Effect of dexamethasone on expression of glucocorticoid receptor in human monocyte cell line THP-1

Abstract

The effect of dexamethasone with different concentrations and different stimulating periods on the expression of glucocorticoid receptors (GRα, GRβ) protein was investigated in human monocyte cell line THP-1. The cultured human monocyte line THP-1 cells were stimulated by dexamethasone with different concentrations and different periods. The expression of GRα and GRβ protein was detected by Western blotting. The results showed that the expression of GRα and GRβ was detected in the THP-1 cells. The quantity of GRα expression was reduced by dexamethasone under the same concentration with the prolongation of the stimulating periods. The quantity of GRβ expression was increased by dexamethasone treatment in a time- and dose-dependent manner. It was concluded that dexamethasone stimulation time-dependently reduced the GRα expression in THP-1 cells. Dexamethasone stimulation time- and dose-dependently increased the GRβ expression in THP-1 cells. The expression of GRα and GRβ was regulated by glucocorticoid.

Keywords

dexamethasone / glucocorticoid / receptor / glucocorticoid resistance / Western blotting

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