Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.37 (neutrophil elastase)
 4,078 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Few systematic studies have been made of amounts or of the composition of gingival crevicular fluid (GCF) from different sites or of the stability of GCF parameters over time. These data are needed to better understand the relation of GCF composition to periodontal health status. This report gives the volume and the amounts of lactate dehydrogenase (LDH), aryl sulfatase (AS) and neutrophil elastase (NE) for GCF collected from 6 samplings of 6 standard gingival sites in 11 young adult subjects over a 6-week period. Attachment loss (3 mm) was noted at only 1 of the 66 sites. The mean gingival index of the 11 subjects ranged from 0.33 to 1.67. The GCF volume and activity/sample of LDH and AS but not NE differed among subjects. However, differences among subjects were not found when the GCF enzyme activities were expressed as activity/microliter GCF. GCF volume and LDH, AS and NE activity all differed among the 6 sites when the activities were expressed as either quantity/sample or microliter GCF. These data show that differences among sites must be carefully considered in evaluation of GCF data. Fluid volume and LDH, AS and NE activity all varied from sampling to sampling. However, differences among sites were retained throughout the experimental period.
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PMID:Repeated measurement of crevicular fluid parameters at different sites. 206 16

Neutrophils play a role in the development of pulmonary edema in many models of the adult respiratory distress syndrome, but the mechanism of their action is not completely understood. We asked whether two neutrophil secretory products, human neutrophil cationic protein (NCP) and human neutrophil elastase (HNE), would nonenzymatically alter the movement of albumin across a cultured endothelial monolayer. Both enzymes were inactivated by heating before use. HNE was additionally enzymatically inactivated with a chloromethylketone oligopeptide (CMK) inhibitor and with alpha 1-proteinase inhibitor (alpha 1-PI). Heated NCP, heated HNE, and CMK-complexed HNE all increased transendothelial albumin transfer. The cation protamine also increased albumin transfer across the endothelium and this increase was blocked by heparin. Alpha 1-PI and fetal bovine serum also prevented the cationic proteins from increasing albumin transfer. Using the release of lactate dehydrogenase as a marker of cytotoxicity, heated HNE was toxic to endothelial cells, heated NCP had only minimal toxicity, and protamine had no toxicity. Changes in endothelial cell shape with gap formation was seen after exposure to both heated HNE and heated NCP. Both the cytotoxicity associated with heated HNE and the cell shape changes associated with heated NCP and heated HNE could be blocked by heparin. These results suggest that in addition to neutrophil proteases and reactive O2 molecules, neutrophil-derived cationic proteins can directly and nonenzymatically contribute to edema formation during acute inflammation.
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PMID:Cationic neutrophil proteins increase transendothelial albumin movement. 364 23

A neonatal rat aorta smooth muscle cell culture system with a unique elastin-rich extracellular matrix was used as a model substrate for elastases. To study the susceptibility to solubilization of insoluble elastin, cultures were incubated in the presence of human neutrophil elastase (HNE) or porcine pancreatic elastase (PPE) and in the absence of serum for periods up to 45 min. Both the incubation media and cell layers were then assessed for elastin and collagen markers, total protein, and lactate dehydrogenase (LDH). Although HNE and PPE exhibited comparable activity against elastin purified from the cell layer, HNE exhibited a 6.7- to 25-fold reduction in its elastin solubilizing activity using intact cell layers as compared with the purified elastin, whereas PPE exhibited only a 1.5- to 2.5-fold reduction. This effect could not satisfactorily be explained as preferential inhibition of HNE activity in the culture system, because the amount of protein solubilized by HNE was 59% that of PPE. The mean elastin content of PPE-solubilized protein was 110% that of the elastin content of the corresponding cell layer; the value for HNE-solubilized protein was only 16%. Thus, the amount of elastin per microgram of solubilized protein for HNE was 15% that for PPE. Possible explanations for the greatly diminished elastolytic activity of HNE in the culture system include the preference of HNE for other substrates in the cell layer, the inability of HNE to penetrate sufficiently into the cell layer, and the presence of sulfated glycosaminoglycans in the vicinity of the elastin that act in an inhibitory fashion. Although there was extensive proteolytic damage to the extracellular matrix, LDH and DNA measurements indicated that little loss of cells or cell viability occurred. The observed differences in elastolytic activity of HNE and PPE in the culture system parallel the relative emphysema-inducing potency of the elastases in the hamster model of elastase-induced emphysema.
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PMID:Elastin in a neonatal rat smooth muscle cell culture has greatly decreased susceptibility to proteolysis by human neutrophil elastase. An in vitro model of elastolytic injury. 366 86

The effects of neutrophil elastase on endothelial prostacyclin (PGI2) production, nucleotide release, and responsiveness to vasoactive agents were compared with the effects of cathepsin G (the other major neutral protease of neutrophils), pancreatic elastase, trypsin, chymotrypsin, and thrombin. PGI2 production by pig aortic endothelial cells cultured on microcarrier beads and perfused in columns was stimulated in a dose-dependent manner by trypsin, chymotrypsin, and cathepsin G (1-100 micrograms/ml for 3 min). Thrombin, while active at low concentrations (0.1-10 National Institutes of Health U/ml), induced smaller responses. Neutrophil and pancreatic elastase had little or no effect on PGI2 production. Dose-dependent, selective release of adenine nucleotides was induced by neutrophil elastase (3-30 micrograms/ml). The other proteases were much less active; for example, trypsin (100 micrograms/ml) induced a response only approximately 5% as great as did 30 micrograms/ml neutrophil elastase. After exposure to 30 micrograms/ml neutrophil elastase, cells did not exhibit the characteristic burst of PGI2 production in response to extracellular ATP; responsiveness gradually returned after 40-120 min. This effect was not seen with the other proteases. Elastase partly inhibited responses to bradykinin and had no effect on PGI2 production that was stimulated by ionophore A23187. There was no evidence of cytotoxicity, as measured by release of lactate dehydrogenase. Neutrophil degranulation can generate concentrations of elastase and cathepsin G comparable with those tested in the present study, and the effects of these enzymes on endothelial function lead us to suggest that they may play a role in vasoregulation and vascular pathology.
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PMID:Effects of neutrophil elastase and other proteases on porcine aortic endothelial prostaglandin I2 production, adenine nucleotide release, and responses to vasoactive agents. 643 44

We compared the elastase and lysozyme activities of cells obtained by bronchoalveolar lavage from normal smokers and nonsmokers. After total and differential cell counts were obtained for the initial lavage cell population, we determined the enzyme activities of the total lavage cell population, the culture vessel's adherent alveolar macrophage cell fraction, and the cell culture supernatant medium. Our data indicated that macrophages, particularly from smokers, synthesized a calcium-dependent activity against a synthetic elastase substrate, succinyl-trialanine-p-nitroanilide. This activity was enhanced in smokers and was distinct from the polymorphonuclear leukocyte elastase as measured with this synthetic substrate. Measurements using insoluble elastin labeled with 3H demonstrated that smokers' macrophages also contained a serine-proteinase activity whose inhibitor profile resembled that of polymorphonuclear leukocyte elastase. Finally, macrophages from smokers secreted 5 times more lysozyme and contained more lactate dehydrogenase activity than did nonsmokers' macrophages. We suggest that pulmonary macrophages take up the polymorphonuclear leukocyte elastase and contain a synthetic substrate, "elastase". The biologic significance of this elastase activity is unclear. The enhanced lysozyme secretion by smokers' alveolar macrophages indicated increased biosynthetic activity by these cells.
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PMID:Elastase and lysozyme activities in human alveolar macrophages. Effects of cigarette smoking. 689 36

Neutrophil-mediated injury to hepatocytes was evaluated in vitro. A new in vitro coculture system of neutrophils and a human hepatoblastoma cell line (HuH-6), instead of normal hepatocytes, was established. Recombinant human tumor necrosis factor (TNF) activated neutrophils to release neutrophil elastase and showed the significant cytotoxicity for HuH-6 cells, which was determined by measuring the release of the cytoplasmic enzyme, lactate dehydrogenase (LDH), from HuH-6 cells. The concentration of neutrophil elastase from zymosan-primed/TNF (1.0 ng/ml)-stimulated neutrophils cocultured with HuH-6 cells reached to the level of 1.59 +/- 0.18 micrograms/10(6) cells in 24 hr. The release of LDH from HuH-6 cells in this coculture system was 84.8 +/- 17.8 units/liter after 24 hr incubation. Purified human neutrophil elastase also increased LDH release from HuH-6 cells. When HuH-6 cells were cocultured with zymosan-primed/TNF (1.0 ng/ml)-stimulated neutrophils, the secretion of the negative acute phase reactant (APR), alpha-fetoprotein, from HuH-6 cells was significantly decreased, and the production of the positive APR, pancreatic secretory trypsin inhibitor, was decreased in response to the stimulation of interleukin 6. Urinary trypsin inhibitor, the inhibitor of neutrophil elastase, decreased the release of LDH from HuH-6 cells cocultured with stimulated neutrophils, while superoxide scavenger did not. These results show that human neutrophils activated by TNF injure hepatocytes, thus causing hepatic dysfunction, through the release of neutrophil elastase.
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PMID:The mechanism of hepatic cellular injury in sepsis: an in vitro study of the implications of cytokines and neutrophils in its pathogenesis. 769 33

Escherichia coli endotoxin (0.1 to 1000 micrograms/ml) stimulated the release of neutrophil chemotactic activity (P < 0.001) and induced bronchial epithelial cell (BEC) cytotoxicity assessed by lactate dehydrogenase release (P < 0.001). Endotoxin (100 micrograms/ml) inhibited BEC accumulation (P < 0.001). In the present study, we investigated the role of proteolytic activity of BECs per se in response to endotoxin. Several structurally and functionally different antiproteases, alpha 1 protease inhibitor, soybean trypsin inhibitor, two chloromethyl ketone derivatives (N-tosyl-L-lysine chloromethyl ketone and methoxysuccinyl-Ala-Ala-Pro-Val chloromethyl ketone), and L-658,758, a neutrophil elastase inhibitor, attenuated the release of neutrophil chemotactic activity and lactate dehydrogenase (P < 0.01). alpha 1-Protease inhibitor and N-tosyl-L-lysine chloromethyl ketone attenuated the inhibition of BEC accumulation by endotoxin (P < 0.001). The proteolytic enzyme activity measured by synthetic substrates revealed that endotoxin significantly augmented the serine proteolytic activity in the cell layers. Culture supernatant fluids and cell lysates of BECs in the presence of endotoxin solubilized 14C-labeled casein. These data suggest that responses of BECs to endotoxin may involve activation of cellular proteolytic activity.
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PMID:Antiproteases modulate bronchial epithelial cell responses to endotoxin. 774 15

Neutrophils are thought to play a key role in tissue injury. We investigated the role of human neutrophil-derived elastase in the induction of injury to human pulmonary artery endothelial cells. Incubation of endothelial cells with neutrophils increased the release of lactate dehydrogenase activity, thrombomodulin, and preloaded fura-2 from endothelial cells, indicating that neutrophils induce endothelial cell injury. Attachment alone of neutrophils to endothelial cells appeared to induce activation because elastase release and N-formyl-mentionyl-leucyl-phenylalanine (fMLP)-induced superoxide (O2) production from neutrophils incubated with endothelial cells were greater than from neutrophils only. When endothelial cell were incubated with neutrophils stimulated by fMLP or phorbol myristate acetate, the amount of elastase in the medium and endothelial cell damage was further enhanced. However, when neutrophils were blocked from direct attachment to endothelial cells using a membrane filter, endothelial cell damage was ameliorated, while exogenous neutrophil elastase and medium containing neutrophil-released elastase did not induce endothelial cell injury. An inhibitor of neutrophil elastase, ONO-5046 Na, as well as erythromycin, which reduces neutrophil-derived elastase, dramatically inhibited neutrophil-induced endothelial cell injury. Superoxide dismutase (SOD) partially inhibited injury. Injury was completely inhibited by treatment with a combination of ONO-5046 Na and SOD. These results suggest that attachment of neutrophils to endothelial cells is important for endothelial cell damage and that neutrophil-derived elastase plays an important role in endothelial cell injury in combination with O2. In addition, ONO-5046 Na and erythromycin may be useful in treating diseases worsened by excessive neutrophil activity.
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PMID:The role of neutrophil elastase in human pulmonary artery endothelial cell injury. 906 13

It was hypothesized that neutrophil elastase released from activated neutrophils may play an important role in the pathogenesis of pulmonary fibrosis. In the present study, we measured the neutrophil elastase:alpha-1-proteinase inhibitor complex (E-PI) in serum and bronchoalveolar lavage fluid (BALF) in 26 patients with pulmonary fibrosis and evaluated the correlation between E-PI levels and several parameters. E-PI levels in serum of patients with pulmonary fibrosis (635.8+/-112.0 ng.mL(-1)) were significantly elevated compared to normal nonsmokers (122.0+/-4.0 ng.mL(-1)) as well as normal smokers (132.8+/-8.4 ng.mL(-1)) (p<0.01). E-PI levels in serum significantly correlated with hepatocyte growth factor (HGF) levels in serum, C-reactive protein (CRP), and negatively correlated with arterial oxygen tension (Pa,O2), and arterial carbon dioxide tension (Pa,CO2). E-PI/albumin levels in BALF significantly correlated with HGF/albumin levels in BALF, lactate dehydrogenase (LDH)/albumin in BALF, total number of inflammatory cells (alveolar macrophages and neutrophils) in BALF, and several markers derived from epithelial cells in BALF. Our data demonstrated: 1) neutrophil elastase:alpha-1-proteinase inhibitor complex in serum increased in patients with pulmonary fibrosis; and 2) neutrophil elastase:alpha-1-proteinase inhibitor complex in serum and bronchoalveolar lavage fluid correlated with clinical parameters in pulmonary fibrosis. These results suggest that neutrophil elastase may play a significant role in the process of lung injury in pulmonary fibrosis.
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PMID:Neutrophil elastase: alpha-1-proteinase inhibitor complex in serum and bronchoalveolar lavage fluid in patients with pulmonary fibrosis. 954 80

The levels of marker enzymes for liver function, namely transaminases (SGPT, SGOT), creatine phosphokinase (CPK), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) were estimated in the sera of burn patients by administering trypsin: chymotrypsin preparation and comparing with an untreated group. Neutrophil proteolytic activity was also measured by assaying the lysosomal enzymes, namely neutrophil elastase and cathepsin D. Our earlier studies have already proved the efficacy of the above enzyme preparation to burn patients on the enhancement of vascular responses during the acute phase of the burn injury. These beneficial responses were brought about by the modulation of acute phase proteins expressed in the liver. Hence, it is of interest to study the changes in the above mentioned liver enzymes and certain lysosomal enzymes in the serum during the first 10 days of burn injury. The levels of liver and lysosomal enzymes markedly decreased in the treated group when compared with the untreated group. The enzyme studies clearly indicated that the initial rise in the liver enzymes was minimized in the treated group when compared with the untreated group and this helped in reducing the stress to the liver in the treated cases. The increase in the activity of alpha 1-antitrypsin and alpha 2-macroglobulin and decreased levels of C-reactive protein are attributed to the reduction of proteolytic enzyme levels in the treated group and minimizing the degradative changes during wound repair.
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PMID:Serum enzymatic changes modulated using trypsin: chymotrypsin preparation during burn wounds in humans. 956 24


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