Dihydrotestosterone decreases tumor necrosis factor-alpha and lipopolysaccharide-induced inflammatory response in human endothelial cells.
BACKGROUND
An increasing body of evidence suggests that testosterone may exert beneficial effects on the development of atherosclerosis. It was suggested that testosterone may act after conversion into estradiol and activation of the estrogen receptors; however, a direct role of androgens on the vascular wall has been proposed.


OBJECTIVE
We investigated the effects of dihydrotestosterone on the proinflammatory response observed in human endothelial cells.


METHODS
Human endothelial cells isolated from umbilical cords were incubated with lipopolysaccharide or TNFalpha in the presence or absence of dihydrotestosterone (DHT). mRNA and cellular proteins were processed for gene expression studies, and transient transfection experiments were performed to investigate molecular mechanisms involved in the effects observed.


METHODS
These studies took place at the Department of Pharmacological Sciences, University of Milan, Milan, Italy.


RESULTS
Lipopolysaccharide and TNFalpha induced VCAM-1 and ICAM-1 mRNA and protein expression, as detected by real-time quantitative PCR, fluorescence-activated cell sorting, and confocal microscopy, but this effect was inhibited when cells were incubated with DHT. In addition, DHT inhibited mRNA expression of IL-6, MCP-1, CD40, TLR4, PAI-1, and Cox-2 and the release of cytokines and chemokines such as GRO, granulocyte-macrophage colony-stimulating factor, and TNF. The DHT effect was counteracted by bicalutamide, an antagonist of the androgen receptor. Furthermore, when cells were cotransfected with a Cox-2 promoter or a 3X-NF-kappaB luciferase reporter vector and a plasmid expressing the human androgen receptor, DHT treatment inhibited the increase of the luciferase activity observed with TNFalpha.


CONCLUSIONS
DHT could positively regulate endothelial function through the control of the inflammatory response mediated by nuclear factor-kappaB in endothelial cells.
Norata
Giuseppe Danilo
GD
Department of Pharmacological Sciences, University of Milan, Italy, Via Balzaretti 9, 20133 Milan, Italy. Danilo.Norata@unimi.it
Tibolla
Gianpaolo
G
Seccomandi
Paul Maria
PM
Poletti
Angelo
A
Catapano
Alberico Luigi
AL
D000726:Androgen Antagonists / Q000494:pharmacology; D059002:Androgen Receptor Antagonists; D000813:Anilides / Q000494:pharmacology; D045744:Cell Line, Tumor; D051546:Cyclooxygenase 2 / Q000096:biosynthesis / Q000235:genetics; D013196:Dihydrotestosterone / Q000494:pharmacology*; D004347:Drug Interactions; D019040:E-Selectin / Q000096:biosynthesis / Q000235:genetics; D042783:Endothelial Cells / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D006801:Humans; D015151:Immunoblotting; D007249:Inflammation / Q000188:drug therapy / Q000378:metabolism; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis / Q000235:genetics; D008070:Lipopolysaccharides / Q000494:pharmacology*; D016328:NF-kappa B / Q000378:metabolism; D009570:Nitriles; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D011944:Receptors, Androgen / Q000276:immunology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014105:Tosyl Compounds; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D019010:Vascular Cell Adhesion Molecule-1 / Q000096:biosynthesis / Q000235:genetics
D000726:Androgen Antagonists; D059002:Androgen Receptor Antagonists; D000813:Anilides; D019040:E-Selectin; D008070:Lipopolysaccharides; D016328:NF-kappa B; D009570:Nitriles; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D012333:RNA, Messenger; D011944:Receptors, Androgen; D014105:Tosyl Compounds; D014409:Tumor Necrosis Factor-alpha; D019010:Vascular Cell Adhesion Molecule-1; D013196:Dihydrotestosterone; D018799:Intercellular Adhesion Molecule-1; C053541:bicalutamide; D051546:Cyclooxygenase 2