MicroRNA-25-5p negatively regulates TXNIP expression and relieves inflammatory responses of brain induced by lipopolysaccharide

Abstract

Sepsis is one of the most common causes of death in patients suffering from severe infection or injury. Currently, a specific effective therapy remains to be established. In the present study, miR-25-5p, miR-105, miR-106b-5p, miR-154-3p, miR-20b-5p, miR-295-3p, miR-291-3p, miR-301b, miR-352, and miR-93-5p were predicted to target TXNIP mRNA from the databases of miRDB, Targetscan, and microT-CDS. The luciferase reporter assay confirmed that miR-25-5p negatively regulates TXNIP expression. The ELISA analyses and western blotting demonstrated that miR-25-5p downregulated the production of IL-1β, IL-6, IL-8, and TNF-α in lipopolysaccharide (LPS)-stimulated cells or rats, as well as the protein levels of TXNIP, NLRP3, and cleaved caspase-1. In addition, miR-25-5p increased the cell viability and decreased the apoptosis in LPS-stimulated CTX TNA2 cells and reduced the abnormal morphology of the brain in LPS-stimulated rats. Besides, miR-25-5p decreased the relative mean fluorescence intensity of DCF in LPS-stimulated CTX TNA2 cell, apoptosis, and protein levels of MnSOD and catalase in LPS-stimulated brains. These findings indicate that miR-25-5p downregulated LPS-induced inflammatory responses, reactive oxygen species production, and brain damage, suggesting that miR-25-5p is a candidate treatment for septic encephalopathy.