The correlation between inflammatory injury induced by LPS and RAS in EpH4-Ev cells

Int Immunopharmacol. 2017 May:46:23-30. doi: 10.1016/j.intimp.2017.02.016. Epub 2017 Feb 27.

Abstract

Renin-angiotensin system (RAS) plays an important role of regulating inflammatory injury. However, it is not clear about the correlation between renin-angiotensin system (RAS) and inflammation induced by LPS in mammary gland cells. So immunofluorescence was performed to verify the ACE2 expression in mammary gland cells. MTT assay was performed to detect cell viability. ELISA was performed to detect cytokines in cell supernatant. Western Blot was performed to analyze RAS levels and ACE2 level change was observed by immunofluorescence. The TLR4 level and p65 phosphorylation were detected by Western Blot. The ACE2 protein intensively located on the cell membrane. According to the results of MTT assay and TNF-α level, the injury was evidently induced by high concentration LPS after 9h. The TNF-α, IL-6, IL-8, ACE, AT1R and AngII had an increasing expression with the rise of cell injury. In contrast, the MasR, Ang1-7 and ACE2 had a declining expression with the increase of cell injury degree. The TLR4 level and p65 phosphorylation in high concentration LPS group was significantly higher than that of control group. These results suggest that a valid inflammatory injury was induced after the cells were treated by high concentration of LPS for 9h. Meanwhile, the ACE/AngII/AT1R axis was activated and the ACE2/Ang1-7/MasR axis was depressed.

Keywords: ACE2; Inflammatory injury; LPS; Mammary gland cells; RAS.

MeSH terms

  • Angiotensin II / metabolism
  • Angiotensin-Converting Enzyme 2
  • Animals
  • Cell Line
  • Epithelial Cells / immunology*
  • Female
  • Humans
  • Inflammation / immunology*
  • Interleukin-6 / metabolism
  • Interleukin-8 / metabolism
  • Lipopolysaccharides / immunology
  • Mammary Glands, Human / pathology*
  • Mice
  • NF-kappa B / metabolism
  • Peptidyl-Dipeptidase A / genetics
  • Peptidyl-Dipeptidase A / metabolism*
  • Proto-Oncogene Mas
  • Renin-Angiotensin System / immunology*
  • Signal Transduction
  • Toll-Like Receptor 4 / metabolism
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Interleukin-6
  • Interleukin-8
  • Lipopolysaccharides
  • NF-kappa B
  • Proto-Oncogene Mas
  • Tlr4 protein, mouse
  • Toll-Like Receptor 4
  • Tumor Necrosis Factor-alpha
  • Angiotensin II
  • Peptidyl-Dipeptidase A
  • ACE2 protein, human
  • Ace2 protein, mouse
  • Angiotensin-Converting Enzyme 2