Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.4 (trypsin)
 42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The role of angiotensin converting enzyme (ACE, peptidyl dipeptidase A) in metamorphic- and reproductive-related events in the Egyptian cotton leafworm, Spodoptera littoralis (Lepidoptera, Noctuidae) was studied by using the selective ACE inhibitor captopril. Although oral administration of captopril had no effect on larval growth, topical administration to new pupae resulted in a large decrease of successful adult formation. Oviposition and overall appearance of adults emerging from treated larvae did not differ significantly from those emerging from non-treated larvae. In contrast, topical or oral administration of captopril to newly emerged adults caused a reduction in oviposition. By evaluating the effect of captopril on ecdysteroid titers and trypsin activity, we revealed an additional physiological role for ACE. Captopril exerted an inhibitory effect on ecdysteroid levels in female but not in male adults. Larvae fed a diet containing captopril exhibited increased trypsin activity. A similar captopril-induced increase in trypsin activity was observed in female adults. In male adults, however, captopril elicited reduced levels of trypsin activity. Our results suggest that captopril downregulates oviposition by two independent pathways, one through ecdysteroid biosynthesis regulation, and the other through regulation of trypsin activity. Apparently, fecundity is influenced by a complex interaction of ACE, trypsin activity, and ecdysteroid levels.
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PMID:The angiotensin converting enzyme inhibitor captopril reduces oviposition and ecdysteroid levels in Lepidoptera. 1548 60

By using the selective ACE inhibitor captopril, we studied the effect of the angiotensin converting enzyme (ACE) on larval growth, metamorphosis, and reproduction in a lepidopteran species, the cotton leafworm, Spodoptera littoralis. Captopril was detrimental to adult formation and oviposition, and in female moths it elicited decreasing ecdysteroid levels, but increasing trypsin activities. Our results suggest that captopril downregulates oviposition by two independent pathways. Apparently, oviposition is influenced by a complex interaction of ACE, trypsin activity, and ecdysteroid levels.
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PMID:ACE inhibitor captopril reduces ecdysteroids and oviposition in moths. 1589 Nov

The effects of different proteolytic treatments on the physiochemical and bitterness properties of pea protein hydrolysates were investigated. A commercial pea protein isolate was digested using each of 5 different proteases to produce protein hydrolysates with varying properties. After 4 h of enzyme digestion, samples were clarified by centrifugation followed by desalting of the supernatant with a 1000 Da membrane; the retentates were then freeze-dried. Alcalase and Flavourzymetrade mark produced protein hydrolysates with significantly higher (P < 0.05) degree of hydrolysis when compared to the other proteases. Flavourzyme, papain, and alcalase produced hydrolysates that contained the highest levels of aromatic amino acids, while trypsin hydrolysate had the highest levels of lysine and arginine. Papain hydrolysate contained high molecular weight peptides (10 to 178 kDa) while hydrolysates from the other 4 proteases contained predominantly low molecular weight peptides (</= 23 kDa). DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging activity of the Flavourzyme hydrolysate was significantly (P < 0.05) the highest while alcalase and trypsin hydrolysates were the lowest. Inhibition of angiotensin converting enzyme (ACE) activity was significantly higher (P < 0.05) for papain hydrolysate while Flavourzyme hydrolysate had the least inhibitory activity. Sensory analysis showed that the alcalase hydrolysate was the most bitter while papain and alpha-chymotrypsin hydrolysates were the least. Among the 5 enzymes used in this study, papain and alpha-chymotrypsin appear to be the most desirable for producing high quality pea protein hydrolysates because of the low bitterness scores combined with a high level of angiotensin converting enzyme inhibition and moderate free radical scavenging activity.
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PMID:Physicochemical and bitterness properties of enzymatic pea protein hydrolysates. 1799 27

Mast cell tryptase plays an important role in fibrosis. Tryptase levels in bronchial alveolar lavage fluid (BALF) from patients with interstitial lung diseases are frequently increased, but little is known of the clinical significance. The study population consisted of 93 patients [38 with sarcoidosis, 23 with collagen vascular disease (CVD), and 32 with idiopathic pulmonary fibrosis (IPF)]. BALF tryptase levels were measured with a newly developed B12 antibody-fluoroimmunocap method (UniCAP method), which can detect an activated form of tryptase. We examined the relationship between BALF tryptase levels and clinical parameters of the diseases. BALF tryptase was detected in 7 (18.4%) patients with sarcoidosis, 7 (30.4%) with CVD, and 14 (45.8%) with IPF. In tryptase-positive group, serum ACE levels and the numbers of BALF-mast cells and lymphocytes were higher than the tryptase-negative group in sarcoidosis, serum LDH levels were higher in CVD, and the number of BALF-lymphocyte and Hugh-Jones grade were higher in IPF. Furthermore, tryptase-positive IPF cases had a poorer outcome than the tryptase-negative group by Kaplan-Meier analysis. Tryptase in BALF detected with the UniCAP method may be associated with disease activity in sarcoidosis and CVD, and with severity and poor prognosis in IPF. BALF tryptase measurement may be useful in the assessment of disease activity and severity in various interstitial lung diseases.
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PMID:[The clinical significance of mast cell tryptase in bronchial alveolar lavage fluid in interstitial lung diseases]. 1805 86

This study was aimed at the search of urinary biomarkers which might help to predict the clinical response of IgA nephropathy (IgAN) patients to angiotensin converting enzyme inhibitors (ACEi). First, we studied the urinary proteome of 18 IgAN patients (toward 20 healthy controls) who had been chronically treated with ACEi by using 2-D PAGE coupled to nano-HPLC-ESI-MS/MS analysis. We identified 3 proteins, kininogen (p = 0.02), inter-alpha-trypsin-inhibitor heavy chain 4 (35 kDa fragment) (p = 0.02) and transthyretin (p<0.0001), whose urinary excretion was different in IgAN patients' responders when compared to those who had not responded to ACEi. A reduction of daily proteinuria >50% and a stable renal function over time were used to classify patients as responders. Then, we adopted immunoblotting to confirm the predictive power of one of the above proteins, kininogen, in 20 patients with biopsy-proven IgAN, before starting any therapy. Thus, we confirmed that very low levels of kininogen urine excretion were indeed predictive of an inadequate or absent clinical response to ACEi therapy of IgAN patients, after 6-month follow-up. Concluding, the analysis of urine proteome of IgAN patients generated a set of proteins which distinguished subjects responsive to ACEi from those unresponsive to the inhibition of renin-angiotensin system (RAS).
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PMID:Urine protein profile of IgA nephropathy patients may predict the response to ACE-inhibitor therapy. 1809 57

Although LC-MS methods are increasingly used for the absolute quantification of proteins, the lack of appropriate internal standard (IS) hinders the development of rapid and standardized analytical methods for both in vitro and in vivo studies. Here, we have developed a novel method for the absolute quantification of a therapeutic protein, which is monoclonal antibody (mAb). The method combines liquid chromatography tandem mass spectrometry (LC-MS/MS) and protein cleavage isotope dilution mass spectrometry with the isotope-labeled mAb as IS. The latter was identical to the analyzed mAb with the exception that each threonine contains four (13)C atoms and one (15)N atom. Serum samples were spiked with IS prior to the overnight trypsin digestion and subsequent sample cleanup. Sample extracts were analyzed on a C18 ACE column (150 mm x 4.6 mm) using an LC gradient time of 11 min. Endogenous mAb concentrations were determined by calculating the peak height ratio of its signature peptide to the corresponding isotope-labeled peptide. The linear dynamic range was established between 5.00 and 1000 microg/mL mAb with accuracy and precision within +/-15% at all concentrations and below +/-20% at the LLOQ (lower limit of quantification). The overall method recovery in terms of mAb was 14%. The losses due to sample preparation (digestion and purification) were 72% from which about 32% was due to the first step of the method, the sample digestion. This huge loss during sample preparation strongly emphasizes the necessity to employ an IS right from the beginning. Our method was successfully applied to the mAb quantification in marmoset serum study samples, and the precision obtained on duplicate samples was, in most cases, below 20%. The comparison with enzyme-linked immunosorbent assay (ELISA) showed higher exposure in terms of AUC and Cmax with the LC-MS/MS method. Possible reasons for this discrepancy are discussed in this study. The results of this study indicate that our LC-MS/MS method is a simple, rapid, and precise approach for the therapeutic mAb quantification to support preclinical and clinical studies.
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PMID:Towards absolute quantification of therapeutic monoclonal antibody in serum by LC-MS/MS using isotope-labeled antibody standard and protein cleavage isotope dilution mass spectrometry. 1846 83

Silkworm pupae protein is a good source of high quality protein. The hydrolyzates of silkworm pupae protein catalyzed by neutrase, pepsin, acidic protease (Asperqiius usamii NO. 537), flavourzyme, alcalase, and trypsin with inhibitory activity on angiotensin I-converting enzyme (ACE) were identified by HPLC. The hydrolyzates catalyzed by acidic protease exerted the highest inhibitory activity on ACE. The hydrolyzing conditions were optimized by one-factor, factional factorial (FFD), and center composite (CCD) design methods, and response surface methodology (RSM). Statistical analyses showed that regression of the second-order model equation is suitable to describe ACE inhibitory bioactivity. The predicted inhibitory activity of hydrolyzates on ACE was 73.5 % at a concentration of 2.0 mg/ml. Optimized RSM technique decreased IC(50) of hydrolyzates inhibiting ACE to 1.4 mg/mL from 2.5 mg/ml. The molecular weight of the components of the hydrolyzates with inhibitory activity on ACE varied from less than 500 to about 1000 Da by ultra-filter analysis. These studies suggest that hydrolyzates of silkworm protein contain ACE inhibitory activity that could form a potential source of ACE inhibitor drugs.
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PMID:Hydrolyzates of silkworm pupae (Bombyx mori) protein is a new source of angiotensin I-converting enzyme inhibitory peptides (ACEIP). 1869 Oct 90

We found human renin inhibitory activity in soybean and isolated the active compound, soybean renin inhibitor (SRI). The physico-chemical data on the isolated SRI were identical with those of soyasaponin I. SRI showed significant inhibition against recombinant human renin, with an IC(50) value of 30 microg/ml. Kinetic studies with SRI indicated partial noncompetitive inhibition, with a K(i) value of 37.5 microM. On the other hand, SRI weakly inhibited pepsin, papain, and bromeline activities, but did not inhibit other proteinases, such as trypsin, kallikrein, angiotensin converting enzyme, and aminopeptidase M. Moreover, a significant (p<0.05) decrease in the systolic blood pressure of spontaneously hypertensive rats was observed when partially purified SRI was orally administrated at 40 mg/kg/d for 7 weeks. This is the first demonstration of a renin inhibitor from soybean, soyasaponin I.
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PMID:Isolation of human renin inhibitor from soybean: soyasaponin I is the novel human renin inhibitor in soybean. 1906 Apr 6

The interactions of 2, 4-dinitrophenol and 2, 4-dichlorphenol with trypsin were investigated by fluorescence, synchronous fluorescence, and three-dimensional fluorescence spectra techniques under physiological pH 7.40. The 2, 4-dinitrophenol and 2, 4-dichlorphenol effectively quenched the intrinsic fluorescence of trypsin via static quenching. The process of binding 2, 4-dinitrophenol and 2, 4-dichlorphenol with trypsin was a spontaneous molecular interaction procedure. The electrostatic repulsion does favor the interaction between 2, 4-DNP and trypsin. However, the interaction of 2, 4-DCP and trypsin can be explained on the basis of hydrogen bonding and van der Waals. The results of synchronous fluorescence spectroscopy and three-dimensional fluorescence spectra indicated that the structure of these trytophan and tyrosine residues environments were altered by 2, 4-DNP and 2, 4-DCP.
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PMID:Studies on the interactions of 2, 4-dinitrophenol and 2, 4-dichlorphenol with trypsin. 2003 66

Amaranth seed proteins have a better balance of essential amino acids than cereals and legumes. In addition, the tryptic hydrolysis of amaranth proteins generates, among other peptides, angiotensin converting enzyme (ACE) inhibitory (ACEi) peptides. ACE converts angiotensin I (Ang I) into Ang II, but is also responsible for the degradation of bradykinin (BK). In contrast to Ang II, BK stimulates vasodilation modulated through endothelial nitric oxide (NO) production. The aim of the present study was to characterize the ACEi activity of amaranth trypsin-digested glutelins (TDGs) and their ability to induce endothelial NO production. An IC(50) value of 200microgml(-1) was measured for TDG inhibition of ACE. TDGs stimulated endothelial NO production in coronary endothelial cells (CEC) by 52% compared to control. The effects of TDGs were comparable to those of BK and Captopril, both used as positive controls of NO production. Consistent with these effects, TDGs induced, in a dose-dependent manner, endothelial NO-dependent vasodilation in isolated rat aortic rings. These results suggest that TDGs induce endothelial NO production and consequent vasodilation through their ACEi activity. Amaranth TDGs have a high potential as a nutraceutical food in prevention of cardiovascular diseases. Further molecular, cellular and physiological studies are currently under way and the results may contribute to a better understanding and control of cardiovascular disorders.
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PMID:Tryptic amaranth glutelin digests induce endothelial nitric oxide production through inhibition of ACE: antihypertensive role of amaranth peptides. 2043 55


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