| 1. |
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| 2. |
- Chambers, R C, et al.
(author)
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Cadmium inhibits proteoglycan and procollagen production by cultured human lung fibroblasts
- 1998
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In: American Journal of Respiratory Cell and Molecular Biology. - : American Thoracic Society. - 1044-1549 .- 1535-4989. ; 19:3, s. 498-506
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Journal article (peer-reviewed)abstract
- Chronic inhalation of cadmium at the workplace or in cigarette smoke is associated with emphysema, a disease characterized by extensive disruption of lung connective tissue. We have previously shown that cadmium, at noncytotoxic doses, inhibits fibroblast procollagen production in vitro, with maximal inhibitory effects of 69 +/- 6% (P < 0.01) at 30 µM cadmium chloride (CdCl2). In this paper we show that at similar doses, cadmium also inhibits proteoglycan synthesis, with values reduced by between 36 +/- 4% (P < 0.01) and 42 +/- 6% (P < 0.01) for proteoglycans secreted into the culture media and associated with the cell layer, respectively. The greatest inhibition was obtained for the major matrix-associated proteoglycans, versican, decorin, and the large heparan sulfate proteoglycans, with synthesis values reduced by between 60 and 70%. Biglycan and other heparan sulfate proteoglycans were also affected, with synthesis values reduced by between 25 and 45%. In contrast, total protein synthesis was unaffected. Furthermore, effects of cadmium at the protein level were mirrored by reduction in messenger RNA levels for alpha1(I) procollagen, versican, and decorin. These data support the hypothesis that cadmium may play an important role in the pathogenesis of emphysema associated with chronic inhalation of cadmium fumes by inhibiting the production of connective tissue proteins.
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| 3. |
- Falconer, C, et al.
(author)
-
Changes in paraurethral connective tissue at menopause are counteracted by estrogen
- 1996
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In: Maturitas. - 0378-5122. ; 24:3, s. 197-204
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Journal article (peer-reviewed)abstract
- OBJECTIVE: To study whether the transition to menopause is accompanied by changes in the paraurethral connective tissue and if these changes are modified by estrogen replacement therapy.STUDY DESIGN: Biopsies were obtained from the paraurethral tissue from 34 women; 12 menstruating, 14 postmenopausal without estrogen treatment, and 8 with estrogen treatment. Collagen concentration and collagen extractability by pepsin digestion were measured. Proteoglycan composition and concentration were analysed using Alcian blue. The mRNA levels for collagen I and III, the small proteoglycans (PGS) decorin and biglycan, and the large proteoglycan versican, were estimated.RESULTS: The paraurethral biopsies consisted of fibrous connective tissue, with collagen fibers as dominating structure. Several proteoglycans were identified; versican, heparansulphate proteoglycans, biglycan and decorin. The small proteoglycan decorin represented 85% of all proteoglycans. The collagen concentration was almost doubled in postmenopausal biopsies compared to premenopausal. The collagen fibril organization was also changed with higher cross-linking after menopause whereas the amount and the composition of the proteoglycans were unchanged. The proteoglycan/collagen ratio was significantly decreased. Estrogen replacement therapy resulted in decreased collagen concentration, decreased cross-linking of the collagen and reversal of the PGS/collagen ratio to almost premenopausal level. The therapy resulted in increased levels of mRNA for collagen I and III which suggests that the changes are due to an increased turnover.CONCLUSION: The decrease in estrogen levels at menopause results in a connective tissue with different qualities after menopause. Estrogen replacement therapy tends to restore the metabolism of the genitourinary connective tissue to premenopausal conditions.
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| 4. |
- Falconer, C, et al.
(author)
-
Paraurethral connective tissue in stress-incontinent women after menopause
- 1998
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In: Acta Obstetricia et Gynecologica Scandinavica. - 0001-6349. ; 77:1, s. 95-100
-
Journal article (peer-reviewed)abstract
- OBJECTIVE: To study whether stress urinary incontinence after menopause is correlated to changes in the paraurethral connective tissue ultrastructure and metabolism.METHODS: Transvaginal biopsies were obtained from the paraurethral connective tissue in stress urinary incontinent women after menopause with and without estrogen replacement therapy, and from comparable controls. All the stress-incontinent women underwent urodynamic investigation. In the specimens, collagen concentration, measured as hydroxyproline, and the degree of extractability by pepsin digestion, were quantified. Proteoglycan composition and concentration were analyzed using Alcian Blue precipitation, followed by electro-phoretic separation and quantification. Using Northern blots, mRNA levels for the collagens I and III, the small proteoglycans decorin and biglycan, and the large proteoglycan versican, were quantified. Collagen structure was examined with transmission electron microscopy, and the diameters of collagen fibrils were analyzed with an interactive image analysis system (IBAS, Zeiss/Kontron).RESULTS: No significant difference in paraurethral connective tissue biochemistry or ultrastructure was registered between women with stress incontinence and controls. Estrogen replacement therapy resulted in a lower collagen concentration both between the controls (p = 0.02) and between the incontinent women (0.02). In the women with stress incontinence also the extractability by pepsin digestion was higher in the group with estrogen treatment (p = 0.004), indicating a decrease in cross-linking. The proteoglycan/collagen ratio was higher in the control group with estrogen treatment compared to untreated (p = 0.02), but no difference was found between estrogen treated and untreated incontinent women. The median collagen fibril diameter was 15% larger in the incontinent group of women without estrogen therapy compared to the control group and 5% larger when comparing the incontinent group on estrogen replacement therapy to the corresponding control group.CONCLUSION: The extracellular matrix of paraurethral connective tissue in stress urinary incontinent women after menopause reacted differently to estrogen replacement therapy compared to continent controls. In contrast to incontinent women of fertile age no major changes in collagen metabolism were found in stress urinary incontinent women after menopause.
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| 5. |
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| 6. |
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| 7. |
- Westergren-Thorsson, G., et al.
(author)
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Proteome
- 2006
-
In: Encyclopedia of Respiratory Medicine : Volume 1-4 - Volume 1-4. - 9780123708793 - 9780123708793 ; 1-4, s. 527-532
-
Book chapter (other academic/artistic)abstract
- Proteomics can be defined as the studies of protein properties on a large scale to obtain a global view of biological processes at the protein level. Essentially, proteomics requires protein separation and identification, and in many cases quantification. The cornerstones in proteomics are protein/peptide separation by gel electrophoresis and/or different chromatographic techniques, and identification by mass spectrometry followed by bioinformatic and biological interpretation of data. By combining these different separation techniques and mass spectrometry it is now possible to identify low abundant proteins with 10-1000 copies per cell. Today, substantial research efforts in proteome studies of the lung are focused on obtaining new diagnostic markers, as well as fingerprinting disease mechanisms.
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| 8. |
- Andersson, C. K., et al.
(author)
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Uncontrolled asthmatics have increased FceRI+ and TGF-β–positive MCTC mast cells and collagen VI in the alveolar parenchyma
- 2018
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In: Clinical and Experimental Allergy. - : Wiley. - 0954-7894. ; 48:3, s. 266-277
-
Journal article (peer-reviewed)abstract
- Background: Asthma has been associated with increased collagen deposition in both conducting airways and alveolar parenchyma. Mast cells (MCs) are key effector cells in asthma and have the ability to affect collagen synthesis. However, the link between clinical control and changes in bronchial and alveolar MC phenotypes and specific collagens in controlled and uncontrolled asthma remains unknown. Objective: To investigate MC phenotypes in correlation with deposition of specific collagen subtypes in patients with controlled and uncontrolled asthma as well as to healthy controls. Methods: The tissue expression of IgE+, FcεRI+ and TGF-β+ MCs, as well as immunoreactivity of collagen I, III and VI, was assessed using immunohistochemistry on bronchial and transbronchial biopsies from controlled asthmatics (n = 9), uncontrolled asthmatics (n = 16) and healthy controls (n = 8). Results: In the alveolar parenchyma, the total number of MCs, as well as the number of FcεRI+ MCs and pro-fibrotic TGF-β+ MCTC, was significantly increased in uncontrolled asthma compared to both controlled asthma and healthy controls. The proportion of TGF-β+ MCTC correlated positively to an increased immunoreactivity of alveolar collagen VI but not collagen I and III. Collagen VI was increased in the alveolar parenchyma of uncontrolled asthmatics compared to controlled asthmatics. Controlled asthmatics had an increased deposition of alveolar collagen I. In bronchi, the immunoreactivity of collagen I was increased in both controlled and uncontrolled asthmatics while collagen III was increased only in controlled asthmatics. Conclusions: Patients with uncontrolled atopic asthma have an altered pro-fibrotic MCTC phenotype in the alveolar parenchyma that is associated with alveolar collagen VI. The present data thus support distal lung mast cell and matrix changes as histopathological features of asthma that may be of particular clinical relevance in patients who have remaining symptoms despite conventional inhaler therapy.
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| 9. |
- Arroyo-Yanguas, Yolanda, et al.
(author)
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Binding, internalization, and degradation of antiproliferative heparan sulfate by human embryonic lung fibroblasts
- 1997
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In: Journal of Cellular Biochemistry. - 0730-2312. ; 64:4, s. 595-604
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Journal article (peer-reviewed)abstract
- Binding, internalization, and degradation of 125I-labeled, antiproliferative, or nonantiproliferative heparan sulfate by human embryonic lung fibroblasts was investigated. Both L-iduronate-rich, antiproliferative heparan sulfate species as well as L-iduronate-poor, inactive ones were bound to trypsin-releasable, cell-surface sites. Both heparan sulfate types were bound with approximately the same affinity to one high-affinity site (Kd approximately 10(-8) M) and to one low-affinity site (Kd approximately 10(-6) M), respectively. Results of Hill-plot analysis suggested that the two sites are independent. Competition experiments with unlabeled glycosaminoglycans indicated that the binding sites had a selective specificity for sulfated, L-iduronate-rich heparan sulfate. Dermatan sulfate, which is also antiproliferative, was weakly bound to the cells. The antiproliferative effects of heparan and dermatan sulfate appeared to be additive. Hence, the two glycosaminoglycans probably exert their effect through different mechanisms. At concentrations above 5 micrograms/ml (approximately 10(-7) M), heparan sulfate was taken up by human embryonic lung fibroblasts, suggesting that the low-affinity site represents an endocytosis receptor. The antiproliferative effect of L-iduronate-rich heparan sulfate species was also exerted at the same concentrations. The antiproliferative species was taken up to a greater degree than the inactive one, suggesting a requirement for internalization. However, competition experiments with dextran sulfate suggested that both the high-affinity and the low-affinity sites are involved in mediating the antiproliferative effect. Structural analysis of the inactive and active heparan sulphate preparations indicated that although sulphated L-iduronate appears essential for antiproliferative activity, it is not absolutely required for binding to the cells. Degradation of internalized heparan sulfate was analyzed by polyacrylamide gel electrophoresis using a sensitive detection technique. The inactive species was partially degraded, whereas the antiproliferative one was only marginally affected.
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| 10. |
- Falconer, C, et al.
(author)
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Different organization of collagen fibrils in stress-incontinent women of fertile age
- 1998
-
In: Acta Obstetricia et Gynecologica Scandinavica. - : Wiley. - 0001-6349 .- 1600-0412. ; 77, s. 87-
-
Journal article (peer-reviewed)abstract
- OBJECTIVE: The objective was to test the hypothesis that stress urinary incontinence in women is correlated to changes in the paraurethral connective tissue ultrastructure and metabolism.METHODS: Transvaginal biopsies were obtained from the paraurethral connective tissue in women of fertile age with stress urinary incontinence and in matched continent controls. All the stress-incontinent women were characterized with urodynamic investigation. In the biopsies, collagen concentration, measured as hydroxyproline, and the degree of extraction by pepsin digestion were quantified. Proteoglycan composition and concentration were analyzed using Alcian blue precipitation, followed by electrophoretic separation and quantification. Using Northern blots mRNA levels for the collagens I and III, the small proteoglycans decorin and biglycan, and the large proteoglycan versican, were quantified. Collagen organization was examined with transmission electron microscopy and the diameters of collagen fibrils were analyzed with an interactive image analysis system (IBAS, Zeiss/Kontron).RESULTS: The biochemical and morphological analyses exposed a significant difference in the paraurethral connective tissue between stress urinary incontinent women before menopause and comparable controls. The collagen concentration was almost 30% higher and the diameters of the collagen fibrils were 30% larger in the incontinent group of women. Also the organization of the collagen fibrils differed, with considerably higher cross-linking. A higher level of mRNA for collagen I and III in the incontinent group indicates that the differences can be related to an altered collagen metabolism. No change of proteoglycan amount or composition was observed, resulting in a significantly lower proteoglycan/collagen ratio in the incontinent group of women.CONCLUSION: Stress urinary incontinence in fertile women is associated with a change in collagen metabolism resulting in an increased concentration of collagen and larger collagen fibrils. These alterations should result in a more rigid form of extracellular matrix, suggesting a connective tissue with impaired mechanical function.
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| 11. |
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| 12. |
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| 13. |
- Malmström, J, et al.
(author)
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Heparan sulfate upregulates platelet-derived growth factor receptors on human lung fibroblasts
- 1998
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In: Glycobiology. - : Oxford University Press (OUP). - 0959-6658 .- 1460-2423. ; 8:12, s. 55-1149
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Journal article (peer-reviewed)abstract
- Heparan sulfate is a molecule that possesses a large structural variability and which has been shown to inhibit the proliferation of fibroblasts in vitro. The aim of this study was to determine whether the anti-proliferative effects of heparan sulfate were exerted by regulation of the activity of the platelet-derived growth factor and/or of the platelet-derived growth factor receptors. Both l-iduronate-rich, anti-proliferative and the l-iduronate-poor, non-anti-proliferative heparan sulfate species, were incubated with confluent human embryonic lung fibroblasts for 24 h. The mRNA levels for PDGF-AA, PDGF-BB, and their receptors were measured. Binding studies were performed with [125I]-PDGF-BB and [125I]-EGF for 2 h at 4 degreesC in cultures preincubated with both types of heparan sulfate for 24 h. In separate experiments, cultures were incubated together with heparan sulfate and [125I]-PDGF-BB for 2 h at 4 degreesC. Increases of two- to threefold in the mRNA levels for both the alpha- and the beta-receptors of PDGF was obtained after treatment with both types of heparan sulfate, whereas the mRNA levels of both the PDGF-AA and the PDGF-BB were essentially unaffected. A sixfold increase in binding was only noted for [125I]-PDGF-BB in cultures pre-treated with the anti-proliferative heparan sulfate for 24 h, whereas no effect was noted with use of the non-anti-proliferative heparan sulfate. Incubating the [125I]-PDGF-BB and the anti-proliferative heparan sulfate together for 2 h resulted in a smaller, threefold increase in binding. This indicates that the anti-proliferative heparan sulfate both stabilizes and increases expression of the PDGF receptors. To investigate whether the increased number of PDGF receptors could affect cell activity, cells were preincubated with anti-proliferative heparan sulfate and then treated with PDGF-BB. This resulted in an increase in mitogenicity compared to cells treated only with PDGF-BB. Neither an increase in binding for [125I-EGF] nor an increase in the mitogenic response of EGF could be observed in cultures pre-treated with the anti-proliferative heparan sulfate. The results indicate that the extracellular matrix itself may regulate important biological phenomena such as cell proliferation and matrix production through affecting the expression of receptors of PDGF, which initiate both stimulatory and inhibitory signals.
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| 14. |
- Mani, K, et al.
(author)
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Heparan/chondroitin/dermatan sulfate primer 2-(6-hydroxynaphthyl)-O-beta-D-xylopyranoside preferentially inhibits growth of transformed cells
- 1998
-
In: Cancer Research. - 0008-5472. ; 58:6, s. 104-1099
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Journal article (peer-reviewed)abstract
- Xylose forms the direct carbohydrate-protein link in extra- or pericellular proteoglycans (PGs) that are substituted with either chondroitin sulfate (CS)/dermatan sulfate (DS) and/or heparan sulfate (HS). Cell surface PGs carrying HS are important regulators of cell growth. Xylose coupled to an aromatic compound can enter cells and initiate either CS/DS synthesis or both HS and CS/DS synthesis, depending on the nature of the aromatic adduct. Here, we show that 2-(6-hydroxynaphthyl)-O-beta-D-xylopyranoside, which can prime both types of glycan chains, inhibits growth of a set of normal and transformed cells. Transformed cells are preferentially inhibited, and at a concentration of 0.15-0.20 mM xyloside, transformed cells are totally growth arrested, whereas normal cells are only < or = 50% inhibited. No inhibition of growth is observed with the stereoisomeric 2-(6-hydroxynaphthyl)-O-beta-L-xylopyranoside, which does not prime glycosaminoglycan synthesis at all; with the nonhydroxylated 2-naphthyl-O-beta-D-xylopyranoside, which only primes CS/DS synthesis under these conditions; or with p-nitrophenyl-O-beta-D-xylopyranoside, which is known to prime only CS/DS synthesis. We conclude that growth inhibition is due to priming of HS and/or CS/DS synthesis, which may either lead to the formation of specific antiproliferative glycans or glycan fragments or to interference with endogenous PG synthesis and turnover.
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| 15. |
- Söderlund, Z, et al.
(author)
-
Controlled release of growth factors using synthetic glycosaminoglycans in a modular macroporous scaffold for tissue regeneration
- 2022
-
In: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 5:1
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Journal article (peer-reviewed)abstract
- Healthy regeneration of tissue relies on a well-orchestrated release of growth factors. Herein, we show the use of synthetic glycosaminoglycans for controlled binding and release of growth factors to induce a desired cellular response. First, we screened glycosaminoglycans with growth factors of interest to determine kon (association rate constant), koff (dissociation rate constant), and Kd (equilibrium rate constant). As proof-of-concept, we functionalized an elastin-like recombinamer (ELR) hydrogel with a synthetic glycosaminoglycan and immobilized fibroblast growth factor 2 (FGF2), demonstrating that human umbilical vein endothelial cells cultured on top of ELR hydrogel differentiated into tube-like structures. Taking this concept further, we developed a tunable macroporous ELR cryogel material, containing a synthetic glycosaminoglycan and FGF2 that showed increased blood vessel formation and reduced immune response compared to control when implanted in a subcutaneous mouse model. These results demonstrated the possibility for specific release of desired growth factors in/from a modular 3D scaffold in vitro and in vivo.
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| 16. |
- Tas, Sinem, et al.
(author)
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Advanced manufacturing: three-dimensional printing and bioprinting of models of lung and airways
- 2022
-
In: 3D Lung Models for Regenerating Lung Tissue. - 9780323908726 - 9780323908719 ; , s. 171-195
-
Book chapter (peer-reviewed)abstract
- Recent advances in materials science coupled with advanced manufacturing techniques have opened up new possibilities for generating sophisticated models of lung and airways containing cells. These models can be used for studying normal tissue homeostasis as well as for modeling lung development, disease, and regeneration. Three-dimensional (3D) printing has emerged as a leading advanced manufacturing technique for generating models as well as producing clinically relevant constructs. In fact, 3D-printed, cell-free support structures have already been used clinically in a few case reports for airways. While 3D bioprinting is poised to play a major role in both preclinical and clinical science, only a few constructs containing cells have been made to date. Preclinical models of 3D-bioprinted tracheas containing cells show promise, but there is a paucity of reports for distal lung, owing to a lack of bioinks. This chapter discusses the use of advanced manufacturing to bioengineer 3D constructs for lung and airways.
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| 17. |
- Tiedemann, K, et al.
(author)
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Cytokine regulation of proteoglycan production in fibroblasts : separate and synergistic effects
- 1997
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In: Matrix (Stuttgart, Germany). - 0945-053X. ; 15:7, s. 78-469
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Journal article (peer-reviewed)abstract
- We have studied the effects of cytokines, separately or in combination, on the production of proteoglycans in confluent cultures of fibroblasts. The cytokines used were the transforming growth factor-beta (TGF-beta), the platelet derived growth factor-AA (PDGF-AA), the platelet derived growth factor-BB (PDGF-BB) and the epidermal growth factor (EGF). Hyaluronan production increased in cells treated with TGF-beta, PDGF-AA and PDGF-BB. Combining pairs of factors did not contribute further to hyaluronan production, whereas the triple combination of EGF, TGF-beta and PDGF-BB induced an additional 1.9-fold increase. Proteoglycan production was only increased by TGF-beta alone. As for hyaluronan, combining pairs of the cytokines had no further effect on metabolism, whereas the combination of EGF, TGF-beta and PDGF-BB induced a further 1.6-fold increase in production and secretion. Compared with the control, an extensive increase in proteoglycan production was generated by the combination of EGF, TGF-beta and PDGF-BB, 7-fold for biglycan, approximately 5-fold for versican and hyaluronan and 2.4-4-fold for heparan sulfate proteoglycan and decorin. Compared with TGF-beta alone, this combination increased, in falling order, the production of heparan sulfate proteoglycan, hyaluronan, biglycan, decorin and versican. The mRNA levels for the various proteoglycans did not completely agree with the changes in production, suggesting that changes not only in synthesis but also in rate of degradation generate these variations. The data indicate that cytokines cooperate to produce a proper and physiological response, one needed by the organism during physiological and pathophysiological remodeling.
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| 18. |
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| 19. |
- Westergren-Thorsson, G, et al.
(author)
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Altered dermatan sulfate proteoglycan synthesis in fibroblast cultures established from skin of patients with systemic sclerosis
- 1996
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In: Journal of Rheumatology. - 0315-162X. ; 23:8, s. 406-1398
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Journal article (peer-reviewed)abstract
- OBJECTIVE: To study whether changes in the properties of skin from patients with systemic sclerosis (SSc) are the result of altered metabolism of dermatan sulfate proteoglycans.METHODS: Fibroblast cultures were established from skin of healthy controls, and from affected and unaffected skin of patients with SSc. Synthesized proteoglycans were labeled with 3H glucosamine and 35S sulfate. The amount of mRNA of the different dermatan sulfate proteoglycans was determined by hybridization with the corresponding cDNA probes.RESULTS: A 2-fold increase in secretion of total proteoglycans was found in cell cultures from affected and normal appearing skin from patients with SSc. The production of 2 different dermatan sulfate proteoglycans was increased. Aggrecan/versican increased 4-fold and decorin 2-fold in cultures of affected skin from patients with SSc. The mRNA for decorin increased 3-fold, while the mRNA level for versican increased only slightly. Similar but less marked changes were noted in cultures from normal appearing skin. In contrast, the biglycan mRNA level decreased and the product could only be found in very small amounts in SSc cultures.CONCLUSION: This marked alteration of dermatan sulfate proteoglycan metabolism distinguishes not only affected skin but also normal appearing SSc skin from that of controls. The altered proteoglycan production may affect organization of matrix fibers and thereby the fibrotic process observed in patients with SSc.
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| 20. |
- Westergren-Thorsson, G, et al.
(author)
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Altered expression of small proteoglycans, collagen, and transforming growth factor-beta 1 in developing bleomycin-induced pulmonary fibrosis in rats
- 1993
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In: Journal of Clinical Investigation. - 0021-9738. ; 92:2, s. 7-632
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Journal article (peer-reviewed)abstract
- The development of bleomycin-induced pulmonary fibrosis in rats was studied over a period of 21 d after an intratracheal instillation of bleomycin. The expression of three small proteoglycans (biglycan, decorin, and fibromodulin), collagen III and TGF-beta 1 was studied by RNA-transfer blot analysis. The proteoglycans were also studied by SDS-polyacrylamide gel electrophoresis and Western blots. TGF-beta 1 mRNA increased threefold already on day 3 and remained elevated until day 10. After the increase of TGF-beta 1 mRNA the messages for biglycan and collagen III steadily increased to reach a maximum 10 d after bleomycin instillation. The mRNA for biglycan increased maximally fourfold and that of collagen III 2.5-fold. Decorin mRNA, in contrast to biglycan decreased and reached 20% of control on day 10. The message for fibromodulin remained constant throughout the study period. The amounts of biglycan and decorin in the tissue changed in accordance with the mRNA levels. The results corroborate and extend previous in vitro studies concerning the effect of TGF-beta 1 on the metabolism of small proteoglycans and show that these macromolecules are regulated differently also in vivo. The marked alterations of biglycan and decorin during the development of fibrosis suggests that these proteoglycans have a regulating role in this process.
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| 21. |
- Westergren-Thorsson, Gunilla, et al.
(author)
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Differential expressions of mRNA for proteoglycans, collagens and transforming growth factor-beta in the human cervix during pregnancy and involution
- 1998
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In: Biochimica et Biophysica Acta. - 0006-3002. ; 1406:2, s. 13-203
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Journal article (peer-reviewed)abstract
- During pregnancy and involution, an extensive remodelling of the human cervical connective tissue occurs. This cervical ripening is one of the most pronounced physiological remodelling processes known in human connective tissue. To investigate how the remodelling is accomplished, the levels of mRNA for collagen I and III, versican and three small proteoglycans, biglycan, decorin and fibromodulin, were evaluated using Northern blots at different stages of cervical ripening. In the corresponding biopsies the concentration of collagen and of small and large proteoglycans were determined. The role of transforming growth factor-beta (TGF-beta) as a mediator of the remodelling process was also investigated. The concentration of collagen decreased and 1 week before partus, 50% of the nonpregnant level was attained. No further decrease was noted after partus. The mRNA for collagen I and III did, however, not decrease in the term pregnant cervix 1 week before partus. Only 20-30% decrease during the final ripening just before partus was recorded. Neither did the mRNA levels of the small proteoglycans change significantly during the ripening, despite an almost 50% decrease in the concentration of the small proteoglycans. The message for versican was, however, 5-fold increased at partus and then gradually returned to nonpregnant levels within 4 days after delivery. These changes corresponded to similar changes in the concentration of the large proteoglycan. Thus, the remodelling of the cervical connective tissue is achieved by two different mechanisms, on one hand an increased turnover of collagen and the small proteoglycans, on the other a changed transcription followed by an increased production of versican. During the involution 2- to 3-fold increases in the messages for collagen I and III, and the small proteoglycans, biglycan and decorin, corresponded to increases in the concentration of the small proteoglycans and non-extractable collagen. The message for TGF-beta was increased 2-fold immediately after delivery compared with the term pregnant state. Thus, TGF-beta may be of importance for the reconstruction of the cervix, which starts immediately after partus.
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| 22. |
- Westergren-Thorsson, G, et al.
(author)
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L-iduronate-rich glycosaminoglycans inhibit growth of normal fibroblasts independently of serum or added growth factors
- 1993
-
In: Experimental Cell Research. - : Elsevier BV. - 0014-4827. ; 206:1, s. 9-93
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Journal article (peer-reviewed)abstract
- The effects of various glycosaminoglycans (GAGs) on the growth rate of normal fibroblasts and a fibrosarcoma cell line (HT 1080) were examined. Cells were grown in 96-well microplates in the absence or presence of serum mitogens, epidermal (EGF), platelet-derived (PDGF), acidic fibroblast (aFGF), or basic fibroblast growth factor (bFGF). Cell number was measured by using crystal violet to stain cell nuclei (Westergren-Thorsson, G., Onnervik, P.-O., Fransson, L.-A., and Malmström, A. J. Cell. Phys. 147, 523-530, 1991) and also by using a Coulter counter. In the presence of serum mitogens, L-iduronate (IdoA)-rich GAGs, such as dermatan sulfate, heparin, and highly sulfated heparan sulfate, inhibited proliferation of normal cells (25-35%), whereas HT 1080 cells were unaffected or slightly stimulated. Ham's F-12 supplemented with insulin and transferrin but without growth factors was able to support growth of both cell types. Under these conditions, the IdoA-rich GAGs still suppressed growth of normal cells (40-55%), whereas HT 1080 cells again responded poorly. When growth factors were added proliferation of normal fibroblasts was further stimulated, EGF being the most effective. In the presence of either EGF, PDGF, or bFGF, IdoA-rich GAGs had a sustained inhibitory effect on normal fibroblasts (30-50% at concentrations at or above 10 micrograms/ml). However, in the presence of aFGF, both IdoA-rich and IdoA-poor heparan sulfates enhanced growth (nearly twofold after prolonged exposure) suggesting a stabilization of this growth factor. In general, IdoA-rich GAGs appear to inhibit proliferation of normal cells irrespective of the type of growth factor used. Therefore, GAGs are likely to act directly on cell-derived regulatory components, either before or after internalization. As fibrosarcoma cells were much less sensitive to growth inhibition, they may contain altered receptors for GAGs.
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| 23. |
- Westergren-Thorsson, G, et al.
(author)
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Proliferation of cultured fibroblasts is inhibited by L-iduronate-containing glycosaminoglycans
- 1991
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In: Journal of Cellular Physiology. - : Wiley. - 0021-9541. ; 147:3, s. 30-523
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Journal article (peer-reviewed)abstract
- We have modified a method (Gilles et al: Anal. Biochem., 159:109-113, 1986) for measuring cell number, that is based on the binding of crystal violet to cell nuclei and used it to assay effects of various glycosaminoglycans on growth of human lung fibroblasts. The procedure was modified by growing cells in microcultures (96 well microplates) and by measuring the amount of adsorbed dye using a microplate photometer after solubilisation of the cells with detergent. There was a linear relationship between absorbance and cell number measured by a Coulter Counter. The method is rapid and sensitive and can be used for screening many samples as well as measuring growth rates at low initial cell densities. Even the low growth rates obtained in the absence of serum can be detected. Human lung fibroblasts were growth arrested by serum deprivation and then grown for periods of up to 4 days in the presence of serum and exogenously added glycosaminoglycans (range, 0.1-100 micrograms/ml). Hyaluronan, chondroitin sulfate, and dextran sulfate were without effects, whereas dermatan sulfate, certain heparan sulfates, and heparin suppressed growth (20%-50% inhibition). The antiproliferative activity of dermatan sulfate increased with increasing iduronate content. Certain heparan sulfates, with moderately high sulfate and L-iduronate contents were better inhibitors than heparin despite the fact that the latter glycan has even higher sulfate and L-iduronate contents. The antiproliferative effect of exogenous glycans appeared after a lag period of 3-4 days, suggesting that they interfered with factors produced by the cells. Furthermore, the degree of inhibition was greater when the initial cell density was low. Above a certain level of seeded cells (approx. 10,000 cells/well), there was no inhibition by any of the glycosaminoglycans. It is possible that exogenous glycans cannot overcome endogenous growth-promoting effects in densely seeded cultures.
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| 24. |
- Westergren-Thorsson, G, et al.
(author)
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TGF-beta enhances the production of hyaluronan in human lung but not in skin fibroblasts
- 1990
-
In: Experimental Cell Research. - : Elsevier BV. - 0014-4827. ; 186:1, s. 5-192
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Journal article (peer-reviewed)abstract
- Transforming growth factor-beta (TGF-beta) enhances the production of extracellular matrix components, such as type I and type III collagen, fibronectin, proteoglycans, in various cell types. The effect on hyaluronan synthesis in relation to proteoglycan synthesis has not been investigated. Human lung or skin fibroblast cultures were treated with TGF-beta in serum-free medium for various periods of time. 35SO4 or [3H]glucosamine was then added to the cultures in the absence of TGF-beta for up to 48 h. Hyaluronan and proteoglycans were isolated by ion-exchange chromatography and quantitated. TGF-beta induced a three- to fourfold increase in hyaluronan production by lung cells but had no effect on skin fibroblasts. In contrast, proteoglycan synthesis was enhanced in both cell types, although skin fibroblasts responded at lower concentrations of TGF-beta. Increased accumulation of hyaluronan was noted only in the cell medium, whereas proteoglycan accumulation was observed both in the medium and in the cell layer. The ED50 for TGF-beta on hyaluronan accumulation in lung cells was the same as that for proteoglycan accumulation, i.e., 40 pM. In skin fibroblasts the ED50 was considerably lower (4 pM). The induction time needed to attain full effect of TGF-beta was 6 h for both hyaluronan and proteoglycan synthesis. These results indicate that TGF-beta has tissue-specific effects on matrix production which may be of importance for control of cell proliferation in various disease states.
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| 25. |
- Westergren-Thorsson, G, et al.
(author)
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The synthesis of a family of structurally related proteoglycans in fibroblasts is differently regulated by TFG-beta
- 1991
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In: Matrix (Stuttgart, Germany). - 0934-8832. ; 11:3, s. 83-177
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Journal article (peer-reviewed)abstract
- Fibroblasts synthesize a variety of proteoglycans among which is a family of structurally related small proteoglycans, i.e. PG-S1 (biglycan) and PG-S2 (decorin). Fibromodulin, which is present in some tissues as a keratan sulfate proteoglycan, also belongs to this family. We have used primary fibroblasts from fetal skin and bovine sclera in culture to study the metabolism of proteoglycans. In particular the regulatory effect of transforming growth factor-beta (TGF-beta), interleukin-1 (IL-1) platelet-derived growth factor (PDGF) and dexamethasone was determined by studies of mRNA levels for these structurally related proteoglycans. Furthermore the synthesis and secretion of these macromolecules was studied using radioactive precursors. TGF-beta induced a 3-fold increase of mRNA for PG-S1, collagen I and III in both types of fibroblasts. mRNA for PG-S2 increased only slightly (1.7-fold) in human skin fibroblasts; while no effect was noticed in sclera fibroblasts. The expression of fibromodulin mRNA was not effected in any of the cells investigated. IL-1, PDGF and dexamethasone had no significant effects on the levels of proteoglycan and collagen mRNA, respectively. Synthesis and secretion of PG-S1, -S2 and fibromodulin wa studied by labeling with [3H]-leucine and [35S]-sulfate. Final separation of PG-S1 and -S2 was achieved by hydrophobic interaction chromatography. TGF-beta induced a 3- to 6-fold increase of [3H]- and [35S]-labeled PG-S1; while PG-S2 only increased 1.3- to 1.4-fold in both types of fibroblasts. No effect on synthesis and secretion of immunoprecipitated fibromodulin was noted.(ABSTRACT TRUNCATED AT 250 WORDS)
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| 26. |
- Willemse, Jorke, et al.
(author)
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Hydrogels derived from decellularized liver tissue support the growth and differentiation of cholangiocyte organoids
- 2022
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In: Biomaterials. - : Elsevier BV. - 0142-9612. ; 284
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Journal article (peer-reviewed)abstract
- Human cholangiocyte organoids are promising for regenerative medicine applications, such as repair of damaged bile ducts. However, organoids are typically cultured in mouse tumor-derived basement membrane extracts (BME), which is poorly defined, highly variable and limits the direct clinical applications of organoids in patients. Extracellular matrix (ECM)-derived hydrogels prepared from decellularized human or porcine livers are attractive alternative culture substrates. Here, the culture and expansion of human cholangiocyte organoids in liver ECM(LECM)-derived hydrogels is described. These hydrogels support proliferation of cholangiocyte organoids and maintain the cholangiocyte-like phenotype. The use of LECM hydrogels does not significantly alter the expression of selected genes or proteins, such as the cholangiocyte marker cytokeratin-7, and no species-specific effect is found between human or porcine LECM hydrogels. Proliferation rates of organoids cultured in LECM hydrogels are lower, but the differentiation capacity of the cholangiocyte organoids towards hepatocyte-like cells is not altered by the presence of tissue-specific ECM components. Moreover, human LECM extracts support the expansion of ICO in a dynamic culture set up without the need for laborious static culture of organoids in hydrogel domes. Liver ECM hydrogels can successfully replace tumor-derived BME and can potentially unlock the full clinical potential of human cholangiocyte organoids.
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