S100A6 and its extracellular targets in Wharton's jelly of healthy and preeclamptic patients.

INTRODUCTION: In this work we compared the level, localization and binding partners of a calcium binding protein, S100A6, in extracellular matrix of Wharton's jelly of healthy and preeclamptic patients. METHODS: Studies were performed on the umbilical cords taken from 10 newborns delivered by healthy and 10 newborns delivered by preeclamptic mothers. To characterize S100A6 in Wharton's jelly immunoblotting and immunohistochemistry were applied. For identification of S100A6 targets pull down assays and mass spectrometry were performed. Direct interaction of S100A6 with its targets was checked by ELISA while co-localization of these proteins was analyzed by immunofluorescence staining. RESULTS: We have found that the level of S100A6 in Wharton's jelly is higher in patients with preeclampsia than in healthy ones and that post-translational modifications of S100A6 in preeclamptic tissue are different than those of S100A6 in control. We have identified several proteins that might interact with S100A6, among them are lumican and PRELP, found in Wharton's jelly of healthy and preeclamptic patients, and IGFBP-1 identified, as an S100A6 target, only in preeclamptic tissue. We have shown that the interactions between S100A6 and these proteins are direct and that IGF-1 competes with S100A6 for binding to IGFBP-1. CONCLUSION: In Wharton's jelly of preeclamptic tissue S100A6 is up-regulated and binds to different targets than in control. This suggests involvement of S100A6 in development of preeclampsia.

Spin wave excitations of a magnetic pillar with dipolar coupling between the layers.

It is demonstrated analytically that the spectrum of small-amplitude spatially uniform magnetization excitations in an in-plane magnetized magnetic pillar with two ferromagnetic layers coupled by dipole-dipole interaction can be approximately described by the traditional Kittel formula with reduced saturation magnetization and effective anisotropy field. The spectrum consists of a quasi-symmetric and a quasi-antisymmetric mode, and the apparent reduction of saturation magnetization for the quasi-symmetric mode (≤50%) is much larger than that for the quasi-antisymmetric mode (≤10%). The effect of dynamic dipolar coupling between the nano-pillar layers could be partly responsible for the apparent reduction of static magnetization seen in many spin-torque experiments performed on magnetic nano-pillars.

Fibroblast growth factors (FGF) in human myometrium and uterine leiomyomas in various stages of tumour growth.

We previously described that the growth of human uterine leiomyomas was associated with a significant remodelling of the extracellular matrix of these tumours. Significant weight-related increase of collagen and heparan sulphate contents was detected. The latter was known as a component, which bound some peptide growth factors, mainly FGFs, therefore it was decided to evaluate the amounts of acidic FGF (aFGF) and basic FGF (bFGF) in human myometrium and in leiomyomas of various weight and FGF-binding to tissue components. It was found that myometrium and uterine leiomyomas contain picogram amount of aFGF and nanogram amounts of bFGF. No free aFGF was found. Slight amounts of free bFGF were detected both in myometrium and in the tumours. The aFGF and most of bFGF existed in a form of complex with a high molecular component(s). These complexes were very stable and they did not dissociate in denaturation conditions. In comparison to myometrium the tumours contained several times more FGFs and their amounts distinctly increased during the tumour growth. The expression of FGF-receptor I (FGF RI) in the tumours was more distinct in comparison to myometrium. The extracts from myometrium did not bind exogenous 125I-bFGF. In contrast to that the tumours of different weights contained at least two high molecular weight FGF-binding components. One of them (150 kDa) corresponded to FGF-receptor. The other one (190-200 kDa) might be a heparan sulphate-proteoglycan. It seems that aFGF and bFGF play an important role in transformation of normal myometrium into leiomyoma and further growth of this tumour. The action of FGFs on tumour cells enhances biosynthesis of collagen and sulphated glycosaminoglycans, especially heparan sulphate which binds FGFs in the vicinity of cells and facilitates their interaction with membrane receptors. The effect of these processes may be further stimulation of tumour growth and remodelling of tumour extracellular matrix.

Wharton's jelly as a reservoir of peptide growth factors.

This study has assessed the amounts of insulin-like growth factor I (IGF-I), fibroblast growth factor (FGF), transforming growth factor beta (TGF-beta), platelet-derived growth factor (PDGF) and epidermal growth factor (EGF) and their binding to extracellular matrix components of Wharton's jelly. Studies were performed on the umbilical cords taken from human newborns delivered by healthy mothers. Wharton's jelly was separated and submitted to homogenisation and extraction with acetic acid and Tris-HCl buffer. The assays of growth factors were carried out with the use of ELISA commercial kits, together with SDS/polyacrylamide gel electrophoresis of tissue extracts followed by Western immunoblotting. Several growth factors, viz. acidic FGF, basic FGF, EGF, IGF-I, PDGF and TGF-beta were detected in Wharton's jelly. The amounts of these factors per gram of tissue vary from about 40 pg (EGF, PDGF) to about 200 ng (IGF-I). The amounts of peptide growth factors calculated per microgram of DNA are distinctly higher in Wharton's jelly in comparison to the umbilical cord artery. Western blot analysis demonstrated that almost the entire amount of these factors is bound to high molecular weight components. Since the number of cells in Wharton's jelly is very low and the amounts of extracellular matrix components are very high, it is concluded that the cells are strongly stimulated by peptide growth factors to produce large amounts of collagen and glycosaminoglycans.

[New collagenous proteins: FACIT collagens, transmembrane collagens and multiplexins]. / Nowe bialka kolagenowe: kolageny FACIT, transblonowe i multipleksyny.

Collagens are the main components of the extracellular matrix and they constitute about 30% of total body protein. Each collagen molecule consists of three polypeptide chains that intertwine in one or more places into triple helical domains, a very rare structure in other proteins. Nineteen collagen types have been described to date and these forming banded fibrils are the most abundant. In the last decade new collagenous proteins were discovered that have been classified into three distinct groups: fibril-associated collagens with interrupted triple helices (FACITs), transmembrane collagens and multiplexins. FACITs appear to connect collagen fibrils to other matrix components or cells. Transmembrane collagens have intracellular domains and they participate in cell adhesion and probably in signal transduction. Multiplexins are situated mainly in basement membranes and contain sequences, which demonstrate features of angiogenesis inhibitors reducing the growth of neoplasmatic tumours.

Pre-eclampsia-associated differential expression of proteoglycans in the umbilical cord arteries.

OBJECTIVE: The role of proteoglycans (PGs) of the umbilical cord arteries (UCAs) in the pathomechanism of pre-eclampsia is not known. Therefore we decided to compare the PGs of normal (control) UCAs and those of newborns delivered by mothers with pre-eclampsia. METHODS: PGs were extracted in dissociative conditions, purified by Q-Sepharose anion exchange chromatography and lyophilized. They were analyzed by gel filtration and SDS-PAGE before and after treatment with chondroitinase ABC. RESULTS: It was found that the PG preparation from pre-eclamptic UCAs had a higher amount of sulphated glycosaminoglycans (in relation to protein) than in the case of control UCAs. The predominant PG fraction included small PGs with core proteins of 45 and 47 kD, immunologically related to biglycan (45 kD) and decorin (45 and 47 kD). The expression of decorin core proteins was increased and that of biglycan slightly decreased in pre-eclamptic UCAs. Some other putative small PG core proteins (56, 53, 49, 42, 38 and 34 kD) were also found. They were present in higher amounts in pre-eclamptic UCAs. Larger PGs (core proteins of 99-110 and >150 kD), were detected in lower amounts, both in control and particularly in pre-eclamptic material. CONCLUSION: Pre-eclampsia is associated with alterations in PG composition of the UCAs. They may affect the mechanical properties of this organ and disturb fetal blood circulation.

Stimulation of collagen biosynthesis by the umbilical cord serum of newborns delivered by mothers with EPH-gestosis (preeclampsia).

Edema, proteinuria, hypertension (EPH)-gestosis, known also as preeclampsia, is the most common, pregnancy-associated pathological syndrome. It is accompanied by a significant increase in collagen content in the umbilical cord arteries and premature replacement of hyaluronic acid by sulfated glycosaminoglycans both in these arteries and in Wharton's jelly. This remodelling of the umbilical cord tissues is accompanied by a distinct increase in insulin-like growth factor-I (IGF-I) concentration in the umbilical cord serum. Such a serum introduced into the culture medium of fibroblasts growing in vitro strongly stimulated the incorporation of radioactive proline into collagen (hydroxyproline-containing and collagenase-sensitive protein). Biosynthesis of noncollagenous proteins was not stimulated. Since IGF-I is known as a stimulator of collagen and sulfated glycosaminoglycan biosynthesis, the high concentration of this growth factor in the umbilical cord plasma may be an agent responsible for preeclampsia-associated remodelling of the umbilical cord, which results in dysfunction in fetal circulation.

Preeclampsia is associated with alterations in insulin-like growth factor (IGF)-1 and IGF-binding proteins in Wharton's jelly of the umbilical cord.

Wharton's jelly is abundant in extracellular matrix, which is known as a storage site to concentrate and stabilise growth factors in the vicinity of cells. It was previously found that Wharton's jelly contains significant amounts of insulin-like growth factor (IGF)-1 and IGF-binding proteins (BPs). IGF-1 is a stimulator of biosynthetics of collagen and sulphated glycosaminoglycans. Preeclampsia (edema, proteinuria, hypertension (EPH)-gestosis) is accompanied by an accumulation of sulphated glycosaminoglycans in Wharton's jelly. IGF-1 and BPs may play an important role in such a remodelling of this tissue. It was decided to evaluate the alterations in amounts of IGF-1 and BPs in Wharton's jelly of newborns delivered by mothers with preeclampsia. Studies were performed on Wharton's jelly of 10 controls and 10 newborns delivered by mothers with preeclampsia (edema, proteinuria > 500 mg/l, arterial pressure: systolic > 140 mm Hg, diastolic > 90 mmHg). Radioimmunological techniques were employed to determine IGF-1 and IGF-BPs (BP-1 and BP-3). It was found that preeclampsia is associated with a decrease in IGF-1 and IGF-BP-1 in Wharton's jelly. A slight increase in IGF-BP-3 was found. Ligand blotting demonstrated that BP-3 (not BP-1) is a main component of Wharton's jelly, which binds IGF-1. Heparin drastically inhibited the binding of IGF-1 by BP-3. It is known from our previous studies that preeclampsia is associated with an increase in the amount of sulphated glycosaminoglycans (heparin, heparan sulphate, dermatan sulphate) in Wharton's jelly. This may be a factor, which prevents the binding of IGF-1 by BPs and facilitates the binding of IGF-1 to cells, stimulating them to produce sulphated glycosaminoglycans in Wharton's jelly.

Pre-eclampsia-induced alterations in IGF-I of human umbilical cord.

BACKGROUND: Extracellular matrix (ECM)-components serve as a storage site to concentrate and stabilise growth factors in the vicinity of cells. Human umbilical cord (UC) tissues contain significant amounts of IGF-I and IGF-binding proteins (BPs). IGF-I is known as a stimulator of collagen and sulphated glycosaminoglycans (GAGs) biosynthesis. Pre-eclampsia, the most common pregnancy associated syndrome, is accompanied by an accumulation of collagen and sulphated glycosaminoglycans in the UC. One may expect that IGF-I and BPs play an important role in such a remodelling of the UC tissue. For this reason it was decided to evaluate the alterations in amounts of IGF-I and BPs in UC serum and in the UC arterial wall of newborns delivered by mothers with pre-eclampsia. MATERIALS AND METHODS: Studies were performed on the UCs of 12 control and 12 investigated newborns, delivered by mothers with pre-eclampsia (edema, proteinuria > 500 mg l-1, arterial pressure: systolic > 140 mmHg, diastolic > 100 mmHg). Radioimmunological techniques were employed to determine IGF-I and IGF-BPs (BP-1 and BP-3). RESULTS: It was found that pre-eclampsia is associated with an increase of IGF-I concentration in the UC serum and with simultaneous decrease of its content in the umbilical cord artery (UCA). The decrease of IGF-I content in the UCA wall was accompanied by an increase of BP-3 and BP-1 in this tissue. The increase in BPs content in the UCA wall was not associated with an enhancement of IGF binding by extracts from the homogenates of arterial wall. Heparin drastically decreased the binding of IGF-I by BP-3. CONCLUSIONS: Pre-eclampsia is associated with an increase of IGF-I-concentration in the umbilical cord blood and an elevation of BPs contents in the UCA wall. Despite a high concentration of binding proteins, IGF-I is not accumulated in this tissue. High amounts of sulphated GAGs in the UCA wall may be a factor that prevents the binding of IGF-I by BPs. Free IGF-I can easily bind to cell receptors and stimulate the cells to produce collagen and sulphated GAGs in the arterial wall.

EPH-gestosis (pre-eclampsia)-induced decrease of gelatinase activity may promote an accumulation of collagen in the umbilical cord artery.

It was found in our previous paper that edema, proteinuria, hypertension (EPH)-gestosis-associated accumulation of collagen in the umbilical cord artery (UCA) is a result of increased biosynthesis and decreased degradation of this protein. It is known that the activity of collagenolytic enzymes is a main factor regulating collagen degradation rate in various tissues. For this reason it was decided to evaluate the effect of EPH-gestosis on the activity of proteolytic enzymes which may be involved in collagen degradation in the UCA wall. Proteolytic activity against bovine serum albumin, reconstituted collagen fibres and gelatin were evaluated. Latent forms of proteolytic enzymes were activated by the action of trypsin, p-chloromercuric benzoate (PCMB) and p-aminophenylmercuric acetate (APMA). A low activity of gelatinase (type IV collagenase) was detected in the extracts from the wall of the umbilical cord artery. This enzyme increased its activity several times after the action of trypsin, PCMB and APMA. EPH-gestosis results in a distinct reduction in gelatinase activity. Despite the action of activating agents the gelatinase from EPH-gestosis UCAs was considerably lower in comparison to control UCAs. It can be concluded that gelatinase of the umbilical cord artery forms an inactive complex with a tissue inhibitor of metalloproteinases. Such a complex dissociates under the action of trypsin, PCMB or APMA or sodium dodecyl sulphate. The decrease of gelatinolytic activity in the umbilical cord artery may be a factor that reduces the breakdown of collagen in the arterial wall and promotes an accumulation of this protein. The accumulation of collagen with simultaneous reduction in elastin content in the UCA may be the factors which reduce the elasticity of arterial wall and decrease the blood flow in the fetus of woman with EPH-gestosis.

The Medical Academy of Bialystok in the Jubilee Year 2000.

On the occasion of 50th anniversary of foundation of the Medical Academy of Bialystok, a brief history and the present state of the School are described. The main achievements over the last 50 years are presented.

Stimulation of glycosaminoglycan biosynthesis by umbilical cord serum of newborns delivered by mothers with EPH gestosis (preeclampsia).

OBJECTIVE: Edema, proteinuria, hypertension (EPH) gestosis, also known as preeclampsia, is the most common, pregnancy-associated pathological syndrome. It is accompanied by a significant increase in collagen content in the umbilical cord arteries and early replacement of hyaluronic acid by sulfated glycosaminoglycans (GAGs) both in these arteries and in Wharton's jelly. Such a remodelling of the umbilical cord tissues is accompanied by an increase in insulin-like growth factor-I (IGF-I) concentration in the umbilical cord serum. METHODS: Contact-inhibited human fibroblasts were incubated in Dulbecco culture medium containing control or EPH umbilical cord serum and supplemented with (14)C-glucosamine or (35)S-sulfate. Radioactive GAGs were isolated, submitted to electrophoretic fractionation and quantified. RESULTS: The presence of umbilical cord serum in culture medium strongly stimulated the incorporation of (14)C-glucosamine and (35)S-sulfate into GAGs synthesized by these cells. EPH serum was much more active in stimulation of sulfated GAGs biosynthesis than control serum, whereas the biosynthesis of hyaluronic acid was stimulated by both sera to a similar degree. CONCLUSION: Since IGF-I is known as a stimulator of collagen and sulfated GAG biosynthesis, the high concentration of this growth factor in the umbilical cord plasma may be responsible for preeclampsia-associated remodeling of the umbilical cord.

[Cathepsin A activity in the aqueous humor in patients with cataract, absolute glaucoma and intraocular tumors]. / Aktywnosc katepsyny A w cieczy wodnistej u chorych z zacma, jaskra dokonana i guzami wewnatrzgalkowymi.

PURPOSE: To evaluate cathepsin A activity in the aqueous humor of patients with cataract, absolute glaucoma and intraocular tumors. MATERIAL AND METHODS: The studies were performed on human aqueous humor taken from anterior chamber of eye balls of patients operated because of cataract, absolute glaucoma and intraocular tumors. Cathepsin A activity was determined by the ninhydrin method with synthetic substrate (N-Cbz-Phe-Ala) at its optimum pH 5.0. RESULTS: In the human aqueous humor of the eye with cataract cathepsin A activity was more than three times higher than in the eye with choroid tumors and absolute glaucoma. No differences of enzyme activity in aqueous humor between patients with glaucoma and intraocular tumors were found. CONCLUSION: The increasing proteolytic activity of cathepsin A in aqueous humor of patients with cataract suggests its importance in cataract pathogenesis. This implies that cathepsin A is involved in development of lens opacity and is found in the aqueous humor due to diffusion from cataractous lens in which the proteolytic process prevails.

[Cathepsin A activity in the vitreous body of patients with absolute glaucoma and intraocular tumors]. / Aktywnosc katepsyny A w ciele szklistym u chorych z jaskra dokonana i guzami wewnatrzgalkowymi.

PURPOSE: To evaluate cathepsin A activity in the vitreous body of patients with absolute glaucoma and intraocular tumors. MATERIAL AND METHODS: The studies were performed on human vitreous body taken from eye balls which were enucleated because of absolute glaucoma (18 eyes) and intraocular tumors (14 eyes). Cathepsin A activity was determined by the ninhydrin method with synthetic substrate (N-Cbz-Phe-Ala) at its optimum pH 5.0. RESULTS: Cathepsin A activity in the human vitreous body in absolute glaucoma was twice as high as in intraocular tumors. CONCLUSION: Our results suggest that cathepsin A may participate in the pathogenesis of absolute glaucoma and that proteolysis may play a significant role in local destruction of the retina and the optic nerve.

Activities of some glycosaminoglycan- degrading enzymes in Wharton's jelly and their alteration in EPH-gestosis (Pre-eclampsia).

Oedema, proteinuria, hypertension (EPH)-gestosis (pre-eclampsia) is associated with a premature replacement of hyaluronic acid by sulphated glycosaminoglycans (GAGs), both in the umbilical cord arteries and in Wharton's jelly. It may be concluded from our previous report that such a phenomenon may be the result of reduction in degradation of these compounds. In order to support such a conclusion the activities of GAG-degrading enzymes in normal umbilical cord arteries and those taken from newborns delivered by mothers with EPH-gestosis were compared. It was found that EPH-gestosis results in a significant reduction in the activities of neutral endoglycosidases degrading most of the sulphated GAGs (except keratan sulphate). In the case of acidic endoglycosidases, no characteristic alterations have been found. Only the activity of heparan sulphate-degrading endoglycosidase significantly decreased. In contrast to the above-mentioned endoglycosidases, the activities of arylsulphatase B and 6-sulphatase distinctly increased. The decrease in the activities of endoglycosidases are thought to be responsible for EPH-gestosis-associated accumulation of sulphated GAGs in extracellular matrix of Wharton's jelly. This leads to the suspicion that EPH-gestosis-induced changes in the GAGs composition may alter the fibrillogenesis conditions in Wharton's jelly. The sulphated GAGs accumulated in Wharton's jelly may interact with some growth factors which modify the myofibroblasts' proliferation, gene expression, protein biosynthesis and other processes. A significance of EPH-gestosis-induced alteration in Wharton's jelly is discussed.

The activities of some glycosaminoglycan-degrading enzymes in the wall of the umbilical cord artery and their alteration in edema, proteinuria, hypertension (EPH)-gestosis.

Edema, proteinuria, hypertension (EPH)-gestosis is associated with a premature replacement of hyaluronic acid by sulphated glycosaminoglycans (GAGs), both in the umbilical cord arteries (UCAs) and in Wharton's jelly. This phenomenon may be considered as a sign of premature ageing of the umbilical cord tissues. The decrease in hyaluronic acid content in the UCA was found to be the result of reduced biosynthesis of this substance, whereas an increase in sulphated GAGs-content is rather a result of slower degradation of newly synthesised GAGs. In this study the activities of GAGs-degrading enzymes in normal umbilical cord arteries and those taken from newborns delivered by mothers with EPH-gestosis were compared. It was found that EPH-gestosis results in a significant reduction in the activities of neutral endoglycosidases degrading most of the sulphated glycosaminoglycans (with the exception of heparan sulphate). The activities of exoglycosidases also decrease but to a lesser degree. These alterations are thought to be responsible for EPH-gestosis-associated accumulation of sulphated glycosaminoglycans in the extracellular matrix of the arterial wall. Such remodelling of the arterial wall may affect foetal blood circulation. The significance of these phenomena in the pathological mechanism of EPH-gestosis is discussed.

Decreased biosynthesis of glycosaminoglycans in the skin of rats with chronic diabetes mellitus.

The skin of rats with experimental (streptozotocin-induced) chronic diabetes mellitus exhibits significant decrease in glycosaminoglycans (GAGs) content. In the present study we asked the question whether the decrease in GAGs content is a result of decline in GAG biosynthesis or an increase in their degradation. We demonstrated by a pulse-labeling experiments that diabetes results in a decrease of [14C]-glucosamine incorporation into both hyaluronic acid and sulphated GAGs. During the chase period, there was no significant degradation of the pulse-labeled GAGs, suggesting that the reduction of GAGs content in the skin of diabetic rats is a result of decrease in GAG biosynthesis. Especially the biosynthesis of sulphated GAGs is deeply reduced. This phenomenon may be one of the factors which impairs the wound healing in diabetic subjects.

Elastin of the umbilical cord arteries and its alterations in EPH gestosis (preeclampsia).

Edema, proteinuria, hypertension (EPH) gestosis is accompanied by an increase of collagen content and premature replacement of hyaluronic acid by sulfated glycosaminoglycans both in the umbilical cord arteries and in Wharton's jelly. The effect of EPH gestosis on elastin content and metabolism in the umbilical cord arterial wall was the aim of this work. Studies were performed on normal umbilical cord arteries and those taken from newborns of mothers with EPH gestosis. Elastin was isolated from the arterial wall and quantified by a dye-binding method. Biosynthesis and degradation of this protein was evaluated by a pulse-chase experiment with the use of 14C-proline. It was found that EPH gestosis is associated with a significant reduction of elastin content in the umbilical cord arteries as a result of decrease in elastin biosynthesis rate and accelerated degradation of this protein. The replacement of elastin by collagen, and hyaluronate by sulfated glycosaminoglycans, may decrease the hydration of arterial wall and reduce its elasticity. Such rearrangement of extracellular matrix of the umbilical cord arteries may affect mechanical properties of these vessels and disturb fetal blood circulation.

Accumulation of collagen in ovarian benign tumours.

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.