Dexamethasone down-regulates the expression of microRNA-155 in the livers of septic mice.
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.
Department of Intensive Care Unit, Guangdong General Hospital, Guangzhou, Guangdong, China.
Zhong-hua
ZH
Wang
Yan-bing
YB
Liang
Hao
H
Tang
Zhi-bin
ZB
Chen
Zhen-yu
ZY
Li
Xu-chu
XC
Hu
Zhong-fu
ZF
Ma
D000410:Alanine Transaminase / Q000378:metabolism; D000818:Animals; D003907:Dexamethasone / Q000494:pharmacology* / Q000627:therapeutic use*; D005260:Female; D016753:Interleukin-10 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D008099:Liver / Q000187:drug effects* / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D035683:MicroRNAs / Q000235:genetics*; D018805:Sepsis / Q000139:chemically induced / Q000276:immunology / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D015850:Interleukin-6; D008070:Lipopolysaccharides; D035683:MicroRNAs; C532623:Mirn155 microRNA, mouse; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D003907:Dexamethasone; D000410:Alanine Transaminase