mTOR signaling pathway regulation HIF-1 α effects on LPS induced intestinal mucosal epithelial model damage

BMC Mol Cell Biol. 2024 Apr 23;25(1):13. doi: 10.1186/s12860-024-00509-5.

Abstract

Background: Sepsis-induced small-intestinal injury is associated with increased morbidity and mortality. Our previous study and other papers have shown that HIF-1α has a protective effect on intestinal mucosal injury in septic rats. The purpose of this study is to further verify the protective effect of HIF-1α on intestinal mucosa and its molecular mechanism in vitro experiments.

Methods: Caco-2 cells were selected and experiment was divided into 2 parts. Part I: HIF-1α activator and inhibitor were used to treat lipopolysacchrides (LPS)-stimulated Caco-2 cells respectively, to explore the effect of HIF-1α on LPS induced Caco-2 cell epithelial model; Part II: mTOR activator or inhibitor combined with or without HIF-1α activator, inhibitor to treat LPS-stimulated Caco-2 cells respectively, and then the molecular mechanism of HIF-1α reducing LPS induced Caco-2 cell epithelial model damage was detected.

Results: The results showed that HIF-1α activator decreased the permeability and up regulated tight junction (TJ) expression, while HIF-1α inhibitor had the opposite effect with the HIF-1α activator. mTOR activation increased, while mTOR inhibition decreased HIF-1α protein and expression of its downstream target molecules, which can be attenuated by HIF-1α activator or inhibitor.

Conclusion: This study once again confirmed that HIF-1α alleviates LPS-induced mucosal epithelial model damage through P70S6K signalling pathway. It is of great value to explore whether HIF-2α plays crucial roles in the regulation of mucosal epithelial model functions in the future.

Keywords: Caco-2 cells; Hypoxia-inducible factor-1α; In vitro; LPS induced intestinal epithelial model injury; mTOR/P70S6K signalling pathway.

MeSH terms

  • Caco-2 Cells
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit* / metabolism
  • Intestinal Mucosa* / drug effects
  • Intestinal Mucosa* / metabolism
  • Lipopolysaccharides* / pharmacology
  • Signal Transduction* / drug effects
  • TOR Serine-Threonine Kinases* / metabolism

Substances

  • HIF1A protein, human
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Lipopolysaccharides
  • MTOR protein, human
  • TOR Serine-Threonine Kinases