Metabolomic pathways in food allergy.

Food allergy (FA) is a widespread issue, affecting as many as 10% of the population. Over the past two to three decades, the prevalence of FA has been on the rise, particularly in industrialized and westernized countries. FA is a complex, multifactorial disease mediated by type 2 immune responses and involving environmental and genetic factors. However, the precise mechanisms remain inadequately understood. Metabolomics has the potential to identify disease endotypes, which could beneficially promote personalized prevention and treatment. A metabolome approach would facilitate the identification of surrogate metabolite markers reflecting the disease activity and prognosis. Here, we present a literature overview of recent metabolomic studies conducted on children with FA.

Administration of chromium picolinate and meloxicam alleviates regrouping stress in dairy heifers.

Objective: This research was performed to investigate effect of administering chromium (Cr) and meloxicam (MEL) on growth performance, cortisol and blood metabolite, and behaviors in young regrouped heifers. Methods: Fifty Holstein dairy heifers (body weight (BW) 198 ± 32.7 kg and 6.5 ± 0.82 months of age) were randomly assigned to non-regrouped group or four regrouped groups. Non-regrouped animals were held in the same pen throughout entire experimental period (NL: non-regrouping and administration of lactose monohydrate (LM; placebo). For regrouping groups, two or three heifers maintained in four different pens for 2 weeks were regrouped into a new pen and assigned to one of four groups: regrouping and LM administration (RL); regrouping and Cr administration (RC); regrouping and MEL administration (RM), and regrouping and Cr and MEL administration (RCM). LM (1 mg/kg BW), Cr (0.5 mg Cr picolinate/kg dry matter intake), and MEL (1 mg/kg BW) were orally administered immediately before regrouping. Blood was collected before regrouping (0 h) and at 3, 9, and 24 h and 7 and 14 d thereafter. Behaviors were recorded for 7 consecutive days after regrouping. Results: Average daily gain was lower (P < 0.05) in RL than NL heifers, but was higher (P < 0.05) in RM, RC, and RCM than RL heifers. RL heifers had higher (P < 0.05) cortisol than NL heifers on d 1 after regrouping. The cortisol concentrations in RC, RM, and RCM groups were lower (P < 0.05) than in RL treatment 1 d after regrouping. Displacement behavior was greater (P < 0.05) in RL group than all other groups at 2, 3, and 6 d after regrouping. Conclusion: Regrouping caused temporal stress, reduced growth performance, and increased displacement behavior in heifers. Administering Cr and MEL recovered the retarded growth rate and reduced displacement behavior, thereby alleviating regrouping stress.

Allergic rhinitis phenotypes with distinct transcriptome profiles in children: A birth cohort.

BACKGROUND: Allergic rhinitis (AR) phenotypes in childhood are unclear. OBJECTIVES: This study sought to determine AR phenotypes and investigate their natural course and clinical and transcriptomic characteristics. METHODS: Latent class trajectory analysis was used for phenotyping AR in 1050 children from birth through 12 years using a birth cohort study. Blood transcriptome analyses were performed to define the underlying mechanisms of each phenotype. RESULTS: Five AR phenotypes were identified: early onset (n = 88, 8.4%), intermediate transient (n = 110, 10.5%), late onset (n = 209, 19.9%), very late onset (n=187, 17.8%), and never/infrequent (n = 456, 43.4%). Children with early-onset AR were associated with higher AR severity and sensitizations to foods at age 1 year and inhalants at age 3 years and asthma symptoms, but not with bronchial hyperresponsiveness (BHR). Children with late-onset AR phenotype associated with sensitizations to various foods at age 1 year but not from age 3 years, and to inhalants from age 7 years and with asthma with BHR. Children with very late-onset AR phenotype associated with sensitizations to foods throughout preschool age and to inhalants at ages 7 and 9 years and with asthma with BHR. Transcriptome analysis showed that early-onset AR was associated with viral/bacterial infection-related defense response, whereas late-onset AR was associated with T cell-related immune response. CONCLUSIONS: Early-onset AR phenotype was associated with sensitization to foods and inhalants at an early age and asthma symptoms, but not with BHR, whereas very late- and late-onset AR phenotypes were positively associated with sensitization to inhalants and asthma with BHR. Transcriptomic analyses indicated that early- and late-onset AR phenotypes had distinct underlying mechanisms related to AR as well.

Insights from the COCOA birth cohort: The origins of childhood allergic diseases and future perspectives.

The ongoing COhort for Childhood Origin of Asthma and allergic diseases (COCOA) study is a prospective birth cohort investigating the origin and natural courses of childhood allergic diseases, including atopic dermatitis, food allergy, allergic rhinitis and asthma, with long-term prognosis. Initiated under the premise that allergic diseases result from a complex interplay of immune development alterations, environmental exposures, and host susceptibility, the COCOA study explores these dynamic interactions during prenatal and postnatal periods, framed within the hygiene and microbial hypotheses alongside the developmental origins of health and disease (DOHaD) hypothesis. The scope of the COCOA study extends to genetic predispositions, indoor and outdoor environmental variables affecting mothers and their offsprings such as outdoor and indoor air pollution, psychological factors, diets, and the microbiomes of skin, gut, and airway. We have embarked on in-depth investigations of diverse risk factors and the pathophysiological underpinnings of allergic diseases. By employing multi-omics approaches-proteomics, transcriptomics, and metabolomics-we gain deeper insights into the distinct pathophysiological processes across various endotypes of childhood allergic diseases, incorporating the exposome using extensive resources within the COCOA study. Integration with large-scale datasets, such as national health insurance records, enhances robustness and mitigates potential limitations inherent to birth cohort studies. As part of global networks focused on childhood allergic diseases, the COCOA study fosters collaborative research across multiple cohorts. The findings from the COCOA study are instrumental in informing precision medicine strategies for childhood allergic diseases, underpinning the establishment of disease trajectories.

Clinical Manifestations and Genotype of Primary Ciliary Dyskinesia Diagnosed in Korea: Multicenter Study.

PURPOSE: Primary ciliary dyskinesia (PCD) is a genetically heterogeneous disorder that leads to secondary ciliary dysfunction. PCD is a rare disease, and data on it are limited in Korea. This study systematically evaluated the clinical symptoms, diagnostic characteristics, and treatment modalities of pediatric PCD in Korea. METHODS: This Korean nationwide, multicenter study, conducted between January 2000 and August 2022, reviewed the medical records of pediatric patients diagnosed with PCD. Prospective studies have been added to determine whether additional genetic testing is warranted in some patients. RESULTS: Overall, 41 patients were diagnosed with PCD in 15 medical institutions. The mean age at diagnosis was 11.8 ± 5.4 years (range: 0.5 months-18.9 years). Most patients (40/41) were born full term, 15 (36.6%) had neonatal respiratory symptoms, and 12 (29.3%) had a history of admission to the neonatal intensive care unit. The most common complaint (58.5%) was chronic nasal symptoms. Thirty-three patients were diagnosed with transmission electron microscopy (TEM) and 12 patients by genetic studies. TEM mostly identified outer dynein arm defects (alone or combined with inner dynein arm defects, n = 17). The genes with the highest mutation rates were DNAH5 (3 cases) and DNAAF1 (3 cases). Rare genotypes (RPGR, HYDIN, NME5) were found as well. Chest computed tomography revealed bronchiectasis in 33 out of 41 patients. Among them, 15 patients had a PrImary CiliAry DyskinesiA Rule score of over 5 points. CONCLUSIONS: To our knowledge, this is the first multicenter study to report the clinical characteristics, diagnostic methods, and genotypes of PCD in Korea. These results can be used as basic data for further PCD research.

Complete genome assembly of Enterococcus faecalis strain HL1, isolated from an infant fecal sample.

We present the complete genome sequence of Enterococcus faecalis strain HL1, isolated from infant feces. E. faecalis gains significant attention for its therapeutic potential. The genome of E. faecalis HL1 consists of a 2.7 Mb circular chromosome with no plasmids, and it contains a total of 2,546 predicted coding genes.

Broncho-Vaxom bacterial lysate prevents asthma via acetate enhancement in mouse model.

PURPOSE: Broncho-Vaxom (BV) is known to attenuate allergic airway inflammation and chronic bronchitis in humans, but the underlying mechanism of this gut-mediated immunity remains unclear. This study investigated the effects of an oral BV on gut and systemic short-chain fatty acids (SCFAs) and immune responses. METHODS: Oral BV was administered daily for 15 days prior to commencing the study in an asthma mouse model. Asthma was induced by ovalbumin (OVA) sensitization followed by a challenge with 1% OVA by inhalation. Asthmatic phenotypes, gut- and systemic- immune responses, and SCFAs in the cecum and blood were then investigated. RESULTS: Airway hyperresponsiveness, total immunoglobulin E production, and pulmonary inflammation were all significantly suppressed by BV. The interleukin-13 level was also suppressed, whereas TGF-ß expression was increased, in the lungs of the BV-treated mice. The regulatory T (Treg) cell numbers were increased in the small intestine, and the acetate level was increased in the cecum and serum after BV treatment. The levels of acetate in the cecum and serum were negatively correlated with airway hyperresponsiveness and with the eosinophil numbers in the BAL fluid of the OVA-induced mice. There was a positive correlation between the acetate levels in the feces and serum and the lung expression of TGF-ß in the asthma mice. CONCLUSIONS: Oral BV administration appears to prevent allergic inflammation by enhancing Treg cell proliferation and acetate production in an asthmatic mouse model.

The alternative bile acid pathway can predict food allergy persistence in early childhood.

BACKGROUND: Mechanisms underlying persistent food allergy (FA) are not well elucidated. The intestinal mucosa is the primary exposure route of food allergens. However, no study has examined intestinal metabolites associated with FA persistence. The goal of this study was to investigate intestinal metabolites and associated microbiomes in early life that aid in determining the development and persistence of FA. METHODS: We identified metabolomic alterations in the stool of infants according to FA by mass spectrometry-based untargeted metabolome profiling. The targeted metabolomic analysis of bile acid metabolites and stool microbiome was performed. Bile acid metabolite composition in infancy was evaluated by characterizing the subjects at the age of 3 into FA remission and persistent FA. RESULTS: In untargeted metabolomics, primary bile acid biosynthesis was significantly different between subjects with FA and healthy controls. In targeted metabolomics for bile acids, intestinal bile acid metabolites synthesized by the alternative pathway were reduced in infants with FA than those in healthy controls. Subjects with persistent FA were also distinguished from healthy controls and those with FA remission by bile acid metabolites of the alternative pathway. These metabolites were negatively correlated with specific IgE levels in egg white. The abundance of intestinal Clostridia was decreased in the FA group and was correlated with ursodeoxycholic acid. CONCLUSION: Intestinal bile acid metabolites of the alternative pathway could be predictive biomarkers for persistent FA in early childhood. These findings require replication in future studies.

Therapeutic effectiveness of probiotics for atopic dermatitis: A systematic review and meta-analysis of randomized controlled trials with subgroup analysis.

BACKGROUND: The effect of probiotics in the treatment of atopic dermatitis (AD) is inconclusive, partially due to the heterogeneities of AD. OBJECTIVE: The aim of the present study was to investigate the efficacy of probiotics in the treatment of AD with a subgroup analysis according to country, severity of AD, duration of supplementation, and probiotic strain. METHODS: Original articles reporting the therapeutic efficacy of probiotics for AD were identified by searching PubMed, Cochrane Library databases, and Embase from inception to September 30, 2022. RESULTS: This meta-analysis included 1,382 patients with AD from 25 randomized controlled trials. Probiotic supplementation was effective for the treatment of AD, reflected in a significant decrease in the SCORing Atopic Dermatitis (SCORAD) index (SMD, -4.0; 95%CI, -7.3 to -0.7). The subgroup analysis showed a significant therapeutic effect for AD among patients with mild or moderate AD (SMD, -1.4; 95%CIs -2.2 to -0.7), in those supplemented for more than three months (SMD, -5.1; 95%CIs -9.7 to -0.4), and in those supplemented with a probiotic that contained Lactobacillus spp. strains combined with or without other strains (SMD, -4.4; 95%CIs -8.0 to -0.8). In addition, the therapeutic effects of probiotics showed differences according to country and geographic region. CONCLUSIONS: Probiotics can be beneficial for the treatment of AD, and their therapeutic effect may be individually tailored to improve it based on the severity of AD, strain of probiotics, duration of supplementation, and geographic region.

Blood eosinophil related to maternal allergic rhinitis is associated with the incidence of allergic rhinitis in offspring: COCOA study.

OBJECTIVE: The identification of allergic rhinitis (AR) in early life is important for the target of intervention. AR is caused by various environmental factors, including house dust mites. We investigated the relationship between the Dermatophagoides farinae (Der f)-IgE and eosinophil in mothers with AR at delivery and the eosinophil levels and AR incidence in children. METHODS: The study participants were 983 mother-child pairs from the COhort for Childhood Origin of Asthma and Allergic Diseases. AR was diagnosed by a doctor at delivery in mother and at 3 years of age in offspring. The association between eosinophil level and AR was assessed using logistic regression analysis. RESULTS: The Der f-IgE level in mother having AR at delivery was associated with the mother's eosinophil level, and the mother's eosinophil level was associated with the child's eosinophil level both at age 1 and 3. The risk of AR at age 3 in children was increased according to increased eosinophil levels in mothers at delivery and in children both aged 1 and 3 years (adjusted odds ratio [aOR] and 95% confidence interval [CI]: 2.57 [1.14-5.78], 2.28 [1.02-5.13], respectively). The risk of childhood AR at the age of 3 is increased when both mothers and children have high eosiniophils (aOR and 95% CI: 2.62 [1.01-6.79], 1.37 [0.98-1.91]). CONCLUSIONS: Der f-IgE in mothers at delivery was related to eosinophil levels in mothers with AR and higher level of eosinophils in both mother and children was associated with the increased risk of AR incidence at the first 3 years of life of children.

Combined effect of hygienic and polygenic risk scores in children with allergic rhinitis.

BACKGROUND: Although the development of allergic rhinitis (AR) is associated with multiple genetic and hygienic environmental factors, previous studies have focused mostly on the effect of a single factor on the development of AR. OBJECTIVE: This study aimed to investigate the combined effect of multiple genetic and hygienic environmental risk factors on AR development in school children. METHODS: We conducted a cross-sectional study, comprising 1,797 children aged 9-12 years. Weighted environmental risk score (ERS) was calculated by using four hygienic environmental factors, including antibiotic use during infancy, cesarean section delivery, breast milk feeding, and having older siblings. Weighted polygenic risk score (PRS) was calculated by using four single nucleotide polymorphisms (SNPs), including interleukin-13 (rs20541), cluster of differentiation 14 (rs2569190), toll-like receptor 4 (rs1927911), and glutathione S-transferase P1 (rs1695). Multivariable logistic regression analysis was used. RESULTS: More than three courses of antibiotic use during infancy increased the risk of current AR (adjusted odd ratio [aOR], 2.058; 95% confidence interval [CI]: 1.290-3.284). Having older siblings, especially > 2 (aOR, 0.526; 95%Cl: 0.303-0.913) had a protective effect. High ERS ( > median; aOR, 2.079; 95%Cl: 1.466-2.947) and PRS ( > median; aOR, 1.627; 95%Cl: 1.117-2.370) increased the risk of current AR independently. Furthermore, children who had both high ERS and PRS showed a higher risk of current AR (aOR, 3.176; 95%Cl: 1.787-5.645). CONCLUSIONS: Exposure to multiple hygienic risk factors during infancy increases the risk of AR in genetically susceptible children.

Genome-wide multi-omics analysis reveals the nutrient-dependent metabolic features of mucin-degrading gut bacteria.

The prevalence and occurrence of mucin-degrading (MD) bacteria, such as Akkermansia muciniphila and Ruminococcus gnavus, is highly associated with human health and disease states. However, MD bacterial physiology and metabolism remain elusive. Here, we assessed functional modules of mucin catabolism, through a comprehensive bioinformatics-aided functional annotation, to identify 54 A. muciniphila genes and 296 R. gnavus genes. The reconstructed core metabolic pathways coincided with the growth kinetics and fermentation profiles of A. muciniphila and R. gnavus grown in the presence of mucin and its constituents. Genome-wide multi-omics analyses validated the nutrient-dependent fermentation profiles of the MD bacteria and identified their distinct mucolytic enzymes. The distinct metabolic features of the two MD bacteria induced differences in the metabolite receptor levels and inflammatory signals of the host immune cells. In addition, in vivo experiments and community-scale metabolic modeling demonstrated that different dietary intakes influenced the abundance of MD bacteria, their metabolic fluxes, and gut barrier integrity. Thus, this study provides insights into how diet-induced metabolic differences in MD bacteria determine their distinct physiological roles in the host immune response and the gut ecosystem.

NecroX Improves Polyhexamethylene Guanidine-induced Lung Injury by Regulating Mitochondrial Oxidative Stress and Endoplasmic Reticulum Stress.

Various environmental compounds are inducers of lung injury. Mitochondria are crucial organelles that can be affected by many lung diseases. NecroX is an indole-derived antioxidant that specifically targets mitochondria. We aimed to evaluate the therapeutic potential and related molecular mechanisms of NecroX in preclinical models of fatal lung injury. We investigated the therapeutic effects of NecroX on two different experimental models of lung injury induced by polyhexamethylene guanidine (PHMG) and bleomycin, respectively. We also performed transcriptome analysis of lung tissues from PHMG-exposed mice and compared the expression profiles with those from dozens of bleomycin-induced fibrosis public data sets. Respiratory exposure to PHMG and bleomycin led to fatal lung injury manifesting extensive inflammation followed by fibrosis. These specifically affected mitochondria regarding biogenesis, mitochondrial DNA integrity, and the generation of mitochondrial reactive oxygen species in various cell types. NecroX significantly improved the pathobiologic features of the PHMG- and bleomycin-induced lung injuries through regulation of mitochondrial oxidative stress. Endoplasmic reticulum stress was also implicated in PHMG-associated lung injuries of mice and humans, and NecroX alleviated PHMG-induced lung injury and the subsequent fibrosis, in part, via regulation of endoplasmic reticulum stress in mice. Gene expression profiles of PHMG-exposed mice were highly consistent with public data sets of bleomycin-induced lung injury models. Pathways related to mitochondrial activities, including oxidative stress, oxidative phosphorylation, and mitochondrial translation, were upregulated, and these patterns were significantly reversed by NecroX. These findings demonstrate that NecroX possesses therapeutic potential for fatal lung injury in humans.

Associations of prenatal antibiotic exposure and delivery mode on childhood asthma inception.

BACKGROUND: Prenatal antibiotic exposure and delivery mode may affect the gut microbiome in early life and influence the development of childhood asthma, but the combined effect of these 2 factors is unknown. OBJECTIVE: To identify the individual and combined effects of prenatal antibiotic exposure and delivery mode on the development of asthma in children and the potential mechanisms underlying these associations. METHODS: A total of 789 children from the Cohort for Childhood Origin of Asthma and Allergic Diseases birth cohort study were enrolled. Asthma was defined as a physician-confirmed diagnosis with asthma symptoms in the previous 12 months at age 7 years. Information on prenatal antibiotic exposure was obtained by mothers using a questionnaire. Logistic regression analysis was used. Gut microbiota analysis using 16S rRNA gene sequencing of fecal specimens obtained at 6 months was undertaken for 207 infants. RESULTS: Prenatal antibiotic exposure and cesarean section delivery (adjusted odds ratio [aOR], 95% confidence interval [CI], 5.70 [1.25-22.81] and 1.57 [1.36-6.14], respectively) were associated with childhood asthma, especially synergistically when compared with the vaginal delivery-prenatal antibiotic exposure reference group (aOR, 7.35; 95% CI, 3.46-39.61; Interaction P = .03). Prenatal antibiotic exposure was associated with childhood asthma with aORs 21.79 and 27.03 for 1 and 2 or more exposures, respectively. Considerable small-airway dysfunction (R5-R20 in impulse oscillometry) was observed with prenatal antibiotic exposure and cesarean section delivery, compared with those with spontaneous delivery without prenatal antibiotic exposure. There was no significant difference in the diversity of gut microbiota among the 4 groups. However, the relative abundance of Clostridium was significantly increased in infants with prenatal antibiotic exposure and delivered by means of cesarean section. CONCLUSION: Prenatal antibiotic exposure and delivery mode might modulate asthma development in children and small-airway dysfunction, potentially through early-life gut microbiota alterations.

The association between MTHFR polymorphism, dietary methyl donors, and childhood asthma and atopy.

BACKGROUND: Studies investigating the genetic association of the C677T methylenetetrahydrofolate reductase (MTHFR) genotype and dietary methyl donors with asthma and atopy are limited, and have variable results. OBJECTIVE: To investigate the effect of dietary methyl donor intake on the risk of childhood asthma and atopy, based on the C677T polymorphism in the MTHFR gene. METHODS: This cross-sectional study included 2,333 elementary school children aged 6-8 years across Korea during 2005 and 2006, as part of the first Children's Health and Environmental Research survey. Genotyping for the MTHFR (rs1801133) polymorphism was performed using the TaqMan assay. Multivariable-adjusted logistic regression analysis was performed to determine a descriptive association between the dietary methyl donor intake, MTHFR polymorphism, and childhood asthma and atopy. RESULTS: Intake of dietary methyl donors like folates was significantly associated with a decreased risk of the wheezing symptom, in the past 12 months, and "ever asthma" diagnosis, respectively. Vitamin B6 intake was also associated with a decreased atopy risk. The T allele of the MTHFR (rs1801133) gene was significantly associated with a decreased risk of atopy. Increased intakes of folate, vitamin B2, and vitamin B6 were protective factors against atopy, especially in children with the T allele on the MTHFR gene, compared to those with lower intakes and the CC genotype. CONCLUSIONS: High intakes of dietary methyl donors were associated with reduced risk of atopy and asthma symptoms. These may have additive effects related to the susceptibility alleles of the MTHFR gene. The clinical implications require evaluation.

Effects of dietary glycerol supplementation on meat quality, palatability, and lipid metabolism gene expression in the longissimus thoracis of Hanwoo steers.

This study tested the hypothesis that dietary glycerol supplementation (GS) would affect growth of Hanwoo steers, beef marbling and palatability, and gene expression for lipid uptake and transport and lipogenesis in the longissimus thoracis (LT). Diets with or without 45.2 g daily glycerol supplementation/kg dry matter concentrate were tested in fourteen Hanwoo steers during a 16-week feeding trial. GS did not affect (P ≥ 0.40) the average daily gain or the gain-to-feed ratio. GS increased the LT marbling score (P = 0.01). GS enhanced (P ≤ 0.01) the sensory traits, including the flavor and overall acceptance of the LT. GS tended (0.05 < P ≤ 0.10) to upregulate mRNA levels of fatty acid translocase, lipoprotein lipase, and fatty acid binding protein 4 genes in the LT. These tendencies of upregulated expression of fatty acid uptake and cytosolic transport genes may, in part, contribute to the increased marbling by GS. The increased marbling degree caused by GS may improve palatability including the flavor and overall acceptance of the LT.

Clinical characteristics of pediatric patients infected with SARS-CoV-2 versus common human coronaviruses: a national multicenter study.

BACKGROUND: Human coronaviruses (HCoV) cause mild upper respiratory infections; however, in 2019, a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged, causing an acute respiratory disease pandemic. Coronaviruses exhibit marked epidemiological and clinical differences. PURPOSE: This study compared the clinical, laboratory, and radiographic findings of children infected with SARS-CoV-2 versus HCoV. METHODS: SARS-CoV-2 data were obtained from the Korea Disease Control and Prevention Agency (KDCA) registry and 4 dedicated coronavirus disease 2019 (COVID-19) hospitals. Medical records of children admitted with a single HCoV infection from January 2015 to March 2020 were collected from 10 secondary/tertiary hospitals. Clinical data included age, sex, underlying disease, symptoms, test results, imaging findings, treatment, and length of hospital stay. RESULTS: We compared the clinical characteristics of children infected with HCoV (n=475) to those of children infected with SARS-CoV-2 (272 from KDCA, 218 from COVID-19 hospitals). HCoV patients were younger than KDCA patients (older than 9 years:3.6% vs. 75.7%; P<0.001) and patients at COVID-19 hospitals (2.0±2.9 vs 11.3±5.3; P<0.001). Patients with SARS-CoV-2 infection had a lower rate of fever (26.6% vs. 66.7%; P<0.001) and fewer respiratory symptoms than those with HCoV infection. Clinical severity, as determined by oxygen therapy and medication usage, was worse in children with HCoV infection. Children and adolescents with SARS-CoV-2 had less severe symptoms. CONCLUSION: Children and adolescents with COVID-19 had a milder clinical course and less severe disease than those with HCoV in terms of symptoms at admission, examination findings, and laboratory and radiology results.

Prenatal maternal anxiety promotes atopic dermatitis in offspring via placental DNA methylation changes.

BACKGROUND: Maternal anxiety during pregnancy has been previously reported to be associated with atopic dermatitis (AD) in offspring. The potential mechanism is not yet proven but epigenetic change may be suggested. OBJECTIVE: We examined whether maternal anxiety during pregnancy may alter placental DNA methylation, then develop AD in the offspring. METHODS: We evaluated maternal anxiety at 36 weeks of gestation by self-reported questionnaires, the State-Trait Anxiety Inventory-Trait subscale (STAI-T), in the Cohort for Childhood Origin of Asthma and Allergic Diseases (COCOA) study. AD was diagnosed at 6 months of age by pediatric allergists. We stratified the subjects into four groups according to the STAI score of mothers and diagnosis of AD in children. Placental genome-wide methylation microarray was analyzed using Infinium 450K BeadChip and selected genes were validated by pyrosequencing. RESULTS: From microarray, several differential methylation sites were identified in AD and healthy subjects and in total subjects, regarding to the STAI scores. Among differential methylation sites in microarray, six sites were selected for pyrosequencing. And site of matrix metalloproteinases 27 (MMP27) among 6 sites showed decreased methylation in AD infants with high STAI mothers compared to healthy infants with low STAI mothers. CONCLUSIONS: Epigenetic change in placenta can be a suggesting mechanism for the development of AD in offspring at 6 months of age associated with maternal anxiety during pregnancy and MMP27 may be a candidate gene.