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1.
Cancer Immunol Res ; 7(2): 321-334, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30610060

RESUMO

Macrophage-mediated cytotoxicity is controlled by surface receptor expression and activation. Despite the numerous studies documenting the role of macrophage C-type lectin receptors (CLR) in pathogen elimination, little is known about their contribution to antitumor responses. Here, we report that IL13 inhibits T-cell lymphoma and ovarian adenocarcinoma development in tumor-bearing mice through the conversion of tumor-supporting macrophages to cytotoxic effectors, characterized by a CLR signature composed of dectin-1 and mannose receptor (MR). We show that dectin-1 and MR are critical for the recognition of tumor cells through sialic acid-specific glycan structure on their surface and for the subsequent activation of macrophage tumoricidal response. Finally, we validated that IL13 antitumor effect mediated by dectin-1 and MR overexpression on macrophages can extend to various types of human tumors. Therefore, these results identify these CLRs as potential targets to promote macrophage antitumor response and represent an attractive approach to elicit tumor-associated macrophage tumoricidal properties.

2.
Electrophoresis ; 2018 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-30073670

RESUMO

Lipids are naturally occurring organic compounds that can be classified into a number of types based on their solubility in nonpolar organic solvents, and are generally insoluble in water. The great structural variety of these various types of lipids has led them to be components of many different biological substances such as oils, waxes, cellular membranes, tissues and biological fluids. The use of capillary electrophoresis (CE) for the study of lipids during the past 30 years has been relatively rare when compared to its use for other classes of biomolecules, primarily due to their insolubility in water. However, a number of interesting studies have been conducted, and as part of this review, we will present the different approaches that were used, which mainly consist of micellar kinetic chromatography and non-aqueous CE. The main advantages of the use of these techniques compared to GC is the very simple sample preparation that is required and, compared to LC, the very robust and quick separations that can be obtained. In this review, we present the various methods that have been reported in the literature that have been used for the study of fatty acids, phospholipids, glycerides, eicosanoids and sterols, with the inclusion of various tables presenting descriptions of the CE methods used as well as the methods of detection, including UV absorbance, fluorescence, mass spectrometry, and conductivity. This review aims to demonstrate that CE can be easily used for the analysis of lipids.

3.
Sci Rep ; 8(1): 12170, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30111876

RESUMO

Inhibition of regeneration and induction of tissue fibrosis are classic outcomes of tissue repair in adult mammals. Here, using a newly developed model of regeneration in adult mammals i.e. regeneration after massive resection of an inguinal fat pad, we demonstrate that both endogenous and exogenous opioids prevent tissue regeneration in adults, by inhibiting the early production of reactive oxygen species (ROS) that generally occurs after lesion and is required for regeneration. These effects can be overcome and regeneration induced by the use of an opioid antagonist. The results obtained in both our new model and the gold standard adult zebrafish demonstrate that this mechanism can be considered as a general paradigm in vertebrates. This work clearly demonstrates that ROS is required for tissue regeneration in adult mammals and shows the deleterious effect of opioids on tissue regeneration through the control of this ROS production. It thus raises questions about opioid-based analgesia in perioperative care.

4.
J Control Release ; 270: 120-134, 2018 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-29203413

RESUMO

Therapeutic strategies using drugs which cause Lysosomal Cell Death have been proposed for eradication of resistant cancer cells. In this context, nanotherapy based on Magnetic Intra-Lysosomal Hyperthermia (MILH) generated by magnetic nanoparticles (MNPs) that are grafted with ligands of receptors overexpressed in tumors appears to be a very promising therapeutic option. However, mechanisms whereby MILH induces cell death are still elusive. Herein, using Gastrin-grafted MNPs specifically delivered to lysosomes of tumor cells from different cancers, we provide evidences that MILH causes cell death through a non-apoptotic signaling pathway. The mechanism of cell death involves a local temperature elevation at the nanoparticle periphery which enhances the production of reactive oxygen species through the lysosomal Fenton reaction. Subsequently, MILH induces lipid peroxidation, lysosomal membrane permeabilization and leakage of lysosomal enzymes into the cytosol, including Cathepsin-B which activates Caspase-1 but not apoptotic Caspase-3. These data highlight the clear potential of MILH for the eradication of tumors overexpressing receptors.

5.
Front Immunol ; 8: 1650, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29250064

RESUMO

Despite the growing knowledge with regard to the immunomodulatory properties of host defense peptides, their impact on macrophage differentiation and on its associated microbicidal functions is still poorly understood. Here, we demonstrated that the P17, a new cationic antimicrobial peptide from ant venom, induces an alternative phenotype of human monocyte-derived macrophages (h-MDMs). This phenotype is characterized by a C-type lectin receptors (CLRs) signature composed of mannose receptor (MR) and Dectin-1 expression. Concomitantly, this activation is associated to an inflammatory profile characterized by reactive oxygen species (ROS), interleukin (IL)-1ß, and TNF-α release. P17-activated h-MDMs exhibit an improved capacity to recognize and to engulf Candida albicans through the overexpression both of MR and Dectin-1. This upregulation requires arachidonic acid (AA) mobilization and the activation of peroxisome proliferator-activated receptor gamma (PPARγ) nuclear receptor through the leukotriene B4 (LTB4) production. AA/LTB4/PPARγ/Dectin-1-MR signaling pathway is crucial for P17-mediated anti-fungal activity of h-MDMs, as indicated by the fact that the activation of this axis by P17 triggered ROS production and inflammasome-dependent IL-1ß release. Moreover, we showed that the increased anti-fungal immune response of h-MDMs by P17 was dependent on intracellular calcium mobilization triggered by the interaction of P17 with pertussis toxin-sensitive G-protein-coupled receptors on h-MDMs. Finally, we also demonstrated that P17-treated mice infected with C. albicans develop less severe gastrointestinal infection related to a higher efficiency of their macrophages to engulf Candida, to produce ROS and IL-1ß and to kill the yeasts. Altogether, these results identify P17 as an original activator of the fungicidal response of macrophages that acts upstream PPARγ/CLRs axis and offer new immunomodulatory therapeutic perspectives in the field of infectious diseases.

6.
Peptides ; 79: 103-13, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27058430

RESUMO

We have recently characterized bicarinalin as the most abundant peptide from the venom of the ant Tetramorium bicarinatum. This antimicrobial peptide is active against Staphylococcus and Enterobacteriaceae. To further investigate the antimicrobial properties of this cationic and cysteine-free peptide, we have studied its antibacterial, antifungal and antiparasitic activities on a large array of microorganisms. Bicarinalin was active against fifteen microorganisms with minimal inhibitory concentrations ranging from 2 and 25µmolL(-1). Cronobacter sakazakii, Salmonella enterica, Candida albicans, Aspergilus niger and Saccharomyces cerevisiae were particularly susceptible to this novel antimicrobial peptide. Resistant strains of Staphylococcus aureus, Pseudomonas aeruginosa and C. albicans were as susceptible as the canonical strains. Interestingly, bicarinalin was also active against the parasite Leishmania infantum with a minimal inhibitory concentrations of 2µmolL(-1). The bicarinalin pre-propeptide cDNA sequence has been determined using a combination of degenerated primers with RACE PCR strategy. Interestingly, the N-terminal domain of bicarinalin pre-propeptide exhibited sequence similarity with the pilosulin antimicrobial peptide family previously described in the Myrmecia venoms. Moreover, using SYTOX green uptake assay, we showed that, for all the tested microorganisms, bicarinalin acted through a membrane permeabilization mechanism. Two dimensional-NMR experiments showed that bicarinalin displayed a 10 residue-long α-helical structure flanked by two N- and C-terminal disordered regions. This partially amphipathic helix may explain the membrane permeabilization mechanism of bicarinalin observed in this study. Finally, therapeutic value of bicarinalin was highlighted by its low cytotoxicity against human lymphocytes at bactericidal concentrations and its long half-life in human serum which was around 15h.


Assuntos
Venenos de Formiga/farmacologia , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Antiprotozoários/farmacologia , Formigas , Sequência de Aminoácidos , Animais , Venenos de Formiga/química , Venenos de Formiga/genética , Venenos de Formiga/metabolismo , Antibacterianos/química , Antibacterianos/metabolismo , Antifúngicos/química , Antifúngicos/metabolismo , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Antiprotozoários/química , Antiprotozoários/metabolismo , Sequência de Bases , Permeabilidade da Membrana Celular , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Sequência Conservada , Meia-Vida , Humanos , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Proteínas de Insetos/farmacologia , Dose Letal Mediana , Linfócitos/efeitos dos fármacos , Linfócitos/fisiologia , Testes de Sensibilidade Microbiana , Modelos Moleculares , Filogenia , Estrutura Secundária de Proteína , Proteólise
7.
Malar J ; 14: 358, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26385579

RESUMO

BACKGROUND: Pregnancy-associated malaria (PAM) constitutes one of the most severe forms of malaria infection leading to fetal growth restriction and high risk of infant death. The severity of the pathology is largely attributed to the recruitment of monocytes and macrophages in the placenta which is evidenced by dysregulated inflammation found in placental blood. Importantly, CD36(+) monocytes/macrophages are also thought to participate in the tight control of the pro- and anti-inflammatory responses following Plasmodium detection through elimination of apoptotic cells and malaria-infected erythrocytes, internalization and recycling of oxidized forms of low-density lipoprotein and collaboration with TLR2 in pro-inflammatory response. Interestingly, previous work demonstrated that CD36 expression was upregulated on inflammatory macrophages following stimulation of the Nrf2 transcription factor, whilst the PPARγ pathway was inhibited and non-functional in the same inflammatory conditions. This current study examined the possible role of Nrf2-driven gene expression, CD36 and Haem-Oxygenase-1 (HO-1), in PAM clinical outcomes. METHODS: Clinical data and biological samples including peripheral blood mononuclear cells were collected from 27 women presenting PAM. Polychromatic flow cytometry was used to characterize innate immune cell subpopulations and quantify CD36 protein expression level on monocytes. mRNA levels of CD36, PPARγ, Nrf2 and HO-1 were determined by qPCR and related to clinical outcomes. Finally, the capacity of monocytes to modulate CD36 expression upon rosiglitazone or sulforaphane treatment, two respective PPARγ or Nrf2 activators, was also investigated. RESULTS: The CD36 receptor, mostly expressed by CD14(+) circulating monocytes, statistically correlated with increased infant birth weights. Interestingly, mRNA levels of the transcription factor Nrf2 and the enzyme HO-1 also correlated with lower parasitaemia and increased infant birth weight, while PPARγ mRNA levels did not. Finally, monocytes isolated from low infant birth weight pregnant women were capable of up-regulating CD36 via the Nrf2 pathway ex vivo. CONCLUSIONS: Altogether these results suggest that Nrf2-driven CD36 and HO-1 expression on innate immune cells could contribute to a protective and detoxifying mechanism during PAM. More powered and mechanistical studies are however needed to strengthen the conclusions of this study.


Assuntos
Antígenos CD36/genética , Heme Oxigenase-1/genética , Malária Falciparum/epidemiologia , Fator 2 Relacionado a NF-E2/genética , Parasitemia/epidemiologia , Plasmodium falciparum/fisiologia , Complicações Parasitárias na Gravidez/epidemiologia , Adolescente , Adulto , Benin/epidemiologia , Peso ao Nascer , Antígenos CD36/metabolismo , Feminino , Heme Oxigenase-1/metabolismo , Humanos , Recém-Nascido , Malária Falciparum/parasitologia , Monócitos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Parasitemia/parasitologia , Gravidez , Complicações Parasitárias na Gravidez/parasitologia , Regulação para Cima , Adulto Jovem
8.
Nat Commun ; 6: 6801, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25873311

RESUMO

Liver receptor homologue-1 (LRH-1) is a nuclear receptor involved in the repression of inflammatory processes in the hepatointestinal tract. Here we report that LRH-1 is expressed in macrophages and induced by the Th2 cytokine IL-13 via a mechanism involving STAT6. We show that loss-of-function of LRH-1 in macrophages impedes IL-13-induced macrophage polarization due to impaired generation of 15-HETE PPARγ ligands. The incapacity to generate 15-HETE metabolites is at least partially caused by the compromised regulation of CYP1A1 and CYP1B1. Mice with LRH-1-deficient macrophages are, furthermore, highly susceptible to gastrointestinal and systemic Candida albicans infection. Altogether, these results identify LRH-1 as a critical component of the anti-inflammatory and fungicidal response of alternatively activated macrophages that acts upstream from the IL-13-induced 15-HETE/PPARγ axis.


Assuntos
Candidíase/imunologia , Gastroenterite/imunologia , Interleucina-13/imunologia , Macrófagos/imunologia , PPAR gama/genética , Receptores Citoplasmáticos e Nucleares/genética , Animais , Western Blotting , Candida albicans , Imunoprecipitação da Cromatina , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/imunologia , Citocromo P-450 CYP1B1/genética , Citocromo P-450 CYP1B1/imunologia , Citocinas/imunologia , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Ácidos Hidroxieicosatetraenoicos/imunologia , Macrófagos Peritoneais/imunologia , Camundongos , PPAR gama/imunologia , Fagocitose/genética , Fagocitose/imunologia , Fenótipo , Reação em Cadeia da Polimerase em Tempo Real , Receptores Citoplasmáticos e Nucleares/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT6/metabolismo
9.
J Am Soc Nephrol ; 26(6): 1363-77, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25270069

RESUMO

Rhabdomyolysis can be life threatening if complicated by AKI. Macrophage infiltration has been observed in rat kidneys after glycerol-induced rhabdomyolysis, but the role of macrophages in rhabdomyolysis-induced AKI remains unknown. Here, in a patient diagnosed with rhabdomyolysis, we detected substantial macrophage infiltration in the kidney. In a mouse model of rhabdomyolysis-induced AKI, diverse renal macrophage phenotypes were observed depending on the stage of the disease. Two days after rhabdomyolysis, F4/80(low)CD11b(high)Ly6b(high)CD206(low) kidney macrophages were dominant, whereas by day 8, F4/80(high)CD11b(+)Ly6b(low)CD206(high) cells became the most abundant. Single-cell gene expression analyses of FACS-sorted macrophages revealed that these subpopulations were heterogeneous and that individual cells simultaneously expressed both M1 and M2 markers. Liposomal clodronate-mediated macrophage depletion significantly reduced the early infiltration of F4/80(low)CD11b(high)Ly6b(high)CD206(low) macrophages. Furthermore, transcriptionally regulated targets potentially involved in disease progression, including fibronectin, collagen III, and chemoattractants that were identified via single-cell analysis, were verified as macrophage-dependent in situ. In vitro, myoglobin treatment induced proximal tubular cells to secrete chemoattractants and macrophages to express proinflammatory markers. At day 30, liposomal clodronate-mediated macrophage depletion reduced fibrosis and improved both kidney repair and mouse survival. Seven months after rhabdomyolysis, histologic lesions were still present but were substantially reduced with prior depletion of macrophages. These results suggest an important role for macrophages in rhabdomyolysis-induced AKI progression and advocate the utility of long-term follow-up for patients with this disease.


Assuntos
Lesão Renal Aguda/etiologia , Lesão Renal Aguda/fisiopatologia , Macrófagos/metabolismo , Mioglobina/metabolismo , Rabdomiólise/complicações , Rabdomiólise/fisiopatologia , Animais , Células Cultivadas , Ácido Clodrônico/farmacologia , Modelos Animais de Doenças , Progressão da Doença , Citometria de Fluxo , Glicerol/farmacologia , Humanos , Macrófagos/classificação , Macrófagos/patologia , Masculino , Camundongos , Mioglobina/efeitos dos fármacos , Distribuição Aleatória , Fatores de Risco , Sensibilidade e Especificidade
10.
J Ethnopharmacol ; 157: 149-55, 2014 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-25251262

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Leaves and rhizomes of Renealmia thyrsoidea (Ruiz & Pav.) Poepp. & Endl. traditionally used in the Yanesha pharmacopoeia to treat skin infections such as leishmaniasis ulcers, or to reduce fever were chemically investigated to identify leishmanicidal compounds, as well as PPARγ activators. METHODS: Compounds were isolated through a bioassay-guided fractionation and their structures were determined via detailed spectral analysis. The viability of Leishmania amazonensis axenic amastigotes was assessed by the reduction of tetrazolium salt (MTT), the cytotoxicity on macrophage was evaluated using trypan blue dye exclusion method, while the percentage of infected macrophages was determined microscopically in the intracellular macrophage-infected assay. The CD36, mannose receptor (MR) and dectin-1 mRNA expression on human monocytes-derived macrophages was evaluated by quantitative real-time PCR. RESULTS: Six sesquiterpenes (1-6), one dihydrobenzofuranone (7) and four flavonoids (8-11) were isolated from the leaves. Alongside, two flavonoids (12-13) and five diarylheptanoids (14-18) were identified in the rhizomes. Leishmanicidal activity against Leishmania amazonensis axenic amastigotes was evaluated for all compounds. Compounds 6, 7, and 11, isolated from the leaves, showed to be the most active derivatives. Diarylheptanoids 14-18 were also screened for their ability to activate PPARγ nuclear receptor in macrophages. Compounds 17 and 18 bearing a Michael acceptor moiety strongly increased the expression of PPARγ target genes such as CD36, Dectin-1 and mannose receptor (MR), thus revealing interesting immunomodulatory properties. CONCLUSIONS: Phytochemical investigation of Renealmia thyrsoidea has led to the isolation of leishmanicidal compounds from the leaves and potent PPARγ activators from the rhizomes. These results are in agreement with the traditional uses of the different parts of Renealmia thyrsoidea.


Assuntos
Leishmania mexicana/efeitos dos fármacos , PPAR gama/efeitos dos fármacos , Extratos Vegetais/farmacologia , Zingiberaceae/química , Animais , Antiprotozoários/isolamento & purificação , Antiprotozoários/farmacologia , Humanos , Macrófagos/efeitos dos fármacos , Masculino , Medicina Tradicional , Camundongos , Camundongos Endogâmicos BALB C , PPAR gama/metabolismo , Folhas de Planta , Reação em Cadeia da Polimerase em Tempo Real , Rizoma
11.
Bioorg Med Chem Lett ; 24(16): 3819-22, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25027935

RESUMO

PPARγ and Nrf2 are important transcriptional factors involved in many signaling pathways, especially in the anti-infectious response of macrophages. Compounds bearing a Michael acceptor moiety are well known to activate such transcriptional factors, we thus evaluated the potency of α,ß-unsaturated lactones synthesized using fluorous phase organic synthesis. Compounds were first screened for their cytotoxicity in order to select lactones for PPARγ and Nrf2 activation evaluation. Among them, two α-methylene-γ-lactones were identified as potent dual activators of PPARγ and Nrf2 in macrophages.


Assuntos
4-Butirolactona/análogos & derivados , Antineoplásicos/farmacologia , Lactonas/farmacologia , Macrófagos/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , PPAR gama/metabolismo , 4-Butirolactona/síntese química , 4-Butirolactona/química , 4-Butirolactona/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lactonas/síntese química , Lactonas/química , Camundongos , Estrutura Molecular , Relação Estrutura-Atividade
12.
ACS Nano ; 8(2): 1350-63, 2014 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-24401079

RESUMO

Nanotherapy using targeted magnetic nanoparticles grafted with peptidic ligands of receptors overexpressed in cancers is a promising therapeutic strategy. However, nanoconjugation of peptides can dramatically affect their properties with respect to receptor recognition, mechanism of internalization, intracellular trafficking, and fate. Furthermore, investigations are needed to better understand the mechanism whereby application of an alternating magnetic field to cells containing targeted nanoparticles induces cell death. Here, we designed a nanoplatform (termed MG-IONP-DY647) composed of an iron oxide nanocrystal decorated with a ligand of a G-protein coupled receptor, the cholecystokinin-2 receptor (CCK2R) that is overexpressed in several malignant cancers. MG-IONP-DY647 did not stimulate inflammasome of Raw 264.7 macrophages. They recognized cells expressing CCK2R with a high specificity, subsequently internalized via a mechanism involving recruitment of ß-arrestins, clathrin-coated pits, and dynamin and were directed to lysosomes. Binding and internalization of MG-IONP-DY647 were dependent on the density of the ligand at the nanoparticle surface and were slowed down relative to free ligand. Trafficking of CCK2R internalized with the nanoparticles was slightly modified relative to CCK2R internalized in response to free ligand. Application of an alternating magnetic field to cells containing MG-IONP-DY647 induced apoptosis and cell death through a lysosomal death pathway, demonstrating that cell death is triggered even though nanoparticles of low thermal power are internalized in minute amounts by the cells. Together with pioneer findings using iron oxide nanoparticles targeting tumoral cells expressing epidermal growth factor receptor, these data represent a solid basis for future studies aiming at establishing the proof-of-concept of nanotherapy of cancers using ligand-grafted magnetic nanoparticles specifically internalized via cell surface receptors.


Assuntos
Morte Celular , Neoplasias das Glândulas Endócrinas/metabolismo , Magnetismo , Nanopartículas , Receptores Acoplados a Proteínas-G/metabolismo , Animais , Linhagem Celular , Neoplasias das Glândulas Endócrinas/patologia , Compostos Férricos/metabolismo , Gastrinas/metabolismo , Células HEK293 , Humanos , Macrófagos/metabolismo , Camundongos
13.
Pediatr Infect Dis J ; 33(7): 680-6, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24336095

RESUMO

BACKGROUND: Aspergillus fumigatus (Af) sensitization and persistent carriage are deleterious to lung function, but no consensus has been reached defining these medical entities. This work aimed to identify possible predictive factors for patients who become sensitized to Af, compared with a control group of non-sensitized Af carriers. METHODS: Between 1995 and 2007, 117 pediatric patients were evaluated. Demographic data, CFTR gene mutations, body mass index and FEV1 were recorded. The presence of Af in sputum, the levels of Af-precipitin, total IgE (t-IgE) and specific IgE to Af (Af-IgE) were determined. Patients were divided into 2 groups: (1) "sensitization": level of Af-IgE > 0.35 IU/mL with t-IgE level < 500 IU/mL and (2) "persistent or transient carriage": Af-IgE level ≤ 0.35 IU/mL with either an Af transient or persistent positive culture. A survival analysis was performed with the appearance of Af-IgE in serum as an outcome variable. RESULTS: Severe mutation (hazard ratio = 3.2), FEV1 baseline over 70% of theoretical value (hazard ratio = 4.9), absence of Pa colonization, catalase activity and previous azithromycin administration (hazard ratio = 9.8, 4.1 and 1.9, respectively) were predictive factors for sensitization. We propose a timeline of the biological events and a tree diagram for risk calculation. CONCLUSIONS: Two profiles of cystic fibrosis patients can be envisaged: (1) patients with nonsevere mutation but low FEV1 baselines are becoming colonized with Af or (2) patients with high FEV1 baselines who present with severe mutation are more susceptible to the Af sensitization and then to the presentation of an allergic bronchopulmonary aspergillosis event.


Assuntos
Anticorpos Antifúngicos/sangue , Aspergilose Broncopulmonar Alérgica/epidemiologia , Aspergillus fumigatus/imunologia , Aspergillus fumigatus/isolamento & purificação , Portador Sadio/epidemiologia , Fibrose Cística/complicações , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina E/sangue , Lactente , Masculino
14.
PLoS One ; 8(12): e84771, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24367694

RESUMO

Candida albicans produces a complex glycosphingolipid called phospholipomannan (PLM), which is present on the cell-wall surface of yeast and shed upon contact with host cells. The glycan moiety of PLM is composed of ß-mannosides with degrees of polymerization up to 19 in C. albicans serotype A. PLM from serotype B strains displays a twofold decrease in the length of the glycan chains. In this study we compared the proinflammatory activities of PLMs purified from C. albicans serotype A and serotype B strains and from a bmt6Δ mutant of C. albicans, whose PLM is composed of short truncated oligomannosidic chain. We found that PLMs activate caspase-1 in murine macrophage cell line J774 independent of the glycan chain length although IL-1ß secretion is more intense with long glycan chain. None of the tested PLMs stimulate ROS production, indicating that caspase-1 activation may occur through a ROS-independent pathway. On the other hand, only long-chain oligomannosides present on PLM from serotype A strain (PLM-A) are able to induce TNF-α production in macrophages, a property that is not affect by blocking endocytosis through latrunculin A treatment. Finally, we demonstrate that soluble and not cell surface-bound galectin-3, is able to potentiate PLM-A-induced TNF-α production in macrophages. PLMs from C. albicans serotype B and from bmt6∆ mutant are not able to induce TNF-α production and galectin-3 pretreatment does not interfere with this result. In conclusion, we show here that PLMs are able to evoke a proinflammatory state in macrophage, which is in part dependent on their glycosylation status. Long-glycan chains favor interaction with soluble galectin-3 and help amplify inflammatory response.


Assuntos
Candida albicans/metabolismo , Glicolipídeos/metabolismo , Inflamação/metabolismo , Macrófagos/metabolismo , beta-Manosidase/metabolismo , Análise de Variância , Animais , Western Blotting , Caspase 1/metabolismo , Linhagem Celular , Eletroforese/métodos , Galectina 3/metabolismo , Camundongos , Polimerização , Espécies Reativas de Oxigênio/metabolismo , Especificidade da Espécie , Fator de Necrose Tumoral alfa/metabolismo
15.
J Ethnopharmacol ; 149(1): 75-83, 2013 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-23769983

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Crinum latifolium L. (CL) leaf extracts have been traditionally used in Vietnam and are now used all over the world for the treatment of prostate cancer. However, the precise cellular mechanisms of the action of CL extracts remain unclear. AIM OF THE STUDY: To examine the effects of CL samples on the anti-tumour activity of peritoneal murine macrophages. MATERIALS AND METHODS: The properties of three extracts (aqueous, flavonoid, alkaloid), one fraction (alkaloid), and one pure compound (6-hydroxycrinamidine) obtained from CL, were studied (i) for redox capacities (DPPH and bleaching beta-carotene assays), (ii) on murine peritoneal macrophages (MTT assay) and on lymphoma EL4-luc2 cells (luciferine assay) for cytotoxicity, (iii) on macrophage polarization (production of ROS and gene expression by PCR), and (iv) on the tumoricidal functions of murine peritoneal macrophages (lymphoma cytotoxicity by co-culture with syngeneic macrophages). RESULTS: The total flavonoid extract with a high antioxidant activity (IC50=107.36 mg/L, DPPH assay) showed an inhibitory action on cancer cells. Alkaloid extracts inhibited the proliferation of lymphoma cells either by directly acting on tumour cells or by activating of the tumoricidal functions of syngeneic macrophages. The aqueous extract induced mRNA expression of tumour necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and interleukin 6 (IL-6) indicating differentiation of macrophages into pro-inflammatory M1 polarized macrophages. The total flavonoid, alkaloid extracts and an alkaloid fraction induced the expression of the formyl peptide receptor (FPR) on the surface of the polarized macrophages that could lead to the activation of macrophages towards the M1 phenotype. Aqueous and flavonoid extracts enhanced NADPH quinine oxido-reductase 1 (NQO1) mRNA expression in polarized macrophages which could play an important role in cancer chemoprevention. All the samples studied were non-toxic to normal living cells and the pure alkaloid tested, 6-hydroxycrinamidine, was not active in any of the models investigated. CONCLUSIONS: Our results indicate that CL extracts and alkaloid fraction (but not pure 6-hydroxycrinamidine) inhibit the proliferation of lymphoma cells in multiple pathways. Our results are in accordance with traditional usage and encourage further studies and in vivo assays.


Assuntos
Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Crinum/química , Etnofarmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Extratos Vegetais/farmacologia , Alcaloides/isolamento & purificação , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Crinum/crescimento & desenvolvimento , Humanos , Macrófagos Peritoneais/citologia , Macrófagos Peritoneais/imunologia , Medicina Tradicional do Leste Asiático , Camundongos , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Espécies Reativas de Oxigênio/metabolismo , Vietnã
16.
Immunity ; 38(5): 1038-49, 2013 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-23684988

RESUMO

Macrophages act as the primary effector cells during Leishmania infection through production of reactive oxygen species (ROS) and interleukin-1ß (IL-1ß). However, how macrophage-killing mechanisms are activated during Leishmania-macrophage interactions is poorly understood. Here, we report that the macrophage response against Leishmania infantum in vivo is characterized by an M2b-like phenotype and C-type lectin receptors (CLRs) signature composed of Dectin-1, mannose receptor (MR), and the DC-SIGN homolog SIGNR3 expression. Dectin-1 and MR were crucial for the microbicidal response as indicated by the fact that they activated Syk-p47phox and arachidonic acid (AA)-NADPH oxidase signaling pathways, respectively, needed for ROS production and also triggered Syk-coupled signaling for caspase-1-induced IL-1ß secretion. In contrast, SIGNR3 has divergent functions during Leishmania infantum pathogenesis; this CLR favored parasite resilience through inhibition of the LTB4-IL-1ß axis. These pathways also operated during infection of primary human macrophages. Therefore, our study promotes CLRs as potential targets for treatment, diagnosis, and prevention of visceral leishmaniasis.


Assuntos
Antígenos CD/metabolismo , Lectinas Tipo C/metabolismo , Leishmania infantum/imunologia , Macrófagos/imunologia , Lectinas de Ligação a Manose/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Ácido Araquidônico/metabolismo , Caspase 1/metabolismo , Células Cultivadas , Humanos , Interleucina-1beta/antagonistas & inibidores , Interleucina-1beta/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lectinas Tipo C/imunologia , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/parasitologia , Leucotrieno B4/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NADPH Oxidases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Interferência de RNA , RNA Interferente Pequeno , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Quinase Syk
17.
PLoS One ; 7(9): e45906, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23029306

RESUMO

The search for new antimalarial chemotherapy has become increasingly urgent due to parasite resistance to current drugs. Ellagic acid (EA) is a polyphenol, recently found in various plant products, that has effective antimalarial activity in vitro and in vivo without toxicity. To further understand the antimalarial mechanism of action of EA in vitro, we evaluated the effects of EA, ascorbic acid and N-acetyl-L-cysteine (NAC), alone and/or in combination on the production of reactive oxygen species (ROS) during the trophozoite and schizonte stages of the erythrocytic cycle of P. falciparum. The parasitized erythrocytes were pre-labelled with DCFDA (dichlorofluorescein diacetate). We showed that NAC had no effect on ROS production, contrary to ascorbic acid and EA, which considerably reduced ROS production. Surprisingly, EA reduced the production of the ROS with concentrations (6.6×10(-9) - 6.6×10(-6) M) ten-fold lower than ascorbic acid (113×10(-6) M). Additionally, the in vitro drug sensitivity of EA with antioxidants showed that antiplasmodial activity is independent of the ROS production inside parasites, which was confirmed by the additive activity of EA and desferrioxamine. Finally, EA could act by reducing the glutathione content inside the Plasmodium parasite. This was consolidated by the decrease in the antiplasmodial efficacy of EA in the murine model Plasmodium yoelii- high GSH strain, known for its high glutathione content. Given its low toxicity and now known mechanism of action, EA appears as a promising antiplasmodial compound.


Assuntos
Antimaláricos/farmacologia , Antioxidantes/farmacologia , Ácido Elágico/farmacologia , Glutationa/fisiologia , Plasmodium falciparum/efeitos dos fármacos , Acetilcisteína/farmacologia , Animais , Antioxidantes/metabolismo , Antioxidantes/fisiologia , Ácido Ascórbico/farmacologia , Butionina Sulfoximina/farmacologia , Células Cultivadas , Desferroxamina/farmacologia , Sinergismo Farmacológico , Inibidores Enzimáticos/farmacologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Eritrócitos/parasitologia , Glutationa/metabolismo , Glutationa/farmacologia , Humanos , Concentração Inibidora 50 , Camundongos , Oxirredução , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/metabolismo , Plasmodium yoelii/efeitos dos fármacos , Espécies Reativas de Oxigênio , Sideróforos/farmacologia
18.
Scand J Infect Dis ; 44(11): 842-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22831545

RESUMO

BACKGROUND: Cystic fibrosis (CF) patients presenting with persistent carriage of, or sensitization to, Aspergillus fumigatus are often treated with antifungal therapies because the presence of the fungus is commonly thought to impede lung function, even in the absence of allergic bronchopulmonary aspergillosis (ABPA). The aim of this study was to assess Aspergillus-related status modulating the forced expiratory volume in 1 s (FEV1) of CF patients. METHODS: From 1995 to 2007, 251 patients were evaluated. Demographic data, cystic fibrosis transmembrane conductance regulator gene (CFTR) mutations, body mass index, and FEV(1) were recorded. The presence of A. fumigatus and Pseudomonas aeruginosa in sputum and the levels of A. fumigatus precipitin, total IgE (t-IgE), and specific anti-A. fumigatus IgE (Af-IgE) were determined. Patients were divided into 3 groups: (1) ABPA: A. fumigatus precipitin ≥3 lines, Af-IgE > 0.35 IU/ml, and t-IgE ≥500 IU/ml; (2) sensitization: Af-IgE > 0.35 IU/ml but t-IgE < 500 IU/ml; and (3) persistent carriage: Af-IgE ≤ 0.35 IU/ml with either an A. fumigatus persistent positive culture or an A. fumigatus precipitin ≥3 lines, provided this serological finding had been found associated with at least 1 A. fumigatus-positive culture. The remaining patients represented the control group. A multivariate analysis was carried out with FEV(1) as the outcome variable. RESULTS: ABPA, sensitization, and persistent carriage were significantly associated with a larger decline in FEV1 compared with the control group, with odds ratios of 15.9, 14.9, and 10.7, respectively. This association was independent of other associated factors (P. aeruginosa transient detection, age, being underweight, and low FEV1 at baseline). CONCLUSIONS: In addition to ABPA, sensitization and persistent carriage appear to have an impact on pulmonary function in CF patients.


Assuntos
Aspergilose Broncopulmonar Alérgica/complicações , Aspergillus fumigatus/imunologia , Portador Sadio/microbiologia , Fibrose Cística/microbiologia , Adolescente , Aspergilose Broncopulmonar Alérgica/epidemiologia , Aspergilose Broncopulmonar Alérgica/imunologia , Aspergilose Broncopulmonar Alérgica/fisiopatologia , Índice de Massa Corporal , Portador Sadio/imunologia , Criança , Fibrose Cística/epidemiologia , Fibrose Cística/imunologia , Fibrose Cística/fisiopatologia , Progressão da Doença , Feminino , Volume Expiratório Forçado/fisiologia , França/epidemiologia , Humanos , Masculino , Análise Multivariada , Razão de Chances , Adulto Jovem
19.
J Ethnopharmacol ; 143(1): 24-32, 2012 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-22732725

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Vitex trifolia L. (Labiatae), a widespread tree found from the Asia-Pacific to the east Africa regions is used in the traditional medicine of the Pacific islands to treat inflammatory-associated conditions. AIM OF THE STUDY: We herein evaluated its in vitro regulatory effects on the expression profile of lipopolysaccharide (LPS)-induced inflammatory genes focusing on regulation of chemokines C-X-C motif 10 (CXCL-10) and C-C motif ligand 3 (CCL-3) and cyclo-oxygenase (COX)-2. Furthermore, the plant effect on the LPS-mediated activation of Nuclear Factor kappa B (NF-κB) was also studied. MATERIALS AND METHODS: Aqueous extract of Vitex trifolia leaves was prepared and evaluated for its effect on LPS-induced stress and toxicity-related genes in RAW 264.7 macrophage cells using RT(2) Profiler Polymerase Chain Reaction (PCR) Array System. Effects of the extract on LPS-induced chemokines CCL-3 and CXCL-10, COX-2, and NF-κB p50 and p65 mRNA levels were also studied using Reverse Transcription quantitative PCR (RT-qPCR) technique. Translocation of the nuclear factor was further assessed by measuring its nuclear p65 subunit via an ELISA-based TransAM method. RESULTS: Vitex trifolia extract at 5000µg/ml exerted a significant inhibitory effect on the expression of various LPS-induced inflammatory genes in RAW 264.7 cells after 8h of incubation time. Using RT-qPCR, this anti-inflammatory effect was further confirmed by significant inhibition of CCL-3 and CXCL-10 mRNA production in LPS-stimulated RAW 264.7 cells upon treatment with 2500µg/ml of Vitex trifolia extract. Furthermore, the inhibitory activity of this plant on LPS-induced COX-2 mRNA was also observed at a concentration of 2500µg/ml in a time-dependent manner. TransAM assays showed that LPS-induced NF-κB translocation was also inhibited by Vitex trifolia extract even at a concentration of extract as low as 250µg/ml. RT-qPCR assays showed that aqueous extract of Vitex trifolia leaves had a significant inhibitory activity on LPS-induced p50 mRNA synthesis. Interestingly, however, no effect on p65 subunit mRNA expression was observed. Moreover, PCR array analysis showed that LPS-induced inflammatory and apoptosis genes under NF-κB control are also repressed by the extract. CONCLUSION: The anti-inflammatory properties of Vitex trifolia extract seem associated with inhibition of NF-κB translocation through a reduction in the expression level of NF-κB p50 but interestingly not p65 subunit mRNA. The regulatory effects of Vitex trifolia on NF-κB and consequently on inflammation mediators such as chemokines CCL-3 and CXCL-10, and COX-2 provide new evidence of its efficacy and emphasise its high potential therapeutic value. However, further in vivo experiments are still required to validate its utilization as a remedy against inflammatory diseases.


Assuntos
Anti-Inflamatórios/uso terapêutico , Mediadores da Inflamação/metabolismo , Inflamação/tratamento farmacológico , NF-kappa B/antagonistas & inibidores , Fitoterapia , Extratos Vegetais/uso terapêutico , Vitex , Animais , Anti-Inflamatórios/farmacologia , Transporte Biológico/efeitos dos fármacos , Quimiocina CCL3/genética , Quimiocina CCL3/metabolismo , Quimiocina CXCL10/genética , Quimiocina CXCL10/metabolismo , Quimiocinas/genética , Quimiocinas/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/farmacologia , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Expressão Gênica/efeitos dos fármacos , Inflamação/genética , Inflamação/metabolismo , Mediadores da Inflamação/antagonistas & inibidores , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , NF-kappa B/genética , Subunidade p50 de NF-kappa B/antagonistas & inibidores , Subunidade p50 de NF-kappa B/genética , Extratos Vegetais/farmacologia , RNA Mensageiro/metabolismo , Fator de Transcrição RelA/antagonistas & inibidores , Fator de Transcrição RelA/genética
20.
Am J Physiol Renal Physiol ; 302(11): F1409-17, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22419690

RESUMO

Modified urinary fluid shear stress (FSS) induced by variations of urinary fluid flow and composition is observed in early phases of most kidney diseases. Recently, we reported that renal tubular FSS promotes endothelial cell activation and subsequent adhesion of human monocytes, thereby suggesting that changes in urinary FSS can induce the development of inflammation (Miravète M, Klein J, Besse-Patin A, Gonzalez J, Pecher C, Bascands JL, Mercier-Bonin M, Schanstra JP, Buffin-Meyer B, BBRC 407: 813-817, 2011). Here, we evaluated the influence of tubular FSS on monocytes as they play an important role in the progression of inflammation in nephropathies. Human renal tubular cells (HK-2) were exposed to FSS 0.01 Pa for 30 min or 5 h. Treatment of human THP-1 monocytes with the resulting conditioned medium (FSS-CM) modified the expression of macrophage differentiation markers, suggesting differentiation toward the inflammatory M1-type macrophage. The effect was confirmed in freshly isolated human monocytes. In contrast to endothelial cells, the activation of monocytes by FSS-CM did not require TNF-α. Cytokine array analysis of FSS-CM showed that FSS modified secretion of cytokines by HK-2 cells, particularly by increasing secretion of TGF-ß and by decreasing secretion of C-C chemokine ligand 2 (CCL2). Neutralization of TGF-ß or CCL2 supplementation attenuated the effect of FSS-CM on macrophage differentiation. Finally, FSS-injured HK-2 cells expressed and secreted early biomarkers of tubular damage such as kidney injury molecule 1 and neutrophil gelatinase-associated lipocalin. In conclusion, changes in urinary FSS should now also be considered as potential insults for tubular cells that initiate/perpetuate interstitial inflammation.


Assuntos
Inflamação/patologia , Túbulos Renais/fisiologia , Ativação de Macrófagos/fisiologia , Monócitos/fisiologia , Proteínas da Fase Aguda/metabolismo , Animais , Linhagem Celular , Meios de Cultivo Condicionados , Citocinas/metabolismo , Receptor Celular 1 do Vírus da Hepatite A , Humanos , Técnicas In Vitro , Inflamação/metabolismo , Túbulos Renais/patologia , Lipocalina-2 , Lipocalinas/metabolismo , Glicoproteínas de Membrana/metabolismo , Monócitos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores Virais/metabolismo , Estresse Mecânico , Fator de Necrose Tumoral alfa/metabolismo , Urina/fisiologia , Urodinâmica/fisiologia
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