RESUMO
Mast cells (MCs) are main effector cells in allergic inflammation and after activation, they release stored (histamine, heparin, proteases) and newly synthesized (lipid mediators and cytokines) substances. In the gastrointestinal tract the largest MC population is located in the lamina propria and submucosa whereas several signals such as the cytokine IL-4, seem to increase the granule content and to stimulate a remarkable expansion of intestinal MCs. The broad range of MC-derived bioactive molecules may explain their involvement in many different allergic disorders of the gastrointestinal tract. Annexin A1 (AnxA1) is a 37 KDa glucocorticoid induced monomeric protein selectively distributed in certain tissues. Its activity can be reproduced by mimetic peptides of the N-terminal portion, such as Ac2-26, that share the same receptor FPR-L1. Although previous reports demonstrated that AnxA1 inhibits MC degranulation in murine models, the effects of exogenous peptide Ac2-26 on intestinal MCs or the biological functions of the Ac2-26/FPR2 system in human MCs have been poorly studied. To determine the effects of Ac2-26 on the function of MCs toward the possibility of AnxA1-based therapeutics, we treated WT and IL-4 knockout mice with peptide Ac2-26, and we examined the spontaneous and compound 48/80 stimulated colonic MC degranulation and cytokine production. Moreover, in vitro, using human mast cell line HMC-1 we demonstrated that exogenous AnxA1 peptide is capable of interfering with the HMC-1 degranulation in a direct pathway through formyl peptide receptors (FPRs). We envisage that our results can provide therapeutic strategies to reduce the release of MC mediators in inflammatory allergic processes.
Assuntos
Anexina A1/farmacologia , Degranulação Celular/efeitos dos fármacos , Colo/efeitos dos fármacos , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Mastócitos/efeitos dos fármacos , Peptídeos/farmacologia , Animais , Linhagem Celular , Colo/imunologia , Colo/metabolismo , Humanos , Interleucina-4/genética , Interleucina-4/metabolismo , Masculino , Mastócitos/imunologia , Mastócitos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Formil Peptídeo/metabolismo , Técnicas de Cultura de TecidosRESUMO
In this work, cashew apple pectin (CP) of the species Anacardium occidentale L. was used as an encapsulation matrix for hydrophobic drugs. The model drug chosen was mangiferin (Mf), a glycosylated C-xanthone which has antioxidant properties but low solubility in aqueous medium. CP (1-100 µg mL-1) was not toxic to human neutrophils and also did not significantly interfere with the pro-inflammatory mechanism of these cells in the concentration range of 12.5 and 100 µg mL-1. The results are promising because they show that pectin encapsulated mangiferin after spray drying presented an efficiency of 82.02%. The results obtained in the dissolution test, simulating the release of mangiferin in the gastrointestinal tract (pH 1.2, 4.6 and 6.8) and using Franz diffusion cells (pH 7.4), showed that cashew pectin may be a promising vehicle in prolonged drug delivery systems for both oral and dermal applications.
Assuntos
Anacardium/química , Portadores de Fármacos/administração & dosagem , Composição de Medicamentos/métodos , Neutrófilos/efeitos dos fármacos , Pectinas/administração & dosagem , Secagem por Atomização , Xantonas/administração & dosagem , Cápsulas , Degranulação Celular/efeitos dos fármacos , Células Cultivadas , Técnicas de Química Analítica , Preparações de Ação Retardada , Difusão , Liberação Controlada de Fármacos , Frutas/química , Humanos , Microscopia Eletrônica de Varredura , Pectinas/isolamento & purificação , Peroxidase/análise , Solubilidade , ViscosidadeRESUMO
Existing evidence suggests that the local anaesthetic mexiletine can be beneficial for patients with asthma. However, caution is required since anaesthesia of the airways inhibits protective bronchodilator neuronal reflexes, limiting applications in conditions of hyperirritable airways. Here, we describe the synthesis of a new series of mexiletine analogues, which were screened for reduced activity in Na+ channels and improved smooth muscle relaxant effects, that were evaluated using the patch-clamp technique and an isolated tracheal organ bath, respectively. JME-173 (1-(4-bromo-3,5-dimethylphenoxy)propan-2-amine) was the most effective among the four mexiletine analogues investigated. JME-173 was then studied in vivo using a murine model of lung inflammation induced by cigarette smoke (CS) and in vitro using neutrophil chemotaxis and mast cell degranulation assays. Finally, the JME-173 pharmacokinetic profile was assessed using HPLC-MS/MS bioanalytical method. JME-173 directly inhibited IL-8 (CXCL8)- and FMLP-induced human neutrophil chemotaxis and allergen-induced mast cell degranulation. After oral administration 1 h before CS exposure, JME-173 (50 mg/kg) strongly reduced the increased number of macrophages and neutrophils recovered in the bronchoalveolar effluent without altering lymphocyte counts. Pharmacokinetic experiments of JME-173 (10 mg/kg, orally) showed values of maximum concentration (Cmax), maximum time (Tmax), area under the blood concentration-time curve (AUC0-t) and area under the blood concentration-time curve from 0-Inf (AUC0-inf) of 163.3 ± 38.3 ng/mL, 1.2 ± 0.3 h, 729.4 ± 118.3 ng*h/ml and 868.9 ± 117.1 ng*h/ml (means ± S.E.M.), respectively. Collectively, these findings suggest that JME-173 has the potential to be an effective oral treatment for diseases associated with bronchoconstriction and inflammation.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Mexiletina/análogos & derivados , Mexiletina/farmacologia , Parassimpatolíticos/farmacologia , Bloqueadores dos Canais de Sódio/farmacologia , Canais de Sódio/efeitos dos fármacos , Animais , Área Sob a Curva , Líquido da Lavagem Broncoalveolar/citologia , Degranulação Celular/efeitos dos fármacos , Humanos , Masculino , Mastócitos/efeitos dos fármacos , Camundongos , Infiltração de Neutrófilos/efeitos dos fármacos , Técnicas de Patch-Clamp , Pneumonia/induzido quimicamente , Pneumonia/tratamento farmacológico , Ratos , Ratos Wistar , Fumaça , Relação Estrutura-Atividade , Produtos do TabacoRESUMO
Mast cell activation through the high-affinity IgE receptor (FcεRI) plays a central role in allergic reactions. FcεRI-mediated activation triggers multiple signaling pathways leading to degranulation and synthesis of different inflammatory mediators. IgE-mediated mast cell activation can be modulated by different molecules, including several drugs. Herein, we investigated the immunomodulatory activity of the histone deacetylase inhibitor valproic acid (VPA) on IgE-mediated mast cell activation. To this end, bone marrow-derived mast cells (BMMC) were sensitized with IgE and treated with VPA followed by FcεRI cross-linking. The results indicated that VPA reduced mast cell IgE-dependent degranulation and cytokine release. VPA also induced a significant reduction in the cell surface expression of FcεRI and CD117, but not other mast cell surface molecules. Interestingly, VPA treatment inhibited the phosphorylation of PLCγ2, a key signaling molecule involved in IgE-mediated degranulation and cytokine secretion. However, VPA did not affect the phosphorylation of other key components of the FcεRI signaling pathway, such as Syk, Akt, ERK1/2, or p38. Altogether, our data demonstrate that VPA affects PLCγ2 phosphorylation, which in turn decreases IgE-mediated mast cell activation. These results suggest that VPA might be a key modulator of allergic reactions and might be a promising therapeutic candidate.
Assuntos
Inibidores de Histona Desacetilases/farmacologia , Imunoglobulina E/imunologia , Mastócitos/efeitos dos fármacos , Fosfolipase C gama/antagonistas & inibidores , Receptores de IgE/efeitos dos fármacos , Ácido Valproico/farmacologia , Animais , Degranulação Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Interleucina-13/metabolismo , Interleucina-6/metabolismo , Mastócitos/citologia , Camundongos , Fosfolipase C gama/fisiologia , Receptores de IgE/biossíntese , Receptores de IgE/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Mast cells are connective tissue resident cells with morphological and functional characteristics that contribute to their role in allergic and inflammatory processes, host defense and maintenance of tissue homeostasis. Mast cell activation results in the release of pro-inflammatory mediators which are largely responsible for the physiological functions of mast cells. The lectin ArtinM, extracted from Artocarpus heterophyllus (jackfruit), binds to D-manose, thus inducing degranulation of mast cells. ArtinM has several immunomodulatory properties including acceleration of wound healing, and induction of cytokine release. The aim of the present study was to investigate the role of ArtinM in the activation and proliferation of mast cells. The rat mast cell line RBL-2H3 was used throughout this study. At a low concentration (0.25µg/mL), ArtinM induced mast cell activation and the release of IL-6 without stimulating the release of pre-formed or newly formed mediators. Additionally, when the cells were activated by ArtinM protein tyrosine phosphorylation was stimulated. The low concentration of ArtinM also activated the transcription factor NFkB, but not NFAT. ArtinM also affected the cell cycle and stimulated cell proliferation. Therefore, ArtinM may have therapeutic applications by modulating immune responses due to its ability to activate mast cells and promote the release of newly synthesized mediators. Additionally, ArtinM could have beneficial effects at low concentrations without degranulating mast cells and inducing allergic reactions.
Assuntos
Degranulação Celular/efeitos dos fármacos , Lectinas/farmacologia , Proteínas de Plantas/farmacologia , Animais , Artocarpus/metabolismo , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Proliferação de Células/efeitos dos fármacos , Interleucina-6/metabolismo , Mastócitos/citologia , Mastócitos/metabolismo , Mitose/efeitos dos fármacos , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , RatosRESUMO
Glycosylated flavonoids, caffeoylquinic acid and 3,5-dicaffeoylquinic acid have been identified in the ethyl acetate partition from the crude ethanol extract of Tocoyena bullata (Rubiaceae) leaves. The fraction containing the mixture of flavonol rutin and a tetraglycosylated flavonoid showed 89.2% inhibition and the mixture of isoquercitrin and 3,5-dicaffeoylquinic acid showed 88.5% inhibition of mast cell degranulation. These results demonstrated that the tetraglycosylated flavonoid, rutin, isoquercitrin and 3,5-dicaffeioylquinic acid were the most promising phenolics for inhibition of mast cell degranulation. For the first time the identification of phenolic constituents and their correlation with inhibitory effect on mast cell degranulation were reported in this work.
Assuntos
Degranulação Celular/efeitos dos fármacos , Mastócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Rubiaceae/química , Animais , Ácido Clorogênico/análogos & derivados , Ácido Clorogênico/farmacologia , Feminino , Flavonoides/química , Flavonoides/farmacologia , Flavonóis/química , Flavonóis/farmacologia , Mastócitos/fisiologia , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/química , Folhas de Planta/efeitos dos fármacos , Quercetina/análogos & derivados , Quercetina/farmacologia , Ratos Wistar , Rutina/farmacologia , Solventes/químicaRESUMO
Bauhinia forficata is a medicinal plant that has flavonoid components with hypoglycemic, antioxidant, hepatoprotective, antibacterial, antiviral and anti-inflammatory action. Aim of this study is to evaluate the action of B. forficata alcoholic extract in the male genital system of adult male Wistar rats. For that, 20 adult male Wistar rats were distributed into two experimental groups: the B. forficata group, receiving B. forficata alcoholic extract (0.1 ml/10 g body weight/day) on alternate days, and the control group, receiving just the vehicle for 30 days straight both via gavage. On the 31st day, the animals were euthanized, and the testis and epididymis were collected for histopathological, biochemical, morphometric, and sperm count analysis. Mass spectrometry identified new compounds in the extract: trans-caffeic acid, liquiritigenin, gallocatechin, and 2,4,6-trihydroxyphenanthren-2-glycoside. Biochemical analysis showed higher total cholesterol levels in the testis and lower malondialdehyde levels in the testis and epididymis, in the B. forficata group. The mast cell count showed a reduction in degranulated mast cells in the caput region of the epididymis, in the B. forficata group. The luminal compartment of the caput and the epithelial of the epididymis cauda were reduced, whereas the stromal region of the epididymis caput was increased in the B. forficata group, compared with the control group. The testicular tissue was less impaired, considering that all the histological analyses were similar to the control. We believe that B. forficata alcoholic extract in the male genital system showed antioxidant action, especially in the epididymal tissue.
Assuntos
Antioxidantes/farmacologia , Bauhinia/química , Epididimo/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Testículo/metabolismo , Animais , Degranulação Celular/efeitos dos fármacos , Colesterol/análise , Masculino , Malondialdeído/análise , Mastócitos/citologia , Fitoterapia , Ratos , Ratos WistarRESUMO
PURPOSE: The effect of a prophylactic oleuropein-rich diet before anesthesia accompanied by the widely-used steroid-based neuromuscular drug rocuronium on mast cell activation was investigated in the study. METHODS: 14 rabbits used in the study. The rabbits in the oleuropein group were given oleuropein-rich extract added to the animals' water at doses of 20 mg/kg oleuropein for 15 days orally. After 15 days, all rabbits in the two groups were given general anesthesia with rocuronium of 1 mg/kg. After 1 day, animals were sacrificed and the liver tissue sections stained with H&E, toluidine blue and tryptase for immunohistochemical study. RESULTS: There was no statistically significant difference between ALT, AST and albumin averages of the oleuropein and control groups (p> 0.05). The tryptase average of the control group was higher than the tryptase average of the oleuropein group and this difference was statistically significant (p=0.003). The T. blue average in the oleuropein group was higher than the control group. However, there was no statistically significant difference between groups (p=0.482). CONCLUSIONS: Rocuronium adverse effects, like hypersensitivity and anaphylaxis, may limit routine use of this substance. The use of oleuropein reduced the number of inflammatory cells and prevented degranulation.
Assuntos
Anestesia Geral/efeitos adversos , Anti-Inflamatórios/administração & dosagem , Iridoides/administração & dosagem , Mastócitos/efeitos dos fármacos , Fármacos Neuromusculares não Despolarizantes/efeitos adversos , Rocurônio/efeitos adversos , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Agregação Celular/efeitos dos fármacos , Degranulação Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Dietoterapia/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Imuno-Histoquímica , Glucosídeos Iridoides , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Mastócitos/patologia , Profilaxia Pré-Exposição/métodos , Coelhos , Distribuição Aleatória , Reprodutibilidade dos Testes , Albumina Sérica/análiseRESUMO
Abstract Purpose: The effect of a prophylactic oleuropein-rich diet before anesthesia accompanied by the widely-used steroid-based neuromuscular drug rocuronium on mast cell activation was investigated in the study. Methods: 14 rabbits used in the study. The rabbits in the oleuropein group were given oleuropein-rich extract added to the animals' water at doses of 20 mg/kg oleuropein for 15 days orally. After 15 days, all rabbits in the two groups were given general anesthesia with rocuronium of 1 mg/kg. After 1 day, animals were sacrificed and the liver tissue sections stained with H&E, toluidine blue and tryptase for immunohistochemical study. Results: There was no statistically significant difference between ALT, AST and albumin averages of the oleuropein and control groups (p> 0.05). The tryptase average of the control group was higher than the tryptase average of the oleuropein group and this difference was statistically significant (p=0.003). The T. blue average in the oleuropein group was higher than the control group. However, there was no statistically significant difference between groups (p=0.482). Conclusions: Rocuronium adverse effects, like hypersensitivity and anaphylaxis, may limit routine use of this substance. The use of oleuropein reduced the number of inflammatory cells and prevented degranulation.
Assuntos
Animais , Masculino , Coelhos , Fármacos Neuromusculares não Despolarizantes/efeitos adversos , Iridoides/administração & dosagem , Rocurônio/efeitos adversos , Anestesia Geral/efeitos adversos , Mastócitos/efeitos dos fármacos , Anti-Inflamatórios/administração & dosagem , Aspartato Aminotransferases/sangue , Albumina Sérica/análise , Distribuição Aleatória , Degranulação Celular/efeitos dos fármacos , Agregação Celular/efeitos dos fármacos , Reprodutibilidade dos Testes , Cromatografia Líquida de Alta Pressão , Dietoterapia/métodos , Alanina Transaminase/sangue , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Profilaxia Pré-Exposição/métodos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Mastócitos/patologiaRESUMO
Neuroinflammation is a recognized pathogenic mechanism underlying motor neuron degeneration in amyotrophic lateral sclerosis (ALS), but the inflammatory mechanisms influencing peripheral motor axon degeneration remain largely unknown. A recent report showed a pathogenic role for c-Kit-expressing mast cells mediating inflammation and neuromuscular junction denervation in muscles from SOD1G93A rats. Here, we have explored whether mast cells infiltrate skeletal muscles in autopsied muscles from ALS patients. We report that degranulating mast cells were abundant in the quadriceps muscles from ALS subjects but not in controls. Mast cells were associated with myofibers and motor endplates and, remarkably, interacted with neutrophils forming large extracellular traps. Mast cells and neutrophils were also abundant around motor axons in the extensor digitorum longus muscle, sciatic nerve, and ventral roots of symptomatic SOD1G93A rats, indicating that immune cell infiltration extends along the entire peripheral motor pathway. Postparalysis treatment of SOD1G93A rats with the tyrosine kinase inhibitor drug masitinib prevented mast cell and neutrophil infiltration, axonal pathology, secondary demyelination, and the loss of type 2B myofibers, compared with vehicle-treated rats. These findings provide further evidence for a yet unrecognized contribution of immune cells in peripheral motor pathway degeneration that can be therapeutically targeted by tyrosine kinase inhibitors.