LncRNA TUG1 alleviates the injury of small intestinal epithelial cells induced by lipopolysaccharide via regulating microrNa-132-3P /SIRT1 / 中华急诊医学杂志

ABSTRACT

Objective:To investigate the role of LncRNA-TUG1 in the injury of intestinal epithelial cells induced by lipopolysaccharide (LPS).Methods:LPS was used to treat HIEC-6 human intestinal epithelial cells for 24 h to construct a sepsis injury model. Whole transcriptome RNA sequencing was used to analyze the expression changes of mRNA, microRNA and lncRNA in HIEC-6 cells after LPS treatment. Real-time fluorescence quantitative (qRT-PCR) and Western blot was performed to detect the expression changes of lncRNA-TUG1, microRNA-132-3p (miR-132-3p), SIRT1 mRNA and SIRT1 protein in HIEC-6 cells after LPS treatment. The expression levels of LncRNA-TUG1, miR-132-3p and SIRT1 were artificially changed by in vitro transfection. qRT-PCR and Western blot were used to confirm the regulatory effect of lncRNA-TUG1 on microRNA-132-3p and SIRT1. CCK-8 and flow cytometry were used to analyze the effects of LncRNA-TUG1, miR-132-3p and SIRT1 on the proliferation and apoptosis of HIEC-6 cells. The dual luciferase report analysis was used to verify the targeting relationship between LncRNA-TUG1, miR-132-3p and SIRT1. Statistical analysis was performed using SPSS 17.0, and differences between the two groups were compared using independent sample t test. Results:RNA sequencing results showed that the expressions of lncRNA-TUG1 and SIRT1 were decreased in HIEC-6 cells after LPS treatment ( t=3.26, P<0.05 and t=2.55, P<0.05), but the expression of miR-132-3p was increased ( t=4.12, P<0.05). In vitro cell experiments, the expression of lncRNA-TUG1 and SIRT1 were decreased in HIEC-6 cells treated with LPS ( t=5.69, P<0.05 and t=5.712, P<0.05), while the expression of miR-132-3p was increased ( t=3.88, P<0.05). Overexpression of lncRNA-TUG1 increased the proliferation rate ( t=6.55, P<0.05) and decreased the apoptosis rate ( t=3.94, P<0.05) of LPS-treated cells. Upregulation of lncRNA-TUG1 decreased the expression of miR-132-3p ( t=4.66, P<0.05), and increased the mRNA and protein levels of SIRT1 ( t=3.91, P<0.05). Transfection of miR-132-3P mimic could inhibit the mRNA ( t=4.08, P<0.05) and protein levels of SIRT1. In LPS-treated cells, the cells co-transfected with miR-132-3pmimic and siRNA-SIRT1 had a lower proliferation rate ( t=4.55, P<0.05 and t=5.67, P<0.05) and a higher apoptosis rate ( t=3.90, P<0.05 and t=4.22, P<0.05) than those transfected with only pcDNA3.1-lncRNA-TUG. Conclusions:lncRNA-TUG1 may act as a ceRNA to regulate miR-132-3p/SIRT1, therefore alleviating HIEC-6 cell injury caused by LPS. Intervention of lncRNA-TUG1/miR-132-3p/SIRT1 regulatory pathway may become a potential strategy to prevent sepsis-induced intestinal mucosal damage.