Immunomodulatory effects of environmental endocrine disrupting chemicals

Efficient removal of 17α-ethinylestradiol (EE2) from water using freshly formed Fe–Mn binary oxide

The removal mechanism of EE2: adsorption onto FMBO through hydrogen bonding and then oxidation by MnO₂.

Maternal inflammatory bowel disease and hypospadias in male offspring: a population-based study in Denmark

Background

The occurrence of inflammatory bowel disease (IBD) and hypospadias has been concurrently increasing, possibly through shared environmental risk factors such as endocrine disrupting compounds. Also, maternal IBD may disturb the normal development of the fetal reproductive tract. However, whether maternal IBD increases the risk of hypospadias in male offspring is unknown. We compared hypospadias risk in sons of mothers with and without IBD.

Methods

We used Danish nationwide population-based registries to conduct a longitudinal prevalence study including all live-born boys from 1979 through 2009. We computed HRs, as estimates of prevalence ratios (PRs), with 95% CIs for hypospadias, using Cox proportional hazards regression, while adjusting for measured confounding.

Results

Among 966 038 live-born boys, 4688 (0.5%) had a mother with a history of IBD diagnosis before the relevant childbirth. Among the boys with maternal IBD, 36 (0.8%) were diagnosed with hypospadias any time after birth, whereas 6112 (0.6%) sons of mothers without IBD diagnosis had hypospadias (adjusted PR: 1.20, (95% CI 0.86 to 1.67). Adjusted PRs for maternal Crohn's disease and ulcerative colitis were 1.38 (95% CI 0.83 to 2.29) and 1.10 (95% CI 0.71 to 1.68), respectively. Analyses defining hypospadias diagnosis recorded <6 months postpartum showed similar results.

Conclusions

We found no convincing evidence of an association between maternal IBD and hypospadias.

Developmental Bisphenol A Exposure Modulates Immune-Related Diseases

Bisphenol A (BPA), used in polycarbonate plastics and epoxy resins, has a widespread exposure to humans. BPA is of concern for developmental exposure resulting in immunomodulation and disease development due to its ability to cross the placental barrier and presence in breast milk. BPA can use various mechanisms to modulate the immune system and affect diseases, including agonistic and antagonistic effects on many receptors (e.g., estrogen receptors), epigenetic modifications, acting on cell signaling pathways and, likely, the gut microbiome. Immune cell populations and function from the innate and adaptive immune system are altered by developmental BPA exposure, including decreased T regulatory (Treg) cells and upregulated pro- and anti-inflammatory cytokines and chemokines. Developmental BPA exposure can also contribute to the development of type 2 diabetes mellitus, allergy, asthma and mammary cancer disease by altering immune function. Multiple sclerosis and type 1 diabetes mellitus may also be exacerbated by BPA, although more research is needed. Additionally, BPA analogs, such as bisphenol S (BPS), have been increasing in use, and currently, little is known about their immune effects. Therefore, more studies should be conducted to determine if developmental exposure BPA and its analogs modulate immune responses and lead to immune-related diseases.

Low-dose exposure to di-(2-ethylhexyl) phthalate (DEHP) increases susceptibility to testicular autoimmunity in mice

Exposure to di-(2-ethylhexyl) phthalate (DEHP) induces spermatogenic disturbance (SD) through oxidative stress, and affects the immune system by acting as an adjuvant. Recently, we reported that in mice, a low dose of DEHP, which did not affect spermatogenesis, was able to alter the testicular immune microenvironment. Experimental autoimmune orchitis (EAO) can be induced by repeated immunization with testicular antigens, and its pathology is characterized by production of autoantibodies and SD. In the present study, we investigated the effect of a low-dose DEHP on the susceptibility of mice to EAO. The exposure to DEHP-containing feed (0.01%) caused a modest functional damage to the blood-testis barrier (BTB) with an increase in testicular number of interferon gamma (IFN-γ)-positive cells and resulted in the production of autoantibodies targeting haploid cells, but did not affect spermatogenesis. While only single immunization with testicular antigens caused very mild EAO, the concurrent DEHP exposure induced severe EAO with significant increases in number of interferon gamma-positive cells and macrophages, as well as lymphocytic infiltration and serum autoantibody titer accompanied by severe SD. To summarize, the exposure of mice to the low-dose DEHP does not induce significant SD, but it may cause an increase in IFN-γ positive cells and modest functional damage to the BTB in the testis. These changes lead to an autoimmune response against haploid cell autoantigens, resulting in increased susceptibility to EAO.

Chemical compounds from anthropogenic environment and immune evasion mechanisms: potential interactions

An increasing number of studies suggest an important role of host immunity as a barrier to tumor formation and progression. Complex mechanisms and multiple pathways are involved in evading innate and adaptive immune responses, with a broad spectrum of chemicals displaying the potential to adversely influence immunosurveillance. The evaluation of the cumulative effects of low-dose exposures from the occupational and natural environment, especially if multiple chemicals target the same gene(s) or pathway(s), is a challenge. We reviewed common environmental chemicals and discussed their potential effects on immunosurveillance. Our overarching objective was to review related signaling pathways influencing immune surveillance such as the pathways involving PI3K/Akt, chemokines, TGF-β, FAK, IGF-1, HIF-1α, IL-6, IL-1α, CTLA-4 and PD-1/PDL-1 could individually or collectively impact immunosurveillance. A number of chemicals that are common in the anthropogenic environment such as fungicides (maneb, fluoxastrobin and pyroclostrobin), herbicides (atrazine), insecticides (pyridaben and azamethiphos), the components of personal care products (triclosan and bisphenol A) and diethylhexylphthalate with pathways critical to tumor immunosurveillance. At this time, these chemicals are not recognized as human carcinogens; however, it is known that they these chemicalscan simultaneously persist in the environment and appear to have some potential interfere with the host immune response, therefore potentially contributing to promotion interacting with of immune evasion mechanisms, and promoting subsequent tumor growth and progression.

Water-compatible magnetic imprinted nanoparticles served as solid-phase extraction sorbents for selective determination of trace 17beta-estradiol in environmental water samples by liquid chromatography

Endocrine disrupting compounds (EDCs) are a potential risk for wildlife and humans for their existence in water. The efficient extraction and clean-up steps are required before detection of low concentration levels of EDCs. In this work, a novel water-compatible magnetic molecularly imprinted nanoparticles is synthesized for the selective extraction of 17β-estradiol (E2) in environmental water samples. The preparation is carried out by introducing aldehyde groups to the surface of amino-functionalized magnetic nanoparticles through a simple one-step modification, followed by copolymerization of functional monomer gelatin and template E2 via surface imprinting technique. The gelatin with abundant active groups could not only act as functional monomer reacting with template, but also assemble covalently at the surface of magnetic nanoparticles. At the same time, gelatin would improve the water-compatibility of imprinted materials for attaining high extraction efficiency. To obtain high imprinting effect, the preparation conditions are optimized in detail using Central composite design-response surface methodology. The resultant polymers have uniform spherical shape with a shell thickness of about 8nm, stable crystalline form, and super-paramagnetic property. Meanwhile, the obtained polymers have high capacity of 12.87mgg(-1) and satisfactory selectivity to template molecule. To testify the feasibility of the magnetic imprinted polymers in sample pretreatment, a method for determination of trace E2 in environmental water samples was set up by combination of solid-phase extraction (SPE) using the prepared polymers as sorbents and HPLC for rapid isolation and determination of E2. The limit of detection of proposed method is 0.04ngmL(-1), the intra- and inter-day relative standard deviations (RSDs) are less than 4.6% and 5.7%, respectively. The recoveries of E2 from environmental water samples are in the range from 88.3% to 99.1% with the RSDs less than 7.2%.

Autism spectrum disorders in children of parents with inflammatory bowel disease - a nationwide cohort study in Denmark

PURPOSE

Inflammatory bowel disease (IBD) and autism spectrum disorders (ASD) may share genetic and environmental risk factors. We examined whether parental IBD is associated with an increased risk of ASD in offspring.

METHODS

We conducted a registry-based nationwide cohort study including children born alive in Denmark from January 1, 1994 to December 31, 2009, with follow-up throughout 2010. IBD in parents and ASD in offspring were identified using inpatient and outpatient hospital diagnoses. We computed risk of ASD and crude and adjusted incidence rate ratios (aIRRs) with 95% confidence intervals (CI) using Cox proportional-hazards regression. We evaluated the risk of ASD according to maternal and paternal IBD, and separately for maternal and paternal Crohn's disease (CD) and ulcerative colitis (UC). Children with parents free of IBD were the comparison cohort.

RESULTS

We identified 1,005,330 children during the study period. Among them, 11,888 (1.2%) had a parent with IBD and 8,087 (0.8%) had a diagnosis of ASD during up to 17 years of follow-up. The 10-year risks of ASD were 0.7% among children of parents with IBD and 0.9% among children of parents without IBD. The aIRR for ASD among children with parental IBD was 0.8 (95% CI: 0.6-1.0), and results were similar regardless of parent of IBD origin or whether a parent had CD or UC. The estimates were similar for different ASD subtypes.

CONCLUSION

We found no evidence of an increased risk of ASD among children born to parents with IBD.

Assessment of a dielectric barrier discharge plasma reactor at atmospheric pressure for the removal of bisphenol A and tributyltin

The ability of a laboratory-scale dielectric barrier discharge (DBD) nonthermal plasma reactor at atmospheric pressure was assessed for the removal of bisphenol A (1 mg L(-1)) and tributyltin (10 mg L(-1)) from aqueous solutions. The elimination of both the compounds followed an exponential decay equation, and a first-order degradation kinetics was proposed for them (k = 0.662 min(-1) for bisphenol A and k = 0.800 min(-1) for tributyltin), reaching in both cases about 96% removal after 5-min treatment. Accordingly, plasma DBD reactors could be used as alternative advanced oxidation technologies for the removal of some persistent and toxic pollutants from water and wastewater, although further research should be performed to evaluate the effluent toxicity.

Parental inflammatory bowel disease and risk of asthma in offspring: a nationwide cohort study in denmark

OBJECTIVES:

Common genetic and environmental risk factors may explain the concurrent increase in the incidence of both inflammatory bowel disease (IBD) and asthma. We examined whether IBD in a parent is associated with an increased asthma risk in offspring.

METHODS:

This was a registry-based cohort study of all children born alive in Denmark in 1979–2009, followed through 2010. IBD and asthma were identified using hospital diagnoses; antiasthma medication was also used to identify asthma. We computed risk of asthma and estimated adjusted incidence rate ratios (aIRRs) with 95% confidence intervals (CIs) using Cox proportional-hazards regression. We evaluated asthma risk according to maternal and paternal IBD, Crohn's disease (CD), and ulcerative colitis (UC). Children without parental IBD were the comparison cohort for all comparisons.

RESULTS:

We identified 1,845,281 children, of whom 14,952 (0.8%) had a parent with IBD. The 10-year risk of asthma was 6.9% among offspring of parents with CD, 5.6% among offspring of parents with UC, and 5.0% among offspring of parents without IBD. The aIRR for asthma associated with parental IBD was 0.98 (95% CI: 0.91–1.04). The aIRR was 1.09 (95% CI: 0.98–1.22) for parental CD and 0.92 (95% CI: 0.84–1.00) for parental UC. Results were similar regardless of parent of origin or inclusion of antiasthma medication to define asthma.

CONCLUSIONS:

Our data do not provide evidence for an increased risk of asthma in offspring with a parental history of IBD.

Early life exposure to antibiotics and the risk of childhood allergic diseases: an update from the perspective of the hygiene hypothesis

The prevalence of allergic diseases has been growing rapidly in industrial countries during recent decades. It is postulated that growing up with less microbial exposure may render the immune system susceptible to a T helper type 2 (Th2)-predominant allergic response-also known as the hygiene hypothesis. This review delineates recent epidemiological and experimental evidence for the hygiene hypothesis, and integrates this hypothesis into the association between early life exposure to antibiotics and the development of allergic diseases and asthma. Several retrospective or prospective epidemiological studies reveal that early exposure to antibiotics may be positively associated with the development of allergic diseases and asthma. However, the conclusion is inconsistent. Experimental studies show that antibiotics may induce the Th2-skewed response by suppressing the T helper type 1 (Th1) response through inhibition of Th1 cytokines and disruption of the natural course of infection, or by disturbing the microflora of the gastrointestinal (GI) tract and therefore jeopardizing the establishment of oral tolerance and regulatory T cell immune responses. The hygiene hypothesis may not be the only explanation for the rapid increase in the prevalence of allergic diseases and asthma. Further epidemiological and experimental studies addressing the issue of the impact of environmental factors on the development of allergic diseases and the underlying mechanisms may unveil novel strategies for the prevention and treatment of allergic diseases in the future.