Sexual dimorphism in chronic respiratory diseases

Sex differences in the association between preexisting comorbidities and COVID-19-related symptoms during the COVID-19 pandemic in the Dominican Republic

Background

Sex-based differences in the impact of comorbidities on coronavirus disease 2019 (COVID-19) related symptoms remain underexplored due to the predominance of sex-aggregated data. We aimed to examine sex differences in the associations between preexisting comorbidities and COVID-19-related symptoms during the COVID-19 pandemic in the Dominican Republic.

Methods

We conducted a cross-sectional study using a questionnaire survey in the Dominican Republic between September 2021 and December 2021. Data on demographic factors, preexisting comorbidities, and self-reported COVID-19-related symptoms were collected. A multiple logistic regression model was used to separately identify associations between preexisting comorbidities and COVID-19-related symptoms in males and females.

Results

We included a total of 3,308 eligible individuals. Approximately 25% of the participants had preexisting comorbidities, and 31% of the participants experienced COVID-19-related symptoms. Multiple logistic regression analyses revealed that asthma (OR = 2.15, 95% CI = 1.20-3.85, p = 0.01) was associated with the presence of COVID-19-related symptoms in males. For females, chronic lung disease (OR = 5.39, 95% CI = 1.52-19.18, p = 0.009), hypertension (OR = 1.33, 95% CI = 1.00-1.77, p = 0.047) and diabetes mellitus (OR = 1.70, 95% CI = 1.07-2.71, p = 0.025) were correlated with COVID-19-related symptoms.

Conclusion

Our study findings observed sex-differences in the associations between preexisting comorbidities and COVID-19-related symptoms. Specifically, we observed that male individuals with asthma and females with chronic lung disease, hypertension, and diabetes mellitus had a greater likelihood of experiencing COVID-19-related symptoms. Future studies are needed to confirm the mechanism underlying these sex differences.

Female sex hormones and the oral contraceptive pill modulate asthma severity through GLUT-1

Females are disproportionately affected by asthma. An increased understanding of how female sex hormones influence key pathophysiological processes that underpin asthma may identify new, more effective asthma therapies, particularly for females with severe, poorly controlled asthma. We assessed the effects of oral ethinylestradiol/levonorgestrel (representing OCP use) and depot-medroxyprogesterone acetate (DMPA) and estradiol injections on key features of experimental asthma, and determined their effects on glucose transporter-1 (GLUT-1). The effects of OCP use on clinical asthma outcomes, and the relationships between estrogen receptors and type 2 (T2), non-T2, and GLUT-1 responses, in clinical asthma were also determined. OCP and DMPA reduce T2 responses, disease features, and lung expression of GLUT-1, whereas estradiol increases lung expression of GLUT-1, and results in severe, corticosteroid-insensitive, neutrophil-enriched disease, in experimental asthma. OCP use is associated with reduced T2 cytokine and GLUT-1 responses in clinical asthma. GLUT-1 expression is increased in sputum of severe asthmatics, and positively correlates with estrogen receptor expression and both T2 and non-T2 inflammatory responses. Significantly, OCP or GLUT-1 inhibition protects against obesity-associated or estradiol-induced, severe, experimental asthma, respectively. Together, these data show how female sex hormones and the OCP likely modulate asthma severity by modifying GLUT-1 responses in the airways.

The bioinformatics analysis and experimental validation of the carcinogenic role of EXO1 in lung adenocarcinoma

Background

Exonuclease 1 (EXO1), a protein involved in mismatch repair and recombination processes, has been identified as a prognostic biomarker in lung adenocarcinoma (LUAD). Nevertheless, its role in LUAD progression remains elusive. This study seeks to elucidate the functional significance of EXO1 in LUAD and evaluate its potential as a therapeutic target.

Materials and methods

Patient RNA-seq and clinical data were acquired from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Subsequently, a protein-protein interaction (PPI) network was constructed using differentially expressed genes (DEGs) to identify pivotal genes. Validation of the expression of signature genes was carried out through quantitative real-time PCR (qRT-PCR). Additionally, the association between EXO1 expression and clinical data was investigated. Immunohistochemistry was utilized to assess EXO1 expression in 93 cases of invasive pulmonary adenocarcinoma. Finally, cellular functional assays were conducted to investigate the impact of EXO1 on LUAD cells.

Results

Ten key molecules (PBK, ASPM, NCAPG, EXO1, MKI67, RRM2, AURKA, DLGAP5, UBE2C, and CDC6) exhibited significantly elevated expression levels in LUAD tissues. Moreover, elevated levels of EXO1 gene expression correlated strongly with advanced T, N, and M stages and were significantly associated with immune cell infiltration in LUAD. Furthermore, marked increases in EXO1 protein expression were observed in patients diagnosed with invasive pulmonary adenocarcinoma. Notably, patients diagnosed with invasive pulmonary adenocarcinoma who exhibited elevated EXO1 expression levels exhibited increased lymph node metastasis, pleural invasion, poor tumor differentiation, and advanced clinical stage. Additionally, this study employed wound healing assay and CCK-8 cell proliferation assays to investigate the significant role of EXO1 in promoting the growth and migration of lung adenocarcinoma cells.

Conclusions

This study identified ten hub genes associated with the initiation and progression of LUAD. Additionally, EXO1 may serve as a prognostic marker for LUAD patients, offering new perspectives for clinical treatments.

Paternal impact on the developmental programming of sexual dimorphism

Sexual dimorphism involves distinct anatomical, physiological, behavioral, and developmental differences between males and females of the same species, influenced by factors prior to conception and during early development. These sex-specific traits contribute to varied phenotypes and individual disease risks within and across generations and understanding them is essential in mammalian studies. Hormones, sex chromosomes, and imprinted genes drive this dimorphism, with over half of quantitative traits in wildtype mice showing sex-based variation. This review focuses on the impact of paternal non-genetic factors on sexual dimorphism. We synthesize current research on how paternal health before conception affects offspring phenotypes in a sex-specific manner, examining mechanisms such as DNA methylation, paternally imprinted genes, sperm RNA, and seminal plasma. Additionally, we explore how paternal influences indirectly shape offspring through maternal behavior, uterine environment, and placental changes, affecting males and females differently. We propose mechanisms modulating sexual dimorphism during development, underscoring the need for sex-specific documentation in animal studies.

The impact of airborne particulate matter-based pollution on the cellular and molecular mechanisms in chronic obstructive pulmonary disease (COPD)

Inhalation of particulate matter (PM), one of the many components of air pollution, is associated with the development and exacerbation of chronic respiratory diseases, such as chronic obstructive pulmonary disease (COPD). COPD is one of the leading causes of global mortality and morbidity, with a paucity of therapeutic options and a significant contributor to global health expenditure. This review aims to provide a mechanistic understanding of the cellular and molecular pathways that lead to the development of COPD following chronic PM exposure. Our review describes how the inhalation of PM can lead to lung parenchymal destruction and cellular senescence due to chronic pulmonary inflammation and oxidative stress. Following inhalation of PM, significant increases in a range of pro-inflammatory cytokines, mediated by the nuclear factor kappa B pathway are reported. This review also highlights how the inhalation of PM can lead to deleterious chronic oxidative stress persisting in the lung post-exposure. Furthermore, our work summarises how PM inhalation can lead to airway remodelling, with increases in pro-fibrotic cytokines and collagen deposition, typical of COPD. This paper also accentuates the interconnection and possible synergism between the pathophysiological mechanisms leading to COPD. Our work emphasises the serious health consequences of PM exposure on respiratory health. Elucidation of the cellular and molecular mechanisms can provide insight into possible therapeutic options. Finally, this review should serve as a stark reminder of the need for genuine action on air pollution to decrease the associated health burden on our growing global population.

Prenatal exposure to phthalates and childhood wheeze and asthma in the PROGRESS cohort

INTRODUCTION

Prenatal phthalate exposure may influence lung development and lead to wheezing and asthma in childhood, and these associations may vary by sex. Despite ubiquity of exposure, there is limited epidemiologic data on these associations in Latin America.

METHODS

We assessed 593 mother-child dyads enrolled in the Programming Research in Obesity, Growth, Environment, and Social Stressors birth cohort in Mexico City. We quantified 15 phthalate metabolites in 2nd and 3rd trimester maternal urine. Report of ever wheeze, wheeze in the past 12 months (current wheeze) and ever asthma were obtained using a validated survey when children were 4 and 6 years of age. We examined individual associations with modified Poisson models. Mixture effects were assessed using Bayesian Weighted Quantile Sum (BWQS) regression. All models were adjusted for child's sex, maternal age and education at enrollment, and parity.

RESULTS

In Poisson models, a doubling of mono (carboxy-isononyl) phthalate (MCNP) during the 2nd trimester was associated with higher risk of wheeze (RR: 1.14, 95 % CI: 1.01, 1.29), and asthma (RR: 1.44, 95 % CI: 1.05, 1.97) at 4 years of age. Higher concentrations of the sum of di-isononyl phthalate metabolites (∑DiNP) during the 2nd trimester were also associated with asthma at 4 years of age (RR: 1.30, 95 % CI: 1.04, 1.61). Mixture associations of phthalate metabolite concentrations during the 2nd trimester and asthma at 4 years of age were stronger in males (BWQS, OR: 1.94, 95 % CI: 0.90, 4.60; 90 % CrI: 1.04, 3.73) compared to females (BWQS, OR: 1.23, 95 % CI: 0.56, 2.88; 90 % CrI: 0.61, 2.55). Additionally, we observed stronger inverse associations between prenatal phthalate mixtures during the 3rd trimester and current wheeze at 4 and 6 years of age in females (BWQS, OR: 0.54, 90 % CrI: 0.35, 0.82; OR: 0.45, 90 % CrI: 0.22, 0.84) compared to males (BWQS, OR: 0.95, 90 % Cri: 0.68, 1.35; OR: 0.97, 90 % CrI: 0.59, 1.54).

CONCLUSIONS

Prenatal phthalate metabolite concentrations were associated with respiratory outcomes in childhood, with some evidence of sex specific effects. Future work investigating phthalate exposure and wheeze trajectories/lung function will be important for understanding how these may predict later disease.

Sarcoidosis and its relation to other immune-mediated diseases: Epidemiological insights

Several epidemiological studies show a co-occurrence of sarcoidosis with other immune-mediated diseases (IMD). There are many similarities between sarcoidosis and IMDs in their geographical distribution and risk factors. Understanding these similarities and identifying the differences can help us to better understand sarcoidosis and put it into context with other IMDs. In this review, we present the current knowledge about the overlap between sarcoidosis and other IMDs derived from epidemiological studies. Epidemiologic methods utilize study design and statistical analysis to describe the patterns in data and, ideally, identify causal relationships between an exposure and a health outcome. We discuss how study design and analysis may affect the interpretation of epidemiological studies on this topic and highlight some theories that attempt to explain the relation between sarcoidosis and other IMDs.

Copper oxide nanoparticles exacerbate chronic obstructive pulmonary disease by activating the TXNIP-NLRP3 signaling pathway

BACKGROUND

Although copper oxide nanoparticles (CuONPs) offer certain benefits to humans, they can be toxic to organs and exacerbate underlying diseases upon exposure. Chronic obstructive pulmonary disease (COPD), induced by smoking, can worsen with exposure to various harmful particles. However, the specific impact of CuONPs on COPD and the underlying mechanisms remain unknown. In this study, we investigated the toxic effects of CuONPs on the respiratory tract, the pathophysiology of CuONPs exposure-induced COPD, and the mechanism of CuONPs toxicity, focusing on thioredoxin-interacting protein (TXNIP) signaling using a cigarette smoke condensate (CSC)-induced COPD model.

RESULTS

In the toxicity study, CuONPs exposure induced an inflammatory response in the respiratory tract, including inflammatory cell infiltration, cytokine production, and mucus secretion, which were accompanied by increased TXNIP, NOD-like receptor protein 3 (NLRP3), caspase-1, and interleukin (IL)-1β. In the COPD model, CuONPs exposure induced the elevation of various indexes related to COPD, as well as increased TXNIP expression. Additionally, TNXIP-knockout (KO) mice showed a significantly decreased expression of NLRP3, caspase-1, and IL-1β and inflammatory responses in CuONPs-exposed COPD mice. These results were consistent with the results of an in vitro experiment using H292 cells. By contrast, TNXIP-overexpressed mice had a markedly increased expression of NLRP3, caspase-1, and IL-1β and inflammatory responses in CuONPs-exposed COPD mice.

CONCLUSIONS

We elucidated the exacerbating effect of CuONPs exposure on the respiratory tract with underlying COPD, as well as related signaling transduction via TXNIP regulation. CuONPs exposure significantly increased inflammatory responses in the respiratory tract, which was correlated with elevated TXNIP-NLRP3 signaling.

Biological Sex Is an Effect Modifier of Allergen-Mediated Alteration of the Lung Proteome

Asthma exhibits a distinct sex bias in the disease prevalence, severity, and response to therapy. However, sex-related differences in alterations of the lung proteome mediated by aeroallergens critical in asthma, such as house dust mites (HDM), remain unknown. In this study, we define sex-related differences in the lung proteome using an HDM-challenged mouse model by 1D LC-MS/MS. Sex-disaggregated data analysis showed that 406 proteins were uniquely altered in females, 273 proteins were uniquely altered in males, and 414 proteins were altered in both females and males in response to HDM. In a linear mixed model analysis, sex modified the HDM exposure effect for 163 proteins, i.e., a significant sex:exposure interaction was identified in 84 proteins in females and 35 proteins in males. Of these, 12 proteins showed a significant sex effect in both female and male lungs. We further selected 3 proteins Tjp1, Lamtor1, and G3BP2 for independent confirmation studies. Our findings detail the sex-specific lung proteome in response to an aeroallergen critical in asthma and demonstrate that sex is a significant effect modifier of HDM response. These results will serve as a valuable resource for delineating sex-specific mechanisms in aeroallergen-driven responses in asthma research.

Associations of prenatal exposure to phthalates and their mixture with lung function in Mexican children

Early life phthalates exposure has been associated with adverse respiratory outcomes. However, evidence linking prenatal phthalates exposure and childhood lung function has been inconclusive. Additionally, few studies have examined phthalates exposure as a mixture and explored sexually dimorphic associations. We aimed to investigate sex-specific associations of prenatal phthalates mixtures with childhood lung function using the PROGRESS cohort in Mexico (N = 476). Prenatal phthalate concentrations were measured in maternal urine collected during the 2nd and 3rd trimesters. Children's lung function was evaluated at ages 8-13 years. Individual associations were assessed using multivariable linear regression, and mixture associations were modeled using repeated holdout WQS regression and hierarchical BKMR; data was stratified by sex to explore sex-specific associations. We identified significant interactions between 2nd trimester phthalates mixture and sex on FEV1 and FVC z-scores. Higher 2nd trimester phthalate concentrations were associated with higher FEV1 (β = 0.054, 95 %CI: 0.005, 0.104) and FVC z-scores (β = 0.074, 95 % CI: 0.024, 0.124) in females and with lower measures in males (FEV1, β = -0.017, 95 %CI: -0.066, 0.026; FVC, β = -0.014, 95 %CI: -0.065, 0.030). This study indicates that prenatal exposure to phthalates is related to childhood lung function in a sex-specific manner.

Cardiorespiratory Fitness as a Predictor of Non-Cardiovascular Disease and Non-Cancer Mortality in Men

OBJECTIVE

To evaluate the association of 5 major cause-specific non-cardiovascular disease (CVD) and non-cancer deaths with cardiorespiratory fitness (CRF).

METHODS

Patients were 36,645 men (43.3±9.3 years) free of known CVD and cancer at baseline who completed a maximal treadmill graded exercise test during a preventive examination at the Cooper Clinic (Dallas, Texas) between 1971 and 2003. CRF was quantified as maximal treadmill exercise test duration and grouped as low (referent), moderate, and high. Cause-specific non-CVD non-cancer deaths were (1) diabetes or kidney disease, (2) chronic respiratory disease, (3) acute respiratory and infectious disease, (4) injuries, and (5) other non-CVD non-cancer deaths.

RESULTS

A total of 694 non-CVD non-cancer deaths occurred during an average of 17 years of follow-up. After adjustment for covariates, hazard ratios (95% confidence intervals) for moderate and high CRF, respectively, were 0.57 (0.47 to 0.69) and 0.43 (0.34 to 0.54) for overall non-CVD non-cancer deaths (P<.0001); 0.39 (0.28 to 0.54) and 0.17 (0.10 to 0.28) for diabetes or kidney disease (P<.001); 0.36 (0.22 to 0.59) and 0.09 (0.04 to 0.20) for chronic respiratory diseases (P<.001 for all); 0.74 (0.47 to 1.16) and 0.34 (0.19 to 0.61) for acute respiratory and infectious diseases (P<.01 for both); and 0.48 (0.35 to 0.66) and 0.38 (0.26 to 0.55) for any other non-CVD non-cancer deaths (P<.0001 for both).

CONCLUSION

Higher levels of CRF were significantly associated with lower risk of mortality from the 5 major non-CVD non-cancer causes. These results suggest that improvement in CRF may reduce non-CVD non-cancer deaths, which account for a significant proportion of adult mortality.

Use of oral moist tobacco (snus) in puberty and its association with asthma in the population-based RHINESSA study

OBJECTIVES

To investigate the association of early snus use initiation (≤15 years of age) with asthma and asthma symptoms.

DESIGN

Cross-sectional analysis of a population-based cohort.

SETTING

Study centres in Norway, Sweden, Iceland, Denmark and Estonia, from 2016 to 2019.

PARTICIPANTS

9002 male and female participants above 15 years of age of the Respiratory Health in Northern Europe, Spain and Australia study.

MAIN OUTCOME MEASURES

Current asthma and asthma symptoms.

RESULTS

The median age of study participants was 28 years (range 15-53) and 58% were women. 20% had used snus, 29% men and 14% women. Overall, 26% of males and 14% of females using snus started ≤15 years of age. Early snus use initiation was associated with having three or more asthma symptoms (OR 2.70; 95% CI 1.46 to 5.00) and a higher asthma symptom score (β-coefficient (β) 0.35; 95% CI 0.07 to 0.63) in women. These associations were weak in men (OR 1.23; 95% CI 0.78 to 1.94; β 0.16; 95% CI -0.06 to 0.38, respectively). There was evidence for an association of early snus initiation with current asthma (OR 1.72; 95% CI 0.88 to 3.37 in women; OR 1.31; 95% CI 0.84 to 2.06 in men). A sensitivity analysis among participants without smoking history showed stronger estimates for all three outcomes, in both men and women, statistically significant for three or more asthma symptoms in women (OR 3.28; 95% CI 1.18 to 9.10). Finally, no consistent associations with asthma outcomes were found for starting snus after age 15 years.

CONCLUSIONS

Snus initiation in puberty was associated with higher likelihood of asthma and asthma symptoms, with the highest estimates in females and those without smoking history. These results raise concerns about the health adversities of early snus initiation and emphasise the need for public health initiatives to protect young people from this tobacco product.

Sex differences in airway disease: estrogen and airway surface liquid dynamics

Biological sex differences exist for many airway diseases in which females have either worse or better health outcomes. Inflammatory airway diseases such as cystic fibrosis (CF) and asthma display a clear male advantage in post-puberty while a female benefit is observed in asthma during the pre-puberty years. The influence of menstrual cycle stage and pregnancy on the frequency and severity of pulmonary exacerbations in CF and asthma point to a role for sex steroid hormones, particularly estrogen, in underpinning biological sex differences in these diseases. There are many ways by which estrogen may aggravate asthma and CF involving disturbances in airway surface liquid (ASL) dynamics, inappropriate hyper-immune and allergenic responses, as well as exacerbation of pathogen virulence. The deleterious effect of estrogen on pulmonary function in CF and asthma contrasts with the female advantage observed in airway diseases characterised by pulmonary edema such as pneumonia, acute respiratory distress syndrome (ARDS) and COVID-19. Airway surface liquid hypersecretion and alveolar flooding are hallmarks of ARDS and COVID-19, and contribute to the morbidity and mortality of severe forms of these diseases. ASL dynamics encompasses the intrinsic features of the thin lining of fluid covering the airway epithelium which regulate mucociliary clearance (ciliary beat, ASL height, volume, pH, viscosity, mucins, and channel activating proteases) in addition to innate defence mechanisms (pathogen virulence, cytokines, defensins, specialised pro-resolution lipid mediators, and metabolism). Estrogen regulation of ASL dynamics contributing to biological sex differences in CF, asthma and COVID-19 is a major focus of this review.

Sex Hormones and Chronic Obstructive Pulmonary Disease: A Cross-Sectional Study and Mendelian Randomization Analysis

Background

Sex steroid hormones, including testosterone and estradiol, play significant roles in various aspects of pulmonary health and diseases. However, although there were a few studies trying to link sex hormones with COPD, their effect remained limited due to small sample size and insufficient causal results. This study aims to investigate the association between sex hormones and chronic obstructive pulmonary disease (COPD) based on the National Health and Nutrition Examination Survey (NHANES) database and evaluate causality via a two-sample Mendelian randomization (MR).

Methods

Data from NHANES 2013-2016 were enrolled for the cross-sectional study. The association between sex hormones and COPD was evaluated via multivariable logistic regression. Sex-stratified analysis, subgroup analyses and interaction tests were performed to further evaluate the correlation. For MR analysis, data were collected from genome-wide association studies and FinnGen datasets. The inverse-variance-weighted (IVW) approach, along with four other approaches, was applied in the analysis. Further sensitivity analysis was conducted to assess the existence of pleiotropy and heterogeneity.

Results

7,617 eligible participants were enrolled in the cross-sectional analysis. Negative associations were observed in both testosterone-COPD (OR 0.770, 95% CI 0.626, 0.948, p = 0.018) and estradiol-COPD (OR 0.794, 95% CI 0.688, 0.915, p = 0.005) relationships after covariate adjustments. However, the results from IVW-MR analysis showed that no causal relationship was observed in either the testosterone-COPD (OR 0.83, 95% CI 0.53, 1.29, p = 0.407) or estradiol-COPD (OR 0.74, 95% CI 0.23, 2.38, p = 0.616) relationship, which was also supported by the other four approaches (all p values > 0.05).

Conclusion

Although a significant negative association was observed between sex hormones and COPD, the results of MR analysis did not support the causality of this relationship. Our study suggested that sex hormones may indirectly rather than directly affect the development of COPD via potential covariates, which warranted further investigations.

node2vec2rank: Large Scale and Stable Graph Differential Analysis via Multi-Layer Node Embeddings and Ranking

Computational methods in biology can infer large molecular interaction networks from multiple data sources and at different resolutions, creating unprecedented opportunities to explore the mechanisms driving complex biological phenomena. Networks can be built to represent distinct conditions and compared to uncover graph-level differences-such as when comparing patterns of gene-gene interactions that change between biological states. Given the importance of the graph comparison problem, there is a clear and growing need for robust and scalable methods that can identify meaningful differences. We introduce node2vec2rank (n2v2r), a method for graph differential analysis that ranks nodes according to the disparities of their representations in joint latent embedding spaces. Improving upon previous bag-of-features approaches, we take advantage of recent advances in machine learning and statistics to compare graphs in higher-order structures and in a data-driven manner. Formulated as a multi-layer spectral embedding algorithm, n2v2r is computationally efficient, incorporates stability as a key feature, and can provably identify the correct ranking of differences between graphs in an overall procedure that adheres to veridical data science principles. By better adapting to the data, node2vec2rank clearly outperformed the commonly used node degree in finding complex differences in simulated data. In the real-world applications of breast cancer subtype characterization, analysis of cell cycle in single-cell data, and searching for sex differences in lung adenocarcinoma, node2vec2rank found meaningful biological differences enabling the hypothesis generation for therapeutic candidates. Software and analysis pipelines implementing n2v2r and used for the analyses presented here are publicly available.

Decreased Treg cells induced by bisphenol A is associated with up-regulation of PI3K/Akt/mTOR signaling pathway and Foxp3 DNA methylation in spleen of adolescent mice

The current study aimed to explore whether bisphenol A (BPA) exposure aggravated the decrease in Tregs induced by ovalbumin (OVA) in adolescent female mouse models of asthma, and whether the process was associated with mTOR-mediated signaling pathways and DNA methylation levels. A total of 40 female C57BL/6 mice at the age of four weeks were used and divided into five groups after 1 week of domestication. Each group consisted of eight mice: the control group, OVA group, OVA + BPA (0.1 μg mL-1) group, OVA + BPA (0.2 μg mL-1) group, and OVA + BPA (0.4 μg mL-1) group. Results revealed that Foxp3 protein levels decreased in the spleens of mice exposed to BPA compared to those in the OVA group. After an elevation in BPA dose, the mRNAs of methyltransferases (Dnmt1, Dnmt3a, and Dnmt3b) were gradually upregulated. The mechanism was related to the activity of TLR4/NF-κB and PI3K/Akt/mTOR signaling pathways and the enhancement of Foxp3 DNA methylation. Our results, collectively, provided a new view for studying the mechanisms underlying BPA exposure-induced immune dysfunction. Investigation of the regulatory mechanisms of DNA methylation in the abnormal Th immune response caused by BPA exposure could help reveal the causes and molecular mechanisms underlying the high incidence of allergic diseases in children in recent years.

Recipient donor sex combinations in solid organ transplantation and impact on clinical outcome: A scoping review

INTRODUCTION

Solid organ transplantation (SOT) is a lifesaving treatment for end-stage organ failure. Although many factors affect the success of organ transplantation, recipient and donor sex are important biological factors influencing transplant outcome. However, the impact of the four possible recipient and donor sex combinations (RDSC) on transplant outcome remains largely unclear.

METHODS

A scoping review was carried out focusing on studies examining the association between RDSC and outcomes (mortality, graft rejection, and infection) after heart, lung, liver, and kidney transplantation. All studies up to February 2023 were included.

RESULTS

Multiple studies published between 1998 and 2022 show that RDSC is an important factor affecting the outcome after organ transplantation. Male recipients of SOT have a higher risk of mortality and graft failure than female recipients. Differences regarding the causes of death are observed. Female recipients on the other hand are more susceptible to infections after SOT.

CONCLUSION

Differences in underlying illnesses as well as age, immunosuppressive therapy and underlying biological mechanisms among male and female SOT recipients affect the post-transplant outcome. However, the precise mechanisms influencing the interaction between RDSC and post-transplant outcome remain largely unclear. A better understanding of how to identify and modulate these factors may improve outcome, which is particularly important in light of the worldwide organ shortage. An analysis for differences of etiology and causes of graft loss or mortality, respectively, is warranted across the RDSC groups.

PRACTITIONER POINTS

Recipient and donor sex combinations affect outcome after solid organ transplantation. While female recipients are more susceptible to infections after solid organ transplantation, they have higher overall survival following SOT, with causes of death differing from male recipients. Sex-differences should be taken into account in the post-transplant management.

Helicobacter pylori Infection Does Not Protect Against Allergic Diseases: Evidence From a Pediatric Cohort From Northern Sardinia, Italy

BACKGROUND

The "hygiene hypothesis" states that reduced exposure to microbial antigens due to an excessively hygienic environment can increase the risk of developing autoimmune diseases, including atopic disorders and asthma. In recent decades, there has been a progressive decline in the prevalence of numerous microorganisms following improved hygienic-sanitary conditions. More specifically, several studies reported an inverse association between the reduction in Helicobacter pylori infection and the rise of asthma and allergic disorders.

AIM

To evaluate the prevalence of atopic disorders in a pediatric population in relation to seropositivity against H. pylori.

METHODS

Children from Northern Sardinia, Italy, referred to the local Children's Hospital for any reason, were investigated to identify risk factors, especially H. pylori infection, associated with atopic disorders. A validated questionnaire, including demographics, house size, history of breastfeeding, residence, school or daycare center attendance, exposure to animals, and a defined diagnosis of atopy-including asthma-was filled out by a trained pediatrician according to parents' answers and child records. A blood sample was collected from each participant and immunoglobulin G against H. pylori was assessed by a locally validated ELISA test.

RESULTS

The seroprevalence of H. pylori infection was 11.7% among 492 children (240 females). Thirty-two children had a confirmed diagnosis of asthma and 12 of allergy. No one child showed both conditions. Statistically significant differences in H. pylori seropositivity were not detected between children with or without atopy (8.4% vs. 12.6; p = 0.233). Although atopic disorders were more frequent in children exposed to traditional atopic risk factors, none of them showed to be significant after adjusting for all covariates.

CONCLUSIONS

Serologically assessed H. pylori infection was not significantly associated with a reduced risk of atopic diseases in children.

More than the SRY: The Non-Coding Landscape of the Y Chromosome and Its Importance in Human Disease

Historically, the Y chromosome has presented challenges to classical methodology and philosophy of understanding the differences between males and females. A genetic unsolved puzzle, the Y chromosome was the last chromosome to be fully sequenced. With the advent of the Human Genome Project came a realization that the human genome is more than just genes encoding proteins, and an entire universe of RNA was discovered. This dark matter of biology and the black box surrounding the Y chromosome have collided over the last few years, as increasing numbers of non-coding RNAs have been identified across the length of the Y chromosome, many of which have played significant roles in disease. In this review, we will uncover what is known about the connections between the Y chromosome and the non-coding RNA universe that originates from it, particularly as it relates to long non-coding RNAs, microRNAs and circular RNAs.

Risk factors contributing to infection with SARS-CoV-2 are modulated by sex

Throughout the early stages of the COVID-19 pandemic in Mexico (August-December 2020), we closely followed a cohort of n = 100 healthcare workers. These workers were initially seronegative for Immunoglobulin G (IgG) antibodies against SARS-CoV-2, the virus that causes COVID-19, and maintained close contact with patients afflicted by the disease. We explored the database of demographic, physiological and laboratory parameters of the cohort recorded at baseline to identify potential risk factors for infection with SARS-CoV-2 at a follow-up evaluation six months later. Given that susceptibility to infection may be a systemic rather than a local property, we hypothesized that a multivariate statistical analysis, such as MANOVA, may be an appropriate statistical approach. Our results indicate that susceptibility to infection with SARS-CoV-2 is modulated by sex. For men, different physiological states appear to exist that predispose to or protect against infection, whereas for women, we did not find evidence for divergent physiological states. Intriguingly, male participants who remained uninfected throughout the six-month observation period, had values for mean arterial pressure and waist-to-hip ratio that exceeded the normative reference range. We hypothesize that certain risk factors that worsen the outcome of COVID-19 disease, such as being overweight or having high blood pressure, may instead offer some protection against infection with SARS-CoV-2.

Respiratory Infection Triggering Severe Acute Exacerbations of Chronic Obstructive Pulmonary Disease

Background

Data are scarce on respiratory infections during severe acute exacerbation of chronic obstructive pulmonary disease (COPD). This study aimed to investigate respiratory infection patterns in the intensive care unit (ICU) and identify variables associated with infection type and patient outcome.

Methods

A retrospective, single-centre cohort study. All patients admitted (2015-2021) to our ICU for severe acute exacerbation of COPD were included. Logistic multivariable regression analysis was performed to predict factors associated with infection and assess the association between infection and outcome.

Results

We included 473 patients: 288 (60.9%) had respiratory infection and 139 (29.4%) required invasive mechanical ventilation. Eighty-nine (30.9%) had viral, 81 (28.1%) bacterial, 34 (11.8%) mixed, and 84 (29.2%) undocumented infections. Forty-seven (9.9%) patients died in the ICU and 67 (14.2%) in hospital. Factors associated with respiratory infection were temperature (odds ratio [+1°C]=1.43, P=0.008) and blood neutrophils (1.07, P=0.002). Male sex (2.21, P=0.02) and blood neutrophils were associated with bacterial infection (1.06, P=0.04). In a multivariable analysis, pneumonia (cause-specific hazard=1.75, P=0.005), respiratory rate (1.17, P=0.04), arterial partial pressure of carbon-dioxide (1.08, P=0.04), and lactate (1.14, P=0.02) were associated with the need for invasive MV. Age (1.03, P=0.03), immunodeficiency (1.96, P=0.02), and altered performance status (1.78, P=0.002) were associated with hospital mortality.

Conclusions

Respiratory infections, 39.9% of which were bacterial, were the main cause of severe acute exacerbation of COPD. Body temperature and blood neutrophils were single markers of infection. Pneumonia was associated with the need for invasive mechanical ventilation but not with hospital mortality, as opposed to age, immunodeficiency, and altered performance status.

Cigarette smoke-induced injury induces distinct sex-specific transcriptional signatures in mice tracheal epithelial cells

The airway epithelial barrier is crucial for defending against respiratory insults and diseases. Disruption of epithelial integrity contributes to respiratory diseases, and sex-specific differences in susceptibility and severity have been observed. However, sex-specific differences in the context of respiratory diseases are often overlooked, especially in murine models. In this study, we investigated the in vitro transcriptomics of male and female murine tracheal epithelial cells (mTECs) in response to chronic cigarette smoke (CS) exposure using an International Organization for Standardization (ISO) puff regimen. Our findings reveal sex-specific differences in the baseline characteristics of airway epithelial cells. Female mTECs demonstrated stronger barrier function and higher ciliary function compared with males. The barrier function was disrupted in both males and females following chronic CS, but the difference was more significant in females due to their higher baseline. Female mice exhibited transcriptional signatures suggesting dedifferentiation with increased basal cells and markers of cellular senescence. Pathway analysis indicated potential protective roles of planar cell polarity (PCP) in preventing dedifferentiation in male mice exposed to CS. We also observed sex-specific differences in the DNA damage response and antioxidant levels, suggesting distinct mechanisms underlying cellular stress. Understanding these sex-specific mechanisms could facilitate the development of targeted therapeutic strategies for lung diseases associated with environmental insults. Recognizing sex-based differences in disease susceptibility and treatment response can lead to personalized care and improved outcomes. Clinical trials should consider sex as a biological variable to develop effective interventions that address the unique differences between men and women in respiratory diseases.NEW & NOTEWORTHY The study underscores the importance of considering sex-specific differences in the airway epithelium in respiratory diseases such as COPD. Differences in gene expression between males and females at baseline and in response to chronic injury in the airway epithelium could have implications on disease susceptibility, both in COPD and other respiratory diseases. Therefore, understanding these differences is crucial for developing targeted therapies to treat respiratory diseases based on a sex-specific manner.

The polymorphisms of miR-146a SNPs are associated with asthma in Southern Chinese Han population

Asthma, a prevalent disease characterized by innate and adaptive immune responses, has been associated with several risk factors including miR-146a. To better understand the potential impact of miR-146a SNPs on asthma susceptibility and clinical features in Southern Chinese Han population, we conducted a case-control to analyze two functional SNPs (rs2910164 and rs57095329) of the miR-146a (394 patients with asthma and 395 healthy controls). Our findings suggest that the rs2910164 C/G genotype may increase the risk for asthma in females, while the rs57095329 G/G genotype may be involved in the regulation of clinical characteristics of males with asthma. In addition, we demonstrated that the SNPs rs2910164 C/G and rs57095329 A/G variations functionally affected the miR-146a levels in patients with asthma, and may alter structure of miR-146a. Our data are the first to suggest that miR-146a SNPs may be significantly associated with onset asthma in Southern Chinese Han population. Our studies may provide new insight into the potential significance of miR-146a SNPs in asthma.