title: Influence of Helicobacter pylori infection on levels of ghrelin and obestatin in human semen.
abstract: Helicobacter pylori (HP) infection might have negative effects on  the semen parameters of infertile men. We explored the possibility that this  infection can influence systemic and seminal levels of ghrelin and obestatin,  hormones mainly produced by the stomach. Ghrelin and obestatin exert many  activities, including the regulation of reproductive biology, and are present  in many organs and fluids, including human semen. In 78 men, we determined HP  infection and cytotoxin-associated gene A protein (CagA) status by  enzyme-linked immunosorbent assay and Western blotting, semen quality  following World Health Organization guidelines, and ghrelin and obestatin  levels in the blood stream (47 subjects) and semen by radioimmunoassay.  Twenty-seven men (34.6%) were infected (HP+) and 11 out of 27 infected men  (40.7%) were seropositive for CagA (CagA+). Sperm motility was significantly  reduced in HP+/CagA+ men compared with HP+/CagA- men (P <  .01). Ghrelin semen levels were decreased in HP+ men compared with uninfected  individuals (P < .05), whereas they were increased in HP+/CagA+  men compared with HP+/CagA- subjects (P < .01). Ghrelin  semen concentrations in HP+/CagA- men were lower than those measured in  uninfected subjects (P < .001). Semen obestatin concentration was  increased, in a nonsignificant manner, in HP+/CagA+ men. The obestatin levels  were approximately 4 times higher than those of ghrelin in semen and  approximately half the levels of ghrelin in serum specimens of all the  analyzed groups. No significant differences were found in systemic levels of  ghrelin and obestatin in HP+ to uninfected individuals. HP infection may  influence the ghrelin seminal concentrations, probably as a response to a  negative effect of infection on the semen quality.
authors.affiliation: Department of Biomedical Sciences, Applied Biology Section, University of Siena, Policlinico Santa Maria alle Scotte, Viale Bracci, 53100 Siena, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Moretti
authors.forename: Giulia
authors.initials: G
authors.lastname: Collodel
authors.forename: Maria Stella
authors.initials: MS
authors.lastname: Campagna
authors.forename: Maria Beatrice
authors.initials: MB
authors.lastname: Franci
authors.forename: Francesca
authors.initials: F
authors.lastname: Iacoponi
authors.forename: Lucia
authors.initials: L
authors.lastname: Mazzi
authors.forename: Natale
authors.initials: N
authors.lastname: Figura
mesh_terms: D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial / Q000276:immunology; D001426:Bacterial Proteins / Q000276:immunology; D015153:Blotting, Western; D004797:Enzyme-Linked Immunosorbent Assay; D054439:Ghrelin / Q000032:analysis* / Q000097:blood; D016481:Helicobacter Infections / Q000097:blood / Q000175:diagnosis* / Q000382:microbiology; D016480:Helicobacter pylori / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011863:Radioimmunoassay; D012661:Semen / Q000737:chemistry*; D055101:Semen Analysis; D013081:Sperm Motility; D013094:Spermatozoa / Q000473:pathology
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C515349:GHRL protein, human; D054439:Ghrelin; C080866:cagA protein, Helicobacter pylori; C505799:obestatin, human