Lymphotoxin beta receptor is associated with regulation of microRNAs expression and nuclear factor-kappa B activation in lipopolysaccharides (LPS)-stimulated vascular smooth muscle cells

Background: The aim of present study is to investigate the role of lymphotoxin beta receptor (Lt beta r) in lipopolysaccharides (LPS)-induced inflammation in vascular smooth muscle cells (VSMCs) and whether its effects are mediated by modulating microRNAs (miRNAs) and nuclear factor-kappa B (NF-kappa B). Methods: Mouse aortic smooth muscle cell (SMC) line (MOVAS cells) were transduced with short hairpin Lt beta r (shLt beta r) and mRNA and protein expression level of Lt beta r were measured by qPCR and Western blot in shLt beta r-transduced cells. Lentiviral vector-transduced (control) and lentiviral vector/ shLt beta r-transduced MOVAS cells were stimulated with LPS (1 mu g/mL) for 0, 16, or 24 h. Then the mRNA and protein levels of Lt beta r, interleukin-18 (IL-18), p-p65, p65 and vascular cell adhesion molecule 1 (VCAM-1) were measured by real-time quantitative polymerase chain reaction (qPCR), Western blot and enzyme-linked immunosorbent assay (ELISA). Different miRNAs expression in LPS-stimulated normal and shLt beta r-transduced cells were detected by small RNA sequencing (smRNA-seq). Results: The mRNA and protein expression of Lt beta r was significantly downregulated in shLt beta r-transduced cells. LPS-increased the mRNA and protein levels of Lt beta r, IL-18, p-p65 and VCAM-1 in were attenuated by shLt beta r transducing compared with LPS-stimulated control group. Moreover, LPS treatment induced 10 upregulated and 64 downregulated miRNAs in shLt beta r-transduced cells compared with control cells. Moreover, miR-146b-5p and miR-27a-5p levels were significantly decreased in shLt beta r-transduced cells. Conclusions: Our results show for the first time that the role of Lt beta r in regulating inflammatory response in LPS-stimulated VSMCs via modulating miRNAs and NF-kappa B pathway. Our findings might provide valuable information with respect to better understanding in the treatment of cardiovascular diseases, such as atherosclerosis.