IL-33 drives airway hyper-responsiveness through IL-13-mediated mast cell: airway smooth muscle crosstalk

Background

Mast cell localization within the airway smooth muscle (ASM)-bundle plays an important role in the development of airway hyper-responsiveness (AHR). Genomewide association studies implicate the ‘alarmin’ IL-33 in asthma, but its role in mast cell–ASM interactions is unknown.

Objectives

We examined the expression and functional role of IL-33 in bronchial biopsies of patients with and without asthma, ex vivo ASM, mast cells, cocultured cells and in a mouse model system.

Methods

IL-33 protein expression was assessed in human bronchial tissue from 9 healthy controls, and 18 mild-to-moderate and 12 severe asthmatic patients by immunohistochemistry. IL-33 and ST2 mRNA and protein expression in human-derived ASM, epithelial and mast cells were assessed by qPCR, immunofluorescence and/or flow cytometry and ELISA. Functional assays were used to assess calcium signalling, wound repair, proliferation, apoptosis and contraction. AHR and inflammation were assessed in a mouse model.

Results

Bronchial epithelium and ASM expressed IL-33 with the latter in asthma correlating with AHR. ASM and mast cells expressed intracellular IL-33 and ST2. IL-33 stimulated mast cell IL-13 and histamine secretion independent of FcεR1 cross-linking and directly promoted ASM wound repair. Coculture of mast cells with ASM activated by IL-33 increased agonist-induced ASM contraction, and in vivo IL-33 induced AHR in a mouse cytokine installation model; both effects were IL-13 dependent.

Conclusion

IL-33 directly promotes mast cell activation and ASM wound repair but indirectly promotes ASM contraction via upregulation of mast cell-derived IL-13. This suggests that IL-33 may present an important target to modulate mast cell–ASM crosstalk in asthma.

Association of G1359A polymorphism of the cannabinoid receptor gene (CNR1) with macronutrient intakes in obese females

BACKGROUND

The endogenous cannabinoid system plays a role in metabolic aspects of body weight and feeding behaviour. A polymorphism (1359 G/A) (rs1049353) of the CB1 gene was reported as a common polymorphism in the Caucasian population. The present study aimed to investigate the association of the polymorphism (G1359A) of the CB1 receptor gene on macronutrient intake in females with obesity.

METHODS

A sample of 896 females was analysed. A bioimpedance measurement, a blood pressure measurement, a serial assessment of nutritional intake with 3 days of written food records, and a biochemical analysis were all performed. The genotype of the CNR1 receptor gene polymorphism (rs1049353) was studied.

RESULTS

Five hundred and sixteen patients (57.6%) had the genotype G1359G (non-A carriers) and 380 (42.4%) patients had G1359A (328 patients, 36.6%) or A1359A (52 patients, 5.8%) (A carriers). Triglycerides and high-density lipoprotein (HDL) cholesterol levels were higher in A non-A allele carriers than non-A allele carriers. The intakes of dietary cholesterol and saturated fat for the upper tertile (T3) compared to the baseline tertile were inversely associated with the CB1-R 1359 G/A polymorphism [odds ratio (OR) = 0.59; 95% confidence interval (CI) = 0.30-0.92 and OR = 0.66; 95% CI = 0.39-0.91, respectively]. These data were observed in the second tertile (T2) (OR = 0.61; 95% CI = 0.29-0.94 and OR = 0.58; 95% CI = 0.31-0.90, respectively).

CONCLUSIONS

The present study reports an association of the A allele with a better lipid profile (triglycerides and HDL cholesterol) than non-A allele carriers. In addition, this polymorphism is associated with a specific macronutrient intake, as well as with low cholesterol and fat saturated intakes.

Effect of rs6923761 gene variant of glucagon-like peptide 1 receptor on metabolic response and weight loss after a 3-month intervention with a hypocaloric diet

BACKGROUND

Studies of the GLP-1 receptor (GLP-1 R) have been directed at identifying polymorphisms in the GLP-1 R gene that may be a contributing factor in the pathogenesis of obesity and cardiovascular risk factors. Nevertheless, the role of GLP-1 R variants on body weight response after dietary intervention has not been evaluated.

OBJECTIVE

We decided to analyze the effects of the rs6923761 GLP-1 R polymorphism on body weight changes and metabolic parameters after 3 months of a hypocaloric diet.

DESIGN

A sample of 91 obese subjects was analyzed in a prospective way. The hypocaloric diet had 1,520 calories per day; 52 % of carbohydrates, 25 % of lipids and 23 % of proteins. Distribution of fats was: 50.7 % of monounsaturated fats, 38.5 % of saturated fats and 11.8 % of polyunsaturated fats.

RESULTS

In both genotype groups (GG vs. GA + AA), weight, body mass index, fat mass, waist circumference, systolic blood pressure, total cholesterol, LDL cholesterol, leptin, insulin and HOMA levels decreased. No statistical differences were detected in these changes between genotypes. In wild group (GG genotype) (pretreatment and posttreatment), BMI, weight, fat mass, waist circumference and triglyceride levels were higher than (GA + AA) group.

CONCLUSION

Our data showed better anthropometric parameters and triglyceride levels in obese subjects with the mutant allele (A) of rs6923761 GLP-1R polymorphism. A lack of association of this polymorphism with weight loss or biochemical changes after a hypocaloric diet was observed.

Non-rhinovirus enteroviruses associated with respiratory infections in Peru (2005-2010)

Background

Enteroviruses (EVs) are a common cause of respiratory tract infections and are classified into seven species (EVA-D and rhinoviruses [RHVs] A-C) with more than 200 different serotypes. Little is known about the role of non-RHV EVs in respiratory infections in South America. The aim of this study was to describe the epidemiology of non-RHV EVs detected in patients with influenza-like illness enrolled in a passive surveillance network in Peru.

Methods

Throat swabs and epidemiological data were collected from participants after obtaining verbal consent. Viral isolation was performed in cell culture and identified by immunofluorescence assay. Serotype identification of EV isolates was performed using commercial monoclonal antibodies. Identification of non-serotypeable isolations was carried out by reverse transcriptase-PCR, followed by sequencing.

Results

Between 2005 and 2010, 24,239 samples were analyzed, and 9,973 (41.1%) possessed at least one respiratory virus. EVs were found in 175 samples (0.7%). Our results revealed a clear predominance of EVB species, 90.9% (159/175). No EVDs were isolated. The mean and median ages of EV-positive subjects were 9.1 and 4.0 years, respectively, much younger than the population sampled, 17.6 and 12.0 years. Sixteen serotypes were identified, four EVA, 11 EVB, and one EVC species. The most common serotypes were coxsackievirus B1, coxsackievirus B2, coxsackievirus B5, and coxsackievirus B3.

Conclusion

This study provides data about the serotypes of EVs circulating in Peru and sets the need for further studies.

Detection of emerging contaminants (UV filters, UV stabilizers and musks) in marine mussels from Portuguese coast by QuEChERS extraction and GC-MS/MS

The UV filters and musk fragrances have come into focus because these compounds are contained and increasingly used not only in sunscreen products but also in many products of daily use, such as cosmetics, skin creams, plastics or varnish. In view of this, the main objective of the present work was to develop and validate a method for the determination of three UV filters, two UV stabilizers and four musks in mussel samples (Mytilus galloprovincialis). The procedure combined a QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) extraction method with an analysis by gas chromatography-tandem mass spectrometry (GC-MS/MS). The methodology allowed the determination of target analytes at trace concentration levels (ng/g), with mean recoveries ranging from 91 to 112%. A monitoring study was conducted in four beaches in the Portuguese coast which are impacted by recreational activities and outflow of treated waste water effluents in rivers. The results are used to assess the occurrence of UV filters in comparison with UV stabilizers and musk fragrances which indicate other activities than bathing.

A selective α2 B adrenoceptor agonist (A-1262543) and duloxetine modulate nociceptive neurones in the medial prefrontal cortex, but not in the spinal cord of neuropathic rats

BACKGROUND

The noradrenergic system contributes to pain modulation, but the roles of its specific adrenoceptors are still being defined. We have identified a novel, potent (rat EC50  = 4.3 nM) and selective α2B receptor agonist, A-1262543, to further explore this adrenoceptor subtype's contribution to pathological nociception.

METHODS

Systemic administration of A-1262543 (1-10 mg/kg, intraperitoneal) dose-dependently attenuated mechanical allodynia in animals with a spinal nerve ligation injury. To further explore its mechanism of action, the activity of nociceptive neurones in the spinal cord and medial prefrontal cortex (mPFC) were examined after injection of 3 mg/kg of A-1262543 (intravenous, i.v.). These effects were compared with duloxetine (3 mg/kg, i.v.), a dual noradrenaline (NA) and serotonin (5-HT) reuptake inhibitor.

RESULTS

Systemic administration of A-1262543 or duloxetine did not alter the spontaneous or evoked firing of spinal wide dynamic range and nociceptive-specific neurones in the neuropathic rats, indicating that neither compound engaged spinal, peripheral or descending pathways. In contrast to the lack of effect on spinal neurones, both A-1262543 and duloxetine reduced the evoked and spontaneous firing of 'pain-responsive' (PR) neurones in the mPFC. Duloxetine, but not A-1262543, also inhibited the firing of pain non-responsive (nPR) neurones in the mPFC probably reflecting duloxetine's contribution to modulating non-pain endpoints.

CONCLUSIONS

These data highlight that activation of the α2B adrenoceptor as well as inhibiting NA and 5-HT reuptake can result in modulating the ascending nociceptive system, and in particular, dampening the firing of PR neurones in the mPFC.

Prediction of pregnancy viability in bovine in vitro-produced embryos and recipient plasma with Fourier transform infrared spectroscopy

We analyzed embryo culture medium (CM) and recipient blood plasma using Fourier transform infrared (FTIR) metabolomics to predict pregnancy outcome. Individually cultured, in vitro-produced (IVP) blastocysts were transferred to recipients as fresh and vitrified-warmed. Spent CM and plasma samples were evaluated using FTIR. The discrimination capability of the classifiers was assessed for accuracy, sensitivity (pregnancy), specificity (nonpregnancy), and area under the receiver operator characteristic curve (AUC). Within all IVP fresh embryos (birth rate=52%), high AUC were obtained at birth, especially with expanded blastocysts (CM: 0.80±0.053; plasma: 0.89±0.034). The AUC of vitrified IVP embryos (birth rate = 31%) were 0.607±0.038 (CM, expanded blastocysts) and 0.672±0.023 (plasma, all stages). Recipient plasma generally predicted pregnancy outcome better than did embryo CM. Embryos and recipients with improved pregnancy viability were identified, which could increase the economic benefit to the breeding industry.

[Bronchioloalveolar carcinoma: an exceptional cause of diffuse lung disease in a patient with acute myeloid leukemia]

INTRODUCTION

Bronchiolo-alveolar carcinoma is a primary pulmonary adenocarcinoma developing in the terminal respiratory unit.

CASE REPORT

An 84-year-old non-smoker woman with a history of untreated acute myeloid leukaemia was referred to the intensive care unit for pneumonia and acute respiratory failure. The patient reported dyspnoea and a productive cough for 3 months, treated by antibiotics and steroids without improvement. Thoracic CT-scan showed alveolar condensations and multiple nodular lesions. All microbiological samples were negative and the evolution was fatal within 72 hours despite empirical antibiotic therapy and noninvasive ventilation. Post-mortem lung biopsies gave a diagnosis of mucinous and non-mucinous bronchiolo-alveolar carcinoma with typical lepidic growth pattern of tumor cells and discrete septal thickening but no fibrosis, inflammation or local invasion.

CONCLUSION

Bronchiolo-alveolar carcinoma is an alternative diagnosis in alveolar condensations associated with pulmonary nodules even in a patient with immunosupression. Early diagnosis allows effective treatment in some cases.

[Assessment of endothelial function in autoimmune diseases]

Numerous autoimmune-inflammatory rheumatic diseases have been associated with accelerated atherosclerosis or other types of vasculopathy leading to an increase in cardiovascular disease incidence. In addition to traditional cardiovascular risk factors, endothelial dysfunction is an important early event in the pathogenesis of atherosclerosis, contributing to plaque initiation and progression. Endothelial dysfunction is characterized by a shift of the actions of the endothelium toward reduced vasodilation, a proinflammatory and a proadhesive state, and prothrombic properties. Therefore, assessment of endothelial dysfunction targets this vascular phenotype using several biological markers as indicators of endothelial dysfunction. Measurements of soluble adhesion molecules (ICAM-1, VCAM-1, E-selectin), pro-thrombotic factors (thrombomodulin, von Willebrand factor, plasminogen activator inhibitor-1) and inflammatory cytokines are most often performed. Regarding the functional assessment of the endothelium, the flow-mediated dilatation of conduit arteries is a non-invasive method widely used in pathophysiological and interventional studies. In this review, we will briefly review the most relevant information upon endothelial dysfunction mechanisms and explorations. We will summarize the similarities and differences in the biological and functional assessments of the endothelium in different autoimmune diseases.