Long noncoding RNA NKILA alleviates lipopolysaccharide-induced bronchial epithelial cell injury by targeting miR-1236-3p

Abstract

Objective To investigate the protective effect of long noncoding RNA (lncRNA) NKILA against lipopolysaccharide (LPS)-induced injury of bronchial epithelial cells and explore the mechanism. Methods Bronchial epithelial cell line 16HBE was challenged with 50 μg/mL LPS for 24 h, and the changes in cellular expression levels of lncRNA NKILA and miR-1236-3p were detected using real-time quantitative PCR (qRT-PCR). 16HBE cells were transfected with pcDNA-NKILA and anti-miR-1236-3p to investigate the effects of lncRNA NKILA overexpression and miR-1236-3p interference on LPS-induced cell injury. Flow cytometry and Western blotting were used to determine the apoptosis rate and the expressions of apoptosis-related proteins Bcl-2 and Bax in the transfected cells, respectively; the levels of interleukin 6 (IL-6), IL-13, and tumor necrosis factor-α (TNF-α) in the supernatant were measured using ELISA. A dual-luciferase reporter assay was used to analyze the targeting relationship between lncRNA NKILA and miR-1236-3p. Results Compared with the control cells, 16HBE cells challenged with LPS showed significantly down-regulated expressions of lncRNA NKILA and Bcl-2 protein (P < 0.05) and up-regulated expressions of miR-1236-3p and Bax protein (P < 0.05), with significantly increased cell apoptosis rate and levels of the inflammatory factors IL-6, IL-13 and TNF-α in the supernatant (P < 0.05). Over-expression of lncRNA NKILA or interference of miR-1236-3p obviously ameliorated LPS-induced inflammatory injury and inhibited apoptosis of 16HBE cells. LncRNA NKILA negatively regulated the expression of miR-1236-3p, and over-expression of miR-1236-3p reversed the effects of lncRNA NKILA over-expression on inflammation and apoptosis of LPS-treated 16HBE cells. Conclusion LncRNA NKILA reduces the release of inflammatory factors and inhibits cell apoptosis in LPS-treated 16HBE cells by targeting miR-1236-3p for negative regulation of the latter.

Keywords

• bronchial epithelial cells
• 16hbe cells
• lipopolysaccharide
• long noncoding rna nkila
• mir-1236-3p
• injury
• apoptosis