Your browser version may not work well with NCBI's Web applications. More information here...
Related Articles, Links
Click here to read Click here to read Click here to read
Glucocorticoids exert opposing effects on macrophage function dependent on their concentration.

Lim HY, Müller N, Herold MJ, van den Brandt J, Reichardt HM.

Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany.

Glucocorticoids (GCs) are involved in the modulation of macrophage function and thereby control the host's immune responses to pathogens. However, neither the role of hormone concentration nor the differential contribution of the glucocorticoid (GR) and the mineralocorticoid receptors (MR) to these activities are known. Here we show that low levels of corticosterone enhance NO production as well as mRNA expression of pro-inflammatory cytokines, chemokines and enzymes required for mediator synthesis. In contrast, at high corticosterone concentrations macrophage function was strongly repressed. Importantly, inactivation of the GR by lentiviral delivery of siRNAs abrogated both the immunostimulatory and the immunosuppressive GC actions whereas inactivation of the MR had no effect. Furthermore, removal of endogenous GCs by adrenalectomy in vivo induced a preactivated state in macrophages that could be modulated by corticosterone. We conclude that GCs exert distinct effects on macrophage function dependent on their concentration, and that they primarily act through the GR despite concomitant expression of the MR.

Publication Types:
PMID: 17451463 [PubMed - indexed for MEDLINE]

PMCID: PMC2265978