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1.
SAR QSAR Environ Res ; 21(5-6): 403-13, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20818579

RESUMO

The KAshinhou Tool for Ecotoxicity (KATE) system, including ecotoxicity quantitative structure-activity relationship (QSAR) models, was developed by the Japanese National Institute for Environmental Studies (NIES) using the database of aquatic toxicity results gathered by the Japanese Ministry of the Environment and the US EPA fathead minnow database. In this system chemicals can be entered according to their one-dimensional structures and classified by substructure. The QSAR equations for predicting the toxicity of a chemical compound assume a linear correlation between its log P value and its aquatic toxicity. KATE uses a structural domain called C-judgement, defined by the substructures of specified functional groups in the QSAR models. Internal validation by the leave-one-out method confirms that the QSAR equations, with r(2 )> 0.7, RMSE 5, give acceptable q(2) values. Such external validation indicates that a group of chemicals with an in-domain of KATE C-judgements exhibits a lower root mean square error (RMSE). These findings demonstrate that the KATE system has the potential to enable chemicals to be categorised as potential hazards.


Assuntos
Ecotoxicologia/métodos , Poluentes Ambientais/química , Poluentes Ambientais/toxicidade , Relação Quantitativa Estrutura-Atividade , Animais , Peixes/fisiologia , Japão , Modelos Estatísticos
2.
Nat Prod Res ; 24(15): 1403-12, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20812129

RESUMO

Water-soluble polysaccharides were isolated from the tubers of Butea superba Roxb. and Pueraria candollei Wall. Ex Benth. var. mirifica (Shaw et Suvat.) C. Niyomdham, the leaves of Centella asiatica (L.) Urb, Ocimum basilicum L., Psidium guajava and Andrographis paniculata (Burn. f.) Nees, the stems of Cymbopogon citratus (Stapf ExG), and the fruits of Psidium guajava and Scaphium scaphigerum. The immunological impacts of the polysaccharides on T-lymphocyte proliferation in vitro was investigated by flow cytometric (immunofluorescence) analysis using staphylococcal enterotoxin B (SEB) as a positive control. It was found that the polysaccharides enhanced T-lymphocyte proliferation, ranging from 4.5 to 27.0% at a concentration of 100 microg mL(-1), while the activity of SEB was 13.3%. The medicinal plants showing the highest immuno-stimulating activity were the tubers of Butea superba Roxb. The water-extracted tubers contained 60.0% (w/w) carbohydrates with 6.6% (w/w) uronic acid. The major constituent monosaccharides of the tubers were 28.2 mol% galactose, 10.5 mol% arabinose and 36.4 mol% glucose.


Assuntos
Adjuvantes Imunológicos/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Polissacarídeos/farmacologia , Adjuvantes Imunológicos/química , Butea/química , Células Cultivadas , Citometria de Fluxo , Humanos , Ocimum basilicum/química , Extratos Vegetais/química , Folhas de Planta/química , Caules de Planta/química , Polissacarídeos/química , Psidium/química , Pueraria/química
3.
J Dairy Sci ; 90(2): 541-6, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17235130

RESUMO

Bovine alpha-lactalbumin (alpha-LA), a major milk protein, exerts strong gastroprotective activity against rat experimental gastric ulcers induced by ethanol or stress. To elucidate the mechanisms underlying this activity, the influence of alpha-LA on gastric mucus metabolism was investigated in vitro and in vivo. For the in vitro study, RGM1 cells (a rat gastric epithelial cell line) were selected for observation of the direct activity of alpha-LA on gastric mucosal cells and cultured in the presence of either alpha-LA or ovalbumin (OVA), a reference protein showing no gastroprotective activity. Amounts of synthesized and secreted mucin, a major component of mucus, were determined using [3H]glucosamine as a tracer, and prostaglandin E2 (PGE2) levels in the culture medium were determined by RIA. For the in vivo study, the thickness of the mucus gel layer, a protective barrier for gastric mucosa, was evaluated histochemically in rat gastric mucosa. alpha-Lactalbumin (3 mg/mL) significantly stimulated mucin synthesis and secretion in RGM1 cells and also increased PGE2 levels in the culture medium. In contrast, OVA showed no enhancing effects under identical conditions. Neither indomethacin, a cyclo-oxygenase inhibitor, nor AH23848, a prostaglandin EP4 receptor antagonist, affected alpha-LA-induced enhancement of mucin synthesis and secretion. In vivo, oral administration of alpha-LA (300 mg/kg x 3 times/d x 7 d) increased the thickness of the mucus gel layer in rats. These results indicate that alpha-LA fortifies the mucus gel layer by stimulating mucin production and secretion in gastric mucus-producing cells, and that this enhancing effect is independent of endogenous PGE2. Comparison of the efficacy of alpha-LA with OVA suggests that the activities observed in RGM1 cells are closely related to the gastroprotective effects in rat gastric ulcer models. In conclusion, alpha-LA stimulates mucus metabolism, and this action may be responsible for its gastroprotective activity.


Assuntos
Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Lactalbumina/farmacologia , Muco/metabolismo , Animais , Bovinos , Linhagem Celular , Meios de Cultivo Condicionados/análise , Dinoprostona/análise , Mucosa Gástrica/anatomia & histologia , Glucosamina/metabolismo , Histocitoquímica , Técnicas In Vitro , Lactalbumina/administração & dosagem , Masculino , Mucinas/biossíntese , Mucinas/metabolismo , Ovalbumina/farmacologia , Ratos , Ratos Wistar , Úlcera Gástrica/prevenção & controle , Trítio
4.
Artigo em Inglês | MEDLINE | ID: mdl-11691628

RESUMO

Acharan sulfate is a glycosaminoglycan (GAG), having the structure -->4)-2-acetamido-2-deoxy-alpha-D-glucopyranose(1-->4)-2-sulfo-alpha-L-idopyranosyluronic acid (1-->, isolated from the body of the giant African snail Achatina fulica. This GAG represents 3-5% of the dry weight of this snail's soft body tissues. Frozen sections and polyester wax sections of the snail's body were stained by Alcian blue-periodic acid-Schiff's reagent (PAS) to localize acharan sulfate. Alcian blue staining indicated that GAG was mainly secreted into the outer surface of the body from internal granules. A highly mucous material was collected and treated and the acharan sulfate was recovered by ethanol and cetyl pyridinium chloride precipitation. Crude acharan sulfate was purified by DEAE-Sephacel ion-exchange chromatography. Depolymerization of intact mucus and purified acharan sulfate fractions by heparin lyase II (heparitinase I) from Flavobacterium heparinum produced an unsaturated disaccharide as a major product, establishing the repeating unit of acharan sulfate. These results demonstrate that mucus in the granule and secreted to the outside of the body is composed entirely of acharan sulfate.


Assuntos
Glicosaminoglicanos/química , Azul Alciano/farmacologia , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Corantes/farmacologia , Eletroforese em Gel de Ágar , Eletroforese em Gel de Poliacrilamida , Heparina Liase/metabolismo , Modelos Químicos , Muco/metabolismo , Poliésteres/química , Polissacarídeos/química , Conformação Proteica , Caramujos , Fatores de Tempo , Distribuição Tecidual
5.
Biochemistry ; 40(48): 14429-39, 2001 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-11724555

RESUMO

Stromal cell-derived FGF-7 binds and activates only the resident FGFR2IIIb in epithelial cells while FGF-1 and FGF-2 exhibit a broader interaction with multiple isoforms of FGFR. Here we report the structure of FGF-7 that has been solved to 3.1 A resolution by molecular replacement with the structure of a dual function chimera of FGF-7 and FGF-1 (FGF-7/1) which was resolved to 2.3 A. Comparison of the FGF-7 structure to that of FGF-1 and FGF-2 revealed the strongly conserved Calpha backbone among the three FGF polypeptides and the surface hydrophobic patch that forms the primary receptor-binding domain. In contrast, a decrease and dispersion of the positive surface charge density characterized the heparin-binding domain of FGF-7 defined by homology to that of FGF-1 and FGF-2 in complexes with heparin. A simple heparin hexasaccharide that cocrystallized with FGF-1 and FGF-2 and protected both against protease in solution failed to exhibit the same properties with FGF-7. In contrast to FGF-1 and FGF-2, protection of FGF-7 was enhanced by heparin oligosaccharides of increased length with those exhibiting a 3-O-sulfate being the most effective. Protection of FGF-7 required interaction with specifically the fraction of crude heparin retained on antithrombin affinity columns. Conversely, heparin enriched by affinity for immobilized FGF-7 exhibited anti-factor Xa activity similar to that purified on an antithrombin affinity matrix. In contrast, an FGF-1 affinity matrix enriched the fraction of crude heparin with low anti-factor Xa activity. The results provide a structural basis to suggest that the unique FGF-7 heparin-binding (HB) domain underlies a specific restriction in respect to composition and length of the heparan sulfate motif that may impact specificity of localization, stability, and trafficking of FGF-7 in the microenvironment, and formation and activation of the FGFR2IIIb kinase signaling complex in epithelial cells.


Assuntos
Fator 1 de Crescimento de Fibroblastos/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Heparitina Sulfato/metabolismo , Sequência de Aminoácidos , Cristalização , Fator Xa/imunologia , Fator Xa/metabolismo , Fator 1 de Crescimento de Fibroblastos/química , Fator 2 de Crescimento de Fibroblastos/química , Fator 7 de Crescimento de Fibroblastos , Fatores de Crescimento de Fibroblastos/química , Heparina/farmacologia , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Relação Estrutura-Atividade
6.
J Lipid Res ; 42(10): 1604-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11590216

RESUMO

A variety of procedures have been developed for determining the sulfate ester content of various biomolecules. Ion chromatography (IC), that is, quantitation of ionic substances by ion conductimetry after separation by anion-exchange chromatography, has been increasingly utilized for the determination of inorganic sulfate in clinical and environmental samples. We adopted suppressed-mode IC to the determination of lipid- or glycolipid-bound sulfate released by acid hydrolysis and found that it has the advantage of increased precision for wide concentration ranges (30 pmol to approximately micromol) and lack of interference from other lipids. To minimize deterioration of the separation column, the lipophilic constituents in the acid hydrolysate were removed by a two-phase partition system of chloroform-methanol-water. The inorganic sulfate was quantitatively extracted into the aqueous phase by replacing water with an alkaline buffer. By this method, the concentration of sulfolipids was determined in the kidney of mammals with various body mass. Sulfolipids were more concentrated in the kidney of smaller animals, which have higher maximum urine concentrating activity per gram of body mass, supporting the hypothesis of the function of sulfolipids as an ion barrier on the luminal surface of renal tubules.


Assuntos
Cromatografia por Troca Iônica/métodos , Rim/química , Lipídeos/análise , Animais , Gatos , Bovinos , Cromatografia Líquida de Alta Pressão , Cães , Cobaias , Lipídeos/isolamento & purificação , Camundongos , Coelhos , Ratos
7.
Toxicology ; 166(3): 119-28, 2001 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-11543908

RESUMO

Exposure to diesel exhaust (DE) induces lesions in lung epithelium by generation of reactive oxygen species. Glycosaminoglycans (GAG), components of extracellar matrix, are thought to play important roles in cell proliferation and differentiation in the repair process of injured tissue. We investigated how GAG are related to the recovery of lung tissue from injury. Using high-performance liquid chromatography analysis, we determined the amounts of GAG, such as chondroitin sulfate (CS), dermatan sulfate (DS), and hyaluronan (HA) in the lungs of rats exposed to DE for 4 weeks at concentrations of 0.3 or 3 mg/m(3) as suspended particulate matter, or to filtered air. The contents of CS and HA in the surroundings of the bronchi were significantly increased after exposure to DE. In addition, immunohistochemical staining showed that the number of 8-hydroxydeoxyguanosine-positive cells as a marker of cell damage, and proliferating cell nuclear antigen-positive cells also increased in the same areas in which the levels of GAG were elevated in the lungs of rats exposed to 3 mg/m(3) DE. These results suggest that CS and HA in the lung contribute to cell proliferation and remodeling in the process of recovery from injury caused by exposure to DE.


Assuntos
Pulmão/efeitos dos fármacos , Emissões de Veículos/toxicidade , 8-Hidroxi-2'-Desoxiguanosina , Administração por Inalação , Animais , Brônquios/química , Brônquios/efeitos dos fármacos , Brônquios/metabolismo , Brônquios/patologia , Contagem de Células , Sobrevivência Celular/efeitos dos fármacos , Sulfatos de Condroitina/análise , Sulfatos de Condroitina/metabolismo , Cromatografia Líquida de Alta Pressão , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Dermatan Sulfato/análise , Dermatan Sulfato/metabolismo , Relação Dose-Resposta a Droga , Células Epiteliais/química , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Técnica Indireta de Fluorescência para Anticorpo , Ácido Hialurônico/análise , Ácido Hialurônico/metabolismo , Pulmão/química , Pulmão/metabolismo , Pulmão/patologia , Macrófagos Alveolares/química , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/patologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Pleura/química , Pleura/efeitos dos fármacos , Pleura/metabolismo , Pleura/patologia , Antígeno Nuclear de Célula em Proliferação/análise , Ratos , Ratos Sprague-Dawley
8.
Anal Biochem ; 297(1): 42-51, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11567526

RESUMO

(1)H NMR spectroscopy has been established for the determination of uronate residues in glycosaminoglycans (GAGs) such as dermatan sulfate (DS), heparin (HP), and heparan sulfate (HS). Because of variation in the sulfonation positions in DS, HP, or HS, interpretation of spectra is difficult. Solvolysis was applied to remove O-sulfo groups from these GAG chains in dimethyl sulfoxide containing 10% methanol at 80 degrees C for 5 h. In the cases of HP and HS, N-sulfo groups on glucosamine residues were also removed under the same conditions. The resulting unsubstituted amino groups in HP and HS chains were re-N-acetylated using acetic anhydride to obtain homogeneous core structure with the exception of the variation of uronate residues. The contents of glucuronate and iduronate residues in the chemically modified DS, HP, and HS samples were analyzed by 600-MHz (1)H NMR spectroscopy. These methods were applied to compositional analysis of uronate residues in GAGs isolated from various sources.


Assuntos
Dermatan Sulfato/química , Ácido Glucurônico/análise , Heparina/química , Heparitina Sulfato/química , Ácido Idurônico/análise , Espectroscopia de Ressonância Magnética/métodos , Animais , Cromatografia Gasosa , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Dissacarídeos/análise , Dissacarídeos/química , Epiderme/química , Ácido Glucurônico/química , Ácido Idurônico/química , Mucosa Intestinal/química , Suínos
9.
Biochemistry ; 40(38): 11518-24, 2001 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-11560500

RESUMO

Circumsporozoite (CS) protein is a predominant surface antigen of malaria sporozoites, the infective form of the parasite, and has been used for making anti-malaria vaccines. For the first time we have examined the interaction of CS protein with various glycosaminoglycans in real time using surface plasmon resonance (SPR) and isothermal titration calorimetry (ITC). Heparin was the best binder among the glycosaminoglycans tested and bound to CS protein with nanomolar affinity. Using purified and structurally defined small heparin oligosaccharides, we identified a decasaccharide to be the minimum sized CS protein-binding sequence. In an indirect competition assay, this decasaccharide blocked the CS protein interaction with HepG2 cells with an ID(50) of less than 60 nM. The decasaccharide has a structure commonly found in hepatic heparan sulfate, and the same sequence has recently been shown to bind specifically to apolipoprotein E. Examination of porcine liver heparan sulfate in this indirect competition assay showed that it and heparin were the only glycosaminoglycans that could effectively block CS protein interaction with HepG2 cells in culture. These data support the hypothesis that the invasion of liver cells by the parasite shares a common mechanism with the hepatic uptake of lipoprotein remnants from the blood.


Assuntos
Glicosaminoglicanos/química , Heparina/química , Oligossacarídeos/química , Proteínas de Protozoários/química , Animais , Configuração de Carboidratos , Sequência de Carboidratos , Dissacarídeos/química , Glicosaminoglicanos/metabolismo , Heparina/metabolismo , Oligossacarídeos/metabolismo , Plasmodium , Proteínas de Protozoários/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Suínos
10.
J Chromatogr A ; 922(1-2): 365-9, 2001 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-11486884

RESUMO

Centrifugal precipitation chromatography (CPC) was applied for the first time to the separation of fragments of chondroitin sulfate (ChS) and hyaluronic acid (HA). The separation was performed using a gradient elution system between ethanol and water since solubility of these biopolymers highly depends on the concentration of ethanol in aqueous solution. ChS and HA were each eluted into several peaks through a flow-through UV detector at 275 nm, despite they have almost no absorbance at this wavelength in an aqueous solution. The separation was also confirmed by redissolving the dried fraction in water and measuring the absorbance at 210 nm. These results suggest that the CPC system can detect small precipitates of these biopolymers by light scattering at 275 nm. The separated fragments of biopolymers are not easily characterized because no suitable analytical method is available for identification of these compounds. However, the overall results demonstrate that CPC may be a useful separation of biopolymers such as glycosaminoglycans which quantitatively produce precipitates in an organic solvent mixture.


Assuntos
Sulfatos de Condroitina/isolamento & purificação , Cromatografia Líquida/métodos , Ácido Hialurônico/isolamento & purificação , Centrifugação , Precipitação Química , Espectroscopia de Ressonância Magnética , Espectrofotometria Ultravioleta
11.
J Nutr ; 131(8): 2121-7, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11481405

RESUMO

Pharmaceutical and food-related applications of lactoferrin, an 80-kDa iron-binding glycoprotein found predominantly in milk, have attracted interest lately, but the process of digestion of lactoferrin has been poorly characterized. The digestive fate of bovine lactoferrin in adult rats after oral administration of a single dose and after dietary supplementation was studied by (125)I-labeling and by surface-enhanced laser desorption/ionization (SELDI) affinity mass spectrometry. The latter method was designed to detect multiple forms of degraded lactoferrin as simple molecular ion peaks corresponding to one of the core regions of lactoferrin, namely, the lactoferricin region (Phe17-Ala42). Radioactive fragments with molecular masses of 42, 36, 33 and 29 kDa were observed at 20, 60 and 180 min postingestion in the contents of the lower small intestine. Rats were given free access to milk enriched with lactoferrin at 482 micromol/L (40 mg/mL). The concentrations of lactoferrin fragments in the contents of the stomach, small intestine and lower small intestine as determined by SELDI affinity mass spectrometry were approximately 200, 20 and 1 micromol/L, respectively. These data indicate that functional fragments of LF such as fragments containing glycosaminoglycan-binding site(s), as well as large fragments with a mass >20 kDa, indeed survive proteolytic degradation in the small intestine of adult rats.


Assuntos
Trânsito Gastrointestinal , Intestino Delgado/metabolismo , Lactoferrina/metabolismo , Fragmentos de Peptídeos/metabolismo , Administração Oral , Animais , Digestão , Isótopos de Iodo , Cinética , Lactoferrina/administração & dosagem , Masculino , Leite/química , Peso Molecular , Ratos , Ratos Endogâmicos F344 , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
12.
Biomed Chromatogr ; 15(5): 356-62, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11507718

RESUMO

We established a highly sensitive quantitative analytical method for chondroitin/dermatan sulfates by LC/MS method. By this method, the unsaturated disaccharides produced after the enzymatic digestion of chondroitin/dermatan sulfates can be determined in the amounts as low as 0.5 pmol levels. The use of tetrabutylammonium hydroxide as an ion-pair reagent for LC/MS allowed us to separate unsaturated 4-sulfated disaccharide and unsaturated 6-sulfated disaccharide. Furthermore, the peak areas of unsaturated disaccharides were increased almost 10 times by the postcolumn addition of acetonitrile. We applied this LC/MS method to the analyses of unsaturated disaccharides from chondroitin/dermatan sulfates in the tissues sections on glass slides, which were prepared from MethA tumor-bearing mice. This method brought about considerable reduction in the time distance from sample collection to preparation of analytical results.


Assuntos
Sulfatos de Condroitina/análise , Cromatografia Líquida de Alta Pressão/métodos , Dermatan Sulfato/análise , Espectrometria de Massas/métodos , Neoplasias/química , Neoplasias/patologia , Reprodutibilidade dos Testes
13.
Biosci Biotechnol Biochem ; 65(5): 1104-11, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11440124

RESUMO

Although several studies have shown that milk protein components have a wide range of biological activities, the potential role of these proteins in the gastrointestinal mucosal defense system is less well elucidated. In this study, we investigated the effect of the major proteins in cow's milk on gastric mucosal injury by using two acute ulcer models in Wistar rats. Gastric mucosal injury was induced by either intragastric 60% ethanol-HCl or water-immersion restraint stress (23 degrees C, 7 h). Each test milk protein was orally administered 30 min before the induction of gastric injury. Among the major milk proteins, alpha-lactalbumin (alpha-LA) is demonstrated to have a marked protective effect against ethanol-induced gastric injury, with the same potency as that of the typical antiulcer agent, Selbex. Whey protein isolate (WPI), which contained 25% alpha-LA, also protected against gastric injury, while casein showed no effect. Comparative studies on the protective effect of the four major components of WPI, beta-lactoglobulin, alpha-LA, bovine serum albumin and gamma-globulins (immunoglobulins), on the basis of their contents in WPI revealed that alpha-LA was responsible for the protective effect of WPI, being about 4-fold more effective than WPI itself. Alpha-LA showed dose-dependent protection against gastric injury induced by stress as well as ethanol. Pretreatment with indomethacin (10 mg/kg body weight, s.c.), which is a potent inhibitor of endogenous prostaglandin synthesis, resulted in a significant reduction in the protective effect of alpha-LA. These results indicate that alpha-LA has marked antiulcer activity as an active component of cow's milk protein, and suggest that alpha-LA intake may serve to protect against gastric mucosal injury, in part through endogenous prostaglandin synthesis.


Assuntos
Etanol/toxicidade , Mucosa Gástrica/fisiopatologia , Lactalbumina/metabolismo , Úlcera Gástrica/prevenção & controle , Estresse Fisiológico/fisiopatologia , Animais , Western Blotting , Bovinos , Mucosa Gástrica/efeitos dos fármacos , Masculino , Prostaglandinas/fisiologia , Ratos , Ratos Wistar , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/etiologia
14.
J Med Chem ; 44(13): 2178-87, 2001 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-11405655

RESUMO

A structure-activity relationship study was carried out to facilitate development of inhibitors of dengue virus infectivity. Previous studies demonstrated that a highly charged heparan sulfate, a heparin-like glycosaminoglycan found on the cell surface, serves as a receptor for dengue virus by binding to its envelope protein. Interventions that disrupt this binding effectively inhibit infectivity. A competitive binding assay was developed to screen polyanionic compounds for activity in preventing binding of dengue virus envelope protein to immobilized heparin; compounds tested included drugs, excipients, and larger glycosaminoglycans and their semisynthetic derivatives. Results of this competitive binding assay were used to select agents for detailed evaluation of interactions by surface plasmon resonance spectroscopy, which afforded binding on-rates, off-rates, and dissociation constants. From these data, an understanding of the structural requirements for polyanion binding to dengue virus envelope protein has been established.


Assuntos
Anticoagulantes/química , Anticoagulantes/farmacologia , Antivirais/síntese química , Vírus da Dengue/metabolismo , Glicosaminoglicanos/química , Glicosaminoglicanos/farmacologia , Heparina/química , Heparina/farmacologia , Proteínas do Envelope Viral/química , Antivirais/farmacologia , Ligação Competitiva/efeitos dos fármacos , Sequência de Carboidratos , Cromatografia Líquida de Alta Pressão , Escherichia coli/genética , Escherichia coli/metabolismo , Ácido Hialurônico/síntese química , Ácido Hialurônico/química , Cinética , Dados de Sequência Molecular , Peso Molecular , Oligossacarídeos/síntese química , Oligossacarídeos/química , Ligação Proteica , Relação Estrutura-Atividade , Sulfatos/química , Ressonância de Plasmônio de Superfície , Proteínas do Envelope Viral/antagonistas & inibidores , Proteínas do Envelope Viral/biossíntese
15.
J Chromatogr B Biomed Sci Appl ; 754(1): 153-9, 2001 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11318410

RESUMO

We established a highly sensitive quantitative analytical method of heparan sulfates (HS) by LC-MS-MS. It became possible to determine the unsaturated disaccharides produced by the enzyme digestion of HS, and to perform the whole analyses on one sample within 3 min by use of a short column of CAPCELL PAK NH2 UG80 (35 mm x 2 mm I.D.). The assay method was validated and showed the satisfactory sensitivity, precision and accuracy, which enabled the quantitation up to picomol level. By employing this method, we performed the analyses of HS in mouse brain and liver, and tumor tissues of tumor-bearing mouse transplanted subcutaneously with Meth A fibrosarcoma cells. The compositions of the unsaturated disaccharide units derived from HS were found to be somewhat different among those tissues. It is assumed that the site of sulfation in HS may be controlled by certain regulatory mechanisms. The quantitative method developed in this study is believed to be a very useful method for the determination of compositional profiles of constitutive disaccharide units of tissue HS.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Heparitina Sulfato/análise , Animais , Química Encefálica , Sequência de Carboidratos , Fígado/química , Espectrometria de Massas , Camundongos , Dados de Sequência Molecular , Neoplasias Experimentais/química , Reprodutibilidade dos Testes
16.
Glycobiology ; 11(1): 57-64, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11181562

RESUMO

Hyaluronan was partially depolymerized on a large-scale quantity using bacterial hyaluronidase (E.C. 4.2.2.1) for preparation of chemically fully O-sulfated oligosaccharides. The hyaluro-oligosaccharide (HAoligo) mixture obtained by partial digestion was repeatedly applied to low pressure gel permeation chromatographic separation to purify the size-unified oligosaccharide ranged from 4- to 20-mer. The purity and size of each HAoligo was confirmed by using proton nuclear magnetic resonance ((1)H NMR) spectroscopy, capillary electrophoresis (CE) on normal polarity mode, and a newly established separation method by normal phase chromatography with Amide-80 column. The purified HAoligos ranged 4- to 20-mer were applied to chemically fully O-sulfation. Characterization of chemically fully O-sulfated HAoligos was performed by both chemical compositional analyses after hydrolysis and (1)H NMR spectroscopy. While the anti-factor IIa activity of 4- to 20-mer O-sulfated HAoligos was less than 3.1 units/mg, the inhibitory action for hyaluronidase (bovine testicular hyaluronidase (E.C.3.2.1.35)) of the oligosaccharides ranged 16- to 20-mer were corresponding to 79% of that shown by fully O-sulfated hyaluronan (MW 100 kDa) through both competitive and noncompetitive effects.


Assuntos
Inibidores Enzimáticos/farmacologia , Ácido Hialurônico/química , Hialuronoglucosaminidase/antagonistas & inibidores , Oligossacarídeos/farmacologia , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Oligossacarídeos/química , Ácidos Sulfúricos/química
17.
Anal Biochem ; 290(1): 68-73, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11180938

RESUMO

We established a highly sensitive LC/MS/MS method for the analysis of the disaccharides produced from keratan sulfates (KS). It was revealed that the disaccharides produced by keratanase II enzymatic digestion of KS could be determined with high sensitivity by the negative-ion mode of multiple reaction monitoring. Furthermore, monosulfated and disulfated disaccharides can be separated using a short column of Capcell Pak NH2 UG80 (35 mm x 2 mm i.d.). The complete analysis of one sample can be performed within 5 min. The assay method was validated and showed satisfactory sensitivity, precision, and accuracy, which enabled quantitation at subpicomole levels. From the results of analyses of KS obtained from cornea, nasal cartilage, and brain, it was found that the degree of sulfation at the C-6 position of the galactose residues differed among those samples in the following order: nasal cartilage > cornea > brain. Our analytical method is very useful for the analyses of KS in various biological materials and for comparison of the degree of sulfation of KS from various biological samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Sulfato de Queratano/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Bovinos , Córnea/química , Dissacarídeos/análise , Proteoglicanas/análise , Controle de Qualidade , Reprodutibilidade dos Testes
18.
Glycoconj J ; 18(8): 635-40, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12376728

RESUMO

Comparison of oligosaccharide components derived from salivary mucin was performed between secretor and non-secretor individuals. Salivary mucin was collected from four secretors and three non-secretors having blood group type-A. Compositional analysis showed that the contents of galactose and N-acetylglucosamine in the non-secretor were higher than those in the secretor. The O-linked oligosaccharides obtained by treatment with alkaline borohydride were separated by gel filtration using Sephadex G-50. The results indicated that the size of the type-A active oligosaccharides from the secretor was similar to or smaller than that of the non-secretor. Ion-exchange chromatography showed that the secretors had strong type-A activities in both the neutral and acidic fractions but the non-secretors showed type-A activity mainly in the neutral fraction. These results suggest that compositional differences in blood group substances exist between secretors and non-secretors.


Assuntos
Sistema ABO de Grupos Sanguíneos , Mucinas/química , Oligossacarídeos/química , Saliva/metabolismo , Amino Açúcares/análise , Amino Açúcares/química , Cromatografia em Gel , Cromatografia por Troca Iônica , Ensaio de Imunoadsorção Enzimática , Humanos , Japão , Antígenos do Grupo Sanguíneo de Lewis , Monossacarídeos/análise , Monossacarídeos/química , Mucinas/isolamento & purificação , Oligossacarídeos/análise , Fenótipo
19.
Glycobiology ; 10(10): 1033-9, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11030749

RESUMO

Eight oligosaccharides were prepared from dermatan sulfate (DS) and their structures were elucidated. Porcine intestinal mucosal DS was subjected to controlled depolymerization using chondroitin ABC lyase (chondroitinase ABC). The oligosaccharide mixture formed was fractionated by low-pressure gel permeation chromatography (GPC). Size uniform mixtures of disaccharides, tetrasaccharides, hexasaccharides, octasaccharides, decasaccharides, and dodecasaccharides were obtained. Each size-fractionated mixture was then purified on the basis of charge by repetitive semi-preparative strong-anion-exchange (SAX) high-performance liquid chromatography (HPLC). This approach has led to the isolation of six homogeneous oligosaccharides. The size of the oligosaccharides were determined using GPC-HPLC. Treatment of tetrasaccharide and hexasaccharide fragments with Hg(OAc)2 afforded trisaccharide and pentasaccharide products, respectively. The purity of the oligosaccharides obtained was confirmed by analytical SAX-HPLC, and capillary electrophoresis (CE). The molecular mass and degree of sulfation of the eight purified oligosaccharides were elucidated using electrospray ionization (ESI) mass spectrometry and their structures were established with high field nuclear magnetic resonance (NMR) spectroscopy. These DS-oligosaccharides are currently being used to study for interaction of the DS with biologically important proteins.


Assuntos
Dermatan Sulfato/química , Oligossacarídeos/química , Animais , Condroitina ABC Liase , Cromatografia em Gel , Mucosa Intestinal/química , Mercúrio , Ressonância Magnética Nuclear Biomolecular , Espectrometria de Massas por Ionização por Electrospray , Suínos
20.
Proc Natl Acad Sci U S A ; 97(19): 10359-64, 2000 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-10984531

RESUMO

Heparin- and heparan sulfate-like glycosaminoglycans (HLGAGs) represent an important class of molecules that interact with and modulate the activity of growth factors, enzymes, and morphogens. Of the many biological functions for this class of molecules, one of its most important functions is its interaction with antithrombin III (AT-III). AT-III binding to a specific heparin pentasaccharide sequence, containing an unusual 3-O sulfate on a N-sulfated, 6-O sulfated glucosamine, increases 1,000-fold AT-III's ability to inhibit specific proteases in the coagulation cascade. In this manner, HLGAGs play an important biological and pharmacological role in the modulation of blood clotting. Recently, a sequencing methodology was developed to further structure-function relationships of this important class of molecules. This methodology combines a property-encoded nomenclature scheme to handle the large information content (properties) of HLGAGs, with matrix-assisted laser desorption ionization MS and enzymatic and chemical degradation as experimental constraints to rapidly sequence picomole quantities of HLGAG oligosaccharides. Using the above property-encoded nomenclature-matrix-assisted laser desorption ionization approach, we found that the sequence of the decasaccharide used in this study is DeltaU(2S)H(NS,6S)I(2S)H(NS, 6S)I(2S)H(NS,6S)IH(NAc,6S)GH(NS,3S,6S) (+/-DDD4-7). We confirmed our results by using integral glycan sequencing and one-dimensional proton NMR. Furthermore, we show that this approach is flexible and is able to derive sequence information on an oligosaccharide mixture. Thus, this methodology will make possible both the analysis of other unusual sequences in HLGAGs with important biological activity as well as provide the basis for the structural analysis of these pharamacologically important group of heparin/heparan sulfates.


Assuntos
Antitrombina III/metabolismo , Heparina/química , Oligossacarídeos/química , Sítios de Ligação , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Oligossacarídeos/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
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