title: Independent effects of testosterone on lipid oxidation and VLDL-TG production: a randomized, double-blind, placebo-controlled, crossover study.
abstract: Low testosterone (T) levels in men have been shown to predict development of the metabolic syndrome, but the effects of T on lipid metabolism are incompletely understood. In a randomized, double-blind, placebo-controlled, crossover study, 12 healthy, young males received gonadotropin-releasing hormone agonist treatment 1 month prior to 3 of 4 trial days to induce castrate levels of T. On trial days, T gel was applied to the body containing either high or low physiological T dose or placebo. On the 4th trial day, participants constituted their own eugonadal controls. Each study comprised a 5-h basal period and a 3-h hyperinsulinemic-euglycemic clamp. Short-term hypogonadism did not affect VLDL triglyceride (TG) secretion, nor did it affect VLDL-TG concentrations. It was, however, characterized by lower total lipid oxidation. In addition, acute rescue with high physiological T increased VLDL-TG secretion during both basal and clamp conditions. These data show that T can act through fast nongenomic pathways in the liver. In addition, the early hypogonadal state is characterized by decreased total lipid oxidation, but whether these changes represent early hypogonadal metabolic dysfunction warrants further investigations. T is not a major determinant of resting VLDL-TG kinetics in men.
authors.affiliation: Department of Endocrinology and Internal Medicine and the Medical Research Laboratories, Clinical Institute, Aarhus University Hospital, Aarhus, Denmark. christian.host@ki.au.dk
authors.forename: Christian
authors.initials: C
authors.lastname: Høst
authors.forename: Lars C
authors.initials: LC
authors.lastname: Gormsen
authors.forename: Britt
authors.initials: B
authors.lastname: Christensen
authors.forename: Niels
authors.initials: N
authors.lastname: Jessen
authors.forename: David M
authors.initials: DM
authors.lastname: Hougaard
authors.forename: Jens S
authors.initials: JS
authors.lastname: Christiansen
authors.forename: Steen B
authors.initials: SB
authors.lastname: Pedersen
authors.forename: Michael D
authors.initials: MD
authors.lastname: Jensen
authors.forename: Søren
authors.initials: S
authors.lastname: Nielsen
authors.forename: Claus H
authors.initials: CH
authors.lastname: Gravholt
mesh_terms: D000279:Administration, Cutaneous; D000328:Adult; D000728:Androgens / Q000008:administration & dosage / Q000172:deficiency / Q000378:metabolism* / Q000627:therapeutic use; D002250:Carbon Radioisotopes; D018592:Cross-Over Studies; D003692:Delayed-Action Preparations; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D007987:Gonadotropin-Releasing Hormone / Q000037:antagonists & inhibitors; D020249:Hormone Replacement Therapy; D006801:Humans; D007006:Hypogonadism / Q000097:blood / Q000139:chemically induced / Q000188:drug therapy / Q000378:metabolism; D007700:Kinetics; D016729:Leuprolide / Q000008:administration & dosage / Q000633:toxicity; D008066:Lipolysis / Q000187:drug effects; D008079:Lipoproteins, VLDL / Q000096:biosynthesis* / Q000097:blood / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D013739:Testosterone / Q000008:administration & dosage / Q000172:deficiency / Q000378:metabolism* / Q000627:therapeutic use; D014280:Triglycerides / Q000096:biosynthesis* / Q000097:blood; D014304:Triolein / Q000378:metabolism; D055815:Young Adult
chemical_list: D000728:Androgens; D002250:Carbon Radioisotopes; D003692:Delayed-Action Preparations; D008079:Lipoproteins, VLDL; D014280:Triglycerides; C493311:luprolide acetate gel depot; D014304:Triolein; D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; D016729:Leuprolide