Recombinant SPINK3 improves ram sperm quality and in vitro fertility after cryopreservation

ZALAZAR, LUCÍA; INIESTA CUERDA, MARIA; SÁNCHEZ-AJOFRÍN, IRENE; GARDE, JOSE JULIAN; SOLER VALLS, ANA JOSEFA; CESARI, ANDREINA

THERIOGENOLOGY

ELSEVIER SCIENCE INC

Lugar: Amsterdam; Año: 2020 vol. 144 p. 45 - 55

0093-691X

Capacitation-like changes affect sperm of several species, such as ram, reducing cell survival and fertilizing competence. Proteins from seminal plasma stabilize sperm plasma membranes, being an interesting focus to develop strategies for improving cryopreserved ram semen performance. To date, biotechnologies are focused to reduce damage in frozen-thawed ram spermatozoa through the addition of bioactives. Serine Protease Inhibitor Kazal-type 3 (SPINK3) is a little protein synthesized by mouse seminal vesicle and secreted to seminal plasma. While attached to the sperm, this protein binds to non-capacitated sperm and blocks calcium entry, avoiding a premature physiological capacitation and consequently, acrosome reaction. Due to these characteristics, SPINK3 has been proposed as a decapacitating factor.The aim of this work was to assess whether heterologous SPINK3 is able to protect ram sperm from the well-known cell damages produced by freezing/thawing and to understand the mechanisms by which it is acting. Sperm were supplemented with 13 µM SPINK3 before freezing in an egg yolk-based extender or after thawing and selection. Under both conditions, SPINK3 decreased intracellular calcium content (p