Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.4.21.7 (plasmin)
9,023 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A library of compounds were prepared by reacting 2-(bromomethyl)-1, 2-benzisothiazol-3(2H)-one 1,1-dioxide (5) with commercially available carboxylic acids in the presence of potassium carbonate or a tertiary amine base. From this library, (1,1-dioxido-3-oxo-1, 2-benzisothiazol-2(3H)-yl)methyl N-[(phenylmethoxy)carbonyl]-beta-alanate (7b) emerged as a potent inhibitor of human mast cell tryptase (IC50 = 0.85 microM). Extension of the side chain of 7b by two carbons gave (1, 1-dioxido-3-oxo-1,2-benzisothiazol-2(3H)-yl)methyl 5-[[(phenylmethoxy)carbonyl]amino]pentanoate (7d) which was an 8-fold more potent inhibitor (IC50 = 0.1 microM). Further modification of this series produced benzoic acid derivative (1, 1-dioxido-3-oxo-1,2-benzisothiazol-2(3H)-yl)methyl 4-[[(phenylmethoxy)carbonyl]amino]benzoate (7n) which is the most potent inhibitor identified in this series (IC50 = 0.064 microM). These compounds exhibit time-dependent inhibition consistent with mechanism-based inhibition. For 7b, the initial enzyme velocity is not a saturable function of the inhibitor concentration and the initial Ki could not be determined (Ki > 10 microM). The steady-state rate constant, Ki, was determined to be 396 nM. On the other hand, compounds 7d and 7n are time-dependent inhibitors with a saturable initial complex. From these studies, an initial rate constant, Ki, for 7d and 7n was found to be 345 and 465 nM, respectively. The steady-state inhibition constants, Ki, for 7d and 7n were calculated to be 60 and 52 nM, respectively. Compound 7n is a 13-fold more potent inhibitor than 7b, and these kinetic studies indicate that the increase in inhibitory activity is due to an increase in initial affinity toward the enzyme and not an increase in chemical reactivity. These inhibitors generally show high selectivity for tryptase, being 40-fold weaker inhibitors of elastase, being 100-fold weaker against trypsin, and showing no inhibition against thrombin. These compounds are not inhibitors of thrombin, plasmin t-PA, urokinase, and factor Xa (IC50 > 33 microM). In the delayed-type hypersensitivity (DTH) mouse model, a model of skin inflammation, a 5% solution of 7d reduced edema by 69% compared to control animals.
...
PMID:1,2-Benzisothiazol-3-one 1,1-dioxide inhibitors of human mast cell tryptase. 982 54

Myeloperoxidase (MPO) is an important component of the neutrophil response to microbial infection. In this paper we report an additional activity of MPO, the potent and selective inhibition of human mast cell tryptase. MPO inhibits human mast cell tryptase in a time-dependent manner with an IC50 of 16 nM at 1 h. In contrast, MPO does not inhibit trypsin, thrombin, plasmin, factor Xa, elastase, or cathepsin G. It is the native protein conformation of MPO and not its enzyme activity that is responsible for tryptase inhibition. Heparin, at high concentrations, can prevent the inhibition of tryptase by MPO. We have shown by size-exclusion chromatography that MPO promotes the dissociation of active tryptase tetramer to inactive monomer. These data suggest that MPO inhibits tryptase by interfering with the heparin stabilization of tryptase tetramer. We have previously shown that lactoferrin (another neutrophil-associated protein) also inhibits tryptase activity by a similar mechanism. The finding that MPO is a potent inhibitor of tryptase lends further support to the hypothesis that neutrophil proteins, such as MPO and lactoferrin, may play a regulatory role as endogenous suppressers of tryptase enzyme activity.
...
PMID:Neutrophil myeloperoxidase is a potent and selective inhibitor of mast cell tryptase. 1033 72

A markedly elevated serum level of mast cell tryptase (77.6 microg/L; 95th percentile in normals 13.5 microg/L) was detected in a patient treated for 5 years with wasp venom immunotherapy because of severe anaphylaxis following a wasp sting. Retrospective analysis of stored serum samples taken during the course of immunotherapy revealed that the tryptase level had been elevated for at least 3 years. Despite several dermatological examinations, skin changes of mastocytosis had been missed. Re-examination of the patient revealed sparse macules on the thorax and thighs; Darier's sign was negative. Histologically, mast cell accumulation in these lesions was demonstrable. No signs of systemic mastocytosis were detected. The most appropriate diagnosis was telangiectasia macularis eruptiva perstans. Even in patients with highly elevated tryptase levels, mastocytosis may go undiagnosed. As mastocytosis predisposes to severe anaphylaxis, the condition should be looked for in patients with such reactions by clinical examination and measurement of serum tryptase levels.
...
PMID:Mastocytosis associated with severe wasp sting anaphylaxis detected by elevated serum mast cell tryptase levels. 1060 62

Evidence is accumulating indicating that trypsin stimulates divergent cellular reactions through the proteinase-activated receptor, in addition to its role as the digestive enzyme. In this report, we introduce (2R,4R)- 4-phenyl-1-[N(alpha)-(7-methoxy-2-naphthalenesulfonyl)-l-arginyl]- 2-p iperidinecarboxylic acid as a potent and selective trypsin inhibitor. The agent inhibited trypsin competitively with the K(i) value of 0. 1 micrometer. It inhibited thrombin weakly (K(i) = 2 micrometer) and did not inhibit plasmin, plasma kallikrein, urokinase, and mast cell tryptase (K(i) values for these enzymes are >60 micrometer). Comparative studies with several established proteinase inhibitors revealed that the compound was the first small molecular weight trypsin inhibitor without tryptase inhibitory activity. A docking study has provided a plausible explanation for the molecular mechanism of the selective inhibition showing that the agent fits into the active site of trypsin without any severe collision but that it comes into clash at the 4-phenyl group of piperidine ring against the "60-insertion loop" of thrombin and at the 7-methoxy-2-naphthalenesulfonyl group against Gln(98) of tryptase.
...
PMID:Selective inhibition of trypsin by (2R,4R)-4-phenyl-1-[Nalpha-(7- methoxy-2-naphthalenesulfonyl)-L-arginyl]-2-piperidinecarboxylic acid. 1074 93

In this study the routine use of different parameters for evaluation of the overall therapeutic outcome in atopic dermatitis was investigated. The disease activity of 117 randomly selected hospitalized patients suffering from atopic dermatitis was routinely assessed using the Severity Scoring of Atopic Dermatitis (SCORAD) index on admission and at discharge. Serum levels of eosinophil cationic protein and mast cell tryptase were determined in parallel both on admission and at discharge. After a mean treatment period of 24+/-12 days a decrease in the SCORAD index from 47.6+/-19.5 to 7.7+/-8.2 was achieved (p<0.001). Serum levels of eosinophil cationic protein decreased from 22.8+/-19.7 microg/l to 15.4+/-17.5 microg/l, whereas serum tryptase levels did not change. However, there was no significant correlation between the changes in SCORAD, eosinophil cationic protein and tryptase in our cohort. Thus, routine determination of serum eosinophil cationic protein or tryptase levels, in addition to evaluation of disease activity using the SCORAD index, is not recommended in unselected patients with atopic dermatitis.
...
PMID:Comparison of severity scoring of atopic dermatitis values and serum levels of eosinophil cationic protein and mast cell tryptase for routine evaluation of atopic dermatitis. 1102 63

Oranges are suspected of inducing adverse skin reactions in patients with atopic eczema. We studied 21 adult patients with atopic eczema and a history of adverse reactions to oranges and 10 patients without. A dietary history, skin tests, serum IgE and oral provocation tests with oranges were obtained. Severity of eczema was monitored by SCORAD, and serum tryptase, eosinophil cationic protein and urinary methylhistamine were measured. No allergic reactions were found to orange in skin prick or patch tests. However, 23 patients (74%) had specific serum IgE to orange. Oral provocation testing resulted in pruritic eczematous or maculopapular skin lesions predominantly at the predilection sites in 16 patients (52%). The SCORAD increased significantly in patients positive to the oral provocation test (p <0.05). Specific IgE to orange did not correlate with the clinical outcome of the oral provocation test. No significant changes were found in serum mast cell tryptase, eosinophil cationic protein or in urinary methylhistamine excretion. The negative results in the skin tests and a lack of correlation between specific IgE and oral provocation tests indicate that non-IgE-mediated mechanisms are involved in cutaneous adverse reactions to oranges in patients with atopic eczema.
...
PMID:Orange-induced skin lesions in patients with atopic eczema: evidence for a non-IgE-mediated mechanism. 1263 22

Inhibitors of human mast cell tryptase (EC 3.4.21.59) have therapeutic potential for treating allergic or inflammatory disorders. We have investigated transition-state mimetics possessing a heterocycle-activated ketone group and identified in particular benzothiazole ketone (2S)-6 (RWJ-56423) as a potent, reversible, low-molecular-weight tryptase inhibitor with a K(i) value of 10 nM. A single-crystal X-ray analysis of the sulfate salt of (2S)-6 confirmed the stereochemistry. Analogues 12 and 15-17 are also potent tryptase inhibitors. Although RWJ-56423 potently inhibits trypsin (K(i) = 8.1 nM), it is selective vs other serine proteases, such as kallikrein, plasmin, and thrombin. We obtained an X-ray structure of (2S)-6 complexed with bovine trypsin (1.9-A resolution), which depicts inter alia a hemiketal involving Ser-189, and hydrogen bonds with His-57 and Gln-192. Aerosol administration of 6 (2R,2S; RWJ-58643) to allergic sheep effectively antagonized antigen-induced asthmatic responses, with 70-75% blockade of the early response and complete ablation of the late response and airway hyperresponsiveness.
...
PMID:Potent, small-molecule inhibitors of human mast cell tryptase. Antiasthmatic action of a dipeptide-based transition-state analogue containing a benzothiazole ketone. 1293 Jan 48

Mast cells may participate actively in the inflammatory process of atherosclerotic plaques by releasing proteolytic enzymes and various other pro-inflammatory substances. We hypothesized that increased levels of mast cell tryptase, could be an important biomarker in patients with stable coronary artery disease (CAD). We measured tryptase in 102 patients without acute coronary syndromes undergoing cardiac catheterization. Patients with significant CAD [> or =50% stenosis in > or =1 artery (n=66)] had significantly higher serum tryptase than patients with normal angiography (n=13) or non-significant CAD [<50% stenosis (n=23)]. The median, 25th and 75th percentiles for tryptase in these two groups were 8.38 (6.4 and 10.7)mug/L versus 6.78 (5.61 and 9.72) microg/L, p=0.014. Patients in the highest quartile of tryptase levels had a 4.3-fold risk for CAD [Odds ratio (OR): 4.3; 95% confidence interval (CI): 1.08-17.19; p=0.04]. In a multivariate regression analysis, tryptase remained an independent predictor for CAD along with age (OR: 1.178; 95% CI: 1.021-1.359, p=0.025). High circulating tryptase levels may be a result of chronic low-grade inflammatory activity present in atherosclerotic plaques. Tryptase measurements may emerge as a novel way of identifying asymptomatic patients with CAD, and represent a new biomarker of therapeutic efficacy in patients with CAD.
...
PMID:Mast cell tryptase: a new biomarker in patients with stable coronary artery disease. 1569 48

Proteases function at every level in host defense, from regulating vascular hemostasis and inflammation to mobilizing the "rapid responder" leukocytes of the immune system by regulating the activities of various chemoattractants. Recent studies implicate proteolysis in the activation of a ubiquitous plasma chemoattractant, chemerin, a ligand for the G-protein-coupled receptor CMKLR1 present on plasmacytoid dendritic cells and macrophages. To define the pathophysiologic triggers of chemerin activity, we evaluated the ability of serum- and inflammation-associated proteases to cleave chemerin and stimulate CMKLR1-mediated chemotaxis. We showed that serine proteases factor XIIa and plasmin of the coagulation and fibrinolytic cascades, elastase and cathepsin G released from activated neutrophil granules and mast cell tryptase are all potent activators of chemerin. Activation results from cleavage of the labile carboxyl terminus of the chemoattractant at any of several different sites. Activation of chemerin by the serine protease cascades that trigger rapid defenses in the body may direct CMKLR1-positive plasmacytoid dendritic cell and tissue macrophage recruitment to sterile sites of tissue damage, as well as trafficking to sites of infectious and allergic inflammation.
...
PMID:Chemerin activation by serine proteases of the coagulation, fibrinolytic, and inflammatory cascades. 1609 70

Profound hypotension and cardiac arrest after commencement of combined spinal and general anaesthesia in a patient for knee replacement surgery raised the suspicion of anaphylaxis. This seemed to be confirmed when a mast cell tryptase test taken about 90 minutes after the onset of the hypotension was elevated. However, subsequent intradermal skin testing twelve weeks later did not identify a causal drug. Repeat mast cell tryptase at the time showed the same elevation, which led to the correct diagnosis of mastocytosis and a secondary diagnosis that the patient's hypotension and cardiac arrest were the result of her spinal anaesthesia. If the serum tryptase is elevated during the event but no allergic agent can be identified, a further serum tryptase should be taken several weeks later to exclude a persistent elevation due to mastocytosis.
...
PMID:Pseudoanaphylaxis. 1718 2


1 2 Next >>

---