title: Hyperghrelinemia is a common feature of Prader-Willi syndrome and pituitary stalk interruption: a pathophysiological hypothesis.
abstract: BACKGROUND
  Elevated plasma ghrelin levels have recently been reported in adults and children with Prader-Willi syndrome (PWS). The aim of the study is to investigate the relationship between obesity, growth hormone (GH) deficiency (GHD) and ghrelinemia in PWS and to examine whether hyperghrelinemia is specific to PWS.
  
  
  METHODS
  We measured fasting ghrelinemia in children with PWS, idiopathic GHD (iGHD), obese children, controls and in 6 children presenting another congenital syndrome associated with GHD: pituitary stalk interruption (PSI).
  
  
  RESULTS
  Children with PWS exhibited significantly higher ghrelin levels (995 pg/ml (801/1,099, median 1st/3rd quartile)) than iGHD (517 pg/ml (392/775)), obese (396 pg/ml (145/610)) and control (605 ng/ml (413/753)) children. Similar to PWS hyperghrelinemia was found in PSI children (1,029 pg/ml (705/1,151)), and was not modified by GH treatment.
  
  
  CONCLUSIONS
  We conclude that hyperghrelinemia in PWS and PSI is not related to GH secretion. We hypothesize that a major site of ghrelin action is at the hypothalamic level and that a 'ghrelin resistance' syndrome may be present in these patients, primarily due to a hypothalamic defect. Combined alterations such as impaired serotonin receptor regulation associated with abnormal ghrelin responsiveness are probably responsible for obesity in PWS.
authors.affiliation: Division of Endocrinology, Bone Diseases, Genetics and Gynecology, Children's Hospital, INSERM U563 (CPTP), IFR 30, Hôpital Purpan, Toulouse, France. crc@chu-toulouse.fr
authors.forename: Maithé
authors.initials: M
authors.lastname: Tauber
authors.forename: Françoise
authors.initials: F
authors.lastname: Conte Auriol
authors.forename: Pierre
authors.initials: P
authors.lastname: Moulin
authors.forename: Catherine
authors.initials: C
authors.lastname: Molinas
authors.forename: Véronique
authors.initials: V
authors.lastname: Delagnes
authors.forename: Jean Pierre
authors.initials: JP
authors.lastname: Salles
mesh_terms: D000375:Aging / Q000097:blood; D015992:Body Mass Index; D016022:Case-Control Studies; D002648:Child; D000013:Congenital Abnormalities / Q000097:blood; D005260:Female; D054439:Ghrelin; D013006:Growth Hormone / Q000627:therapeutic use; D019382:Human Growth Hormone / Q000172:deficiency / Q000378:metabolism; D006801:Humans; D008297:Male; D008954:Models, Biological; D009765:Obesity / Q000097:blood; D036361:Peptide Hormones / Q000097:blood*; D010902:Pituitary Gland / Q000002:abnormalities*; D011218:Prader-Willi Syndrome / Q000097:blood* / Q000188:drug therapy / Q000378:metabolism; D043202:Steroid Metabolism, Inborn Errors / Q000097:blood
chemical_list: D054439:Ghrelin; D036361:Peptide Hormones; D019382:Human Growth Hormone; D013006:Growth Hormone