Navegando por Palavras-chave "kininogen"
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- ItemSomente MetadadadosCaiman crocodilus yacare plasma kininogen detection(Elsevier B.V., 1996-05-01) Araujo, M. S.; Andreotti, R.; Tiaen, M.; Nunes, V; Oliva, M. L.; Sampaio, M.; Iimura, O.; Shimamoto, K.; Ura, N.; Sampaio, C.; Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA); SAPPORO MED UNIV; Universidade Federal de São Paulo (UNIFESP)
- ItemSomente MetadadadosComparative substrate specificity analysis of recombinant human cathepsin V and cathepsin L(Elsevier B.V., 2004-10-15) Puzer, L.; Cotrin, S. S.; Alves, MFM; Egborge, T.; Araujo, M. S.; Juliano, M. A.; Juliano, L.; Bromme, D.; Carmona, A. K.; Universidade Federal de São Paulo (UNIFESP); Mt Sinai Sch MedCathepsins V and L have high identity and few structural differences. in this paper, we reported a comparative study of the hydrolytic activities of recombinant human cathepsins V and L using fluorescence resonance energy transfer peptides derived from Abz-KLRSSKQ-EDDnp (Abz = ortho-aminobenzoic acid and EDDnp = N-(2,4-dinitrophenyl)ethylenediamine). Five series of peptides were synthesized to map the S-3 to S'(2) subsites. the cathepsin V subsites S-1 and S-3 present a broad specificity while cathepsin L has preference for positively charged residues. the S-2 subsites of both enzymes require hydrophobic residues with preference for Phe and Leu. the S-1' and S-2' subsites of cathepsins V and L are less specific. Based on these data we designed substrates to explore the electrostatic potential differences of them. Finally, the kininogenase activities of these cathepsins were compared using synthetic human kininogen fragments. Cathepsin V preferentially released Lys-bradykinin while cathepsin L released bradykinin. This kininogenase activity by cathepsins V and L was also observed from human high and low molecular weight kininogens. (C) 2004 Elsevier Inc. All rights reserved.
- ItemSomente MetadadadosThe fate of plasma kallikrein in normal and kininogen-deficient rats(Swets Zeitlinger Publishers, 1998-02-01) Kouyoumdjian, M.; Damas, J.; Univ Liege; Universidade Federal de São Paulo (UNIFESP)The clearance of exogenous plasma kallikrein, its uptake by liver, spleen, kidneys, lungs and its extravasation in the paws were determined in normal Wistar rats, normal and kininogen-deficient Brown Norway rats. Kallikrein was purified from rat plasma and labelled with I-125. After intravenous injection of I-125-kallikrein, the disappearance of acid-precipitable kallikrein from the blood fits a biexponential curve similar in the three groups of rats: a rapid initial clearance (T-1/2 around 3 min) followed by a phase of slower elimination (T-1/2 around 50 min). Removal of kallikrein from the blood was associated with a large uptake of radioactivity by the liver: 67% of the I-125-kallikrein cleared from the blood at 10 min. the kidneys and the spleen accumulated small amounts of the radioactivity. the uptake of kallikrein by the spleen was slightly reduced in kininogen-deficient rats. the kininogen deficiency in Brown Norway rats from the strain BN/May Pfd was confirmed by the low levels of kinins released by tissue kallikrein and by a prolongation of activated thromboplastin times in the plasma of these animals. We concluded that plasma kallikrein is rapidly cleared from the circulation of the rat. the liver is the main clearing organ of plasma kallikrein. the disappearance of kallikrein from the circulation is not affected by the lack of high molecular weight kininogen, except in the case of the uptake of the enzyme performed by the cells of the spleen, which is reduced.
- ItemSomente MetadadadosFunctional, biochemical, and molecular investigations of renal kallikrein-kinin system in diabetic rats(Amer Physiological Soc, 1999-12-01) Tschope, C.; Reinecke, A.; Seidl, U.; Yu, M.; Gavriluk, V; Riester, U.; Gohlke, P.; Graf, K.; Bader, M.; Hilgenfeldt, U.; Pesquero, João Bosco [UNIFESP]; Ritz, E.; Unger, T.; Free Univ Berlin; Univ Kiel; Univ Heidelberg; Max Delbruck Ctr Mol Med; Humboldt Univ; Universidade Federal de São Paulo (UNIFESP)A reduction of renal kallikrein has been found in non-insulin-treated diabetic individuals, suggesting that an impaired renal kallikreinkinin system (KKS) contributes to the development of diabetic nephropathy. We analyzed relevant components of the renal KKS in non-insulin-treated streptozotocin (STZ)-induced diabetic rats. Twelve weeks after a single injection of STZ, rats were normotensive and displayed hyperglycemia, polyuria, proteinuria, and reduced glomerular filtration rate. Blood bradykinin (BK) levels and prekallikrein activity were significantly increased compared with controls. Renal kallikrein activity was reduced by 70%, whereas urinary BK levels were increased up to threefold. Renal kininases were decreased as indicated by a 3-fold reduction in renal angiotensin-converting enzyme activity and a 1.8-fold reduction in renal expression of neutral endopeptidase 24.11. Renal cortical expression of kininogen and Bg receptors was enhanced to 1.4 and 1.8-fold, respectively Our data suggest that increased urinary BK levels found in severely hyperglycemic STZ-diabetic rats are related to increased filtration of components of the plasma KKS and/or renal kininogen synthesis in combination with decreased renal kinin-degrading activity. Thus, despite reduced renal kallikrein synthesis, renal KKS is activated in the advanced stage of diabetic nephropathy.
- ItemSomente MetadadadosGenetic analysis of hereditary angioedema in a Brazilian family by targeted next generation sequencing(Walter De Gruyter Gmbh, 2016) Veronez, Camila Lopes [UNIFESP]; Silva, Elton Dias da [UNIFESP]; Teixeira, Patricia Varela Lima [UNIFESP]; Cagini, Nathalia [UNIFESP]; Constantino-Silva, Rosemeire Navickas; Grumach, Anete Sevciovic; Mansour, Eli; Velloso, Licio A.; Pesquero, João Bosco [UNIFESP]Hereditary angioedema (HAE) is accompanied by an overproduction of bradykinin (BK) as the primary mediator of swelling. Although many proteins may be involved in regulating the wide spectrum of HAE symptoms, most studies have only focused on C1-INH and FXII. For the first time, a next generation sequencing (NGS) method was applied to develop a robust, time- and cost-effective diagnostic and research tool to analyze selected genes related to HAE. The entire coding region and the exon-intron boundaries of 15 genes from 23 subjects of a Brazilian family, nine of whom were symptomatic, were analyzed by NGS. One new mutation found uniquely in the nine symptomatic patients, p.Ala457Pro in the SERPING1 gene, was estimated as likely to be pathogenic -(PolyPhen-2 software analysis) and is the main candidate to be responsible for HAE in these patients. Alterations identified in a few asymptomatic individuals but also found in almost all symptomatic patients, such as p.Ile197Met (HMWK), p. Glu298Asp (NOS3) and p.Gly354Glu (B2R), may also be involved in modulating patient-specific symptoms. This NGS gene panel has proven to be a valuable tool for a quick and accurate molecular diagnosis of HAE and efficient to indicate modulators of HAE symptoms.
- ItemSomente MetadadadosGenetically altered animal models in the kallikrein-kinin system(Walter de Gruyter & Co, 2006-02-01) Pesquero, J. B.; Bader, M.; Max Delbruck Ctr Mol Med; Universidade Federal de São Paulo (UNIFESP)Transgenic and gene-targeting technologies allowing the generation of genetically altered animal models have greatly advanced our understanding of the function of specific genes. This is also true for the kallikrein-kinin system (KKS), in which some, but not yet all, components have been functionally characterized using such techniques. the first genetically altered animal model for a KKS component was supplied by nature, the brown Norway rat carrying an inactivating mutation in the kininogen gene. Mice deficient in tissue kallikrein, B1 and B2 receptors, some kinin-degrading enzymes, and factor XII followed, together with transgenic rat and mouse strains overexpressing tissue kallikrein, B1 and B2 receptors, and degrading enzymes. There are still no animal models with genetic alterations in plasma kallikrein, kininases I and some other degrading enzymes. the models have confirmed an important role of the KKS in cardiovascular pathology, inflammation, and pain, and have partially elucidated the distinct function of the two receptors. This created the basis for rational decisions concerning the putative use of kinin receptor agonists and antagonists in therapeutic applications. However, a more thorough analysis of the existing models and the generation of new, more sophisticated transgenic models will be necessary to clarify the still elusive issue as to where and by which mechanisms the kinins exert their actions.
- ItemSomente MetadadadosKininogen-derived fluorogenic substrates for investigating the vasoactive properties of rat tissue kallikreins - Identification of a T-kinin-releasing rat kallikrein(Springer, 1997-07-15) ElMoujahed, A.; BrillardBourdet, M.; Juliano, M. A.; Moreau, T.; Chagas, JR; Gutman, N.; Prado, E. S.; Gauthier, F.; UNIV TOURS; Universidade Federal de São Paulo (UNIFESP)Peptide substrates with intramolecularly quenched fluorescence that reproduce the rat kininogen sequences at both ends of the bradykinin moiety were synthesized and used to investigate the kinin-releasing properties of five rat tissue kallikreins (rK1, rK2, rK7, rK9, rK10). Substrates derived from rat H- and L-kininogen were cleaved best by rK1, especially that including the N-terminal insertion site of bradykinin; Abz-TSVIRRPQ-EDDnp(Abz = O-aminobenzoyl, EDDnp = ethylenediamine 2,4-dinitrophenyl), which was cleaved at the R-R bond with a k(cat)/k(m) of 12 400 mM(-1) s(-1). Replacement of the P2' residue Pro by Val in Abz-TSVIRRPQ-EDDnp gave a far less specific substrate that was rapidly hydrolysed by all five rat kallikreins and human kallikrein hK1. Peptidyl-N-methyl coumarylamide substrates, which lack prime residues, also had low specificities. The importance of the P2' residue for rK1 specificity was further demonstrated using a human-kininogen-derived substrate that included the N-terminal insertion site of bradykinin (Abz-LMKRP-EDDnp). This was cleaved at the M-K bond by hK1 (kallidin-releasing site), but at the K-R bond (bradykinin-releasing site) by rK1. Competition experiments, with Abz-TSVIRRPQ-EDDnp. which is resistant to most kallikreins. and Abz-TSVIRRVQ-EDDnp. a general kallikrein substrate. demonstrated that the former competitively inhibited hydrolysis by rK9 and hK1, with K-i values similar to the K-m, values for the substrate. Thus Pro in P2' does not prevent the peptide binding to the enzyme active site, but impairs cleavage of the scissile bond. The T-kininogen-derived substrate with the T-kinin C-terminal sequence (Abz-FRLVR-EDDnp) was cleaved by rK10 (k(cat)/K-m = 2310 mM(-1) s(-1)) and less rapidly by rK1, rK7 and hK1, at the R-L bond, while that corresponding to the N-terminal (Abz-ALDMMISRP-EDDnp) of T-kinin was resistant to all five kallikreins used, suggesting that none has T-kininogenase activity. But this substrate was hydrolysed by a semi-purified sample of submandibular gland extract. Another kallikrein, identified as kallikrein rK3, was isolated from this fraction and shown to hydrolyze Abz-ALDMMISRP-EDDnp: rK3 also specifically released T-kinin from purified T1/T2-kininogen after HPLC fractionation. Injection of purified rK3 and of Abz-ALDMMISRP-EDDnp-cleaving fractions into the circulation of anesthesized rats caused transient falls in blood pressure, as did purified rK1 but none of the other purified rat or human kallikreins. This effect occurred via activation of the kinin system since it was blocked by Hoe140, a kinin receptor antagonist.
- ItemAcesso aberto (Open Access)Modulation of the Plasma Kallikrein-Kinin System Proteins Performed by Heparan Sulfate Proteoglycans(Frontiers Media Sa, 2017) Motta, Guacyara [UNIFESP]; Tersariol, Ivarne L. S. [UNIFESP]Human plasma kallikrein-kinin system proteins are related to inflammation through bradykinin. In the proximity of its target cells, high molecular weight kininogen (H-kininogen) is the substrate of plasma kallikrein, which releases bradykinin from H-kininogen. Heparan sulfate proteoglycans (HSPGs) play a critical role in either recruiting kinin precursors from the plasma, or in the assembly of kallikrein-kinin system components on the cell surface. Furthermore, HSPGs mediate the endocytosis and activation of H-kininogen and plasma prekallikrein. In the presence of HSPGs (Chinese hamster ovary cell, CHO-K1, wild type cells) both heparin and heparan sulfate strongly inhibit the H-kininogen interaction with the cell membrane. H-kininogen is internalized in endosomal acidic vesicles in CHO-K1 but not in CHO-745 cells (mutant cells deficient in glycosaminoglycan biosynthesis). The endocytosis process is lipid raft-mediated and is dependent on caveolae. Both types of CHO cells do not internalize bradykinin-free H-kininogen. At pH 7.35, bradykinin is released from H-kininogen on the surface of CHO-745 cells only by serine proteases
- ItemSomente MetadadadosA possible alternative mechanism of kinin generation in vivo by cathepsin L(Walter de Gruyter & Co, 2005-07-01) Puzer, L.; Vercesi, J.; Alves, MFM; Barros, NMT; Araujo, M. S.; Juliano, M. A.; Reis, M. L.; Juliano, L.; Carmona, A. K.; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)We investigated the ability of cathepsin L to induce a hypotensive effect after intravenous injection in rats and correlated this decrease in blood pressure with kinin generation. Simultaneously with blood pressure decrease, we detected plasma kininogen depletion in the treated rats. the effect observed in vivo was abolished by preincubation of cathepsin L with the cysteine peptidase-specific inhibitor E-64 (11 mu m) or by previous administration of the bradykinin B-2 receptor antagonist JE049 (4 mg/kg). A potentiation of the hypotensive effect caused by cathepsin L was observed by previous administration of the angiotensin I-converting enzyme inhibitor captopril (5 mg/kg). in vitro studies indicated that cathepsin L excised bradykinin from the synthetic fluorogenic peptide Abz-MTSVIRRPPGFSPFRAPRV-NH2, based on the Met(375)-Val(393) sequence of rat kininogen (Abz=o-aminobenzoic acid). in conclusion, our data indicate that in vivo cathepsin L releases a kinin-related peptide, and in vitro experiments suggest that the kinin generated is bradykinin. Although it is well known that cysteine proteases are strongly inhibited by kininogen, cathepsin L could represent an alternative pathway for kinin production in pathological processes.
- ItemSomente MetadadadosSpecificity of S '(1) and S '(2) subsites of human tissue kallikrein using the reactive-centre loop of kallistatin: the importance of P '(1) and P '(2) positions in design of inhibitors(Portland Press, 2003-05-01) Pimenta, Daniel C. [UNIFESP]; Fogaca, Sandro E.; Melo, Robson L.; Juliano, Luiz [UNIFESP]; Juliano, Maria Aparecida [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)We have demonstrated that the S-1' and S-2', subsites of human tissue kallikrein (hK1) play determinant roles in the recognition and hydrolysis of substrates. the presence of serine at position P-1' and arginine at P-2' resulted in the best substrate, Abz-Ala-Ile-Lys-Phe-Phe-Ser-Arg-Gln-EDDnp, which was derived from the kallistatin reactive-centre loop sequence and quencher groups o-aminobenzoic acid (Abz) and N-(2,4-dinitrophenyl)ethylenediamine (EDDnp). Serine and arginine are also the residues at positions P-1' and P-2' in human kininogen, from which hK1 releases Lys-bradykinin. Several peptide analogues of Abz-Ala-Ile-Lys-Phe-Phe-Ser-Arg-Gln-EDDnp, in which the Ser and Arg residues were substituted with various other amino acids, were synthesized and tested as substrates. Most of them were hydrolysed slowly, although they showed significant binding to hK1, as demonstrated by their competitive inhibition constants (K-i). Using this information, six peptides were designed, synthesized and assayed as inhibitors of hK1. Abz-Lys-Phe-Phe-Pro-Arg-Gln-EDDnp, Abz-Lys-Phe-Arg-Pro-Arg-Gln-EDDnp and acetyl-Lys-Phe-Phe-Pro-Leu-Glu-NH2 inhibited hK1 in the range 20-30 nM (letters in italics denote the D-form of the amino acid). the peptide acetyl-Lys-Phe-Phe-Pro-Leu-Glu-NH2 was a weak inhibitor for other serine proteases, as indicated by the higher K-i values compared with hK1, but this peptide was a potent inhibitor of human plasma kallikrein, which has a Ki value of 8 nM. This result was surprising, since this enzyme is known to be a restricted arginyl-hydrolase. in conclusion, acetyl-Lys-Phe-Phe-Pro-Leu-Glu-NH2 can be used as a leader compound to design specific inhibitors for hK1, plasma kallikrein, or for both at same time, if the inhibition of kinin release is the main goal.