title: Associations between Bone Mineral Characteristics and Serum Levels of Ghrelin and Peptide YY in Overweight Adolescent Boys.
abstract: OBJECTIVE
  The role of ghrelin and peptide YY (PYY) in bone mineralization is not fully known. The aim of this study was to determine whether acylated and des-acyl ghrelin and PYY in addition to leptin are related to bone mineral density (BMD) in adolescent overweight boys (OWB) and normal-weight boys (NWB).
  
  
  METHODS
  Fifty- five OWB (BMI >85th percentile) and 154 NWB (BMI <85th percentile) aged 12-16 years participated in this study. Fasting serum acylated and des-acyl ghrelin, PYY, leptin, testosterone levels, total body (TB) and lumbar spine (LS) bone mineral content (BMC), and BMD were measured. TB BMC for height and TB and LS bone mineral apparent density (BMAD) were calculated.
  
  
  RESULTS
  No differences were seen in acylated and des-acyl ghrelin or PYY levels, while the leptin levels were significantly higher in the OWB compared to the NWB. In the OWB, TB BMAD was positively correlated with acylated ghrelin and leptin, and TB BMC for height was positively correlated with PYY. In the OWB, the variability of TB BMD was determined by TB fat-free mass and des-acyl ghrelin, whereas the variability of TB BMAD was determined by leptin.
  
  
  CONCLUSIONS
  Des-acyl ghrelin and PYY are involved in the bone mineralization process in puberty, and the impact can vary between normal and overweight subjects.
authors.affiliation: Faculty of Exercise and Sport Sciences, University of Tartu, Tartu, Estonia.
authors.forename: Liina
authors.initials: L
authors.lastname: Remmel
authors.forename: Vallo
authors.initials: V
authors.lastname: Tillmann
authors.forename: Jarek
authors.initials: J
authors.lastname: Mäestu
authors.forename: Priit
authors.initials: P
authors.lastname: Purge
authors.forename: Meeli
authors.initials: M
authors.lastname: Saar
authors.forename: Evelin
authors.initials: E
authors.lastname: Lätt
authors.forename: Katre
authors.initials: K
authors.lastname: Maasalu
authors.forename: Toivo
authors.initials: T
authors.lastname: Jürimäe
authors.forename: Jaak
authors.initials: J
authors.lastname: Jürimäe
mesh_terms: D000293:Adolescent; D015519:Bone Density; D054439:Ghrelin / Q000097:blood*; D006801:Humans; D008297:Male; D050177:Overweight / Q000097:blood*; D019894:Peptide YY / Q000097:blood*; D011627:Puberty / Q000097:blood*
chemical_list: D054439:Ghrelin; D019894:Peptide YY