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Biomedical subjects

C Mizon

Publications and source records attributed to C Mizon.

At least 37 records · Page 2Linked to original sources
PubMed1992

Decreased faecal exoglycosidase activities identify a subset of patients with active Crohn's disease.

1. alpha 1-Proteinase inhibitor (alpha 1-antitrypsin) is excreted in a deglycosylated form (M(r) 38,000) in the faeces of healthy subjects and in patients with quiescent Crohn's disease. By contrast, in most patients with active Crohn's disease, alpha 1-proteinase inhibitor is excreted in a glycosylated form (M(r) 51,000). 2. Faecal extracts containing deglycosylated alpha 1-proteinase inhibitor are able to deglycosylate alpha 1-proteinase inhibitor by an exoglycosidic process. Conversely, we demonstrate that in faecal extracts from patients excreting glycosylated alpha 1-proteinase inhibitor, glycosidase activities, such as N-acetyl-beta-glucosaminidase (EC 3.2.1.30), alpha-mannosidase (EC 3.2.1.24) and particularly beta-galactosidase (EC 3.2.1.23), are strongly decreased. 3. Degradation of glycosidases by proteases could not explain the decreased glycosidase activity in these faecal extracts. 4. Our data suggest that a modification of the bacterial colonic flora (or of its metabolic activity) occurs in most patients with active Crohn's disease and could be responsible for an impaired colonic salvage of carbohydrates.

Acetylglucosaminidase↗
PubMed1992

A simple method for the measurement of different forms of alpha 1 proteinase inhibitor in the faeces of patients with Crohn's disease.

Alpha-1 proteinase inhibitor (alpha 1PI), formerly named alpha 1-antitrypsin, is excreted in the faeces of patients with Crohn's disease as isoforms clearly separated by SDS-PAGE and immunoblot analysis. Relapses in Crohn's disease are generally associated with the appearance in faeces of M(rs) 51,000 and 45,000 glycosylated forms of alpha 1PI, as compared with normal subjects and most of the patients in quiescent phases of their disease who excrete an M(r) 38,000 unglycosylated form of alpha 1PI. We used their differential Concanavalin-A reactivity to design a specific test. The proposed assay is potentially helpful for the follow-up of patients under therapy and for early recognition of attacks of Crohn's disease.

Crohn Disease↗
PubMed1992

The heavy chains of human plasma inter-alpha-trypsin inhibitor: their isolation, their identification by electrophoresis and partial sequencing. Differential reactivity with concanavalin A.

Inter-alpha-trypsin inhibitor (ITI) is a complex protein made up of a light chain so-called bikunin and two heavy chains (apparent Mr values 96000 and 86000 in SDS/PAGE in non-reducing conditions). By sequence analysis, we clearly identified those two components as H1 and H2, respectively. We demonstrate that alkaline treatment (50mM NaOH during 5 min at room temperature) as well as chondroitinase digestion both lead to the dissociation of ITI. The conditions used for alkaline treatment were previously reported for cleavage of the covalent linkage between bikunin and H3 inside pre-alpha-trypsin inhibitor (Enghild et al. (1991) J. Biol. Chem. 266, 747-751). Carbohydrate analysis of the two heavy chains isolated by ion-exchange chromatography suggests the presence of complex-type N-glycans in both H1 and H2 and that of O-glycans in H2. H1 is eluted from Con-A Sepharose by alpha-methylmannoside, in agreement with the existence of at least one biantennary glycan chain. In contrast, H2 remains strongly bound to this support when submitted to the same conditions. Therefore this binding does not depend on carbohydrates. The capacity of H2 to develop such interactions is discussed with regard to the unusual bindings likely to exist between the different peptide chains constituting ITI.

Alpha-Globulins↗
PubMed1991

A chondroitin-sulfate chain is located on serine-10 of the urinary trypsin inhibitor.

1. The glycopeptide carrying the glycosaminoglycan chain of the urinary trypsin inhibitor (immunologically and structurally related to inter-alpha-trypsin inhibitor) was isolated. 2. The data from amino acid composition and part sequencing of this glycopeptide unambiguously demonstrate that the glycosaminoglycan is covalently linked to serine-10 of the peptide chain of UTI.

Amino Acid Sequence↗
PubMed1991

Deglycosylation of alpha 1-proteinase inhibitor is impaired in the faeces of patients with active inflammatory bowel disease (Crohn's disease).

1. alpha 1-Proteinase inhibitor (alpha 1-antitrypsin) was excreted in the faeces of patients with inflammatory bowel disease in different molecular forms: Mr-51,000 and Mr-45,000 forms were widely found in the stools of patients with active disease, whereas a Mr-38,000 species was frequently recovered from healthy subjects and patients with quiescent disease (Mizon, Becuwe, Balduyck et al. Clin. Chem. 1988; 34, 2268-70). 2. N-Terminal sequencing of the Mr-38,000 form of alpha 1-proteinase inhibitor, after SDS/PAGE and electrotransfer on polyvinyl difluoride membranes, showed that it differed from plasma alpha 1-proteinase inhibitor by the loss of 17 N-terminal amino acids. 3. Carbohydrate analysis of the isolated Mr-38,000 form revealed a total lack of neutral sugars. 4. In contrast, the Mr-51,000 form of alpha 1-proteinase inhibitor is glycosylated and thus could be differentiated by virtue of its reactivity with concanavalin A. The analysis of 25 faecal extracts from patients with Crohn's disease allowed us to confirm that the presence of the glycosylated form of alpha 1-proteinase inhibitor was closely related to the degree of inflammation. 5. From these data, it may be hypothesized that the hydrolytic activity of some glycosidases is greatly reduced in active Crohn's disease.

Adolescent↗
PubMed1991

Oxidative inactivation of alpha 1-proteinase inhibitor by alveolar macrophages from healthy smokers requires the presence of myeloperoxidase.

The aim of this work was to study the ability of human alveolar macrophages (AM) of 10 healthy smokers to inactivate alpha 1-proteinase inhibitor (alpha 1PI). Purified alpha 1PI was incubated for 45 min, with human alveolar macrophages before and after stimulation by phorbol myristate acetate (PMA) or opsonized zymosan. As a positive control, the same experiments were performed in parallel with blood human neutrophils (PMN). Results are expressed as percentage of inactivation of alpha 1PI as evaluated from its inhibitory activity against porcine pancreatic elastase. A strong correlation (r = 0.99) was shown when inhibitory activity of alpha 1PI was evaluated against porcine pancreatic elastase or human neutrophil elastase. Unstimulated AM (1.57 +/- 0.9%) as well as stimulated AM (PMA: 1 +/- 0.4%; zymosan: 3 +/- 0.6%) were unable to inactivate alpha 1PI. Gel electrophoresis of alpha 1PI demonstrated that AM before or after stimulation induced a slight proteolysis of alpha 1PI, whereas both cleaved and complexed alpha 1PI were found when alpha 1PI was incubated with activated PMN. Both unstimulated (22 +/- 2.6%) and activated PMN (PMA: 91.7 +/- 4.7%; zymosan: 90 +/- 5.5%) were responsible for a significant inactivation of alpha 1PI. Catalase, in contrast to superoxide dismutase, was responsible for a near complete protection of alpha 1PI inactivation by PMN. To better determine the role of PMN secretory products, especially myeloperoxidase (MPO), we also investigated the effect of zymosan-activated PMN supernatants or of purified MPO on the alpha 1PI-AM reaction. MPO assay in PMN supernatants demonstrated that activated neutrophils released significant amounts of MPO (16.8 +/- 4.1 U/ml), whereas MPO was undetectable in activated AM supernatants.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Qualitative study of fecal alpha-1-antitrypsin in patients with inflammatory digestive disease and patients with ileostomy].

Alpha-1-antitrypsin is a glycoprotein which is excreted in feces under three different forms of molecular weight 38, 45 and 51 kDa. The 45 and 38 kDa forms are the result of a partial or total removal of the carbohydrate moiety, respectively. We determined the molecular forms of fecal alpha-1-antitrypsin in 10 controls, 13 patients with protein-losing enteropathy other than inflammatory bowel disease, 70 patients with active (n = 55) (CDAI greater than 150) and inactive (n = 15) (CDAI less than 150) Crohn's disease, 14 patients with active (n = 12) and inactive (n = 2) ulcerative colitis, and 17 patients with ileostomy. Fecal 38 kDa alpha-1-antitrypsin was found in all controls, all patients with protein-losing enteropathy, in 82 percent of patients with inactive inflammatory bowel disease, and in 20 percent of patients with active inflammatory bowel disease. In contrast, the 51 kDa and 45 kDa forms were present in feces of 80 percent of patients with active inflammatory bowel disease, and in only 17 percent of patients with inactive inflammatory bowel disease. Patients with Crohn's disease and the 51 kDa form (n = 39) had significantly higher values of activity index (CDAI) and orosomucoid than patients with Crohn's disease and the 38 kDa form (n = 26) (P less than 0.01). Deglycosylated 38 kDa alpha-1-antitrypsin was never recovered in ileostomy samples. This suggests that deglycosylation of alpha-1-antitrypsin occurred in the colon and is impaired in patients with active inflammatory bowel disease.

Adolescent↗
PubMed1990

Crossed immunoelectrophoresis does not allow accurate determination of inter-alpha-trypsin inhibitor and its derivatives in plasma.

By crossed-immunoelectrophoresis (CIE) of plasma, using anti-inter-alpha-trypsin inhibitor (ITI) immunoglobulins, beside native ITI, related components are visualized as an heterogeneous peak migrating farther than ITI. The area corresponding to this peak is largely increased in case of inflammatory disease. So, quantitative CIE has been previously proposed for discrete evaluation of ITI and its derivatives. We herein present evidence that CIE does not allow a clear separation of ITI from its derivatives: in this system, they are to some extent coprecipitated. Therefore the resulting overestimation of ITI may explain the previously reported absence of inverse relation between relative contents of ITI and derivatives in case of inflammatory disorders. Our data confirm the view that ITI acts as a precursor of smaller immunologically related inhibitors.

Alpha-Globulins↗
PubMed1989

A proteoglycan related to the urinary trypsin inhibitor (UTI) links the two heavy chains of inter-alpha-trypsin inhibitor.

cDNA studies have suggested that inter-alpha-trypsin inhibitor (ITI) is a complex of several different peptide chains; the sequence of the inhibitory part of ITI is in excellent agreement with that of the urinary trypsin inhibitor (UTI). The present report demonstrates that a compound immunologically related to UTI is released by digestion with porcine pancreatic elastase or human leucocyte elastase. Since UTI has been shown to be a proteoglycan, ITI has been treated by chondroitinase. In these conditions, ITI is dissociated and gives rise to two heavy chains (78 and 85 kDa) and one light chain (26 kDa) immunologically related to UTI and which in PAGE moves close to UTIc (produced by chondroitinase treatment of UTI). We suggest that ITI is a non-covalent complex comprising two heavy chains and one light chain immunologically related to UTI and which is also a proteoglycan.

Alpha-Globulins↗
PubMed1989

[Antitrypsin activity of the urine and alpha 1 protease inhibitor].

The urinary trypsin inhibitory capacity (TIC) is mainly due to the excretion of an inhibitor which is immunologically related to inter-alpha:trypsin inhibitor (ITI). However, alpha 1 protease inhibitor (alpha 1 PI) can be found in urine of patients with proteinuria. When this one is greater than 1 g/l, the measured TIC is more or less markedly related to the amount of alpha 1 PI present in the analyzed sample. The antitryptic activity of alpha 1 PI can be ruled out by incubating urine with specific anti-alpha 1 PI immunoglobulins. An identical result is obtained by acidification of the sample prior to TIC determination. Moreover, after freezing of urine, only the antitryptic activity of alpha 1 PI is strikingly decreased. Thus, in the presence of a significant proteinuria (greater than 1 g/l), a preliminary acidification of urine allows a suitable and specific measurement of TIC due to the inhibitor immunologically related to ITI. Thus, this one is a sensitive, useful and easy test for detecting and monitoring infections.

Bacterial Infections↗
PubMed1988

Plasma proteins immunologically related to inter-alpha-trypsin inhibitor.

SDS-polyacrylamide gel electrophoresis and immunoblot were applied to analysis of plasma proteins immunologically related to inter-alpha-trypsin inhibitor (ITI). In this system, anti-ITI sera were able to identify ITI and other components with an Mr near 120 kDa which would be degradation products of ITI by limited proteolysis. An anti-UTI (urinary trypsin-inhibitor) serum could detect, beside these derivatives, two minor components (Mr values near 90 and 60 kDa). Analysis of perchloric acid supernatants of plasma samples, using the same technic, induced visualization of a new component, similar to urinary trypsin inhibitor which could not be detected by direct analysis. This one was also characterized in a higher content in pathological samples (renal failure and infectious diseases).

Alpha-Globulins↗
PubMed1988

[Clinical value of the determination of urinary antitrypsin activity].

Urinary trypsin inhibitory capacity is mainly due to the excretion of a glycoprotein which is immunologically related to the inter alpha-trypsin inhibitor and may be a proteolytic degradation product of that substance. It was tested in 133 subjects divided into 7 groups: 24 healthy controls (group A), 21 patients with bacterial infection (group B), 37 with bacterial infection under antibiotic therapy (group C), 25 with connective tissue disease (group D), 8 with infected connective tissue disease (group E), 14 with cancer (group F) and 4 with infected cancer (group G). Urinary trypsin inhibitory capacity level was very low in controls (3.32 +/- 0.8 U/g urinary creatinine), but it was dramatically increased when infection was present (149.67 +/- 23.6 U/g urinary creatinine). This test appeared to be more effective than serum C-protein measurement simultaneous carried out in the same patients. Urinary trypsin inhibitory capacity is not related to the degree of proteinuria in the urine sample, but it is increased in patients with chronic renal failure excluded from this study. Thus, its measurement is a sensitive, easy and useful test for detecting and monitoring infections. The return to its physiological value is a very good argument in favour of therapeutic effectiveness.

Bacterial Infections↗
PubMed1988

Qualitative study of fecal alpha 1-proteinase inhibitor in normal subjects and patients with Crohn's disease.

We applied sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting to analyze fecal alpha 1-proteinase inhibitor (alpha 1 PI) from healthy subjects and patients with Crohn's disease. A component with Mr 38,000 was characterized in normal fecal extracts as well as in six pathological samples. In these cases, the Crohn's disease activity index (CDAI), a clinical index of severity of the disease, was 170 (SEM 47). In contrast, alpha 1 PI of Mr 51,000 was detected in fecal extracts from eight patients with active Crohn's disease (CDAI = 287, SEM 39). We conclude that fecal alpha 1 PI can be considered a marker of intestinal disease activity.

Adolescent↗
PubMed1987

The effect of the glycosaminoglycan chain removal on some properties of the human urinary trypsin inhibitor.

The major urinary trypsin inhibitor UTI I is a proteoglycan. UTI c (Mr 26,000), produced by chrondroitin lyase digestion of UTI I, was isolated and characterized. About 90% of the glycosaminoglycan chain was removed by this treatment without proteolytic modification, as assessed by amino-acid composition and N-terminal sequence of UTI c. Its electrophoretic mobilities on alkaline and SDS-PAGE are identical with those of UTI II which occurs in urine during storage. To study the role of the glycosaminoglycan chain on the inhibitory properties of UTI I, UTI I and UTI c were compared using different proteinases as target enzymes. The inhibitory activity towards bovine trypsin and chymotrypsin as well as human granulocytic cathepsin G did not differ significantly. However, towards human granulocytic elastase, the equilibrium dissociation constant (Ki) is 5 times higher for UTI c than for UTI I. Weak inhibitory activities were measured on human plasmin, UTI c being more efficient than UTI I. The acid-stability of UTI I is not modified after chrondroitin lyase treatment. UTI I and UTI c are equally sensitive to trypsinolysis indicating that the covalently bound glycosaminoglycan chain does not play an important role for the stability of UTI I.

Cathepsin G↗
PubMed1986

The major human urinary trypsin inhibitor is a proteoglycan.

The major urinary trypsin inhibitor (Mr 44 000), isolated from human urine, contains 35% carbohydrate. In addition to N-acetylglucosamine and neutral sugars (primarily mannose and galactose), the carbohydrate moiety contains hexuronic acid and N-acetylgalactosamine and corresponds to a glycosaminoglycan. This carbohydrate chain is an integral component of the inhibitor: it does not dissociate from the inhibitor when using dissociative conditions such as sodium dodecyl sulfate, guanidinium chloride, or by increasing ionic strength or mixing with cetylpyridinium chloride. This glycosaminoglycan chain is sensitive to chondroitinase ABC or testicular hyaluronidase digestion and corresponds to slightly sulfated chondroitin 4-sulfate or 6-sulfate. After treatment by these enzymes, the urinary inhibitor has a lower molecular mass (Mr 26 000) but still inhibits trypsin.

Amino Acids↗