title: Prepubertal healthy children's urinary androstenediol predicts diaphyseal bone strength in late puberty.
abstract: BACKGROUND
  During the physiological process of adrenarche, the adrenal glands of healthy children secrete increasing amounts of weak androgenic steroids partly metabolized to potent sex steroids.
  
  
  OBJECTIVE
  The aim of the study was to examine whether adrenal androgen metabolite excretion rates before the onset of puberty may be prospectively associated with late-pubertal diaphyseal bone strength.
  
  
  METHODS
  We conducted the study in an auxological and metabolic child nutrition research facility.
  
  
  METHODS
  The sample included 45 healthy adolescents who underwent proximal forearm bone and muscle area measurements by peripheral quantitative computed tomography at the age of 16 yr (SD 1.5) and who had collected a 24-h urine sample 8 yr earlier, allowing to quantify the prepubertal urine metabolome. Prepubertal hormonal predictors quantified by gas chromatography-mass spectrometry were: dehydroepiandrosterone, its 16-hydroxylated downstream metabolites, 5-androstene-3beta,17beta-diol (androstenediol), sums of total androgen and glucocorticoid metabolites, cortisol, and 6beta-hydroxycortisol.
  
  
  RESULTS
  Proximal forearm radius was measured.
  
  
  RESULTS
  Of all prepubertal hormones analyzed, only sex- and age-specific androstenediol levels significantly predicted pubertal stage-, height-, and muscularity-adjusted diaphyseal bone modeling (periosteal circumference, beta = 0.67, P = 0.002; cortical area, beta = 2.15, P = 0.02), bone mineral content (beta = 2.2; P = 0.04), and polar strength strain index (beta = 12.2; P = 0.002). Androstenediol explained 5-10% of the late-pubertal diaphyseal radius variability.
  
  
  CONCLUSIONS
  Our prospective profiling of urinary steroid metabolites in 24-h urine samples collected before puberty suggests that androstenediol is an early predictor of the diaphyseal bone strength in late puberty. This predominantly peripheral conversion product of adrenarchal dehydroepiandrosterone by 17beta-hydroxysteroid dehydrogenase may hence be involved in a sustained improvement of radial bone accretion during growth.
authors.affiliation: Department of Nutrition and Health, Research Institute of Child Nutrition, Forschungsinstitut für Kinderernährung, Heinstück 11, 44225 Dortmund, Germany. remer@fke-do.de
authors.forename: Thomas
authors.initials: T
authors.lastname: Remer
authors.forename: Friedrich
authors.initials: F
authors.lastname: Manz
authors.forename: Michaela F
authors.initials: MF
authors.lastname: Hartmann
authors.forename: Eckhard
authors.initials: E
authors.lastname: Schoenau
authors.forename: Stefan A
authors.initials: SA
authors.lastname: Wudy
mesh_terms: D000293:Adolescent; D041923:Adolescent Development / Q000502:physiology; D000734:Androstenediols / Q000652:urine*; D001842:Bone and Bones / Q000502:physiology*; D002648:Child; D019245:Compressive Strength / Q000502:physiology; D018483:Diaphyses / Q000502:physiology*; D005260:Female; D005544:Forecasting; D006262:Health; D006801:Humans; D008297:Male; D055442:Metabolome / Q000502:physiology; D011627:Puberty / Q000502:physiology* / Q000652:urine; D011884:Radius / Q000502:physiology
chemical_list: D000734:Androstenediols