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1.
Eur J Biochem ; 268(9): 2717-24, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11322893

RESUMO

Inter-alpha-inhibitor (IalphaI) and pre-alpha-inhibitor (PalphaI) are the main members of a set of multichain serine proteinase inhibitors. Present in human plasma, they may be involved in control of the inflammatory process. They are composed of homologous heavy chains (H1 and H2 for IalphaI; H3 for PalphaI) covalently linked by a protein-glycosaminoglycan-protein cross-link to bikunin, which is a chondroitin 4-sulfate proteoglycan. During the acute-phase response, biosynthesis of IalphaI and PalphaI is downregulated and upregulated, respectively. In this work, we provide evidence that, in inflammatory diseases, the chondroitin sulfate chain of bikunin increases in size proportionally to the severity of the inflammatory response. As a consequence, all IalphaI-related components that contain bikunin are structurally modified. Therefore, the changes in glycosylation of the acute-phase proteins are not restricted to N-linked glycans but also affect glycosaminoglycans. The implications of these findings are discussed with regard to biosynthesis and biological role, especially the anti-inflammatory effects of IalphaI-related proteinase inhibitors.


Assuntos
alfa-Globulinas/química , Sulfatos de Condroitina/química , Inflamação/sangue , Glicoproteínas de Membrana/química , Inibidores de Serina Proteinase/química , Inibidor da Tripsina de Soja de Kunitz , Proteínas de Fase Aguda/química , Reação de Fase Aguda/sangue , Sulfatos de Condroitina/sangue , Glicosaminoglicanos/sangue , Glicosaminoglicanos/química , Glicosilação , Humanos , Glicoproteínas de Membrana/sangue , Peso Molecular , Polissacarídeos/sangue , Polissacarídeos/química , Inibidores de Serina Proteinase/sangue
2.
Eur J Biochem ; 268(3): 544-53, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11168393

RESUMO

The inter-alpha-inhibitor (I alpha I) family gathers together several plasma protease inhibitors such as I alpha I and pre-alpha-inhibitor (P alpha I) that are variously assembled from a set of polypeptide chain precursors designated H1P to H3P. In addition to their protease inhibitory activity, a major physiological function of I alpha I family members is hyaluronan (HA) binding and HA-dependent stabilization of the extracellular matrix surrounding various cell types. Also, binding of HA to these molecules has been shown to be an important event in tumor cell proliferation and rheumatoid arthritis. However, how HA and I alpha I family members first recognize each other has so far remained elusive. The so-called BX7B domain found in some HA-binding proteins is an HA-binding site in which B represents a basic amino-acid residue and X represents any nonacidic residue. This domain has now been identified in the N-terminal end of H3P that is a precursor of P alpha I. A series of wild-type or mutant recombinant H3P chains produced with a mouse cDNA expressed in Escherichia coli allowed us to demonstrate that this domain binds HA in a noncovalent fashion. Furthermore, unmasking this HA-binding activity required most of H3P to be trimmed off at its C-terminal end. The latter observation was confirmed with a natural, mature H3 chain purified from human plasma. Indeed, a thermolysin-generated, N-terminal fragment of this H3 chain strongly bound HA whereas the intact H3 chain did not. Therefore, in vivo, the HA-binding activity of the mature H3 chain within P alpha I may vary with the folding and/or fragmentation of this protein.


Assuntos
alfa-Globulinas/química , Ácido Hialurônico/química , Inibidores de Proteases/metabolismo , alfa-Globulinas/metabolismo , Animais , Sítios de Ligação , Divisão Celular , DNA Complementar/metabolismo , Eletroforese em Gel de Poliacrilamida , Escherichia coli/metabolismo , Glutationa Transferase/metabolismo , Humanos , Ácido Hialurônico/metabolismo , Immunoblotting , Camundongos , Modelos Genéticos , Plasmídeos/metabolismo , Reação em Cadeia da Polimerase , Ligação Proteica , Dobramento de Proteína , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes/metabolismo , Termolisina/farmacologia , Fatores de Tempo
3.
J Lab Clin Med ; 135(2): 188-98, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10695665

RESUMO

Inter-alpha-inhibitor (IalphaI) is a human plasma serine proteinase inhibitor. It contains one light peptide chain called bikunin that exerts antiproteinase activity and other antiinflammatory functions. Bikunin is covalently linked to two heavy chains that, after tissular diffusion, stabilize the extracellular matrix. Owing to its negative acute-phase reactant character and its susceptibility to proteolysis, IalphaI has been implicated in the pathophysiology of sepsis. Moreover, IalphaI has been shown to exert a protective effect on a pig model of endotoxic shock. Twenty patients admitted to the intensive care unit (ICU) for a septic syndrome were included in the present study. IalphaI and antithrombin III (ATIII) levels were measured on admission. Sequential measurements of IalphaI could be done in 4 patients. We demonstrate that IalphaI levels are significantly decreased in plasma samples collected on admission from patients with sepsis (59 +/- 32 mg/L vs 241 +/- 70 mg/L; P < .0001). This decrease was greater in severe sepsis and septic shock than in sepsis. Death was not predictable from initiol IalphaI levels. In 2 patients with a favorable course, IalphaI values regularly increased during the ICU stay. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by immunoblot analysis and microsequencing, we characterized IalphaI-related components in plasma from several patients; they obviously arise from IalphaI through proteolytic cleavage. Thus, systemic proteolysis and decreased biosynthesis both contribute to the fall in the plasma level of IalphaI. Because IalphaI is very sensitive to proteolysis by polymorphonuclear granulocytes (PMNs) that are stimulated during sepsis, we suggest that IalphaI plasma level would be a useful marker for neutrophil proteinase activity. ATIII, as well as IalphaI, is considered a negative acute phase protein. Because in vitro ATIII is less susceptible than IalphaI to proteolysis by PMNs and because their relative levels weakly correlated, we suggest that an unspecific systemic proteolysis is not significantly involved in the ATIII deficiency occurring in sepsis.


Assuntos
alfa-Globulinas/metabolismo , Bacteriemia/sangue , Inflamação/sangue , Glicoproteínas de Membrana , Sepse/sangue , Choque Séptico/sangue , Inibidor da Tripsina de Soja de Kunitz , Adulto , Idoso , alfa-Globulinas/análise , Biomarcadores/sangue , Cuidados Críticos , Endopeptidases/sangue , Feminino , Glicoproteínas/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/enzimologia , Valores de Referência , Sepse/fisiopatologia , Inibidores de Serina Proteinase/sangue , Choque Séptico/fisiopatologia
4.
Eur J Clin Invest ; 30(1): 79-86, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10620006

RESUMO

BACKGROUND: Pre-alpha-inhibitor (PalphaI) is a human plasma serine-proteinase inhibitor that is structurally related to inter-alpha-inhibitor (IalphaI). It is composed of a heavy chain named H3 covalently linked to bikunin by means of a glycosaminoglycan chain. We developed an ELISA procedure making it possible to measure PalphaI for the first time and we investigated its levels in sera from patients with inflammatory diseases. MATERIALS AND METHODS: We generated rabbit anti-H3 immunoglobulins, which were used on solid phase and biotinylated antibikunin immunoglobulins to detect trapped PalphaI. RESULTS: We demonstrate that PalphaI is more susceptible than IalphaI to in vitro proteolysis by stimulated neutrophils. However, the degradation products thus released as well as the other members of the IalphaI family present in serum do not affect the ELISA test. In a panel of control sera we observed PalphaI concentrations of 25.6 +/- 7.8 mg L-1 (mean +/- SD; n = 30). These values increased to 64.2 +/- 16.06 mg L-1 (mean +/- SD; n = 15) in patients with inflammatory diseases, concording with the positive acute-phase protein nature of PalphaI. However, for all these patients, the serum concentrations of PalphaI and C-reactive protein poorly correlated (r = 0.476; P = 0.076). Indeed, four patients had a relatively weaker increase in their PalphaI level than that of C-reactive protein. More often than not their plasma elastase content was then elevated. CONCLUSION: During inflammatory diseases plasma PalphaI levels may be dependent on increased synthesis in combination with enhanced catabolism, perhaps implicating neutrophil or other proteinases.


Assuntos
Proteínas de Fase Aguda/análise , alfa-Globulinas/metabolismo , Neutrófilos/metabolismo , Precursores de Proteínas/sangue , Inibidores da Tripsina/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Coelhos
5.
Clin Chem Lab Med ; 37(5): 521-5, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10418742

RESUMO

Human inter-alpha-inhibitor (IalphaI) has been shown to exert a beneficial therapeutic effect in a porcine model of endotoxin shock. It is therefore useful to have a better understanding of IalphaI metabolism during severe inflammatory syndromes. Experimental bacterial pneumonia was induced in pigs. The acute phase response was highlighted by an increase in pig major acute phase protein (pig-MAP) and haptoglobin concentrations in plasma collected daily over 4 days. In the same samples, the IalphaI levels remained unchanged. Moreover, crossed-immunoelectrophoretic and immunoblot analyses did not show any qualitative modification of IalphaI throughout the experiment. IalphaI has been reported to be a negative acute phase protein in both humans and rats. Here we demonstrated that IalphaI behavior clearly differs in humans and pigs and is definitively species specific.


Assuntos
Proteínas de Fase Aguda/análise , Reação de Fase Aguda/sangue , alfa-Globulinas/análise , Inibidores de Serina Proteinase/sangue , Inibidores da Tripsina/sangue , Animais , Quimotripsina/antagonistas & inibidores , Eletroforese em Gel de Poliacrilamida , Imunoeletroforese Bidimensional , Coelhos , Ratos , Suínos
6.
Eur J Biochem ; 255(1): 107-15, 1998 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-9692908

RESUMO

Human inter-alpha-inhibitor (IalphaI) is a plasma serine-proteinase inhibitor. It consists of three polypeptide chains covalently linked by a glycosaminoglycan: a light one named bikunin, carrying the antiproteinase activity and two heavy chains H1 and H2. The amino acid sequences of these heavy chains are highly similar; however when IalphaI is digested by neutrophil proteinases, their proteolytic susceptibility strongly differs [Balduyck, M., Piva, F., Mizon, C., Maes, P., Malki, N., Gressier, B., Michalski, C. & Mizon, J. (1993) Human leucocyte elastase (HLE) preferentially cleaves the heavy chain H2 of inter-alpha-trypsin inhibitor (ITI), Biol. Chem. Hoppe-Seyler 374, 895-901]. We mapped the disulphide topology of the IalphaI heavy chains in order to investigate whether or not disulphide bonds might be responsible for their differential susceptibility to proteolysis. Using amino acid sequencing and mass spectrometry analysis, we demonstrate that the H1 heavy chain contains one free thiol group and two disulphide bridges of which one links two largely spaced cysteine residues (Cys239 and Cys511). Thus H1 is clearly different from H2 which contains two disulphide bonds between closely located cysteine residues. However, using immunoprint analysis, we show that, when IalphaI is subjected to a limited digestion by Staphylococcus aureus V-8 proteinase, the two polypeptide chains are similarly susceptible to proteolysis. This enzyme preferentially cleaves the IalphaI heavy chains from their N-terminal extremity. These results are consistent with the circular dichroism (CD) analysis, suggesting that the conformation of the polypeptide backbone of H1 is not very different from that of H2, with calculated alpha-helicities of 24% and 28%, respectively. The CD measurements reveal that the aromatic amino acids of H1 and H2 are in a different asymmetrical environment. Inside the IalphaI molecule, the heavy chains are linked to the glycosaminoglycan chain via their C-terminal aspartic acid residue. Thus we suggest that the affinity of cationic neutrophil proteinases for the anionic glycosaminoglycan is responsible for the cleavage of the heavy chains (mainly H2) near their C-terminal end and the high susceptibility of IalphaI to these proteinases.


Assuntos
alfa-Globulinas/química , Proteínas Sanguíneas/química , Dissulfetos/química , Endopeptidases/metabolismo , Inibidores de Serina Proteinase/química , alfa-Globulinas/metabolismo , Sequência de Aminoácidos , Proteínas Sanguíneas/metabolismo , Catepsina G , Catepsinas/metabolismo , Dicroísmo Circular , Brometo de Cianogênio , Dissulfetos/metabolismo , Humanos , Elastase de Leucócito/metabolismo , Metaloendopeptidases/metabolismo , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Análise de Sequência , Serina Endopeptidases/metabolismo , Inibidores de Serina Proteinase/metabolismo
7.
Biochem J ; 333 ( Pt 3): 749-56, 1998 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9677337

RESUMO

Human inter-alpha-inhibitor (IalphaI) is a plasma serine-proteinase inhibitor. It consists of three polypeptide chains covalently linked by a glycosaminoglycan chain: a light chain named bikunin carrying the anti-proteinase activity and two heavy chains, H1 and H2, which exhibit specific properties, e.g. they interact with hyaluronan thus stabilizing the extracellular matrix. In this study, using matrix-assisted laser desorption ionization-time-of-flight MS and amino acid sequencing of tryptic peptides, we provide a detailed analysis of the glycosylation pattern of both heavy chains. H1 carries two complex-type N-glycans of predominantly biantennary structure linked to asparagine residues at positions 256 and 559 respectively. In contrast, the oligosaccharides attached to H2 are a complex-type N-glycan in the N-terminal region of the protein (Asn64) and three to four type-1 core-structure O-glycans mono- or di-sialylated, clustered in the C-terminal region. We propose that these O-glycans might function as a recognition signal for the H2 heavy chain. The biological implications of this hypothesis, notably for the biosynthetic pathway of IalphaI, are discussed.


Assuntos
alfa-Globulinas/metabolismo , Inibidores de Serina Proteinase/metabolismo , alfa-Globulinas/química , Sequência de Aminoácidos , Sequência de Carboidratos , Cromatografia Líquida de Alta Pressão , Glicopeptídeos/química , Glicopeptídeos/metabolismo , Glicosilação , Humanos , Substâncias Macromoleculares , Dados de Sequência Molecular , Inibidores de Serina Proteinase/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
8.
Clin Chem Lab Med ; 36(2): 111-3, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9594049

RESUMO

Urinary trans,trans-muconic acid is a sensitive biomarker for low level benzene exposure. The method described by Ducos et al. (Int Arch Occup Environ Health 1990; 62:529-34) is commonly used for its determination. In this study, we demonstrate that N-benzoyl, L-glutamic acid added to urine samples is a suitable internal standard to control trans,trans-muconic acid recovery after solid phase extraction of urine and to compensate for variations which might occur during high-performance liquid chromatography analysis.


Assuntos
Benzeno , Ácido Glutâmico , Ácido Sórbico/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Padrões de Referência , Ácido Sórbico/análise , Urinálise/métodos
9.
Am J Respir Crit Care Med ; 156(6): 1825-33, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9412562

RESUMO

We investigated the effects of human inter-alpha-inhibitor (I alpha I) on hemodynamics, oxygenation, and coagulation parameters in a porcine model of endotoxic shock. Four groups of six animals were studied: (1) control, (2) I alpha I group receiving 30 mg/kg I alpha I over 30 min, (3) LPS group receiving 5 micrograms.kg/min Escherichia coli endotoxin over 30 min, and (4) LPS + I alpha I group receiving 30 min after endotoxin 30 mg/kg/30 min I alpha I. We measured hemodynamic and oxygenation parameters, usual coagulation markers and plasma levels of thrombin-antithrombin complexes, antithrombin III activity, plasminogen activator tissue type, plasminogen activator inhibitor type 1, von Willebrand factor, tumor necrosis factor-alpha, and I alpha I at baseline and at 30, 60, 90, 120, 180, 240, and 300 min. In the I alpha I group, plasma I alpha I levels reached 447 +/- 23 mg/L just after injection and 287 +/- 39 mg/L at 300 min. I alpha I half-life was 7.3 +/- 1.9 h. In the IPS + I alpha I group, I alpha I plasma levels decreased more rapidly, reaching 260 mg/L at 300 min. Compared with the LPS group, administration of I alpha I normalized the mean arterial pressure and cardiac index, improved the LPS-induced pulmonary hypertension, and resulted in the blunted increase in blood lactate and oxygen extraction ratio. A significant decrease in thrombin-antithrombin complexes and plasminogen activator inhibitor type 1 levels were observed. There was no significant difference in plasma tumor necrosis factor-alpha levels. We concluded that in this hypodynamic model of endotoxin shock, I alpha I administration resulted in a marked improvement in the hemodynamic, oxygenation, and coagulation parameters.


Assuntos
alfa-Globulinas/uso terapêutico , Coagulação Intravascular Disseminada/terapia , Inibidores de Serina Proteinase/uso terapêutico , Choque Séptico/terapia , Animais , Antitrombina III/análise , Contagem de Células Sanguíneas , Coagulação Intravascular Disseminada/sangue , Coagulação Intravascular Disseminada/complicações , Coagulação Intravascular Disseminada/fisiopatologia , Escherichia coli , Feminino , Fibrinogênio/análise , Hemodinâmica , Ácido Láctico/sangue , Lipopolissacarídeos , Oxigênio/sangue , Peptídeo Hidrolases/análise , Inibidor 1 de Ativador de Plasminogênio/análise , Tempo de Protrombina , Choque Séptico/sangue , Choque Séptico/complicações , Choque Séptico/fisiopatologia , Suínos , Ativador de Plasminogênio Tecidual/análise , Fator de Necrose Tumoral alfa/análise , Fator de von Willebrand/análise
10.
J Lab Clin Med ; 130(3): 339-47, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9341994

RESUMO

Human neutrophil proteinases have been implicated in the pathogenesis of a wide variety of inflammatory diseases. The degradation of plasma proteins such as coagulation and fibrinolysis factors has been attributed to the excessive release of elastase in septicemia and in other conditions in which heightened proteolysis occurs. Inter-alpha-inhibitor (IalphaI) is particularly sensitive to cleavage by leukocyte proteinases. For this reason, the determination of IalphaI has been proposed as a method for evaluating plasma protein proteolysis by neutrophil enzymes. In this article we provide evidence that intact residual IalphaI can be accurately quantified by enzyme-linked immunosorbent assay (ELISA) determination without interference from fragments released from IalphaI by incubation with triggered neutrophils. We demonstrate that under these conditions IalphaI was quickly and steadily proteolyzed in a cell dose-dependent manner. Alpha-1 proteinase inhibitor (alpha1PI) partially protected IalphaI; however, the proteolysis persisted when IalphaI was incubated with stimulated neutrophils in the presence of a large relative excess of alpha1PI over the amount of elastase theoretically present in cells. For the same amount of alpha1PI, serum provided a better protection than alpha1PI alone but did not completely inhibit the IalphaI degradation. Therefore, ELISA determination of IalphaI might be useful for monitoring the in vivo activity of neutrophil proteinases in systemic proteolytic states.


Assuntos
Proteínas Sanguíneas/metabolismo , Endopeptidases/metabolismo , Glicoproteínas/metabolismo , Neutrófilos/enzimologia , Biomarcadores , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Humanos , Immunoblotting , Técnicas In Vitro , Ativação de Neutrófilo , Neutrófilos/efeitos dos fármacos , Proteínas Secretadas Inibidoras de Proteinases , Inibidores de Serina Proteinase/farmacologia , alfa 1-Antitripsina/farmacologia
11.
J Chromatogr B Biomed Sci Appl ; 692(2): 281-91, 1997 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-9188816

RESUMO

Pre-alpha-inhibitor (P alpha I) is a serine proteinase inhibitor from human plasma. It comprises bikunin (BK) responsible for antiprotease activity, covalently linked to a heavy chain H3. Here we describe its isolation from a side fraction of an industrial preparation of plasma clotting factors. By using a highly specific polyclonal antiserum prepared from rabbit immunized with a H3P polypeptide obtained in a bacterial expression system, we were able to identify the fractions containing P alpha I. Then, taking advantage of the differential affinity of the members of the inter-alpha-inhibitor family (I alpha I) for heparin-Sepharose and blue-Sepharose, we isolated P alpha I. Its specific antitryptic activity was 580 IU/g, higher than that of I alpha I: 420 IU/g. Its M(r), determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis, with or without prior reduction, was 130,000. Its peptide chains were identified by N-terminal sequencing. The H3 heavy chain was isolated from P alpha I by alkaline dissociation and anion-exchange chromatography. Its electrophoretic mobility was compared to that of the HI and H2 heavy chains of I alpha I. In reducing conditions, it was quite similar to that of H2 (M(r) 85,000) but clearly different from that of H1 (M[r] 78,000). Thus, the so-determined apparent M(r) of H3 was overestimated since its molecular mass determined by MALDI-TOF was 74,100. This result agrees with the proposed structure for H3. Indeed, by carbohydrate analysis and PNGase F digestion, we demonstrate that the two potential N-glycosylation sites present in the core-protein (theoretical mass: 69,454) are really occupied by two N-glycans, probably of biantennary type.


Assuntos
Cromatografia por Troca Iônica/métodos , Precursores de Proteínas/isolamento & purificação , Inibidores da Tripsina/isolamento & purificação , Sequência de Aminoácidos , Eletroforese em Gel de Poliacrilamida , Humanos , Estrutura Molecular , Precursores de Proteínas/sangue , Precursores de Proteínas/química , Inibidores da Tripsina/sangue , Inibidores da Tripsina/química
12.
Dig Dis Sci ; 42(4): 817-22, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9125655

RESUMO

Digestive bacterial microflora play a major role in the pathogenesis of Crohn's disease (CD). Bacterial enzyme activities, especially beta-D-galactosidase, are decreased in fecal extracts from CD patients. We hypothesized that an alteration of the colonic flora might be responsible for this decrease. Indeed, we demonstrate that beta-D-galactosidase production in supernates of anaerobic cultures was significantly (P < 0.01) reduced in feces from patients with active Crohn's disease (N = 7), when compared to healthy controls (N = 8). Therefore using X-gal and selective media, we enumerated bacteria able to release beta-D-galactosidase in feces from patients with active (N = 16) or quiescent disease (N = 5) and healthy controls (N = 14). Bifidobacteria numbers were significantly reduced in patients (P < 0.01 for active; P < 0.02 for quiescent disease) whereas Bacteroides and Lactobacilli counts remained unchanged. beta-D-Galactosidase activity and Bifidobacteria counts were significantly correlated (P < 0.03). Bifidobacteria are regarded as beneficial for the host. The reduction in Bifidobacteria is responsible for decreased beta-D-galactosidase activity. Thus oral administration of prebiotics that promote their growth might have potential therapeutic interest.


Assuntos
Bifidobacterium/isolamento & purificação , Doença de Crohn/microbiologia , Fezes/microbiologia , beta-Galactosidase/análise , Adolescente , Adulto , Bacteroides/enzimologia , Bacteroides/isolamento & purificação , Bifidobacterium/enzimologia , Contagem de Colônia Microbiana , Fezes/química , Feminino , Humanos , Lactobacillus/enzimologia , Lactobacillus/isolamento & purificação , Masculino
13.
Biochim Biophys Acta ; 1338(1): 21-30, 1997 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-9074612

RESUMO

With the view of investigating the metabolism of inter-alpha-inhibitor, a plasma serine-proteinase inhibitor, in an animal model of inflammatory syndrome, we isolated inter-alpha-inhibitor from pig plasma. A high yield was obtained (140 mg/liter) with a two-step procedure: anion-exchange chromatography followed by affinity chromatography on heparin-Sepharose. In contrast to bovine inter-alpha-inhibitor was highly similar to human inter-alpha-inhibitor: its heavy chains are homologous to the human H1 and H2 heavy chains, as shown by chromatographic and electrophoretic properties, cross-immunoreactivity and N-terminal sequencing. Pig may therefore represent a good animal model to study inter-alpha-inhibitor metabolism and elucidate its physiological role.


Assuntos
alfa-Globulinas/química , Inibidores de Serina Proteinase/química , alfa-Globulinas/isolamento & purificação , Sequência de Aminoácidos , Animais , Bovinos , Cromatografia de Afinidade , Cromatografia por Troca Iônica , Reações Cruzadas , Eletroforese em Gel de Poliacrilamida , Humanos , Hidroxilamina , Hidroxilaminas , Substâncias Macromoleculares , Camundongos , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Suínos
14.
Biochimie ; 79(12): 749-55, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9523017

RESUMO

The unrestricted activity of leukocyte proteinases is thought to contribute to the degradation of plasma proteins and thus amplify the coagulation disorders occurring in septic shock. Inter-alpha-inhibitor (I alpha I) is a plasma protein particularly susceptible to their action. Therefore we investigated its behavior in a porcine model of endotoxin shock which reproduces the coagulation changes observed in human sepsis. We did not detect any qualitative or quantitative modification of porcine I alpha I in plasmas collected from pigs after endotoxin infusion. To explain these data, I alpha I was incubated with polymorphonuclear neutrophils (PMN) stimulated by FMLP in the presence of cytochalasin B. We found that, unlike human PMN, porcine cells were unable to proteolyze I alpha I. Moreover, in the incubation medium of pig PMN, triggered either by FMLP or PMA, no measurable elastase activity was evidenced. Therefore, we urge to better take into account species differences in functional responses of PMN, to explain the experimental results obtained in animal models of septic shock.


Assuntos
alfa-Globulinas/metabolismo , Coagulação Intravascular Disseminada/sangue , Endotoxinas/administração & dosagem , alfa-Globulinas/efeitos dos fármacos , alfa-Globulinas/imunologia , Animais , Modelos Animais de Doenças , Coagulação Intravascular Disseminada/etiologia , Feminino , Humanos , Infusões Intravenosas , Ativação de Neutrófilo/efeitos dos fármacos , Neutrófilos/enzimologia , Elastase Pancreática/sangue , Suínos
15.
J Immunol Methods ; 190(1): 61-70, 1996 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-8601712

RESUMO

Inter-alpha-trypsin inhibitor (ITI) is a serine-proteinase inhibitor of human plasma enzymes. ITI is composed of three polypeptide chains covalently linked: bikunin, responsible for the antiprotease activity and two heavy chains H1 and H2. Human plasma also contains other components immunologically related to ITI such as pre-alpha-trypsin inhibitor (paI), inter-alpha-like inhibitor (IalphaLI) and free bikunin. The ELISA procedure we propose exclusively measures native ITI within the range 12.5-200 microgram/l. The intra- and interassay coefficients of variation were less than 5.6% and 8.7%, respectively. When ITI was added to plasma samples, full recovery was obtained. EDTA-plasma from 30 healthy individuals revealed a mean level of 241.5 mg/l (range 145.5-506). The high specificity, sensitivity, reproducibility and accuracy of the present assay should facilitate the specific measurement of native ITI in blood and thus might represent a useful tool for further physiopathological studies.


Assuntos
alfa-Globulinas/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Inibidores de Proteases/sangue , alfa-Globulinas/análise , Especificidade de Anticorpos , Humanos , Inibidores de Proteases/imunologia
16.
Eur J Biochem ; 236(3): 984-90, 1996 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8665922

RESUMO

Uronic-acid-rich protein (UAP) is a urinary glycoprotein that inhibits calcium oxalate crystallization in vitro. It shows a structural similarity to bikunin, a component of inter-alpha-inhibitor (IalphaI) known for its inhibition of the action of many serine proteinases like trypsin and chymotrypsin. To clarify the relationship between these macromolecules, UAP, IalphaI, urinary bikunin, and plasma bikunin were purified and studied. Their calcium oxalate crystallization inhibitory activity was assayed before and after treatment with chondroitinase AC and pronase. Their molecular mass was determined by using SDS/PAGE before and after these treatments. Polyclonal bikunin antibody was used on Western blots for immunological identification. The partial amino acid sequence of UAP before and after chondroitinase treatment was determined. Also, the antitryptic activity of UAP was measured and compared to that of bikunin, which is responsible for the antiprotease activity of IalphaI. UAP exhibited a strong calcium oxalate crystallization inhibitory activity. IalphaI and both bikunins were less inhibitory. Chondroitinase AC had no effect on inhibitory activity of these proteins even when their molecular mass changed. However, after pronase treatment, the inhibitory activity of both bikunins and UAP was completely destroyed. The antitryptic activity of UAP was found to be 0.78 U/mg which is lower than that of bikunin which is about 1.9 U/mg. On Western blotting, bikunin antibody immunoreacted with UAP and both urinary and plasma bikunins. Partial amino acid sequence confirmed the identity of UAP as urinary bikunin.


Assuntos
alfa-Globulinas/urina , Glicoproteínas/urina , Glicoproteínas de Membrana , Inibidores de Proteases/urina , Inibidor da Tripsina de Soja de Kunitz , alfa-Globulinas/química , alfa-Globulinas/farmacologia , Sequência de Aminoácidos , Western Blotting , Oxalato de Cálcio , Eletroforese em Gel de Poliacrilamida , Endopeptidases/metabolismo , Glicoproteínas/química , Glicoproteínas/isolamento & purificação , Glicoproteínas/farmacologia , Humanos , Substâncias Macromoleculares , Masculino , Dados de Sequência Molecular , Peso Molecular , Homologia de Sequência de Aminoácidos , Inibidores da Tripsina/urina
17.
Rev Med Interne ; 17(7): 576-8, 1996.
Artigo em Francês | MEDLINE | ID: mdl-8881385

RESUMO

A 33 year-old man was twice admitted in psychiatry for a non typical depression. He was later hospitalized for a convulsive seizure. Then, the discovery of dementia, neurologic trouble, positivity of syphilitic reaction in blood and in cerebro-spinal fluid allowed to diagnose general paralysis. General paralysis is a late complication of syphilis and it has become exceptional because of efficacy of detection and treatment of early state of syphilis. Now, most of cases affects AIDS patients. Nevertheless, this case shows that realisation of syphilitic reaction is always justified by any dementia or any non typical depression.


Assuntos
Neurossífilis/diagnóstico , Adulto , Demência/etiologia , Transtorno Depressivo/etiologia , Humanos , Masculino , Convulsões/etiologia
18.
Scanning Microsc ; 10(2): 425-33; discussion 433-4, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9813621

RESUMO

Inter-alpha-inhibitor (I alpha I) is a serine protease inhibitor present in human plasma. It has a molecular weight of about 220 kDa which encompasses 3 chains including two heavy chains and one light chain. The light chain, known as bikunin, is responsible for the antitryptic activity of I alpha I in the inhibition of various enzymes, such as trypsin and chymotrypsin. Under physiologic or certain pathologic circumstances, several macromolecules related to I alpha I appear in plasma and urine. However, the physiologic role of I alpha I remains unclear. As far as urolithiasis is concerned, two urinary macromolecules related to I alpha I have been isolated and shown to be potent inhibitors of calcium oxalate formation. One of these inhibitors, uronic-acid-rich protein (UAP), has been identified and well characterized. The sequence of the first 18 amino acid residues of UAP is identical with that of bikunin. Furthermore, the immunoreaction between UAP and I alpha I antibody using immunoblot analysis was positive. UAP isolated from the urine of stone formers exhibited less inhibitory activity towards calcium oxalate crystallization than that derived from the urine of healthy subjects. This suggests a structural abnormality of the inhibitor obtained from stone patients. The organic matrix extracted from kidney stones contained a protein antigenically related to I alpha I. We conclude that UAP is a member of I alpha I family taking part in inhibiting calcium oxalate crystallization, and modulating the formation of stones in the urinary tract.


Assuntos
alfa-Globulinas/fisiologia , Oxalato de Cálcio/química , Glicoproteínas de Membrana , Inibidores de Serina Proteinase/fisiologia , Inibidor da Tripsina de Soja de Kunitz , Cálculos Urinários/prevenção & controle , alfa-Globulinas/análise , Cristalização , Glicoproteínas/fisiologia , Humanos , Cálculos Urinários/metabolismo
19.
Dig Dis Sci ; 40(12): 2641-6, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8536525

RESUMO

Enzymes produced by colonic microflora have been proposed for triggering local delivery of antiinflammatory azo-bond drugs and prodrugs to the colon. This approach could be advantageous in steroid treatment of inflammatory bowel diseases, thus sparing steroids' side effects. We recently demonstrated that the metabolic activity of digestive flora, assessed on the activity of fecal glycosidases, was decreased in patients with active Crohn's disease. In the present study, the azoreductase activity in feces of 14 patients with active Crohn's disease was decreased (11.39 +/- 7.93 mU/g F) as compared with 12 healthy subjects (51.13 +/- 21.39 mU/g F). beta-D-Glucosidase and beta-D-glucuronidase activities in fecal homogenates incubated under anaerobic conditions were also decreased in patients. These data bring into question the therapeutic usefulness for those patients of azo-bond drugs and glycoside prodrugs. They could explain the therapeutic failure of some of those drugs in active ileocolic and colic Crohn's disease.


Assuntos
Colo/enzimologia , Colo/microbiologia , Doença de Crohn/enzimologia , Glucuronidase/metabolismo , NADH NADPH Oxirredutases/metabolismo , beta-Glucosidase/metabolismo , Adulto , Estudos de Casos e Controles , Doença de Crohn/tratamento farmacológico , Doença de Crohn/microbiologia , Fezes/enzimologia , Feminino , Humanos , Masculino , Nitrorredutases , beta-Galactosidase/metabolismo
20.
Therapie ; 50(5): 451-4, 1995.
Artigo em Francês | MEDLINE | ID: mdl-8571284

RESUMO

Veralipride is a substituted benzamide which is used for the treatment of menopausal hot flushes. We report five cases with extrapyramidal disorders associated to a treatment with this drug for which the neuroleptic activity resulting from an interaction with D2 receptors is not always known by prescribers. One case consisted of acute dyskinesias and four of parkinsonian syndromes, one of these being associated with tardive dyskinesia. In these four cases, dosing recommendations were not respected.


Assuntos
Antidepressivos de Segunda Geração/efeitos adversos , Discinesia Induzida por Medicamentos/etiologia , Doença de Parkinson Secundária/induzido quimicamente , Sulpirida/análogos & derivados , Doença Aguda , Idoso , Antidepressivos de Segunda Geração/uso terapêutico , Feminino , Rubor/tratamento farmacológico , Humanos , Pessoa de Meia-Idade , Sulpirida/efeitos adversos , Sulpirida/uso terapêutico
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