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Background: Observational studies and meta‐analyses have indicated associations between blood lipid profiles and asthma. However, the causal association is unknown. Therefore, this study investigated the causal relationship between blood lipid profiles and asthma using bidirectional Mendelian randomization analysis. Methods and materials: Our analyses were performed using individual data from the Taiwan Biobank and summary statistics from the Asian Genetic Epidemiology Network (AGEN). The causal estimates between all genetic variants, exposures of interest and asthma were calculated using an inverse‐variance weighted method based on Taiwan Biobank data from 24,853 participants (mean age, 48.8 years; 49.8% women). Sensitivity analyses, including the weighted median, MR Egger regression, MR‐PRESSO, mode‐based estimate, contamination mixture methods, and leave‐one‐out analysis, were applied to validate the results and detect pleiotropy. Results: In the inverse‐variance weighted (IVW) analyses, we found evidence of a significant causal effect of an increased level of low‐density lipoprotein cholesterol on asthma risk (βIVW = 1.338, p = 0.001). A genetically decreased level of high‐density lipoprotein cholesterol was also associated with asthma risk (βIVW = −0.338, p = 0.01). We also found that an increased level of total cholesterol was associated with an increased risk of asthma (βIVW = 1.343, p = 0.001). Several sensitivity analyses generated consistent findings. We did not find evidence to support the causality between asthma and blood lipid profiles in either direction. Conclusion: Our results supported the causal relationship between higher levels of LDL cholesterol and total cholesterol and lower levels of HDL cholesterol with an increased risk of asthma. [ABSTRACT FROM AUTHOR]

Exposure to BTEX has been suggested to be a potential risk factor for asthma,[[1], [3]] a heterogeneous disease with unclear etiology, but its individual risk for adult asthma and its phenotypic clusters remains unclear. An hourly grid-scale model was utilized to estimate the residence-based ambient air BTEX levels and the time-lag effect (lag-0, lag-1, lag-2, lag-3, lag-4, and lag-5) on the daily asthma ERVs and outpatient visits. Abbreviations 2,4-DPMA N -acetyl- S -(2,4-dimethylbenzene)- l -cysteine 4-HNE 4-hydroxynonenal BMA N -acetyl- S -(benzyl)- l -cysteine BTEX benzene, toluene, ethylbenzene, and xylene C1P ceramide-1-phosphate ERV emergency room visit HEL N -(hexanoyl)-lysine LC-MS liquid chromatography-tandem mass spectrometry NHIRD National Health Insurance Research Database PGA phenylglyoxylic acid PMA N -acetyl- S -phenyl- l -cysteine RR relative risk S1P sphingosine-1-phosphate SL sphingolipid VOCs volatile organic compounds In a combined population-based and case-control study, exposure to benzene, toluene, ethylbenzene, and xylene (BTEX), particularly benzene, concomitant with increased oxidative stress and sphingolipid dysregulation, posed a significant, but differential, risk for current asthma, its severity, and phenotypic clusters. [Extracted from the article]

Abstract Background To investigate whether the toll-like receptor 2 polymorphisms could influence susceptibility to pulmonary TB, its phenotypes, and blood lymphocyte subsets. Methods A total of 368 subjects, including 184 patients with pulmonary TB and 184 healthy controls, were examined for TLR2 polymorphisms over locus -100 (microsatellite guanine-thymine repeats), -16934 (T>A), -15607 (A>G), -196 to -174 (insertion>deletion), and 1350 (T>C). Eighty-six TB patients were examined to determine the peripheral blood lymphocyte subpopulations. Results We newly identified an association between the haplotype [A-G-(insertion)-T] and susceptibility to pulmonary TB (p = 0.006, false discovery rate q = 0.072). TB patients with systemic symptoms had a lower -196 to -174 deletion/deletion genotype frequency than those without systemic symptoms (5.7% vs. 17.7%; p = 0.01). TB patients with the deletion/deletion genotype had higher blood NK cell counts than those carrying the insertion allele (526 vs. 243.5 cells/μl, p = 0.009). TB patients with pleuritis had a higher 1350 CC genotype frequency than those without pleuritis (12.5% vs. 2.1%; p = 0.004). TB patients with the 1350 CC genotype had higher blood NK cell counts than those carrying the T allele (641 vs. 250 cells/μl, p = 0.004). TB patients carrying homozygous short alleles for GT repeats had higher blood NK cell counts than those carrying one or no short allele (641 vs. 250 cells/μl, p = 0.004). Conclusions TLR2 genetic polymorphisms influence susceptibility to pulmonary TB. TLR2 variants play a role in the development of TB phenotypes, probably by controlling the expansion of NK cells.

We hypothesized that epigenetics is a link between smoking/allergen exposures and the development of Asthma and chronic obstructive pulmonary disease (ACO). A total of 75 of 228 COPD patients were identified as ACO, which was independently associated with increased exacerbations. Microarray analysis identified 404 differentially methylated loci (DML) in ACO patients, and 6575 DML in those with rapid lung function decline in a discovery cohort. In the validation cohort, ACO patients had hypermethylated PDE9A (+ 30,088)/ZNF323 (− 296), and hypomethylated SEPT8 (− 47) genes as compared with either pure COPD patients or healthy non-smokers. Hypermethylated TIGIT (− 173) gene and hypomethylated CYSLTR1 (+ 348)/CCDC88C (+ 125,722)/ADORA2B (+ 1339) were associated with severe airflow limitation, while hypomethylated IFRD1 (− 515) gene with frequent exacerbation in all the COPD patients. Hypermethylated ZNF323 (− 296) / MPV17L (+ 194) and hypomethylated PTPRN2 (+ 10,000) genes were associated with rapid lung function decline. In vitro cigarette smoke extract and ovalbumin concurrent exposure resulted in specific DNA methylation changes of the MPV17L / ZNF323 genes, while 5-aza-2′-deoxycytidine treatment reversed promoter hypermethylation-mediated MPV17L under-expression accompanied with reduced apoptosis and decreased generation of reactive oxygen species. Aberrant DNA methylations may constitute a determinant for ACO, and provide a biomarker of airflow limitation, exacerbation, and lung function decline. [ABSTRACT FROM AUTHOR]

Objectives: Previous studies reported that environmental factors, particularly the work environment, were related to quality of life (QoL) in patients with asthma. However, the pathway that links workplace and QoL in adults with asthma is still not clear. The aim of this study was to explore the comprehensive environmental factors, asthma control, and QoL pathways in patients with asthma. Study Design and Setting: Two cohorts of patients with asthma were established, including a prospective phase cohort in 2006 and a cross-sectional phase cohort in 2012. The Asthma Control Test was used to determine the level of disease control, and QoL was assessed by using the Taiwanese version of an asthma quality-of-life questionnaire. In 2014, a structural equation model was applied to explore the pathways from the risk factors to QoL. Results: The structural equation model for predicting QoL provided a good fit (χ2 [degrees of freedom] = 43.81 [38]; root mean square error of approximation 0.021 [90% confidence interval, 0.001-0.044]) after combining the two cohorts. The wheeze frequency, allergic response frequency, parental asthma, and asthma control were directly associated with QoL. We found that patients who were obese and who worked in poor environments had increased work symptoms and wheeze frequency during the previous year in a cross-sectional phase cohort. However, we did not find that body mass index was a significant factor in a prospective cohort. The patients with obesity and with frequent work symptoms, which induced poor asthma control, were possible mechanisms in the pathway from workplace exposure to poor QoL in the observed adults with asthma in our combined data. Conclusion: Body mass index, the work environment, and the wheeze frequency should be considered when assessing asthma control and QoL in adult patients with asthma. Patients who reduce their body weight or avoid exposure to poor workplaces may find this useful for their asthma control and improvement of their QoL. [ABSTRACT FROM AUTHOR]

Background: Elafin inhibits serine proteases, such as human neutrophil elastase and proteinase 3, to prevent excessive damage during inflammation. However, the relationship between elafin and asthma is still unclear. Microarray technology was used to evaluate smoking- and asthma-related biomarkers in a discovery-driven manner. We identified candidate genes, e.g., proteinase inhibitor 3 (PI3), related to asthma and smoking from gene expression microarray data sets and evaluated their potential as biomarkers for asthma. Methods: We used human genome microarray data sets from smoking- and asthma-related gene expression data sets and performed real-time quantitative polymerase chain reaction to measure and validate differences in gene expression. We also recruited adult patients with asthma and age- and sex-matched control patients who were administered a structured questionnaire and evaluated for lung function and plasma elafin levels, which are encoded by the PI3 gene. Results: Six significantly altered candidate genes, PI3, protein kinase C iota, phosphoserine phosphatase, IQ motif-containing GTPase activating protein 1, interleukin 13 receptor α 1, and signal transducing adaptor molecule SH3 domain and ITAM motif 2, were identified from comparisons across the four asthma- and four smoking-related data sets included in this study. An in vitro study of human airway epithelial cells (A549) and a human monocytic cell line (THP-1) demonstrated that PI3 messenger RNA levels were significantly altered by nicotine exposure. Elafin concentration was significantly higher in control patients than in patients with asthma (p < 0.001). The plasma elafin concentration in the highest quartile (≥12.69 ng/mL) was inversely associated with asthma (adjusted odds ratio 0.122 [95% confidence interval, 0.053-0.278]) compared with the lowest quartile (<5.82 ng/mL) after adjusting for age, sex, smoking status, waist-to-hip ratio, percentage predicted forced expiratory volume in 1 second, cockroaches in the home, incense burning, and family history. Conclusion: Our study revealed that high elafin levels identified in smoking- and asthma-related microarray data sets and an epidemiologic study significantly reduced the risk of asthma. Further studies of elafin as a potential therapy for asthma are warranted. [ABSTRACT FROM AUTHOR]

Background: Betel nut is commonly used in many countries. Despite evidence suggesting an association with asthma, few studies have investigated the connection between betel nut use and asthma; thus, the underlying mechanism for the association with asthma is also unclear. The aim of this study was to investigate the association between betel chewing and asthma as well as the associations of plasma arecoline (a biomarker for exposure) and eotaxin-1 (a potential mediator) with asthma and lung function. Methods: We recruited 600 hospital-based asthmatic patients and 1200 age- and gender-matched community controls in southern Taiwan. To clarify the mechanism of action for eotaxin-1 in the association between betel chewing and asthma, we also designed an in vitro experiment to study the functional associations between arecoline exposure and eotaxin-1 levels. Results: A significant association was found between asthma and current betel chewing (adjusted odds ratio 2.05, 95% CI = 1.12–3.76), which was independent of potential confounders but was attenuated following adjustment for eotaxin-1. Arecoline and eotaxin-1 levels were positively correlated (Spearman r = 0.303, p = 0.02), while arecoline and arecaidine were negatively correlated with lung function. Functionally, arecoline alone does not induce eotaxin-1 release in vitro from dermal and gingival fibroblasts. However, in the presence of IL-4 and TNF-alpha, arecoline at 100 μg/ml induced more eotaxin-1 release than arecoline at 0 μg/ml (2700±98 pg/ml vs 1850±142 pg/ml, p = 0.01 in dermal fibroblast cells, and 1489±78 pg/ml vs 1044±95 pg/ml, p = 0.03 in gingival fibroblast cells, respectively). Conclusion: Betel chewing is associated with asthma in this population, with arecoline induction of eotaxin-1 supported as a plausible causal pathway. [ABSTRACT FROM AUTHOR]

Background: Adult asthma is caused by interaction effects of multiple genetic and environmental factors. Some studies have suggested that antioxidant enzyme activity and gene polymorphisms may play important roles in the context of asthma. Therefore, our study objectives were to investigate the association between asthma, antioxidant activities and the polymorphisms of manganese superoxide dismutase (Mn-SOD) or catalase (CAT). Materials and Methods: A case-control study, for which we recruited 250 asthmatic adults and 250 age- and sex-matched controls. All subjects completed a questionnaire. Waist and hip circumference measurements, a lung function test and DNA genotyping were performed. In total, 50 incident cases and 50 matched controls who were non-smokers or had quit smoking for at least 1 year were selected in order to investigate SOD and CAT activity levels. Results: In our study, we did not find a significant association between Mn-SOD Ala16Val, CAT C-262T and asthma. The level of SOD activity in new-onset asthma patients was significantly lower than in control subjects (p < 0.0005). The level of CAT activity in new-onset asthma patients was significantly higher than in control subjects (p < 0.0005). Conclusions: The levels of SOD and CAT activity were significantly related to adult asthma. SOD and CAT activity may be good tools to differentiate potential asthma sufferers. This would enable us to further investigate the mechanism of defective antioxidant enzymes in the context of asthma pathogenesis. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The article "Exploring Occupational Asthmagen-Related Asthma Phenotypes: A Cluster Analysis and Machine Learning Study" investigates different phenotypes of work-related asthma (WRA) using cluster analysis and machine learning. The study identifies distinct phenotypes of WRA based on occupational exposure and asthma characteristics, linking phenotype understanding to practical applications. The research aims to enhance patient care for asthmatics by predicting severe asthma and understanding the impact of occupational exposure on asthma outcomes. [Extracted from the article]

The aim of this study is to explore the role of microRNAs (miR)-21/23a/146a/150/155 targeting the toll-like receptor pathway in active tuberculosis (TB) disease and latent TB infection (LTBI). Gene expression levels of the five miRs and predicted target genes were assessed in peripheral blood mononuclear cells from 46 patients with active pulmonary TB, 15 subjects with LTBI, and 17 non-infected healthy subjects (NIHS). THP-1 cell lines were transfected with miR-23a-3p mimics under stimuli with Mycobacterium TB-specific antigens. Both miR-155-5p and miR-150-5p gene expressions were decreased in the active TB group versus the NIHS group. Both miR-23a-3p and miR-146a-5p gene expressions were decreased in active TB patients with high bacterial burden versus those with low bacterial burden or control group (LTBI + NIHS). TLR2, TLR4, and interleukin (IL)10 gene expressions were all increased in active TB versus NIHS group. MiR-23a-3p mimic transfection reversed ESAT6-induced reduction of reactive oxygen species generation, and augmented ESAT6-induced late apoptosis and phagocytosis, in association with down-regulations of the predicted target genes, including tumor necrosis factor (TNF)-α, TLR4, TLR2, IL6, IL10, Notch1, IL6R, BCL2, TGF-β1, SP1, and IRF1. In conclusion, the down-regulation of miR-23a-3p in active TB patients with high bacterial burden inhibited mononuclear cell function and phagocytosis through TLR4/TNF-α/TGF-β1/IL-10 signaling via targeting IRF1/SP1. [ABSTRACT FROM AUTHOR]

We hypothesized that DNA methylation patterns may contribute to the development of active pulmonary tuberculosis (TB). Illumina's DNA methylation 450 K assay was used to identify differentially methylated loci (DML) in a discovery cohort of 12 active pulmonary TB patients and 6 healthy subjects (HS). DNA methylation levels were validated in an independent cohort of 64 TB patients and 24 HS. Microarray analysis identified 1028 DMLs in TB patients versus HS, and 3747 DMLs in TB patients after versus before anti-TB treatment, while autophagy was the most enriched signaling pathway. In the validation cohort, PARP9 and miR505 genes were hypomethylated in the TB patients versus HS, while RASGRP4 and GNG12 genes were hypermethylated, with the former two further hypomethylated in those with delayed sputum conversion, systemic symptoms, or far advanced lesions. MRPS18B and RPTOR genes were hypomethylated in TB patients with pleural involvement. RASGRP4 gene hypermethylation and RPTOR gene down-regulation were associated with high mycobacterial burden. TB patients with WIPI2/GNG12 hypermethylation or MRPS18B/FOXO3 hypomethylation had lower one-year survival. In vitro ESAT6 and CFP10 stimuli of THP-1 cells resulted in DNA de-methylation changes of the PARP9, RASGRP4, WIPI2, and FOXO3 genes. In conclusions, aberrant DNA methylation over the PARP9/miR505/RASGRP4/GNG12 genes may contribute to the development of active pulmonary TB disease and its clinical phenotypes, while aberrant DNA methylation over the WIPI2/GNG12/MARPS18B/FOXO3 genes may constitute a determinant of long-term outcomes. [ABSTRACT FROM AUTHOR]

Objective: To identify patients at high risk of relapse after anti-tuberculosis (TB) therapy or with poor long-term outcomes. Methods: Fifty-one patients with pulmonary TB: 7 were classified as high association with both cavitations on initial chest radiography and positive sputum smear/cultures after two months of anti-TB treatment (HA group); 19 medium association (MA, one risk alone); and 25 low association (LA, neither risk). Serum interferon (IFN)-γ-inducible protein 10 (IP-10), interleukin-17 (IL-17), and C-reactive protein levels were investigated. Results: There was a trend towards higher serum IP-10 levels (p=0.042) for HA patients throughout the 6-month treatment period. Month-2 IP-10 levels were higher in the HA than in the MA/LA group (656.2 ± 234.4 vs. 307.6 ± 258.5 pg/ml, adjusted p =0.005). Receiver operating characteristic curves showed that the risk of relapse was well-captured by month-2 IP-10 levels at a cut-off value of 431 pg/ml (AUC=0.857, 95% CI 0.75-0.97, p =0.003). Month-2 serum IL-17 levels were lower in non-survivors than survivors (15.7 ± 2.9 pg/ml vs. 24.6 ± 8.2 pg/ml, p=0.001). Multivariate analysis demonstrated that a month-2 serum IL-17 level of &les; 17 pg/ml (p =0.026) was independently associated with all-cause mortality. Conclusions: Serum IP-10 and IL-17 levels after 2 months of anti-TB treatment may be biomarkers for estimating risk of both cavitation and delayed sputum conversion, and for predicting long-term mortality, respectively. [ABSTRACT FROM AUTHOR]