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It was found that hyaluronic acid is the most abundant glycosaminoglycan (GAG) both in the umbilical cord arteries and in the umbilical cord veins. Chromatographic and as well as electrophoretic studies demonstrated that EPH-gestosis (Edema-Proteinuria-Hypertension), the most common pathological syndrome occurring in pregnancy, is accompanied by premature replacement of hyaluronic acid by sulphated GAGs in the investigated arteries but not in the veins. Such a replacement is a characteristic feature of the ageing process. One may conclude that EPH-gestosis is associated with a "premature ageing" of the umbilical cord arterial walls. The mechanism and possible role of this phenomenon in pathology are discussed.
Proteoglycans of Wharton’s jelly contain mainly chondroitin/dermatan sulphate chains. The predominant proteoglycan is decorin (core proteins of 45 and 47 kDa), although the core proteins of biglycan (45 kDa), versican (260 kDa) and of other proteoglycans (90, 110, 220 kDa) were also detected (Gogiel et al., 2003). The aim of the present study was to compare the proteoglycan composition of Wharton’s jelly of newborns delivered by healthy mothers and those with pre-eclampsia. Proteoglycans from pre-eclamptic Wharton’s jelly had a higher sulphated glycosaminoglycan/protein ratio than those of normal tissue. Pre-eclampsia is associated with a lower level of all proteoglycan core proteins, especially those of higher molecular mass (such as versican), although the same set of core proteins were found in normal and pre-eclamptic Wharton’s jelly. The alterations in the proteoglycan composition of Wharton’s jelly may affect the mechanical properties of the umbilical cord and, in the case of pre-eclampsia, disturb foetal blood circulation.
Proteoglycans (PGs) were dissociatively extracted from human umbilical cord arteries (UCAs) with 4 M guanidine hydrochloride containing Triton X-100 and protease inhibitors, purified by Q-Sepharose anion exchange chromatography and lyophilized. They were analysed by gel filtration, SDS/PAGE and agarose gel electrophoresis before and after treatment with chondroitinase ABC. It was found that the PG preparation was especially enriched in chondroitin/dermatan sulphate PGs. The predominant PG fraction included small PGs that emerged from Sepharose CL-2B with Kav = 0.74. Their molecular mass, estimated by SDS/PAGE, was 160-200 kDa and 90-150 kDa, i.e. it was typical for biglycan and decorin, respectively. Treatment with chondroitinase ABC yielded the core proteins of 45 and 47 kDa, characteristic for both small PGs. Remarkable amounts of the 45 kDa protein were detected in non-treated PG samples, suggesting the presence of free core proteins of biglycan and decorin. Large PGs were present in lower amounts. In intact form they were eluted from Sepharose CL-2B with Kav = 0.17 and 0.43. Digestion with chondroitinase ABC yielded the core proteins with a molecular mass within the range of 180-360 kDa but predominant were the bands of 200, 250 and 360 kDa. The large PGs probably represent various forms of versican or perlecan bearing chondroitin sulphate chains.
Extracellular matrix components of benign ovarian tumours (cystadenoma, adenofibroma, cystadenofibroma) were analysed. The investigated tumours contained twice as much collagen than control ovarian tissues. Significant alterations in mutual quantitative relationships between collagens of various types were observed. The proportion of type I collagen decreased and that of type III collagen increased. The accumulation of collagen was accompanied by a reduction in sulphated glycosaminoglycan content whereas the amount of hyaluronic acid was not changed. Dermatan sulphate was the most abundant glycosaminoglycan component. It is suggested that the accumulation of collagen (natural barrier to the migration of tumour cells) and underexpression of glycosaminoglycans/proteoglycans (binding some growth factors and interleukins) may exert an inhibitory effect on tumour growth.
Human serum contains several glycosaminoglycans (GAGs), mainly chondroitin sulphates and significantly less of heparan sulphate + heparin and dermatan sulphate. The non-insulin-dependent diabetes mellitus (with vascular complications) was associated with a significant increase in total serum GAG concentration, mainly of chondroitin sulphates and dermatan sulphate, with a simultaneous decrease in heparan sulphate + heparin level. These alterations were much more evident in patients with poor metabolic control. Hyaluronic acid (undetectable in healthy subjects and in patients with good metabolic control) appeared only in trace amounts in poorly controlled diabetic individuals. The obtained data allow to conclude that the diabetes mellitus-associated disturbances in tissue GAG metabolism lead to significant alterations in serum GAG composition.
The design of liposomes with a hydrophilic/steric barrier at their bilayer surface allows the modification of their pharmacokinetics and reduces the uptake by the RES. Liposomes can be coated by hydrophilic molecules such as polysaccharides, which disguise the vesicle surface by creating a three-dimensional matrix near them and prevent the binding of plasma proteins and their recognition by some cellular receptors. All these considerations, and previous results obtained in our laboratory showing the formation of stable GAG-liposome complexes, have lead us to think about the use of the negatively charged glycosaminoglycans (GAGs), alternately to other molecules such as the monosialoganglioside GM1, more expensive, or polyethylene glycol (PEG-PE) that can disturb the structural organization of the bilayer. The present paper describes the effect of the incorporation of GAGs to phospholipid vesicles, in relation to their electrical and permeability properties. The results obtained show that there is an effective coating of the bilayer surface when glycosaminoglycans are added to liposome suspensions. The shielding of the negative surface charge by the neutral hyaluronic acid, in the absence of calcium, and the increase in the negative charge when the negative polyelectrolytes chondroitin sulfate, heparin or dextran sulfate are added to calcium-containing liposome suspensions account for the formation of stable liposome-GAG complexes. Moreover, the reduced permeability of the GAG-coated liposomes points out on their ability to hold encapsulated drugs and, so, their potential usefulness as drug-sustained release carriers. The hydrophilic coating will give to these liposomal carriers long-circulating properties.
The walls of human abdominal aortas and atherosclerosis-induced aneurysms contain similar amounts of collagen. The quantitative ratio between collagens of various types of this protein does not differ significantly either, whereas solubility of the collagen in aneurysmal wall and its susceptibility to the action of EDTA are distinctly decreased. In contrast with collagen, the amount of elastin in aneurysms is significantly lower. Total amount of glycosaminoglycans slightly decreased as compared with that of normal tissue, but the ratio of particular compounds varies. The percentage of chondroitin sulphate is increased and that of heparan sulphate significantly decreased. The significance of these changes in pathogenesis of aneurysms is discussed.
Low molecular mass, heparin-binding proteins from seminal plasma play an important role in gametes interaction whereas plasmatic Zn2+-binding proteins stabilize chromatin and plasmalemma structures and protect spermatozoa in the female reproductive tract. By means of affinity chromatography the heparin- and Zn2+-binding proteins were isolated from boar seminal plasma and both preparations were analyzed by reverse HPLC. Most of the proteins bound to heparine and Zn2+-ions were classified as spermadhesins. Three fractions binding exclusively Zn2+ were isolated. They differ in amino-acid composition, content of glucosamine and content of protein components revealed by SDS/PAGE.
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