title: CagA-positive Helicobacter pylori infection and reduced sperm motility, vitality, and normal morphology.
abstract: Helicobacter pylori (HP) infection, particularly when caused by strains expressing CagA, may be considered a concomitant cause of male and female reduced fertility. This study explored, in 87 HP-infected males, the relationship between infection by CagA-positive HP strains and sperm parameters. HP infection and CagA status were determined by ELISA and Western blotting; semen analysis was performed following WHO guidelines. The amino acid sequence of human enzymes involved in glycolysis and oxidative metabolism were "blasted" with peptides expressed by HP J99. Thirty-seven patients (42.5%) were seropositive for CagA. Sperm motility (18% versus 32%; P < 0.01), sperm vitality (35% versus 48%; P < 0.01) and the percentage of sperm with normal forms (18% versus 22%; P < 0.05) in the CagA-positive group were significantly reduced versus those in the CagA-negative group. All the considered enzymes showed partial linear homology with HP peptides, but four enzymes aligned with four different segments of the same cag island protein. We hypothesize a relationship between infection by strains expressing CagA and decreased sperm quality. Potentially increased systemic levels of inflammatory cytokines that occur in infection by CagA-positive strains and autoimmune phenomena that involve molecular mimicry could explain the pathogenetic mechanism of alterations observed.
authors.affiliation: Department of Molecular and Developmental Medicine, University of Siena, Policlinico S. Maria alle Scotte, V. le Bracci, 53100 Siena, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Moretti
authors.forename: G
authors.initials: G
authors.lastname: Collodel
authors.forename: L
authors.initials: L
authors.lastname: Mazzi
authors.forename: M S
authors.initials: MS
authors.lastname: Campagna
authors.forename: N
authors.initials: N
authors.lastname: Figura
mesh_terms: D000293:Adolescent; D000328:Adult; D000942:Antigens, Bacterial / Q000097:blood*; D001426:Bacterial Proteins / Q000097:blood*; D016022:Case-Control Studies; D002470:Cell Survival; D016481:Helicobacter Infections / Q000175:diagnosis / Q000473:pathology*; D016480:Helicobacter pylori / Q000472:pathogenicity; D006801:Humans; D008297:Male; D008875:Middle Aged; D013076:Sperm Count; D013081:Sperm Motility; D013094:Spermatozoa / Q000473:pathology / Q000502:physiology*
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C080866:cagA protein, Helicobacter pylori