Inhibition of S6K lowers age-related inflammation and increases lifespan through the endolysosomal system

Nat Aging. 2024 Apr;4(4):491-509. doi: 10.1038/s43587-024-00578-3. Epub 2024 Feb 27.

Abstract

Suppression of target of rapamycin complex 1 (TORC1) by rapamycin ameliorates aging in diverse species. S6 kinase (S6K) is an essential mediator, but the mechanisms involved are unclear. Here we show that activation of S6K specifically in Drosophila fat-body blocked extension of lifespan by rapamycin, induced accumulation of multilamellar lysosomes and blocked age-associated hyperactivation of the NF-κB-like immune deficiency (IMD) pathway, indicative of reduced inflammaging. Syntaxin 13 mediated the effects of TORC1-S6K signaling on lysosome morphology and inflammaging, suggesting they may be linked. Inflammaging depended on the IMD receptor regulatory isoform PGRP-LC, and repression of the IMD pathway from midlife extended lifespan. Age-related inflammaging was higher in females than in males and was not lowered in males by rapamycin treatment or lowered S6K. Rapamycin treatment also elevated Syntaxin 12/13 levels in mouse liver and prevented age-related increase in noncanonical NF-κB signaling, suggesting that the effect of TORC1 on inflammaging is conserved from flies to mammals.

MeSH terms

  • Animals
  • Drosophila
  • Female
  • Inflammation / drug therapy
  • Longevity*
  • Male
  • Mechanistic Target of Rapamycin Complex 1 / metabolism
  • Mice
  • NF-kappa B* / genetics
  • Ribosomal Protein S6 Kinases / metabolism
  • Sirolimus / pharmacology

Substances

  • Mechanistic Target of Rapamycin Complex 1
  • NF-kappa B
  • Ribosomal Protein S6 Kinases
  • Sirolimus
  • S6k protein, Drosophila