Patterns of protein glycosylation in bovine placentomes as a function of gestational age and in retained versus non‐retained placenta

Abstract

The formation of placenta at the beginning of pregnancy and its separation at parturition require not only deep remodelling of extracellular matrix, which mainly consists of proteins conjugated with sugar moieties, but also the cooperation with cells from both maternal and foetal parts of placenta. The aim of the study was to compare the patterns of selected conjugated proteins with sugar moieties between pregnant and term placenta as well as between released and retained placenta in cows. Placental samples from healthy pregnant cows (3–5 months of pregnancy) were collected at a slaughterhouse (n = 6), and parturient samples were collected during caesarean section at term and retrospectively divided into retained (n = 6) and released (n = 6). The pattern of selected sugar moieties conjugated with proteins was detected by use of lectin blotting with Phaseolus Vulgaris leucoagglutinin, Maackia Amurensis and Sambucus Nigra (Elderberry). The comparison and analysis of obtained band patterns showed differences between their number, molecular weight and abundance related to the intensity of staining. Samples from 3 to 4 months showed similarities, while at the 5th month, clear differences were visible in all 3 lectins, which were used in this study. Samples from retained/released placenta expressed significant differences in PHA‐L and SNA pattern in the foetal part. Obtained results indicate that the development of placenta related to extracellular matrix and accompanying cells from both sides of placenta shows dynamic changes during pregnancy. Moreover, in the case of animals with the retention of foetal membranes the patterns of proteins conjugated with sugar moieties are altered, suggesting that the changes in extracellular matrix metabolism can be involved in the attachment and detachment of the placenta in cows.

Activity of selected glycosidases and availability of their substrates in bovine placenta during pregnancy and parturition with and without retained foetal membranes

“…The examination of different stages of bovine pregnancy by use of 13 lectins in bovine endometrium and chorion showed differences in profile of sugar moieties detected by staining with Leukoagglutinin (PHA‐L) from Phaseolus vulgaris (Munson et al., 1989). Studies of our team with PHA‐L (binding to β‐1,6‐linkage), Sambucus nigra agglutinin (SNA, binding sialic acid in α‐2,6‐linkage) and Maakia amurensis lectin (MAL, binding sialic acid in α‐2,3‐linkage) confirmed the differences in sugar patterns in placental tissues during bovine pregnancy (Wawrzykowski et al., 2019). Moreover, the differences in the concentration of decorin (ECM glycoprotein) in bovine placental tissues were reported by our team (Franczyk, Wawrzykowski, & Kankofer, 2018).…”

“…As substrate specificity for examined enzymes is low, it is difficult at this stage to define which particular proteins are affected by deglycosylation, but these results should indicate that altered glycoprotein metabolism can be partly responsible for improper detachment of maternal and foetal part of bovine placenta. Based on our previous results, it can be hypothesized that worth considering sugars could be NeuNAc_2,3Gal_1‐, Tri/tetra‐antennary, non‐bisected complex N ‐linked sequences and NeuNAc_2,6Gal/GalNAc‐ (Wawrzykowski et al., 2019).…”

“…It may indicate disturbances related to polysaccharide and protein metabolism. Latest study of our group with the use of selected lectins allowed for the determination of altered profile of glycosylated proteins in pregnancy and parturition with and without retained foetal membranes (Wawrzykowski, Franczyk, & Kankofer, 2019).…”

Latest update on predictive indicators, risk factors and ‘Omic’ technologies research of retained placenta in dairy cattle – A review

“…It was reported that the development of the placenta related to the extracellular matrix and accompanying cells from both sides of the placenta shows dynamic changes in sugar moieties during pregnancy. Moreover, in the case of animals with the retention of foetal membranes, the patterns of proteins conjugated with sugar moieties are altered, suggesting that the changes in extracellular matrix metabolism can be involved in the attachment and detachment of the placenta in cows (Wawrzykowski et al., 2019). Matrix metalloproteinases (MMPs) and counteracting tissue inhibitors of metalloproteinases (TIMPs) are balancing extracellular matrix (ECM) formation and degradation.…”

Molekulargenetische und proteinanalytische Untersuchungen trächtigkeitsassoziierter Glykoproteine beim Rind

“…B. Galektin) (Kaltner & Stierstorfer, 1998) in vielen verschieden Organismen zu finden sind (Goldstein et al, 1980;Barondes, 1981;Lis & Sharon, 1986). Aufgrund ihrer Eigenschaften könnten Lektine spezifische Glykanmotive der boPAGs erkennen und binden, wodurch sie einen wichtigen Beitrag zur Adhäsion zwischen maternalem Endometrium und fetalem Allantochorion leisten (Clark, 2015;da Anunciação et al, 2017;Wawrzykowski et al, 2019). Eine Veränderung der Glykanstruktur von boPAGs zum Zeitpunkt der Geburt (Klisch et al, 2006 könnte dann wiederum eine entscheidende Rolle beim Lösen dieser Verbindung spielen (Clark, 2015;Wawrzykowski et al, 2019).…”