p66(Shc) has a pivotal function in impaired liver regeneration in aged mice by a redox-dependent mechanism

Lab Invest. 2010 Dec;90(12):1718-26. doi: 10.1038/labinvest.2010.119. Epub 2010 Jun 21.

Abstract

Liver regeneration involves complicated processes and is affected by various patho-physiological conditions. This study was designed to examine the molecular mechanisms underlying the aging-associated impairment of liver regeneration. Male C57BL/6J mice were used as young and aged mice (<10 weeks and >20 months old, respectively). These mice were subjected to 70% partial hepatectomy (PH). Liver regeneration and liver injury/stresses were evaluated chronologically after PH. Post-hepatectomy liver regeneration was markedly impaired in aged mice. Though the extent of hepatocyte proliferation in the regenerating liver was similar in aged and young mice, cell growth was absent in aged mice. Oxidative stress (OS) was observed immediately after hepatectomy, followed by marked apoptosis in aged mice. Signaling molecules regarding cell proliferation (mitogen-activated protein kinase, STAT3, p46/52(Shc)) and anti-oxidation (catalase, superoxide dismutase, Ref-1, glutathione peroxidase) were expressed/activated after hepatectomy in livers of both aged and young mice. Akt was not activated in aged-mouse liver, but its expression was similar to that in young mice. p66(Shc), known as an age-/oxidant-associated protein, was strongly phosphorylated. By knocking down p66(Shc), the impairment of liver regeneration was normalized. OS immediately after hepatectomy induced subsequent liver injury (apoptosis), and deletion of p66(Shc) suppressed both OS and hepatocyte apoptosis in the regenerating liver of aged mice. Though we need additional data in other animal models to fully understand the mechanism, p66(Shc) may have a pivotal function in the impairment of liver regeneration in aged mice by triggering OS and subsequent apoptosis. This data may provide a clue to understanding the mechanism underlying the association between aging and the impairment of liver regeneration.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aging / physiology*
  • Animals
  • Apoptosis / physiology
  • Cell Proliferation
  • DNA-(Apurinic or Apyrimidinic Site) Lyase / metabolism
  • DNA-(Apurinic or Apyrimidinic Site) Lyase / physiology
  • Hepatectomy
  • Hepatocytes / metabolism
  • Hepatocytes / physiology
  • Liver / metabolism
  • Liver / physiology
  • Liver Regeneration / physiology*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Oxidation-Reduction
  • Oxidative Stress / physiology
  • Phosphorylation
  • Proto-Oncogene Proteins c-akt / metabolism
  • STAT3 Transcription Factor / metabolism
  • STAT3 Transcription Factor / physiology
  • Shc Signaling Adaptor Proteins / genetics
  • Shc Signaling Adaptor Proteins / metabolism*
  • Src Homology 2 Domain-Containing, Transforming Protein 1
  • Superoxide Dismutase / metabolism
  • Superoxide Dismutase / physiology

Substances

  • SHC4 protein, human
  • STAT3 Transcription Factor
  • Shc Signaling Adaptor Proteins
  • Shc1 protein, mouse
  • Src Homology 2 Domain-Containing, Transforming Protein 1
  • Superoxide Dismutase
  • Proto-Oncogene Proteins c-akt
  • DNA-(Apurinic or Apyrimidinic Site) Lyase