The potential pathways underlying the association of propyl-paraben exposure with aeroallergen sensitization and EASI score using metabolomics analysis

Urinary Paraben Concentrations and Associations with the Periconceptional Urinary Metabolome: Untargeted and Targeted Metabolomics Analyses of Participants from the Early Pregnancy Study

BACKGROUND

Parabens, found in everyday items from personal care products to foods, are chemicals with endocrine-disrupting activity, which has been shown to influence reproductive function.

OBJECTIVES

This study investigated whether urinary concentrations of methylparaben, propylparaben, or butylparaben were associated with the urinary metabolome during the periconceptional period, a critical window for female reproductive function. Changes to the periconceptional urinary metabolome could provide insights into the mechanisms by which parabens could impact fertility.

METHODS

Urinary paraben concentrations were measured in paired pre- and postconception urine samples from 42 participants in the Early Pregnancy Study, a prospective cohort of 221 women attempting to conceive. We performed untargeted and targeted metabolomics analyses using ultrahigh-performance liquid chromatography quadrupole time-of-flight mass spectrometry. We used principal component analysis, orthogonal partial least-squares discriminant analysis, and permutation testing, coupled with univariate statistical analyses, to find metabolites associated with paraben concentration at the two time points. Potential confounders were identified with a directed acyclic graph and used to adjust results with multivariable linear regression. Metabolites were identified using fragmentation data.

RESULTS

Seven metabolites were associated with paraben concentration (variable importance to projection score > 1 , false discovery rate-corrected q -value < 0.1 ). We identified four diet-related metabolites to the Metabolomics Standards Initiative (MSI) certainty of identification level 2, including metabolites from smoke flavoring, grapes, and olive oil. One metabolite was identified to the class level only (MSI level 3). Two metabolites were unidentified (MSI level 4). After adjustment, three metabolites remained associated with methylparaben and propylparaben, two of which were diet-related. No metabolomic markers of endocrine disruption were associated with paraben concentrations.

DISCUSSION

This study identified novel relationships between urinary paraben concentrations and diet-related metabolites but not with metabolites on endocrine-disrupting pathways, as hypothesized. It demonstrates the feasibility of integrating untargeted metabolomics data with environmental exposure information and epidemiological adjustment for confounders. The findings underscore a potentially important connection between diet and paraben exposure, with applications to nutritional epidemiology and dietary exposure assessment. https://doi.org/10.1289/EHP12125.

Environmental phenol exposure associates with urine metabolome alteration in young Northeast Indian females

Urinary biomonitoring delivers the most accurate environmental phenols exposure assessment. However, environmental phenol exposure-related biomarkers are required to improve risk assessment to understand the internal processes perturbed, which may link exposure to specific health outcomes. This study aimed to investigate the association between environmental phenols exposure and the metabolome of young adult females from India. Urinary metabolomics was performed using liquid chromatography-mass spectrometry. Environmental phenols-related metabolic biomarkers were investigated by comparing the low and high exposure of environmental phenols. Seven potential biomarkers, namely histidine, cysteine-s-sulfate, 12-KETE, malonic acid, p-hydroxybenzoic acid, PE (36:2), and PS (36:0), were identified, revealing that environmental phenol exposure altered the metabolic pathways such as histidine metabolism, beta-Alanine metabolism, glycerophospholipid metabolism, and other pathways. This study also conceived an innovative strategy for the early prediction of diseases by combining urinary metabolomics with machine learning (ML) algorithms. The differential metabolites predictive accuracy by ML models was >80%. This is the first mass spectrometry-based metabolomics study on young adult females from India with environmental phenols exposure. The study is valuable in demonstrating multiple urine metabolic changes linked to environmental phenol exposure and a better understanding of the mechanisms behind environmental phenol-induced effects in young female adults.

Genetic/Environmental Contributions and Immune Dysregulation in Children with Atopic Dermatitis

Atopic dermatitis (AD) is one of the most common skin conditions in humans. AD affects up to 20% of children worldwide and results in morbidity for both patients and their caregivers. The basis of AD is an interplay between genetics and the environment characterized by immune dysregulation. A myriad of mutations that compromise the skin barrier and/or immune function have been linked to AD. Of these, filaggrin gene (FLG) mutations are the most evidenced. Many other mutations have been implicated in isolated studies that are often unreplicated, creating an archive of genes with potential but unconfirmed relevance to AD. Harnessing big data, polygenic risk scores (PRSs) and genome-wide association studies (GWAS) may provide a more practical strategy for identifying the genetic signatures of AD. Epigenetics may also play a role. Staphylococcus aureus is the most evidenced microbial contributor to AD. Cutaneous dysbiosis may result in over-colonization by pathogenic strains and aberrant skin immunity and inflammation. Aeroallergens, air pollution, and climate are other key environmental contributors to AD. The right climate and/or commensals may improve AD for some patients.

Serum parabens and its correlations with immunologic and cellular markers in Southern Taiwan industrialized city systemic lupus erythematosus patients

BACKGROUND

Although the immune systems of patients with systemic lupus erythematosus (SLE) are affected by both personal characteristics and environmental factors, the effects of parabens on patients with SLE have not been well studied. We investigated the indirect effects of four parabens-methylparaben (MP), ethylparaben (EP), propylparaben (n-PrP), and butylparaben (n-BuP)-on several immunological markers.

METHODS

We assessed the serum levels of MP, EP, n-PrP, and n-BuP in 25 SLE patients and correlated the concentration of each paraben with available clinical and laboratory markers, including intracellular markers of antiviral immunity and apoptosis.

RESULTS

The expression of aryl hydrocarbon receptor (AhR) was significantly negatively correlated with n-PrP levels (p = 0.03, r = -0.434). In monocytes, APO2.7 was significantly positively correlated with n-BuP levels (p = 0.019, r = 0.467). Glutathione levels were significantly negatively correlated with n-BuP levels (p = 0.019, r = -0.518). Anti- β2 glycoprotein I IgM was significantly positively correlated with both MP (p = 0.011, r = 0.585) and EP levels (p = 0.032, r = 0.506). Anti-cardiolipin IgA was significantly positively correlated with both MP (p = 0.038, r = 0.493) and n-PrP levels (p = 0.031, r = 0.508). On CD8 T cells, the early apoptotic marker annexin V was significantly negatively correlated with both MP (p < 0.05, r = -0.541) and n-BuP levels (p = 0.02, r = -0.616), and L-selectin was significantly positively correlated with both MP (p < 0.05, r = 0.47) and n-PrP levels (p = 0.02, r = 0.556).

CONCLUSION

Our findings suggest that higher parabens levels were associated with lower AhR expression in leukocytes, increased monocyte apoptosis, lower serum glutathione levels, reduced annexin V expression on CD8 T cells, and higher L-selectin levels on leukocytes.

Association between parabens concentrations in human amniotic fluid and the offspring birth size: A Sub-study of the PERSIAN birth cohort

OBJECTIVE

Parabens are extensively used, and cause widespread exposure of the general population including pregnant women and developing fetuses to these pollutants. In this study, we aimed to investigate the association between the maternal exposure of parabens to study their transfer passed through the placental barrier to amniotic fluid; the second objective was to determine the association of paraben concentration in the amniotic fluid with the offspring birth size.

METHODS

This cross-sectional study was conducted from June 2019 to March 2021 in Isfahan, Iran. Samples of amniotic fluid were collected as set from 128 pregnant women at Cesarean section. The amniotic fluid concentrations of four parabens including methylparaben (MP), ethylparaben (EP), propylparaben (PP), and butylparaben (BP) were determined using gas chromatography tandem mass spectroscopy (GC-Mass).

RESULTS

The pointed parabens were extracted from yielded clear supernatant using a dispersive liquid-liquid microextraction (DLLME) method. Four paraben derivatives including MP (normal: 0.68 ± 0.7; overweight: 1.40 ± 1.76; obese: 0.30 ± 0.26; p-value: 0.275), EP (normal: 0.14 ± 0.09; overweight: 0.72 ± 0.72; obese: 0.38 ± 0.05; p-value: 0.434), PP (normal: 0.05 ± 0.05; overweight: 0.06 ± 0.06; obese: 0.20 ± 0.17; p-value: 0.770), and BP (normal: 2.89 ± 1.80; overweight: 3.89 ± 6.48; obese: 5.80 ± 7.56; p-value: 0.341) were simultaneously detected in samples of maternal amniotic fluid using GC-MS. In 92.2% (n = 118) of pregnant women, the paraben derivatives (MP, EP, PP, BP) were detected. We found that considerable levels of MP, EP, PP, and BP existed in 22.6% (n = 29), 21.9% (n = 28), 29.7% (n = 38), and 85.2% (n = 109) of samples, respectively. In addition, the correlation between paraben concentrations in amniotic fluid and birth size was investigated. The results showed that an inverse significant association between MP and head circumference, chest, hip, and arm circumference. While a positive correlation between MP and height of newborn was observed. Similar correlations were observed for EP and weight, height, head circumference, chest, hip, and arm.

CONCLUSION

The current study indicated that parabens have been detected in amniotic fluid samples and a strong/possible correlation between exposure of pregnant women to parabens and the birth size of newborns.

An Overview of the Latest Metabolomics Studies on Atopic Eczema with New Directions for Study

Atopic eczema (AE) is an inflammatory skin disorder affecting approximately 20% of children worldwide and early onset can lead to asthma and allergies. Currently, the mechanisms of the disease are not fully understood. Metabolomics, the analysis of small molecules in the skin produced by the host and microbes, opens a window to observe the mechanisms of the disease which then may lead to new drug targets for AE treatment. Here, we review the latest advances in AE metabolomics, highlighting both the lipid and non-lipid molecules, along with reviewing the metabolites currently known to reside in the skin.

Current Knowledge in Skin Metabolomics: Updates from Literature Review

Metabolomic profiling is an emerging field consisting of the measurement of metabolites in a biological system. Since metabolites can vary in relation to different stimuli, specific metabolic patterns can be closely related to a pathological process. In the dermatological setting, skin metabolomics can provide useful biomarkers for the diagnosis, prognosis, and therapy of cutaneous disorders. The main goal of the present review is to present a comprehensive overview of the published studies in skin metabolomics. A search for journal articles focused on skin metabolomics was conducted on the MEDLINE, EMBASE, Cochrane, and Scopus electronic databases. Only research articles with electronically available English full text were taken into consideration. Studies specifically focused on cutaneous microbiomes were also excluded from the present search. A total of 97 papers matched all the research criteria and were therefore considered for the present work. Most of the publications were focused on inflammatory dermatoses and immune-mediated cutaneous disorders. Skin oncology also turned out to be a relevant field in metabolomic research. Only a few papers were focused on infectious diseases and rarer genetic disorders. All the major metabolomic alterations published so far in the dermatological setting are described extensively in this review.

Increased Prevalence of Atopic Dermatitis in Children Aged 0-3 Years Highly Exposed to Parabens

The prevalence of allergic diseases, such as bronchial asthma, atopic dermatitis, nasal allergies (pollinosis), and food allergies, has been increasing in many countries. The hygiene hypothesis was recently considered from the perspective of exposure to antimicrobial agents and preservatives, such as parabens (CAS number, 94-13-3). It currently remains unclear whether parabens, which are included in many daily consumer products such as cosmetics, shampoos, and personal care products as preservative antimicrobial agents, induce or aggravate allergies. Therefore, the aim of the present study was to examine the relationship between exposure to parabens and the prevalence of allergic diseases in Japanese children. The cross-sectional epidemiology of 236 children aged 0-3 years who underwent health examinations in Shika town in Japan assessed individual exposure to parabens using urinary concentrations of parabens. The results obtained showed that the prevalence of atopic dermatitis was significantly higher in children with high urinary concentrations of parabens than in those with low concentrations (p < 0.001). This relationship remained significant after adjustments for confounding factors, such as age, sex, Kaup's index, and passive smoking (p < 0.001). In conclusion, the present results from a population study suggested a relationship between atopic dermatitis and exposure to parabens. A longitudinal study using a larger sample number and a detailed examination of atopic dermatitis, including EASI scores and exposure to parabens, will be necessary.

Cumulative Risks of Excipients in Pediatric Phytomucolytic Syrups: The Implications for Pharmacy Practice

Expectorant phytomucolytic syrups are widely used pediatric OTC-medicines. Physicians, pediatricians, and pharmacists are traditionally concerned with the efficacy of the active ingredients in cough syrups, and rarely consider the safety aspects of excipients that however are not absolutely “inactive” and are proved to initiate some negative reactions and interactions with other drugs. This paper presents a review, categorization, and comparative analysis of the safety profile of excipients contained in the 22 best-selling OTC pediatric phytomucolytic syrups available in pharmaceutical markets in Ukraine and Germany and proposes an approach to the consideration of the excipients’ safety risks for a pharmacist in the process of pharmaceutical care. The study has revealed that only one of the twenty-two analyzed syrups does not contain any potentially harmful excipients. The results of this analysis were used for developing a specific decision tool for pharmacists that can be used for minimizing excipient-initiated reactions when delivering OTC phytomucolytic syrups for children.