title: Detection of obestatin in seminal plasma and its relationship with ghrelin and semen parameters.
abstract: OBJECTIVE
  To investigate the occurrence of ghrelin and obestatin in human semen.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  University, center for research and therapy of male infertility.
  
  
  METHODS
  112 consecutively selected men.
  
  
  METHODS
  Family history, clinical and physical examination, radioimmunoassay for ghrelin and obestatin determinations, semen analysis, annexinV/propidium iodide assay.
  
  
  METHODS
  Ghrelin and obestatin detected in the semen and relationships with semen parameters and conditions influencing semen quality (smoking, varicocele, ex varicocele, leukocytospermia).
  
  
  RESULTS
  The levels of both peptides in semen were higher versus serum. Linear correlations between ghrelin and obestatin levels in serum and in semen were observed. Serum ghrelin levels were negatively correlated with the men's ages. Semen obestatin levels were positively correlated with sperm concentration and motility. Obestatin levels were decreased in the semen of smokers and in the presence of leukocytospermia.
  
  
  CONCLUSIONS
  This is the first study on the presence of obestatin in human semen and its relationship with sperm concentration and motility, suggesting a possible role of the peptide in controlling cell proliferation and survival. Further investigations are required to explore the exact role of obestatin and ghrelin in human semen.
authors.affiliation: Department of Biomedical Sciences, Applied Biology Section, Interdepartmental Centre for Research and Therapy of Male Infertility, University of Siena, Siena, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Moretti
authors.forename: Giulia
authors.initials: G
authors.lastname: Collodel
authors.forename: Francesca
authors.initials: F
authors.lastname: Iacoponi
authors.forename: Michela
authors.initials: M
authors.lastname: Geminiani
authors.forename: Nicola Antonio
authors.initials: NA
authors.lastname: Pascarelli
authors.forename: Stella
authors.initials: S
authors.lastname: Campagna
authors.forename: Beatrice
authors.initials: B
authors.lastname: Franci
authors.forename: Natale
authors.initials: N
authors.lastname: Figura
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000032:analysis; D016009:Chi-Square Distribution; D054439:Ghrelin / Q000032:analysis* / Q000097:blood; D006801:Humans; D007248:Infertility, Male / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D007558:Italy; D008297:Male; D011446:Prospective Studies; D011863:Radioimmunoassay; D018570:Risk Assessment; D012307:Risk Factors; D012661:Semen / Q000737:chemistry*; D013076:Sperm Count; D013081:Sperm Motility; D014495:Universities
chemical_list: D015415:Biomarkers; C515349:GHRL protein, human; D054439:Ghrelin; C505799:obestatin, human