38 results on '"Magalhães GS"'
Search Results
2. Correction: Factors associated with arterial stiffness assessed by pulse pressure amplification in healthy children and adolescents: a cross-sectional study.
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Salomão LP, Magalhães GS, da Silva JFP, Dos Santos LM, Moura ICG, Rezende BA, and Rodrigues-Machado MG
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- 2023
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3. Factors associated with arterial stiffness assessed by pulse pressure amplification in healthy children and adolescents: a cross-sectional study.
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Salomão LP, Magalhães GS, da Silva JFP, Dos Santos LM, Gomes Moura IC, Rezende BA, and Rodrigues-Machado MG
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- Humans, Male, Child, Adolescent, Female, Young Adult, Adult, Blood Pressure, Cross-Sectional Studies, Hemodynamics, Heart Rate, Vascular Stiffness
- Abstract
Background: Increasing evidence suggests that reducing pulse pressure amplification (PPA) plays an important role in pathogenesis and progression of cardiovascular disease. This is a cross-sectional, observational, and analytical study in which we evaluated the associated factors with a greater chance of reducing PPA in 136 healthy children and adolescents aged 8 to 19 years old stratified by gender and age group., Methods: Arterial stiffness and vascular and hemodynamic parameters were non-invasively measured using Mobil-O-Graph® (IEM, Stolberg, Germany), a cuff-based oscillometric device. PPA was expressed as the peripheral-to-central pulse pressure ratio (PPp / PPc). Participants with PPA < 1.49 were considered as part of the arterial stiffness group., Results: In a univariate model, the increase in total vascular resistance, the reflection coefficient and the augmentation pressure were more likely to have arterial stiffness in all groups. The factors most likely to have arterial stiffness (as assessed by the reduction of the PPA) in the multivariate model were increasing age, the reflection coefficient and cardiac index in the total sample, male group and child and adolescent groups. In addition to age in the female group, cardiac output, stroke volume, and AIx@75 were the factors most likely to present arterial stiffness., Conclusions: The results show for the first time in children and adolescents that the factors most likely to reduce PPA are related to the reflection wave, which determines aortic pressures and, therefore, left ventricular afterload., (© 2023. The Author(s).)
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- 2023
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4. Synthesis of Human Bone Morphogenetic Protein-2 (hBMP-2) in E. coli Periplasmic Space: Its Characterization and Preclinical Testing.
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Oliveira JE, Suzuki MF, Damiani R, Lima ER, Amaral KC, Santos AMS, Magalhães GS, Faverani LP, Pereira LAVD, and Bartolini P
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- Animals, Biological Assay, Bioreactors, Cell Line, Chromatography, Gel, Chromatography, High Pressure Liquid, Chromatography, Reverse-Phase, Fermentation, Humans, Male, Mice, Osteogenesis, Rats, Wistar, Skull pathology, Rats, Bone Morphogenetic Protein 2 biosynthesis, Escherichia coli metabolism, Periplasm metabolism
- Abstract
Human BMP-2, a homodimeric protein that belongs to the TGF- β family, is a recognized osteoinductor due to its capacity of inducing bone regeneration and ectopic bone formation. The administration of its recombinant form is an alternative to autologous bone grafting. A variety of E. coli- derived hBMP-2 has been synthesized through refolding of cytoplasmic inclusion bodies. The present work reports the synthesis, purification, and characterization of periplasmic hBMP-2, obtained directly in its correctly folded and authentic form, i.e., without the initial methionine typical of the cytoplasmic product that can induce undesired immunoreactivity. A bacterial expression vector was constructed including the DsbA signal peptide and the cDNA of hBMP-2. The periplasmic fluid was extracted by osmotic shock and analyzed via SDS-PAGE, Western blotting, and reversed-phase high-performance liquid chromatography (RP-HPLC). The purification was carried out by heparin affinity chromatography, followed by high-performance size-exclusion chromatography (HPSEC). HPSEC was used for qualitative and quantitative analysis of the final product, which showed >95% purity. The classical in vitro bioassay based on the induction of alkaline phosphatase activity in myoblastic murine C2C12 cells and the in vivo bioassay consisting of treating calvarial critical-size defects in rats confirmed its bioactivity, which matched the analogous literature data for hBMP-2.
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- 2021
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5. Recombinant Production and Characterization of a New Toxin from Cryptops iheringi Centipede Venom Revealed by Proteome and Transcriptome Analysis.
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De Lucca Caetano LH, Nishiyama-Jr MY, de Carvalho Lins Fernandes Távora B, de Oliveira UC, de Loiola Meirelles Junqueira-de-Azevedo I, Faquim-Mauro EL, and Magalhães GS
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- Animals, Chilopoda genetics, Edema chemically induced, Gene Expression Profiling, Immune Sera, Male, Mice, Inbred BALB C, Proteome, Rabbits, Recombinant Proteins, Mice, Arthropod Venoms chemistry, Arthropod Venoms toxicity, Chilopoda chemistry
- Abstract
Among the Chilopoda class of centipede, the Cryptops genus is one of the most associated with envenomation in humans in the metropolitan region of the state of São Paulo. To date, there is no study in the literature about the toxins present in its venom. Thus, in this work, a transcriptomic characterization of the Cryptops iheringi venom gland, as well as a proteomic analysis of its venom, were performed to obtain a toxin profile of this species. These methods indicated that 57.9% of the sequences showed to be putative toxins unknown in public databases; among them, we pointed out a novel putative toxin named Cryptoxin-1. The recombinant form of this new toxin was able to promote edema in mice footpads with massive neutrophils infiltration, linking this toxin to envenomation symptoms observed in accidents with humans. Our findings may elucidate the role of this toxin in the venom, as well as the possibility to explore other proteins found in this work.
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- 2021
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6. Influence of the expression vector and its elements on recombinant human prolactin synthesis in Escherichia coli; co-directional orientation of replication and transcription is highly critical.
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Affonso R, Suzuki MF, Magalhães GS, and Bartolini P
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- Cloning, Molecular, Escherichia coli metabolism, Gene Expression Regulation, Bacterial, Humans, Protein Biosynthesis, Escherichia coli genetics, Prolactin biosynthesis, Prolactin genetics, Recombinant Proteins
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The aim of the present work was to define a bacterial expression system that is particularly efficient for the synthesis of recombinant human prolactin (hPRL). In previous work, based on experiments that were basically carried out in parallel with the present ones, the synthesis of rec-hPRL by the p1813-hPRL vector in E. coli HB2151 was >500 mg/L, while it was much lower here (2.5-4-fold), in the RB791 and RRI strains. The highest positive influence on rec-hPRL synthesis was due to the transcription-replication co-orientation of hPRL cDNA and the ori/antibiotic resistance gene, responsible for up to a ~ 5-6-fold higher expression yield. In conclusion, this work confirmed that each bacterial strain of E. coli has a genetic background that can allow a different level of heterologous protein synthesis. The individual study of each element indicated that its action critically depends on the reading orientation in which it is located inside the vector: co-directional orientation of replication and transcription, in fact, greatly increased the level of rec-hPRL expression., (Copyright © 2021 Elsevier B.V. All rights reserved.)
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- 2021
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7. Asthma: role of the angiotensin-(1-7)/Mas (MAS1) pathway in pathophysiology and therapy.
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Gregório JF, Rodrigues-Machado MDG, Santos RAS, Carvalho-Ribeiro IA, Nunes OM, Oliveira IFA, Vasconcellos AVO, Campagnole-Santos MJ, and Magalhães GS
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- Angiotensin I, Humans, Peptide Fragments, Proto-Oncogene Proteins, Receptors, G-Protein-Coupled, Asthma drug therapy, Quality of Life
- Abstract
The incidence of asthma is a global health problem and requires studies aimed for the development of new treatments to improve its clinical management, reducing personal and economic burdens on the health system. Therefore, the discovery of mediators that promote anti-inflammatory and pro-resolutive effects are highly desirable to improve lung function and quality of life of asthmatic patients. In that regard, experimental studies have shown that the angiotensin-(1-7)/Mas receptor (MAS1) of the renin-angiotensin system is a potential candidate for the treatment of asthma. Therefore, we have reviewed findings related to the function of the angiotensin-(1-7)/Mas pathway in regulating the processes associated with inflammation, including leukocyte influx, fibrogenesis, pulmonary dysfunction and the resolution of inflammation in asthma. Thus, a knowledge of the role of the angiotensin-(1-7)/Mas can help pave the way for the development of new treatments for this disease, which has high morbidity and mortality, through new types of experiments and clinical trials., (© 2021 The British Pharmacological Society.)
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- 2021
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8. Angiotensin-(1-7)/Mas receptor modulates anti-inflammatory effects of exercise training in a model of chronic allergic lung inflammation.
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Gregório JF, Magalhães GS, Rodrigues-Machado MG, Gonzaga KER, Motta-Santos D, Cassini-Vieira P, Barcelos LS, Vieira MAR, Santos RAS, and Campagnole-Santos MJ
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- Angiotensin I blood, Animals, Asthma blood, Asthma metabolism, Disease Models, Animal, Exercise Therapy, Male, Mice, Inbred BALB C, Peptide Fragments blood, Pneumonia blood, Pneumonia metabolism, Mice, Angiotensin I metabolism, Asthma therapy, Peptide Fragments metabolism, Pneumonia therapy
- Abstract
Aims: Exercise training increases circulating and tissue levels of angiotensin-(1-7) [Ang-(1-7)], which was shown to attenuate inflammation and fibrosis in different diseases. Here, we evaluated whether Ang-(1-7)/Mas receptor is involved in the beneficial effects of aerobic training in a chronic model of asthma., Material and Methods: BALB/c mice were subjected to a protocol of asthma induced by ovalbumin sensitization (OVA; 4 i.p. injections) and OVA challenge (3 times/week for 4 weeks). Simultaneously to the challenge period, part of the animals was continuously treated with Mas receptor antagonist (A779, 1 μg/h; for 28 days) and trained in a treadmill (TRE; 60% of the maximal capacity, 1 h/day, 5 days/week during 4 weeks). PGC1-α mRNA expression (qRT-PCR), plasma IgE and lung cytokines (ELISA), inflammatory cells infiltration (enzymatic activity assay) and airway remodeling (by histology) were evaluated., Key Findings: Blocking the Mas receptor with A779 increased IgE and IL-13 levels and prevented the reduction in extracellular matrix deposition in airways in OVA-TRE mice. Mas receptor blockade prevented the reduction of myeloperoxidase activity, as well as, prevented exercise-induced IL-10 increase. These data show that activation of Ang-(1-7)/Mas receptor pathway is involved in the anti-inflammatory and anti-fibrotic effects of aerobic training in an experimental model of chronic asthma., Significance: Our results support exercise training as a non-pharmacological tool to defeat lung remodeling induced by chronic pulmonary inflammation. Further, our result also supports development of new therapy based on Ang-(1-7) or Mas agonists as important tool for asthma treatment in those patients that cannot perform aerobic training., (Copyright © 2021 Elsevier Inc. All rights reserved.)
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- 2021
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9. Oral Formulation of Angiotensin-(1-7) Promotes Therapeutic Actions in a Model of Eosinophilic and Neutrophilic Asthma.
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Magalhães GS, Gregório JF, Cançado Ribeiro ATP, Baroni IF, Vasconcellos AVO, Nakashima GP, Oliveira IFA, de Matos NA, Castro TF, Bezerra FS, Sinisterra RD, Pinho V, Teixeira MM, Santos RAS, Rodrigues-Machado MG, and Campagnole-Santos MJ
- Abstract
The presence of eosinophils and neutrophils in the lungs of asthmatic patients is associated with the severity of the disease and resistance to corticosteroids. Thus, defective resolution of eosinophilic and neutrophilic inflammation is importantly related to exacerbation of asthma. In this study, we investigated a therapeutic action of angiotensin-(1-7) (Ang-(1-7)) in a model of asthma induced by ovalbumin (OVA) and lipopolysaccharide (LPS). Balb-c mice were sensitized and challenged with OVA. Twenty-three hours after the last OVA challenge, experimental groups received LPS, and 1 h and 7 h later, mice were treated with oral formulation of Ang-(1-7). On the next day, 45 h after the last challenge with OVA, mice were subjected to a test of motor and exploratory behavior; 3 h later, lung function was evaluated, and bronchoalveolar lavage fluid (BALF) and lungs were collected. Motor and exploratory activities were lower in OVA + LPS-challenged mice. Treatment with Ang-(1-7) improved these behaviors, normalized lung function, and reduced eosinophil, neutrophil, myeloperoxidase (MPO), eosinophilic peroxidase (EPO), and ERK1/2 phosphorylation (p-ERK1/2) in the lungs. In addition, Ang-(1-7) decreased the deposition of mucus and extracellular matrix in the airways. These results extended those of previous studies by demonstrating that oral administration of Ang-(1-7) at the peak of pulmonary inflammation can be valuable for the treatment of neutrophil- and eosinophil-mediated asthma. Therefore, these findings potentially provide a new drug to reverse the natural history of the disease, unlike the current standards of care that manage the disease symptoms at best., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Magalhães, Gregório, Cançado Ribeiro, Baroni, Vasconcellos, Nakashima, Oliveira, Matos, Castro, Bezerra, Sinisterra, Pinho, Teixeira, Santos, Rodrigues-Machado and Campagnole-Santos.)
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- 2021
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10. Predictors and reference equations for augmentation index, an arterial stiffness marker, in healthy children and adolescents.
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Santos LMD, Gomes IC, Pinho JF, Neves-Alves CM, Magalhães GS, Campagnole-Santos MJ, and da Glória Rodrigues-Machado M
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- Adolescent, Adult, Blood Pressure, Child, Cross-Sectional Studies, Female, Humans, Male, Pulse Wave Analysis, Quality of Life, Risk Factors, Young Adult, Vascular Stiffness
- Abstract
Objectives: To investigate predictors and propose reference equations for the augmentation index normalized to 75 bpm heart rate (AIx@75) in healthy children and adolescents., Methods: This was a cross-sectional, observational study involving 134 healthy children and adolescents aged 9 to 19 years old. Participants were categorized into child (n=53) and adolescent (n=81) groups, as well as into male (n=69) and female (n=65) groups. We evaluated AIx@75, vascular and hemodynamic parameters, anthropometric data, physical activity profile, and quality of life (Peds-QL4.0; physical, emotional, social and school domains)., Results: The predictors of AIx@75 in the whole sample were age, peripheral diastolic blood pressure (pDBP), mean arterial pressure, pulse pressure amplification (PPA), systolic volume (SV), cardiac index (CI), and pulse wave velocity (PWV; R2=80.47%). In the male group, the predictors of AIx@75 were SV, CI, total vascular resistence (TVR), and PWV (R2=78.56%), while in the female group, they were pDBP, PPA, SV, and PWV (R2=82.45%). In the children, they were pDBP, PPA, SV, and PWV (R2=79.17%), while in the adolescents, they were body mass index, pDBP, PPA, SV, TVR, and PWV (R2=81.57%)., Conclusion: In the present study, we used a representative sample from Belo Horizonte to establish normality values of AIx@75. We also identified, for the first time, independent predictors of AIx@75 in healthy children and adolescents categorized by sex and age. Determining AIx@75 reference equations may facilitate the early diagnosis of preclinical atherosclerosis and allow an objective measure of the vascular effects of therapeutic interventions aimed at modifying cardiovascular risk factors.
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- 2021
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11. Treatment with inhaled formulation of angiotensin-(1-7) reverses inflammation and pulmonary remodeling in a model of chronic asthma.
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Magalhães GS, Gregório JF, Ramos KE, Cançado-Ribeiro ATP, Baroni IF, Barcelos LS, Pinho V, Teixeira MM, Santos RAS, Rodrigues-Machado MG, and Campagnole-Santos MJ
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- Administration, Inhalation, Airway Remodeling immunology, Animals, Asthma diagnosis, Asthma etiology, Biomarkers, Cytokines, Disease Models, Animal, Immunoglobulin E blood, Immunoglobulin E immunology, Lung drug effects, Lung immunology, Lung pathology, Matrix Metalloproteinases metabolism, Mice, Ovalbumin adverse effects, Airway Remodeling drug effects, Angiotensin I administration & dosage, Asthma drug therapy, Asthma metabolism, Peptide Fragments administration & dosage, Vasodilator Agents administration & dosage
- Abstract
Asthma is characterized by inflammation, pulmonary remodeling and bronchial hyperresponsiveness. We have previously shown that treatment with angiotensin-(1-7) [Ang-(1-7)] promotes resolution of eosinophilic inflammation and prevents chronic allergic lung inflammation. Here, we evaluated the effect of treatment with the inclusion compound of Ang-(1-7) in hydroxypropyl β-cyclodextrin (HPβCD) given by inhalation on pulmonary remodeling in an ovalbumin (OVA)-induced chronic allergic lung inflammation. Mice were sensitized to ovalbumin (OVA; 4 injections over 42 days, 14 days apart) and were challenged 3 times per week, for 4 weeks (days 21-46). After the 2nd week of challenge, mice were treated with Ang-(1-7) by inhalation (4.5 μg of Ang-(1-7) included in 6.9 μg of HPβCD for 14 days, i.e. days 35-48). Mice were killed 72 h after the last challenge and blood, bronchoalveolar lavage fluid (BALF) and lungs were collected. Histology and morphometric analysis were performed in the lung. Metalloproteinase (MMP)-9 and MMP-12 expression and activity, IL-5, CCL11 in the lung and plasma IgE were measured. After 2 weeks of OVA challenge there was an increase in plasma IgE and in inflammatory cells infiltration in the lung of asthmatic mice. Treatment with inhaled administration of Ang-(1-7)/HPβCD for 14 days reduced eosinophils, IL5, CCL11 in the lung and plasma IgE. Treatment of asthmatic mice with Ang-(1-7)/HPβCD by inhalation reversed pulmonary remodeling by reducing collagen deposition and MMP-9 and MMP-12 expression and activity. These results show for the first time that treatment by inhalation with Ang-(1-7) can reverse an installed asthma, inhibiting pulmonary inflammation and remodeling., Competing Interests: Declaration of Competing Interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Elsevier GmbH. All rights reserved.)
- Published
- 2020
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12. Oral formulation angiotensin-(1-7) therapy attenuates pulmonary and systemic damage in mice with emphysema induced by elastase.
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Bastos AC, Magalhães GS, Gregório JF, Matos NA, Motta-Santos D, Bezerra FS, Santos RAS, Campagnole Santos MJ, and Rodrigues-Machado MG
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- Administration, Oral, Animals, Disease Models, Animal, Homeostasis drug effects, Interleukin-1beta metabolism, Locomotion drug effects, Lung metabolism, Male, Mice, Mice, Inbred C57BL, Pulmonary Alveoli drug effects, Pulmonary Alveoli metabolism, Pulmonary Emphysema metabolism, Swine, Angiotensin I pharmacology, Lung drug effects, Pancreatic Elastase pharmacology, Peptide Fragments pharmacology, Pulmonary Emphysema drug therapy
- Abstract
Angiotensin-(1-7) [Ang-(1-7)], a peptide of the renin-angiotensin system, has anti-inflammatory, anti-fibrotic and antiproliferative effects in acute or chronic inflammatory disease of respiratory system. In this study, we evaluated the effect of treatment with Ang-(1-7) on pulmonary tissue damage and behavior of mice submitted to experimental model of elastase-induced pulmonary emphysema (PE). Initially, male C57BL/6 mice were randomly assigned into two main groups: control (CTRL) and PE. In the PE group, the animals received three intratracheal instillations of pancreatic porcine elastase (PPE) at 1-week intervals (0.2 IU in 50 μL of saline). The CTRL group received the same volume of saline solution (50 μL). Twenty-four hours after the last instillation, animals of the PE group were randomly divided into two groups: PE and PE + Ang-(1-7). The PE + Ang-(1-7) group was treated with 60 μg/kg of Ang-(1-7) and 92 μg kg of HPβCD in gavage distilled water, 100 μl. The CTRL and PE groups were treated with vehicle (HPβCD- 92 μg/kg in distilled water per gavage, 100 μl), orally daily for 3 weeks. On the 19th day of treatment, all groups were tested in relation to locomotor activity and exploratory behavior. After 48 h, the animals were euthanized and lungs were collected. The animals of PE group presented rupture of alveolar walls and consequently reduction of alveolar tissue area. Treatment with Ang-(1-7) partially restored the alveolar tissue area. The PE reduced the locomotor activity and the exploratory behavior of the mice in relation to the control group. Treatment with Ang-(1-7) attenuated this change. In addition, it was observed that Ang-(1-7) reduced lung levels of IL-1β and increased levels of IL-10. These results show an anti-inflammatory effect of Ang-(1-7), inducing the return of pulmonary homeostasis and attenuation of the behavioral changes in experimental model of PE by elastase., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2019 Elsevier GmbH. All rights reserved.)
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- 2020
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13. Human bone morphogenetic protein-2 (hBMP-2) characterization by physical-chemical, immunological and biological assays.
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Suzuki MF, Oliveira JE, Damiani R, Lima ER, Amaral KC, Santos AMS, Magalhães GS, Faverani LP, Pereira LAVD, Silva FM, and Bartolini P
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Commercially available preparations of methionyl-human BMP-2 and CHO-derived hBMP-2, which belongs to the transforming growth factor β (TGF-β) superfamily, were used for a complete characterization. This protein is an extremely efficient osteoinductor that plays an important role during bone regeneration and embryonic development. Characterization was carried out via SDS-PAGE and Western blotting, followed by reversed-phase HPLC, size-exclusion HPLC and MALDI-TOF-MS. The classical in vitro bioassay, based on the induction of alkaline phosphatase activity in C2C12 cells, confirmed that hBMP-2 biological activity is mostly related to the dimeric form, being ~ 4-fold higher for the CHO-derived glycosylated form when compared with the E. coli counterpart. The E. coli-derived met-hBMP-2 has shown, by MALDI-TOF-MS, a large presence of the bioactive dimer. A more complex molecular mass (MM) distribution was found for the CHO-derived product, whose exact MM has never been reported because of its variable glycosylation. A method based on RP-HPLC was set up, allowing a quantitative and qualitative hBMP-2 determination even directly on ongoing culture media. Considering that hBMP-2 is highly unstable, presenting moreover an extremely high aggregate value, we believe that these data pave the way to a necessary characterization of this important factor when synthesized by DNA recombinant techniques in different types of hosts.
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- 2020
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14. When spider and snake get along: Fusion of a snake disintegrin with a spider phospholipase D to explore their synergistic effects on a tumor cell.
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Siqueira RAGB, Calabria PAL, Caporrino MC, Tavora BCLF, Barbaro KC, Faquim-Mauro EL, Della-Casa MS, and Magalhães GS
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- Animals, Humans, Melanoma, Experimental, Mice, Platelet Aggregation drug effects, Recombinant Fusion Proteins chemistry, Spiders, Viperidae, Disintegrins genetics, Phospholipase D genetics, Recombinant Fusion Proteins pharmacology
- Abstract
Venoms of spiders and snakes contain toxins extremely active and, thus, provide a natural source for the development of new biotechnological tools. Among the diversity of toxins present in the venom of spiders from genus Loxosceles, the phospholipases D (PLDs) show high hydrolytic activity upon lysophosphatidylcholine (LPC) and sphingomyelin (SM), generating bioactive phospholipids such as cyclic phosphatidic acid (cPA). Since this mediator has been shown to play a major role in complex signaling pathways, including inhibition of tumor cells, the PLDs may hold the key to learn how toxins could be used for therapeutic purposes. However, the strong platelet aggregation of PLDs and their lack of selectivity impose a major limitation. On the other hand, disintegrins present in the venoms of Viperidae snakes are a potent inhibitor of platelet aggregation and possess high affinity and specificity to molecules called integrins that are highly expressed in some tumor cells, such as murine melanoma B16F10. Therefore, disintegrins might be suitable molecules to carry the PLDs to the malignant cells, so both toxins may work synergistically to eliminate these cells. Thus, in this work, a recombinant PLD from Loxosceles gaucho spider was recombinantly fused to a disintegrin from Echis carinatus snake to form a hybrid toxin called Rechistatin. This recombinant toxin was successfully expressed in bacteria, showed binding activity in B16F10 murine melanoma cells and exerted a synergistic cytotoxicity effect on these cells. Therefore, the approach presented in this work may represent a new strategy to explore new potential applications for spider PLDs., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2019
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15. Changes in aortic pulse wave components, pulse pressure amplification, and hemodynamic parameters of children and adolescents with type 1 diabetes.
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Duarte SV, de Souza Rajão J, Pinho JF, Dos Santos LM, Alves-Neves CM, Magalhães GS, Ribeiro-Oliveira A Jr, and Rodrigues-Machado MDG
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- Adolescent, Case-Control Studies, Child, Cross-Sectional Studies, Female, Humans, Male, Vascular Stiffness physiology, Aorta physiology, Blood Pressure physiology, Diabetes Mellitus, Type 1 physiopathology, Hemodynamics physiology, Pulse Wave Analysis
- Abstract
Background/objective: Type 1 diabetes mellitus (DM1) presents important risk factors for cardiovascular events., Objective: To compare the components of the aortic pulse wave (APW) and the hemodynamic parameters among children and adolescents with DM1 and healthy individuals., Methods: This is a cross-sectional study, with 36 children and adolescents diagnosed with DM1 (11.9 ± 3.2 years) matched by sex and age with the control group (n = 36, 12.4 ± 2.9 years). The components of the APW and the hemodynamic parameters were evaluated non-invasively, using Mobil-O-Graph., Results: On the week of the evaluation, DM1 patients presented glycated hemoglobin (hemoglobin A1C [HbA1c]) of 9.48 ± 2.22% and fasting glycemia of 222.58 ± 93.22 mg/dL. Augmentation index (AIx@75), reflection coefficient, and augmentation pressure (AP) were significantly higher in the DM1 group (29.0 ± 9.7%, 63.0 ± 7.9, and 7.8 ± 2.7 mm Hg, respectively) compared with the control group (20.6 ± 7.9%, 53.4 ± 9.1 and 4.9 ± 2.1 mm Hg, respectively). The systolic volume (52.6 ± 11.9 and 60 ± 12.4 mL) and the cardiac output (4.3 ± 0.5 and 4.6 ± 0.5 L/min) decreased in the DM1 group in relation to the control group. The pulse pressure amplification (PPA) was significantly lower in the DM1 group (1.4 ± 0.15) compared with the control group (1.6 ± 0.17). PPA correlated negatively with total vascular resistance (TVR), AP and reflection coefficient, and positively with cardiac index in both groups. In the DMI group, the AIx@75 correlated negatively with age, height, systolic volume, and PPA, and correlated positively with the TVR and reflection coefficient., Conclusions: These results confirm the presence of arterial stiffness in this population and extend the knowledge, showing, for the first time, the reduction of PPA in the DM1 group., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2019
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16. Echocardiographic Assessment of Ventricular Function in Young Patients with Asthma.
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De-Paula CR, Magalhães GS, Jentzsch NS, Botelho CF, Mota CCC, Murça TM, Ramalho LFC, Tan TC, Capuruço CAB, and Rodrigues-Machado MDG
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- Adolescent, Case-Control Studies, Child, Diastole physiology, Echocardiography, Doppler, Pulsed methods, Exercise Test methods, Female, Humans, Male, Quality of Life, Reference Values, Respiratory Function Tests methods, Severity of Illness Index, Statistics, Nonparametric, Surveys and Questionnaires, Systole physiology, Time Factors, Ventricular Dysfunction diagnostic imaging, Ventricular Dysfunction physiopathology, Asthma physiopathology, Exercise physiology, Exercise Tolerance physiology, Ventricular Function physiology
- Abstract
Background: Despite significant advances in understanding the pathophysiology and management of asthma, some of systemic effects of asthma are still not well defined., Objectives: To compare heart function, baseline physical activity level, and functional exercise capacity in young patients with mild-to-moderate asthma and healthy controls., Methods: Eighteen healthy (12.67 ± 0.39 years) and 20 asthmatics (12.0 ± 0.38 years) patients were enrolled in the study. Echocardiography parameters were evaluated using conventional and tissue Doppler imaging (TDI)., Results: Although pulmonary acceleration time (PAT) and pulmonary artery systolic pressure (PASP) were within normal limits, these parameters differed significantly between the control and asthmatic groups. PAT was lower (p < 0.0001) and PASP (p < 0.0002) was higher in the asthma group (114.3 ± 3.70 ms and 25.40 ± 0.54 mmHg) than the control group (135.30 ± 2.28 ms and 22.22 ± 0.40 mmHg). The asthmatic group had significantly lower early diastolic myocardial velocity (E', p = 0.0047) and lower E' to late (E'/A', p = 0.0017) (13.75 ± 0.53 cm/s and 1.70 ± 0.09, respectively) compared with control group (15.71 ± 0.34 cm/s and 2.12 ± 0.08, respectively) at tricuspid valve. In the lateral mitral valve tissue Doppler, the asthmatic group had lower E' compared with control group (p = 0.0466; 13.27 ± 0.43 cm/s and 14.32 ± 0.25 cm/s, respectively), but there was no statistic difference in the E'/A' ratio (p = 0.1161). Right isovolumetric relaxation time was higher (p = 0.0007) in asthmatic (57.15 ± 0.97 ms) than the control group (52.28 ± 0.87 ms), reflecting global myocardial dysfunction. The right and left myocardial performance indexes were significantly higher in the asthmatic (0.43 ± 0.01 and 0.37 ± 0.01, respectively) compared with control group (0.40 ± 0.01 and 0.34 ± 0.01, respectively) (p = 0.0383 and p = 0.0059, respectively). Physical activity level, and distance travelled on the six-minute walk test were similar in both groups., Conclusion: Changes in echocardiographic parameters, evaluated by conventional and TDI, were observed in mild-to-moderate asthma patients even with normal functional exercise capacity and baseline physical activity level. Our results suggest that the echocardiogram may be useful for the early detection and evoluation of asthma-induced cardiac changes.
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- 2018
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17. Toxin Fused with SUMO Tag: A New Expression Vector Strategy to Obtain Recombinant Venom Toxins with Easy Tag Removal inside the Bacteria.
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Shimokawa-Falcão LH, Caporrino MC, Barbaro KC, Della-Casa MS, and Magalhães GS
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- Animals, Arthropod Proteins genetics, Arthropod Proteins toxicity, Blood Platelets drug effects, Bothrops, Crotalid Venoms genetics, Crotalid Venoms toxicity, Cysteine Endopeptidases metabolism, Disintegrins genetics, Disintegrins toxicity, Escherichia coli genetics, Humans, Phospholipase D genetics, Phospholipase D toxicity, Platelet Aggregation drug effects, Platelet Aggregation Inhibitors toxicity, Recombinant Fusion Proteins toxicity, SUMO-1 Protein metabolism, Spider Venoms, Spiders, Cysteine Endopeptidases genetics, SUMO-1 Protein genetics
- Abstract
Many animal toxins may target the same molecules that need to be controlled in certain pathologies; therefore, some toxins have led to the formulation of drugs that are presently used, and many other drugs are still under development. Nevertheless, collecting sufficient toxins from the original source might be a limiting factor in studying their biological activities. Thus, molecular biology techniques have been applied in order to obtain large amounts of recombinant toxins into Escherichia coli . However, most animal toxins are difficult to express in this system, which results in insoluble, misfolded, or unstable proteins. To solve these issues, toxins have been fused with tags that may improve protein expression, solubility, and stability. Among these tags, the SUMO (small ubiquitin-related modifier) has been shown to be very efficient and can be removed by the Ulp1 protease. However, removing SUMO is a labor- and time-consuming process. To enhance this system, here we show the construction of a bicistronic vector that allows the expression of any protein fused to both the SUMO and Ulp1 protease. In this way, after expression, Ulp1 is able to cleave SUMO and leave the protein interest-free and ready for purification. This strategy was validated through the expression of a new phospholipase D from the spider Loxosceles gaucho and a disintegrin from the Bothrops insularis snake. Both recombinant toxins showed good yield and preserved biological activities, indicating that the bicistronic vector may be a viable method to produce proteins that are difficult to express.
- Published
- 2017
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18. Chronic allergic pulmonary inflammation is aggravated in angiotensin-(1-7) Mas receptor knockout mice.
- Author
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Magalhães GS, Rodrigues-Machado MG, Motta-Santos D, Alenina N, Bader M, Santos RA, Barcelos LS, and Campagnole-Santos MJ
- Subjects
- Animals, Bronchoalveolar Lavage Fluid, Cytokines metabolism, Extracellular Signal-Regulated MAP Kinases metabolism, Hypersensitivity physiopathology, Lung metabolism, Lung pathology, Lung physiopathology, Mice, Knockout, Physical Conditioning, Animal, Pneumonia physiopathology, Proto-Oncogene Mas, Swimming, Angiotensin I metabolism, Hypersensitivity complications, Hypersensitivity metabolism, Peptide Fragments metabolism, Pneumonia complications, Pneumonia metabolism, Proto-Oncogene Proteins metabolism, Receptors, G-Protein-Coupled metabolism
- Abstract
The angiotensin-(1-7) [ANG-(1-7)]/Mas receptor pathway is currently recognized as a counterbalancing mechanism of the renin-angiotensin system in different pathophysiological conditions. We have previously described that treatment with ANG-(1-7) attenuates lung inflammation and remodeling in an experimental model of asthma. In the present study, we investigated whether lack of the Mas receptor could alter the inflammatory response in a model of chronic allergic lung inflammation induced by ovalbumin (OVA). Mas receptor wild-type (MasWT) and knockout (MasKO) mice were subjected to four doses of OVA (20 μg/mice ip) with a 14-day interval. At the 21st day, nebulization with OVA (1%) was started, three times per week until the 46th day. Control groups received saline (0.9% ip) and were nebulized with saline (0.9%). MasWT-OVA developed a modest inflammatory response and minor pulmonary remodeling to OVA challenge. Strikingly, MasKO-OVA presented a significant increase in inflammatory cell infiltrate, increase in extracellular matrix deposition, increase in thickening of the alveolar parenchyma, increase in thickening of the smooth muscle layer of the pulmonary arterioles, increase in proinflammatory cytokine and chemokine levels in the lungs, characteristic of chronic asthma. Additionally, MasKO-OVA presented an increase in ERK1/2 phosphorylation compared with MasWT-OVA. Furthermore, MasKO-OVA showed a worse performance in a test of maximum physical exercise compared with MasWT-OVA. Our study shows that effects triggered by the Mas receptor are important to attenuate the inflammatory and remodeling processes in a model of allergic lung inflammation in mice. Our data indicate that impairment of the ANG-(1-7)/Mas receptor pathway may lead to worsening of the pathophysiological changes of asthma., (Copyright © 2016 the American Physiological Society.)
- Published
- 2016
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19. Characterization of Neuwiedin, a new disintegrin from Bothrops neuwiedi venom gland with distinct cysteine pattern.
- Author
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Lima-Dos-Santos I, Della-Casa MS, Portes-Junior JA, Calabria PA, Magalhães GS, and Moura-da-Silva AM
- Subjects
- Amino Acid Sequence, Animals, Cell Adhesion drug effects, Cloning, Molecular, Endothelial Cells drug effects, Escherichia coli genetics, Molecular Sequence Data, Platelet Aggregation drug effects, Recombinant Proteins chemistry, Sequence Alignment, Sequence Analysis, DNA, Bothrops, Crotalid Venoms chemistry, Cysteine chemistry, Disintegrins chemistry, Salivary Glands metabolism
- Abstract
Disintegrins are cysteine-rich toxins containing the RGD motif exposed in a loop that binds integrins such as αIIbβ3, α5β1 and αvβ3. The flexibility of the RGD loop, controlled by the profile of the cysteine pairs and the residues flanking the RGD sequence, are key structural features for the functional activity of these molecules. Recently, our group reported a transcript in the venom gland of Bothrops neuwiedi corresponding to a new P-II SVMP precursor, BnMPIIx, in which the RGD-binding loop includes many substituted residues and unique cysteine residues at the C-terminal. In this paper, we obtained the recombinant disintegrin domain of BnMPIIx, Neuwiedin, which inhibited ADP-induced platelet aggregation, endothelial cell adhesion to fibrinogen and tube formation in Matrigel with no particular selectivity to αIIbβ3 or endothelial cell integrins. This value was also comparable to the inhibition observed with other recombinant disintegrins with conserved cysteine positions and residues in RGD loop. In this regard, Neuwiedin is an important component to understand the functional relevance of the diversity generated by accelerated evolution of venom toxins as well as to find out eventual new disintegrin-dependent targets that may be approached with disintegrins., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
- Published
- 2015
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20. Angiotensin-(1-7) attenuates airway remodelling and hyperresponsiveness in a model of chronic allergic lung inflammation.
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Magalhães GS, Rodrigues-Machado MG, Motta-Santos D, Silva AR, Caliari MV, Prata LO, Abreu SC, Rocco PR, Barcelos LS, Santos RA, and Campagnole-Santos MJ
- Subjects
- Animals, Bronchial Hyperreactivity chemically induced, Bronchial Hyperreactivity metabolism, Bronchial Hyperreactivity physiopathology, Collagen metabolism, Cytokines metabolism, Disease Models, Animal, Hypertrophy, Right Ventricular chemically induced, Hypertrophy, Right Ventricular physiopathology, Hypertrophy, Right Ventricular prevention & control, Immunoglobulin E blood, Inflammation Mediators metabolism, Lung metabolism, Lung physiopathology, Male, Mice, Inbred BALB C, Mitogen-Activated Protein Kinase 1 metabolism, Mitogen-Activated Protein Kinase 3 metabolism, Ovalbumin, Phosphorylation, Pneumonia chemically induced, Pneumonia metabolism, Pneumonia physiopathology, Proto-Oncogene Mas, Proto-Oncogene Proteins agonists, Proto-Oncogene Proteins metabolism, Receptors, G-Protein-Coupled agonists, Receptors, G-Protein-Coupled metabolism, Respiratory Hypersensitivity chemically induced, Respiratory Hypersensitivity metabolism, Respiratory Hypersensitivity physiopathology, Signal Transduction drug effects, Airway Remodeling drug effects, Angiotensin I pharmacology, Anti-Inflammatory Agents pharmacology, Bronchial Hyperreactivity prevention & control, Bronchoconstriction drug effects, Lung drug effects, Peptide Fragments pharmacology, Pneumonia prevention & control, Respiratory Hypersensitivity prevention & control
- Abstract
Background and Purpose: A long-term imbalance between pro- and anti-inflammatory mediators leads to airway remodelling, which is strongly correlated to most of the symptoms, severity and progression of chronic lung inflammation. The Angiotensin-(1-7) [Ang-(1-7)]/Mas receptor axis of the renin-angiotensin system is associated with attenuation of acute and chronic inflammatory processes. In this study, we investigated the effects of Ang-(1-7) treatment in a model of chronic allergic lung inflammation., Experimental Approach: Mice were sensitized to ovalbumin (OVA; 4 injections over 42 days, 14 days apart) and were challenged three times per week (days 21-46). These mice received Ang-(1-7) (1 μg·h(-1) , s.c.) by osmotic mini-pumps, for the last 28 days. Histology and morphometric analysis were performed in left lung and right ventricle. Airway responsiveness to methacholine, analysis of Ang-(1-7) levels (RIA), collagen I and III (qRT-PCR), ERK1/2 and JNK (Western blotting), IgE (elisa), cytokines and chemokines (elisa multiplex), and immunohistochemistry for Mas receptors were performed., Key Results: Infusion of Ang-(1-7) in OVA-sensitized and challenged mice decreased inflammatory cell infiltration and collagen deposition in the airways and lung parenchyma, and prevented bronchial hyperresponsiveness. These effects were accompanied by decreased IgE and ERK1/2 phosphorylation, and decreased pro-inflammatory cytokines. Mas receptors were detected in the epithelium and bronchial smooth muscle, suggesting a site in the lung for the beneficial actions of Ang-(1-7)., Conclusions and Implications: Ang-(1-7) exerted beneficial attenuation of three major features of chronic asthma: lung inflammation, airway remodelling and hyperresponsiveness. Our results support an important protective role of Ang-(1-7) in lung inflammation., (© 2015 The British Pharmacological Society.)
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- 2015
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21. Crystallization and preliminary X-ray diffraction analysis of a novel sphingomyelinase D from Loxosceles gaucho venom.
- Author
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Ullah A, Magalhães GS, Masood R, Mariutti RB, Coronado MA, Murakami MT, Barbaro KC, and Arni RK
- Subjects
- Amino Acid Sequence, Crystallization, Crystallography, X-Ray, Molecular Sequence Data, Arthropod Proteins chemistry, Phosphoric Diester Hydrolases chemistry, Spider Venoms enzymology
- Abstract
Brown spider envenomation results in dermonecrosis, intravascular coagulation, haemolysis and renal failure, mainly owing to the action of sphingomyelinases D (SMases D), which catalyze the hydrolysis of sphingomyelin to produce ceramide 1-phosphate and choline or the hydrolysis of lysophosphatidylcholine to produce lysophosphatidic acid. Here, the heterologous expression, purification, crystallization and preliminary X-ray diffraction analysis of LgRec1, a novel SMase D from Loxosceles gaucho venom, are reported. The crystals belonged to space group P21212, with unit-cell parameters a = 52.98, b = 62.27, c = 84.84 Å and diffracted to a maximum resolution of 2.6 Å.
- Published
- 2014
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22. A neutralizing recombinant single chain antibody, scFv, against BaP1, A P-I hemorrhagic metalloproteinase from Bothrops asper snake venom.
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Castro JM, Oliveira TS, Silveira CR, Caporrino MC, Rodriguez D, Moura-da-Silva AM, Ramos OH, Rucavado A, Gutiérrez JM, Magalhães GS, Faquim-Mauro EL, and Fernandes I
- Subjects
- Amino Acid Sequence, Animals, Antibody Specificity, Antivenins chemistry, Escherichia coli metabolism, Female, Immunoglobulin Fragments pharmacology, Inflammation chemically induced, Inflammation prevention & control, Mice, Mice, Inbred BALB C, Molecular Sequence Data, Neutralization Tests, Recombinant Proteins chemistry, Recombinant Proteins pharmacology, Tumor Suppressor Proteins chemistry, Tumor Suppressor Proteins immunology, Ubiquitin Thiolesterase chemistry, Ubiquitin Thiolesterase immunology, Antivenins pharmacology, Bothrops metabolism, Hemorrhage chemically induced, Metalloproteases antagonists & inhibitors, Metalloproteases toxicity, Snake Venoms antagonists & inhibitors, Tumor Suppressor Proteins antagonists & inhibitors, Ubiquitin Thiolesterase antagonists & inhibitors
- Abstract
BaP1 is a P-I class snake venom metalloproteinase (SVMP) relevant in the local tissue damage associated with envenomings by Bothrops asper, a medically important snake species in Central America and parts of South and North America. The main treatment for these accidents is the passive immunotherapy using antibodies raised in horses. In order to obtain more specific and batch-to-batch consistent antivenons, recombinant antibodies are considered a good option compared to animal immunization. We constructed a recombinant single chain variable fragment (scFv) from a monoclonal antibody against BaP1 (MABaP1) formerly secreted by a hybridoma clone. This recombinant antibody was cloned into pMST3 vector in fusion with SUMO protein and contains VH and VL domains linked by a flexible (G4S)3 polypeptide (scFvBaP1). The aim of this work was to produce scFvBaP1 and to evaluate its potential concerning the neutralization of biologically important activities of BaP1. The cytoplasmic expression of this construct was successfully achieved in C43 (DE3) bacteria. Our results showed that scFvBaP1-SUMO fusion protein presented an electrophoretic band of around 43 kDa from which SUMO alone corresponded to 13.6 kDa, and only the scFv was able to recognize BaP1 as well as the whole venom by ELISA. In contrast, neither an irrelevant scFv anti-LDL nor its MoAb partner recognized it. BaP1-induced fibrinolysis was significantly neutralized by scFvBaP1, but not by SUMO, in a concentration-dependent manner. In addition, scFvBaP1, as well as MaBaP1, completely neutralized in vivo hemorrhage, muscle necrosis, and inflammation induced by the toxin. Docking analyses revealed possible modes of interaction of the recombinant antibody with BaP1. Our data showed that scFv recognized BaP1 and whole B. asper venom, and neutralized biological effects of this SVMP. This scFv antibody can be used for understanding the molecular mechanisms of neutralization of SVMPs, and for exploring the potential of recombinant antibody fragments for improving the neutralization of local tissue damage in snakebite envenoming., (Copyright © 2014 Elsevier Ltd. All rights reserved.)
- Published
- 2014
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23. Unraveling the processing and activation of snake venom metalloproteinases.
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Portes-Junior JA, Yamanouye N, Carneiro SM, Knittel PS, Sant'Anna SS, Nogueira FC, Junqueira M, Magalhães GS, Domont GB, and Moura-da-Silva AM
- Subjects
- Amino Acid Sequence, Animals, Bothrops anatomy & histology, Bothrops metabolism, Enzyme Activation, Exocrine Glands cytology, Exocrine Glands enzymology, Female, Metalloproteases chemistry, Molecular Sequence Data, Protein Precursors chemistry, Protein Transport, Reptilian Proteins chemistry, Sequence Homology, Amino Acid, Crotalid Venoms enzymology, Metalloproteases metabolism, Protein Precursors metabolism, Reptilian Proteins metabolism
- Abstract
Snake venom metalloproteinases (SVMPs) are zinc-dependent enzymes responsible for most symptoms of human envenoming. Like matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinase (ADAM) proteins, SVMPs are synthesized as zymogens, and enzyme activation is regulated by hydrolysis of their prodomain, but the processing of SVMPs is still unclear. In this study, we attempted to identify the presence of prodomain in different compartments of snake venom glands as zymogens or in the free form to elucidate some mechanism involved in SVMP activation. Using antibodies obtained by immunization with a recombinant prodomain, bands of zymogen molecular mass and prodomain peptides were detected mostly in gland extracts all along the venom production cycle and in the venom collected from the lumen at the peak of venom production. Prodomain was detected in secretory cells mostly in the secretory vesicles near the Golgi. We hypothesize that the processing of SVMPs starts within secretory vesicles and continues in the lumen of the venom gland just after enzyme secretion and involves different steps compared to ADAMs and MMPs but can be used as a model for studying the relevance of peptides resulting from prodomain processing and degradation for controlling the activity of metalloproteinases.
- Published
- 2014
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24. AVE 0991, a non-peptide mimic of angiotensin-(1-7) effects, attenuates pulmonary remodelling in a model of chronic asthma.
- Author
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Rodrigues-Machado MG, Magalhães GS, Cardoso JA, Kangussu LM, Murari A, Caliari MV, Oliveira ML, Cara DC, Noviello ML, Marques FD, Pereira JM, Lautner RQ, Santos RA, and Campagnole-Santos MJ
- Subjects
- Angiotensin II metabolism, Animals, Asthma chemically induced, Asthma immunology, Asthma metabolism, Asthma physiopathology, Bronchoalveolar Lavage Fluid immunology, Bronchoconstriction drug effects, Chronic Disease, Cytokines metabolism, Disease Models, Animal, Hypertrophy, Right Ventricular metabolism, Hypertrophy, Right Ventricular prevention & control, Lung blood supply, Lung immunology, Lung metabolism, Lung physiopathology, Male, Mice, Mice, Inbred BALB C, Molecular Mimicry, Ovalbumin, Proto-Oncogene Mas, Proto-Oncogene Proteins drug effects, Proto-Oncogene Proteins metabolism, Pulmonary Artery immunology, Pulmonary Artery metabolism, Pulmonary Artery physiopathology, Pulmonary Veins immunology, Pulmonary Veins metabolism, Pulmonary Veins physiopathology, Receptors, G-Protein-Coupled drug effects, Receptors, G-Protein-Coupled metabolism, Time Factors, Airway Remodeling drug effects, Angiotensin I pharmacology, Anti-Asthmatic Agents pharmacology, Asthma drug therapy, Imidazoles pharmacology, Lung drug effects, Peptide Fragments pharmacology, Pulmonary Artery drug effects, Pulmonary Veins drug effects
- Abstract
Background and Purpose: AVE 0991 (AVE) is a non-peptide compound, mimic of the angiotensin (Ang)-(1-7) actions in many tissues and pathophysiological states. Here, we have investigated the effect of AVE on pulmonary remodelling in a murine model of ovalbumin (OVA)-induced chronic allergic lung inflammation., Experimental Approach: We used BALB/c mice (6-8 weeks old) and induced chronic allergic lung inflammation by OVA sensitization (20 μg·mouse(-1) , i.p., four times, 14 days apart) and OVA challenge (1%, nebulised during 30 min, three times per·week, for 4 weeks). Control and AVE groups were given saline i.p and challenged with saline. AVE treatment (1 mg·kg(-1) ·per day, s.c.) or saline (100 μL·kg(-1) ·per day, s.c.) was given during the challenge period. Mice were anaesthetized 72 h after the last challenge and blood and lungs collected. In some animals, primary bronchi were isolated to test contractile responses. Cytokines were evaluated in bronchoalveolar lavage (BAL) and lung homogenates., Key Results: Treatment with AVE of OVA sensitised and challenged mice attenuated the altered contractile response to carbachol in bronchial rings and reversed the increased airway wall and pulmonary vasculature thickness and right ventricular hypertrophy. Furthermore, AVE reduced IL-5 and increased IL-10 levels in the BAL, accompanied by decreased Ang II levels in lungs., Conclusions and Implications: AVE treatment prevented pulmonary remodelling, inflammation and right ventricular hypertrophy in OVA mice, suggesting that Ang-(1-7) receptor agonists are a new possibility for the treatment of pulmonary remodelling induced by chronic asthma., (© 2013 The British Pharmacological Society.)
- Published
- 2013
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25. Cloning, expression and characterization of a phospholipase D from Loxosceles gaucho venom gland.
- Author
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Magalhães GS, Caporrino MC, Della-Casa MS, Kimura LF, Prezotto-Neto JP, Fukuda DA, Portes-Junior JA, Neves-Ferreira AG, Santoro ML, and Barbaro KC
- Subjects
- Amino Acid Sequence, Animals, Antibodies, Neutralizing immunology, Base Sequence, Cloning, Molecular, Cross Reactions, Gene Expression, Hemolysis drug effects, Humans, Molecular Sequence Data, Phospholipase D immunology, Phospholipase D metabolism, Phospholipase D pharmacology, Platelet Aggregation drug effects, Rabbits, Sequence Alignment, Sphingomyelin Phosphodiesterase metabolism, Structure-Activity Relationship, Phospholipase D genetics, Spider Venoms genetics
- Abstract
Loxosceles venom comprises a mixture of diverse toxins that induces intense local inflammatory reaction, dermonecrotic injury, platelet aggregation, hemolytic anemia and acute renal failure. Among several toxins in the venom, phospholipases D (PLDs), also called dermonecrotic toxins, are the most important and best studied, since they account for the main effects observed in loxoscelism. Despite their importance, biological analysis of PLDs is hampered by the minute amounts normally purified from the venom, and therefore many efforts have been made to clone those toxins. However, to date, no PLD from Loxosceles gaucho has been obtained in a heterologous system. Thus, in this work we show the cloning of a PLD from L. gaucho venom gland, named LgRec1, which was successfully expressed in a bacterial system. LgRec1 evoked local reaction (edema, erythema, ecchymosis, and paleness), dermonecrosis and hemolysis. It was also able to hydrolyze sphingomyelin and promote platelet aggregation. ELISA and Western blot analysis showed that LgRec1 was recognized by an anti-L. gaucho venom serum, a commercial arachnidic antivenom as well as a monoclonal antibody raised against the dermonecrotic fraction of L. gaucho venom. In addition, LgRec1 demonstrated to be highly immunogenic and antibodies raised against this recombinant toxin inhibited local reaction (~65%) and dermonecrosis (~100%) elicited by L. gaucho whole venom. Since PLDs are considered the major components accounting for the local and systemic envenomation effects caused by spiders from genus Loxosceles, the information provided here may help to understand the mechanisms behind clinical symptomatology., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)
- Published
- 2013
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26. HHV-6: clinical and laboratory investigations and correlations with encephalitis in liver transplant recipients.
- Author
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Magalhães GS, Guardia AC, Sampaio AM, Boin IF, and Stucchi RS
- Subjects
- Adolescent, Adult, Aged, Encephalitis, Viral diagnosis, Encephalitis, Viral physiopathology, Female, Humans, Male, Middle Aged, Polymerase Chain Reaction, Young Adult, Encephalitis, Viral virology, Herpesvirus 6, Human pathogenicity, Liver Transplantation
- Abstract
Objective: Human herpesvirus (HHV) 6 infections and reactivation are emerging factors in neurology. This study aimed to verify the presence of encephalitis associated with HHV-6 positivity by antigenemia or polymerase chain reaction (PCR) in liver transplant recipients., Methods: We analyzed the medical records and laboratory results of 20 recipients with antigenemia or a positive PCR for HHV-6. The range of the transplantation dates was September 2006 to March 2010; the period of the medical records was from the date of transplantation to 1 year thereafter. Encephalitis was diagnosed by these symptoms: fever, mening, signs, seizures, dysphasia, visual and hearing impairment, or sensory and motion alterations. "Possible encephalitis" was considered when the patients had at least 2 of the symptoms. PCR or antigenemia for HHV-6 was not performed with central nervous fluid. The correlation between HHV-6 infection and encephalitis was evaluated with the use of descriptive statistical tests., Results: Symptoms associated with encephalitis occurred in 7/20, patients (35%): 5/20 with fever and 4/20 with mental confusion. Involuntary movements were present in 1 case. The symptoms appeared with in the first 10 days in 6/20 patients and lasted for 1 year., Conclusions: This study showed that symptoms associated with encephalitis occurred in a considerable number of patients with positive PCR and/or antigenemia for HHV-6 after liver transplantation. This correlation needs retrospectie and prospective studies to determine the specific association., (Copyright © 2013 Elsevier Inc. All rights reserved.)
- Published
- 2013
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27. Urinary tract infection analysis in a spinal cord injured population undergoing rehabilitation--how to treat?
- Author
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Martins CF, Bronzatto E, Neto JM, Magalhães GS, D'anconna CA, and Cliquet A Jr
- Subjects
- Adult, Cross-Sectional Studies, Female, Humans, Male, Spinal Cord Injuries epidemiology, Treatment Outcome, Urinary Tract Infections epidemiology, Population Surveillance methods, Spinal Cord Injuries diagnosis, Spinal Cord Injuries rehabilitation, Urinalysis methods, Urinary Tract Infections diagnosis, Urinary Tract Infections rehabilitation
- Abstract
Study Design: Cross sectional study, including 38 outpatients. Standardized questionnaire was used and urine cultures were performed., Objectives: To study spinal cord-injured (SCI) patients bladder management, clinical aspects that symptomatic urinary tract infection (SUTI) may present and asymptomatic bacteriuria (AB) incidence with its antimicrobial susceptibility profile., Setting: Spinal cord injury outpatient rehabilitation clinic., Results: Clean intermittent catheterization is used by 71% of the patients. SUTI may have atypical clinical presentation (shivers, spasticity increase, headaches). In total, 65.7% (N=25) of the patients presented AB. Among these, the microorganisms isolated were resistant mainly to Ampicillin, Sulfamethoxazole-Trimethoprim and Norfloxacin, whose resistance rates were, respectively 73.3%, 60% and 33.3%., Conclusion: Special attention should be given to possible atypical symptoms for SUTI. Although a small amount of urine samples was analyzed, resistance rates against Ampicillin, Sulfamethoxazole-Trimethoprim, Ciprofloxacin and Nitrofurantoin appear to be higher among SCI patients compared to the general population, thus demonstrating the need for continuous monitoring of microorganisms susceptibility, in order to avoid therapeutic failure when dealing with this specific population.
- Published
- 2013
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28. Gene expression of inflammatory mediators induced by jararhagin on endothelial cells.
- Author
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Lopes DS, Faquim-Mauro E, Magalhães GS, Lima IC, Baldo C, Fox JW, Moura-da-Silva AM, and Clissa PB
- Subjects
- Animals, Antigens, CD genetics, Antigens, CD metabolism, Antigens, Differentiation, T-Lymphocyte genetics, Antigens, Differentiation, T-Lymphocyte metabolism, Apoptosis drug effects, Bothrops, Cell Line, Cell Survival, E-Selectin genetics, E-Selectin metabolism, Humans, Inflammation chemically induced, Inflammation drug therapy, Interleukin-8 genetics, Interleukin-8 metabolism, Lectins, C-Type genetics, Lectins, C-Type metabolism, Matrix Metalloproteinase 10 genetics, Matrix Metalloproteinase 10 metabolism, Microarray Analysis methods, Nitric Oxide metabolism, Up-Regulation, Vascular Cell Adhesion Molecule-1 genetics, Vascular Cell Adhesion Molecule-1 metabolism, Bothrops jararaca Venom, Crotalid Venoms toxicity, Gene Expression drug effects, Human Umbilical Vein Endothelial Cells drug effects, Inflammation Mediators pharmacology, Metalloendopeptidases toxicity
- Abstract
Snake venom metalloproteinases (SVMP) are abundant toxins in venoms of viper snakes and play a relevant role in the complex and multifactorial tissue damage characteristic of Viperidae envenoming. Jararhagin, a SVMP isolated from Bothrops jararaca venom, induces a fast onset hemorrhagic lesions acting directly on the capillary vessels, which are disrupted by toxin adhesion and degradation of extracellular matrix proteins like collagen IV. Jararhagin also triggers inflammatory response, where endothelial cells are activated, resulting in the enhanced rolling of circulating leukocytes, nitric oxide generation, prostacyclin production and pro-inflammatory cytokines release. Jararhagin also decreases endothelial cells viability inducing apoptosis (in vitro studies). In the present study we attempted to correlate the effect of sub-apoptotic doses of jararhagin on human umbilical vein endothelial cells (HUVECs) and gene expression of pro-inflammatory mediators, using microarray assay, real time PCR and detection of specific proteins on HUVEC surface or released in the medium. Jararhagin was effective in activate and up-regulate the gene expression of different mediators such as E-selectin, VCAM-1, IL-8, CD69, Ang-2 and MMP-10. Despite the increase in expression of genes coding for such molecules, jararhagin did not induce increased concentrations of E-selectin, VCAM-1 and IL-8 produced or released by endothelial cells. In conclusion, jararhagin is able to activate pro-inflammatory gene transcription on endothelial cells however this stimulus is not sufficient to result in the consequent expression of pro-inflammatory effectors molecules like E-selectin, VCAM-1 and IL-8. The time courses of these events, as well as the doses of jararhagin are important points to be addressed herein., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2012
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29. Engineered mammalian vector to express EGFP-tagged proteins as biomarkers.
- Author
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Magalhães GS, Novo JB, Clissa PB, Della Casa MS, Butera D, and da Silva AM
- Subjects
- Animals, Biomarkers chemistry, Biomarkers metabolism, CHO Cells, Cloning, Molecular, Cricetinae, Cricetulus, Endopeptidases metabolism, Flow Cytometry, Green Fluorescent Proteins chemistry, Green Fluorescent Proteins genetics, Green Fluorescent Proteins isolation & purification, Human Umbilical Vein Endothelial Cells metabolism, Humans, Integrin alphaVbeta3 metabolism, Intercellular Signaling Peptides and Proteins, Microscopy, Fluorescence, Peptides chemistry, Peptides genetics, Peptides isolation & purification, Recombinant Fusion Proteins chemistry, Recombinant Fusion Proteins genetics, Recombinant Fusion Proteins isolation & purification, Transfection, Viper Venoms chemistry, Viper Venoms genetics, Viper Venoms isolation & purification, Green Fluorescent Proteins biosynthesis, Peptides metabolism, Recombinant Fusion Proteins biosynthesis, Viper Venoms biosynthesis
- Abstract
Due to its specialized post-translational machinery, mammalian cells represent an interesting and not fully explored system to express snake toxins. Therefore, in this work, we built up a new mammalian expression vector that enhances the feasibility to use mammalian cells to express proteins as biomarkers. Among the modifications, an Igκ signal peptide and a 6xHis tag were inserted into this vector in order to drive the protein to the supernatant and simplify its purification, respectively. In addition, to facilitate selection of high producing clones and also tag proteins which may function as a biomarker, the sequence of enhanced green fluorescent protein (EGFP) was added. The efficiency of the resulting vector (pToxEGFP) was tested by cloning and expressing the viper venom disintegrin echistatin (Ech) that due to its affinity to integrin αvβ3 was tested as a molecular marker. Expression of EGFP-Ech was achieved in CHO-DXB11 cells resulting in a yield of 22 mg/L. The binding activity of this chimera protein was successfully achieved on human umbilical vein endothelial cells which highly express αvβ3. The results indicate that pToxEGFP may constitute an efficient and versatile expression vector to express tagged proteins with potential biomarker activity.
- Published
- 2012
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30. Diversity of metalloproteinases in Bothrops neuwiedi snake venom transcripts: evidences for recombination between different classes of SVMPs.
- Author
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Moura-da-Silva AM, Furlan MS, Caporrino MC, Grego KF, Portes-Junior JA, Clissa PB, Valente RH, and Magalhães GS
- Subjects
- Amino Acid Sequence, Animals, Base Sequence, Catalytic Domain genetics, Cloning, Molecular, DNA, Complementary, Metalloproteases chemistry, Metalloproteases metabolism, Phylogeny, Protein Processing, Post-Translational, Recombination, Genetic, Sequence Alignment, Sequence Analysis, DNA, Snake Venoms metabolism, Bothrops genetics, Genetic Variation, Metalloproteases genetics, Snake Venoms genetics
- Abstract
Background: Snake venom metalloproteinases (SVMPs) are widely distributed in snake venoms and are versatile toxins, targeting many important elements involved in hemostasis, such as basement membrane proteins, clotting proteins, platelets, endothelial and inflammatory cells. The functional diversity of SVMPs is in part due to the structural organization of different combinations of catalytic, disintegrin, disintegrin-like and cysteine-rich domains, which categorizes SVMPs in 3 classes of precursor molecules (PI, PII and PIII) further divided in 11 subclasses, 6 of them belonging to PII group. This heterogeneity is currently correlated to genetic accelerated evolution and post-translational modifications., Results: Thirty-one SVMP cDNAs were full length cloned from a single specimen of Bothrops neuwiedi snake, sequenced and grouped in eleven distinct sequences and further analyzed by cladistic analysis. Class P-I and class P-III sequences presented the expected tree topology for fibrinolytic and hemorrhagic SVMPs, respectively. In opposition, three distinct segregations were observed for class P-II sequences. P-IIb showed the typical segregation of class P-II SVMPs. However, P-IIa grouped with class P-I cDNAs presenting a 100% identity in the 365 bp at their 5' ends, suggesting post-transcription events for interclass recombination. In addition, catalytic domain of P-IIx sequences segregated with non-hemorrhagic class P-III SVMPs while their disintegrin domain grouped with other class P-II disintegrin domains suggesting independent evolution of catalytic and disintegrin domains. Complementary regions within cDNA sequences were noted and may participate in recombination either at DNA or RNA levels. Proteins predicted by these cDNAs show the main features of the correspondent classes of SVMP, but P-IIb and P-IIx included two additional cysteines cysteines at the C-termini of the disintegrin domains in positions not yet described., Conclusions: In B. neuwiedi venom gland, class P-II SVMPs were represented by three different types of transcripts that may have arisen by interclass recombination with P-I and P-III sequences after the divergence of the different classes of SVMPs. Our observations indicate that exon shuffling or post-transcriptional mechanisms may be driving these recombinations generating new functional possibilities for this complex group of snake toxins.
- Published
- 2011
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31. Structural and biological characterization of Nattectin, a new C-type lectin from the venomous fish Thalassophryne nattereri.
- Author
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Lopes-Ferreira M, Magalhães GS, Fernandez JH, Junqueira-de-Azevedo Ide L, Le Ho P, Lima C, Valente RH, and Moura-da-Silva AM
- Subjects
- Amino Acid Sequence, Animals, Base Sequence, Binding Sites, Calcium metabolism, Cell Movement, Conserved Sequence, Fish Venoms administration & dosage, Fish Venoms chemistry, Fish Venoms isolation & purification, Galactose metabolism, Hemagglutination Tests, Hindlimb pathology, Humans, Immunity, Innate, Immunologic Factors administration & dosage, Immunologic Factors chemistry, Immunologic Factors isolation & purification, Inflammation chemically induced, Inflammation immunology, Lectins, C-Type administration & dosage, Lectins, C-Type chemistry, Lectins, C-Type isolation & purification, Leukocytes drug effects, Leukocytes physiology, Matrix Metalloproteinases metabolism, Mice, Models, Molecular, Molecular Sequence Data, Protein Structure, Tertiary, Sequence Analysis, Protein, Structural Homology, Protein, Batrachoidiformes, Fish Venoms metabolism, Immunologic Factors metabolism, Lectins, C-Type metabolism
- Abstract
Lectins are glycan-binding receptors that recognize glycan epitopes on foreign pathogens and in the host systems. They can be involved in functions that include innate immunity, development, immune regulation and homeostasis. Several lectins have been purified and characterized from fish species. In this work, using cation-exchange chromatography, a galactose-specific lectin belonging to the family of C-type lectins was isolated from the venom of the Brazilian venomous fish Thalassophryne nattereri. Nattectin is a basic, non-glycosilated, 15 kDa monomeric protein. It exhibits hemagglutination activity that is independent of Ca(2+). We also demonstrated a lectin activity for Nattectin in the innate immune system, especially in neutrophil mobilization in mice, indicating that marine organisms are source of immunomodulator agents., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)
- Published
- 2011
- Full Text
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32. "Insularin, a disintegrin from Bothrops insularis venom: inhibition of platelet aggregation and endothelial cell adhesion by the native and recombinant GST-insularin proteins".
- Author
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Della-Casa MS, Junqueira-de-Azevedo I, Butera D, Clissa PB, Lopes DS, Serrano SM, Pimenta DC, Magalhães GS, Ho PL, and Moura-da-Silva AM
- Subjects
- Amino Acid Sequence, Animals, Cell Adhesion drug effects, Cells, Cultured, Cloning, Molecular, Crotalid Venoms biosynthesis, Crotalid Venoms pharmacology, Disintegrins biosynthesis, Disintegrins chemistry, Endothelium, Vascular cytology, Humans, Infant, Newborn, Molecular Sequence Data, Peptide Mapping, Platelet Aggregation Inhibitors chemistry, Recombinant Fusion Proteins biosynthesis, Recombinant Fusion Proteins chemistry, Umbilical Veins cytology, Bothrops, Crotalid Venoms chemistry, Disintegrins pharmacology, Endothelium, Vascular drug effects, Glutathione Transferase metabolism, Platelet Aggregation drug effects, Platelet Aggregation Inhibitors pharmacology, Recombinant Fusion Proteins pharmacology
- Abstract
Insularin (INS) was obtained from Bothrops insularis venom by reversed-phase high-performance liquid chromatography using a C(18) column and characterized as a disintegrin by peptide mass fingerprint and inhibition of ADP-induced platelet aggregation. A cDNA coding for P-II a metalloproteinase/disintegrin was cloned from a cDNA library from B. insularis venom glands. The deduced protein sequence possesses 73 amino acid residues, including the N-terminal, internal peptides of native insularin, the ARGDNP-sequence and 12 cysteines in a conserved alignment. This cDNA fragment was subcloned in the pGEX-4T-1 vector and expressed in a prokaryotic expression system as a fusion protein with glutathione S-transferase (GST-INS). Both native and recombinant insularin inhibited ADP-induced platelet aggregation and endothelial cells (HUVEC) adhesion with similar activities indicating that GST-INS folded correctly and preserved the integrin-binding loop. Insularin may be a tool in studies that involve platelets and endothelial cell adhesion dependent on alphaIIbeta3 and alphavbeta3 integrins., (Copyright © 2010 Elsevier Ltd. All rights reserved.)
- Published
- 2011
- Full Text
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33. Generation of polyclonal antibodies against recombinant human glucocerebrosidase produced in Escherichia coli.
- Author
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Novo JB, Oliveira ML, Magalhães GS, Morganti L, Raw I, and Ho PL
- Subjects
- Animals, Base Sequence, Blotting, Western, COS Cells, Chlorocebus aethiops, DNA Primers, Enzyme-Linked Immunosorbent Assay, HeLa Cells, Humans, Immune Sera, Mice, Mice, Inbred BALB C, Recombinant Proteins biosynthesis, Recombinant Proteins genetics, Antibody Formation, Escherichia coli genetics, Glucosylceramidase immunology
- Abstract
Deficiency of the lysosomal glucocerebrosidase (GCR) enzyme results in Gaucher's disease, the most common inherited storage disorder. Treatment consists of enzyme replacement therapy by the administration of recombinant GCR produced in Chinese hamster ovary cells. The production of anti-GCR antibodies has already been described with placenta-derived human GCR that requires successive chromatographic procedures. Here, we report a practical and efficient method to obtain anti-GCR polyclonal antibodies against recombinant GCR produced in Escherichia coli and further purified by a single step through nickel affinity chromatography. The purified GCR was used to immunize BALB/c mice and the induction of anti-GCR antibodies was evaluated by enzyme-linked immunosorbent assay. The specificity of the antiserum was also evaluated by western blot analysis against recombinant GCR produced by COS-7 cells or against endogenous GCR of human cell lines. GCR was strongly recognized by the produced antibodies, either as cell-associated or as secreted forms. The detected molecular masses of 59-66 kDa are in accordance to the expected size for glycosylated GCR. The GCR produced in E. coli would facilitate the production of polyclonal (shown here) and monoclonal antibodies and their use in the characterization of new biosimilar recombinant GCRs coming in the near future.
- Published
- 2010
- Full Text
- View/download PDF
34. Different regions of the class P-III snake venom metalloproteinase jararhagin are involved in binding to alpha2beta1 integrin and collagen.
- Author
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Tanjoni I, Evangelista K, Della-Casa MS, Butera D, Magalhães GS, Baldo C, Clissa PB, Fernandes I, Eble J, and Moura-da-Silva AM
- Subjects
- Animals, Antibodies, Blocking pharmacology, Antibodies, Monoclonal pharmacology, Blood Platelets drug effects, Collagen drug effects, Crotalid Venoms immunology, Crotalid Venoms pharmacology, Humans, Integrin alpha2beta1 drug effects, K562 Cells drug effects, Metalloendopeptidases immunology, Metalloendopeptidases pharmacology, Platelet Aggregation drug effects, Platelet Aggregation Inhibitors immunology, Platelet Aggregation Inhibitors pharmacology, Protein Binding drug effects, Recombinant Proteins immunology, Recombinant Proteins metabolism, Recombinant Proteins pharmacology, Transfection, Bothrops jararaca Venom, Collagen metabolism, Crotalid Venoms metabolism, Integrin alpha2beta1 metabolism, K562 Cells metabolism, Metalloendopeptidases metabolism, Platelet Aggregation Inhibitors metabolism
- Abstract
SVMPs are multi-domain proteolytic enzymes in which disintegrin-like and cysteine-rich domains bind to cell receptors, plasma or ECM proteins. We have recently reported that jararhagin, a P-III class SVMP, binds to collagen with high affinity through an epitope located within the Da-disintegrin sub-domain. In this study, we evaluated the binding of jararhagin to alpha(2)beta(1) integrin (collagen receptor) using monoclonal antibodies and recombinant jararhagin fragments. In solid phase assays, binding of jararhagin to alpha(2)beta(1) integrin was detectable from concentrations of 20 nM. Using recombinant fragments of jararhagin, only fragment JC76 (residues 344-421), showed a significant binding to recombinant alpha(2)beta(1) integrin. The anti-jararhagin monoclonal antibody MAJar 3 efficiently neutralised binding of jararhagin to collagen, but not to recombinant alpha(2)beta(1) integrin nor to cell-surface-exposed alpha(2)beta(1) integrin (alpha(2)-K562 transfected cells and platelets). The same antibody neutralised collagen-induced platelet aggregation. Our data suggest that jararhagin binding to collagen and alpha(2)beta(1) integrin occurs by two independent motifs, which are located on disintegrin-like and cysteine-rich domains, respectively. Moreover, toxin binding to collagen appears to be sufficient to inhibit collagen-induced platelet aggregation., (Copyright 2009 Elsevier Ltd. All rights reserved.)
- Published
- 2010
- Full Text
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35. Cloning of serine protease cDNAs from Crotalus durissus terrificus venom gland and expression of a functional Gyroxin homologue in COS-7 cells.
- Author
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Yonamine CM, Prieto-da-Silva AR, Magalhães GS, Rádis-Baptista G, Morganti L, Ambiel FC, Chura-Chambi RM, Yamane T, and Camillo MA
- Subjects
- Amino Acid Sequence, Animals, Blotting, Western, COS Cells, Chlorocebus aethiops, Cloning, Molecular, Crotalid Venoms enzymology, Crotalid Venoms genetics, DNA, Complementary genetics, Electrophoresis, Polyacrylamide Gel, Escherichia coli metabolism, Esterases chemistry, Esterases metabolism, Exocrine Glands enzymology, Gene Library, Genetic Vectors, Mice, Molecular Weight, Plasmids genetics, Recombinant Proteins genetics, Serine Endopeptidases genetics, Crotalid Venoms biosynthesis, DNA, Complementary biosynthesis, Exocrine Glands chemistry, Serine Endopeptidases biosynthesis
- Abstract
Gyroxin is one of main serine proteases of Crotalus durissus terrificus venom, representing about 2% of the protein content in the crude venom. It is a 33 kDa glycoprotein with 3.8% by weight of sugar moiety. This toxin induces hemotoxicity in mice and a neurological condition called barrel rotation syndrome. In the present work, we report the molecular cloning of five new nucleotide sequences from a cDNA library of the venom glands of a single specimen of C. d. terrificus. These sequences have been analyzed in silico with respect to their cDNA organization and similarity with other snake venom serine proteases (SVSPs). We also describe a rapid and efficient method for screening vectors for mammalian cell expression, based on the fact that SVSPs are difficult-to-express toxins due to the presence of several disulfide bonds and glycosylation in their structures. Thus, one of the Gyroxin cDNAs was subcloned into pSectag2 HygroA and pED vectors and used to transfect COS-7 cells. Expression of the functional recombinant Gyroxin isoform was achieved with this cell line with esterase activity in the conditioned culture medium, as revealed by immunoblot of secreted protein and standard anti-crotalic serum from Butantan Institute.
- Published
- 2009
- Full Text
- View/download PDF
36. Transcriptome analysis of expressed sequence tags from the venom glands of the fish Thalassophryne nattereri.
- Author
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Magalhães GS, Junqueira-de-Azevedo IL, Lopes-Ferreira M, Lorenzini DM, Ho PL, and Moura-da-Silva AM
- Subjects
- Amino Acid Sequence, Animals, Calcium-Binding Proteins, DNA, Complementary genetics, Fish Proteins chemistry, Fish Proteins genetics, Fish Venoms chemistry, Humans, Lectins, C-Type, Molecular Chaperones, Molecular Sequence Data, Sequence Analysis, DNA, Expressed Sequence Tags, Fish Venoms genetics, Fishes, Poisonous genetics, Gene Expression Profiling, Transcription, Genetic genetics
- Abstract
Thalassophryne nattereri (niquim) is a venomous fish found on the northern and northeastern coasts of Brazil. Every year, hundreds of humans are affected by the poison, which causes excruciating local pain, edema, and necrosis, and can lead to permanent disabilities. In experimental models, T. nattereri venom induces edema and nociception, which are correlated to human symptoms and dependent on venom kininogenase activity; myotoxicity; impairment of blood flow; platelet lysis and cytotoxicity on endothelial cells. These effects were observed with minute amounts of venom. To characterize the primary structure of T. nattereri venom toxins, a list of transcripts within the venom gland was made using the expressed sequence tag (EST) strategy. Here we report the analysis of 775 ESTs that were obtained from a directional cDNA library of T. nattereri venom gland. Of these ESTs, 527 (68%) were related to sequences previously described. These were categorized into 10 groups according to their biological functions. Sequences involved in gene and protein expression accounted for 14.3% of the ESTs, reflecting the important role of protein synthesis in this gland. Other groups included proteins engaged in the assembly of disulfide bonds (0.5%), chaperones involved in the folding of nascent proteins (1.4%), and sequences related to clusterin (1.5%), as well as transcripts related to calcium binding proteins (1.0%). We detected a large cluster (1.3%) related to cocaine- and amphetamine-regulated transcript (CART), a peptide involved in the regulation of food intake. Surprisingly, several retrotransposon-like sequences (1.0%) were found in the library. It may be that their presence accounts for some of the variation in venom toxins. The toxin category (18.8%) included natterins (18%), which are a new group of kininogenases recently described by our group, and a group of C-type lectins (0.8%). In addition, a considerable number of sequences (32%) was not related to sequences in the databases, which indicates that a great number of new toxins and proteins are still to be discovered from this fish venom gland.
- Published
- 2006
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37. Natterins, a new class of proteins with kininogenase activity characterized from Thalassophryne nattereri fish venom.
- Author
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Magalhães GS, Lopes-Ferreira M, Junqueira-de-Azevedo IL, Spencer PJ, Araújo MS, Portaro FC, Ma L, Valente RH, Juliano L, Fox JW, Ho PL, and Moura-da-Silva AM
- Subjects
- Amino Acid Sequence, Animals, Base Sequence, Chromatography, Gel, Electrophoresis, Gel, Two-Dimensional, Fish Venoms chemistry, Fishes, Poisonous, Gene Library, Kallikreins chemistry, Molecular Sequence Data, Sequence Alignment, Batrachoidiformes metabolism, Fish Venoms isolation & purification, Kallikreins isolation & purification
- Abstract
A novel family of proteins with kininogenase activity and unique primary structure was characterized using combined pharmacological, proteomic and transcriptomic approaches of Thalassophryne nattereri fish venom. The major venom components were isolated and submitted to bioassays corresponding to its main effects: nociception and edema. These activities were mostly located in one fraction (MS3), which was further fractionated. The isolated protein, named natterin, was able to induce edema, nociception and cleave human kininogen and kininogen-derived synthetic peptides, releasing kallidin (Lys-bradykinin). The enzymatic digestion was inhibited by kallikrein inhibitors as Trasylol and TKI. Natterin N-terminal peptide showed no similarity with already known proteins present in databanks. Primary structure of natterin was obtained by a transcriptomic approach using a representative cDNA library constructed from T. nattereri venom glands. Several expressed sequence tags (ESTs) were obtained and processed by bioinformatics revealing a major group (18%) of related sequences unknown to gene or protein sequence databases. This group included sequences showing the N-terminus of isolated natterin and was named Natterin family. Analysis of this family allowed us to identify five related sequences, which we called natterin 1-4 and P. Natterin 1 and 2 sequences include the N-terminus of the isolated natterin. Furthermore, internal peptides of natterin 1-3 were found in major spots of whole venom submitted to mass spectrometry/2DGE. Similarly to the ESTs, the complete sequences of natterins did not show any significant similarity with already described tissue kallikreins, kininogenases or any proteinase, all being entirely new. These data present a new task for the knowledge of the action of kininogenases and may help in understanding the mechanisms of T. nattereri fish envenoming, which is an important medical problem in North and Northeast of Brazil.
- Published
- 2005
- Full Text
- View/download PDF
38. A novel human G protein-coupled receptor is over-expressed in prostate cancer.
- Author
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Parmigiani RB, Magalhães GS, Galante PA, Manzini CV, Camargo AA, and Malnic B
- Subjects
- Amino Acid Sequence, Biomarkers, Tumor genetics, Biomarkers, Tumor metabolism, Cell Line, Tumor, Humans, Male, Molecular Sequence Data, Neoplasm Proteins metabolism, Phylogeny, Prostatic Neoplasms metabolism, Receptors, G-Protein-Coupled metabolism, Reverse Transcriptase Polymerase Chain Reaction, Gene Expression Regulation, Neoplastic genetics, Neoplasm Proteins genetics, Prostatic Neoplasms genetics, Receptors, G-Protein-Coupled genetics
- Abstract
G protein-coupled receptors (GPCRs) are involved in a large variety of physiological functions. The number of known members that belong to this large family of receptors has been rapidly increasing. Now, with the availability of the human genome sequence databases, further family members are being identified. We describe the identification of a novel GPCR that shows no significant amino acid identity to any one of the known members of the GPCR superfamily. The gene expression pattern of this receptor is restricted: in normal tissues it is confined to the nervous system and testis, but we also detected gene expression in several tumor types, most notably prostate cancer, suggesting a potential role for this gene as a marker for this disease.
- Published
- 2004
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