Elevated NS1 serum levels reduce CD119 expression and CXCL-10 synthesis in patients with dengue hemorrhagic fever

ABSTRACT Background: The intensity of dengue virus (DV) replication and circulating non-structural protein 1 (NS1) levels may promote changes in the human immune response and favor severe forms of infection. We investigated the correlations between NS1 with CXCL-8, CXCL-10, IFN-γ, and IL-12p40 serum levels, and IFN-γ receptor α chain (CD119) expression, and CXCL10 production by peripheral blood mononuclear cells (PBMCs) stimulated with recombinant IFN-γ in DV-infected patients with different clinical forms. Methods: Dengue virus NS1, CXCL-8, CXCL-10, IFN-γ, and IL-12p40 serum levels were measured in 152 DV-infected patients with different clinical forms and 20 non-infected individuals (NI) using enzyme-linked immunosorbent assay (ELISA). In addition, we investigated the CXCL-10 production after in vitro IFN-γ stimulation of PBMCs from 48 DV-infected individuals (with different clinical forms of dengue fever) and 20 NI individuals using ELISA, and CD119 expression on CD14+ cells with flow cytometry. Results: Patients with dengue hemorrhagic fever (DHF) had significantly higher NS1, CXCL-8, and CXCL-10 serum levels than those with classic dengue fever (DF). The response of PBMCs to IFN-γ stimulation was lower in patients with DHF than in those with DF or dengue with complications (DWC), with lower CD119 expression and reduced CXCL-10 synthesis. In addition, these alterations are associated with high NS1 serum levels. Conclusions: Patients with DHF reported high NS1 levels, low CD119 expression, and low CXCL-10 synthesis in PBMCs, which may be associated with infection progression and severity.

IL-27 regulates IL-4-induced chemokine production in human bronchial epithelial cells.

IL-4 coordinates the Th2-type immune response in inflammatory diseases such as asthma. IL-27 can inhibit the development of both Th2 and Th1 cells. However, IL-27 can also drive naïve T cells to differentiate toward the Th1 phenotype. In this study, we investigated the effects of IL-27 on the activation of IL-4-induced human bronchial epithelial cells (BEAS-2B). Compared to controls, both IL-4 and IL-27 (25-100 ng/mL) increased the concentrations of CCL2 and IL-8 in a dose-dependent manner. However, compared to cells stimulated individually with IL-4 or IL-27, treatment with a combination of both cytokines reduced CCL2 and IL-8 concentrations in a dose- and time-dependent manner. IL-4 increased the activation of p38 MAPK, ERK1/2, STAT6 and NF-κB, while IL-27 increased the activation of p38 MAPK and ERK1/2 but not STAT6 and NF-κB. Compared to IL-4-stimulated cells, cells treated with both IL-27 and IL-4 displayed decreased activation of STAT6 and NF-κB but not ERK1/2 and p38 MAPK. Taken together, these results suggest that IL-27 plays a pro-inflammatory role when administered alone but downregulates bronchial epithelial cell activation when combined with IL-4. Therefore, IL-27 may be an interesting target for the treatment of Th2 inflammatory diseases.

Agaphelin modulates the activation of human bronchial epithelial cells induced by lipopolysaccharide and IL-4.

Sand fly saliva presents molecules with potential to development of compounds for treatment of inflammatory diseases. Agaphelin, isolated from the saliva of the mosquito Anopheles gambiae, demonstrates anti-inflammatory properties such as neutrophils chemotaxis inhibition. Here, we extend these results and evaluated the role of agaphelin (0.1-100 nM) in an in vitro model consisting in the activation of human bronchial epithelial cells (BEAS-2B) by IL-4 (50 ng/mL) or lipopolysaccharide (LPS; 10 ng/mL). Agaphelin is non-cytotoxic for BEAS-2B cells. Notably, agaphelin markedly reduces CCL2 and IL-8 production induced by IL-4 or LPS, without altering the IL-10 production. The TLR4 expression and STAT1 phosphorylation induced by LPS were inhibited by agaphlin. In addition, agaphelin decreased the phosphorylation of STAT6 induce by IL-4, whose effect was independent of IL-4-binding activity. Taken together, these findings identify agaphelin as a potential anti-inflammatory therapeutic agent for airway inflammations.

AT-RvD1 modulates the activation of bronchial epithelial cells induced by lipopolysaccharide and Dermatophagoides pteronyssinus.

Bronchial epithelial cells are essential to airways homeostasis; however, they are also involved in exacerbation of airway inflammatory responses of patients with conditions such as asthma. Dermatophagoides pteronyssinus (Dp), the most important allergen, and lipopolysaccharide (LPS), both of which are present in house dust mites (HDM), can activate immune and structural cells (such as bronchial epithelial cells) and modulate the airway inflammation in asthma patients. Resolvin D1 (RvD1) and its epimer aspirin-triggered-resolvin D1 (AT-RvD1) are lipid mediators that are produced during the resolution of inflammation and demonstrate anti-inflammatory and pro-resolution effects in several experimental models including experimental models of allergic airway inflammation. Here, we evaluated the effects of AT-RvD1 (10-12-10-10 M) on human bronchial epithelial cells (BEAS-2B) stimulated with LPS (2µg/ml) or Dp (10µg/ml). After 24h, the C-C motif chemokine ligand 2 (CCL-2) production was increased in cells that had been stimulated with LPS and Dp compared to the control. However, AT-RvD1 (10-11 and 10-10 M) significantly reduced the concentration of CCL-2 in a manner that was dependent on the N-formyl peptide receptor 2 (FPR2/ALX) and nuclear factor kappa B (NF-κB) pathways in cells stimulated with LPS or Dp compared to controls. In addition, AT-RvD1 reduced the phosphorylation of signal transducer and activator of transcription (STAT)6 and STAT1 in cells stimulated with Dp and LPS, respectively. In conclusion, AT-RvD1 demonstrated significant anti-inflammatory effects in bronchial epithelial cells that were stimulated with LPS or Dp, which provides new perspectives for therapeutic strategies to control inflammatory airway diseases.

Dieta elevada em carboidratos complexos minimiza necessidade de suplementação durante jogo-treino de rúgbi: foco no sistema imune / Diet high in complex carbohydrates minimizes necessity for supplementation during rugby training game: focus on immune system / Una dieta elevada en hidratos de carbono complejos minimiza la necesidad de suplementación durante el entrenamiento en el deporte del rugby: foco en el sistema inmunitario

Resumo O estudo analisou a imunidade oral após treino de rúgbi em atletas submetidos à dieta com alto teor de carboidratos (DATC). Em estudo randomizado, duplo-cego e placebo controlado, 20 atletas consumiram DATC por três dias antes do experimento. Os atletas receberam aleatoriamente bebida carboidratada (CHO) ou placebo (PLA) e participaram de duas sessões de treino de rúgbi, separados por sete dias. Coletas de saliva foram feitas antes (Pré-E), imediatamente após (Pós-E) e 1 h após (1 h Pós-E) o jogo-treino. Houve diferença significativa em taxa de secreção de IgA-s para PLA somente no tempo 1 h Pós-E. DATC, dias antes de treino de rúgbi, preserva função imunológica oral independente da suplementação de CHO durante treino.

Abstract The study analyzed the oral immunity after rugby training in athletes undergoing diet high in carbohydrates (DATC). In a randomized, double-blind, placebo-controlled, 20 athletes consumed DATC for three days before the experiment. The athletes were randomly carbohydrate drink (CHO) or placebo (PLA) and participated in two training sessions of rugby, separated by seven days. Saliva samples were taken before (Pre-E), immediately after (Post-E) and 1 h after (1 h post-E) training. Significant difference in rate of s-IgA secretion to PLA only at time 1 h post-E. DATC, days before training rugby, preserves immune function independent of oral CHO supplementation during training.

Resumen El estudio analizó la inmunidad oral después del entrenamiento de rugby en jugadores sometidos a una dieta elevada en hidratos de carbono (DEHC). En un estudio aleatorizado, a doble ciego, controlado con placebo, 20 jugadores consumieron una DEHC durante 3 días antes del experimento. Los jugadores recibieron aleatoriamente bebida de hidratos de carbono (CHO) o placebo (PLA), y participaron en dos sesiones de entrenamiento de rugby, separadas entre sí 7 días. Las muestras de saliva fueron antes (pre-E), inmediatamente después (post-E) y 1 hora después (1 h post-E). Hubo una diferencia significativa en la tasa de secreción de s-IgA a PLA sólo en 1 h post-E. La DEHC, días antes de la sesión de rugby, preserva la función inmunológica independientemente de la suplementación de CHO durante el entrenamiento.

Association of inflammation, dyslipidemia, obesity and physical activity status in children

The aim of this study was to verify the association between inflammatory biomarkers, dyslipidemia, obesity and physical activity status in 10-years old children. Ninety-four children participated in this study and were classified into eutrophic (n=36), overweight (n=34) or obese (n=24) according to their body mass index (BMI). The genic expression of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α) and chemokine C-C motif ligand 2 (CCL-2) mRNA; the serum concentration of high-density lipoprotein cholesterol (HDL-c) and triglycerides; BMI, percentage of body fat (% BF) and waist circumference; and the number of steps per day were determined. The expression of IL-6, TNF-α and CCL-2 were associated (p < 0.05) positively with serum triglycerides, BMI, % BF and waist circumference, and negatively with serum HDL-c. No association (p > 0.05) between pro-inflammatory biomarkers and number of steps per day was found

The anti-inflammatory and pro-resolution effects of aspirin-triggered RvD1 (AT-RvD1) on peripheral blood mononuclear cells from patients with severe asthma.

Asthma is an inflammatory disease that is characterized by a predominance of eosinophils and/or neutrophils in the airways. In the resolution of inflammation, lipid mediators such as resolvin D1 (RvD1) and its epimer aspirin-triggered RvD1 (AT-RvD1) are produced and demonstrate anti-inflammatory and pro-resolution effects. In experimental models such as airway allergic inflammation induced by ovalbumin in mice, RvD1 and AT-RvD1 alleviate some of the most important phenotypes of asthma. Here, we demonstrated the effects of AT-RvD1 on peripheral blood mononuclear cells (PBMCs) from healthy individuals and patients with severe asthma stimulated with lipopolysaccharide (LPS) or Dermatophagoides pteronyssinus (DM). AT-RvD1 (100nM) reduced the concentration of TNF-α in PBMCs from healthy individuals and patients with severe asthma stimulated with LPS or DM. In addition, AT-RvD1 lowered the production of IL-10 only in PBMCs from patients with severe asthma stimulated with LPS. These effects were associated in part with decreasing NF-κB activation. Moreover, AT-RvD1 significantly increased phagocytosis of apoptotic neutrophils by monocytes from patients with severe asthma. In conclusion, AT-RvD1 demonstrated both anti-inflammatory and pro-resolution effects in PBMCs from patients with severe asthma and could become in the future an alternative treatment for asthma.

AT-RvD1 modulates CCL-2 and CXCL-8 production and NF-κB, STAT-6, SOCS1, and SOCS3 expression on bronchial epithelial cells stimulated with IL-4.

Bronchial epithelial cells represent the first line of defense against microorganisms and allergens in the airways and play an important role in chronic inflammatory processes such as asthma. In an experimental model, both RvD1 and AT-RvD1, lipid mediators of inflammation resolution, ameliorated some of the most important phenotypes of experimental asthma. Here, we extend these results and demonstrate the effect of AT-RvD1 on bronchial epithelial cells (BEAS-2B) stimulated with IL-4. AT-RvD1 (100 nM) decreased both CCL2 and CXCL-8 production, in part by decreasing STAT6 and NF-κB pathways. Furthermore, the effects of AT-RvD1 were ALX/FRP2 receptor dependent, as the antagonist of this receptor (BOC1) reversed the inhibition of these chemokines by AT-RvD1. In addition, AT-RvD1 decreased SOCS1 and increased SOCS3 expression, which play important roles in Th1 and Th17 modulation, respectively. In conclusion, AT-RvD1 demonstrated significant effects on the IL-4-induced activation of bronchial epithelial cells and consequently the potential to modulate neutrophilic and eosinophilic airway inflammation in asthma. Taken together, these findings identify AT-RvD1 as a potential proresolving therapeutic agent for allergic responses in the airways.

The effects of proresolution of ellagic acid in an experimental model of allergic airway inflammation.

Asthma is a disease of airway inflammation characterized by airway hyperresponsiveness, eosinophilic inflammation, and hypersecretion of mucus. Ellagic acid, a compound derived from medicinal plants and fruits, has shown anti-inflammatory activity in several experimental disease models. We used the classical experimental model, in BALB/c mice, of sensibilization with ovalbumin to determine the effect of ellagic acid (10 mg/kg; oral route) in the resolution of allergic airways response. Dexamethasone (1 mg/kg; subcutaneous route) was used as a positive control. The control group consisted of nonimmunized mice that received challenge with ovalbumin. Ellagic acid and dexamethasone or vehicle (water) were administered before or after intranasal allergen challenge. Ellagic acid accelerated the resolution of airways inflammation by decreasing total leukocytes and eosinophils numbers in the bronchoalveolar lavage fluid (BALF), the mucus production and lung inflammation in part by reducing IL-5 concentration, eosinophil peroxidase (EPO) activity, and P-selectin expression, but not activator protein 1 (AP-1) and nuclear factor kappa B (NF-κB) pathways. In addition, ellagic acid enhanced alveolar macrophage phagocytosis of IgG-OVA-coated beads ex vivo, a new proresolving mechanism for the clearance of allergen from the airways. Together, these findings identify ellagic acid as a potential therapeutic agent for accelerating the resolution of allergic airways inflammation.