Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0034067 (emphysema)
 11,506 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Secretory leukocyte inhibitor (SLPI) is a potent inhibitor of serine proteinases, but sensitive to oxidative inactivation due to a methionine residue in the active centre of the inhibitor. We compared the potency of an oxidation-resistant mutant of recombinant SLPI with native recombinant SLPI in lipopolysaccharide (LPS)-induced emphysema in the hamster. Application of this oxidation-resistant mutant reduced the induced emphysema by 70 and 85% in two separate series of experiments. In contrast, an equal amount of native rSLPI resulted in significantly lower inhibition, 30 and 23%, respectively (P = 0.002). To demonstrate the effect of oxygen radicals upon a single LPS instillation in the lungs, we measured anti-neutrophil elastase activity in lung lavage fluid at 10 and 24 h after the instillation of a mixture of LPS and native rSLPI. We found that residual native rSLPI was only 70 and 55% active, respectively. The rSLPI-mutant remained 93% active in a similar experiment. The native and mutant inhibitor showed equal potency against proteinases in a granule extract of hamster neutrophils. We conclude that the replacement of methionine by leucine in the inhibitory centre of rSLPI results in a decreased sensitivity to oxidative inactivation and that this alone is sufficient to explain the greater efficiency of the rSLPI-mutant in reducing the extent of LPS-induced emphysema.
 ...
PMID:Potency of an oxidation-resistant mutant of secretory leukocyte proteinase inhibitor in lipopolysaccharide-induced emphysema in hamsters. 809 18

Secretory leukocyte protease inhibitor (SLPI) is a 12 kD nonglycosylated serine antiproteinase secreted by cells of mucosal surfaces. In human lung, SLPI is present in the respiratory epithelium. It is the major barrier to tissue destruction mediated by the polymorphonuclear leukocyte (PMN) serine proteinases, elastase and cathepsin G, within the upper respiratory tract. We have recently described a third PMN serine proteinase, proteinase-3, that like elastase causes lung matrix destruction and experimental emphysema. The current studies examine interactions between SLPI and proteinase-3. The results show that: (1) SLPI and its reactive-site variants have no or minimal inhibitory activity against proteinase-3; (2) native SLPI does not complex with proteinase-3; (3) proteinase-3 selectively degrades both native and oxidized SLPI; (4) the cleavage of SLPI by proteinase-3 occurs at the peptide bond COOH-terminal to Ala-16 in the NH2-terminal domain of SLPI.
 ...
PMID:Interaction of secretory leukocyte protease inhibitor with proteinase-3. 810 Jul 9

1. alpha 1-antitrypsin is an antiprotease that inhibits the neutrophil elastase enzyme, and belongs to a family of structurally related serine proteinase inhibitors (serpins). Its methionine358 residue determines the specificity for elastase. 2. The normal M-type alpha 1-antitrypsin is mainly synthesized in the liver parenchymal cells and transported to the plasma. Abnormal Z-mutant alpha 1-antitrypsin is retained in the endoplasmic reticulum, which leads to its intracellular accumulation and to markedly decreased plasma levels. 3. In normal conditions, alpha 1-antitrypsin protects the lungs from destruction by the proteolytic neutrophil elastase. A protease/antiprotease imbalance in the lung is responsible for the development of emphysema in severe alpha 1-antitrypsin deficiency and in cigarette smokers, and accounts for the marked acceleration of the lung disease in smoking alpha 1-antitrypsin deficient patients. Smoking has to be avoided in alpha 1-antitrypsin deficient patients. Replacement therapy with plasma-derived alpha 1-antitrypsin seems indicated in alpha 1-antitrypsin deficient patients with emphysema. 4. Intracellular accumulation of abnormal Z-alpha 1-antitrypsin molecules in liver parenchymal cells may lead to liver disease, ranging from neonatal cholestasis to adulthood cirrhosis and hepatocellular carcinoma. End-stage liver disease can be treated by liver transplantation, which is followed by a phenotypic conversion. 5. Diagnosis of alpha 1-antitrypsin deficiency related disease relies on the presence of a low serum concentration of alpha 1-antitrypsin, and of periodic-acid Schiff positive globules in the liver parenchymal cells. Isoelectric focusing of the serum identifies the protease inhibitor phenotype. The protease inhibitor phenotype is determined by the independent expression of the two parental alpha 1-antitrypsin alleles. It is determinant of the serum level and of the risk for development of lung or liver disease.
 ...
PMID:Alpha 1-antitrypsin deficiency: an overview. 839 99

Proteinase-3 (PR3) is a polymorphonuclear leukocyte serine proteinase that is a potent inducer of emphysema in experimental models. PR3 is also the target antigen associated with Wegener's granulomatosis. By analysis of a panel of somatic cell hybrids, the gene encoding PR3 was localized previously to chromosome 19; we have used fluorescence in situ hybridization to sublocalize this gene to 19p13.3.
 ...
PMID:Localization of the gene encoding proteinase-3 (the Wegener's granulomatosis autoantigen) to human chromosome band 19p13.3. 850 76

Thirty years ago the concept of the elastase:antielastase hypothesis was introduced. Neutrophil elastase:A1PI balance was found to be critical, predisposing patients deficient in A1PI to panacinar emphysema; however, the causative elastases in common cigarette-induced pulmonary emphysema are unclear. Several members of the serine, cysteine, and metalloproteinase families have been identified in inflammatory and resident lung cells. We propose to use gene-targeted mice, deficient in individual elastases to determine the relative contribution of candidate elastases to cigarette-smoking-related emphysema. This does not guarantee that humans will respond to cigarette smoke with the same array of elastases as mice. However, these studies may guide labor intensive therapeutic trials with specific proteinase inhibitors and ultimately lead to rational therapy.
 ...
PMID:The pathogenesis of emphysema: the elastase:antielastase hypothesis 30 years later. 860 21

Proteinase 3 is a human polymorphonuclear leukocyte serine proteinase that degrades elastin in vitro and causes emphysema when administered by intratracheal insufflation into hamsters. Proteinase 3, stored in the azurophilic granules, is expressed in progenitor cells of myeloid origin. In the present study, the biosynthesis, processing, and intracellular transport of the enzyme was investigated in the human myelomonocytic cell line U937. Proteinase 3 is initially identified as a 35-kDa precursor and converted into the 29-kDa mature form within 3 h. By using a combination of techniques including amino-terminal sequencing, we identified the 35-kDa form as a zymogen containing an activation dipeptide but lacking the amino-terminal 25 residues, presumably the result of cleavage by a signal peptidase. Tunicamycin treatment and alkalinization of acidic cell compartments with NH4Cl did not prevent the processing of the proteinase 3 zymogen into the mature form, suggesting that the enzyme is targeted to the cytoplasmic granules by a mechanism other than the mannose 6-phosphate receptor. Brefeldin A inhibited the zymogen processing, suggesting that the dipeptide cleavage occurred in a post-Golgi organelle. The enzyme responsible for the removal of the dipeptide is a cysteine proteinase since E-64d, a class-specific inhibitor, prevented processing. However, treatment of cells with a dipeptidyl peptidase I inhibitor, Gly-Phe-diazomethyl ketone and with the lysosomotropic agents, NH4Cl and chloroquine, did not prevent dipeptide cleavage, indicating that the processing enzyme for proteinase 3 is not dipeptidyl peptidase I. In contrast, Gly-Phe-diazomethyl ketone inhibited cleavage of the dipeptide from cathepsin G. This indicates that processing of proteinase 3 is distinct from that of cathepsin G. Proteinase 3 is also processed at the COOH-terminal extension. Cleavage takes place next to Arg-222, suggesting that a trypsin-like proteinase is involved in the COOH-terminal processing.
 ...
PMID:Biosynthesis and processing of proteinase 3 in U937 cells. Processing pathways are distinct from those of cathepsin G. 862 89

The serpin superfamily of serine proteinase inhibitors contains many members but the best-characterized is the plasma protein alpha 1-antitrypsin. its genetic deficiency is associated, in the homozygote, with hepatic damage that may progress to cirrhosis and hepatocellular carcinoma. Low levels of circulating alpha 1-antitrypsin fail to protect the lungs against proteolytic attack and predispose the homozygote to early onset pan-lobular emphysema, bronchiectasis and asthma. The major cause of alpha 1-antitrypsin deficiency, the Z mutation (Glu342Lys), results in the accumulation of protein in the endoplasmic reticulum of the liver. Using a structural approach, we have shown that the hepatic inclusions result from a protein-protein interaction between the reactive centre loop of one molecule and the beta-pleated sheet of a second. This loop-sheet polymerization is now also recognized to be the basis of deficiencies associated with mutations of C1-inhibitor, antithrombin and alpha 1-antichymotrypsin. Our recent solution of a crystal structure of a thermostable mutant of alpha 1-antitrypsin shows the detailed interactions that result in loop-sheet linkage and helps to explain the mechanism of action of this family of proteinase inhibitors.
 ...
PMID:New insights into the structural basis of alpha 1-antitrypsin deficiency. 897 59

FK706, sodium 2-[4-[[(S)-1-[[(S)-2-[[(RS)-3, 3, 3-trifluoro-1-isopropyl-2-oxopropyl]aminocarbonyl]pyrrolidin -1-yl]carbonyl]-2-methylpropyl] aminocarbonyl] benzoylamino] acetate, C26H32F3N4NaO7, is a synthetic water-soluble inhibitor of human neutrophil elastase. This compound demonstrated a competitive and slow-binding inhibition of human neutrophil elastase with a Ki of 4.2 nM. In studies using synthetic substrates, FK706 inhibited human neutrophil elastase activity and porcine pancreatic elastase activity with respective IC50 values of 83 and 100 nM. FK706, however, inhibited more weakly, (IC50 values > 340 microM) other serine proteinases such as human pancreatic alpha-chymotrypsin, human pancreatic trypsin and human leukocyte cathepsin G. FK706 also effectively inhibited the hydrolysis of bovine neck ligament elastin (2 mg/ml final concentration) by human neutrophil elastase (4 microg/ml final concentration) with an IC50 value of 230 nM. FK706 protected animals against human neutrophil elastase (50 microg/animal)-induced lung hemorrhage with ED50 values of 2.4 microg/animal by intratracheal administration and 36.5 mg/kg by intravenous administration, respectively. Subcutaneous administration of FK706 significantly suppressed human neutrophil elastase (20 microg/paw)-induced paw edema in mice in a dose-dependent manner (47% inhibition at a dose of 100 mg/kg). These results suggest that FK706 would be a useful tool for investigating the role of human neutrophil elastase in inflammatory disorders associated with an excess of elastase, such as pulmonary emphysema, adult respiratory distress syndrome, septic shock, cystic fibrosis, chronic bronchitis and rheumatoid arthritis.
 ...
PMID:Biochemical and pharmacological characterization of FK706, a novel elastase inhibitor. 938 82

Proteinase-3 (PR-3) and neutrophil elastase (NE) are polymorphonuclear leukocyte serine proteinases that degrade extracellular matrix proteins including elastin and appear to be involved in the pathogenesis of several diseases characterized by tissue destruction most notably emphysema and Wegener's granulomatosis. In this report we characterize and compare the mouse PR-3 and NE genes and establish by FISH analysis a common location on mouse chromosome 10C2. Each gene consists of five exons and four introns conserving the typical granule-associated serine proteinase gene structure. The mouse PR-3 gene (Prtn3) is approximately 3.7 kb and is within 2.2 kb of the smaller (1.7 kb) NE gene (Ela2). The larger size of Prtn3 is accounted for by differences in intron sizes. A comparison between the mouse and human PR-3 cDNA reveals 73% homology, however, this drops to 60% when the amino acid sequences are compared. Homology between the mouse and human NE cDNA is 77% for both the cDNA and amino acid sequences. The catalytic triad and its placement are conserved among the four genes. The proximal promoter of mouse Prtn3 contains a TATA box, c-myb and an ets transcriptional site. As these are functional elements in the mouse Ela2 promoter they may also be important in the expression of Prtn3.
 ...
PMID:Characterization and localization of the genes for mouse proteinase-3 (Prtn3) and neutrophil elastase (Ela2). 992 46

Pulmonary emphysema refers to a lung disorder characterized by a diffuse destruction of the alveolar walls resulting in enlargement of the distal airspaces. The disease is usually a chronic, progressive, and disabling disorder. The concept of proteinase/antiproteinase imbalance evolved from the identification of patients with alpha 1-antytripsin deficiency, and from the development of experimental emphysematous lesions using different enzymes. For a long time, this concept was seen as an elastase/antielastase imbalance, with the consequent degradation of elastin. Recent evidence, however, suggests that an intricate process of pulmonary remodeling occurs during the development of emphysema, where a complex network of serine proteases and metalloproteinases capable of degrading different extracellular matrix molecules, primarily, but not exclusively fibrillar collagens and elastin, are implicated in the pathogenesis of this disease.
 ...
PMID:Proteinase-antiproteinase imbalance in the pathogenesis of emphysema: the role of metalloproteinases in lung damage. 998 67


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