Haemolytic anaemia and alterations in hepatic iron metabolism in aged mice lacking Cu,Zn-superoxide dismutase

Biochem J. 2009 May 27;420(3):383-90. doi: 10.1042/BJ20082137.

Abstract

The continuous recycling of haem iron following phagocytosis and catabolism of senescent and damaged red blood cells by macrophages is a crucial process in the maintenance of systemic iron homoeostasis. However, little is known about macrophage iron handling in haemolytic states resulting from a deficiency in antioxidant defences. Our observations indicate that the recently described chronic, but moderate regenerative, haemolytic anaemia of aged SOD1 (superoxide dismutase 1)-knockout mice is associated with red blood cell modifications and sensitivity to both intra- and extra-vascular haemolysis. In the present study, we have characterized the molecular pathways of iron turnover in the liver of Sod1-deficient mice. Despite iron accumulation in liver macrophages, namely Kupffer cells, we did not measure any significant change in non-haem liver iron. Interestingly, in Kupffer cells, expression of the rate-limiting enzyme in haem degradation, haem oxygenase-1, and expression of the iron exporter ferroportin were both up-regulated, whereas the hepcidin mRNA level in the liver was decreased in Sod1-/- mice. These results suggest that concerted changes in the hepatic expression of iron- and haem-related genes in response to haemolytic anaemia in Sod1-/- mice act to reduce toxic iron accumulation in the liver and respond to the needs of erythropoiesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aging
  • Anemia, Hemolytic / blood
  • Anemia, Hemolytic / metabolism*
  • Anemia, Hemolytic / pathology
  • Animals
  • Antimicrobial Cationic Peptides / genetics
  • Antimicrobial Cationic Peptides / metabolism
  • Blotting, Western
  • Cation Transport Proteins / genetics
  • Cation Transport Proteins / metabolism
  • Erythrocytes / metabolism
  • Erythrocytes / pathology
  • Female
  • Flow Cytometry
  • Fluorescent Antibody Technique
  • Heme / metabolism
  • Heme Oxygenase-1 / genetics
  • Heme Oxygenase-1 / metabolism
  • Hemoglobins / metabolism
  • Hemolysis
  • Hepcidins
  • Iron / blood
  • Iron / metabolism*
  • Liver / metabolism*
  • Liver / pathology
  • Male
  • Mice
  • Mice, Inbred Strains
  • Mice, Knockout
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Superoxide Dismutase / deficiency*
  • Superoxide Dismutase / genetics

Substances

  • Antimicrobial Cationic Peptides
  • Cation Transport Proteins
  • Hamp protein, mouse
  • Hemoglobins
  • Hepcidins
  • RNA, Messenger
  • metal transporting protein 1
  • Heme
  • Iron
  • Heme Oxygenase-1
  • Superoxide Dismutase