ATP2B1-AS1 exacerbates sepsis-induced cell apoptosis and inflammation by regulating miR-23a-3p/TLR4 axis

Abstract

Background: Sepsis is a life-threatening disease with dominant mortality. Its early diagnosis and treatment can improve prognosis and reduce mortality. Long noncoding RNAs (lncRNAs) ATPase plasma membrane Ca2+ transporting 1 antisense RNA 1 (ATP2B1-AS1) is dysregulated and is involved in the progression of various diseases. Nevertheless, the role of ATP2B1-AS1 in sepsis remains unclear. Methods: A human monocytic cell line, THP-1 cells, was stimulated to induce a model of sepsis in vitro. The levels of ATP2B1-AS1, miR-23a-3p, and TLR4 were assessed by real-time quantitative polymerase chain reaction. The role of ATP2B1-AS1 in cell apoptosis and inflammation was explored by flow cytometry, Western blot analysis and enzyme-linked immunosorbent serologic assay. The binding sites between ATP2B1-AS1 and miR-23a-3p, and between miR-23a-3p and TLR4 were predicted by BiBiServ and the Encyclopedia of RNA Interactomes (ENCORI) online sites, respectively, and confirmed by the luciferase assay. Results: The level of ATP2B1-AS1 was increased in lipopolysaccharide (LPS)-treated THP-1 cells. LPS increased apoptosis ratio, relative protein expressions of pro-apoptotic factors, and relative messenger RNA (mRNA) level and concentrations of pro-inflammatory cytokines, but decreased the relative expression of anti-apoptosis protein and relative mRNA level and concentrations of anti-inflammatory factor. All these alterations were reversed with transfection of shATP2B1-AS1 into THP-1 cells. Moreover, ATP2B1-AS1 directly bound miR-23a-3p and negatively modulated the level of miR-23a-3p. Meanwhile, TLR4 was directly targeted by miR-23a-3p, and negatively and positively modulated by miR-23a-3p and ATP2B1-AS1, respectively. Conclusion: ATP2B1-AS1 aggravated apoptosis and inflammation by modulating miR-23a-3p/TLR4 axis in LPS-treated THP-1 cells.