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1.
J Am Heart Assoc ; 10(7): e019961, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33759549

RESUMO

Background Corin is a transmembrane protease that activates ANP and BNP (atrial and B-type natriuretic peptides). Impaired corin expression and function are associated with heart failure. In this study, we characterized a soluble form of corin (sCorin) and examined its effects on cardiac morphology and function in mouse heart failure models. Methods and Results sCorin, consisting of the full-length extracellular fragment of human corin with an engineered activation site, was expressed in Chinese hamster ovary cells, purified from the conditioned medium with affinity chromatography, and characterized in pro-ANP processing assays in vitro and pharmacokinetic studies in mice. Effects of sCorin on mouse models of heart failure induced by left coronary artery ligation and transverse aortic constriction were assessed by ELISA analysis of plasma markers, histologic examination, and echocardiography. We showed that purified and activated sCorin converted pro-ANP to ANP that stimulated cGMP production in cultured cells. In mice, intravenously and intraperitoneally administered sCorin had plasma half-lives of 3.5±0.1 and 8.3±0.3 hour, respectively. In the mouse heart failure models, intraperitoneal injection of sCorin increased plasma ANP, BNP, and cGMP levels; lowered plasma levels of NT-proANP (N-terminal-pro-ANP), angiotensin II, and aldosterone; reduced cardiac hypertrophy and fibrosis; and improved cardiac function. Conclusions We show that sCorin treatment enhanced natriuretic peptide processing and activity, suppressed the renin-angiotensin-aldosterone system, and improved cardiac morphology and function in mice with failing hearts.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Miocárdio/metabolismo , Serina Endopeptidases/farmacocinética , Função Ventricular Esquerda/fisiologia , Animais , Fator Natriurético Atrial/metabolismo , Western Blotting , Cricetinae , Modelos Animais de Doenças , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Peptídeo Natriurético Encefálico/metabolismo , Proteínas Recombinantes/farmacocinética , Função Ventricular Esquerda/efeitos dos fármacos
2.
Antivir Ther ; 23(7): 555-566, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29927386

RESUMO

BACKGROUND: This double-blind, first-in-human Phase I study evaluated pharmacokinetics, safety and tolerability of AL-794 (prodrug of ALS-033719), a potent endonuclease inhibitor of influenza A and B in healthy volunteers. METHODS: Healthy adult volunteers were randomized to AL-794 (50-2,000 mg single ascending doses, fasting) or placebo (5 cohorts, n=6:2 AL-794: placebo/cohort) in part 1, and AL-794 (50-600 mg multiple ascending doses, twice-daily, fed or fasted) or placebo (3 cohorts, n=8:2 AL-794: placebo/cohort) for 7 days in part 2. In part 3, 8 healthy volunteers from part 1 received 450 mg AL-794 (n=6) or placebo (n=2) following a high-fat meal. All dosing was done with an oral suspension. Blood and urine samples for pharmacokinetics were collected at scheduled times and analysed for ALS-033719 and ALS-033927 (inactive glucuronide) plasma concentrations using LC-MS/MS. RESULTS: ALS-033719 plasma concentrations increased dose proportionately up to 150 mg but less than proportionately above 150 mg. Steady-state was generally achieved by the third dose. ALS-033719 exposure increased following administration with a standard meal (19%-33%) or high-fat meal (3-3.6-fold). ALS-033927 was the major metabolite observed. Renal elimination was negligible (0.2%). Seventeen AL-794-treated healthy volunteers reported ≥1 treatment-emergent adverse event (TEAE; part 1: n=6, 24%; part 2: n=11, 69%). The most common TEAEs were headache (part 1: n=3; part 2: n=5) and dizziness (part 1: n=2; part 2: n=6). CONCLUSIONS: AL-794 up to 200 mg twice daily achieved ALS-033719 exposures which are expected to be efficacious and were generally tolerated. Further studies are planned to characterize safety and antiviral activity.


Assuntos
Antivirais/farmacocinética , Inibidores Enzimáticos/farmacocinética , Serina Endopeptidases/farmacocinética , Administração Oral , Adulto , Antivirais/efeitos adversos , Antivirais/sangue , Área Sob a Curva , Tontura/diagnóstico , Tontura/etiologia , Método Duplo-Cego , Esquema de Medicação , Endonucleases/antagonistas & inibidores , Inibidores Enzimáticos/efeitos adversos , Inibidores Enzimáticos/sangue , Jejum , Cefaleia/diagnóstico , Cefaleia/etiologia , Voluntários Saudáveis , Humanos , Influenza Humana/prevenção & controle , Masculino , Segurança do Paciente , Serina Endopeptidases/efeitos adversos , Serina Endopeptidases/sangue , Proteínas Virais/antagonistas & inibidores
3.
Int J Nanomedicine ; 10: 1625-36, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25759584

RESUMO

Z-GP-Dox, the FAPα (fibroblast activation protein-α)-based doxorubicin prodrug, demonstrates excellent tumor targeting effects and a favorable toxicokinetic profile. However, the insoluble nature of Z-GP-Dox becomes a significant barrier to drug administration, particularly when it comes to the clinical stage. Here we developed a nanomicelle system to facilitate the systemic delivery of Z-GP-Dox, and evaluated its disposition in rats following administration of the micelles using a physiologically-based pharmacokinetic model. Z-GP-Dox-loaded mixed nanomicelles (ZGD-MNs) were prepared by dispersion of an ethanol solution of Z-GP-Dox, lecithin, and sodium oleate in water. The obtained ZGD-MNs were 86.6 nm in size with a drug loading of 14.03%. ZGD-MNs were fairly stable in phosphate-buffered saline and showed satisfactory physical and chemical stability over a 2-week observation period. Accumulative drug release was more than 56% within 24 hours. Further, the physiologically-based pharmacokinetic rat model consisting of various organs (ie, heart, liver, spleen, lung, kidney, and intestine) was fitted to the experimental data following administration of ZGD-loaded cosolvent (control) or micelles. Derived partition coefficient values revealed that the nanomicelles significantly altered the biodistribution of Z-GP-Dox. Of note, drug distribution to the lung, liver, and spleen was greatly enhanced and the fold change ranged from 2.4 to 33. In conclusion, this is the first report of a mixed micelle system being a viable carrier for delivery of Z-GP-Dox. Also, the pharmacokinetic behavior of Z-GP-Dox was satisfactorily described by the physiologically-based pharmacokinetic model.


Assuntos
Doxorrubicina , Portadores de Fármacos , Gelatinases , Proteínas de Membrana , Micelas , Nanopartículas/química , Pró-Fármacos , Serina Endopeptidases , Animais , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Endopeptidases , Gelatinases/química , Gelatinases/farmacocinética , Proteínas de Membrana/química , Proteínas de Membrana/farmacocinética , Pró-Fármacos/química , Pró-Fármacos/farmacocinética , Pró-Fármacos/farmacologia , Ratos , Serina Endopeptidases/química , Serina Endopeptidases/farmacocinética , Distribuição Tecidual
4.
Prostate ; 74(13): 1308-19, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25053236

RESUMO

BACKGROUND: As carcinoma progresses, the stroma undergoes a variety of phenotypic changes, including the presence of carcinoma-associated fibroblasts (CAFs) that express fibroblast activation protein (FAP). FAP is a post-prolyl endopeptidase whose expression in a healthy adult is largely restricted to the cancer-associated stroma. FAP-targeted prodrugs with a 100-fold greater therapeutic window over the parent compound were previously generated. METHODS: Prodrugs and non-cleavable controls were incubated in the presence of FAP. Plasma and tumor half-lives (t1/2) of the full-length and active forms of the prodrugs were determined using LCMS. Biodistribution studies of prodrug activation were performed. Histopathological analysis of tissues from treated animals were compared to vehicle-treated controls. Toxicity and efficacy studies were performed in human breast (MDA-MB-231 and MCF-7) and prostate (LNCaP) cancer xenografts models. RESULTS: These FAP-activated prodrugs have a significantly slower clearance from tumor tissue than the circulation (∼12 vs. ∼4.5 hr). Micromolar concentrations of active drug persist in the tumor. Active drug is detected in non-target tissues; however, histopathologic evaluation reveals no evidence of drug-induced toxicity. A FAP-activated prodrug (ERGETGP-S12ADT) inhibits tumor growth in multiple human breast and prostate cancer xenograft models. The anti-tumor effect is comparable to that observed with docetaxel, but results in significantly less toxicity. CONCLUSION: FAP-activated prodrugs are a viable strategy for the management of prostate and other cancers. These prodrugs exhibit less toxicity than a commonly used chemotherapeutic agent. Further refinement of the FAP cleavage site for greater specificity may reduce prodrug activation in non-target tissues and enhance clinical benefit.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/farmacocinética , Gelatinases/farmacocinética , Proteínas de Membrana/farmacocinética , Pró-Fármacos/farmacocinética , Neoplasias da Próstata/tratamento farmacológico , Serina Endopeptidases/farmacocinética , Adenocarcinoma/patologia , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Endopeptidases , Gelatinases/efeitos adversos , Gelatinases/uso terapêutico , Humanos , Masculino , Proteínas de Membrana/efeitos adversos , Proteínas de Membrana/uso terapêutico , Camundongos , Pró-Fármacos/efeitos adversos , Pró-Fármacos/uso terapêutico , Neoplasias da Próstata/patologia , Serina Endopeptidases/efeitos adversos , Serina Endopeptidases/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
5.
J Nanosci Nanotechnol ; 13(1): 178-83, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23646714

RESUMO

Stealth cationic liposomes (SCLs) modified with tumor-targeting single-chain fragment variable (scFV) antibody for systemic delivery of recombinant methioninase (rMETase) for gastric cancer were prepared successfully. These functional SCL nanoparticles are composed of cationic lipids, dioleoylphosphatidylethanolamine, and distearoylphosphatidylethanolamine-polyethylene glycol, which have lower gene transfection efficiencies compared with Lipofectamine 2000, and can also be used as effective gene delivery vectors. Increased therapeutic efficiency of rMETase-loaded scFV-SCLs were tested in SGC-7901 cells and compared with free rMETase in solution and rMETase-loaded SCLs. In addition, scFV-SCLs (effective diameter: 185.7 nm; polydispersity index: 0.236) can significantly boost rhodamine 123 cellular accumulation in the cytoplasm. The scFV-targeted SCLs can be used as a potentially effective drug delivery system.


Assuntos
Liases de Carbono-Enxofre/administração & dosagem , Lipossomos/química , Nanocápsulas/administração & dosagem , Serina Endopeptidases/farmacocinética , Anticorpos de Cadeia Única/farmacocinética , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Liases de Carbono-Enxofre/química , Cátions , Linhagem Celular Tumoral , Difusão , Humanos , Nanocápsulas/química , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/química , Serina Endopeptidases/uso terapêutico , Anticorpos de Cadeia Única/uso terapêutico , Neoplasias Gástricas/patologia , Resultado do Tratamento
6.
J Immunoassay Immunochem ; 32(4): 296-317, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21728822

RESUMO

Pharmacokinetic data derived from assays that accurately and precisely quantitate a therapeutic drug in circulation are critical to appropriately designing suitable dosing schedules. This manuscript describes the validation and implementation of methods to quantitate a therapeutic anti-human PCSK9 monoclonal antibody in rat and monkey sera as well as immunogenicity methods to screen the possible presence of rat and monkey antibodies directed against the antibody. As soluble, endogenous PCSK9 can interfere with a PCSK9-mediated capture step in ELISA, an indirect target-capture assay was used that potentially could capture free and target-engaged therapeutic mAb. Immunogenicity assays were based on a standard bridge ELISA using the therapeutic antibody for capture and detection. Both pharmacokinetic and immunogenicity assays were implemented in preclinical studies of the therapeutic antibody. The methods presented here may enable further pharmacokinetic studies.


Assuntos
Anticorpos Monoclonais/análise , Serina Endopeptidases/análise , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacocinética , Ensaio de Imunoadsorção Enzimática/métodos , Haplorrinos , Humanos , Pró-Proteína Convertase 9 , Pró-Proteína Convertases , Ratos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Serina Endopeptidases/imunologia , Serina Endopeptidases/farmacocinética , Solubilidade
7.
Rev. neurol. (Ed. impr.) ; 50(10): 603-606, 16 mayo, 2010. ilus
Artigo em Espanhol | IBECS | ID: ibc-86667

RESUMO

Introducción. El estado epiléptico generalizado es una urgencia médica con un algoritmo terapéutico bien definido. Sin embargo, en el estado parcial, el tratamiento debe individualizarse y valorar el riesgo del tratamiento intensivo. A diferencia del estado epiléptico generalizado, el estado parcial no se considera una emergencia médica, por lo que en la elección de su tratamiento debe valorarse cuidadosamente y de modo individualizado la relación riesgo-beneficio.Caso clínico. Varón de 72 años con estado parcial secundario a lesión isquémica y refractario a tratamiento convencional, en el que se inicia tratamiento con lacosamida y se consigue su rápida reversión. Se trata del tercer caso de estado epiléptico publicado con este fármaco y del segundo en el que se emplea vía oral. Conclusión. Aunque se requieren más estudios la lacosamida podría representar una buena opción terapéutica con escasas interacciones y efectos secundarios (AU)


Introduction. Generalised epileptic status is a medical emergency with a well-defined therapeutic algorithm. Nevertheless, in the partial status, treatment must be tailored to each patient and the risk of intensive treatment has to be assessed. Unlike generalised epileptic status, partial status is not considered a medical emergency, which means that when it comes to choosing a type of treatment the risk-benefit ratio must be carefully evaluated bearing in mind the characteristics of each particular case. Case report. A 72-year-old male with partial status secondary to an ischaemic lesion which was refractory to conventional treatment; treatment was established with lacosamide and his condition was rapidly inverted. This is the third case that has been reported of epileptic status being treated with this drug and the second in which it is employed orally. Conclusions. Although further research is required, lacosamide could be a good therapeutic option with few interactions and side effects (AU)


Assuntos
Humanos , Masculino , Idoso , Estado Epiléptico/tratamento farmacológico , Convulsões/tratamento farmacológico , Serina Endopeptidases/farmacocinética , Anticonvulsivantes/farmacocinética , Espectroscopia de Ressonância Magnética , Isquemia Encefálica/tratamento farmacológico
8.
J Control Release ; 129(1): 41-8, 2008 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-18474405

RESUMO

Earthworm fibrinolytic enzyme (EFE-d, Mr 24177), a water-soluble protein, is clinically used for the management of cardiovascular diseases. However, this protein drug has a very low oral bioavailability because of its low oil/water partitioning, low membrane permeability and unstable nature in harsh gastric juice. This study explored the possibility of absorption and efficacy enhancement for EFE-d through the delivery of the water-in-oil (w/o) microemulsions. The w/o microemulsion consisting of Labrafac CC, Labrasol, Plurol Oleique CC 497 and saline (54/18/18/10, % w/w) was developed and characterized, including conductivity, viscosity, particle size and in vitro membrane permeability. The w/o microemulsion and the control solution of EFE-d were administered intraduodenally (or orally) to rats. The w/o microemulsion possessed a higher intestinal membrane permeability in vitro as well as a higher absorption and efficacy in vivo, when compared to control solution. The intraduodenal bioavailability of EFE-d for microemulsions was 208-fold higher than that of control solution and the absolute bioavailability was 17.55%. Meanwhile, there was no tissue damage of the intestinal mucosa found after oral multiple-dose administration of the EFE-d microemulsion to rats. These findings indicated that the w/o microemulsion may represent a safe and effective oral delivery system for hydrophilic bioactivity macromolecules.


Assuntos
Portadores de Fármacos , Emulsões , Fibrinolíticos/administração & dosagem , Óleos/química , Oligoquetos/enzimologia , Serina Endopeptidases/administração & dosagem , Água/química , Administração Oral , Animais , Disponibilidade Biológica , Permeabilidade da Membrana Celular , Química Farmacêutica , Composição de Medicamentos , Condutividade Elétrica , Fibrinólise/efeitos dos fármacos , Fibrinolíticos/efeitos adversos , Fibrinolíticos/química , Fibrinolíticos/isolamento & purificação , Fibrinolíticos/farmacocinética , Glicerídeos , Absorção Intestinal , Mucosa Intestinal/efeitos dos fármacos , Intubação Gastrointestinal , Masculino , Ácidos Oleicos/química , Compostos Orgânicos/química , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Serina Endopeptidases/efeitos adversos , Serina Endopeptidases/química , Serina Endopeptidases/isolamento & purificação , Serina Endopeptidases/farmacocinética , Tensoativos/química , Tecnologia Farmacêutica/métodos , Viscosidade
9.
Biochem Biophys Res Commun ; 370(4): 634-40, 2008 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-18406350

RESUMO

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a serine protease that is known to reduce hepatic low-density lipoprotein receptor (LDLR) levels and increase plasma LDL cholesterol. It is not clear, however, whether secreted PCSK9 degrades extrahepatic LDLRs. We present evidence that recombinant PCSK9, either injected intravenously into or expressed in the liver of C57BL/6 mice, significantly reduced LDLR levels in multiple extrahepatic tissues. During the initial characterization, we found that injected human recombinant PCSK9 at 30 microg/mouse had a half-life of 15 min in serum in mice. Hepatic LDLR levels were reduced within 30min and the degradation of hepatic LDLR reached the maximum 2h after the initial protein injection. Endocytosis of PCSK9 in liver occurred within 5min of protein injection and internalized PCSK9 was only barely detectable within 1h. When extrahepatic LDLRs were examined by Western blotting analysis, we found significant reductions of LDLRs in multiple extrahepatic tissues including lung, adipose and kidney along with the more dramatic reduction of LDLRs in liver. These studies were further extended using adenoviral expression of human PCSK9 in C57BL/6 mice to demonstrate that PCSK9 produced in liver impacted extrahepatic tissue LDLR levels as well. Taken together, our studies indicate that secreted PCSK9 can potentially impact extrahepatic tissue cholesterol homeostasis by regulating extrahepatic tissue LDLR levels.


Assuntos
LDL-Colesterol/metabolismo , Fígado/metabolismo , Receptores de LDL/metabolismo , Serina Endopeptidases/metabolismo , Adenoviridae/genética , Animais , Catálise , LDL-Colesterol/sangue , Humanos , Injeções Intravenosas , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pró-Proteína Convertase 9 , Pró-Proteína Convertases , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacocinética , Serina Endopeptidases/genética , Serina Endopeptidases/farmacocinética
10.
Trends Biotechnol ; 24(10): 433-4, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16934352

RESUMO

Celiac disease is caused by an immune response to the dietary protein gluten. The only available treatment is the strict exclusion of gluten from the diet; however, this is marred by the virtual omnipresence of this protein. The enzymatic degradation of gluten might become an alternative to the gluten-free diet, and recent work indicates that such approaches are getting close to being tested in clinical trials.


Assuntos
Doença Celíaca/dietoterapia , Suplementos Nutricionais , Glutens/metabolismo , Serina Endopeptidases/farmacologia , Biotransformação/fisiologia , Doença Celíaca/fisiopatologia , Cisteína Endopeptidases/administração & dosagem , Cisteína Endopeptidases/biossíntese , Cisteína Endopeptidases/farmacocinética , Cisteína Endopeptidases/farmacologia , Humanos , Prolil Oligopeptidases , Serina Endopeptidases/administração & dosagem , Serina Endopeptidases/biossíntese , Serina Endopeptidases/farmacocinética
12.
J Control Release ; 98(1): 169-77, 2004 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-15245898

RESUMO

Linking peptide functions directly to nucleic acids can be used to improve transfection. We have previously demonstrated this by sequence-specific hybridization of a bifunctional peptide nucleic acid (PNA) consisting of a nucleic acid binding moiety conjugated to a peptide. The resulting biological complex of PNA/DNA is called a Bioplex. The bifunctional PNA is continuously synthesized with one or more functional entities. For certain applications, it might be preferable to eliminate a functional entity after it has served its purpose. We have addressed this issue by adding a specific protease cleavage site to the construct. In this first approach, cathepsin L was used to cleave a linker sequence including a cathepsin L site: afrsaaq, thereby releasing the tri-peptide Arg-Gly-Asp (RGD) from the PNA anchor. In vitro and in vivo experiments showed an efficient cleavage of the peptide. Moreover, bifunctional PNA constructs were shown to retain activity of the second entity following removal of the first function. Since cathepsin L is ubiquitously expressed in eukaryotic cells and becomes active as the endosomal pH drops, inclusion of cathepsin sites makes it possible to remove functional entities in late endosomes/early lysosomes.


Assuntos
Ácidos Nucleicos Peptídicos/farmacocinética , Polímeros/farmacocinética , Serina Endopeptidases/farmacologia , Serina Endopeptidases/farmacocinética , Animais , Preparações de Ação Retardada/farmacocinética , Cinética , Camundongos , Células NIH 3T3 , Ácidos Nucleicos Peptídicos/genética , Serina Endopeptidases/genética
13.
J Appl Microbiol ; 96(5): 994-1001, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15078516

RESUMO

AIMS: To determine the haemolysins and proteases excreted by the virulent strain EO63 of Aeromonas hydrophila grown in complex media and to then fractionate and characterize them, in particular those with elastolytic activity. METHODS AND RESULTS: The amount of haemolytic and proteolytic activity in EO63 culture supernatants was dependent on the culture media used. In all media, haemolysins appeared during the phase of active growth and haemolytic activity decreased quickly thereafter, as previously described for aerolysin. In contrast, proteases were mainly released during the stationary phase. Serine protease activity in EO63 culture supernatants was four times greater than that caused by metalloproteases. Two main proteases were partially purified from EO63 culture supernatants by isoelectrophoresis: a serine protease (68 kDa) active against casein; a mixture of different protein bands (60, 44 and 31 kDa) representing a thermostable metalloprotease active against elastin and casein. This metallo-elastase was also inhibited by dithiothreitol and showed a pH optimum of 8.0. Both exoenzymes were toxic for eels at LD50 doses of 1.1 and 3.5 microg (g fish)(-1), respectively. CONCLUSIONS: A serine caseinase and a metallo-elastase may play a role in the pathogenicity of EO63 for eels. These toxins are excreted in vitro by EO63 in the ratio of 4:1 during the stationary phase of growth. Strain EO63 also produced beta-haemolysins in vitro which could correspond to aerolysin. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report on the purification of a metallo-elastase excreted by a wild-type A. hydrophila strain.


Assuntos
Aeromonas hydrophila/metabolismo , Endopeptidases/metabolismo , Proteínas Hemolisinas/metabolismo , Aeromonas hydrophila/crescimento & desenvolvimento , Caseínas/metabolismo , Meios de Cultura , Elastina/metabolismo , Eletroforese em Gel de Poliacrilamida , Endopeptidases/isolamento & purificação , Endopeptidases/farmacocinética , Concentração de Íons de Hidrogênio , Focalização Isoelétrica , Metaloproteases/metabolismo , Metaloproteases/farmacocinética , Serina Endopeptidases/metabolismo , Serina Endopeptidases/farmacocinética
14.
J Immunol Methods ; 275(1-2): 41-56, 2003 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12667669

RESUMO

The purpose of the study was to develop a rapid technique for determining the functional status of caspase activation pathways in intact lymphocytes. Proteins known to activate caspase-family cell death proteases (cytochrome c; granzyme-B; caspase-8) were introduced into human leukemia and lymphoma cell lines, as well as freshly isolated lymphocytes and leukemia cells, by electroporation. Fluorochrome-labeled proteins with a wide range of molecular weights (from 15 to 150 kDa) were used to evaluate electroporation efficiency by flow cytometry and to compare the efficiency of protein delivery using various electroporation conditions. Caspase activity was monitored using a cleavable, cell-permeable fluorogenic substrate. Conditions were identified for efficient delivery of proteins of +150 kDa into lymphoid cells. Caspase activation induced by various proteins was compared in normal and leukemic lymphocytic cells, revealing impaired caspase activation pathways in some malignant cells. We conclude that electroporation of apoptotic proteins into intact lymphoid cells can be used to contrast the status of various caspase activation pathways, thereby providing insights into the pathological defects in apoptosis regulation that exist in individual patient specimens.


Assuntos
Caspases/metabolismo , Eletroporação/métodos , Fluoresceína-5-Isotiocianato/análogos & derivados , Linfócitos/enzimologia , Proteínas/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Caspase 8 , Caspase 9 , Caspases/administração & dosagem , Caspases/farmacocinética , Bovinos , Grupo dos Citocromos c/administração & dosagem , Grupo dos Citocromos c/farmacocinética , Ativação Enzimática/efeitos dos fármacos , Citometria de Fluxo , Fluoresceína-5-Isotiocianato/administração & dosagem , Fluoresceína-5-Isotiocianato/farmacocinética , Corantes Fluorescentes/administração & dosagem , Corantes Fluorescentes/farmacocinética , Granzimas , Humanos , Técnicas In Vitro , Células Jurkat , Leucemia Linfocítica Crônica de Células B/enzimologia , Linfócitos/citologia , Peso Molecular , Proteínas/química , Proteínas/farmacocinética , Serina Endopeptidases/administração & dosagem , Serina Endopeptidases/farmacocinética , Soroalbumina Bovina/administração & dosagem , Soroalbumina Bovina/farmacocinética , Células Tumorais Cultivadas
15.
Biofizika ; 48(1): 76-83, 2003.
Artigo em Russo | MEDLINE | ID: mdl-12630119

RESUMO

The process of penetration of a proteolytic enzyme applied to the surface of burn wound into the depth of necrotic tissue was considered. The model approximation describes three factors by a series of mathematical equations: inward-directed enzyme diffusion, counter-flow filtration of interstitial fluid (exudates), and irreversible inactivation of the enzyme by specific inhibitors present in exudates. According to the model, a quasi-stationary distribution of enzymatic activity through the thickness of the necrotic layer is achieved within 3 h and persists as long as the enzyme concentration on the wound surface is constant. The enzyme activity diminishes linearly from the wound surface to the mid-part of the necrotic layer. No enzyme activity is retained in the inner mid-part of the necrotic layer completely protected by the prevalent inhibitor. The ratio of enzyme concentration on the wound surface to inhibitor concentration in the interstitial fluid is the same as the ratio of the depth of active enzyme area to the depth of the inhibitor-protected area through the necrotic layer. The dynamics of accumulation of the active enzyme in the necrotic zone and the rate of enzyme inactivation in the wound by inhibitors were described by formulas applicable for practical purposes.


Assuntos
Queimaduras/metabolismo , Serina Endopeptidases/farmacocinética , Pele/metabolismo , Queimaduras/patologia , Difusão , Modelos Biológicos , Necrose , Inibidores de Proteases/metabolismo , Serina Endopeptidases/metabolismo , Pele/patologia , Cicatrização
16.
Artigo em Russo | MEDLINE | ID: mdl-12506637

RESUMO

Current data on the characterization of bacterial serine proteases, forming the family of proteins with specific structural and functional features and secreted by type V (autotransport), are presented. The expression of many of these proteases is believed to be linked with pathogenicity of Gram negative bacteria, which necessitates their further study with a view to obtain more profound concepts. These enzymes have been shown to facilitate the bacterial colonization of the skin and mucous membranes. They are believed to be linked with the resistance of microorganisms to lysosomal proteolysis by phagocytes and their ensuing dissemination in the course of the infectious process. Serine proteases split coagulating factor V and enhance the permeability of blood vessels, thus inducing the hemorrhagic syndrome. The detailed study of serine proteases is closely linked with the prospects of the development of protease inhibiting preparations aimed at the suppression of the pathogenetic activity of proteases by their blocking or by affecting the mechanisms of their secretion.


Assuntos
Proteínas de Transporte/metabolismo , Bactérias Gram-Negativas/enzimologia , Serina Endopeptidases/química , Serina Endopeptidases/metabolismo , Animais , Permeabilidade Capilar , Fator V/metabolismo , Bactérias Gram-Negativas/patogenicidade , Humanos , Mucosa/enzimologia , Mucosa/microbiologia , Serina Endopeptidases/farmacocinética , Serina Endopeptidases/fisiologia , Pele/enzimologia , Pele/microbiologia
17.
Am J Pathol ; 158(2): 581-92, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11159195

RESUMO

The important issue addressed by the studies presented here is the mechanism of neutrophil-mediated damage to endothelial and epithelial cells during inflammation. Binding of neutrophil-released granule proteins to endothelial cells may be involved in vascular damage in patients with inflammatory vascular diseases. We have determined whether granule proteins proteinase 3(PR3) and/or myeloperoxidase (MPO) are internalized into endothelial cells, as examined by UV light, confocal, and electron microscopy. Coincident induction of apoptosis and/or the generation of intracellular oxidants were monitored. The results indicate that human endothelial cells (human umbilical vein endothelial cells, human umbilical arterial endothelial cells, human lung microvascular endothelial cells) internalize both PR3 and MPO, which are detected on the cell surface, in the cytoplasm, and possibly nuclear. Epithelial cells (small airway epithelial cells) internalized MPO but not PR3, implying that the mechanism of PR3 internalization may be cell-type specific and different from that of MPO. Internalization of PR3, but not MPO, correlated with activation of apoptosis. Internalization of MPO correlated with an increase in intracellular oxidant radicals. The requirement for the proteolytic activity of PR3 for the induction of apoptosis was examined by generating PR3-truncated fragments that did not contain the components of the catalytic triad. An apoptotic function was localized to the C-terminal portion of PR3. These studies reveal novel mechanisms by which the neutrophil granule proteins PR3 and MPO contribute to tissue injury at sites of inflammation.


Assuntos
Apoptose , Endotélio Vascular/metabolismo , Oxidantes/metabolismo , Peroxidase/farmacocinética , Serina Endopeptidases/farmacocinética , Transporte Biológico , Células Cultivadas , Endocitose , Endotélio Vascular/citologia , Endotélio Vascular/ultraestrutura , Humanos , Microscopia Eletrônica , Microscopia de Fluorescência , Mieloblastina , Oxirredução , Peroxidase/metabolismo , Estrutura Terciária de Proteína , Serina Endopeptidases/química , Serina Endopeptidases/metabolismo , Fatores de Tempo
18.
FASEB J ; 14(7): 859-70, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10783139

RESUMO

SSCrFCES is a biologically active, recombinant fragment of factor C, which is the endotoxin-sensitive serine protease of the LAL coagulation cascade. The approximately 38 kDa protein represents the LPS binding domain of factor C. A novel secretory signal directs the secretion of SSCrFCES into the culture supernatant of Drosophila cells, and hence it is readily purified. By differential ultrafiltration followed by preparative isoelectric membrane electrophoresis, SSCrFCES was purified as an isoelectrically homogeneous and stable monomeric protein. The ability of SSCrFCES to bind lipid A was analyzed using an ELISA-based assay as well as surface plasmon resonance. SSCrFCES exhibits high positive cooperativity of binding to two or three lipid A molecules, with a Hill's coefficient of 2.2. The 50% endotoxin-neutralizing concentration of SSCrFCES against 200 EU of endotoxin is approximately 0.069 microM, suggesting that SSCrFCES is an effective inhibitor of LAL coagulation cascade. Although partially attenuated by human serum, as little as 1 microM of SSCrFCES inhibits the LPS-induced secretion of hTNF-alpha and hIL-8 by THP-1 and human peripheral blood mononuclear cells with greater potency than polymyxin B. SSCrFCES is noncytotoxic, with a clearance rate of 4.7 ml/min. The L.D.(90) of SSCrFCES for LPS lethality is achieved at 2 microM. These results demonstrate the endotoxin-neutralizing capability of SSCrFCES in vitro and in vivo and its potential use for the treatment of endotoxin-induced septic shock.


Assuntos
Precursores Enzimáticos/farmacologia , Lipopolissacarídeos/metabolismo , Fragmentos de Peptídeos/farmacologia , Serina Endopeptidases/farmacologia , Animais , Proteínas de Artrópodes , Sequência de Bases , Sítios de Ligação , Cromatografia de Afinidade/instrumentação , Primers do DNA , Drosophila , Precursores Enzimáticos/genética , Precursores Enzimáticos/metabolismo , Precursores Enzimáticos/farmacocinética , Caranguejos Ferradura , Humanos , Interleucina-8/antagonistas & inibidores , Interleucina-8/biossíntese , Focalização Isoelétrica , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/toxicidade , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/farmacocinética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/farmacologia , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Serina Endopeptidases/farmacocinética , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossíntese
19.
Clin Exp Allergy ; 28(2): 196-204, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9515593

RESUMO

BACKGROUND: Metachromatic cells obtained from asthmatic subjects demonstrate increased spontaneous and stimulated histamine release in vitro. Their ability to synthesize and store proinflammatory cytokines has focused renewed interest on their role in asthma. OBJECTIVE: The late asthmatic response provides a useful model of clinical asthma. The aim of the study was to examine metachromatic cell derived mediators and histamine releasability in vitro after in vivo allergen exposure in atopic subjects with and without asthma and relate them to the type of physiological response observed. METHODS: Bronchoalveolar lavage (BAL) cells were obtained 4 h after challenge from asthmatics exhibiting a single early response (EAR, n = 5), a dual response (LAR, n = 7), unchallenged (basal, n = 5), atopic non-asthmatic (ANA, n = 6) and non-atopic non-asthmatics (normal, n = 5). BAL histamine and tryptase concentrations and in vitro histamine release (HR) after stimulation with anti-IgE, allergen, A23187, conconavalin A and substance P were compared. RESULTS: Metachromatic cell numbers were lower in normal controls compared with all asthmatic groups and in LAR compared with EAR. Metachromatic cell derived mediators were higher in asthmatic compared with normal subjects. Spontaneous HR in LAR (20.5 +/- 5.0%) was lower than EAR (29.5 +/- 3.9%) and ANA (30.2 +/- 1.4%) (P < 0.05). No differences were seen in stimulated HR between EAR and LAR. HR in ANA stimulated with anti-IgE was greater than LAR (P < 0.05). HR in ANA stimulated with anti-IgE was greater than LAR (P < 0.05). After stimulation with ionophore A23187 (1 microM), release was greater in LAR compared with basal (P < 0.05) and no different at 5 microM. All subject groups responded to substance P (SP) but was significantly more in the asthmatic subjects compared to normal controls (P < 0.05). Allergen challenge did not modify the response of asthmatic subjects to SP. CONCLUSION: Functional differences in metachromatic cell reactivity are present in atopic subjects 4h after in vivo allergen exposure which relate to the physiological response observed after this time and suggest that there is ongoing metachromatic cell degranulation subjects who subsequently develop LAR.


Assuntos
Alérgenos/imunologia , Asma/imunologia , Líquido da Lavagem Broncoalveolar/citologia , Liberação de Histamina/imunologia , Adolescente , Adulto , Alérgenos/farmacologia , Anticorpos Anti-Idiotípicos/farmacologia , Basófilos/citologia , Basófilos/efeitos dos fármacos , Basófilos/metabolismo , Testes de Provocação Brônquica , Quimases , Concanavalina A/farmacologia , Feminino , Humanos , Mediadores da Inflamação/farmacocinética , Contagem de Leucócitos , Masculino , Mastócitos/citologia , Mastócitos/efeitos dos fármacos , Mastócitos/metabolismo , Serina Endopeptidases/farmacocinética , Substância P/farmacologia , Fatores de Tempo , Triptases
20.
Ukr Biokhim Zh (1978) ; 70(6): 35-42, 1998.
Artigo em Russo | MEDLINE | ID: mdl-10402646

RESUMO

Data on study of action plasma inhibitors on activity of pancreatic proteolytic enzymes (trypsin, chymotrypsin) and plant proteinases (papain, bromelain), included in composition of enzyme mixes, used for orally application are submitted. It is established, that serine proteases are more sensitive to inactivation of plasma inhibitors, than cysteine enzymes. Main inhibitor of the papain and bromelain is alpha-2-macroglobulin in complex with which they preserve significant part of initial activity. A high-sensitivity method of determination of activity enzyme combinations, enabling to detect nanograms of them in presence of plasma inhibitors is offered. It can be used for study pharmacokinetic and optimization of enzyme mixes application in clinical practice.


Assuntos
Cisteína Endopeptidases/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Serina Endopeptidases/metabolismo , Inibidores de Serina Proteinase/farmacologia , Animais , Caseínas/metabolismo , Cisteína Endopeptidases/farmacocinética , Inibidores de Cisteína Proteinase/sangue , Humanos , Hidrólise , Serina Endopeptidases/farmacocinética , Inibidores de Serina Proteinase/sangue
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