Glucocorticoid Receptor-β Is Downregulated by Vitamin D Treatment in Children with Low Vitamin D Levels but Not in Allergic Asthma

Abstract

Background: Vitamin D (VitD) enhances the anti-inflammatory effects of glucocorticoids (GC) in vitro. It was hypothesized that VitD3 (colecalciferol) treatment could have an impact on the expression of glucocorticoid receptors (GRs) in a group of children with low VitD levels, with or without asthma. Methods: Asthmatic children and healthy controls, all with low serum VitD levels (25-hydroxyvitamin D [25(OH)D] level <30 ng/mL) were recruited. VitD3 treatment at a dose of 300,000 IU was given orally. Blood samples were obtained at admission and 1 month after the treatment to examine serum 25(OH)D levels and the relative gene expression (RGE) of GR-α and -β in peripheral blood mononuclear cells. Results: Twenty-four children with asthma (Mage 11.1 ± 2.1 years) and 14 healthy controls (Mage 11.5 ± 1.7 years) were studied. The expression of GR-β was significantly higher in the control group at baseline compared with those with asthma (p = 0.006). With VitD3 treatment, there was a decrease in GRβ expression at...