17β-estradiol enhances vascular endothelial growth factor production and dihydrotestosterone antagonizes the enhancement via the regulation of adenylate cyclase in differentiated THP-1 cells

Abstract

We studied the in vitro effects of sex hormones on vascular endothelial growth factor (VEGF) production in differentiated THP-1 monocytic cells. Phorbol-12-myristate-13-acetate differentiated THP-1 into macrophage-like cells. 17β-estradiol (10-9 M) increased VEGF secretion of controls 3.1-fold in differentiated THP-1 and this effect of 17β-estradiol was antagonized by dihydrotestosterone, although dihydrotestosterone alone did not alter VEGF secretion. 17β-estradiol increased steady-state mRNA level of VEGF and the increase was counteracted by dihydrotestosterone in differentiated THP-1, although dihydrotestosterone alone did not alter the VEGF mRNA level. Progesterone did not affect the constitutive and 17β-estradiol-induced VEGF secretion and mRNA level. Transient transfection revealed that 17β-estradiol enhanced chloramphenicol acetyl transferase expression driven by VEGF promoter and the enhancement was antagonized by dihydrotestosterone. Adenylate cyclase inhibitor suppressed 17β-estradiol-induced enhancement of VEGF secretion, mRNA level, and promoter activity, whereas dihydrotestosterone-induced suppression on the effects of 17β-estradiol was counteracted by 3′,5′-adenosine cyclic monophosphate (cAMP) analog. 17β-estradiol increased intracellular cAMP level by activating adenylate cyclase, while dihydrotestosterone reduced the basal and 17β-estradiol-increased cAMP level by inhibiting adenylate cyclase. Transfection with 5′-deleted VEGF promoters demonstrated that the region between -88 and -66 bp may be involved in the transcriptional regulation by each hormone. The mutation within activator protein-2 element in this region abrogated the transcriptional stimulation and repression by the respective hormones. 17β-estradiol activated transcription from activator protein-2-responsive reporter plasmid while dihydrotestosterone antagonized the effect of 17β-estradiol. These results suggest that 17β-estradiol enhances VEGF production while dihydrotestosterone antagonizes the effect of 17β-estradiol via up- or downregulation of adenylate cyclase in differentiated THP-1.