Dexamethasone down-regulates the expression of microRNA-155 in the livers of septic mice

• Published in: PloS one Vol. 8; no. 11; p. e80547
• Main Authors: Wang, Zhong-hua, Liang, Yan-bing, Tang, Hao, Chen, Zhi-bin, Li, Zhen-yu, Hu, Xu-chu, Ma, Zhong-fu
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 11.11.2013; Public Library of Science (PLoS)
• Subjects: Alanine Transaminase - metabolism; Animal tissues; Animals; Apoptosis; B cells; Central nervous system depressants; Cytokines; Dexamethasone; Dexamethasone - pharmacology; Dexamethasone - therapeutic use; Female; Gene expression; Hospitals; Immunity; Infection; Inflammation; Interleukin-10 - metabolism; Interleukin-6 - metabolism; Internal medicine; Kinases; Laboratory animals; Lipopolysaccharides; Lipopolysaccharides - pharmacology; Liver; Liver - drug effects; Liver - metabolism; Medicine; Mice; Mice, Inbred BALB C; MicroRNA; MicroRNAs; MicroRNAs - genetics; miRNA; Mitogens; Pathogens; Ribonucleic acid; RNA; RNA polymerase; Rodents; Sepsis; Sepsis - chemically induced; Sepsis - immunology; Sepsis - metabolism; Steroids; Steroids (Organic compounds); Transcription factors; Tumor Necrosis Factor-alpha - metabolism; China
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0080547

To investigate the expression of microRNA-155 (miRNA-155) in the livers of mice with lipopolysaccharide (LPS)-induced sepsis and to determine the role of dexamethasone (DXM) in the regulation of miRNA-155 expression, we pretreated mice with or without DXM prior to LPS exposure. Our study demonstrated that the expression of miRNA-155 and inflammatory factors increased in the liver tissues of mice with LPS-induced sepsis and that DXM down-regulated their expression in a dose-dependent manner. Moreover, DXM alone inhibited the expression of miRNA-155 to below the baseline level, but did not impact the expression of inflammatory factors, suggesting that the down-regulation of miRNA-155 by DXM may partially, but not completely, depend on the suppression of pro-inflammatory cytokines by DXM. Our data indicate that the overexpression of miRNA-155 in the livers of mice with LPS-induced sepsis may play an important role in the pathological processes of sepsis and that the down-regulation of miRNA-155 by DXM may be a novel mechanism regulating inflammation and immunity.