title: Functional implications of membrane modification with semenogelins for inhibition of sperm motility in humans.
abstract: Semenogelin I and II (Sgs) are the major component of human semen coagulum. The protein is rapidly cleaved after ejaculation by a prostate-specific antigen, resulting in liquefaction of the semen coagulum and the progressive release of motile spermatozoa. Sgs inhibit human sperm motility; however, there is currently no information on its effect on the sperm membrane. This study investigated the role of Sgs on human sperm motility through regulation of membrane potential and membrane permeability. Fresh semen samples were obtained from normozoospermic volunteers, and studies were conducted using motile cells selected using the swim-up method. Sgs changed the characteristics of sperm motion from circular to straightforward as evaluated by a computer-assisted motility analyzer, and all parameters were decreased more than 2.5 mg/mL. The results demonstrate that Sgs treatment immediately hyperpolarized the membrane potential of swim-up-selected sperm, changed the membrane structure, and time-dependently increased membrane permeability, as determined through flow cytometric analysis. The biphasic effects of Sgs were time- and dose-dependent and partially reversible. In addition, a monoclonal antibody against Sgs showed positive binding to cell membrane proteins in fixed cells, observed with confocal fluorescence microscopy. These results demonstrate that Sgs modifies the membrane structure, indirectly inhibiting motility, and provides suggestions for a therapy for male infertility through selection of a functional sperm population using Sgs.
authors.affiliation: Biomedical Engineering Center, Toin University of Yokohama, 1614 Kurogane-cho, Aoba-ku, Yokohama, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Yoshida
authors.forename: Zoárd Tibor
authors.initials: ZT
authors.lastname: Krasznai
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Krasznai
authors.forename: Miki
authors.initials: M
authors.lastname: Yoshiike
authors.forename: Natsuko
authors.initials: N
authors.lastname: Kawano
authors.forename: Manabu
authors.initials: M
authors.lastname: Yoshida
authors.forename: Masaaki
authors.initials: M
authors.lastname: Morisawa
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Tóth
authors.forename: Zsuzsa Kassai
authors.initials: ZK
authors.lastname: Bazsáné
authors.forename: Teréz
authors.initials: T
authors.lastname: Márián
authors.forename: Teruaki
authors.initials: T
authors.lastname: Iwamoto
mesh_terms: D002462:Cell Membrane / Q000502:physiology; D002463:Cell Membrane Permeability / Q000502:physiology*; D006801:Humans; D008297:Male; D008564:Membrane Potentials / Q000502:physiology*; D012661:Semen / Q000166:cytology / Q000502:physiology*; D029607:Seminal Vesicle Secretory Proteins / Q000378:metabolism*; D013081:Sperm Motility / Q000502:physiology*
chemical_list: D029607:Seminal Vesicle Secretory Proteins; C424482:seminal vesicle-specific antigen