Distribution of the glycoconjugate oligosaccharides in the human placenta from pregnancies complicated by altered glycemia: lectin histochemistry

Abstract

The aim of this study was to investigate the distribution of the oligosaccharides of the glycoconjugates in placentas from pregnancies complicated by different degree of altered glycaemia. Placentas from women with physiological pregnancies (group 1), with pregnancies complicated by minor degree of glucose intolerance (group 2) and with pregnancies complicated by gestational diabetes mellitus (GDM) treated with insulin (group 3) were collected. Ten lectins were used (ConA, WGA, PNA, SBA, DBA, LTA, UEA I, GSL II, MAL II and SNA) in combination with chemical and enzymatic treatments. The data showed a decrease of sialic acid linked alpha(2-6) to galactose/N-acetyl-D-galactosamine and an increase of N-acetyl-D-glucosamine in the placentas of the pathological groups, in particular the group 3, comparing to the group 1. A decrease of L-fucose (LTA) and D-galactose-(beta1-3)-N-acetyl-D-galactosamine, and an increase and/or appearance of L-fucose (UEA I) and N-acetyl-D-galactosamine were observed in both the pathological groups, particularly in the group 2, with respect to the group 1. In GDM, and even in pregnancies with a simple alteration of maternal glycaemia, the changes in the distribution of oligosaccharides could be related to alteration of the structure and functionality of the placenta.

Intermediate Filament Proteins Expression and Carbohydrate Moieties in Trophoblast and Decidual Cells of Mature Cat Placenta

“…In pregnant women suffering altered glycaemia, major changes in placental affinity for SBA, PNA and DBA were reported (Sgambati et al. ). Also, qualitative changes in glycosylation pattern of specific placental glycoproteins between normal and missed abortion placentae were reported in humans (Serman et al.…”

N-Glycosylation Pattern of Human Placental Insulin-Like Growth Factor and Insulin Receptors in Well-Controlled Pregestational Diabetes Mellitus

“…Using the mass spectrometric analysis of the glycans from these cells they obtained very similar profiles, suggesting that any changes in glycosylation most likely occur on specific proteins, rather than globally (20). In analysing the saccharide content of glycoconjugates in the human placental cells from pregnancies complicated by altered glycemia (minor degree of glucose intolerance or gestational diabetes mellitus), Sgambati et al (21) showed a decrease in the content of Sia a2,6-linked to galactose (Gal)/GlcNAc and in cre ase in GlcNAc in the placentas from pathological groups, in particular in gestational diabetes mellitus. On the other hand, the placentas from mothers with a minor degree of glucose intolerance had an increase of UEA I-reactive L-Fuc (21).…”

“…In analysing the saccharide content of glycoconjugates in the human placental cells from pregnancies complicated by altered glycemia (minor degree of glucose intolerance or gestational diabetes mellitus), Sgambati et al (21) showed a decrease in the content of Sia a2,6-linked to galactose (Gal)/GlcNAc and in cre ase in GlcNAc in the placentas from pathological groups, in particular in gestational diabetes mellitus. On the other hand, the placentas from mothers with a minor degree of glucose intolerance had an increase of UEA I-reactive L-Fuc (21). Women with pregesta tional IDDM were not examined.…”

State-of-the-art technologies, current opinions and developments, and novel findings: news from the field of histochemistry and cell biology

“…Apparently, adipokines play an important role in adapting the energetic metabolism at the maternalfetal interface, and dysregulation of the receptors for these adipokines has been shown in gestational diabetes mellitus (for review, see Sgambati et al 2007). Leptin appears to be involved in embryo metabolism and may participate in embryo-maternal crosstalk, but the role of adiponectin for fertility is not clear yet.…”