title: Influence of sex hormones on adiponectin expression in human adipocytes.
abstract: Adiponectin is an adipokine with profound antidiabetic and antiatherogenic effects. Circulating adiponectin concentrations are higher in women than in men. In order to study the molecular aspects of this sex-specific dimorphism, we examined the expression of adiponectin in human fat cells under the influence of sex hormones, using SGBS cells as an in vitro model. Androgen and estradiol receptor 1 and 2 (AR, ESR1, ESR2) mRNA expression increased dramatically during adipogenic differentiation. Stimulation with human male and female serum led to a downregulation of adiponectin expression, with male serum exerting significantly stronger inhibitory properties than female serum (p<0.05). Increasing concentrations of testosterone or estradiol influenced neither adiponectin mRNA expression and secretion nor intracellular protein expression of high-, middle-, and low-molecular-weight (HMW, MMW, LMW) adiponectin multimers. These data have been verified in in vitro-differentiated primary human adipocytes. We conclude that although human adipocytes express AR, ESR1, and ESR2 and respond to testosterone treatment with a decrease in leptin expression, expression and secretion of adiponectin is unaffected by sex steroids. We hypothesize, therefore, the existence of a serum factor that is differently regulated by sex steroids and subsequently causes the sex dimorphism in circulating adiponectin levels.
authors.affiliation: Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, University of Ulm, Ulm, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Horenburg
authors.forename: P
authors.initials: P
authors.lastname: Fischer-Posovszky
authors.forename: K-M
authors.initials: KM
authors.lastname: Debatin
authors.forename: M
authors.initials: M
authors.lastname: Wabitsch
mesh_terms: D017667:Adipocytes / Q000737:chemistry / Q000378:metabolism*; D052242:Adiponectin / Q000032:analysis / Q000235:genetics* / Q000378:metabolism; D001769:Blood; D002454:Cell Differentiation; D002460:Cell Line; D015536:Down-Regulation; D004958:Estradiol / Q000494:pharmacology; D047628:Estrogen Receptor alpha / Q000235:genetics; D047629:Estrogen Receptor beta / Q000235:genetics; D005260:Female; D015870:Gene Expression / Q000187:drug effects*; D012739:Gonadal Steroid Hormones / Q000494:pharmacology*; D006801:Humans; D008297:Male; D012333:RNA, Messenger / Q000032:analysis; D011944:Receptors, Androgen / Q000235:genetics; D012727:Sex Characteristics; D013739:Testosterone / Q000494:pharmacology
chemical_list: D052242:Adiponectin; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D012739:Gonadal Steroid Hormones; D012333:RNA, Messenger; D011944:Receptors, Androgen; D013739:Testosterone; D004958:Estradiol