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1.
Am J Physiol Regul Integr Comp Physiol ; 317(1): R190-R202, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31091151

RESUMO

Proinflammatory cytokines like interleukin-1ß (IL-1ß) affect the control of breathing. Our aim is to determine the effect of the anti-inflammatory cytokine IL-10 οn the control of breathing. IL-10 knockout mice (IL-10-/-, n = 10) and wild-type mice (IL-10+/+, n = 10) were exposed to the following test gases: hyperoxic hypercapnia 7% CO2-93% O2, normoxic hypercapnia 7% CO2-21% O2, hypoxic hypercapnia 7% CO2-10% O2, and hypoxic normocapnia 3% CO2-10% O2. The ventilatory function was assessed using whole body plethysmography. Recombinant mouse IL-10 (rIL-10; 10 µg/kg) was administered intraperitoneally to wild-type mice (n = 10) 30 min before the onset of gas challenge. IL-10 was administered in neonatal medullary slices (10-30 ng/ml, n = 8). We found that IL-10-/- mice exhibited consistently increased frequency and reduced tidal volume compared with IL-10+/+ mice during room air breathing and in all test gases (by 23.62 to 33.2%, P < 0.05 and -36.23 to -41.69%, P < 0.05, respectively). In all inspired gases, the minute ventilation of IL-10-/- mice was lower than IL-10+/+ (by -15.67 to -22.74%, P < 0.05). The rapid shallow breathing index was higher in IL-10-/- mice compared with IL-10+/+ mice in all inspired gases (by 50.25 to 57.5%, P < 0.05). The intraperitoneal injection of rIL-10 caused reduction of the respiratory rate and augmentation of the tidal volume in room air and also in all inspired gases (by -12.22 to -29.53 and 32.18 to 45.11%, P < 0.05, respectively). IL-10 administration in neonatal rat (n = 8) in vitro rhythmically active medullary slice preparations did not affect either rhythmicity or peak amplitude of hypoglossal nerve discharge. In conclusion, IL-10 may induce a slower and deeper pattern of breathing.


Assuntos
Dióxido de Carbono/farmacologia , Interleucina-10/metabolismo , Oxigênio/farmacologia , Fenômenos Fisiológicos Respiratórios/efeitos dos fármacos , Animais , Encéfalo/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-10/genética , Interleucina-10/farmacologia , Masculino , Bulbo/efeitos dos fármacos , Bulbo/fisiologia , Camundongos , Camundongos Knockout
2.
Mol Hum Reprod ; 23(1): 54-67, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27932551

RESUMO

STUDY QUESTION: Is it possible to improve clinical visualization of phospholipase C zeta (PLCζ) as a diagnostic marker of sperm oocyte activation capacity and male fertility? SUMMARY ANSWER: Poor PLCζ visualization efficacy using current protocols may be due to steric or conformational occlusion of native PLCζ, hindering antibody access, and is significantly enhanced using antigen unmasking/retrieval (AUM) protocols. WHAT IS KNOWN ALREADY: Mammalian oocyte activation is mediated via a series of intracellular calcium (Ca2+) oscillations induced by sperm-specific PLCζ. PLCζ represents not only a potential clinical therapeutic in cases of oocyte activation deficiency but also a diagnostic marker of sperm fertility. However, there are significant concerns surrounding PLCζ antibody specificity and detection protocols. STUDY DESIGN, SIZE DURATION: Two PLCζ polyclonal antibodies, with confirmed PLCζ specificity, were employed in mouse, porcine and human sperm. Experiments evaluated PLCζ visualization efficacy, and whether AUM improved this. Antibodies against two sperm-specific proteins [post-acrosomal WW-binding protein (PAWP) and acrosin] were used as controls. PARTICIPANTS/MATERIALS, SETTING, METHODS: Aldehyde- and methanol-fixed sperm were subject to immunofluorescence analysis following HCl exposure (pH = 0.1-0.5), acid Tyrode's solution exposure (pH = 2.5) or heating in 10 mM sodium citrate solution (pH = 6.0). Fluorescence intensity of at least 300 cells was recorded for each treatment, with three independent repeats. MAIN RESULTS AND THE ROLE OF CHANCE: Despite high specificity for native PLCζ following immunoblotting using epitope-specific polyclonal PLCζ antibodies in mouse, porcine and human sperm, immunofluorescent visualization efficacy was poor. In contrast, sperm markers PAWP and acrosin exhibited relatively impressive results. All methods of AUM on aldehyde-fixed sperm enhanced visualization efficacy for PLCζ compared to visualization efficacy before AUM (P < 0.05 for all AUM interventions), but exerted no significant change upon PAWP or acrosin immunofluorescence following AUM. All methods of AUM enhanced PLCζ visualization efficacy in mouse and human methanol-fixed sperm compared to without AUM (P < 0.05 for all AUM interventions), while no significant change was observed in methanol-fixed porcine sperm before and after. In the absence of aldehyde-induced cross-linkages, such results suggest that poor PLCζ visualization efficacy may be due to steric or conformational occlusion of native PLCζ, hindering antibody access. Importantly, examination of sperm from individual donors revealed that AUM differentially affects observable PLCζ fluorescence, and the proportion of sperm exhibiting detectable PLCζ fluorescence in sperm from different males. LIMITATIONS, REASONS FOR CAUTION: Direct correlation of fertility outcomes with the level of PLCζ in the sperm samples studied was not available. Such analyses would be required in future to determine whether the improved methodology for PLCζ visualization we propose would indeed reflect fertility status. WIDER IMPLICATIONS OF THE FINDINGS: We propose that AUM alters conformational interactions to enhance PLCζ epitope availability and visualization efficacy, supporting prospective application of AUM to reduce misinterpretation in clinical diagnosis of PLCζ-linked male infertility. Our current results suggest that it is perhaps prudent that previous studies investigating links between PLCζ and fertility parameters are re-examined in the context of AUM, and may pave the way for future work to answer significant questions such as how PLCζ appears to be kept in an inactive form in the sperm. LARGE SCALE DATA: Not applicable. STUDY FUNDING/COMPETING INTERESTS: J.K. is supported by a Health Fellowship award from the National Institute for Social Care and Health Research (NISCHR). M.N. is supported by a Marie Curie Intra-European Research Fellowship award. This work was also partly funded by a research grant from Cook Medical Technologies LLC. There are no competing financial interests to declare.


Assuntos
Imunofluorescência/normas , Infertilidade Masculina/enzimologia , Fosfoinositídeo Fosfolipase C/análise , Interações Espermatozoide-Óvulo/fisiologia , Espermatozoides/enzimologia , Acrosina/genética , Acrosina/imunologia , Animais , Anticorpos/química , Especificidade de Anticorpos , Complexo Antígeno-Anticorpo/química , Biomarcadores/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/imunologia , Expressão Gênica , Humanos , Infertilidade Masculina/genética , Masculino , Camundongos , Oócitos/citologia , Oócitos/fisiologia , Fosfoinositídeo Fosfolipase C/química , Fosfoinositídeo Fosfolipase C/genética , Fosfoinositídeo Fosfolipase C/imunologia , Ligação Proteica , Conformação Proteica , Proteínas de Plasma Seminal/genética , Proteínas de Plasma Seminal/imunologia , Espermatozoides/patologia , Suínos , Fixação de Tecidos/métodos
3.
Respir Res ; 18(1): 209, 2017 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-29237457

RESUMO

BACKGROUND: Inspiratory resistive breathing (IRB), a hallmark of obstructive airway diseases, is associated with large negative intrathoracic pressures, due to strenuous contractions of the inspiratory muscles. IRB is shown to induce lung injury in previously healthy animals. Src is a multifunctional kinase that is activated in the lung by mechanical stress. ERK1/2 kinase is a downstream target of Src. We hypothesized that Src is activated in the lung during IRB, mediates ERK1/2 activation and IRB-induced lung injury. METHODS: Anaesthetized, tracheostomized adult rats breathed spontaneously through a 2-way non-rebreathing valve. Resistance was added to the inspiratory port to provide a peak tidal inspiratory pressure of 50% of maximum (inspiratory resistive breathing). Activation of Src and ERK1/2 in the lung was estimated during IRB. Following 6 h of IRB, respiratory system mechanics were measured by the forced oscillation technique and bronchoalveolar lavage (BAL) was performed to measure total and differential cell count and total protein levels. IL-1b and MIP-2a protein levels were measured in lung tissue samples. Wet lung weight to total body weight was measured and Evans blue dye extravasation was estimated to measure lung permeability. Lung injury was evaluated by histology. The Src inhibitor, PP-2 or the inhibitor of ERK1/2 activation, PD98059 was administrated 30 min prior to IRB. RESULTS: Src kinase was activated 30 min after the initiation of IRB. Src inhibition ameliorated the increase in BAL cellularity after 6 h IRB, but not the increase of IL-1ß and MIP-2a in the lung. The increase in BAL total protein and lung injury score were not affected. The increase in tissue elasticity was partly inhibited. Src inhibition blocked ERK1/2 activation at 3 but not at 6 h of IRB. ERK1/2 inhibition ameliorated the increase in BAL cellularity after 6 h of IRB, blocked the increase of IL-1ß and returned Evans blue extravasation and wet lung weight to control values. BAL total protein and the increase in elasticity were partially affected. ERK1/2 inhibition did not significantly change total lung injury score compared to 6 h IRB. CONCLUSIONS: Src and ERK1/2 are activated in the lung following IRB and participate in IRB-induced lung injury.


Assuntos
Lesão Pulmonar Aguda/enzimologia , Resistência das Vias Respiratórias/fisiologia , Inalação/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Quinases da Família src/metabolismo , Lesão Pulmonar Aguda/patologia , Resistência das Vias Respiratórias/efeitos dos fármacos , Animais , Líquido da Lavagem Broncoalveolar , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Inibidores Enzimáticos/farmacologia , Feminino , Inflamação/enzimologia , Inflamação/patologia , Inalação/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Ratos , Quinases da Família src/antagonistas & inibidores
4.
Biochim Biophys Acta ; 1850(11): 2168-76, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26164367

RESUMO

Calmodulin (CaM) is a cytoplasmic calcium sensor that interacts with the cardiac ryanodine receptor (RyR2), a large Ca(2+) channel complex that mediates Ca(2+) efflux from the sarcoplasmic reticulum (SR) to activate cardiac muscle contraction. Direct CaM association with RyR2 is an important physiological regulator of cardiac muscle excitation-contraction coupling and defective CaM-RyR2 protein interaction has been reported in cases of heart failure. Recent genetic studies have identified CaM missense mutations in patients with a history of severe cardiac arrhythmogenic disorders that present divergent clinical features, including catecholaminergic polymorphic ventricular tachycardia (CPVT), long QT syndrome (LQTS) and idiopathic ventricular fibrillation (IVF). Herein, we describe how two CPVT- (N54I & N98S) and three LQTS-associated (D96V, D130G & F142L) CaM mutations result in alteration of their biochemical and biophysical properties. Ca(2+)-binding studies indicate that the CPVT-associated CaM mutations, N54I & N98S, exhibit the same or a 3-fold reduced Ca(2+)-binding affinity, respectively, versus wild-type CaM, whereas the LQTS-associated CaM mutants, D96V, D130G & F142L, display more profoundly reduced Ca(2+)-binding affinity. In contrast, all five CaM mutations confer a disparate RyR2 interaction and modulation of [(3)H]ryanodine binding to RyR2, regardless of CPVT or LQTS association. Our findings suggest that the clinical presentation of CPVT or LQTS associated with these five CaM mutations may involve both altered intrinsic Ca(2+)-binding as well as defective interaction with RyR2.


Assuntos
Calmodulina/genética , Síndrome do QT Longo/etiologia , Mutação , Canal de Liberação de Cálcio do Receptor de Rianodina/fisiologia , Taquicardia Ventricular/etiologia , Animais , Cálcio/metabolismo , Suínos
5.
Biochim Biophys Acta Gen Subj ; 1867(4): 130313, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36693454

RESUMO

Calmodulin (CaM) modulates the activity of several proteins that play a key role in excitation-contraction coupling (ECC). In cardiac muscle, the major binding partner of CaM is the type-2 ryanodine receptor (RyR2) and altered CaM binding contributes to defects in sarcoplasmic reticulum (SR) calcium (Ca2+) release. Many genetic studies have reported a series of CaM missense mutations in patients with a history of severe arrhythmogenic cardiac disorders. In the present study, we generated four missense CaM mutants (CaMN98I, CaMD132E, CaMD134H and CaMQ136P) and we used a CaM-RyR2 co-immunoprecipitation and a [3H]ryanodine binding assay to directly compare the relative RyR2-binding of wild type and mutant CaM proteins and to investigate the functional effects of these CaM mutations on RyR2 activity. Furthermore, isothermal titration calorimetry (ITC) experiments were performed to investigate and compare the interactions of the wild-type and mutant CaM proteins with various synthetic peptides located in the well-established RyR2 CaM-binding region (3584-3602aa), as well as another CaM-binding region (4255-4271aa) of human RyR2. Our data revealed that all four CaM mutants displayed dramatically reduced RyR2 interaction and defective modulation of [3H]ryanodine binding to RyR2, regardless of LQTS or CPVT association. Moreover, our isothermal titration calorimetry ITC data suggest that RyR2 3584-3602aa and 4255-4271aa regions interact with significant affinity with wild-type CaM, in the presence and absence of Ca2+, two regions that might contribute to a putative intra-subunit CaM-binding pocket. In contrast, screening the interaction of the four arrhythmogenic CaM mutants with two synthetic peptides that correspond to these RyR2 regions, revealed disparate binding properties and signifying differential mechanisms that contribute to reduced RyR2 association.


Assuntos
Calmodulina , Canal de Liberação de Cálcio do Receptor de Rianodina , Humanos , Arritmias Cardíacas/genética , Arritmias Cardíacas/metabolismo , Sinalização do Cálcio , Calmodulina/química , Mutação , Rianodina , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo
6.
Int J Chron Obstruct Pulmon Dis ; 18: 2321-2333, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37876659

RESUMO

Introduction: Resistive breathing (RB) is characterized by forceful contractions of the inspiratory muscles, mainly the diaphragm, resulting in large negative intrathoracic pressure and mechanical stress imposed on the lung. We have shown that RB induces lung injury in healthy animals. Whether RB exerts additional injurious effects when added to pulmonary or extrapulmonary lung injury is unknown. Our aim was to study the synergistic effect of RB on lipopolysaccharide (LPS)-induced lung injury. Methods: C57BL/6 mice inhaled an LPS aerosol (10mg/3mL) or received an intraperitoneal injection of LPS (10 mg/kg). Mice were then anaesthetized, the trachea was surgically exposed, and a nylon band of a specified length was sutured around the trachea, to provoke a reduction of the surface area at 50%. RB through tracheal banding was applied for 24 hours. Respiratory system mechanics were measured, BAL was performed, and lung sections were evaluated for histological features of lung injury. Results: LPS inhalation increased BAL cellularity, mainly neutrophils (p < 0.001 to ctr), total protein and IL-6 in BAL (p < 0.001 and p < 0.001, respectively) and increased the lung injury score (p = 0.001). Lung mechanics were not altered. Adding RB to inhaled LPS further increased BAL cellularity (p < 0.001 to LPS inh.), total protein (p = 0.016), lung injury score (p = 0.001) and increased TNFa levels in BAL (p = 0.011). Intraperitoneal LPS increased BAL cellularity, mainly macrophages (p < 0.001 to ctr.), total protein levels (p = 0.017), decreased static compliance (p = 0.004) and increased lung injury score (p < 0.001). Adding RB further increased histological features of lung injury (p = 0.022 to LPS ip). Conclusion: Resistive breathing exerts synergistic injurious effects when combined with inhalational LPS-induced lung injury, while the additive effect on extrapulmonary lung injury is less prominent.


Assuntos
Lesão Pulmonar , Doença Pulmonar Obstrutiva Crônica , Camundongos , Animais , Lesão Pulmonar/metabolismo , Endotoxinas/metabolismo , Lipopolissacarídeos , Líquido da Lavagem Broncoalveolar , Doença Pulmonar Obstrutiva Crônica/metabolismo , Camundongos Endogâmicos C57BL , Aerossóis e Gotículas Respiratórios , Pulmão/metabolismo
7.
Biochem J ; 438(3): 545-53, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21692749

RESUMO

Sperm PLCζ (phospholipase Cζ) is a distinct phosphoinositide-specific PLC isoform that is proposed to be the physiological trigger of egg activation and embryo development at mammalian fertilization. Recombinant PLCζ has the ability to trigger Ca²âº oscillations when expressed in eggs, but it is not known how PLCζ activity is regulated in sperm or eggs. In the present study, we have transfected CHO (Chinese-hamster ovary) cells with PLCζ fused with either YFP (yellow fluorescent protein) or luciferase and found that PLCζ-transfected cells did not display cytoplasmic Ca²âº oscillations any differently from control cells. PLCζ expression was not associated with changes in CHO cell resting Ca²âº levels, nor with a significantly changed Ca²âº response to extracellular ATP compared with control cells transfected with either YFP alone, a catalytically inactive PLCζ or luciferase alone. Sperm extracts containing PLCζ also failed to cause Ca²âº oscillations in CHO cells. Despite these findings, PLCζ-transfected CHO cell extracts exhibited high recombinant protein expression and PLC activity. Furthermore, either PLCζ-transfected CHO cells or derived cell extracts could specifically cause cytoplasmic Ca²âº oscillations when microinjected into mouse eggs. These data suggest that PLCζ-mediated Ca²âº oscillations may require specific factors that are only present within the egg cytoplasm or be inhibited by factors present only in somatic cell lines.


Assuntos
Cálcio/metabolismo , Oócitos/citologia , Fosfoinositídeo Fosfolipase C/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cricetinae , Citoplasma/genética , Citoplasma/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Mamíferos/genética , Mamíferos/metabolismo , Camundongos , Oócitos/metabolismo , Fosfoinositídeo Fosfolipase C/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transfecção
8.
Artigo em Inglês | MEDLINE | ID: mdl-35210764

RESUMO

INTRODUCTION: TRPV4 channels are calcium channels, activated by mechanical stress, that have been implicated in the pathogenesis of pulmonary inflammation. During resistive breathing (RB), increased mechanical stress is imposed on the lung, inducing lung injury. The role of TRPV4 channels in RB-induced lung injury is unknown. MATERIALS AND METHODS: Spontaneously breathing adult male C57BL/6 mice were subjected to RB by tracheal banding. Following anaesthesia, mice were placed under a surgical microscope, the surface area of the trachea was measured and a nylon band was sutured around the trachea to reduce area to half. The specific TRPV4 inhibitor, HC-067047 (10 mg/kg ip), was administered either prior to RB and at 12 hrs following initiation of RB (preventive) or only at 12 hrs after the initiation of RB (therapeutic protocol). Lung injury was assessed at 24 hrs of RB, by measuring lung mechanics, total protein, BAL total and differential cell count, KC and IL-6 levels in BAL fluid, surfactant Protein (Sp)D in plasma and a lung injury score by histology. RESULTS: RB decreased static compliance (Cst), increased total protein in BAL (p < 0.001), total cell count due to increased number of both macrophages and neutrophils, increased KC and IL-6 in BAL (p < 0.001 and p = 0.01, respectively) and plasma SpD (p < 0.0001). Increased lung injury score was detected. Both preventive and therapeutic HC-067047 administration restored Cst and inhibited the increase in total protein, KC and IL-6 levels in BAL fluid, compared to RB. Preventive TRPV4 inhibition ameliorated the increase in BAL cellularity, while therapeutic TRPV4 inhibition exerted a partial effect. TRPV4 inhibition blunted the increase in plasma SpD (p < 0.001) after RB and the increase in lung injury score was also inhibited. CONCLUSION: TRPV4 inhibition exerts protective effects against RB-induced lung injury.


Assuntos
Lesão Pulmonar , Doença Pulmonar Obstrutiva Crônica , Animais , Humanos , Pulmão , Lesão Pulmonar/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doença Pulmonar Obstrutiva Crônica/metabolismo , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/farmacologia
9.
World J Methodol ; 11(5): 243-262, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34631482

RESUMO

The term "IgY technology" was introduced in the literature in the mid 1990s to describe a procedure involving immunization of avian species, mainly laying hens and consequent isolation of the polyclonal IgYs from the "immune" egg yolk (thus avoiding bleeding and animal stress). IgYs have been applied to various fields of medicine and biotechnology. The present article will deal with specific aspects of IgY technology, focusing on the currently reported methods for developing, isolating, evaluating and storing polyclonal IgYs. Other topics such as current information on isolation protocols or evaluation of IgYs from different avian species are also discussed. Specific advantages of IgY technology (e.g., novel antibody specificities that may emerge via the avian immune system) will also be discussed. Recent in vitro applications of polyclonal egg yolk-derived IgYs to the field of disease diagnosis in human and veterinary medicine through in vitro immunodetection of target biomolecules will be presented. Moreover, ethical aspects associated with animal well-being as well as new promising approaches that are relevant to the original IgY technology (e.g., development of monoclonal IgYs and IgY-like antibodies through the phage display technique or in transgenic chickens) and future prospects in the area will also be mentioned.

10.
Vaccines (Basel) ; 9(11)2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34835209

RESUMO

The development of peptide-based vaccines for treating human neurodegenerative diseases has been the eventual aim of many research endeavors, although no active immunotherapies have been approved for clinical use till now. A typical example of such endeavors is the effort to develop vaccines for Alzheimer's disease based on the beta-amyloid peptide, which continues to be intensively investigated despite previous setbacks. In this paper, recent developments in peptide-based vaccines which target beta-amyloid as well as tau protein and α-synuclein are presented. Particular focus has been directed toward peptide epitopes and formulation systems selected/developed and employed to enhance vaccine efficacy and safety. Results from both, human clinical trials and animal preclinical studies conducted mainly in transgenic mice have been included. Future perspectives on the topic are also briefly discussed.

11.
Int J Chron Obstruct Pulmon Dis ; 15: 1679-1688, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764913

RESUMO

Introduction: Resistive breathing (RB), the pathophysiologic hallmark of chronic obstructive pulmonary disease (COPD), especially during exacerbations, is associated with significant inflammation and mechanical stress on the lung. Mechanical forces are implicated in the progression of emphysema that is a major pathologic feature of COPD. We hypothesized that resistive breathing exacerbates emphysema. Methods: C57BL/6 mice were exposed to 0.75 units of pancreatic porcine elastase intratracheally to develop emphysema. Resistive breathing was applied by suturing a nylon band around the trachea to reduce surface area to half for the last 24 or 72 hours of a 21-day time period after elastase treatment in total. Following RB (24 or 72 hours), lung mechanics were measured and bronchoalveolar lavage (BAL) was performed. Emphysema was quantified by the mean linear intercept (Lm) and the destructive index (DI) in lung tissue sections. Results: Following 21 days of intratracheal elastase exposure, Lm and DI increased in lung tissue sections [Lm (µm), control 39.09±0.76, elastase 62.05±2.19, p=0.003 and DI, ctr 30.95±2.75, elastase 73.12±1.75, p<0.001]. RB for 72 hours further increased Lm by 64% and DI by 19%, compared to elastase alone (p<0.001 and p=0.02, respectively). RB induced BAL neutrophilia in elastase-treated mice. Static compliance (Cst) increased in elastase-treated mice [Cst (mL/cmH2O), control 0.067±0.001, elastase 0.109±0.006, p<0.001], but superimposed RB decreased Cst, compared to elastase alone [Cst (mL/cmH2O), elastase+RB24h 0.090±0.004, p=0.006 to elastase, elastase+RB72h 0.090±0.005, p=0.006 to elastase]. Conclusion: Resistive breathing augments pulmonary inflammation and emphysema in an elastase-induced emphysema mouse model.


Assuntos
Enfisema , Doença Pulmonar Obstrutiva Crônica , Enfisema Pulmonar , Resistência das Vias Respiratórias , Animais , Modelos Animais de Doenças , Pulmão , Camundongos , Camundongos Endogâmicos C57BL , Enfisema Pulmonar/induzido quimicamente , Suínos
12.
Heliyon ; 5(10): e02616, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31720448

RESUMO

Prothymosin alpha (ProTα) is a highly conserved polypeptide (109 amino acids in humans) with diagnostic and therapeutic potential; ProTα exerts intra- and extra-cellular biological functions associated with cell proliferation, apoptosis and immune regulation, while it has been suggested to act as a damage-associated molecular pattern (DAMP) or alarmin. In this work, chicken polyclonal anti-ProTα antibodies that had been developed several years ago were immunochemically evaluated and proven to retain immunoreactivity for ProTα, with remarkable thermal and pH stability. Moreover, the antibodies showed practically no cross-reactivity with a series of ProTα-fragments, eventually intracellularly produced -such as ProTα[1-28] (also known as Tα1) and ProTα[100-109], which exert per se biological activity and might be present in biological samples along with the intact molecule, being therefore highly specific for whole-length ProTα. Based on the above antibodies (IgYs-3e), a highly specific competitive ProTα-ELISA with well-studied analytical characteristics (intra- and inter-assay CVs: ≤5% and ≤12%, respectively, limit of detection: 2.1 ng/mL, recovery: 88-104%) was developed. The new ProTα-ELISA was applied to the analysis of supernatants of HeLa cells driven to necrosis; intact ProTα was measured in cell culture supernatants, at levels that seemed to depend on % cell necrosis.

13.
Inflammation ; 41(5): 1873-1887, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29974374

RESUMO

Inspiratory resistive breathing (IRB), a hallmark of obstructive airway diseases, is associated with strenuous contractions of the inspiratory muscles and increased negative intrathoracic pressures that act as an injurious stimulus to the lung. We have shown that IRB induces pulmonary inflammation in healthy animals. p38 kinase is activated in the lung under stress. We hypothesized that p38 is activated during IRB and contributes to IRB-induced pulmonary inflammation. Anesthetized, tracheostomized rats breathed spontaneously through a two-way valve. Resistance was connected to the inspiratory port to provoke a peak tidal inspiratory pressure 50% of maximum. Following 3 and 6 h of IRB, respiratory system mechanics were measured and bronchoalveolar lavage (BAL) was performed. Phosphorylated p38, TNF-α, and MIP-2α were detected in lung tissue. Lung injury was estimated histologically. SB203580 (p38 inhibitor) was administered prior to IRB (1 mg kg-1). Six hours of IRB increased phosphorylated p38 in the lung, compared with quietly breathing controls (p = 0.001). Six hours of IRB increased the numbers of macrophages and neutrophils (p = 0.01 and p = 0.005) in BAL fluid. BAL protein levels and lung elasticity increased after both 3 and 6 h IRB. TNF-α and MIP-2α increased after 6 h of IRB (p = 0.01 and p < 0.001, respectively). Increased lung injury score was detected at 6 h IRB. SB203580 administration blocked the increase of neutrophils and macrophages at 6 h IRB (p = 0.01 and p = 0.005 to 6 h IRB) but not the increase in BAL protein and elasticity. TNF-α, MIP-2α, and injury score at 6 h IRB returned to control. p38 activation contributes to IRB-induced pulmonary inflammation.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Inalação , Pneumonia/tratamento farmacológico , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Animais , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Quimiocina CXCL2/análise , Inibidores Enzimáticos/farmacologia , Imidazóis/farmacologia , Lesão Pulmonar , Macrófagos , Neutrófilos , Pneumonia/etiologia , Piridinas/farmacologia , Ratos , Fator de Necrose Tumoral alfa/análise , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
14.
Int J Chron Obstruct Pulmon Dis ; 12: 2207-2220, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28814849

RESUMO

INTRODUCTION: Resistive breathing (RB), a hallmark of obstructive airway diseases, is characterized by strenuous contractions of the inspiratory muscles that impose increased mechanical stress on the lung. RB is shown to induce pulmonary inflammation in previous healthy animals. Tiotropium bromide, an anticholinergic bronchodilator, is also shown to exert anti-inflammatory effects. The effect of tiotropium on RB-induced pulmonary inflammation is unknown. METHODS: Adult rats were anesthetized, tracheostomized and breathed spontaneously through a two-way non-rebreathing valve. Resistances were connected to the inspiratory and/or expiratory port, to produce inspiratory resistive breathing (IRB) of 40% or 50% Pi/Pi,max (40% and 50% IRB), expiratory resistive breathing (ERB) of 60% Pe/Pe,max (60% ERB) or combined resistive breathing (CRB) of both 40% Pi/Pi,max and 60% Pe/Pe,max (40%/60% CRB). Tiotropium aerosol was inhaled prior to RB. After 6 h of RB, mechanical parameters of the respiratory system were measured and bronchoalveolar lavage (BAL) was performed. IL-1ß and IL-6 protein levels were measured in lung tissue. Lung injury was estimated histologically. RESULTS: In all, 40% and 50% IRB increased macrophage and neutrophil counts in BAL and raised IL-1ß and IL-6 lung levels, tissue elasticity, BAL total protein levels and lung injury score. Tiotropium attenuated BAL neutrophil number, IL-1ß, IL-6 levels and lung injury score increase at both 40% and 50% IRB. The increase in macrophage count and protein in BAL was only reversed at 40% IRB, while tissue elasticity was not affected. In all, 60% ERB raised BAL neutrophil count and total protein and reduced macrophage count. IL-1ß and IL-6 levels and lung injury score were increased. Tiotropium attenuated these alterations, except for the decrease in macrophage count and the increase in total protein level. In all, 40%/60% CRB increased macrophage and neutrophil count in BAL, IL-1ß and IL-6 levels, tissue elasticity, total protein in BAL and histological injury score. Tiotropium attenuated the aforementioned alterations. CONCLUSION: Tiotropium inhalation attenuates RB-induced pulmonary inflammation.


Assuntos
Resistência das Vias Respiratórias , Anti-Inflamatórios/administração & dosagem , Pneumopatias Obstrutivas/prevenção & controle , Lesão Pulmonar/prevenção & controle , Pulmão/efeitos dos fármacos , Antagonistas Muscarínicos/administração & dosagem , Pneumonia/prevenção & controle , Ventilação Pulmonar , Respiração Artificial/efeitos adversos , Brometo de Tiotrópio/administração & dosagem , Administração por Inalação , Aerossóis , Animais , Modelos Animais de Doenças , Feminino , Mediadores da Inflamação/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Pulmão/metabolismo , Pulmão/fisiopatologia , Pneumopatias Obstrutivas/etiologia , Pneumopatias Obstrutivas/metabolismo , Pneumopatias Obstrutivas/fisiopatologia , Lesão Pulmonar/etiologia , Lesão Pulmonar/metabolismo , Lesão Pulmonar/fisiopatologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Pneumonia/etiologia , Pneumonia/metabolismo , Pneumonia/fisiopatologia , Ratos , Índice de Gravidade de Doença
15.
FEBS Lett ; 588(17): 2898-902, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-25036739

RESUMO

Calmodulin (CaM) association with the cardiac muscle ryanodine receptor (RyR2) regulates excitation-contraction coupling. Defective CaM-RyR2 interaction is associated with heart failure. A novel CaM mutation (CaM(F90L)) was recently identified in a family with idiopathic ventricular fibrillation (IVF) and early onset sudden cardiac death. We report the first biochemical characterization of CaM(F90L). F90L confers a deleterious effect on protein stability. Ca(2+)-binding studies reveal reduced Ca(2+)-binding affinity and a loss of co-operativity. Moreover, CaM(F90L) displays reduced RyR2 interaction and defective modulation of [(3)H]ryanodine binding. Hence, dysregulation of RyR2-mediated Ca(2+) release via aberrant CaM(F90L)-RyR2 interaction is a potential mechanism that underlies familial IVF.


Assuntos
Calmodulina/genética , Calmodulina/metabolismo , Morte Súbita Cardíaca , Mutação , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Fibrilação Ventricular/genética , Sítios de Ligação , Cálcio/metabolismo , Calmodulina/química , Humanos , Modelos Moleculares , Conformação Proteica , Retículo Sarcoplasmático/metabolismo
16.
Fertil Steril ; 99(1): 76-85, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22999959

RESUMO

OBJECTIVE: To determine the effect of infertility-linked sperm phospholipase Cζ (PLCζ) mutations on their ability to trigger oocyte Ca(2+) oscillations and development, and also to evaluate the potential therapeutic utility of wild-type, recombinant PLCζ protein for rescuing failed oocyte activation and embryo development. DESIGN: Test of a novel therapeutic approach to male factor infertility. SETTING: University medical school research laboratory. PATIENT(S): Donated unfertilized human oocytes from follicle reduction. INTERVENTION(S): Microinjection of oocytes with recombinant human PLCζ protein or PLCζ cRNA and a Ca(2+)-sensitive fluorescent dye. MAIN OUTCOME MEASURE(S): Measurement of the efficacy of mutant and wild-type PLCζ-mediated enzyme activity, oocyte Ca(2+) oscillations, activation, and early embryo development. RESULT(S): In contrast to the wild-type protein, mutant forms of human sperm PLCζ display aberrant enzyme activity and a total failure to activate unfertilized oocytes. Subsequent microinjection of recombinant human PLCζ protein reliably triggers the characteristic pattern of cytoplasmic Ca(2+) oscillations at fertilization, which are required for normal oocyte activation and successful embryo development to the blastocyst stage. CONCLUSION(S): Dysfunctional sperm PLCζ cannot trigger oocyte activation and results in male factor infertility, so a potential therapeutic approach is oocyte microinjection of active, wild-type PLCζ protein. We have demonstrated that recombinant human PLCζ can phenotypically rescue failed activation in oocytes that express dysfunctional PLCζ, and that this intervention culminates in efficient blastocyst formation.


Assuntos
Infertilidade Masculina/tratamento farmacológico , Oócitos/efeitos dos fármacos , Fosfoinositídeo Fosfolipase C/farmacologia , Fosfoinositídeo Fosfolipase C/uso terapêutico , Interações Espermatozoide-Óvulo/efeitos dos fármacos , Animais , Cálcio/metabolismo , Citoplasma/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/fisiologia , Feminino , Humanos , Técnicas In Vitro , Infertilidade Masculina/fisiopatologia , Masculino , Camundongos , Microinjeções , Modelos Animais , Mutação/genética , Oócitos/metabolismo , Fosfoinositídeo Fosfolipase C/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Interações Espermatozoide-Óvulo/fisiologia
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