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1.
J Neurochem ; 150(3): 296-311, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31206169

RESUMEN

Temporal lobe epilepsy (TLE) is a chronic disease, characterized by severe and refractory seizures, triggered in the hippocampus and/or amygdala, disrupting the blood-brain barrier. This disruption can sustain, or aggravate, the epileptic condition. The aim of this study was to evaluate the activation of the kallikrein-kinin system in patients with TLE, as it relates to the maintenance of blood-brain barrier. Human hippocampal sclerotic tissues removed after surgery for seizure control, plasma, and serum were used in the following assays: immunostaining for white blood cells in the TLE hippocampus, C-reactive protein in serum, quantification of plasma kallikrein (PKal) and cathepsin B (CatB) activity in serum and plasma, quantification of C1-inhibitor, analysis of high-molecular-weight kininogen (H-kininogen) fragments, and activation of plasma prekallikrein for comparison with healthy controls. Infiltration of white blood cells in the sclerotic hippocampus and a significant increase in the neutrophil/lymphocyte ratio in the blood of TLE patients were observed. High levels of C-reactive protein (TLE = 1.4 ± 0.3 µg/mL), PKal (TLE = 5.4 ± 0.4 U/mL), and CatB (TLE = 4.9 ± 0.4 U/mL) were also evident in the serum of TLE patients comparing to controls. A strong linear correlation was observed between active CatB and PKal in the serum of TLE patients (r = 0.88). High levels of cleaved H-kininogen and free PKal, and low levels of C1-inhibitor (TLE = 188 ± 12 µg/mL) were observed in the serum of TLE patients. Our data demonstrated that the plasma kallikrein-kinin system is activated in patients with TLE. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.


Asunto(s)
Catepsina B/sangre , Epilepsia del Lóbulo Temporal/metabolismo , Inflamación/metabolismo , Sistema Calicreína-Quinina/fisiología , Calicreínas/sangre , Adulto , Femenino , Hipocampo/metabolismo , Humanos , Masculino , Persona de Mediana Edad
2.
Eur Respir J ; 47(5): 1452-60, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26917604

RESUMEN

Lymphangioleiomyomatosis (LAM) is a cystic lung disease frequently associated with reduced exercise capacity. The aim of this study was to assess safety and efficacy of pulmonary rehabilitation in LAM.This controlled clinical trial included 40 patients with LAM and a low physical activity level. The pulmonary rehabilitation programme comprised 24 aerobic and muscle strength training sessions and education. The primary outcome was exercise capacity (endurance time during a constant work rate exercise test). Secondary outcomes included health-related quality of life (St George's Respiratory Questionnaire (SGRQ)), 6-min walking distance (6MWD), dyspnoea, peak oxygen consumption (V'O2 ), daily physical activity (pedometer), symptoms of anxiety and depression, lung function and peripheral muscle strength (one-repetition maximum).The baseline characteristics were well balanced between the groups. The pulmonary rehabilitation group exhibited improvements in the following outcomes versus controls: endurance time (median (interquartile range) 169 (2-303) s versus -33 (-129-39) s; p=0.001), SGRQ (median (interquartile range) -8 (-16-2) versus 2 (-4-5); p=0.002) and 6MWD (median (interquartile range) 59 (13-81) m versus 20 (-12-30) m; p=0.002). Dyspnoea, peak V'O2 , daily physical activity and muscle strength also improved significantly. No serious adverse events were observed.Pulmonary rehabilitation is a safe intervention and improves exercise capacity, dyspnoea, daily physical activity, quality of life and muscle strength in LAM.


Asunto(s)
Terapia por Ejercicio , Linfangioleiomiomatosis/fisiopatología , Linfangioleiomiomatosis/rehabilitación , Adulto , Ansiedad/diagnóstico , Brasil , Depresión/complicaciones , Depresión/diagnóstico , Disnea/complicaciones , Disnea/diagnóstico , Ejercicio Físico , Prueba de Esfuerzo , Femenino , Humanos , Linfangioleiomiomatosis/psicología , Persona de Mediana Edad , Consumo de Oxígeno , Seguridad del Paciente , Calidad de Vida , Encuestas y Cuestionarios , Resultado del Tratamiento , Caminata
3.
Biochim Biophys Acta ; 1844(3): 545-52, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24373874

RESUMEN

Snake venom metalloproteinases (SVMPs) belonging to P-I class are able to hydrolyze extracellular matrix proteins and coagulation factors triggering local and systemic reactions by multiple molecular mechanisms that are not fully understood. BmooMPα-I, a P-I class SMVP from Bothrops moojeni venom, was active upon neuro- and vaso-active peptides including angiotensin I, bradykinin, neurotensin, oxytocin and substance P. Interestingly, BmooMPα-I showed a strong bias towards hydrolysis after proline residues, which is unusual for most of characterized peptidases. Moreover, the enzyme showed kininogenase activity similar to that observed in plasma and cells by kallikrein. FRET peptide assays indicated a relative promiscuity at its S2-S'2 subsites, with proline determining the scissile bond. This unusual post-proline cleaving activity was confirmed by the efficient hydrolysis of the synthetic combinatorial library MCA-GXXPXXQ-EDDnp, described as resistant for canonical peptidases, only after Pro residues. Structural analysis of the tripeptide LPL complexed with BmooMPα-I, generated by molecular dynamics simulations, assisted in defining the subsites and provided the structural basis for subsite preferences such as the restriction of basic residues at the S2 subsite due to repulsive electrostatic effects and the steric impediment for large aliphatic or aromatic side chains at the S1 subsite. These new functional and structural findings provided a further understanding of the molecular mechanisms governing the physiological effects of this important class of enzymes in envenomation process.


Asunto(s)
Venenos de Crotálidos/enzimología , Calicreínas/metabolismo , Metaloproteasas/metabolismo , Serina Endopeptidasas/metabolismo , Secuencia de Aminoácidos , Animales , Bothrops , Hidrólisis , Cinética , Simulación de Dinámica Molecular , Péptidos/química , Péptidos/metabolismo , Prolil Oligopeptidasas , Radioinmunoensayo , Especificidad por Sustrato
4.
Artículo en Inglés | MEDLINE | ID: mdl-37569034

RESUMEN

Lifestyle and health-related quality of life (HRQoL) are good markers of surgical obesity treatment. This study aimed to investigate the lifestyle and HRQoL of patients at least five years after Roux-en-Y gastric bypass in public (SUS) and private (PVT) Brazilian healthcare systems. In this cross-sectional study, weight loss (WL), % of excess WL (%EWL), diet quality, physical activity, alcohol consumption, and HRQoL were evaluated. Analysis of covariance, binary and multinomial logistic regression, adjusted for confounders, were performed. The SUS group had more vulnerable socioeconomic statuses than the PVT group. Total %WL and % EWL were 24.64 ± 0.99% and 60.46 ± 2.41%, respectively, without difference between groups. In the Pain/Discomfort and Anxiety/Depression domains of HRQoL, more than 50% reported moderate problems without differences between groups. Processed food ingestion was higher in the PVT (132.10 ± 60.15 g/1000 kcal) than in the SUS (103.43 ± 41.72 g/1000 kcal), however, without statistical significance (p = 0.093). The PVT group showed lower physical activity (OR: 0.23; 95%CI: 0.87-0.63; p = 0.004) and a higher risk of alcohol-related problems (OR: 3.23; 95%CI; 1.03-10.10; p = 0.044) compared to SUS group. Participants generally achieved satisfactory WL, regardless of healthcare systems. However, PVT participants had unfavorable lifestyle characteristics, highlighting the need for studies investigating environmental issues post-bariatric surgery.


Asunto(s)
Derivación Gástrica , Obesidad Mórbida , Humanos , Obesidad Mórbida/cirugía , Calidad de Vida , Estudios Transversales , Brasil/epidemiología , Pérdida de Peso , Estilo de Vida , Resultado del Tratamiento , Estudios Retrospectivos
5.
Arch Biochem Biophys ; 498(1): 74-82, 2010 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-20371359

RESUMEN

We report the enzymatic properties and substrate specificity of human recombinant KLK3 in the presence of glycosaminoglycans (GAGs) and sodium citrate. This salt is highly concentrated in prostate and in its presence KLK3 had a similar hydrolytic efficiency as chymotrypsin. In contrast to the latter peptidase, KLK3 activated by sodium citrate efficiently hydrolyzed substrates containing R, H and P at the P1 position. Activated KLK3 also cleaved peptides derived from the bradykinin domain of human kininogen at the same sites as human kallikrein KLK1, but presented low kininogenase activity. Angiotensin I has several sites for hydrolysis by KLK3; however, it was cleaved only at the Y-I bond (DRVY downward arrowIHPFHL). Sodium citrate modulated KLK3 conformation as observed by alterations to the intrinsic fluorescence of phenylalanines and tryptophans. Activated KLK3 was reversibly inhibited by Z-Pro-Prolinal and competitively inhibited by ortho-phenantroline. Together, these are noteworthy observations for the future design of specific non-peptide inhibitors of KLK3 and to find natural substrates.


Asunto(s)
Citratos/farmacología , Glicosaminoglicanos/farmacología , Calicreínas/antagonistas & inhibidores , Calicreínas/metabolismo , Inhibidores de Proteasas/farmacología , Secuencia de Aminoácidos , Angiotensinas/metabolismo , Cloruros/química , Cloruros/farmacología , Activación Enzimática/efectos de los fármacos , Transferencia Resonante de Energía de Fluorescencia , Humanos , Concentración de Iones de Hidrógeno , Hidrólisis , Calicreínas/química , Quininógeno de Bajo Peso Molecular/metabolismo , Datos de Secuencia Molecular , Antígeno Prostático Específico , Sales (Química)/química , Sales (Química)/farmacología , Citrato de Sodio , Especificidad por Sustrato
6.
Obes Surg ; 30(9): 3508-3513, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32314250

RESUMEN

PURPOSE: Pregnant women who have undergone bariatric surgery must be followed to ensure healthy mother-child nutritional status. This study aimed to compare weight status of mother-child dyad after maternal bariatric surgery in public and private Brazilian healthcare system units. MATERIALS AND METHODS: This retrospective matched case-control included 19 women who underwent Roux-en-Y gastric bypass surgery performed by the same private clinical surgical team and 19 age- and preoperative body mass index (BMI) matched patients from a public hospital. All 38 female patients reported a postoperative spontaneous pregnancy. The T test of independent samples and Pearson chi-square test were used to investigate inter-group differences. RESULTS: Patients in the private system were more frequently married (94.7% versus 68.4%, p = 0.036) and had a higher educational level (94.7% versus 36.8%, p = 0.01 for tertiary education) but lower BMI, compared with those in the public system (pre-gestational = 25.7 ± 3.2 versus 28.5 ± 5.0 kg/m2, p = 0.049; post-gestational = 24.6 ± 1.6 versus 29.0 ± 6.0 kg/m2, p = 0.040). The interval from bariatric surgery to conception was shorter among public system patients (21.1 ± 13.9 versus 43.4 ± 31.2 months, p = 0.009). In both groups, almost 90% of children were born at full term and with adequate weights. CONCLUSION: Despite differences in the characteristics of public and private systems, the mother-child dyads in both groups achieved satisfactory post-bariatric surgery gestation outcomes. The type of medical system does not appear to influence pregnancy outcomes or neonatal weight status conditions.


Asunto(s)
Cirugía Bariátrica , Derivación Gástrica , Obesidad Mórbida , Brasil , Niño , Femenino , Humanos , Madres , Obesidad Mórbida/cirugía , Embarazo , Estudios Retrospectivos
7.
Orphanet J Rare Dis ; 12(1): 74, 2017 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-28427470

RESUMEN

BACKGROUND: Lymphangioleiomyomatosis (LAM) is included within group 5 of the current PH classification (unclear multifactorial mechanisms). However, data regarding the occurrence of PH in LAM are scarce. The aims of the study were to describe the prevalence and characteristics of PH in a large cohort of LAM patients with different levels of severity, and to evaluate the role of echocardiography and carbon monoxide diffusion capacity (DLCO) as screening methods for PH in LAM. METHODS: One hundred five LAM patients underwent transthoracic echocardiography, pulmonary function tests (PFTs) and 6-min walk test (6MWT). Patients with a suspicion of PH on echocardiography, defined by the presence of estimated systolic pulmonary artery pressure (PAP) over 35 mmHg or PFT showing DLco below 40% of the predicted value, underwent right heart catheterisation to confirm the diagnosis of PH. RESULTS: Eight patients (7.6%) had PH confirmed on right heart catheterisation, six patients (5.7%) had a pre-capillary pattern and two patients (1.9%) had a post-capillary profile. Only one patient (1%) had mean PAP over 35 mmHg. Patients with PH had lower FEV1 and DLCO in PFTs and greater oxygen desaturation and dyspnea intensity during 6MWT compared with those without PH. In 63% of the patients with confirmed PH, the right heart catheterisation was performed based only on DLCO result. CONCLUSIONS: The prevalence of PH is low in LAM patients. Pulmonary hypertension in LAM is typically mild and significantly associated with pulmonary parenchymal involvement. Carbon monoxide diffusion capacity significantly improved the identification of PH in LAM patients.


Asunto(s)
Monóxido de Carbono/metabolismo , Hipertensión Pulmonar/diagnóstico , Hipertensión Pulmonar/epidemiología , Linfangioleiomiomatosis/diagnóstico , Linfangioleiomiomatosis/epidemiología , Adulto , Ecocardiografía , Femenino , Humanos , Hipertensión Pulmonar/metabolismo , Hipertensión Pulmonar/patología , Linfangioleiomiomatosis/metabolismo , Linfangioleiomiomatosis/patología , Masculino , Persona de Mediana Edad , Prevalencia , Pruebas de Función Respiratoria
8.
Peptides ; 27(12): 3363-9, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17030465

RESUMEN

The kallikrein-kinin system is involved in a variety of physiological and pathological processes. Components of this system, identified in rat and human brains, can be altered in neurodegenerative processes such as Alzheimer's disease. Here, we studied kinin release and its inactivation in rats submitted to chronic cerebroventricular infusion of beta-amyloid (Abeta) peptide. Neurodegeneration was confirmed by histological analysis of brain samples. In cerebrospinal fluid of animals infused with Abeta, bradykinin concentration was increased, as determined by radioimmunoassay. However, in the brain of Abeta group, we only detected the tripeptide Arg-Pro-Pro, purified by reversed-phase chromatography and characterized by liquid chromatography-electrospray ionization mass spectrometry. This fragment of bradykinin indicated the possible participation of kinin-processing enzymes in the brain such as a prolyl oligopeptidase.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Bradiquinina/antagonistas & inhibidores , Bradiquinina/metabolismo , Encéfalo/metabolismo , Animales , Modelos Animales de Enfermedad , Ratas
9.
Vet Parasitol ; 219: 44-52, 2016 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-26921038

RESUMEN

Rhipicephalus microplus is an ectoparasite responsible for transmissions of babesiosis and anaplasmosis causing large losses to livestock production. To survive R. microplus tick produces several active molecules, such as protease inhibitors. This ectoparasite has been described as a rich source of serine protease inhibitors most of them are Kunitz-BPTI members named BmTIs which have no clear function yet. In the present work, we described the expression and functional characterization of rBmTI-A which showed to be similar to the native BmTI-A, a double-headed Kunitz-BPTI inhibitor, capable to inhibit trypsin, human neutrophil elastase (HNE), human plasma kalikrein (HuPK) and human plasmin. rBmTI-A was able to cause a decrease of HUVEC cell viability. Besides, the rBmTI-A showed to be a potent inhibitor of "in vitro" vessel formation. Our results suggested that BmTI-A may participate in the blood acquisition process interfering in the vessel formation during the tick parasite life stage, around 20 days. In conclusion, BmTI-A is a promising molecule to be used in the drug design and development of new method of R. microplus control.


Asunto(s)
Neovascularización Fisiológica/efectos de los fármacos , Rhipicephalus/genética , Rhipicephalus/metabolismo , Inhibidores de Serina Proteinasa , Secuencia de Aminoácidos , Animales , Supervivencia Celular/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Enzimas/metabolismo , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Orden Génico , Células Endoteliales de la Vena Umbilical Humana , Humanos , Cinética , Datos de Secuencia Molecular , Alineación de Secuencia , Inhibidores de Serina Proteinasa/genética , Inhibidores de Serina Proteinasa/metabolismo , Inhibidores de Serina Proteinasa/farmacología , Transcriptoma
10.
PLoS One ; 10(3): e0121721, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25822177

RESUMEN

Human H-kininogen (120 kDa) plays a role in many pathophysiological processes and interacts with the cell surface through protein receptors and proteoglycans, which mediate H-kininogen endocytosis. In the present work we demonstrate that H-kininogen containing bradykinin domain is internalized and different endogenous kininogenases are present in CHO-K1 cells. We used CHO-K1 (wild type) and CHO-745 (mutant deficient in proteoglycans biosynthesis) cell lines. H-kininogen endocytosis was studied using confocal microscopy, and its hydrolysis by cell lysate fraction was determined by immunoblotting. Bradykinin release was also measured by radioimmunoassay. H-kininogen interaction with the cell surface of CHO-745 cells resulted in bradykinin release by serine proteases. In CHO-K1 cells, which produce heparan and chondroitin sulfate proteoglycans, internalization of H-kininogen through its bradykinin domain can occur on lipid raft domains/caveolae. Nevertheless bradykinin-free H-kininogen was not internalized by CHO-K1 cells. The H-kininogen present in acidic endosomal vesicles in CHO-K1 was approximately 10-fold higher than the levels in CHO-745. CHO-K1 lysate fractions were assayed at pH 5.5 and intact H-kininogen was totally hydrolyzed into a 62 kDa fragment. By contrast, at an assay pH 7.4, the remained fragments were 115 kDa, 83 kDa, 62 kDa and 48 kDa in size. The antipain-Sepharose chromatography separated endogenous kininogenases from CHO-K1 lysate fraction. No difference was detected in the assays at pH 5.5 or 7.4, but the proteins in the fraction bound to the resin released bradykinin from H-kininogen. However, the proteins in the unbound fraction cleaved intact H-kininogen at other sites but did not release bradykinin. H-kininogen can interact with extravascular cells, and is internalized dependent on its bradykinin domain and cell surface proteoglycans. After internalization, H-kininogen is proteolytically processed by intracellular kininogenases. The present data also demonstrates that serine or cysteine proteases in lipid raft domains/caveolae on the CHO cell can hydrolyze H-kininogen, thus releasing kinins.


Asunto(s)
Bradiquinina/metabolismo , Endocitosis/fisiología , Quininógeno de Alto Peso Molecular/metabolismo , Animales , Células CHO , Caveolas/metabolismo , Línea Celular , Cricetulus , Endosomas/metabolismo , Hidrólisis , Calicreínas/metabolismo , Proteoglicanos/metabolismo , Serina Proteasas/metabolismo
11.
Int Immunopharmacol ; 4(10-11): 1401-8, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15313437

RESUMEN

The carrageenan model of pleurisy is described as temporal plasma exudation (1-5 h) with extensive neutrophil infiltration and release of proteinases into the pleural cavity. The aim of this work was to study the effects of serine proteinase inhibitors on the inflammatory process induced by administration of carrageenan to the rat pleural cavity and on release of kinins in pleural exudate. Pleurisy was induced by injecting carrageenan and serine proteinase inhibitors simultaneously into the pleural cavity. The proteinase inhibitors used were: aprotinin, a plasma kallikrein inhibitor; recombinant leech derived tryptase inhibitor-2PL (LDTI-2PL), a plasmin inhibitor; Boophilus microplus trypsin inhibitors (BmTIs); trypsin; plasma kallikrein; plasmin and neutrophil elastase inhibitors; and a synthetic neutrophil elastase inhibitor (EIsynt). Administration of carrageenan with LDTI-2PL and BmTIs induced a marked increase in exudation (143% and 201%) and leukocyte migration (288% and 408%), respectively, when compared to the control group. Pleural exudate from LDTI-2PL and BmTIs plus carrageenan-treated rats showed a significant increase in plasma kallikrein-like activity, measured by chromogenic substrate hydrolysis. The specific inhibition of enzymatic activity with aprotinin confirmed that 50% of S2302 hydrolysis was produced by plasma kallikrein-like enzymes. Kinin release was increased by 97% and 103% in exudates from LDTI-2PL and BmTIs plus carrageenan-treated rats, respectively. Considering that the plasmin inhibitors LDTI-2PL and BmTIs increased exudation, leukocyte migration and bradykinin release, our results suggest an anti-inflammatory role for plasmin in the pleurisy model.


Asunto(s)
Bradiquinina/metabolismo , Pleuresia/metabolismo , Inhibidores de Serina Proteinasa/farmacología , Animales , Carragenina , Quimiotaxis de Leucocito/efectos de los fármacos , Exudados y Transudados/metabolismo , Fibrinolisina/antagonistas & inhibidores , Fibrinolisina/metabolismo , Ixodidae , Sanguijuelas , Masculino , Pleuresia/inducido químicamente , Radioinmunoensayo , Ratas , Ratas Wistar
12.
Int Immunopharmacol ; 2(13-14): 1861-5, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12489800

RESUMEN

Human plasma kallikrein (huPK) is a serine proteinase involved in many biological processes including those of the kallikrein-kinin system. The action of huPK on kininogen results in bradykinin (BK) release, a potent mediator of inflammatory responses. BK generation may be influenced by several agents, and the aim of this work was to investigate the effect of glycosaminoglycans (GAGs) on human high-molecular-weight kininogen (HK) hydrolysis by huPK and on inflammation. huPK was pre-incubated in the absence and presence of different GAGs, followed by the addition of kininogen. Bradykinin released at different times was measured by radioimmunoassay, and KM and kcat were calculated. Tuna and bovine dermatan sulfates, the most potent GAGs studied, reduced by 80% and 68%, respectively, the catalytic efficiency of huPK (control = 4. x 10(4) M(-1) s(-1) in BK release. The effect of bovine dermatan sulfate (BDS) on inflammatory response was studied in rat paw edema induced by carrageenin and hourly determined (1-4 h) by plethysmography. BDS significantly reduced the inflammatory response in the first and second hours of measurements (24% and 28%, respectively), p < 0.05. GAGs were shown to reduce bradykinin release "in vitro" and in an inflammation model. This reduction may play a role in the control or maintenance of some pathological and physiological processes.


Asunto(s)
Dermatán Sulfato/uso terapéutico , Edema/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Calicreína Plasmática/química , Animales , Bradiquinina/metabolismo , Carragenina , Dermatán Sulfato/farmacología , Edema/inducido químicamente , Edema/metabolismo , Humanos , Hidrólisis , Inflamación/inducido químicamente , Inflamación/metabolismo , Mediadores de Inflamación/metabolismo , Cinética , Quininógeno de Alto Peso Molecular/química , Quininógeno de Alto Peso Molecular/metabolismo , Masculino , Calicreína Plasmática/metabolismo , Ratas , Ratas Wistar
13.
Mol Biochem Parasitol ; 187(2): 111-6, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23354130

RESUMEN

We studied the substrate specificity requirements of recombinant cysteine peptidases from Plasmodium falciparum, falcipain-2 (FP-2) and falcipain-3 (FP-3), using fluorescence resonance energy transfer (FRET) peptides as substrates. Systematic modifications were introduced in the lead sequence Abz-KLRSSKQ-EDDnp (Abz=ortho-aminobenzoic acid; EDDnp=N-[2,4-dinitrophenyl]ethylenediamine) resulting in five series assayed to map S3-S'2 subsite specificity. Despite high sequence identity and structural similarity between FP-2 and FP-3, noteworthy differences in substrate specificity were observed. The S1 subsite of FP-2 preferentially accommodates peptides containing the positively charged residue Arg in P1, while FP-3 has a clear preference for the hydrophobic residue Leu in this position. The S2 subsite of FP-2 and FP-3 presents a strict specificity for hydrophobic residues, with Leu being the residue preferred by both enzymes. FP-2 did not show preference for the residues present at P3, while FP-3 hydrolysed the peptide Abz-ALRSSRQ-EDDnp, containing Ala at P3, with the highest catalytic efficiency of all series studied. FP-2 has high susceptibility for substrates containing hydrophobic residues in P'1, while FP-3 accommodates well peptides containing Arg in this position. The S'2 subsite of both enzymes demonstrated broad specificity. In addition, radioimmunoassay experiments indicated that kinins can be generated by FP-2 and FP-3 proteolysis of high molecular weight kininogen (HK). Both enzymes excised Met-Lys-bradykinin, Lys-bradykinin and bradykinin from the fluorogenic peptide Abz-MISLMKRPPGFSPFRSSRI-NH2, which corresponds to the Met(375) to Ile(393) sequence of HK. The capability of FP-2 and FP-3 to release kinins suggests the involvement of these enzymes in the modulation of malaria pathophysiology.


Asunto(s)
Cisteína Endopeptidasas/metabolismo , Calicreínas/metabolismo , Plasmodium falciparum/enzimología , Quininógenos/metabolismo , Cininas/metabolismo , Especificidad por Sustrato
14.
Arch Oral Biol ; 57(5): 469-76, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22041019

RESUMEN

OBJECTIVE: In this study we investigated the possible use of human demineralised dentine matrix (DHDM), obtained from the extracted teeth, as bone graft material and evaluated the expression of vascular endothelial growth factor (VEGF) induced by this material in the healing process of tooth sockets of rats. DESIGN: To evaluate bone regeneration and expression of VEGF induced by DHDM, thirty-two male Wistar rats weighing approximately 200 g were used. After maxillary second molar extraction, the left sockets were filled with DHDM and the right sockets were naturally filled by blood clot (control). The animals were sacrificed at 3, 7, 14 and 21 days after surgery and upper maxillaries were processed for histological, morphometric and immunohistochemical analyses. DHDM was used to evaluate the mechanical effect of bone graft material into sockets. Expression of VEGF was determined by immunohistochemistry in all groups. RESULTS: Our results demonstrated a significant increase in the newly formed bone tissue in sockets of 7, 14 and 21 days and a significant increase in VEGF expression at days 7 and 14 on treated sockets. CONCLUSIONS: Our results showed that DHDM increases the expression of VEGF and accelerates the healing process in rats tooth sockets, by stimulating bone deposition and also vessels formation. These results suggest that DHDM has osteoinductive/osteoconductive potential and may represent an efficient grafting material on guided bone regeneration.


Asunto(s)
Regeneración Ósea/efectos de los fármacos , Dentina , Alveolo Dental/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Cicatrización de Heridas/efectos de los fármacos , Análisis de Varianza , Animales , Biomarcadores/metabolismo , Humanos , Inmunohistoquímica , Masculino , Maxilar/cirugía , Ratas , Ratas Wistar , Estadísticas no Paramétricas , Extracción Dental
15.
Biochimie ; 93(3): 618-23, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21167902

RESUMEN

Saliva of blood-sucking arthropods contains a complex mixture of anti-haemostatic, anti-inflammatory and immune-modulator compounds. Among anti-haemostatic factors, there are anticoagulants, vasodilators and platelet aggregation inhibitors. Previous analyses of the sialotranscriptome of Aedes aegypti showed the potential presence of a Kazal-type serine protease inhibitor in the female salivary glands, carcass and also in the whole male, which inhibitor we named AaTI (A. aegypti thrombin inhibitor). Recently, we expressed and characterized rAaTI as a trypsin inhibitor, and its anticoagulant activity [1]. In this work we characterized the thrombin inhibition mechanism of rAaTI. Recombinant AaTI was able to prolong prothrombin time, activated partial thromboplastin time and thrombin time. In contrast, AaTIΔ (rAaTI truncated form) and C-terminal AaTI acidic tail prolong only thrombin time. In the competition assay, rAaTI, AaTIΔ or C-terminal AaTI acidic tail-thrombin interactions seem to be affected by heparin but not by hirudin, suggesting that rAaTI binds to thrombin exosite 2. Finally, the thrombin inhibition assay of rAaTI showed an uncompetitive inhibition mechanism. In conclusion, rAaTI can probably inhibit thrombin by interacting with thrombin exosite 2, and the interaction is not mediated by the AaTI C-terminal region, since the truncated AaTIΔ form also prolongs thrombin time.


Asunto(s)
Aedes , Antitrombinas/farmacología , Proteínas de Insectos/farmacología , Trombina/antagonistas & inhibidores , Inhibidor de Tripsina Pancreática de Kazal/química , Secuencia de Aminoácidos , Animales , Antitrombinas/química , Antitrombinas/aislamiento & purificación , Coagulación Sanguínea/efectos de los fármacos , Femenino , Proteínas de Insectos/química , Proteínas de Insectos/aislamiento & purificación , Masculino , Datos de Secuencia Molecular
16.
Biochimie ; 93(10): 1701-9, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21689719

RESUMEN

KLK13 is a kallikrein-related peptidase preferentially expressed in tonsils, esophagus, testis, salivary glands and cervix. We report the activation of KLK13 by kosmotropic salts and glycosaminoglycans and its substrate specificity by employing a series of five substrates derived from the fluorescence resonance energy transfer (FRET) peptide Abz-KLRSSKQ-EDDnp. KLK13 hydrolyzed all these peptides only at basic residues with highest efficiency for R; furthermore, the S(3) to S(2)' subsites accepted most of the natural amino acids with preference also for basic residues. Using a support-bound FRET peptide library eight peptide substrates were identified containing sequences of proteins found in testis and one with myelin basic protein sequence, each of which was well hydrolyzed by KLK13. Histatins are salivary peptides present in higher primates with broad antifungal and mucosal healing activities that are generated from the hydrolysis from large precursor peptides. KLK13 efficiently hydrolyzed synthetic histatin 3 exclusively at R(25) (DSHAKRHHGYKRKFHEKHHSHRGYR(25)↓SNYLYDN) that is the first cleavage observed inside the salivary gland. In conclusion, the observed hydrolytic activities of KLK13 and its co-localization with its activators, glycosaminoglycans in the salivary gland and high concentration of sodium citrate in male reproductive tissues, indicates that KLK13 may play a role in the defense of the upper digestive apparatus and in male reproductive organs.


Asunto(s)
Glicosaminoglicanos/farmacología , Calicreínas/metabolismo , Sales (Química)/farmacología , Citratos/farmacología , Activación Enzimática/efectos de los fármacos , Femenino , Humanos , Masculino , Glándulas Salivales/metabolismo , Citrato de Sodio , Especificidad por Sustrato
17.
Biochimie ; 93(10): 1839-45, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21784122

RESUMEN

In the plasma kallikrein-kinin system, it has been shown that when plasma prekallikrein (PK) and high molecular weight kininogen (HK) assemble on endothelial cells, plasma kallikrein (huPK) becomes available to cleave HK, releasing bradykinin, a potent mediator of the inflammatory response. Because the formation of soluble glycosaminoglycans occurs concomitantly during the inflammatory processes, the effect of these polysaccharides on the interaction of HK on the cell surface or extracellular matrix (ECM) of two endothelial cell lines (ECV304 and RAEC) was investigated. In the presence of Zn(+2), HK binding to the surface or ECM of RAEC was abolished by heparin; reduced by heparan sulfate, keratan sulfate, chondroitin 4-sulfate or dermatan sulfate; and not affected by chondroitin 6-sulfate. By contrast, only heparin reduced HK binding to the ECV304 cell surface or ECM. Using heparin-correlated molecules such as low molecular weight dextran sulfate, low molecular weight heparin and N-desulfated heparin, we suggest that these effects were mainly dependent on the charge density and on the N-sulfated glucosamine present in heparin. Surprisingly, PK binding to cell- or ECM-bound-HK and PK activation was not modified by heparin. However, the hydrolysis of HK by huPK, releasing BK in the fluid phase, was augmented by this glycosaminoglycan in the presence of Zn(2+). Thus, a functional dichotomy exists in which soluble glycosaminoglycans may possibly either increase or decrease the formation of BK. In conclusion, glycosaminoglycans that accumulated in inflammatory fluids or used as a therapeutic drug (e.g., heparin) could act as pro- or anti-inflammatory mediators depending on different factors within the cell environment.


Asunto(s)
Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Heparina/farmacología , Precalicreína/metabolismo , Biotinilación/efectos de los fármacos , Línea Celular , Matriz Extracelular/metabolismo , Glicosaminoglicanos/farmacología , Humanos , Quininógenos , Unión Proteica/efectos de los fármacos
18.
Pulmäo RJ ; 22(2): 35-39, 2013.
Artículo en Portugués | LILACS | ID: lil-704347

RESUMEN

A DPOC cursa com múltiplas comorbidades. A depressão, juntamente com a ansiedade, é uma das associações mais comuns e, provavelmente, a menos diagnosticada e tratada no contexto da DPOC. As implicações da falta de diagnóstico e de tratamento adequado da depressão vão desde uma menor aderência ao tratamento da DPOC e pior qualidade de vida até o aumento no número de consultas, admissões hospitalares, exacerbações e óbitos. A necessidade de investigação de depressão em todos os pacientes portadores de DPOC já é um consenso, e existem vários questionários validados para tal. Poucos estudos prospectivos avaliaram o manejo da depressão nessa situação; entretanto, as evidências atuais sugerem um benefício da terapia com medicamentos antidepressivos, terapia cognitivo--comportamental e, em especial, dos programas de reabilitação. Há uma carência de estudos, em especial de ensaios clínicos randomizados, para definir o real impacto da depressão na DPOC, bem como os benefícios de sua detecção precoce e definição da melhor abordagem terapêutica nesses pacientes. Entretanto, os trabalhos existentes têm demonstrado a importância do diagnóstico e a eficácia do tratamento da depressão nos pacientes portadores de DPOC. Os médicos responsáveis pelo tratamento desses pacientes não podem continuar negligenciando essa associação


There are multiple comorbidities associated with COPD. Depression and anxiety are some of the most common such co-morbidities and are probably underdiagnosed and undertreated in COPD patients. The implications of depression going undiagnosed and untreated include low adherence to COPD treatment and a poorer quality of life, as well as an increase inthe number of physician consultations, hospital admissions, exacerbations, and deaths.There is a consensus that patients with COPD should be screened for depression, and a number of questionnaires have beenvalidated for that purpose. Although there have been few prospective studies evaluating the management of depression in COPD patients, current evidence suggests that there arebenefits provided by treatment with antidepressants, cognitivebehavioral therapy and, in particular, rehabilitation programs.There is lack of studies, especially randomized clinical trials, evaluating the true impact of depression in COPD patients, as well as the benefits of early detection, and defining the best therapeutic approach in such patients. However, there have been studies demonstrating the importance of diagnosing depression in COPD patients and the effectiveness of treating depression in such patients. Physicians responsible for treatingpatients with COPD cannot continue to neglect this association


Asunto(s)
Humanos , Depresión/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Rehabilitación
19.
Biol Chem ; 388(11): 1183-94, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17976011

RESUMEN

The complete amino acid sequence obtained by electrospray ionization tandem mass spectrometry of the proteinase inhibitor CmPI-II isolated from Cenchritis muricatus is described. CmPI-II is a 5480-Da protein with three disulfide bridges that inhibits human neutrophil elastase (HNE) (K(i) 2.6+/-0.2 nM), trypsin (K(i) 1.1+/-0.9 nM), and other serine proteinases such as subtilisin A (K(i) 30.8+/-1.2 nM) and pancreatic elastase (K(i) 145.0+/-4.4 nM); chymotrypsin, pancreatic and plasma kallikreins, thrombin and papain are not inhibited. CmPI-II shares homology with the Kazal-type domain and may define a new group of 'non-classical' Kazal inhibitors according to its Cys(I)-Cys(V) disulfide bridge position. The 3D model of CmPI-II exhibits similar secondary structure characteristics to Kazal-type inhibitors and concurs with circular dichroism experiments. A 3D model of the CmPI-II/HNE complex provides a structural framework for the interpretation of its experimentally determined K(i) value. The model shows both similar and different contacts at the primary binding sites in comparison with the structure of turkey ovomucoid third domain (OMTKY3)/HNE used as template. Additional contacts calculated at the protease-inhibitor interface could also contribute to the association energy of the complex. This inhibitor represents an exception in terms of specificity owing to its ability to strongly inhibit elastases and trypsin.


Asunto(s)
Modelos Moleculares , Inhibidor de Tripsina Pancreática de Kazal/química , Secuencia de Aminoácidos , Animales , Dicroismo Circular , Electroforesis en Gel de Poliacrilamida , Humanos , Elastasa de Leucocito/antagonistas & inhibidores , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Caracoles , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Ultravioleta , Espectrometría de Masas en Tándem , Inhibidor de Tripsina Pancreática de Kazal/aislamiento & purificación , Inhibidor de Tripsina Pancreática de Kazal/farmacología
20.
Artículo en Inglés | MEDLINE | ID: mdl-16546427

RESUMEN

Human neutrophil elastase inhibition was detected in a crude extract of the marine snail Cenchritis muricatus (Gastropoda, Mollusca). This inhibitory activity remained after heating this extract at 60 degrees C for 30 min. From this extract, three human neutrophil elastase inhibitors (designated CmPI-I, CmPI-II and CmPI-III) were purified by affinity and reversed-phase chromatographies. Homogeneity of CmPI-I and CmPI-II was confirmed, while CmPI-III showed a single peak in reversed-phase chromatography, but heterogeneity in SDS-PAGE with preliminary molecular masses in the range of 18.4 to 22.0 kDa. In contrast, MALDI-TOF mass spectrometry of CmPI-I and CmPI-II showed that these inhibitors are molecules of low molecular mass, 5576 and 5469 Da, respectively. N-terminal amino acid sequences of CmPI-I (6 amino acids) and CmPI-II (20 amino acids) were determined. Homology to Kazal-type protease inhibitors was preliminarily detected for CmPI-II. Both inhibitors, CmPI-I and CmPI-II are able to inhibit human neutrophil elastase strongly, with equilibrium dissociation constant (Ki) values of 54.2 and 1.6 nM, respectively. In addition, trypsin and pancreatic elastase were also inhibited, but not plasma kallikrein or thrombin. CmPI-I and CmPI-II are the first human neutrophil elastase inhibitors described in a mollusk.


Asunto(s)
Elastasa de Leucocito/antagonistas & inhibidores , Inhibidores de Serina Proteinasa/aislamiento & purificación , Inhibidores de Serina Proteinasa/farmacología , Caracoles/química , Secuencia de Aminoácidos , Animales , Electroforesis en Gel de Poliacrilamida , Humanos , Datos de Secuencia Molecular , Océanos y Mares , Elastasa Pancreática/antagonistas & inhibidores , Calicreína Plasmática/antagonistas & inhibidores , Homología de Secuencia de Aminoácido , Inhibidores de Serina Proteinasa/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Trombina/antagonistas & inhibidores , Inhibidores de Tripsina/farmacología
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