Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.11.1.7 (peroxidase)
65,474 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The most important eosinophil-derived mediators which may contribute to the pathogenesis of asthma are: major basic protein, eosinophil cationic protein, eosinophil peroxidase, reactive oxygen species, leukotriene C4, and platelet-activating factor. The potency of the eosinophil to release these mediators can be greatly enhanced by eosinophil mobilizing and activating factors such as granulocyte macrophage colony stimulating factor, interleukins 3 and 5, platelet-activating factor, and perhaps leukotriene B4. For the development of more effective anti-asthma drugs it, therefore, seems relevant to unravel and interfere with the steps of eosinophil activation.
...
PMID:Contribution of eosinophil-derived mediators in asthma. 269 67

The presence of receptors for IgE on eosinophils has drawn attention to their direct participation in IgE-dependent hypersensitivity reactions. Surface IgE antibodies were detected on eosinophils from parasite-infected or allergic patients. The addition of the specific antigen or anti-IgE antibodies to such purified eosinophils induced the release of eosinophil peroxidase (EPO) and major basic protein (MBP), but not of eosinophil cationic protein (ECP). In contrast, ECP was detected after the addition of anti-IgG antibodies. Moreover, PAF-acether was only produced after IgE-dependent activation of hypodense eosinophils but not after IgG triggering. These results suggest a selectivity in the mediators (pre-formed and newly formed) released in response to IgE- or IgG-dependent activation of human hypodense eosinophils. Associated with preliminary findings obtained by using electron microscopy and immunogold staining, they bring new information concerning the mechanisms of release of eosinophil mediators. Finally, they underline the essential role of eosinophils in hypersensitivity reactions.
...
PMID:Eosinophils: receptors and mediators in hypersensitivity. 271 41

A skin window technique was used to study the morphology of leucocytes in upper dermis and exudate during nickel challenge in patients with contact allergy to nickel. Contact allergic patients and healthy volunteers tested with a skin widow without addition of nickel to the chamber medium served as controls. The morphology of the leucocytes in dermis was studied in biopsies taken 8, 24, or 48 h after skin window application, and in a parallel test the morphology of the exudate was examined by sequential collection of the chamber medium during a 48 h period. The infiltrate in dermis of contact allergic patients with nickel challenge in the chamber medium showed a time-dependent increase of mononuclear cells, eosinophils and basophils and a concomitant decrease of polymorphonuclear granulocytes, characteristic of a combined specific and unspecific inflammation. The morphology of the exudate in contact allergic patients exposed to nickel showed a dominance of polymorphonuclear granulocytes throughout the study period, while mononuclear cells, eosinophils and basophils were detected at a much lower quantity and with a considerable delay. Further, we studied the kinetics of the leucocyte granule proteins: lactoferrin, myeloperoxidase, lysozyme and eosinophil cationic protein in exudate fluid in a parallel test. A significant higher flux was found for all during the second day of allergen exposure compared to contact allergic patients without allergen challenge as well as normal volunteers. The increased protein fluxes were not accompanied by an increased flux of polymorphonuclear granulocytes in the exudate.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Lactoferrin, myeloperoxidase, lysozyme and eosinophil cationic protein in exudate in delayed type hypersensitivity. 283 74

Excessive ethanol intake may affect the intestinal mucosa functionally and morphologically. The ethanol effect could partly be the result of inflammatory mechanisms, possibly reflected by an enhanced local granulocyte turnover. This study investigated habitual alcoholics by segmental perfusion of the jejunum and analysed the perfusion fluid content of granulocyte granule constituents. The mean jejunal secretion rate of myeloperoxidase (MPO), a neutrophil granule constituent, was 152 (26) (SE) ng/min/40 cm jejunal segment in the controls (n = 16). The MPO secretion rate in non-cirrhotic habitual alcoholics (n = 7) was on average 450 (103) ng/min and significantly increased compared with controls (p less than 0.001). In contrast alcoholics with cirrhosis (n = 6) had normal MPO secretion rate. The mean secretion rate of eosinophil cationic protein (ECP), an eosinophil granule constituent, was in the controls 77 (15) ng/min/40 cm jejunal segment. Corresponding values in non-cirrhotic and cirrhotic alcoholics were 141 (38) and 130 (93) ng/min, respectively (ns). The data suggest an enhanced neutrophil granulocyte turnover in the jejunum in alcoholics, possibly contributing to the ethanol induced affection of the small bowel. The lack of increased neutrophil activity in cirrhotic alcoholics may reflect a role of the liver for granulocyte activity.
...
PMID:Neutrophil and eosinophil involvement of the small bowel affected by chronic alcoholism. 285 4

Bronchoalveolar lavage (BAL) was performed on eleven healthy smokers before and after eight weeks of oral treatment with N-acetylcysteine (NAC) 200 mg t.i.d. The concentrations of selected eosinophil and neutrophil granule constituents and of selected proteases and protease inhibitors, albumin and endotoxin were determined in the recovered BAL fluid and in plasma or serum samples. In addition, in vitro chemotactic activities for neutrophils and eosinophils were assessed in the BAL fluid. Significant reductions in BAL fluid content of lactoferrin (LF), eosinophil cationic protein (ECP), antichymotrypsin (ACT) and chemotactic activity for neutrophils were recorded after NAC treatment. The levels of other examined markers tended to be reduced or were not affected. In serum/plasma, the concentrations of myeloperoxidase (MPO) and elastase were reduced after NAC treatment whereas concentrations of other constituents examined were unaltered. These data, together with previously reported findings, suggest that oral NAC may influence the activity of "inflammatory" cells in the bronchoalveolar space of smokers.
...
PMID:Oral N-acetylcysteine reduces selected humoral markers of inflammatory cell activity in BAL fluid from healthy smokers: correlation to effects on cellular variables. 285 4

We tested the effects of four eosinophil granule cationic proteins: major basic protein (MBP), eosinophil cationic protein (ECP), eosinophil peroxidase (EPO), and eosinophil-derived neurotoxin (EDN), on guinea pig tracheal epithelium in vitro. Examination by inverted microscopy revealed that MBP, both the form stabilized by alkylation of sulfhydryl groups as well as the native form of the molecule, ECP, EPO by itself, as well as EPO + H2O2 + halide, but not EDN, cause dose-related damage to the tracheal epithelium. The lowest concentrations of MBP and ECP causing damage were 10 and 100 micrograms/ml, respectively. In contrast, EDN, although biochemically similar to ECP, did not damage the tracheal epithelium in concentrations of up to 200 micrograms/ml. MBP caused exfoliation, as well as bleb formation and ciliostasis. EPO in the presence of the H2O2-producing enzyme glucose oxidase (GO), Cl-, 0.11 M, and iodide caused ciliostasis, bleb formation, and exfoliation of epithelial cells at concentrations as low as 1 U/ml (3.9 micrograms/ml). EPO + GO in the presence of Cl-, 0.11 M, alone or with Cl- and l-, 10(-4) M, or Cl- and Br-, 5 x 10(-5) M, were all toxic to epithelium. Surprisingly, EPO by itself caused partial ciliostasis, bleb formation, and exfoliation of epithelial cells in a dose-related manner at concentrations as low as 10 to 30 U/ml (39 to 121 micrograms/ml). These results confirm prior observations showing the toxicity of MBP to tracheal epithelium and indicate that ECP and EPO alone, as well as EPO + GO + halide, cause damage. Thus, several eosinophil granule proteins are able to damage respiratory epithelium.
...
PMID:Toxicity of eosinophil cationic proteins for guinea pig tracheal epithelium in vitro. 292 79

A protein (eosinophil-activating factor, EAF), which enhances the capacity of human peripheral blood eosinophils to kill antibody-coated schistosomula of Schistosoma mansoni, has been partially purified from supernatants of cultured peripheral blood mononuclear cells by sequential chromatography on Sephacryl S200 and DEAE-cellulose. This protein is acidic with a molecular mass on gel filtration of 40 +/- 7 kDa. It not only enhances the activity of eosinophils against schistosomula but also increases their ability to lyse antibody-coated, herpes simplex virus-infected Chang liver cells. It enhances the production of superoxide and hydrogen peroxide by eosinophils that occurs both spontaneously and in response to opsonized zymosan. However, increased respiratory burst activity does not appear to be responsible for the enhancement of eosinophil-mediated killing of schistosomula, since a comparable or greater increase in hydrogen peroxide production is induced by column fractions that have little or no effect on schistosomulum killing. EAF enhances eosinophil degranulation, both spontaneously and after incubation with opsonized zymosan. Enhanced degranulation is associated with release of eosinophil peroxidase and eosinophil cationic protein. These findings suggest that EAF enhances the capacity of eosinophils to kill parasites by increasing the extent of eosinophil degranulation and the amount of toxic granule proteins that are secreted.
...
PMID:Partial purification and biological properties of an eosinophil-activating factor. 299 4

Composition of azurophil and specific granules from human polymorphonuclear neutrophils and granules from eosinophils is presented. Biosynthesis of the granule proteins is discussed in detail with particular emphasis on neutrophil myeloperoxidase (MPO) and eosinophil cationic protein (ECP).
...
PMID:The biosynthesis of neutrophil and eosinophil granule proteins. 302 43

The concentrations of eosinophil cationic protein (ECP), a specific granule constituent of eosinophil granulocytes, were measured in bronchoalveolar lavage (BAL) fluid from patients with adult respiratory distress syndrome (ARDS). The mean level was 163 +/- 85 (SD) micrograms/L and significantly increased (p less than 0.001) compared with the levels in control subjects (19 +/- 18 micrograms/L). The BAL fluid concentrations of myeloperoxidase (MPO) were also significantly increased in ARDS, indicating a local neutrophil activation. A significant correlation was found between BAL fluid ECP and MPO, suggesting a common activator of eosinophils and neutrophils. No relation was seen between BAL fluid ECP or MPO and degree of complement consumption, suggesting that other mechanisms besides complement activation may underlie granulocyte activation in ARDS. Lavage ECP levels correlated strongly with the severity of lung damage defined by pulmonary oxygenation index (PaO2/inspired fraction of O2). Activation of eosinophils, neutrophils, and the complement system is not specific for ARDS but was also observed in patients after major surgery, but at a significantly lower level (p less than 0.001). It is concluded that eosinophil activation is part of the inflammatory process in the lung in ARDS. The association observed between elevated lavage fluid levels of ECP and reduced pulmonary function in ARDS might reflect a pathophysiologic role for ECP and other cytotoxic eosinophil products in this syndrome and should be evaluated.
...
PMID:Eosinophil activation in the lung is related to lung damage in adult respiratory distress syndrome. 303 Jan 69

Ultrastructural study of mucosal eosinophils in a case of eosinophilic gastroenteritis involving stomach, duodenum and ileum showed an altered structure in ulcerated duodenal areas. The electron core density of eosinophil granules was inverted or disappeared and tubulovesicular structures occurred. Using immunogold staining with specific antibodies, major basic protein was detected diffusely in the matrix of eosinophil granules and out of the granules in tight association with extragranular membrane formations. In contrast, eosinophil cationic protein and eosinophil peroxidase were normally distributed in the granule matrix. When compared with the eosinophils in macroscopically normal duodenal mucosa in the same patient, these changes support a role for major basic protein in tissue damage in eosinophilic gastroenteritis. The diffusion of one granule protein from the granules to the exterior of the cells favours the view of a selective release of eosinophil mediators.
...
PMID:Eosinophilic gastroenteritis: ultrastructural evidence for a selective release of eosinophil major basic protein. 323 90


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>