title: Estradiol effects on subcutaneous adipose tissue lipolysis in premenopausal women are adipose tissue depot specific and treatment dependent.
abstract: Estrogen has direct effects within adipose tissue and has been implicated in regional adiposity; however, the influence of estrogen on in vivo lipolysis is unclear. The purpose of this study was to investigate the effect of local 17β-estradiol (E(2)) on subcutaneous adipose tissue (SAT) lipolysis in premenopausal women. In vivo lipolysis (dialysate glycerol) was measured in 17 women (age 27.4 ± 2.0 yr, BMI 29.7 ± 0.5 kg/m(2)) via microdialysis of abdominal (AB) and gluteal (GL) SAT. Glycerol was measured at baseline and during acute interventions to increase lipolysis including local perfusion of isoproterenol (ISO, β-adrenergic agonist, 1.0 μmol/l), phentolamine (PHEN, α-adrenergic antagonist, 0.1 mmol/l), and submaximal exercise (60% Vo(2peak), 30 min); all with and without coperfusion of E(2) (500 nmol/l). E(2) coperfusion blunted the lipolytic response to ISO in AB (E(2) 196 ± 31%, control 258 ± 26%, P = 0.003) but not in GL (E(2) 113 ± 14%, control 111 ± 12%, P = 0.43) adipose tissue. At rest, perfusion of PHEN with ISO did not change dialysate glycerol. Submaximal exercise during ISO + PHEN increased dialysate glycerol in the AB (56 ± 9%) and GL (62 ± 12%) regions. Probes perfused with E(2) during exercise and ISO + PHEN had an increased lipolytic response in AB (90 ± 9%, P = 0.007) but a lower response in GL (35 ± 7%, P = 0.05) SAT compared with no-E(2) conditions. E(2) effects on lipolysis are region specific and may work through both adrenergic and adrenergic-independent mechanisms to potentiate and/or blunt SAT lipolysis in premenopausal women.
authors.affiliation: Human Performance Laboratory, College of Health and Human Performance and Brody School of Medicine, East Carolina University, Greenville, NC, USA. Kathleen.Gavin@UCDenver.edu
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Gavin
authors.forename: Elizabeth E
authors.initials: EE
authors.lastname: Cooper
authors.forename: Dustin K
authors.initials: DK
authors.lastname: Raymer
authors.forename: Robert C
authors.initials: RC
authors.lastname: Hickner
mesh_terms: D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000328:Adult; D004958:Estradiol / Q000494:pharmacology*; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology; D008066:Lipolysis / Q000187:drug effects* / Q000502:physiology; D050177:Overweight / Q000378:metabolism; D010646:Phentolamine / Q000494:pharmacology; D050151:Subcutaneous Fat / Q000187:drug effects* / Q000378:metabolism
chemical_list: D000317:Adrenergic alpha-Antagonists; D000318:Adrenergic beta-Agonists; D004958:Estradiol; D007545:Isoproterenol; D010646:Phentolamine
keywords: estrogen; exercise; lipolysis; microdialysis; regional adiposity