The plasminogen activator system in the ovine placentome during late gestation and stage‐two of parturition

Abstract

The process of placental separation is not completely understood. In domestic animals, especially cattle, it is important that expulsion of the fetal membranes takes place in a timely manner in order to achieve maximal reproductive efficiency. The activity of the matrix-metalloprotease (MMP) family of proteases is known to be reduced in placentomes from cases of retained placenta. Members of the MMP family are known to be activated by the plasminogen activator (PA) family of proteases. We hypothesized that the expression and activity of the PA family increase in the cotyledon and/or caruncle as parturition approaches, with maximal expression and activity at parturition. To test this hypothesis, we performed reverse-transcriptase quantitative PCR and plasminogen-casein zymography to detect the presence and activity of PA family members in the placentome leading up to and during parturition in spontaneous and dexamethasone-induced parturient ewes. The results from our experiments indicated that serine proteases inhibitor E1 (SERPINE1) mRNA abundance in the cotyledon was different between treatment groups (P = 0.0002). In the caruncle, gene expression for plasminogen activator urokinase-type (PLAU) was different (P = 0.0154), and there was a strong trend for differences in SERPINE1 expression (P = 0.0565). These results demonstrate that expression of the PA system in the placentome changes from late pregnancy to parturition, and the presence or activity of these enzymes may occur after fetal expulsion.

Two treatment protocols for induction of preterm parturition in ewes—Evaluation of the effects on lung maturation and lamb survival

“…There are inconsistent reports about this phenomenon in sheep. Some authors have not observed an increased occurrence of RFM following medically induced parturition (Adams and Wagner, 1970;Kastelic et al, 1996;Mc Neel et al, 2013), however Leontides et al (2000) described RFM in all six of six ewes after induced parturition. Our study supports these latter findings and shows a high incidence (52%) of RFM following preterm induction of parturition with dexamethasone.…”

Molecular Mechanism and Pathways of Normal Human Parturition in Different Gestational Tissues: A Systematic Review of Transcriptome Studies

“…Expression of SERPINE1 was also found to be increased in myometrium and placenta during labor, which might be due to the elevated glucocorticoids (Medcalf et al, 1988). Aside from the ability to inhibits plasminogen activator, SERPINE1 also regulates cell adhesion to extracellular matrix, and SERPINE1 in the maternalfetal interface disrupts the adhesion of cotyledon to caruncle which results in placental separation and expulsion (Burghardt et al, 2009;McNeel et al, 2013).…”