Ferritin and the response to oxidative stress

Biochem J. 2001 Jul 1;357(Pt 1):241-7. doi: 10.1042/0264-6021:3570241.


Iron is required for normal cell growth and proliferation. However, excess iron is potentially harmful, as it can catalyse the formation of toxic reactive oxygen species (ROS) via Fenton chemistry. For this reason, cells have evolved highly regulated mechanisms for controlling intracellular iron levels. Chief among these is the sequestration of iron in ferritin. Ferritin is a 24 subunit protein composed of two subunit types, termed H and L. The ferritin H subunit has a potent ferroxidase activity that catalyses the oxidation of ferrous iron, whereas ferritin L plays a role in iron nucleation and protein stability. In the present study we report that increased synthesis of both subunits of ferritin occurs in HeLa cells exposed to oxidative stress. An increase in the activity of iron responsive element binding proteins in response to oxidative stress was also observed. However, this activation was transient, allowing ferritin protein induction to subsequently proceed. To assess whether ferritin induction reduced the accumulation of ROS, and to test the relative contribution of ferritin H and L subunits in this process, we prepared stable transfectants that overexpressed either ferritin H or ferritin L cDNA under control of a tetracycline-responsive promoter. We observed that overexpression of either ferritin H or ferritin L reduced the accumulation of ROS in response to oxidant challenge.

Publication types

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

MeSH terms

  • Cytosol / metabolism
  • Doxycycline / pharmacology
  • Electroporation
  • Ferritins / chemistry
  • Ferritins / genetics*
  • Gene Expression Regulation / drug effects
  • Gene Expression Regulation / physiology*
  • HeLa Cells
  • Humans
  • Hydrogen Peroxide / pharmacology*
  • Iron-Regulatory Proteins
  • Iron-Sulfur Proteins / genetics
  • Iron-Sulfur Proteins / metabolism
  • Kinetics
  • Oxidative Stress / physiology*
  • Plasmids
  • Promoter Regions, Genetic / drug effects
  • Protein Subunits
  • RNA-Binding Proteins / genetics
  • RNA-Binding Proteins / metabolism
  • Reactive Oxygen Species / metabolism
  • Tetracycline / pharmacology
  • Transcription, Genetic / physiology*
  • Transfection


  • Iron-Regulatory Proteins
  • Iron-Sulfur Proteins
  • Protein Subunits
  • RNA-Binding Proteins
  • Reactive Oxygen Species
  • Ferritins
  • Hydrogen Peroxide
  • Tetracycline
  • Doxycycline