Age modulates liver responses to asparaginase-induced amino acid stress in mice

J Biol Chem. 2019 Sep 20;294(38):13864-13875. doi: 10.1074/jbc.RA119.009864. Epub 2019 Aug 14.

Abstract

Asparaginase is an amino acid-depleting agent used to treat blood cancers. Metabolic complications due to asparaginase affect liver function in humans. To examine how the liver response to asparaginase changes during maturity to adulthood, here we treated juvenile (2-week), young adult (8-week), and mature adult (16-week) mice with drug or excipient for 1 week and conducted RNA-Seq and functional analyses. Asparaginase reduced body growth and liver mass in juveniles but not in the adult animals. Unbiased exploration of the effect of asparaginase on the liver transcriptome revealed that the integrated stress response (ISR) was the only molecular signature shared across the ages, corroborating similar eukaryotic initiation factor 2 phosphorylation responses to asparaginase at all ages. Juvenile livers exhibited steatosis and iron accumulation following asparaginase exposure along with a hepatic gene signature indicating that asparaginase uniquely affects lipid, cholesterol, and iron metabolism in juvenile mice. In contrast, asparaginase-treated adult mice displayed greater variability in liver function, which correlated with an acute-phase inflammatory response gene signature. Asparaginase-exposed adults also had a serine/glycine/one-carbon metabolism gene signature in liver that corresponded with reduced circulating glycine and serine levels. These results establish the ISR as a conserved response to asparaginase-mediated amino acid deprivation and provide new insights into the relationship between the liver transcriptome and hepatic function upon asparaginase exposure.

Keywords: age-dependent response; amino acid; asparaginase; development; eukaryotic initiation factor 2 (eIF2); hepatic metabolism; integrated stress response; integrated stress response (ISR); mRNA; triglyceride.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Age Factors
  • Amino Acids / metabolism
  • Animals
  • Asparaginase / adverse effects*
  • Asparaginase / metabolism*
  • Asparaginase / physiology
  • Eukaryotic Initiation Factor-2 / metabolism
  • Fatty Liver / metabolism
  • Female
  • Liver / metabolism*
  • Liver / pathology
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Phosphorylation
  • Protein Serine-Threonine Kinases / metabolism
  • Stress, Physiological / drug effects
  • Transcriptome / drug effects
  • Transcriptome / genetics

Substances

  • Amino Acids
  • Eukaryotic Initiation Factor-2
  • Protein Serine-Threonine Kinases
  • Asparaginase