Ubiquitin-independent degradation of Bim blocks macrophage pyroptosis in sepsis-related tissue injury

Cell Death Dis. 2024 Sep 30;15(9):703. doi: 10.1038/s41419-024-07072-z.

Abstract

Pyroptosis, a typical inflammatory cell death mode, has been increasingly demonstrated to have therapeutic value in inflammatory diseases such as sepsis. However, the mechanisms and therapeutic targets of sepsis remain elusive. Here, we reported that REGγ inhibition promoted pyroptosis by regulating members of the gasdermin family in macrophages. Mechanistically, REGγ directly degraded Bim, a factor of the Bcl-2 family that can inhibit the cleavage of GSDMD/E, ultimately preventing the occurrence of pyroptosis. Furthermore, cecal ligation and puncture (CLP)-induced sepsis model mice showed downregulation of REGγ at both the RNA and protein levels. Gasdermin-mediated pyroptosis was augmented in REGγ-knockout mice, and these mice exhibited more severe sepsis-related tissue injury. More importantly, we found that REGγ expression was downregulated in clinical sepsis samples, such as those from patients with Pseudomonas aeruginosa (PA) infection. Finally, PA-infected mice showed decreased REGγ levels in the lung. In summary, our study reveals that the REGγ-Bim-GSDMD/E pathway is a novel regulatory mechanism of pyroptosis in sepsis-related tissue injury.

MeSH terms

  • Animals
  • Autoantigens
  • Bcl-2-Like Protein 11* / genetics
  • Bcl-2-Like Protein 11* / metabolism
  • Disease Models, Animal
  • Gasdermins
  • Humans
  • Intracellular Signaling Peptides and Proteins / genetics
  • Intracellular Signaling Peptides and Proteins / metabolism
  • Macrophages* / metabolism
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout*
  • Phosphate-Binding Proteins / metabolism
  • Pore Forming Cytotoxic Proteins / metabolism
  • Proteasome Endopeptidase Complex
  • Proteolysis
  • Pseudomonas Infections / metabolism
  • Pseudomonas Infections / pathology
  • Pseudomonas aeruginosa / pathogenicity
  • Pyroptosis*
  • RAW 264.7 Cells
  • Sepsis* / metabolism
  • Sepsis* / pathology
  • Ubiquitin / metabolism

Substances

  • Bcl-2-Like Protein 11
  • Ki antigen
  • Phosphate-Binding Proteins
  • Ubiquitin
  • Intracellular Signaling Peptides and Proteins
  • Gsdmd protein, mouse
  • Gsdme protein, mouse
  • Pore Forming Cytotoxic Proteins
  • Gasdermins
  • Autoantigens
  • Proteasome Endopeptidase Complex