Soluble syndecan-1 and glycosaminoglycans in preeclamptic and normotensive pregnancies

Preeclampsia, an important cause of maternal and fetal morbidity and mortality, is associated with increased sFLT1 levels and with structural and functional damage to the glycocalyx contributing to endothelial dysfunction. We investigated glycocalyx components in relation to preeclampsia in human samples. While soluble syndecan-1 and heparan sulphate were similar in plasma of preeclamptic and normotensive pregnant women, dermatan sulphate was increased and keratan sulphate decreased in preeclamptic women. Dermatan sulphate was correlated with soluble syndecan-1, and inversely correlated with blood pressure and activated partial thromboplastin time. To determine if syndecan-1 was a prerequisite for the sFlt1 induced increase in blood pressure in mice we studied the effect of sFlt1 on blood pressure and vascular contractile responses in syndecan-1 deficient and wild type male mice. The classical sFlt1 induced rise in blood pressure was absent in syndecan-1 deficient mice indicating that syndecan-1 is a prerequisite for sFlt1 induced increase in blood pressure central to preeclampsia. The results show that an interplay between syndecan-1 and dermatan sulphate contributes to sFlt1 induced blood pressure elevation in pre-eclampsia.

Properties, bioactive potential and extraction processes of glycosaminoglycans: an overview

ABSTRACT: Glycosaminoglycans (GAGs) are long-chain polysaccharides that are divided into sulphates and non-sulphates, these being chondroitin sulphate, heparan sulphate, dermatan sulphate, heparin sulphate and the only non-sulphate in the group is hyaluronic acid. GAGs are obtained from animal tissue and by an expensive low-yield extraction process; however, they are highly commercially valued polysaccharides and exploited in the biomedical market. Their disaccharidic composition, chain length and sulfation pattern present great variability depending on the species and extraction factors. GAGs possess immunomodulatory, antioxidant, antiviral, anti-inflammatory, neuroprotective, antiproliferative and anticoagulant properties, functioning as therapeutic agents modulating an array of biological processes. This report presents the general aspects of each GAG, source and extraction process, in addition to the characteristics that give them the most varied therapeutic properties and pharmacological applications.

Analysis of Chondroitin/Dermatan Sulphate Disaccharides Using High-Performance Liquid Chromatography

Chondroitin sulphates belong to a group of naturally occurring glycosaminoglycans and play a role in many physiological processes including ageing and the effects of various diseases. Research into chondroitin sulphates has found that the most important analytes are 4- and 6-sulphated disaccharides. We developed an HPLC method for the separation and quantification of underivatized chondroitin/dermatan sulphates—unsaturated disaccharides (4- and 6-sulphated disaccharides). This method is based on the separation of disaccharides by amido as well as amino columns under acidic conditions. These columns enabled the successful separation of 4- and 6-sulphated disaccharides using 50 (amido column) and 25 mmol/L (amino column) phosphate buffer, pH 4.25 (detection at 230 nm), at retention times of less than 10 min. The limit of quantification was 0.5 μg/mL. The applicability of this method was demonstrated through analysis of unsaturated disaccharides produced from the enzymatic digestion of chondroitin/dermatan sulphates of the solubilized extracellular matrix produced from porcine urinary bladder and human umbilical cord.

Dermatan sulphate promotes neuronal differentiation in mouse and human stem cells

Dermatan sulphate (DS), a glycosaminoglycan, is present in the extracellular matrix and on the cell surface. Previously, we showed that heparan sulphate plays a key role in the maintenance of the undifferentiated state in mouse embryonic stem cells (mESCs) and in the regulation of their differentiation. Chondroitin sulphate has also been to be important for pluripotency and differentiation of mESCs. Keratan sulphate is a marker of human pluripotent stem cells. To date, however, the function of DS in mESCs has not been clarified. Dermatan 4 sulfotransferase 1, which transfers sulphate to the C-4 hydroxyl group of N-acetylgalactosamine of DS, contributes to neuronal differentiation of mouse neural progenitor cells. Therefore, we anticipated that neuronal differentiation would be induced in mESCs in culture by the addition of DS. To test this expectation, we investigated neuronal differentiation in mESCs and human neural stem cells (hNSCs) cultures containing DS. In mESCs, DS promoted neuronal differentiation by activation of extracellular signal-regulated kinase 1/2 and also accelerated neurite outgrowth. In hNSCs, DS promoted neuronal differentiation and neuronal migration, but not neurite outgrowth. Thus, DS promotes neuronal differentiation in both mouse and human stem cells, suggesting that it offers a novel method for efficiently inducing neuronal differentiation.

Effect of dermatan sulphate on a C57-mouse model of pulmonary fibrosis

Objective To test the antifibrotic effect of dermatan sulphate in a bleomycin-induced mouse model of pulmonary fibrosis. Methods C57 mice were randomly divided into four experimental groups: saline-treated control group, bleomycin-induced fibrosis group, prednisolone acetate group and dermatan sulphate group. Lungs were assessed using the lung index, and the extent of interstitial fibrosis was graded using histopathological observation of haematoxylin & eosin-stained lung tissue. Lung tissue hydroxyproline levels and blood fibrinogen levels were measured using a hydroxyproline colorimetric kit and the Clauss fibrinogen assay, respectively. Tissue-type plasminogen activator (tPA) was measured using a chromogenic tPA assay kit. Results Lung index values were significantly lower in the dermatan sulphate group versus the fibrosis group. Histopathological analyses revealed that dermatan sulphate treatment ameliorated the increased inflammatory cell infiltration, and attenuated the reduction in interstitial thickening, associated with bleomycin-induced fibrosis. Hydroxyproline and fibrinogen levels were decreased in the dermatan sulphate group versus the fibrosis model group. Dermatan sulphate treatment was associated with increased tPA levels versus controls and the fibrosis group. Conclusions Damage associated with bleomycin-induced pulmonary fibrosis was alleviated by dermatan sulphate.