title: Oxidative activity of 17β-hydroxysteroid dehydrogenase on testosterone in male abdominal adipose tissues and cellular localization of 17β-HSD type 2.
abstract: Testosterone can be converted into androstenedione (4-dione) by 17β-hydroxysteroid dehydrogenase (HSD) activity likely performed by 17β-HSD type 2. Our objective was to evaluate the rate of testosterone conversion to 4-dione as well as expression and localization of 17β-HSD type 2 in omental (OM) vs. subcutaneous (SC) adipose tissues of men. Formation of 4-dione from testosterone was significantly higher in homogenates (p ≤ 0.001) and explants (p ≤ 0.01) of OM than SC tissue. Microscopy analyses and biochemical assays in cell fractions localized the enzyme in the vasculature/endothelial cells of adipose tissues. Conversion of testosterone to 4-dione was weakly detected in most OM and/or SC preadipocyte cultures. Positive correlations were found between 17β-HSD type 2 activity in whole tissue and BMI or SC adipocyte diameter. We conclude that conversion of testosterone to 4-dione detected in abdominal adipose tissue is caused by 17β-HSD type 2 which is localized in the vasculature of the adipose compartment.
authors.affiliation: Endocrinology and Nephrology, CHU de Québec-Université Laval Medical Center, Québec, Canada.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Fouad Mansour
authors.affiliation: Endocrinology and Nephrology, CHU de Québec-Université Laval Medical Center, Québec, Canada.
authors.forename: Mélissa
authors.initials: M
authors.lastname: Pelletier
authors.affiliation: Endocrinology and Nephrology, CHU de Québec-Université Laval Medical Center, Québec, Canada; Quebec Cardiology and Pulmonology Institute, School of Nutrition, Université Laval, Québec, Canada.
authors.forename: Marie-Michèle
authors.initials: MM
authors.lastname: Boulet
authors.affiliation: Centre de recherche en organogénèse expérimentale de l'Université Laval /LOEX Division of Regenerative Medicine, CHU de Québec-Université Laval Medical Center, Québec, Canada; Department of Surgery, Université Laval, Québec, Canada.
authors.forename: Dominique
authors.initials: D
authors.lastname: Mayrand
authors.affiliation: Department of General Surgery, CHU de Québec-Université Laval Medical Center, Québec, Canada.
authors.forename: Gaétan
authors.initials: G
authors.lastname: Brochu
authors.affiliation: Quebec Cardiology and Pulmonology Institute, School of Nutrition, Université Laval, Québec, Canada.
authors.forename: Stefane
authors.initials: S
authors.lastname: Lebel
authors.affiliation: Endocrinology and Nephrology, CHU de Québec-Université Laval Medical Center, Québec, Canada.
authors.forename: Donald
authors.initials: D
authors.lastname: Poirier
authors.affiliation: Centre de recherche en organogénèse expérimentale de l'Université Laval /LOEX Division of Regenerative Medicine, CHU de Québec-Université Laval Medical Center, Québec, Canada; Department of Surgery, Université Laval, Québec, Canada.
authors.forename: Julie
authors.initials: J
authors.lastname: Fradette
authors.affiliation: Quebec Cardiology and Pulmonology Institute, School of Nutrition, Université Laval, Québec, Canada.
authors.forename: Katherine
authors.initials: K
authors.lastname: Cianflone
authors.affiliation: Endocrinology and Nephrology, CHU de Québec-Université Laval Medical Center, Québec, Canada.
authors.forename: Van
authors.initials: V
authors.lastname: Luu-The
authors.affiliation: Endocrinology and Nephrology, CHU de Québec-Université Laval Medical Center, Québec, Canada; Quebec Cardiology and Pulmonology Institute, School of Nutrition, Université Laval, Québec, Canada. Electronic address: andre.tchernof@crchudequebec.ulaval.ca.
authors.forename: André
authors.initials: A
authors.lastname: Tchernof
mesh_terms: D050153:Abdominal Fat / Q000166:cytology / Q000201:enzymology* / Q000378:metabolism; D000735:Androstenedione / Q000378:metabolism*; D015992:Body Mass Index; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000201:enzymology / Q000378:metabolism; D004960:Estradiol Dehydrogenases / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D050152:Intra-Abdominal Fat / Q000166:cytology / Q000201:enzymology / Q000378:metabolism; D008297:Male; D009765:Obesity / Q000201:enzymology / Q000378:metabolism; D009852:Omentum / Q000201:enzymology / Q000378:metabolism; D050507:Subcutaneous Fat, Abdominal / Q000166:cytology / Q000201:enzymology / Q000378:metabolism; D013739:Testosterone / Q000378:metabolism*
chemical_list: D013739:Testosterone; D000735:Androstenedione; D004960:Estradiol Dehydrogenases; C523763:HSD17B2 protein, human
keywords: 17β-HSD; 17β-HSD type 2; Adipose tissue; Testosterone