Exogenous autoinducer-2 alleviates intestinal damage in necrotizing enterocolitis via PAR2/MMP3 signaling pathway

Int Immunopharmacol. 2024 Sep 10:138:112567. doi: 10.1016/j.intimp.2024.112567. Epub 2024 Jun 30.

Abstract

Background: Imbalanced intestinal microbiota and damage to the intestinal barrier contribute to the development of necrotizing enterocolitis (NEC). Autoinducer-2 (AI-2) plays a crucial role in repairing intestinal damage and reducing inflammation.

Objective: This study aimed to investigate the impact of AI-2 on the expression of intestinal zonula occludens-1 (ZO-1) and occludin proteins in NEC. We evaluated its effects in vivo using NEC mice and in vitro using lipopolysaccharide (LPS)-stimulated intestinal cells.

Methods: Pathological changes in the intestines of neonatal mice were assessed using histological staining and scoring. Cell proliferation was measured using the cell counting kit-8 (CCK-8) assay to determine the optimal conditions for LPS and AI-2 interventions. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to analyze the mRNA levels of matrix metalloproteinase-3 (MMP3), protease activated receptor-2 (PAR2), interleukin-1β (IL-1β), and IL-6. Protein levels of MMP3, PAR2, ZO-1, and occludin were evaluated using western blot, immunohistochemistry, or immunofluorescence.

Results: AI-2 alleviated NEC-induced intestinal damage (P < 0.05) and enhanced the proliferation of damaged IEC-6 cells (P < 0.05). AI-2 intervention reduced the mRNA and protein expressions of MMP3 and PAR2 in intestinal tissue and cells (P < 0.05). Additionally, it increased the protein levels of ZO-1 and occludin (P < 0.05), while reducing IL-1β and IL-6 mRNA expression (P < 0.05).

Conclusion: AI-2 intervention enhances the expression of tight junction proteins (ZO-1 and occludin), mitigates intestinal damage in NEC neonatal mice and IEC-6 cells, potentially by modulating PAR2 and MMP3 signaling. AI-2 holds promise as a protective intervention for NEC. AI-2 plays a crucial role in repairing intestinal damage and reducing inflammation.

Keywords: Autoinducer-2; Matrix metalloproteinase-3; Necrotizing enterocolitis; Protease activated receptor-2; Tight junction.

MeSH terms

  • Animals
  • Animals, Newborn
  • Cell Line
  • Cell Proliferation / drug effects
  • Disease Models, Animal
  • Enterocolitis, Necrotizing* / drug therapy
  • Enterocolitis, Necrotizing* / metabolism
  • Enterocolitis, Necrotizing* / pathology
  • Homoserine / analogs & derivatives
  • Homoserine / pharmacology
  • Humans
  • Intestinal Mucosa / drug effects
  • Intestinal Mucosa / immunology
  • Intestinal Mucosa / metabolism
  • Intestinal Mucosa / pathology
  • Intestines / drug effects
  • Intestines / pathology
  • Lactones / pharmacology
  • Lipopolysaccharides
  • Matrix Metalloproteinase 3* / genetics
  • Matrix Metalloproteinase 3* / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Occludin / genetics
  • Occludin / metabolism
  • Receptor, PAR-2* / genetics
  • Receptor, PAR-2* / metabolism
  • Signal Transduction* / drug effects
  • Zonula Occludens-1 Protein / genetics
  • Zonula Occludens-1 Protein / metabolism

Substances

  • F2rl1 protein, mouse
  • Homoserine
  • Lactones
  • Lipopolysaccharides
  • Matrix Metalloproteinase 3
  • Mmp3 protein, mouse
  • Occludin
  • Receptor, PAR-2
  • Tjp1 protein, mouse
  • Zonula Occludens-1 Protein
  • N-octanoylhomoserine lactone