RESUMO
This study evaluated the effects of Bifidobacterium longum 51A on the intestinal mucosa and inflammatory response in experimental colitis. Colitis was induced by administration of 3.5% dextran sodium sulphate (DSS) solution for 7 days. Two periods of administration were performed: treatment (T) group, mice received Bifidobacterium only during disease induction (7 days); total treatment (TT) group, mice received Bifidobacterium for 10 days before and during disease induction. The probiotic effects on intestinal permeability, inflammatory infiltrate, histological analysis, cytokines, chemokines and sIgA were evaluated. Bifidobacterium administration in the T group showed reduction in intestinal permeability and lower IL-1ß, myeloperoxidase, and eosinophil peroxidase levels compared to those in the colitis group (P<0.05). Bifidobacterium administration in the TT group attenuated severe lesions in the colon and reduced eosinophil peroxidase level (P<0.05). B. longum 51A treatment modality was more effective than total treatment and reduced the inflammatory response and its consequences on intestinal epithelium.
Assuntos
Bifidobacterium longum , Doenças Inflamatórias Intestinais/tratamento farmacológico , Probióticos/uso terapêutico , Animais , Colite/induzido quimicamente , Colo/efeitos dos fármacos , Colo/microbiologia , Colo/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Peroxidase de Eosinófilo/metabolismo , Feminino , Imunoglobulina A Secretora/metabolismo , Inflamação/tratamento farmacológico , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/microbiologia , Interleucina-1beta/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Intestinos/efeitos dos fármacos , Intestinos/patologia , Camundongos , Camundongos Endogâmicos BALB C , Peroxidase/metabolismoRESUMO
Studies have shown autophagy participation in the immunopathology of inflammatory diseases. However, autophagy role in asthma and in eosinophil extracellular traps (EETs) release is poorly understood. Here, we attempted to investigate the autophagy involvement in EETs release and in lung inflammation in an experimental asthma model. Mice were sensitized with ovalbumin (OVA), followed by OVA challenge. Before the challenge with OVA, mice were treated with an autophagy inhibitor, 3-methyladenine (3-MA). We showed that 3-MA treatment decreases the number of eosinophils, eosinophil peroxidase (EPO) activity, goblet cells hyperplasia, proinflammatory cytokines, and nuclear factor kappa B (NFκB) p65 immunocontent in the lung. Moreover, 3-MA was able to improve oxidative stress, mitochondrial energy metabolism, and Na+ , K+ -ATPase activity. We demonstrated that treatment with autophagy inhibitor 3-MA reduced EETs formation in the airway. On the basis of our results, 3-MA treatment can be an interesting alternative for reducing lung inflammation, oxidative stress, mitochondrial damage, and EETs formation in asthma.
Assuntos
Adenina/análogos & derivados , Antiasmáticos/farmacologia , Asma/tratamento farmacológico , Autofagia/imunologia , Armadilhas Extracelulares/imunologia , Adenina/farmacologia , Animais , Asma/induzido quimicamente , Asma/patologia , Líquido da Lavagem Broncoalveolar/citologia , Citocinas/metabolismo , Modelos Animais de Doenças , Metabolismo Energético/efeitos dos fármacos , Peroxidase de Eosinófilo/metabolismo , Eosinófilos/imunologia , Feminino , Células Caliciformes/patologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/metabolismo , Ovalbumina , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição RelA/metabolismoRESUMO
In asthma, there are high levels of inflammatory mediators, reactive oxygen species (ROS), and eosinophil extracellular traps (EETs) formation in airway. Here, we attempted to investigate the ROS involvement in EETs release and airway inflammation in OVA-challenged mice. Before the intranasal challenge with ovalbumin (OVA), animals were treated with two ROS inhibitors, N-acetylcysteine (NAC) or diphenyleneiodonium (DPI). We showed that NAC treatment reduced inflammatory cells in lung. DPI and NAC treatments reduced eosinophil peroxidase (EPO), goblet cells hyperplasia, proinflammatory cytokines, NFκB p65 immunocontent, and oxidative stress in lung. However, only the NAC treatment improved mitochondrial energy metabolism. Moreover, the treatments with DPI and NAC reduced EETs release in airway. This is the first study to show that ROS are needed for EETs formation in asthma. Based on our results, NAC and DPI treatments can be an interesting alternative for reducing airway inflammation, mitochondrial damage, and EETs release in asthma.
Assuntos
Asma/patologia , Eosinófilos/metabolismo , Armadilhas Extracelulares/metabolismo , Pulmão/patologia , Espécies Reativas de Oxigênio/metabolismo , Acetilcisteína/farmacologia , Animais , Citocinas/metabolismo , Metabolismo Energético/fisiologia , Peroxidase de Eosinófilo/metabolismo , Feminino , Células Caliciformes/patologia , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/metabolismo , Oniocompostos/farmacologia , Ovalbumina/toxicidade , Estresse Oxidativo/fisiologia , Fator de Transcrição RelA/metabolismoRESUMO
Asthma is an allergic inflammation driven by the Th2 immune response with release of cytokines such as IL-4 and IL-13, which contribute to the airflow limitations and airway hyperresponsiveness (AHR). The involvement of oxidative stress in this process is well-established, but the specific role of the superoxide anion and nitric oxide in asthma are poorly understood. Thus, the aim of this study was to investigate the mechanisms underlying the superoxide anion/nitric oxide production and detoxification in a murine asthma model. BALB/c male mice were sensitised and challenged with ovalbumin (OVA). Pretreatments with either apocynin (14 mg/kg) or allopurinol (25 mg/kg) (superoxide anion synthesis inhibitors), aminoguanidine (50 mg/kg) (nitric oxide synthesis inhibitor) or diethyldithiocarbamate (100 mg/kg) (superoxide dismutase inhibitor) were performed 1 h before the challenge. Our data showed that apocynin and allopurinol ameliorated AHR and reduced eosinophil peroxidase, as well as IL-4 and IL-13 levels. Apocynin also abrogated leukocyte peribronchiolar infiltrate and increased IL-1ß secretion. Aminoguanidine preserved lung function and shifted the Th2 to the Th1 response with a reduction of IL-4 and IL-13 and increase in IL-1ß production. Diethyldithiocarbamate prevented neither allergen-induced AHR nor eosinophil peroxidase (EPO) generation. All treatments protected against oxidative damage observed by a reduction in TBARS levels. Taken together, these results suggest that AHR in an asthma model can be avoided by the down-regulation of superoxide anion and nitric oxide synthesis in a mechanism that is independent of a redox response. This down-regulation is also associated with a transition in the typical immunological Th2 response toward the Th1 profile.
Assuntos
Asma/imunologia , Inflamação/imunologia , Óxido Nítrico/antagonistas & inibidores , Hipersensibilidade Respiratória/imunologia , Superóxidos/antagonistas & inibidores , Acetofenonas/administração & dosagem , Alopurinol/administração & dosagem , Animais , Asma/metabolismo , Asma/patologia , Modelos Animais de Doenças , Peroxidase de Eosinófilo/imunologia , Peroxidase de Eosinófilo/metabolismo , Guanidinas/administração & dosagem , Humanos , Hipersensibilidade/imunologia , Hipersensibilidade/metabolismo , Hipersensibilidade/patologia , Inflamação/metabolismo , Inflamação/patologia , Interleucina-13/imunologia , Interleucina-13/metabolismo , Interleucina-1beta/imunologia , Interleucina-1beta/metabolismo , Interleucina-4/imunologia , Interleucina-4/metabolismo , Camundongos , Óxido Nítrico/imunologia , Ovalbumina/imunologia , Estresse Oxidativo/imunologia , Espécies Reativas de Oxigênio/imunologia , Espécies Reativas de Oxigênio/metabolismo , Hipersensibilidade Respiratória/metabolismo , Hipersensibilidade Respiratória/patologia , Superóxidos/imunologia , Células Th1/imunologia , Células Th2/imunologiaRESUMO
Myeloperoxidase (MPO) and eosinophil peroxidase (EPO) are enzymes present in neutrophil and eosinophil leukocytes, respectively. Here, we present the development of a sensitive and specific assay for determination of the halogenating enzymatic activity of MPO and EPO based on the electrophilic attack of HOCl and HOBr on aromatic ring of dansylglycine (DG). We found that the intrinsic fluorescence of DG was promptly depleted by the action of these acids. In the presence of the enzymes, the fluorescence bleaching was dependent of chloride (Cl-) and bromide (Br-), which makes the assay able to distinguish the halogenating from the peroxidase activity. A linear correlation was obtained between the hydrogen peroxide (H2O2) concentration and the fluorescent decay. Similarly, the enzyme activity was measured by keeping constant H2O2. The method was applied for studding MPO/EPO specific inhibitors as 5-fluortryptamine (reversible inhibitor) and 4-hydroxybenzhydrazide (irreversible inhibitor). Differently of the taurine chloramine/3,3',5,5'-tetramethylbenzidine assay, which is among the most used technique, the dansylglycine assay was able to differentiate these inhibitors based on their kinetic behavior. In conclusion, this assay can differentiate the peroxidase and halogenating activity of MPO and EPO. Moreover, the method is adequate for real-time measurement of the production of HOCl and HOBr.
Assuntos
Brometos/química , Cloretos/química , Peroxidase de Eosinófilo/metabolismo , Corantes Fluorescentes/química , Glicina/análogos & derivados , Peroxidase/metabolismo , Cromatografia Líquida de Alta Pressão , Ensaios Enzimáticos , Inibidores Enzimáticos/farmacologia , Peroxidase de Eosinófilo/análise , Peroxidase de Eosinófilo/antagonistas & inibidores , Glicina/química , Halogenação , Humanos , Concentração de Íons de Hidrogênio , Cinética , Peroxidase/análise , Peroxidase/antagonistas & inibidoresRESUMO
BACKGROUND: Flaviviruses are a genre of closely related viral pathogens which emerged in the last decades in Brazil and in the world. Saint (St.) Louis encephalitis virus (SLEV) is a neglected flavivirus that can cause a severe neurological disease that may lead to death or sequelae. St. Louis encephalitis pathogenesis is poorly understood, which hinders the development of specific treatment or vaccine. METHODS: To address this problem, we developed a model of SLEV infection in mice to study mechanisms involved in the pathogenesis of severe disease. The model consists in the intracranial inoculation of the SLEV strain BeH 355964, a strain isolated from a symptomatic human patient in Brazil, in adult immunocompetent mice. RESULTS: Inoculated mice presented SLEV replication in the brain, accompanied by tissue damage, disease signs, and mortality approximately 7 days post infection. Infection was characterized by the production of proinflammatory cytokines and interferons and by leukocyte recruitment to the brain, composed mainly by neutrophils and lymphocytes. In vitro experiments indicated that SLEV is able to replicate in both neurons and glia and caused neuronal death and cytokine production, respectively. CONCLUSIONS: Altogether, intracranial SLEV infection leads to meningoencephalitis in mice, recapitulating several aspects of St. Louis encephalitis in humans. Our study indicates that the central nervous system (CNS) inflammation is a major component of SLEV-induced disease. This model may be useful to identify mechanisms of disease pathogenesis or resistance to SLEV infection.
Assuntos
Citocinas/metabolismo , Modelos Animais de Doenças , Vírus da Encefalite de St. Louis/fisiologia , Encefalite de St. Louis/patologia , Análise de Variância , Animais , Linhagem Celular Transformada , Encefalite de St. Louis/virologia , Peroxidase de Eosinófilo/metabolismo , Hexosaminidases/metabolismo , Leucócitos/metabolismo , Leucócitos/virologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Peroxidase/metabolismo , Fatores de Tempo , Carga ViralRESUMO
Prior investigations showed that increased levels of cyclic AMP down-regulate lung inflammatory changes, stimulating the interest in phosphodiesterase (PDE)4 as therapeutic target. Here, we described the synthesis, pharmacological profile and docking properties of a novel sulfonamide series (5 and 6a-k) designed as PDE4 inhibitors. Compounds were screened for their selectivity against the four isoforms of human PDE4 using an IMAP fluorescence polarized protocol. The effect on allergen- or LPS-induced lung inflammation and airway hyper-reactivity (AHR) was studied in A/J mice, while the xylazine/ketamine-induced anesthesia test was employed as a behavioral correlate of emesis in rodents. As compared to rolipram, the most promising screened compound, 6a (LASSBio-448) presented a better inhibitory index concerning PDE4D/PDE4A or PDE4D/PDE4B. Accordingly, docking analyses of the putative interactions of LASSBio-448 revealed similar poses in the active site of PDE4A and PDE4C, but slight unlike orientations in PDE4B and PDE4D. LASSBio-448 (100 mg/kg, oral), 1 h before provocation, inhibited allergen-induced eosinophil accumulation in BAL fluid and lung tissue samples. Under an interventional approach, LASSBio-448 reversed ongoing lung eosinophilic infiltration, mucus exacerbation, peribronchiolar fibrosis and AHR by allergen provocation, in a mechanism clearly associated with blockade of pro-inflammatory mediators such as IL-4, IL-5, IL-13 and eotaxin-2. LASSBio-448 (2.5 and 10 mg/kg) also prevented inflammation and AHR induced by LPS. Finally, the sulfonamide derivative was shown to be less pro-emetic than rolipram and cilomilast in the assay employed. These findings suggest that LASSBio-448 is a new PDE4 inhibitor with marked potential to prevent and reverse pivotal pathological features of diseases characterized by lung inflammation, such as asthma.
Assuntos
Inibidores da Fosfodiesterase 4/farmacologia , Sulfonamidas/farmacologia , Animais , Domínio Catalítico , AMP Cíclico/análise , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/efeitos dos fármacos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Peroxidase de Eosinófilo/metabolismo , Cobaias , Humanos , Inflamação/tratamento farmacológico , Pulmão/efeitos dos fármacos , Pulmão/enzimologia , Masculino , Camundongos , Simulação de Acoplamento Molecular/métodos , Contração Muscular/efeitos dos fármacos , Músculo Liso/química , Músculo Liso/efeitos dos fármacos , Peroxidase/metabolismo , Inibidores da Fosfodiesterase 4/síntese química , Isoformas de Proteínas/efeitos dos fármacos , Hipersensibilidade Respiratória/tratamento farmacológico , Sulfonamidas/síntese química , Traqueia/efeitos dos fármacosRESUMO
Identifying new target molecules through which eosinophils secrete their stored proteins may reveal new therapeutic approaches for the control of eosinophilic disorders such as host immune responses to parasites. We have recently reported the expression of the purinergic P2Y12 receptor (P2Y12R) in human eosinophils; however, its functional role in this cell type and its involvement in eosinophilic inflammation remain unknown. Here, we investigated functional roles of P2Y12R in isolated human eosinophils and in a murine model of eosinophilic inflammation induced by Schistosoma mansoni (S. mansoni) infection. We found that adenosine 5'-diphosphate (ADP) induced human eosinophils to secrete eosinophil peroxidase (EPO) in a P2Y12R dependent manner. However, ADP did not interfere with human eosinophil apoptosis or chemotaxis in vitro. In vivo, C57Bl/6 mice were infected with cercariae of the Belo Horizonte strain of S. mansoni. Analyses performed 55 days post infection revealed that P2Y12R blockade reduced the granulomatous hepatic area and the eosinophilic infiltrate, collagen deposition and IL-13/IL-4 production in the liver without affecting the parasite oviposition. As found for humans, murine eosinophils also express the P2Y12R. P2Y12R inhibition increased blood eosinophilia, whereas it decreased the bone marrow eosinophil count. Our results suggest that P2Y12R has an important role in eosinophil EPO secretion and in establishing the inflammatory response in the course of a S. mansoni infection.
Assuntos
Eosinófilos/metabolismo , Receptores Purinérgicos P2Y12/metabolismo , Schistosoma mansoni/patogenicidade , Difosfato de Adenosina/farmacologia , Animais , Células da Medula Óssea/citologia , Sobrevivência Celular/efeitos dos fármacos , Colágeno/metabolismo , Modelos Animais de Doenças , Peroxidase de Eosinófilo/metabolismo , Eosinófilos/efeitos dos fármacos , Eosinófilos/imunologia , Humanos , Inflamação , Interleucina-13/análise , Interleucina-13/sangue , Interleucina-4/análise , Interleucina-4/sangue , Fígado/metabolismo , Fígado/parasitologia , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Receptores Purinérgicos P2Y12/química , Receptores Purinérgicos P2Y12/genética , Esquistossomose mansoni/imunologia , Esquistossomose mansoni/parasitologia , Esquistossomose mansoni/patologia , Células Th2/imunologiaRESUMO
BACKGROUND: The prevalence of allergic diseases such as asthma has significantly increased worldwide, making it a public health concern. There is an urgent need for new anti-inflammatory agents with selective pharmacology and lower toxicity. Plant extracts have been used for centuries in traditional medicine to alleviate inflammatory diseases. In this work, we evaluated the anti-allergic activity of Cymbopogon citratus (Cy), a medicinal herb used by folk medicine to treat asthma. METHODS: We used a murine model of respiratory allergy to the mite Blomia tropicalis (Bt) and evaluated certain parameters known to be altered in this model. A/J mice were sensitized (100 µg/animal s.c.) and challenged (10 µg/animal i.n.) with Bt mite extract and treated with 60, 120 or 180 mg/kg of Cy standardized hexane extract. The parameters evaluated included: cellular infiltrate in bronchoalveolar lavage (BAL); eosinophil peroxidase activity (EPO); histopathological examination of the lung; serum levels of specific IgE, IgG1 and IgG2a; Th2 cytokine concentrations in BAL and expression of NF-κB. RESULTS: Our results showed that oral administration of a Cy hexane extract (especially 180 mg/Kg) reduced the numbers of leukocytes/eosinophils in BAL; the eosinophil peroxidase activity in BAL; the infiltration of leukocytes in lung tissue; the production of mucus in the respiratory tract; the level of IL-4 in BAL and the nuclear expression of NF-κB. CONCLUSIONS: The results presented demonstrate the potential of the Cy hexane extract to modulate allergic asthma; this extract may be an alternative future approach to treat this pathology.
Assuntos
Antialérgicos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Cymbopogon , Hipersensibilidade/tratamento farmacológico , Pulmão/efeitos dos fármacos , NF-kappa B/metabolismo , Fitoterapia , Alérgenos/imunologia , Animais , Antialérgicos/farmacologia , Anti-Inflamatórios/farmacologia , Asma/tratamento farmacológico , Asma/metabolismo , Líquido da Lavagem Broncoalveolar/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Peroxidase de Eosinófilo/metabolismo , Eosinófilos/metabolismo , Hipersensibilidade/metabolismo , Interleucina-4/imunologia , Leucócitos/metabolismo , Pulmão/metabolismo , Masculino , Camundongos , Ácaros , Muco/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Transdução de Sinais/efeitos dos fármacosRESUMO
The fish gill is in direct and standing contact with the immediate external environment and, therefore, is highly vulnerable to aquatic pollutants. In this study, Prochilodus argenteus were caught at two different points in São Francisco river. The first point is located near Três Marias dam, while the second is placed downstream the Abaeté river. Chemical approaches showed the presence of metals contamination in the first point. Thus, the main goal of this study was to investigate the possible toxic effects of these contaminants and the likely use of biomarkers on fish gills. Biometric data of length and weight of fish were obtained in order to calculate the condition factor as an organismal biomarker. The histological changes in gills and alterations in mucous and rodlet cells occurrence were detected microscopically and evaluated with quantitative analyses. Myeloperoxidase (MPO) and Eosinophil Peroxidase (EPO) were also assessed in fish gill. The analysis of the water and sediment samples revealed the presence of metals at the two points. As and Cd were detected at higher concentrations at point 1. The presence of lamellar cell hyperplasia, lamellar fusion, lamellar edema and inflammatory foci varied according to the point. Additionally, mucous and rodlet cells and MPO and EPO activities showed variability according to the environmental conditions. Furthermore, with exception of lamellar hyperplasia and eosinophil peroxidase activity, all others parameters showed sex-variation responses. At the first point, male fish showed a chronical inflammation in gills due to the lowest activity of MPO and EPO, as well as low occurrence of inflammatory foci and glycoprotein secretion by mucous cells, while female fish presented an opposite pattern of response to the same environmental conditions. Therefore, we suggest the use of such biomarkers in future monitoring of aquatic systems, taking into account the sex-variation responses.
Assuntos
Caraciformes/imunologia , Caraciformes/metabolismo , Brânquias/efeitos dos fármacos , Metais/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Brasil , Caraciformes/anatomia & histologia , Monitoramento Ambiental , Peroxidase de Eosinófilo/metabolismo , Feminino , Brânquias/enzimologia , Brânquias/imunologia , Brânquias/patologia , Masculino , Peroxidase/metabolismo , Rios/química , Fatores Sexuais , Espectrofotometria AtômicaRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: In Brazil, the plant Aloe saponaria Haw, popularly known as "babosa pintadinha", has been empirically used for its potential effect on thermal injury. Because there are no scientific data confirming its popular use, the aim of the present study was to investigate the effects of Aloe saponaria on nociceptive and inflammatory parameters in a rat model of thermal injury. MATERIALS AND METHODS: Adult male Wistar rats were subjected to a thermal injury or sham procedure (immersion in water at 70 or 37°C, respectively, for 5 or 8s). Burned animals were topically treated with vehicle (base cream), sulfadiazine 1% (positive control) or Aloe saponaria cream (0.3%-30%) once a day for 2 or 6 days. Each day, 30min before the treatment, we measured nociceptive (static and dynamic mechanical allodynia, thermal allodynia and spontaneous pain) and inflammatory (paw edema) parameters. Moreover, enzymatic indicators of leukocyte infiltration into burned tissue were also determined 2 or 6 days after the thermal injury. RESULTS: The thermal injury (fist and second-degree) procedure, but not the sham procedure, induced nociception and inflammation from 1 to 6 days after the injury. The topical treatment with Aloe saponaria cream (10%) reduced nociceptive behaviors from day 1 to 6 (peak at day 2), edema at days 5 and 6 (peak at day 6) and myeloperoxidase, N-acetyl-glucosaminidase and eosinoperoxidase activities at day 6. The antinociceptive and anti-inflammatory effects of Aloe saponaria were obtained with doses of 3%-30%, with maximal inhibition obtained with a dose of 10% (reductions of 39±9%, 41±9%, 31±7%, 83±7% and 23±2% for static and dynamic mechanical allodynia, thermal allodynia, spontaneous pain and paw edema, respectively). CONCLUSION: Our results demonstrate that topically applied Aloe saponaria presented antinociceptive and anti-inflammatory effects in rats subjected to a thermal injury, which supports its traditional use for burn injuries.
Assuntos
Aloe , Analgésicos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Queimaduras/tratamento farmacológico , Hiperalgesia/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Acetilglucosaminidase/metabolismo , Analgésicos/química , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Comportamento Animal/efeitos dos fármacos , Queimaduras/patologia , Queimaduras/fisiopatologia , Edema/tratamento farmacológico , Edema/patologia , Edema/fisiopatologia , Peroxidase de Eosinófilo/metabolismo , Flavonoides/isolamento & purificação , Temperatura Alta , Hiperalgesia/patologia , Hiperalgesia/fisiopatologia , Masculino , Peroxidase/metabolismo , Fenóis/isolamento & purificação , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta , Ratos , Ratos WistarRESUMO
OBJECTIVE: To determine whether a short-term protocol using subcutaneous sensitization with ovalbumin, without the use of adjuvants, would induce an eosinophilic response in the lungs of mice similar to that observed in previous, well-established protocols. METHODS: Adult female BALB/c mice were randomized and divided into groups according to the number of sensitizations with ovalbumin and the number/dosage of intranasal ovalbumin challenges. The short-term protocol (10 days) consisted of one sensitization with ovalbumin and three ovalbumin challenges (100 µg). Total and differential cell counts in BAL fluid, levels of eosinophil peroxidase in lung tissue, and histopathological examination of the lungs were performed 24 h after the last ovalbumin challenge. RESULTS: No significant differences were found among the groups regarding the variables studied. The short-term protocol, as well as the other protocols studied, induced an eosinophilic response similar to that obtained in the positive control. CONCLUSIONS: Subcutaneous sensitization with ovalbumin and without the use of adjuvants resulted in a significant allergic response in the lungs of mice, even in the short-term protocol group. Our findings suggest that this short-term protocol can be used as a first-line pre-clinical test for the study of new medications, reducing the costs and observation periods.
Assuntos
Asma/patologia , Hiper-Reatividade Brônquica/patologia , Peroxidase de Eosinófilo/metabolismo , Pulmão/patologia , Ovalbumina , Eosinofilia Pulmonar/imunologia , Doença Aguda , Animais , Asma/enzimologia , Hiper-Reatividade Brônquica/enzimologia , Testes de Provocação Brônquica , Líquido da Lavagem Broncoalveolar/citologia , Modelos Animais de Doenças , Feminino , Pulmão/enzimologia , Camundongos , Camundongos Endogâmicos BALB C , Eosinofilia Pulmonar/patologia , Distribuição AleatóriaRESUMO
OBJETIVO: Determinar se um protocolo curto de sensibilização com ovalbumina subcutânea, sem adjuvante, induziria uma resposta pulmonar eosinofílica em pulmões de camundongos similar àquela encontrada em protocolos previamente estabelecidos. MÉTODOS: Fêmeas adultas de camundongos BALB/c foram randomizadas e divididas em grupos de acordo com o número de sensibilizações com ovalbumina e o número/dosagem de provocação intranasal. O protocolo curto (10 dias) consistiu de uma sensibilização e três provocações com ovalbumina (100 µg). A contagem total e diferencial de células no lavado broncoalveolar, o nível de peroxidase eosinofílica no tecido pulmonar e o exame histopatológico dos pulmões foram realizados 24 h após a última provocação. RESULTADOS: Não houve diferenças significativas entre os grupos em relação às variáveis estudadas. O protocolo curto, assim como os outros protocolos estudados, induziu uma resposta eosinofílica pulmonar semelhante àquela do grupo controle positivo. CONCLUSÕES: A sensibilização por ovalbumina subcutânea sem o uso de adjuvante resultou em uma significativa resposta pulmonar alérgica em ratos, mesmo no grupo de protocolo curto. Nossos achados sugerem que esse protocolo curto pode ser utilizado como teste pré-clínico de primeira linha para a pesquisa de novos fármacos, reduzindo custos e o tempo de observação.
OBJECTIVE: To determine whether a short-term protocol using subcutaneous sensitization with ovalbumin, without the use of adjuvants, would induce an eosinophilic response in the lungs of mice similar to that observed in previous, well-established protocols. METHODS: Adult female BALB/c mice were randomized and divided into groups according to the number of sensitizations with ovalbumin and the number/dosage of intranasal ovalbumin challenges. The short-term protocol (10 days) consisted of one sensitization with ovalbumin and three ovalbumin challenges (100 µg). Total and differential cell counts in BAL fluid, levels of eosinophil peroxidase in lung tissue, and histopathological examination of the lungs were performed 24 h after the last ovalbumin challenge. RESULTS: No significant differences were found among the groups regarding the variables studied. The short-term protocol, as well as the other protocols studied, induced an eosinophilic response similar to that obtained in the positive control. CONCLUSIONS: Subcutaneous sensitization with ovalbumin and without the use of adjuvants resulted in a significant allergic response in the lungs of mice, even in the short-term protocol group. Our findings suggest that this short-term protocol can be used as a first-line pre-clinical test for the study of new medications, reducing the costs and observation periods.
Assuntos
Animais , Feminino , Camundongos , Asma/patologia , Hiper-Reatividade Brônquica/patologia , Peroxidase de Eosinófilo/metabolismo , Pulmão/patologia , Ovalbumina , Eosinofilia Pulmonar/imunologia , Doença Aguda , Asma/enzimologia , Testes de Provocação Brônquica , Hiper-Reatividade Brônquica/enzimologia , Líquido da Lavagem Broncoalveolar/citologia , Modelos Animais de Doenças , Pulmão/enzimologia , Camundongos Endogâmicos BALB C , Eosinofilia Pulmonar/patologia , Distribuição AleatóriaRESUMO
Allergic asthma has emerged as an important public health problem of urban populations in developed countries. Very often herbal medicine is used to treat this widespread disease, due to the lack of efficacy and the important side effects related to the classical drugs in use. Along this line, Ocimum gratissimum (Og) is a plant widely used in Brazilian folk medicine to treat inflammatory disorders, such as asthma. In the present study we evaluated the immunomodulatory effects of Og and rosmarinic acid (RA, a polyphenolic compound) in a murine model of respiratory allergy induced by the Blomia tropicalis (Bt) mite. The respiratory allergy was induced in A/J mice by administration of Bt extract and the treatment was done using 25, 50 or 100mg/kg of an Og methanolic extract or using 2, 20 or 200mg/kg of RA. We then evaluated the changes induced by these drugs on immunological parameters related to the allergic process, which are up-regulated in this allergic model. The treatment of animals with 100mg/Kg Og and 200mg/Kg RA led to a significant reduction in the numbers of leukocytes/eosinophils in bronchoalveolar lavage (BAL); eosinophil peroxidase activity in BAL; presence of mucus in respiratory tract, histopathological changes in the lung, and IL-4 in BAL. These results suggest that the methanolic extract of Og and the polyphenol RA have therapeutic potential in this murine model of respiratory allergy to a clinically relevant human sensitizer allergen.
Assuntos
Cinamatos/uso terapêutico , Depsídeos/uso terapêutico , Eosinófilos/imunologia , Fatores Imunológicos/uso terapêutico , Ocimum/química , Extratos Vegetais/uso terapêutico , Hipersensibilidade Respiratória/tratamento farmacológico , Sarcoptidae/imunologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Cinamatos/administração & dosagem , Cinamatos/isolamento & purificação , Depsídeos/administração & dosagem , Depsídeos/isolamento & purificação , Modelos Animais de Doenças , Peroxidase de Eosinófilo/metabolismo , Eosinófilos/efeitos dos fármacos , Eosinófilos/enzimologia , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/isolamento & purificação , Interleucina-4/imunologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Hipersensibilidade Respiratória/imunologia , Hipersensibilidade Respiratória/patologia , Mucosa Respiratória/imunologia , Ácido RosmarínicoRESUMO
BACKGROUND: Asthma is a disease characterized by intermittent obstruction of the airways and chronic inflammation that affects approximately 300 million people worldwide. The immune response in asthma is predominantly T(H)2, with high levels of total and allergen-specific IgE and bronchial eosinophilia. Asthma treatment is aimed at controlling the disease, and the drugs used currently have systemic adverse effects and generally are not effective in difficult-to-control cases. OBJECTIVE: To investigate the effect of aqueous extract of Echinodorus grandiflorus, a plant used in folk medicine for its diuretic and anti-inflammatory properties, in a model of pulmonary allergy. METHODS: BALB/c mice were intraperitoneally sensitized and nasally challenged with ovalbumin. Aqueous extract and dexamethasone treatments (0.1 mL/d per mouse) were initiated on day 32 and concluded on day 40. Eight hours after the last challenge evaluations, of serum, bronchoalveolar lavage, and lung tissue were performed. RESULTS: Oral treatment with the extract markedly reduced the number of total cells and eosinophils in bronchoalveolar lavage. The eosinophil peroxidase activity in lung tissue, the levels of ovalbumin-specific IgE in serum, the levels of CCL11, and the gene expression of interleukin 4 and interleukin 13 in lung tissue were also lower after treatment. CONCLUSIONS: These results suggest that the aqueous extract of E grandiflorus is able to modulate allergic pulmonary inflammation and may be useful as a potential therapeutic agent for asthma.
Assuntos
Alismataceae , Asma/tratamento farmacológico , Pneumopatias/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Hipersensibilidade Respiratória/tratamento farmacológico , Animais , Asma/imunologia , Líquido da Lavagem Broncoalveolar/imunologia , Quimiocina CCL11/metabolismo , Dexametasona/administração & dosagem , Dexametasona/uso terapêutico , Modelos Animais de Doenças , Peroxidase de Eosinófilo/metabolismo , Imunoglobulina E/sangue , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Pulmão/imunologia , Medicina Tradicional , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Hipersensibilidade Respiratória/imunologia , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Asthma is one of the most prevalent chronic diseases worldwide. Medicinal plants are historically used in its treatment. The plant Cissampelos sympodialis, known in Northeastern Brazil as "Jarrinha" or "Milona", is used to treat some inflammatory conditions, including asthma. The objective of this study was to evaluate the potential of Cissampelos sympodialis EICHL. extract (CsE) and its isolated alkaloids, especially warifteine (Wa) on a Blomia tropicalis extract (BtE)-induced experimental model of allergy. The respiratory allergy was induced in AJ mice by the administration of BtE. Mice were orally treated with the 400 mg/kg of CsE or 8 mg/kg of total alkaloids fraction (TAF) or 4 mg/kg of Wa and the following parameters were analyzed: (a) total cell numbers in bronchoalveolar fluid (BAF); (b) differential cell numbers in BAF; (c) eosinophil peroxidase (EPO) activity in BAF; (d) IgE serum levels by passive cutaneous anaphylaxis; (e) IL-5, IL-13, IL-10, and IFN-γ levels in BAF; (f) histopathological alterations in the lung. The treatment of the animals with CsE, Wa or TAF led to a reduction in the numbers of total cells and eosinophils in BAF. The same reduction was observed in EPO levels in the BAF. The levels of IL-5 and IL-13 were also reduced in animals treated with Cissampelos sympodialis, while IL-10 levels were significantly increased in the BAF of CsE-treated animals. The treatment also decreased the density of inflammatory cells in the lung by histopathological examination demonstrating the potential of this medicinal plant as new agent for asthma treatment.
Assuntos
Alcaloides/farmacologia , Asma/tratamento farmacológico , Asma/imunologia , Cissampelos/química , Ácaros/imunologia , Alcaloides/isolamento & purificação , Animais , Asma/metabolismo , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Citocinas/imunologia , Citocinas/metabolismo , Peroxidase de Eosinófilo/metabolismo , Feminino , Imunoglobulina E/imunologia , Imunoglobulina E/metabolismo , Camundongos , Camundongos Endogâmicos A , Modelos Teóricos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Ratos , Ratos WistarRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: The bee pollen is used in folk medicine to alleviate allergic reactions. The bee pollen phenolic extract (BPPE) consists in phenolic compounds (flavonoids) from plants picked by Apis mellifera bee. AIM OF THIS STUDY: Here we evaluated the anti-allergic property of the BPPE and the flavonoid myricetin (MYR) in murine model of ovalbumin (OVA)-induced allergy. MATERIALS AND METHODS: The study focused on the BPPE or myricetin treatment of OVA-sensitized BALB/c mice and their effects on the IgE and IgG1 production, pulmonary cell migration, eosinophil peroxidase (EPO) activity and anaphylactic shock reaction. RESULTS: The BPPE treatment (200mg/kg) showed inhibition of the paw edema, IgE and IgG(1) OVA-specific production, leukocyte migration to the bronchoalveolar lavage (BAL) and EPO activity in lungs. In addition, BPPE treatment showed partial protection on the anaphylactic shock reaction induced by OVA. Treatment with myricetin (5 mg/kg) also inhibited pulmonary cell migration and IgE and IgG(1) OVA-specific production. CONCLUSIONS: These results support the hypothesis the myricetin is one of the flavonoids of BPPE responsible for the anti-allergic effect and a potential tool to treat allergies.
Assuntos
Antialérgicos/farmacologia , Flavonoides/farmacologia , Extratos Vegetais/farmacologia , Pólen/química , Anafilaxia/tratamento farmacológico , Anafilaxia/imunologia , Animais , Antialérgicos/isolamento & purificação , Abelhas , Líquido da Lavagem Broncoalveolar/imunologia , Movimento Celular/imunologia , Modelos Animais de Doenças , Peroxidase de Eosinófilo/efeitos dos fármacos , Peroxidase de Eosinófilo/metabolismo , Feminino , Flavonoides/isolamento & purificação , Imunoglobulina E/efeitos dos fármacos , Imunoglobulina E/imunologia , Imunoglobulina G/efeitos dos fármacos , Imunoglobulina G/imunologia , Leucócitos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Ratos , Ratos WistarRESUMO
BACKGROUND: Eosinophils have been identified in tissues from patients with Crohn's disease (CD) and ulcerative colitis (UC) but whether they contribute to IBD pathogenesis is unknown. This study aimed to investigate the functional activity and morphological aspects of peripheral-blood eosinophils from IBD patients compared to those from healthy volunteers (HVs). METHODS: Eosinophils from HVs and CD and UC patients were purified using a Percoll gradient and then a immunomagnetic cell separator. Functional activity in inactivated and previously activated cells was investigated by measuring adhesion to fibronectin and chemotaxis to fMLP, and degranulation was measured by release of eosinophil peroxidase (EPO). Cell morphology was investigated using electron microscopy. RESULTS: Eosinophil adhesion to human fibronectin in both inactivated and PAF-stimulated and PMA-stimulated eosinophils was markedly higher in patients with CD than in either patients with UC or HVs. Similarly, the chemotactic response was markedly higher in eosinophils isolated from CD patients than in those isolated from UC patients or HVs. Baseline EPO release was higher in eosinophils isolated from UC patients than in those isolated from HVs or CD patients. Stimulation with fMLP or PMA did not further increase EPO release in cells from UC or CD patients. Comparable expression of MAC- 1 and VLA-4 adhesion molecules was observed on the surfaces of eosinophils from all groups, and an greater number of granules was noted in the eosinophils from UC patients than in those from CD patients. CONCLUSIONS: Our results indicate that peripheral-blood eosinophils are potentially primed and activated in IBD patients. Whether the differences in the morphology and functional responses of eosinophil from UC and CD patients reflect differences in disease phenotype remains to be elucidated.
Assuntos
Adesão Celular , Degranulação Celular , Quimiotaxia , Colite Ulcerativa/fisiopatologia , Doença de Crohn/fisiopatologia , Eosinófilos/fisiologia , Colite Ulcerativa/patologia , Doença de Crohn/patologia , Peroxidase de Eosinófilo/metabolismo , Eosinófilos/patologia , Feminino , Fibronectinas , Humanos , Fatores Imunológicos/metabolismo , Técnicas In Vitro , Integrina alfa4beta1/metabolismo , Antígeno de Macrófago 1/metabolismo , Masculino , Microscopia EletrônicaRESUMO
BACKGROUND: Eosinophils contribute to the early features of allergic lung inflammation through the generation and release of a plethora of mediators. Eosinophil peroxidase (EPO) is one of the eosinophil granule proteins involved in the early response, but its participation in airway remodeling is not established. The present study addressed this question comparing an EPO-deficient mouse strain (NZW) with BALB/c and C57Bl/c strains. METHODS: Mice were immunized with ovalbumin/alum, challenged twice with ovalbumin aerosol, and lung responses were measured at day 22 or 28. Collagen, mucus and eosinophils were determined in lung sections stained with picrosirius, periodic acid-Schiff or hematoxylin-eosin; transforming growth factor-beta and vascular endothelial growth factor were determined by ELISA, lipid bodies by enumeration in osmium-stained eosinophils, and airway reactivity to methacholine in isolated lung preparations. RESULTS: NZW mice showed significantly less collagen around bronchi and blood vessels, less mucus and less eosinophils around bronchi. Eosinophil lipid body formation and airway hyperreactivity were comparable among strains. Levels of transforming growth factor-beta were also comparable; however, the NZW mice showed much higher levels of vascular endothelial growth factor, even under basal conditions. CONCLUSIONS: In allergic lung inflammation, the combination of EPO deficiency and overexpression of VEGF found in NZW mice is associated with less collagen deposition, less mucus and reduced tissue eosinophilia. Eosinophil activation and airway hyperreactivity in NZW mice were similar to the other strains.
Assuntos
Asma/imunologia , Colágeno/imunologia , Peroxidase de Eosinófilo/metabolismo , Fator A de Crescimento do Endotélio Vascular/imunologia , Animais , Asma/induzido quimicamente , Asma/fisiopatologia , Brônquios/efeitos dos fármacos , Brônquios/patologia , Brônquios/fisiopatologia , Hiper-Reatividade Brônquica , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Peroxidase de Eosinófilo/deficiência , Peroxidase de Eosinófilo/genética , Eosinofilia , Masculino , Cloreto de Metacolina/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ovalbumina , Fator de Crescimento Transformador beta/imunologiaRESUMO
The inflammatory and functional changes that occur in murine lung after infection with 2500 infective Ascaris suum eggs were studied in this work. A sequential influx of neutrophils, mononuclear cells and eosinophils occurred into airways concomitantly with migration of larvae from liver to the lungs. Histological analysis of the lung showed a severe intra-alveolar haemorrhage at the peak of larval migration (day 8) and the most intense inflammatory cell infiltrate on day 14. Ascaris L3 were found in alveolar spaces and inside bronchioles on day 8. The number of eosinophils was elevated in the blood on days 8 and 14. The peak of eosinophil influx into the lung was at day 14, as indicated by the high levels of eosinophil peroxidase activity, followed by their migration into the airways. The antibody response against egg and larval antigens consisted mainly of IgG1 and IgM, and also of IgE and anaphylactic IgG1, that cross-reacted with adult worm antigens. Total IgE levels were substantially elevated during the infection. Measurement of lung mechanical parameters showed airway hyperreactivity in infected mice. In conclusion, the murine model of A. suum infection mimics the Th2-induced parameters observed in pigs and humans and can be used to analyse the immunoregulatory properties of this helminth.