New insights into the anti-inflammatory mechanisms of glucocorticoids: an emerging role for glucocorticoid-receptor-mediated transactivation

Endocrinology. 2013 Mar;154(3):993-1007. doi: 10.1210/en.2012-2045. Epub 2013 Feb 5.

Abstract

Glucocorticoids are anti-inflammatory drugs that are widely used for the treatment of numerous (autoimmune) inflammatory diseases. They exert their actions by binding to the glucocorticoid receptor (GR), a member of the nuclear receptor family of transcription factors. Upon ligand binding, the GR translocates to the nucleus, where it acts either as a homodimeric transcription factor that binds glucocorticoid response elements (GREs) in promoter regions of glucocorticoid (GC)-inducible genes, or as a monomeric protein that cooperates with other transcription factors to affect transcription. For decades, it has generally been believed that the undesirable side effects of GC therapy are induced by dimer-mediated transactivation, whereas its beneficial anti-inflammatory effects are mainly due to the monomer-mediated transrepressive actions of GR. Therefore, current research is focused on the development of dissociated compounds that exert only the GR monomer-dependent actions. However, many recent reports undermine this dogma by clearly showing that GR dimer-dependent transactivation is essential in the anti-inflammatory activities of GR. Many of these studies used GR(dim/dim) mutant mice, which show reduced GR dimerization and hence cannot control inflammation in several disease models. Here, we review the importance of GR dimers in the anti-inflammatory actions of GCs/GR, and hence we question the central dogma. We summarize the contribution of various GR dimer-inducible anti-inflammatory genes and question the use of selective GR agonists as therapeutic agents.

Publication types

  • Review

MeSH terms

  • Animals
  • Annexin A1 / genetics
  • Annexin A1 / metabolism
  • Anti-Inflammatory Agents / metabolism
  • Anti-Inflammatory Agents / pharmacology*
  • Glucocorticoids / metabolism
  • Glucocorticoids / pharmacology*
  • Humans
  • Mice
  • Mice, Mutant Strains
  • Models, Biological
  • Protein Multimerization
  • Receptors, Glucocorticoid / chemistry
  • Receptors, Glucocorticoid / genetics
  • Receptors, Glucocorticoid / metabolism*
  • Response Elements
  • Signal Transduction
  • Transcriptional Activation* / drug effects

Substances

  • Annexin A1
  • Anti-Inflammatory Agents
  • Glucocorticoids
  • Receptors, Glucocorticoid