miR-488 mediates negative regulation of the AKT/NF-κB pathway by targeting Rac1 in LPS-induced inflammation

J Cell Physiol. 2020 May;235(5):4766-4777. doi: 10.1002/jcp.29354. Epub 2019 Oct 31.

Abstract

Endometritis is an inflammatory change in the structure of the endometrium due to various causes and is a common cause of infertility. Studies have confirmed that microRNAs (miRNAs) play a key regulatory role in various inflammatory diseases. However, the miRNA-mediated mechanism of endometrial inflammation induced by lipopolysaccharides (LPS) remains unclear. In this study, real-time quantitative polymerase chain reaction, Western blot analysis, immunofluorescence and Rac family small GTPase 1 (Rac1) interference were used to reveal the overexpression of miR-488 in the LPS-induced bovine uterus, and the effect of protein kinase B κ-light chain enhancement of the nuclear factor-activated B cells (AKT/NF-κB) pathway in intimal epithelial cells. The results showed that the expression of inflammatory cytokines such as interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α in the experimental group was significantly lower than that in the control group when miR-488 was overexpressed. Similar results were observed in the expression levels of p-AKT, p-IKK, and p-p65 proteins. In addition, the dual-luciferase reporter system confirmed that miRNA-488 may directly target the 3'-untranslated region of Rac1. In turn, the expression of Rac1 was inhibited. Moreover, the nuclear translocation of NF-κB was inhibited, and meanwhile, the accumulation of reactive oxygen species (ROS) in the cells was reduced. Thus, we provide basic data for the negative regulation of miR-488 in LPS-induced inflammation by inhibiting ROS production and the AKT/NF-kB pathway in intimal epithelial cells.

Keywords: AKT/NF-κB; ROS; endometritis; lipopolysaccharide; miR-488.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cattle
  • Cytokines / genetics
  • Cytokines / metabolism
  • Disease Models, Animal
  • Endometriosis / chemically induced
  • Endometriosis / enzymology*
  • Endometriosis / genetics
  • Endometriosis / pathology
  • Endometrium / enzymology*
  • Endometrium / pathology
  • Epithelial Cells / enzymology*
  • Epithelial Cells / pathology
  • Female
  • Gene Expression Regulation
  • HEK293 Cells
  • Humans
  • Lipopolysaccharides
  • Mice, Inbred BALB C
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • NF-kappa B / metabolism*
  • Neuropeptides / genetics
  • Neuropeptides / metabolism*
  • Phosphorylation
  • Proto-Oncogene Proteins c-akt / metabolism*
  • Reactive Oxygen Species / metabolism
  • Signal Transduction
  • rac1 GTP-Binding Protein / genetics
  • rac1 GTP-Binding Protein / metabolism*

Substances

  • Cytokines
  • Lipopolysaccharides
  • MIRN488 microRNA, mouse
  • MicroRNAs
  • NF-kappa B
  • Neuropeptides
  • Rac1 protein, mouse
  • Reactive Oxygen Species
  • lipopolysaccharide, E coli O55-B5
  • Proto-Oncogene Proteins c-akt
  • rac1 GTP-Binding Protein