Navegando por Palavras-chave "Glycosaminoglycan"
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- ItemEmbargoCell-surface glycosaminoglycans regulate the cellular uptake of charged polystyrene nanoparticles(Chunli Bai, 2022-05-02) Olivieri Junior, Paulo Henrique [UNIFESP]; Jesus, Marcelo Bispo de; Nader, Helena Bonciani [UNIFESP]; Justo, Giselle Zenker; Sousa, Alioscka Augusto [UNIFESP]; http://lattes.cnpq.br/1447746283394507; http://lattes.cnpq.br/9611381402490228; http://lattes.cnpq.br/7175631659428994; http://lattes.cnpq.br/9147445236159161Engineered nanoparticles approaching the cell body will first encounter and interact with cell-surface glycosaminoglycans (GAGs) before reaching the plasma membrane and becoming internalized. However, how surface GAGs may regulate the cellular entry of nanoparticles remains poorly understood. Herein, it is shown that the surface GAGs of Chinese hamster ovary cells perform as a charge-based barrier against the cellular internalization of anionic polystyrene nanoparticles (PS NPs). In contrast, cationic PS NPs interact favorably with the surface GAGs and thereby are efficiently internalized. Anionic PS NPs eventually reaching the plasma membrane bind to scavenger receptors and are endocytosed by clathrin-mediated and lipid raft/cholesterol-dependent mechanisms, whereas cationic PS NPs are primarily internalized via clathrin-mediated endocytosis and macropinocytosis. Upon the enzymatic shedding of surface GAGs, the uptake of anionic PS NPs increases while that of cationic PS NPs is dramatically reduced. Interestingly, the diminished uptake of cationic PS NPs is observed only when heparan sulfate, but not chondroitin sulfate, is cleaved from the cell surface. Heparan sulfate therefore serves as anchors/first receptors to facilitate the cellular entry of cationic PS NPs. These findings contribute to advance the basic science of nanoparticle endocytosis while also having important implications for the use of engineered nanocarriers as intracellular drug-delivery systems.
- ItemAcesso aberto (Open Access)Collagens and proteoglycans of the corneal extracellular matrix(Associação Brasileira de Divulgação Científica, 2003-08-01) Michelacci, Yara Maria [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)The cornea is a curved and transparent structure that provides the initial focusing of a light image into the eye. It consists of a central stroma that constitutes 90% of the corneal depth, covered anteriorly with epithelium and posteriorly with endothelium. Its transparency is the result of the regular spacing of collagen fibers with remarkably uniform diameter and interfibrillar space. Corneal collagen is composed of heterotypic fibrils consisting of type I and type V collagen molecules. The cornea also contains unusually high amounts of type VI collagen, which form microfibrillar structures, FACIT collagens (XII and XIV), and other nonfibrillar collagens (XIII and XVIII). FACIT collagens and other molecules, such as leucine-rich repeat proteoglycans, play important roles in modifying the structure and function of collagen fibrils.Proteoglycans are macromolecules composed of a protein core with covalently linked glycosaminoglycan side chains. Four leucine-rich repeat proteoglycans are present in the extracellular matrix of corneal stroma: decorin, lumican, mimecan and keratocan. The first is a dermatan sulfate proteoglycan, and the other three are keratan sulfate proteoglycans. Experimental evidence indicates that the keratan sulfate proteoglycans are involved in the regulation of collagen fibril diameter, and dermatan sulfate proteoglycan participates in the control of interfibrillar spacing and in the lamellar adhesion properties of corneal collagens. Heparan sulfate proteoglycans are minor components of the cornea, and are synthesized mainly by epithelial cells. The effect of injuries on proteoglycan synthesis is discussed.
- ItemAcesso aberto (Open Access)Decorin is one of the proteoglycans expressed in Walker 256 rat mammary carcinoma(Associação Brasileira de Divulgação Científica, 2003-08-01) Oba-Shinjo, Sueli Mieko [UNIFESP]; Berto, Alessandra Gutierrez Andrade [UNIFESP]; Passerotti, Carlo Camargo [UNIFESP]; Barbosa, C.d. [UNIFESP]; Sampaio, Lucia de Oliveira [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Proteoglycan and glycosaminoglycan content was analyzed in a model of rat mammary carcinoma to study the roles of these compounds in tumorigenesis. Hyaluronic acid and proteoglycans bearing chondroitin and/or dermatan sulfate chains were detected in solid tumors obtained after subcutaneous inoculation of Walker 256 rat carcinoma cells. About 10% of sulfated glycosaminoglycan chains corresponded to heparan sulfate. The small leucine-rich proteoglycan, decorin, was identified as one of the proteoglycans, in addition to others of higher molecular weight, by cross-reaction with an antiserum raised against pig laryngeal decorin and by N-terminal amino acid sequencing. Decorin was separated from other proteoglycans by hydrophobic chromatography and its complete structure was determined. It has a molecular weight of about 85 kDa and a dermatan chain of 45 kDa with 4-sulfated disaccharides. After degradation of the glycosaminoglycan chain, three core proteins of different molecular weight (36, 46 and 56 kDa) were identified. The presence of hyaluronic acid and decorin has been reported in a variety of tumors and tumor cells. In the Walker 256 mammary carcinoma model, hyaluronic acid may play an important role in tumor progression, since it provides a more hydrated extracellular matrix. On the other hand, decorin, which is expressed by stromal cells, represents a host defense response to tumor growth.
- ItemSomente MetadadadosEffect of amniotic membrane transplantation on corneal healing and proteoglycan expression in an experimental model of limbal deficiency in rabbits(Wichtig Editore, 2010-03-01) Andrade, Alexandre L.; Campos, Mauro Silveira de Queiroz [UNIFESP]; Gomes, José Álvaro Pereira [UNIFESP]; Berto, Alessandra Gutierrez Andrade [UNIFESP]; Michelacci, Yara Maria [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Univ Estadual PaulistaPURPOSE. Amniotic membrane transplantation (AMT) has been used as a graft or as a dressing in ocular surface reconstruction, facilitating epithelization, maintaining normal epithelial phenotype, and reducing inflammation, vascularization, and scarring. The corneal transparency is due, at least in part, to the arrangement in orthogonal lamellae of collagen fibrils, surrounded by proteoglycans (PGs). These PGs regulate fibrilogenesis, the matrix assembly, and ultimately the corneal transparency. The purpose of the present study was to investigate the effects of AMT upon the corneal PGs after severe limbal injury.METHODS. Experiments were performed on the right corneas of 22 New Zealand female albino rabbits, and their left corneas were used as matched controls. These animals were divided into 3 groups: G1 (n = 10): total peritomy and keratolimbectomy, followed by application of 0.5 M NaOH; G2 (n = 10): submitted to the same trauma as G1, and treated by AMT; G3: no trauma, only AMT (n = 2). The right corneas of G2 and G3 were covered by DMSO 4 cryopreserved human amniotic membrane, fixed by interrupted 9-0 mononylon sutures, with its stromal face toward the ocular surface. After 7 or 30 days, the corneas were removed and PGs were extracted.RESULTS. Normal corneas contained approximately 9 mg of PGs per gram of dry tissue. AMT on intact cornea (G3) did not cause any changes in the concentration of PGs. In contrast, injured corneas contained much less PGs, both on the seventh and on the 30th day posttrauma. The PG concentration was even lower in injured corneas treated by AMT. This decrease was due almost exclusively to dermatan sulfate PGs, and the structure of dermatan sulfate was also modified, indicating changes in the biosynthesis patterns.CONCLUSIONS. Although beneficial effects have been observed on clinical observation and concentration of soluble proteins after AMT, the normal PG composition of cornea was not attained, even 30 days postinjury, indicating that the normal ocular surface reconstruction, if possible, is a long-term process. (Eur J Ophthalmol 2010; 20: 290-9)
- ItemAcesso aberto (Open Access)Estudo bioquímico do glicosaminoglicano dermatam sulfato em homens adultos portadores de hérnia inguinal tipo II de Nyhus(Colégio Brasileiro de Cirurgiões, 2011-06-01) Silva, Evandro de Moraes e; Lopes Filho, Gaspar de Jesus [UNIFESP]; Nader, Helena Bonciani [UNIFESP]; Gonçalves, Rogério de Oliveira [UNIFESP]; Kobayashi, Elza Yoko [UNIFESP]; Dreyfuss, Juliana Luporini [UNIFESP]; UNIFOA; Universidade Federal de São Paulo (UNIFESP)OBJECTIVE: To compare the amount of the dermatan sulfate glycosaminoglycan between male patients with Nyhus type II inguinal hernias and subjects without inguinal hernia, aged between 20 and 40 years. METHODS: Two groups were formed: One with 15 male patients with Nyhus type II inguinal hernia and aged between 20 and 40 years with ASA risk I and II, and a control group of ten individuals, also males between 20 and 40, who had died up to 24 h before. We excluded female patients, diabetic patients with connective tissue disease, smokers and surgical risk ASA III and IV. We resected a sample of 1 cm² of the transversalis fascia in the middle of the inguinal trigone, and 1 cm² of the anterior sheath of the rectus abdominis muscle in the groin for the quantification of dermatan sulfate glycosaminoglycans by densitometry after agarose gel electrophoresis. RESULTS: The amount of dermatan sulfate showed no statistically significant difference between patients with inguinal hernia and individuals without inguinal hernia in both the transverse fascia (p = 0.108) and anterior sheath of the rectus abdominis muscle (p = 0.292). CONCLUSION: There was no difference in the amount of the dermatan sulfate glycosaminoglycan among patients with Nyhus type II inguinal hernias and subjects without inguinal hernia in adult males.
- ItemSomente MetadadadosExpert recommendations for the laboratory diagnosis of MPS VI(Elsevier B.V., 2012-05-01) Wood, T.; Bodamer, O. A.; Burin, M. G.; D'Almeida, V. [UNIFESP]; Fietz, M.; Giugliani, R.; Hawley, S. M.; Hendriksz, C. J.; Hwu, W. L.; Ketteridge, D.; Lukacs, Z.; Mendelsohn, N. J.; Miller, N.; Pasquali, M.; Schenone, A.; Schoonderwoerd, K.; Winchester, B.; Harmatz, P.; Greenwood Genet Ctr; Univ Miami; Hosp Clin Porto Alegre; Universidade Federal de São Paulo (UNIFESP); Women & Childrens Hosp; Univ Fed Rio Grande do Sul; BioMarin Pharmaceut Inc; Birmingham Childrens Hosp NHS Fdn Trust; Natl Taiwan Univ Hosp; Dept Pediat; Inst Clin Chem; Childrens Hosp & Clin Minnesota; Univ Utah; Fdn Estudio Enfermedades Neurometab FESEN; Erasmus MC; UCL Inst Child Hlth; Childrens Hosp OaklandMucopolysaccharidosis VI (MPS VI) is a lysosomal storage disease caused by a deficiency of N-acetylgalactosamine 4-sulfatase (arylsulfatase B, ASB). This enzyme is required for the degradation of dermatan sulfate. in its absence, dermatan sulfate accumulates in cells and is excreted in large quantities in urine. Specific therapeutic intervention is available; however, accurate and timely diagnosis is crucial for maximal benefit. To better understand the current practices for diagnosis and to establish diagnostic guidelines, an international MPS VI laboratory diagnostics scientific summit was held in February of 2011 in Miami, Florida. the various steps in the diagnosis of MPS VI were discussed including urinary glycosaminoglycan (uGAG) analysis, enzyme activity analysis, and molecular analysis. the following conclusions were reached. Dilute urine samples pose a significant problem for uGAG analysis and MPS VI patients can be missed by quantitative uGAG testing alone as dermatan sulfate may not always be excreted in large quantities. Enzyme activity analysis is universally acknowledged as a key component of diagnosis; however, several caveats must be considered and the appropriate use of reference enzymes is essential. Molecular analysis supports enzyme activity test results and is essential for carrier testing, subsequent genetic counseling, and prenatal testing. Overall the expert panel recommends caution in the use of uGAG screening alone to rule out or confirm the diagnosis of MPS VI and acknowledges enzyme activity analysis as a critical component of diagnosis. Measurement of another sulfatase enzyme to exclude multiple sulfatase deficiency was recommended prior to the initiation of therapy. When feasible, the use of molecular testing as part of the diagnosis is encouraged. A diagnostic algorithm for MPS VI is provided. (C) 2012 Elsevier Inc. All rights reserved.
- ItemSomente MetadadadosGlycosaminoglycan chains from alpha(5)beta(1) integrin are involved in fibronectin-dependent cell migration(Canadian Science Publishing, Nrc Research Press, 2009-08-01) Franco, Celia Regina Cavichiolo [UNIFESP]; Trindade, Edvaldo da Silva [UNIFESP]; Rocha, Hugo Alexandre de Oliveira [UNIFESP]; Silveira, Rafael Bertoni da [UNIFESP]; Paludo, Katia Sabrina; Chammas, Roger; Veiga, Silvio Sanches; Nader, Helena Bonciani [UNIFESP]; Dietrich, Carl Peter [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Univ Fed Parana; Univ Fed Rio Grande do Norte; Universidade de São Paulo (USP)alpha(5)beta(1) integrin from both wild-type CHO cells (CHO-K1) and deficient in proteoglycan biosynthesis (CHO-745) is post-translationally modified by glycosaminoglycan chains. We demonstrated this using [S-35]sulfate metabolic labeling of the cells, enzymatic degradation, immunoprecipitation reaction with monoclonal antibody, fluorescence microscopy, and flow cytometry. the alpha(5)beta(1) integrin heterodimer is a hybrid proteoglycan containing both chondroitin and heparan sulfate chains. Xyloside inhibition of sulfate incorporation into alpha(5)beta(1) integrin also supports that integrin is a proteoglycan. Also. cells grown with xyloside adhered on fibronectin with no alteration in alpha(5)beta(1) integrin expression. However, haptotactic motility on fibronectin declined in cells grown with xyloside or chlorate as compared with controls. Thus, alpha(5)beta(1) integrin is a proteoglycan and the glycosaminoglycan chains of the integrin influence cell motility on fibronectin. Similar glycosylation of alpha(5)beta(1) integrin was observed in other normal and malignant cells, suggesting that this modification is conserved and important in the function of this integrin. Therefore, these glycosaminoglycan chains of alpha(5)beta(1) integrin are involved in cellular migration on fibronectin.
- ItemAcesso aberto (Open Access)Noncrystalline uric acid inhibits proteoglycan and glycosaminoglycan synthesis in distal tubular epithelial cells (MDCK)(Associação Brasileira de Divulgação Científica, 2010-10-01) Borges, Fernanda Teixeira [UNIFESP]; Dalboni, Maria Aparecida [UNIFESP]; Michelacci, Yara Maria [UNIFESP]; Schor, Nestor [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Hyperuricemia is associated with renal stones, not only consisting of uric acid (UrAc) but also of calcium oxalate (CaOx). Glycosaminoglycans (GAGs) are well-known inhibitors of growth and aggregation of CaOx crystals. We analyzed the effect of noncrystalline UrAc on GAG synthesis in tubular distal cells. MDCK (Madin-Darby canine kidney) cells were exposed to noncrystalline UrAc (80 µg/mL) for 24 h. GAGs were labeled metabolically and characterized by agarose gel electrophoresis. The expression of proteoglycans and cyclooxygenase 2 (COX-2) was assessed by real-time PCR. Necrosis, apoptosis and prostaglandin E2 (PGE2) were determined by acridine orange, HOESCHT 33346, and ELISA, respectively. CaOx crystal endocytosis was evaluated by flow cytometry. Noncrystalline UrAc significantly decreased the synthesis and secretion of heparan sulfate into the culture medium (UrAc: 2127 ± 377; control: 4447 ± 730 cpm) and decreased the expression of perlecan core protein (UrAc: 0.61 ± 0.13; control: 1.07 ± 0.16 arbitrary units), but not versican. Noncrystalline UrAc did not induce necrosis or apoptosis, but significantly increased COX-2 and PGE2 production. The effects of noncrystalline UrAc on GAG synthesis could not be attributed to inflammatory actions because lipopolysaccharide, as the positive control, did not have the same effect. CaOx was significantly endocytosed by MDCK cells, but this endocytosis was inhibited by exposure to noncrystalline UrAc (control: 674.6 ± 4.6, CaOx: 724.2 ± 4.2, and UrAc + CaOx: 688.6 ± 5.4 geometric mean), perhaps allowing interaction with CaOx crystals. Our results indicate that UrAc decreases GAG synthesis in MDCK cells and this effect could be related to the formation of UrAc and CaOx stones.
- ItemAcesso aberto (Open Access)A novel approach for the characterisation of proteoglycans and biosynthetic enzymes in a snail model(Elsevier B.V., 2011-12-01) Gesteira, Tarsis Ferreira [UNIFESP]; Coulson-Thomas, Vivien Jane [UNIFESP]; Ogata, Fernando Toshio [UNIFESP]; Farias, Eduardo Henrique Cunha de [UNIFESP]; Cavalheiro, Renan Pelluzzi [UNIFESP]; Lima, Marcelo Andrade [UNIFESP]; Cunha, Gabriel L. A [UNIFESP]; Nakayasu, Ernesto S; Almeida, Igor Correia de; Toma, Leny [UNIFESP]; Nader, Helena Bonciani [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Univ Texas El PasoProteoglycans encompass a heterogeneous group of glycoconjugates where proteins are substituted with linear, highly negatively charged glycosaminoglycan chains. Sulphated glycosaminoglycans are ubiquitous to the animal kingdom of the Eukarya domain. Information on the distribution and characterisation of proteoglycans in invertebrate tissues is limited and restricted to a few species. By the use of multidimensional protein identification technology and immunohistochemistry, this study shows for the first time the presence and tissue localisation of different proteoglycans, such as perlecan, aggrecan, and heparan sulphate proteoglycan, amongst others, in organs of the gastropoda Achatina fulica. Through a proteomic analysis of Golgi proteins and immunohistochemistry of tissue sections, we detected the machinery involved in glycosaminoglycan biosynthesis, related to polymer formation (polymerases), as well as secondary modifications (sulphation and uronic acid epimerization). Therefore, this work not only identifies both the proteoglycan core proteins and glycosaminoglycan biosynthetic enzymes in invertebrates but also provides a novel method for the study of glycosaminoglycan and proteoglycan evolution. (C) 2011 Elsevier B.V. All rights reserved.
- ItemSomente MetadadadosPapel da matriz extracelular no estímulo da síntese do heparam sulfato antitrombótico promovido pela heparina em células endoteliais(Universidade Federal de São Paulo (UNIFESP), 2004) Trindade, Edvaldo da Silva [UNIFESP]; Nader, Helena Bonciani [UNIFESP]
- ItemAcesso aberto (Open Access)Proteinase activity regulation by glycosaminoglycans(Associação Brasileira de Divulgação Científica, 2002-02-01) Tersariol, Ivarne Luis dos Santos [UNIFESP]; Pimenta, D.c. [UNIFESP]; Chagas, Jair Ribeiro [UNIFESP]; Almeida, P.c.; Universidade de Mogi das Cruzes Centro Interdisciplinar de Investigação Bioquímica; Universidade Federal de São Paulo (UNIFESP)There are few reports concerning the biological role and the mechanisms of interaction between proteinases and carbohydrates other than those involved in clotting. It has been shown that the interplay of enzymes and glycosaminoglycans is able to modulate the activity of different proteases and also to affect their structures. From the large number of proteases belonging to the well-known protease families and also the variety of carbohydrates described as widely distributed, only few events have been analyzed more deeply. The term family is used to describe a group of proteases in which every member shows an evolutionary relationship to at least one other protease. This relationship may be evident throughout the entire sequence, or at least in that part of the sequence responsible for catalytic activity. The majority of proteases belong to the serine, cysteine, aspartic or metalloprotease families. By considering the existing limited proteolysis process, in addition to the initial idea that the proteinases participate only in digestive processes, it is possible to conclude that the function of the enzymes is strictly limited to the cleavage of intended substrates since the destruction of functional proteins would result in normal tissue damage. In addition, the location as well as the eventual regulation of protease activity promoted by glycosaminoglycans can play an essential role in the development of several physiopathological conditions.