Nitric oxide is an important regulator of heme oxygenase-1 expression in the lipopolysaccharide and interferon-γ-treated murine macrophage-like cell line J774.1/JA-4

Biol Pharm Bull. 2015;38(1):7-16. doi: 10.1248/bpb.b14-00405.


Heme oxygenase-1 (HO-1) catabolizes the degradation of heme into bilirubin, carbon monoxide, and iron ions. The HO-1 products provide antioxidant cytoprotection in addition to having potent antiinflammatory and immunomodulatory functions. HO-1 is induced by its substrate heme and environmental factors including oxidative and heat stresses. Although previous studies reported that lipopolysaccharide (LPS) induced the expression of both the HO-1 gene and its protein in macrophages, the major regulators of HO-1 expression remain unknown. To identify these regulators, we used two types of cell, the murine macrophage-like cell line J774.1/JA-4 and its LPS-resistant mutant, LPS1916. Based on a comparison of the results obtained with these cells, we found that nitric oxide (NO) was closely linked to the induction of HO-1. Real-time polymerase chain reaction (PCR) showed that the time course for inducible HO-1 mRNA by LPS or LPS+interferon (IFN)-γ was similar to that for inducible NO synthase (iNOS) mRNA. Furthermore, the expression of iNOS mRNA and protein increased earlier than that of HO-1 mRNA and protein. N-Nitro-L-arginine methyl ester, an NO synthase inhibitor, reduced both HO-1 expression and NO production in LPS+IFN-γ-treated JA-4 cells. Furthermore, NOC-12, an NO donor, significantly induced HO-1 expression not only in JA-4 but also in LPS1916 cells. Reactive oxygen species (ROS) scavengers, such as superoxide dismutase and catalase, did not affect HO-1 protein expression in LPS+IFN-γ-treated JA-4 cells. These results suggest that, among ROS, NO plays an important role in HO-1 induction in activated macrophages treated with LPS+IFN-γ.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Heme Oxygenase-1 / genetics
  • Heme Oxygenase-1 / metabolism*
  • Interferon-gamma / pharmacology
  • Lipopolysaccharides / pharmacology
  • Macrophages / metabolism*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Mice
  • Nitric Oxide / metabolism*
  • Nitric Oxide Synthase Type II / genetics
  • Nitric Oxide Synthase Type II / metabolism
  • RNA, Messenger / metabolism
  • Superoxides / metabolism


  • Lipopolysaccharides
  • Membrane Proteins
  • RNA, Messenger
  • Superoxides
  • Nitric Oxide
  • Interferon-gamma
  • Nitric Oxide Synthase Type II
  • Nos2 protein, mouse
  • Heme Oxygenase-1
  • Hmox1 protein, mouse