Hyaluronan improves neither the long-term storage nor the cryosurvival of liquid-stored CD44-bearing Al boar spermatozoa
2018 (English)In: Journal of reproduction and development, ISSN 0916-8818, E-ISSN 1348-4400, Vol. 64, no 4, p. 351-360Article in journal (Refereed) Published
Abstract [en]
Hyaluronan (hyaluronic acid, HA) apparently improves sperm survival in vitro and in vivo (oviduct), maintaining sperm motility and inducing capacitation, but not acrosome exocytosis, either by direct action as a macromolecule or via CD44 membrane receptors. This study explored ejaculated, liquid-extended pig spermatozoa to ascertain (i) the presence (Western blotting) and specific location (immunocytochemistry) of the CD44 receptor, using a specific monoclonal commercial antibody; (ii) whether the CD44 receptor changed location when exposed to bicarbonate, a capacitating trigger, in vitro; and (iii) whether the addition of HA, of molecular size comparable to that produced in the oviduct sperm reservoir (0.0625 to 2.0 mg/ml; 0 HA: control), to semen extenders would improve sperm liquid storage in vitro or cryosurvival post freezing. Variables tested were sperm velocity and progressive motility (Qualisperm (TM)), sperm viability and acrosome status, membrane integrity and early destabilization, mitochondrial activation, and superoxide production (flow cytometry). The CD44 receptor presence in ejaculated, liquid-stored AI boar spermatozoa, as confirmed by a porcine-specific monoclonal antibody, maintained its membrane location under in vitro capacitation-inducing conditions. HA exposure to 24-, 48-, or 72-h liquid-stored (17-20 degrees C) spermatozoa lowered sperm velocity in membrane-intact spermatozoa, but increased mitochondrial superoxide production. Finally, HA addition during cooling did not improve cryosurvival but did increase mitochondrial activation and membrane destabilization in surviving cells. These results confirm the existence of a CD44 receptor in pig spermatozoa, but the usefulness of adding HA for long-term storage or cryopreservation of liquid-stored, extended boar semen remains in question, thereby warranting further non-empirical analyses of HA-sperm membrane interactions.
Place, publisher, year, edition, pages
SOCIETY REPRODUCTION & DEVELOPMENT-SRD , 2018. Vol. 64, no 4, p. 351-360
Keywords [en]
CD44 receptor; Hyaluronan; Spermatozoa
National Category
Pharmacology and Toxicology
Identifiers
URN: urn:nbn:se:liu:diva-151507DOI: 10.1262/jrd.2017-141ISI: 000444069500009OAI: oai:DiVA.org:liu-151507DiVA, id: diva2:1250203
Note
Funding Agencies|Swedish Research council VR, Stockholm [521-2011-6553]; Swedish Research Council FORMAS, Stockholm [221-2011-512, 2017-00946]; FORSS (Forskningsradet i Sydostra Sverige, Grant) [473121]; Lions Forskningsfond 2016-postdoc, Linkoping, Sweden
2018-09-212018-09-212021-12-28