Silencing astrocyte elevated gene-1 attenuates lipopolysaccharide-induced inflammation and mucosal barrier injury in NCM460 cells by suppressing the activation of NLRP3 inflammasome.

Abstract

The effect of oncogene astrocyte-elevated gene-1 (AEG-1) on noncancerous colonic epithelial cell disease is rarely studied. We aim to investigate the role of AEG-1 in lipopolysaccharide (LPS)-induced inflammation and mucosal barrier injury, and their potential mechanisms. NCM460 cells were stimulated by different concentrations of LPS at 12 h or 24 h. Cell viability and the expression of AEG-1 was determined by CCK-8, qRT-PCR, and Western blotting. Silencing AEG-1 was successfully established. Reactive oxygen species (ROS) level and apoptosis were measured by flow cytometry. Enzyme-linked immunosorbent assay (ELISA) was performed to detect IL-1β and IL-18 levels. qRT-PCR and Western blot were performed to assess the mRNA and protein level of tight junction (TJ)-associated genes, NLRP3 inflammasome activation-related factors. Silencing AEG-1 decreased ROS production; cell apoptosis; and IL-1β, IL-18 release, compared to those treated by LPS. Up-regulation of ZO-1 and Occludin showed that siAEG-1 could protect mucosal barrier from LPS-injured. Silencing AEG-1 could significantly inhibit NLRP3 and cleaved caspase-1 expression in LPS stimulation environment. Silencing AEG-1 inhibited NLRP3 activation, while the activation of caspase-1 reduced the secretion of proinflammatory cytokines IL-1β and IL-18. However, overexpressing AEG-1 aggravated LPS-triggered injury and activation of NLRP3 inflammasome.