Short-term Low-Dose mTORC1 Inhibition in Aged Rats Counter-Regulates Age-Related Gene Changes and Blocks Age-Related Kidney Pathology

J Gerontol A Biol Sci Med Sci. 2018 Jun 14;73(7):845-852. doi: 10.1093/gerona/glx249.

Abstract

Rapalogs, inhibitors of mTORC1 (mammalian target of rapamycin complex 1), increase life span and delay age-related phenotypes in many species. However, the molecular mechanisms have not been fully elucidated. We determined gene expression changes comparing 6- and 24-month-old rats in the kidney, liver, and skeletal muscle, and asked which of these changes were counter-regulated by a clinically-translatable (short-term and low-concentration) treatment, with a rapalog (RAD001). Surprisingly, RAD001 had a more pronounced effect on the kidney under this regimen in comparison to the liver or skeletal muscle. Histologic evaluation of kidneys revealed that the severity of chronic progressive nephropathy lesions was lower in kidneys from 24-month-old rats treated with RAD001 compared with vehicle. In addition to other gene expression changes, c-Myc, which has been shown to regulate aging, was induced by aging in the kidney and counter-regulated by RAD001. RAD001 caused a decrease in c-Myc protein, which could be rescued by a proteasome inhibitor. These findings point to settings for use of mTORC1 inhibitors to treat age-related disorders, and highlight c-Myc regulation as one of the potential mechanisms by which mTORC1 inhibition is perturbing age-related phenotypes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aging / drug effects*
  • Aging / genetics
  • Aging / pathology
  • Animals
  • Drug Administration Schedule
  • Enzyme Inhibitors / administration & dosage
  • Everolimus / administration & dosage*
  • Gene Expression / drug effects
  • Gene Expression Profiling
  • HEK293 Cells
  • Humans
  • Kidney / drug effects*
  • Kidney / metabolism
  • Kidney / pathology
  • Liver / drug effects
  • Liver / metabolism
  • Longevity / drug effects
  • Longevity / genetics
  • Male
  • Mechanistic Target of Rapamycin Complex 1 / antagonists & inhibitors*
  • Muscle, Skeletal / drug effects
  • Muscle, Skeletal / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Renal Insufficiency, Chronic / drug therapy
  • Renal Insufficiency, Chronic / pathology
  • TOR Serine-Threonine Kinases / antagonists & inhibitors*

Substances

  • Enzyme Inhibitors
  • Everolimus
  • mTOR protein, rat
  • Mechanistic Target of Rapamycin Complex 1
  • TOR Serine-Threonine Kinases