Enhancing Sirt1-mediated deacetylation of p62 with a self-assembling nanopeptide and resveratrol hydrogel to mitigate sepsis-induced inflammation.

BACKGROUND

Sepsis-induced inflammatory damage remains a significant clinical challenge with limited effective treatments. Elucidating the molecular mechanisms that regulate macrophage function may reveal key therapeutic targets to combat sepsis.

PURPOSE: This study aimed to investigate the role of Sirtuin 1 (Sirt1) in regulating mitochondrial autophagy and immunometabolic remodeling in macrophages to alleviate inflammation associated with septic shock.

STUDY

DESIGN

A controlled laboratory study was conducted using a murine sepsis model to elucidate the contribution of Sirt1 to macrophage function during sepsis-induced inflammation, employing both in vivo and in vitro approaches.

METHODS

Sepsis was induced in mice via cecal ligation and puncture (CLP). Peritoneal macrophages (PMs) from sham-operated and septic mice were analyzed using single-cell RNA sequencing (scRNA-seq). Differential gene expression, immunostaining, transmission electron microscopy (TEM), and metabolomics were performed to evaluate the roles of Sirt1 and Sqstm1 (p62) in modulating macrophage autophagy and inflammation.

RESULTS

Sirt1 expression was markedly reduced in PMs from septic mice. Sirt1-mediated deacetylation of p62 activated mitochondrial autophagy, suppressed lipopolysaccharide (LPS)-induced pro-inflammatory responses, and decreased mitochondrial reactive oxygen species (mtROS) production. Treatment with a self-assembling nanopeptide and resveratrol (Res) composite hydrogel improved survival rates and reduced tissue damage in septic mice. Integrated single-cell transcriptomics and metabolomics analyses demonstrated that Sirt1 modulated macrophage mitophagy and immunometabolic reprogramming, providing new insights into the molecular mechanisms of sepsis.

CONCLUSION

The self-assembling nanopeptide and Res hydrogel enhances Sirt1-mediated deacetylation of p62, promoting mitochondrial autophagy and immunometabolic remodeling, thereby mitigating sepsis-induced inflammation. This strategy represents a promising therapeutic approach for reducing inflammation-related damage in sepsis.