Typically inhibiting USP14 promotes autophagy in M1-like macrophages and alleviates CLP-induced sepsis

Cell Death Dis. 2020 Aug 20;11(8):666. doi: 10.1038/s41419-020-02898-9.

Abstract

Macrophages, with diverse functions and variable phenotypes, are considered as an important executor of inflammatory diseases. And it has been proved that autophagy is deeply connected with the development of inflammation, while the exact regulatory mechanism still remains unclear, and the application of autophagy regulators in anti-inflammation needs to be further confirmed. Here, we firstly verified that neochromine S5 (hereinafter referred to as S5) significantly inhibited M1-like macrophage polarization with decrease of the proinflammatory cytokines and downregulation of NF-κB and STAT1 signals. Then, in vivo experiments demonstrated S5 improved cecal ligation and puncture (CLP)-induced sepsis specially based on the regulation of M1-like macrophages. Mechanistic studies indicated that S5 treatment dramatically upregulated cellular autophagy in M1-like macrophage. Furthermore, by multiple methods, S5 was revealed to directly bind with ubiquitin-specific proteases 14 (USP14) at Ser404, Phe405, and Cys414 by hydrogen bond to inhibit its deubiquitinating activity, and block USP14-TRAF6 (TNF receptor associated factor 6) interaction, subsequently promoting ubiquitination of Beclin1, interrupting Beclin1-Bcl2 interaction, and accumulating the autophagosome in macrophages, which finally resulted in the blockade of M1-like macrophage polarization. Animal experiments also confirmed the protection of S5 in CLP mice was dependent on activation of macrophage autophagy. What's more, as a novel USP14 inhibitor, S5 exhibited higher efficiency and safety than IU1, the known USP14 inhibitor. Therefore, this study has demonstrated that typically inhibiting USP14 promotes autophagy in M1-like macrophages and alleviates CLP-induced sepsis. Moreover, we provide a new candidate compound, S5, for sensitizing autophagy to interfere with the macrophage inflammation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Autophagy / physiology*
  • Beclin-1 / metabolism
  • Benzoxazines / chemical synthesis
  • Benzoxazines / pharmacology*
  • Chromones / chemical synthesis
  • Chromones / pharmacology*
  • Cytokines / metabolism
  • Female
  • Macrophage Activation / immunology
  • Macrophages / metabolism*
  • Macrophages / physiology
  • Mice
  • Mice, Inbred C57BL
  • NF-kappa B / metabolism
  • STAT1 Transcription Factor / metabolism
  • Sepsis / metabolism
  • Sepsis / physiopathology
  • Signal Transduction
  • TNF Receptor-Associated Factor 6 / metabolism
  • Ubiquitin Thiolesterase / metabolism*
  • Ubiquitin Thiolesterase / physiology

Substances

  • Beclin-1
  • Benzoxazines
  • Chromones
  • Cytokines
  • NF-kappa B
  • STAT1 Transcription Factor
  • TNF Receptor-Associated Factor 6
  • Usp14 protein, mouse
  • Ubiquitin Thiolesterase