However, the underlying mechanism of MALAT1 in AS remains unknown. Quantitative real-time polymerase chain reaction was performed to detect the expression of MALAT1 and miR-330-5p. Western blot was applied to assess the protein levels of cluster of differentiation 36, interleukin-1β, interleukin-6 and tumor necrosis factor-α, phosphorylation of nuclear factor kappa-B inhibitor alpha and phosphorylation of p65. Flow cytometry assay, cell counting kit 8 assay, triglyceride, and total cholesterol detection assays were used to detect the apoptosis, viability, and lipid indexes of THP-1 macrophages-derived foam cells. Online database starbasev2.0 was used to predict the binding sequences between MALAT1 and miR-330-5p and it was verified by dual-luciferase reporter system and RNA immunoprecipitation assay. Besides, an AS mice model was used to evaluate the effect of MALAT1 in vivo. As a result, MALAT1 was overexpressed, whereas miR-330-5p was downregulated in THP-1 macrophages-derived foam cells. MiR-330-5p was a target of MALAT1. MALAT1 depletion inhibited cell formation, apoptosis, and inflammation in THP-1 macrophages-derived foam cells. Besides, MALAT1 overexpression promoted the inflammation in AS mice model, which promoted the pathogenesis of AS. Furthermore, miR-330-5p regulated the nuclear factor kappa light chain enhancer of activated B cells (NF-κB) pathway in THP-1 macrophages-derived foam cells. Moreover, MALAT1 regulated NF-κB signal pathway to mediate the pathogenesis of AS by sponging miR-330-5p. MALAT1 sponges miR-330-5p to activate NF-κB signal pathway in THP-1 macrophages-derived foam cells. This finding may provide a novel biomarker for AS diagnosis.