Diet and Metabolism in the Evolution of Asthma and Obesity

Obesity and Asthma: Implementing a Treatable Trait Care Model

Recognition of obesity as a treatable trait of asthma, impacting its development, clinical presentation and management, is gaining widespread acceptance. Obesity is a significant risk factor and disease modifier for asthma, complicating treatment. Epidemiological evidence highlights that obese asthma correlates with poorer disease control, increased severity and persistence, compromised lung function and reduced quality of life. Various mechanisms contribute to the physiological and clinical complexities observed in individuals with obesity and asthma. These encompass different immune responses, including Type IVb, where T helper 2 cells are pivotal and driven by cytokines like interleukins 4, 5, 9 and 13, and Type IVc, characterised by T helper 17 cells and Type 3 innate lymphoid cells producing interleukin 17, which recruits neutrophils. Additionally, Type V involves immune response dysregulation with significant activation of T helper 1, 2 and 17 responses. Finally, Type VI is recognised as metabolic-induced immune dysregulation associated with obesity. Body mass index (BMI) stands out as a biomarker of a treatable trait in asthma, readily identifiable and targetable, with significant implications for disease management. There exists a notable gap in treatment options for individuals with obese asthma, where asthma management guidelines lack specificity. For example, there is currently no evidence supporting the use of incretin mimetics to improve asthma outcomes in asthmatic individuals without Type 2 diabetes mellitus (T2DM). In this review, we advocate for integrating BMI into asthma care models by establishing clear target BMI goals, promoting sustainable weight loss via healthy dietary choices and physical activity and implementing regular reassessment and referral as necessary.

Physical Health-Related Quality of Life in Relation to Mediterranean Diet Adherence in a Sample of Greek Asthma Patients: A Pilot Study

The role of nutrition in the management of asthma in obese patients is of increasing interest due to their limited response to inhaled corticosteroids. Some studies note that through diet and lifestyle, there can be an improvement in asthma control. The aim of the present study was to investigate the adherence to the Mediterranean Diet and its association with asthma severity and quality of life in patients with bronchial asthma. This is a cross-sectional study of 85 patients (70.6% female), with a mean age of 57 years, from the General University Hospital of Larissa and, more specifically, patients of the outpatient asthma clinic. Data were collected with the use of specific questionnaires. In relation to BMI, 12.9% of participants were of a normal weight, 45.9% were overweight, 25.9% were obese level I, 5.9% were obese level II, and 9.4% were in the morbidly obese range. Based on the Med Diet Score (ranging from 21 to 35), most participants (85.9%) reported moderate adherence to the Mediterranean Diet. Further analysis examined the correlations of the PCS-12 score with the frequency of consumption of each of the 11 food categories, as well as all demographic and health behavior variables. The ranked correlations indicated a significant relationship between PCS-12 score and Med Diet adherence and the consumption of alcoholic beverages (r = 0.437, p < 0.05), in accordance with the Mediterranean Diet suggestions, as well as a negative relationship with BMI score (r = -0.454, p < 0.010). Moreover, significant correlations were also present between the physical quality of life and AQLQ score and work type, as well as gender, age, and marital status. The results of our study showed a high rate of obesity in patients with asthma at the General University Hospital of Larissa and moderate adherence to the Mediterranean Diet. Increased BMI and alcoholic beverage consumption in asthma patients were significant predictors of lower physical health-related quality of life. In conclusion, personal and society-level interventions are required to effectively address obesity and poor diet in patients with asthma.

Obesity and Selected Allergic and Immunological Diseases-Etiopathogenesis, Course and Management

Obesity is a global problem. It affects every age group and is associated with many negative health effects. As an example, there is a relationship between obesity and allergic and immunological diseases, such as asthma, psoriasis, food allergies, allergic rhinitis and atopic dermatitis. Obesity undeniably affects their development. In addition, it causes adverse changes in the course and response to therapy in relation to patients without excessive body weight. The treatment of diseases associated with obesity is difficult; drugs are less effective and must be used in higher doses, and their use in patients with obesity is often associated with higher risks. The main form of treatment of all obesity-related diseases is a change in eating habits and increased physical activity, which leads to a decrease in body fat mass. The positive effect of reducing BMI has been confirmed in many independent studies. This paper reviews various types of research documents published since 2019. It aims to systematize the latest knowledge and highlight the need for further research for effective and sustainable treatment options for obesity, its complications and obesity-related diseases.

[Diagnosis and treatment of asthma: a guideline for respiratory specialists 2023 - published by the German Respiratory Society (DGP) e. V.]

The management of asthma has fundamentally changed during the past decades. The present guideline for the diagnosis and treatment of asthma was developed for respiratory specialists who need detailed and evidence-based information on the new diagnostic and therapeutic options in asthma. The guideline shows the new role of biomarkers, especially blood eosinophils and fractional exhaled NO (FeNO), in diagnostic algorithms of asthma. Of note, this guideline is the first worldwide to announce symptom prevention and asthma remission as the ultimate goals of asthma treatment, which can be achieved by using individually tailored, disease-modifying anti-asthmatic drugs such as inhaled steroids, allergen immunotherapy or biologics. In addition, the central role of the treatment of comorbidities is emphasized. Finally, the document addresses several challenges in asthma management, including asthma treatment during pregnancy, treatment of severe asthma or the diagnosis and treatment of work-related asthma.

Alleviation of Asthma Symptoms After Ketogenic Diet: A Case Report

Asthma is a chronic disease that affects the quality of life of patients, and asthma exacerbations are often a reason for hospitalization and activity limitations. Obesity has been linked to asthma as a risk and exacerbating factor. Evidence suggests that weight reduction has a positive effect on asthma control. However, there is also debate on the role of the ketogenic diet in asthma control. Here we present a case of asthma who reported markedly improved asthma after starting a ketogenic diet in the absence of any other lifestyle change. Over the four months on the ketogenic diet, the patient reported losing 20 kg of weight, reduction in blood pressure (without antihypertensives), and complete alleviation of asthma symptoms. This case report is important as the control of asthma after a ketogenic diet is not studied well in humans and therefore needs to be studied extensively.

Female-biased association of NOS2-c.1823C>T (rs2297518) with co-susceptibility to metabolic syndrome and asthma

The nitric oxide (NO) pathway contributes to the pathogeneses of metabolic syndrome (MetS) and asthma. NOS2 encodes inducible-NO synthase, which is an important enzyme of the pathway, and its variations could affect the risk of asthma and MetS and thereby co-susceptibility to them. This study aims to estimate the association of NOS2-c.1823C>T with risk of asthma, MetS, and asthma with MetS condition (ASMetS), and with asthma stages: intermittent, mild, moderate, and severe asthma. The study included asthmatics (n = 555), MetS (n = 334), and ASMetS cases (n = 232) and 351 controls, which were genotyped by the PCR-RFLP method. The T allele was significantly associated with an increased risk of asthma and MetS in the sample population and females. CT genotype and CT+TT model were significantly associated with increased risk of ASMetS in females. A significant association between CT genotype and increased risk of ASMetS in the sample population and females was found in ASMetS versus MetS. In the sample population and among females, the T allele was significantly associated with severe asthma. The rs2297518 single nucleotide polymorphism of NOS2 contributes to the risk of MetS, asthma, and co-susceptibility to them, and this contribution may be stronger in females compared to males.

The Relationship Between General and Abdominal Obesity, Nutrition and Respiratory Functions in Adult Asthmatics

Objective: Although obesity is known to have adverse effects on asthma, it is not fully known whether general or abdominal obesity affects asthma symptoms more. In this study, the effects of diet and general/abdominal obesity on respiratory functions were evaluated.Methods: A total of 204 adult asthmatic individuals participated in the study. Anthropometric measurements, respiratory functions, asthma control test (ACT) scores, and 24-hour food consumption were recorded. The results were compared according to body mass index (BMI), waist circumference (WC), and waist-hip ratio (WHR) classification.Results: FEV₁, FVC, MEF_25-75, MEF₅₀, and MEF₂₅ decreased with the increase in BMI, WC, and WHR. FEV₁ showed a negative linear relationship with BMI, WC and WHR and these results were more significant in WC and WHR than BMI. Similarly, the ACT score also showed a negative correlation with BMI (r = -0.372; p = 0.023), WC (r = -0.402; p = 0.001) and WHR (r = -0.387; p = 0.011), and the results were more significant in WC and WHR than BMI. Individuals whose WC (OR: 2.170 CI (1.325-3.182)) and WHR (OR: 2.119 CI (1.246-3.338)) were at risk had higher odds of uncontrolled asthma than those with normal WC and WHR. Each 100-kcal increase in total energy consumption increased the odds of uncontrolled asthma (OR: 1.125 CI (1.086-2.217)) (p < 0.05).Conclusions: The effects of WC and WHR, which are indicators of abdominal obesity, on respiratory functions and ACT score were found to be higher than BMI. Obese individuals should be referred to diet clinics to improve their asthma symptoms.

Microbiome, Metabolism, and Immunoregulation of Asthma: An American Thoracic Society and National Institute of Allergy and Infectious Diseases Workshop Report

This report presents the proceedings from a workshop titled "Microbiome, Metabolism and Immunoregulation of Asthma" that was held virtually May 13 and 14, 2021. The workshop was jointly sponsored by the American Thoracic Society (Assembly on Allergy, Immunology, and Inflammation) and the National Institute of Allergy and Infectious Diseases. It convened an interdisciplinary group of experts with backgrounds in asthma immunology, microbiome science, metabolomics, computational biology, and translational pulmonary research. The main purpose was to identify key scientific gaps and needs to further advance research on microbial and metabolic mechanisms that may contribute to variable immune responses and disease heterogeneity in asthma. Discussions were structured around several topics, including 1) immune and microbial mechanisms of asthma pathogenesis in murine models, 2) the role of microbes in pediatric asthma exacerbations, 3) dysregulated metabolic pathways in asthma associated with obesity, 4) metabolism effects on macrophage function in adipose tissue and the lungs, 5) computational approaches to dissect microbiome-metabolite links, and 6) potential confounders of microbiome-disease associations in human studies. This report summarizes the major points of discussion, which included identification of specific knowledge gaps, challenges, and suggested directions for future research. These include questions surrounding mechanisms by which microbiota and metabolites shape host health versus an allergic or asthmatic state; direct and indirect influences of other biological factors, exposures, and comorbidities on these interactions; and ongoing technical and analytical gaps for clinical translation.

High density lipoprotein inhibited group II innate lymphoid cells proliferation and function in allergic rhinitis

Background

More and more studies had suggested that dyslipidemia was closely related to allergic diseases. High density lipoprotein (HDL) often plays anti-inflammatory and anti-oxidative roles by suppressing immune cell chemotaxis and activation. We aimed to explore the role of HDL in the regulation of group II innate lymphoid cells (ILC2) in allergic rhinitis (AR).

Methods

The blood lipid levels and their correlation with symptom scores of 20 AR subjects and 20 controls were analyzed. Purified ILC2 were stimulated by HDL and cytokines production were examined by enzyme-linked immunosorbent assay (ELISA) and flow cytometry. The mRNA levels of GATA binding protein 3(GATA3) and retinoid-related orphan receptor α (RORα) expressed by ILC2 were detected using reverse transcription polymerase chain reaction (RT-PCR).

Results

HDL level was significantly lower in AR than controls and correlated with the symptom scores. The serum HDL levels were negatively related to the increased number of ILC2, IL-5⁺ ILC2, and IL-13⁺ ILC2 in AR patients. HDL decreased the number of ILC2 and type II cytokines levels significantly by inhibiting expression of GATA3 and RORα.

Conclusions

Our data provide preliminary evidence that HDL may play a negative role in ILC2 inflammation in AR, suggesting that HDL may serve as promising treatment target in AR.

Metabolomic Associations of Asthma in the Hispanic Community Health Study/Study of Latinos

Asthma disproportionally affects Hispanic and/or Latino backgrounds; however, the relation between circulating metabolites and asthma remains unclear. We conducted a cross-sectional study associating 640 individual serum metabolites, as well as twelve metabolite modules, with asthma in 3347 Hispanic/Latino background participants (514 asthmatics, 15.36%) from the Hispanic/Latino Community Health Study/Study of Latinos. Using survey logistic regression, per standard deviation (SD) increase in 1-arachidonoyl-GPA (20:4) was significantly associated with 32% high odds of asthma after accounting for clinical risk factors (p = 6.27 × 10−5), and per SD of the green module, constructed using weighted gene co-expression network, was suggestively associated with 25% high odds of asthma (p = 0.006). In the stratified analyses by sex and Hispanic and/or Latino backgrounds, the effect of 1-arachidonoyl-GPA (20:4) and the green module was predominantly observed in women (OR = 1.24 and 1.37, p < 0.001) and people of Cuban and Puerto-Rican backgrounds (OR = 1.25 and 1.27, p < 0.01). Mutations in Fatty Acid Desaturase 2 (FADS2) affected the levels of 1-arachidonoyl-GPA (20:4), and Mendelian Randomization analyses revealed that high genetically regulated 1-arachidonoyl-GPA (20:4) levels were associated with increased odds of asthma (p < 0.001). The findings reinforce a molecular basis for asthma etiology, and the potential causal effect of 1-arachidonoyl-GPA (20:4) on asthma provides an opportunity for future intervention.

Repression of the expression of proinflammatory genes by mitochondrial transcription factor A is linked to its alternative splicing regulation in human lung epithelial cells

Background

Mitochondrial transcription factor A (TFAM) is associated with a number of neurodegenerative diseases and also with asthma. TFAM deficiency-induced mitochondrial DNA stress primes the antiviral innate immune response in mouse embryonic fibroblasts. However, the role of TFAM in asthma related inflammation remains obscure. The purpose of this study was to investigate the regulatory mechanism of TFAM in asthma.

Results

In this study, we overexpressed TFAM in human lung epithelial cells (A549), then obtained the TFAM-regulated transcriptome by Illumina sequencing technology. Transcriptome analysis revealed that TFAM overexpression down-regulated and up-regulated the expression of 642 and 169 differentially expressed genes (DEGs), respectively. The TFAM-repressed genes were strongly enriched in cytokine-mediated signaling pathway, type I interferon- and INF-γ-mediated signaling pathways, and viral response pathways. We also revealed that 2563 alternative splicing events in 1796 alternative splicing genes (ASGs) were de-regulated upon TFAM overexpression. These TFAM-responding ASGs were enriched in DNA repair, nerve growth factor receptor signaling pathway, and also transcription regulation. Further analysis revealed that the promoters of TFAM-repressed DEGs were enriched by DNA binding motifs of transcription factors whose alternative splicing was regulated by TFAM.

Conclusions

These findings suggest that TFAM regulates not only immune response gene expression in human lung epithelial cells, but also pre-mRNA alternative splicing which may mediate transcriptional regulation; this TFAM-centered gene regulation network could be targeted in developing therapies against various diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12865-021-00464-2.

Dietary patterns in patients with asthma and their relationship with asthma-related emergency room visits: NHANES 2005-2016

RATIONALE

Extensive interdependencies exist between dietary intake, metabolic dysregulation, and asthma; however, the dietary pattern in adults with asthma remains unknown.

OBJECTIVES

To evaluate the association between dietary patterns and asthma ER visits and explore the effect of the interaction between race and diet on asthma.

METHODS

Using NHANES data, we compared dietary patterns between adults with asthma with and without asthma-related emergency room (ER) visits in the previous year, and between subjects of different races. The 2015 Healthy Eating Index (HEI-2015) was used to assess alignment between dietary patterns and the 2015-2020 Dietary Guideline for Americans.

RESULTS

Among 1681 individuals included in the study, 193 reported asthma-related ER visit. Patients with asthma had low fruit and vegetable intake, and a low mean (SE) HEI-2015 score [52.6 (0.53)]. Individuals with asthma-related ER visits had lower vegetable consumption compared to those without (median 0.61 vs. 0.85 cup equivalents). Furthermore, non-Hispanic Blacks (NHB) reported lower amount of vegetable (median cup equivalent 0.58 vs. 0.89) and fruit intake (0.17 vs. 0.39) and had a lower HEI-2015 score (49.9 vs. 52.9) comparing to non-Hispanic Whites. No association was discovered between dietary patterns and ER visits in multivariable analysis, or significant interactions between diet and race in predicting the need for ER visits.

CONCLUSIONS

Dietary patterns in adult with current asthma are frequently misaligned with current dietary guidelines. Patients with asthma-related ER visits and of NHB race had lower vegetable consumption; however, the associations disappeared in multivariable analysis. The impact of diet on asthma is not straightforward and deserves further investigation.

Supplemental data for this article is available online at at www.tandfonline.com/ijas.

Nitroalkene fatty acids modulate bile acid metabolism and lung function in obese asthma

Bile acid profiles are altered in obese individuals with asthma. Thus, we sought to better understand how obesity-related systemic changes contribute to lung pathophysiology. We also test the therapeutic potential of nitro-oleic acid (NO₂-OA), a regulator of metabolic and inflammatory signaling pathways, to mitigate allergen and obesity-induced lung function decline in a murine model of asthma. Bile acids were measured in the plasma of healthy subjects and individuals with asthma and serum and lung tissue of mice with and without allergic airway disease (AAD). Lung function, indices of inflammation and hepatic bile acid enzyme expression were measured in obese mice with house dust mite-induced AAD treated with vehicle or NO₂-OA. Serum levels of glycocholic acid and glycoursodeoxycholic acid clinically correlate with body mass index and airway hyperreactivity whereas murine levels of β-muricholic acid and tauro-β-muricholic acid were significantly increased and positively correlated with impaired lung function in obese mice with AAD. NO₂-OA reduced murine bile acid levels by modulating hepatic expression of bile acid synthesis enzymes, with a concomitant reduction in small airway resistance and tissue elastance. Bile acids correlate to body mass index and lung function decline and the signaling actions of nitroalkenes can limit AAD by modulating bile acid metabolism, revealing a potential pharmacologic approach to improving the current standard of care.

Lipid Nutrition in Asthma

Asthma is a heterogeneous pulmonary disease that has constantly increased in prevalence over the past several decades. Primary symptoms include airway constriction, airway hyperresponsiveness, and airway remodeling with additional symptoms such as shortness of breath, wheezing, and difficulty breathing. Allergic asthma involves chronic inflammation of the lungs, and the rise in its yearly diagnosis is potentially associated with the increased global consumption of foods similar to the western diet. Thus, there is growing interest into the link between diet and asthma symptoms, with mounting evidence for an important modulatory role for dietary lipids. Lipids can act as biological mediators in both a proinflammatory and proresolution capacity. Fatty acids play key roles in signaling and in the production of mediators in the allergic and inflammatory pathways. The western diet leads to a disproportionate ω-6:ω-3 ratio, with drastically increased ω-6 levels. To counteract this, consumption of fish and fish oil and the use of dietary oils with anti-inflammatory properties such as olive and sesame oil can increase ω-3 and decrease ω-6 levels. Increasing vitamin intake, lowering LDL cholesterol levels, and limiting consumption of oxidized lipids can help reduce the risk of asthma and the exacerbation of asthmatic symptoms. These dietary changes can be achieved by increasing intake of fruits, vegetables, nuts, oily fish, seeds, animal-related foods (eggs, liver), cheeses, grains, oats, and seeds, and decreasing consumption of fried foods (especially fried in reused oils), fast foods, and heavily processed foods.

Gestational and Postpartum Weight Trajectories Among Women With and Without Asthma

Asthma leads to increased weight gain in nonpregnant populations, but studies have not examined this association within the context of pregnancy. The association between asthma and perinatal weight trajectories was examined in the Breathe-Wellbeing, Environment, Lifestyle, and Lung Function Study (2015-2019). Multilevel linear spline models were adjusted for age, race/ethnicity, income, marital status, education, cigarette smoking, parity, study site, and prepregnancy body mass index were used to examine differences in perinatal weight trajectories between women with (n = 299) and without (n = 101) asthma. Secondary analyses were conducted to assess whether associations differed by asthma phenotypes. At 40 weeks' gestation, women with asthma gained 16.2 kg (95% confidence interval (CI): 14.6, 17.7) and women without asthma gained 13.1 kg (95% CI: 10.9, 15.4). At 3 months postpartum, women with asthma retained 10.4 kg (95% CI: 8.9, 11.9) and women without asthma retained 8.0 kg (95% CI: 5.9, 10.2). Among women with asthma, exercise-induced asthma and step 3 asthma medications were associated with excess gestational weight gain. These study findings suggest women with asthma gain and retain more weight during pregnancy and postpartum than do women without asthma.

Diabetes Mellitus Is Associated with Worse Outcome in Patients Hospitalized for Asthma

BACKGROUND

Asthma is a prevalent disease with a high economic cost. More than 50% of its direct cost relates to asthma hospitalizations. Diabetes mellitus (DM) is a significant comorbidity in asthmatic patients, yet its impact on asthma-related hospitalizations is unknown.

OBJECTIVE

To compare the outcome of asthma-related hospitalizations in patients with and without DM.

METHODS

Using Healthcare Cost and Utilization Project Nationwide Readmissions Database, we analyzed data of all adults with index admission for asthma and with no other chronic pulmonary conditions, and compared outcomes between patients with and without DM. Weighted regression analysis was used to determine the impact of DM on hospitalization outcomes. All multivariate regression models were adjusted for patient demographics, socioeconomic status, and chronic medical comorbidities.

RESULTS

A total of 717,200 asthmatic patients were included, with 202,489 (28.3%) having DM. Diabetic patients were older and had more comorbidities. When hospitalized for asthma, diabetic patients had increased hospital length of stay, cost, and risk for 30-day all-cause and asthma-related readmission. They also had a higher risk for developing nonrespiratory complications during their hospital stay compared with nondiabetic patients. The risk of mortality was similar between the 2 groups.

CONCLUSIONS

Patients hospitalized for asthma with coexisting DM had increased hospital length of stay, cost, and risk for readmission. Interventions are urgently needed to reduce the risk for hospital admission and readmission in patients with coexisting DM and asthma. These interventions would have profound economic and societal impact.

COVID-19 and Pediatric Asthma: Clinical and Management Challenges

Asthma is the most frequent chronic condition in childhood and a current concern exists about asthma in the pediatric population and its risk for severe SARS-CoV-2 infection. Although all ages can be affected, SARS-CoV-2 infection has lower clinical impact on children and adolescents than on adults. Fever, cough and shortness of breath are the most common symptoms and signs in children; wheezing has not been frequently reported. Published studies suggest that children with asthma do not appear to be disproportionately more affected by COVID-19. This hypothesis raises two issues: is asthma (and/or atopy) an independent protective factor for COVID-19? If yes, why? Explanations for this could include the lower IFN-α production, protective role of eosinophils in the airway, and antiviral and immunomodulatory proprieties of inhaled steroids. Additionally, recent evidence supports that allergic sensitization is inversely related to ACE2 expression. Obesity is a known risk factor for COVID-19 in adults. However, in the childhood asthma–obesity phenotype, the classic atopic Th2 pattern seems to predominate, which could hypothetically be a protective factor for severe SARS-CoV-2 infection in children with both conditions. Finally, the return to school activities raises concerns, as asymptomatic children could act as vectors for the spread of the disease. Although this is still a controversial topic, the identification and management of asymptomatic children is an important approach during the SARS-CoV-2 epidemic. Focus on asthma control, risk stratification, and medication adherence will be essential to allow children with asthma to return safely to school.

A prospective controlled study on Ramadan fasting in the healthy young males in summer in Germany: effect on cytokines

SHORT COMMUNICATION

During the Ramadan fasting (RF) month, participants restrict some activities during day time, particularly consumption of food and beverages. In Germany, Muslims fast about 18-19 h a day when Ramadan falls in the summer. This longer period of restriction could lead to the changes of the body physiology, anthropometric parameters and biological mediators.

OBJECTIVES

This study aimed to determine the effect of Ramadan fasting on cytokines (Interleukin (IL)-1β. IL-6, IL-8, IL-10, IL-12, tumor necrosis factor (TNF)-α) during RF in Germany. Correlations of cytokines with anthropometric parameters were also determined.

METHODS

Fifty healthy adult males were recruited and divided into two equal groups: fasting group (FG) and non-fasting group (NFG). FG was evaluated at T1: one week before, T2: mid-, T3: last days of, and T4: one week after Ramadan. The NFG were evaluated only at T1 and T3.

RESULTS

In FG significant alterations of IL-1β was observed. Insignificant differences were found between the FG and NFG at T1 and T3 concerning the measured cytokines. Circulating IL-1β increased significantly from T2 to T4 and from T3 to T4. At T3, TNF-α was correlated significantly with anthropometric parameters such as the body weight, the skeletal muscle mass and the fat free mass, whilst IL-12 was correlated significantly with the skeletal muscle mass, the fat free mass and the body water mass at T4.

CONCLUSIONS

Significant Alterations of IL-1β during RF in FG were observed. Anthropometric parameters correlate with TNF-α and IL-12 levels during at T3 and T4, respectively.

RELATIONS BETWEEN ASTHMA AND OBESITY: AN ANALYSIS OF MULTIPLE FACTORS

OBJECTIVE

Asthma and obesity are prevalent and interrelated diseases. In the pediatric population, the effect of systemic inflammation associated to obesity, leading to inflammation of the airways, is currently controversial. Our aim was to compare inflammatory, clinical and spirometric patterns between children with asthma and obesity and those within the normal weight status range.

METHODS

A total of 79 boys and girls from 6 to 10 years old were selected and divided into four groups: obese asthmatics, non-obese asthmatics, obese non-asthmatics, and non-obese non-asthmatics. In addition to collecting clinical and anthropometric data, all children underwent spirometry and skin prick tests for inhalant allergens. Blood samples for measurement of cytokines and adipokines were also collected.

RESULTS

Obese asthmatics had significantly worse control of asthma than non-obese asthmatics (OR 4.9; 95%CI 1.1‒22.1), regardless of sex, physical activity and atopy. No differences in spirometry, Th1 and Th2 cytokines and adipokines levels were observed among the four groups. The prick tests were positive in 81.8 and 80% of non-obese asthmatics and obese asthmatics, respectively.

CONCLUSIONS

The degree of control of asthma was significantly lower in the obese group, regardless of the findings of no differences in spirometry. Extra-pulmonary factors could be responsible for this symptomatic profile. High positivity of skin test in both groups, which is considered a good marker of atopy, shows a preponderant atopic component in the genesis of asthma, both in children with obesity and in those within the normal weight status.

Androgen and Androgen Receptors as Regulators of Monocyte and Macrophage Biology in the Healthy and Diseased Lung

Androgens, the predominant male sex hormones, drive the development and maintenance of male characteristics by binding to androgen receptor (AR). As androgens are systemically distributed throughout the whole organism, they affect many tissues and cell types in addition to those in male sexual organs. It is now clear that the immune system is a target of androgen action. In the lungs, many immune cells express ARs and are responsive to androgens. In this review, we describe the effects of androgens and ARs on lung myeloid immune cells-monocytes and macrophages-as they relate to health and disease. In particular, we highlight the effect of androgens on lung diseases, such as asthma, chronic obstructive pulmonary disease and lung fibrosis. We also discuss the therapeutic use of androgens and how circulating androgens correlate with lung disease. In addition to human studies, we also discuss how mouse models have helped to uncover the effect of androgens on monocytes and macrophages in lung disease. Although the role of estrogen and other female hormones has been broadly analyzed in the literature, we focus on the new perspectives of androgens as modulators of the immune system that target myeloid cells during lung inflammation.

Metabolic Dysfunction and Asthma: Current Perspectives

The increasing knowledge of the mechanisms involved in metabolism is shifting the paradigms by which the pathophysiology of many pulmonary diseases is understood. Metabolic dysfunction is recognized in obesity-associated asthma, but other metabolic conditions have been shown to be independently related to asthma. Novel insights have also recently been brought by metabolomics in this filed. The purpose of this review is to discuss current perspectives regarding metabolic dysfunction in asthma, from obesity-related asthma to other metabolic conditions and the role of current pharmacological therapeutic strategies and lifestyle interventions. Obesity is a well-recognized risk factor for asthma across the lifespan, which is generally associated with poorer response to current available treatments, rendering a more severe, refractory disease status. Besides the epidemiological and clinical link, untargeted metabolomics studies have recently supported the obesity-associated asthma phenotype at the molecular level. Not only obesity-related, but also other aspects of metabolic dysregulation can be independently linked to asthma. These include hyperinsulinemia, dyslipidemia and hypertension, which need to be taken into account, even in the non-obese patient. Untargeted metabolomics studies have further highlighted several other metabolic pathways that can be altered in asthma, namely regarding oxidative stress and systemic inflammation, and also suggesting the importance of microbiota in asthma pathogenesis. Considering the reduced response to corticosteroids, other pharmacologic treatments have been shown to be effective regardless of body mass index. Non-pharmacologic treatments (namely weight reduction and dietary changes) may bring substantial benefit to the asthmatic patient. Taken together, this evidence points towards the need to improve our knowledge in this filed and, in particular, to address the influence of environmental factors in metabolic dysfunction and asthma development. Personalized medicine is definitely needed to optimize treatment, including a holistic view of the asthmatic patient in order to set accurate pharmacologic therapy together with dietary, physical exercise and lifestyle interventions.

Synergistic Effect of WTC-Particulate Matter and Lysophosphatidic Acid Exposure and the Role of RAGE: In-Vitro and Translational Assessment

World Trade Center particulate matter (WTC-PM)-exposed firefighters with metabolic syndrome (MetSyn) have a higher risk of WTC lung injury (WTC-LI). Since macrophages are crucial innate pulmonary mediators, we investigated WTC-PM/lysophosphatidic acid (LPA) co-exposure in macrophages. LPA, a low-density lipoprotein metabolite, is a ligand of the advanced glycation end-products receptor (AGER or RAGE). LPA and RAGE are biomarkers of WTC-LI. Human and murine macrophages were exposed to WTC-PM, and/or LPA, and compared to controls. Supernatants were assessed for cytokines/chemokines; cell lysate immunoblots were assessed for signaling intermediates after 24 h. To explore the translatability of our in-vitro findings, we assessed serum cytokines/chemokines and metabolites of symptomatic, never-smoking WTC-exposed firefighters. Agglomerative hierarchical clustering identified phenotypes of WTC-PM-induced inflammation. WTC-PM induced GM-CSF, IL-8, IL-10, and MCP-1 in THP-1-derived macrophages and induced IL-1α, IL-10, TNF-α, and NF-κB in RAW264.7 murine macrophage-like cells. Co-exposure induced synergistic elaboration of IL-10 and MCP-1 in THP-1-derived macrophages. Similarly, co-exposure synergistically induced IL-10 in murine macrophages. Synergistic effects were seen in the context of a downregulation of NF-κB, p-Akt, -STAT3, and -STAT5b. RAGE expression after co-exposure increased in murine macrophages compared to controls. In our integrated analysis, the human cytokine/chemokine biomarker profile of WTC-LI was associated with discriminatory metabolites (fatty acids, sphingolipids, and amino acids). LPA synergistically elaborated WTC-PM’s inflammatory effects in vitro and was partly RAGE-mediated. Further research will focus on the intersection of MetSyn/PM exposure.

Sex differences in the influence of obesity on a murine model of allergic lung inflammation

BACKGROUND

Despite the overwhelming evidence showing the influence of sex or obesity in the development of respiratory diseases in humans and animals, the mechanisms by which these combined two factors influence allergic asthma are not well understood.

OBJECTIVE

We have investigated the interaction between sex and weight gain in an experimental model of lung allergic inflammation induced by chicken egg ovalbumin (OVA) in mice.

METHODS

Animals were fed a high-fat diet for 8 weeks and then sensitized and challenged with OVA.

RESULTS

Our results demonstrate that in comparison with males, high-fat diet (HFD) allergic female mice exhibit a reduction in the number of leucocytes in the lung lumen when challenged with OVA and, in contrast, an accumulation of these cells in the lung tissue. In addition, we also observed that allergic HFD female mice presented a robust lung remodelling in comparison with HFD males, evidenced by higher deposition of collagen in the airways and TGF-β in lung fluid. Measuring epithelial adhesion molecule expression, we observed that female mice presented a significantly lower expression of CD103 than males in BAL cells, regardless of the diet. Similarly, HFD female mice express lower levels of EpCAM in lung tissue in comparison with males and lean females. Levels of A20/TNFAIP3 expression in lung tissue demonstrated that HFD female mice express lower levels of these regulatory factors than all the other groups. However, this reduction was not accompanied by an increase in activated NF-κB.

CONCLUSIONS

Our results present evidence that the interaction between sex and weight gain alters the progression of allergic asthma in mice with females developing airway remodelling at a much earlier stage than males.

CLINICAL RELEVANCE

These data may contribute to a better understanding of the clinical differences in the development and severity of allergic asthma observed between men and women of reproductive age.

Sex, obesity, diabetes, and exposure to particulate matter among patients with severe asthma: Scientific insights from a comparative analysis of open clinical data sources during a five-day hackathon

This special communication describes activities, products, and lessons learned from a recent hackathon that was funded by the National Center for Advancing Translational Sciences via the Biomedical Data Translator program ('Translator'). Specifically, Translator team members self-organized and worked together to conceptualize and execute, over a five-day period, a multi-institutional clinical research study that aimed to examine, using open clinical data sources, relationships between sex, obesity, diabetes, and exposure to airborne fine particulate matter among patients with severe asthma. The goal was to develop a proof of concept that this new model of collaboration and data sharing could effectively produce meaningful scientific results and generate new scientific hypotheses. Three Translator Clinical Knowledge Sources, each of which provides open access (via Application Programming Interfaces) to data derived from the electronic health record systems of major academic institutions, served as the source of study data. Jupyter Python notebooks, shared in GitHub repositories, were used to call the knowledge sources and analyze and integrate the results. The results replicated established or suspected relationships between sex, obesity, diabetes, exposure to airborne fine particulate matter, and severe asthma. In addition, the results demonstrated specific differences across the three Translator Clinical Knowledge Sources, suggesting cohort- and/or environment-specific factors related to the services themselves or the catchment area from which each service derives patient data. Collectively, this special communication demonstrates the power and utility of intense, team-oriented hackathons and offers general technical, organizational, and scientific lessons learned.

Asthma and Ultra-Processed Food

In the Decade of Nutrition, food must be reconsidered. The main objective of our research was to establish if there are any correlations between ultraprocessed food consumption and increased asthma prevalence or other respiratory outcomes. Meanwhille, it will be an important step to design some lifestyle recommendations with direct benefits for asthma treatment. NOVA system for food classification is a new concept addressing food quality. Ultraprocessed food, made entirely from substances derived from food and additives, that includes other sources of nutrients and energy, is not usually used in culinary preparation. How asthma outcomes are influenced by Western diet that contains a lot of processed food and what benefits could arise from the Mediterranean diet are subjects for interesting studies. Substantial correlations have been established between unhealthy diets, especially Western diet, ultraprocessed foods and food allergies and asthma pathogenesis and control. NOVA clasification of processing foods and dietary inflammatory index are helpful tools in early identifying of correct dietary approach in asthma. More research in nutrition recommendations for asthma patients must be done and practical guidelines in nutritional interventions are future steps.

Dietary Acid Load: A Novel Nutritional Target in Overweight/Obese Children with Asthma?

Obesity has been repeatedly linked to asthma, and several potential mechanisms have been proposed in the etiologies of the obese-asthma phenotype. Considering that lungs play an important role in systemic pH and acid–base regulation, are a key organ in asthma development, and that nutritional inadequacy of several nutrients and high dietary acid load can affect airway inflammation and reactivity, we aimed to test the hypothesis that dietary acid load may be associated with asthma in children. Data on 699 children (52% females), aged 7–12 years, were analyzed. Anthropometric measurements were performed to assess body mass index. Dietary acid load was calculated using potential renal acid load (PRAL) equations from a 24 h dietary recall administrated to children. Adjusted PRAL for total energy intake was applied with the use of the residual method. Lung function and airway reversibility were assessed with spirometry. Asthma was defined by a positive bronchodilation or self-reported medical diagnosis with reported symptoms (wheezing, dyspnea, or dry cough) in the past 12 months. After adjustment for energy intake, sex, age, parent’s education level, and physical activity, positive and significant associations were found between asthma and PRAL [odds ratio (OR) = 1.953, 95% CI = 1.024, 3.730) in overweight/obese children. Our findings suggest that dietary acid load might be a possible mechanism in overweight/obese-asthma phenotype development.