Bisphenol A modified DNA: A possible immunogenic stimulus for anti-DNA autoantibodies in systemic lupus erythematosus

A targeted review on occurrence, remediation, and risk assessments of bisphenol A in Africa

Bisphenol A (BPA) is a vital raw material used to manufacture various household and commercial goods. However, BPA is a contaminant of emerging concern (CEC) and an endocrine-disrupting chemical (EDC) capable of migrating and bio-accumulating in environmental and biological compartments. At threshold levels, they become toxic causing adverse health and environmental issues. BPA's occurrence in food, food contact materials (FCMs), beverages, water, cosmetics, consumer goods, soil, sediments, and human/biological fluids across Africa was outlined. Unlike most reviews, it further collated data on BPA remediation techniques, including the human and ecological risk assessment studies conducted across Africa. A systematic scrutiny of the major indexing databases was employed extracting relevant data for this study. Results reveal that only 10 out of 54 countries have researched BPA in Africa. BPA levels in water were the most investigated, whereas levels in cosmetics and consumer goods were the least studied. Maximum BPA concentrations found in Africa were 3,590,000 ng/g (cosmetic and consumer goods), 154,820,000 ng/g (soils), 189 ng/mL (water), 1139 ng/g (food), and 208.55 ng/mL (biological fluids). The optimum percentage removal/degradation of BPA was within 70-100%. The potential health and ecological risk levels were assessed by comparing them with recommended limits and were found to fall within safe/low risks to unsafe/high risks. In conclusion, this study revealed that there is still little research on BPA in Africa. Levels detected in some matrices call for increased research, stricter health and environmental regulations, and surveillance.

Environmental triggers of autoimmunity: The association between bisphenol analogues and systemic lupus erythematosus

The aim of this research was to examine the correlation between the exposure to bisphenol analogues (BPs), such as bisphenol A (BPA), bisphenol F (BPF), and bisphenol S (BPS), and the risk of developing systemic lupus erythematosus (SLE). Ultra performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) was utilized to measure the levels of BPA, BPF, and BPS in the urine of 168 female participants diagnosed with SLE and 175 female participants who were deemed healthy controls. Logistic regression models were utilized to assess the connections between levels of bisphenol and the risk of SLE. The findings indicated that levels of BPA and BPF in the urine of individuals with SLE were markedly elevated compared to those in the control group. Higher exposure to BPA and BPF exhibited positive dose-response relationships with increased SLE risk. No significant associations were identified between BPS and the risk of SLE. These findings suggest exposure to BPA and BPF may be implicated as novel environmental triggers in the development of autoimmunity such as SLE. The significantly increased levels of these bisphenol analogues detected in SLE patients versus healthy controls, along with the associations between higher exposures and elevated SLE risk, which offers crucial hints for comprehending how endocrine-disrupting substances contribute to the genesis of autoimmune illnesses. Further research using robust longitudinal assessments of bisphenol analogue exposures is warranted to corroborate these epidemiological findings. Overall, this study highlights potential environmental risk factors for SLE while calling for additional investigation into the impact of bisphenol exposures on autoimmunity development.

Contributions of Synthetic Chemicals to Autoimmune Disease Development and Occurrence

PURPOSE OF REVIEW

Exposure to many synthetic chemicals has been linked to a variety of adverse human health effects, including autoimmune diseases. In this scoping review, we summarize recent evidence detailing the effects of synthetic environmental chemicals on autoimmune diseases and highlight current research gaps and recommendations for future studies.

RECENT FINDINGS

We identified 68 recent publications related to environmental chemical exposures and autoimmune diseases. Most studies evaluated exposure to persistent environmental chemicals and autoimmune conditions including rheumatoid arthritis (RA), systemic lupus (SLE), systemic sclerosis (SSc), and ulcerative colitis (UC) and Crohn's disease. Results of recent original research studies were mixed, and available data for some exposure-outcome associations were particularly limited. PFAS and autoimmune inflammatory bowel diseases (UC and CD) and pesticides and RA appeared to be the most frequently studied exposure-outcome associations among recent publications, despite a historical research focus on solvents. Recent studies have provided additional evidence for the associations of exposure to synthetic chemicals with certain autoimmune conditions. However, impacts on other autoimmune outcomes, particularly less prevalent conditions, remain unclear. Owing to the ubiquitous nature of many of these exposures and their potential impacts on autoimmune risk, additional studies are needed to better evaluate these relationships, particularly for understudied autoimmune conditions. Future research should include larger longitudinal studies and studies among more diverse populations to elucidate the temporal relationships between exposure-outcome pairs and to identify potential population subgroups that may be more adversely impacted by immune modulation caused by exposure to these chemicals.

Endocrine-disrupting chemicals and autoimmune diseases

Endocrine-disrupting chemicals (EDCs) widely exist in people's production and life which have great potential to damage human and animal health. Over the past few decades, growing attention has been paid to the impact of EDCs on human health, as well as immune system. So far, researchers have proved that EDCs (such as bisphenol A (BPA), phthalate, tetrachlorodibenzodioxin (TCDD), etc.) affect human immune function and promotes the occurrence and development of autoimmune diseases (ADs). Therefore, in order to better understand how EDCs affect ADs, we summarized the current knowledge about the impact of EDCs on ADs, and elaborated the potential mechanism of the impact of EDCs on ADs in this review.

A review on immunomodulatory effects of BPA analogues

Bisphenol A (BPA) is a known endocrine disruptor found in many consumer products that humans come into contact with on a daily basis. Due to increasing concerns about the safety of BPA and the introduction of new legislation restricting its use, industry has responded by adopting new, less studied BPA analogues that have similar polymer-forming properties. Some BPA analogues have already been shown to exhibit effects similar to BPA, for example, contributing to endocrine disruption through agonistic or antagonistic behaviour at various nuclear receptors such as estrogen (ER), androgen (AR), glucocorticoid (GR), aryl hydrocarbon (AhR), and pregnane X receptor (PXR). Since the European Food Safety Authority (EFSA) issued a draft re-evaluation of BPA and drastically reduced the temporary tolerable daily intake (t-TDI) of BPA from 4 mg/kg body weight/day to 0.2 ng/kg body weight/day due to increasing concern about the toxic properties of BPA, including its potential to disrupt immune system processes, we conducted a comprehensive review of the immunomodulatory activity of environmentally abundant BPA analogues. The results of the review suggest that BPA analogues may affect both the innate and acquired immune systems and can contribute to various immune-mediated conditions such as hypersensitivity reactions, allergies, and disruption of the human microbiome.

Increased levels of IL-17 and autoantibodies following Bisphenol A exposure were associated with activation of PI3K/AKT/mTOR pathway and abnormal autophagy in MRL/lpr mice

Bisphenol A (BPA) is a common environmental endocrine disruptor which mimic the effect of estrogen. The immunotoxicity of BPA has attracted widespread attention in recent years. However, the effects and mechanism of BPA on autoimmune disease were rarely reported. Systemic lupus erythematosus (SLE) is a typical autoimmune disease, and its etiology and mechanism are complex and unclear. Currently, inflammation and the production of autoantibodies are considered to be important pathological mechanisms of SLE, and estrogen contributes to the occurrence and development of SLE. Therefore, in order to explore whether BPA exposure can affect the development of SLE and its possible mechanism, we used MRL/lpr (lupus-prone mice) and C57/BL6 female mice exposed to 0.1 and 0.2 µg/mL BPA for 6 weeks. We discovered that BPA exposure increased the concentration of serum anti-dsDNA antibody and IL-17, and the level of RORγt protein (the transcription factor of Th17 cells). Moreover, there were higher expression of p-PI3K, p-AKT, p-mTOR, ULK, Rubicon, P62, Becline1 and LC3 protein in spleen tissue of BPA exposed MRL/lpr mice compared with the control. However, there were no significant changes in the expression of IL-17, RORγt or mTOR in C57 mice exposed to BPA at the same dose. Our study implied that BPA exposure induced the development of SLE, which might be related to the up-regulation of PI3K/AKT/mTOR signaling pathway and abnormal autophagy. Our study indicated that lupus mice were more susceptible to BPA, and provided a new insight into the mechanism by which BPA exacerbated SLE. Therefore, our study suggested that autoimmune patients and susceptible population should be considered when setting thresholds for environmental BPA exposure.

Toxoplasmosis in immunocompetent Saudi women: Correlation with vitamin D

Objective:

Toxoplasma gondii (T. gondii) is a life-threatening parasite particularly infecting the immunocompromised women. Deficiency of vitamin D is well reported in several infectious disorders. This study was undertaken to investigate a correlation of vitamin D deficiency with the onset of T. gondii infection in immunocompetent women from the central of Saudi Arabia.

Methods:

Blood samples were collected from 304 Saudi women from the Qassim region of Saudi Arabia. Specific immunoassays were used to determine the levels of T. gondii immunoglobulin G and vitamin D. The SPSS and the Prism Graph Pad statistical software were used for the data analysis.

Results:

Out of 304 women, 18.8% were found to be positive for toxoplasmosis. Interestingly, the serum levels of vitamin D in toxoplasma positive cases were found to be significantly low as compared with the levels of vitamin D in toxoplasma negative cases. Moreover, sociodemographic risk factors such as age, residence location, and consumption of fruits/vegetables were also found to be associated with vitamin D deficiency and with the seroprevalence of toxoplasmosis.

Conclusion:

This study investigated a direct correlation of vitamin D deficiency with the severity of the toxoplasmosis in Saudi women. Therefore, it is predicted that vitamin D supplementation may provide protection against toxoplasma infection.

ATP2B1 genotypes rs2070759 and rs2681472 polymorphisms and risk of hypertension in Saudi population

This study examined an association of ATP2B1 gene polymorphism and hypertension in the Saudi population. The 246 hypertensive cases and 300 healthy human controls were genotyped. The results showed that genotypes rs.207075 (CA + AA) [p = 0.05; OR: 95% CI, 1.5:(1.0 to 2.4) and p = 0.001, OR: 95% CI, 2.4: (1.5 to 4.0) and rs2681472 (CT + TT) [p = 0.05; OR: 95% CI, 1.5 (1.0 to 2.4) and p = 0.006 OR: 95% CI, 2.0 (1.2 to 3.1) respectively] associated with the risk of hypertension. Cases carrying the recessive models: [(CA + AA)/(CT + TT)] and [(AA)/(TT)] genotypes confer a strong susceptibility risk of hypertension [p = 0.002; OR: (95%CI) 1.8 (1.2 to 2.6) and p = 0.001; OR: (95%CI) 2.6 (1.5 to 4.7) respectively]. However, cases with body-mass-index (BMI)<25, carrying homozygous mutant genotypes [AA, rs2070759, p = 0.007; OR: (95%CI) 2.75(1.37 to 5.5) and (TT, rs2681472, p = 0.05; OR: (95%CI) 1.96 (1.03 to 3.72)] as well as A allele of rs2070759 [p = 0.006; OR: (95%CI) 1.62 (1.16 to 2.25)] and T allele of rs2681472, p = 0.04, 1.43(1.03 to 1.98)] showed a significant association with high risk of hypertension. In short, a significant association between ATP2B1 gene polymorphism and risk of hypertension was noticed. In addition, individuals carrying recessive genotypes have greater risk in developing hypertension than those carrying dominant genotypes. Moreover, cases with high-risk BMI associated with ATP2B1 variants may play a critical role in developing hypertension.Supplemental data for this article is available online at https://doi.org/10.1080/15257770.2021.1973034 .

Autoimmunity in 2019

Based on the PubMed data, we have been performing a yearly evaluation of the publications related to autoimmune diseases and immunology to ascertain the relative weight of the former in the scientific literature. It is particularly intriguing to observe that despite the numerous new avenues of immune-related mechanisms, such as cancer immunotherapy, the proportion of immunology manuscripts related to autoimmunity continues to increase and has been approaching 20% in 2019. As in the previous 13 years, we performed an arbitrary selection of the peer-reviewed articles published by the major dedicated Journals and discussed the common themes which continue to outnumber peculiarites in autoimmune diseases. The investigated areas included systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), psoriatic arthritis (PsA), autoantibodies (autoAbs), and common therapeutic avenues and novel pathogenic mechanisms for autoimmune conditions. Some examples include new pathogenetic evidence which is well represented by IL21 or P2X7 receptor (P2X7R) in SLE or the application of single-cell RNA sequencing (scRNA-seq), mass cytometry, bulk RNA sequencing (RNA-seq), and flow cytometry for the analysis of different cellular populations in RA. Cumulatively and of interest to the clinicians, a large number of findings continue to underline the importance of a strict relationship between basic and clinical science to define new pathogenetic and therapeutic developments. The therapeutic pipeline in autoimmunity continues to grow and maintain a constant flow of new molecules, as well illustrated in RA and PsA, and this is most certainly derived from the new basic evidence and the high-throughput tools applied to autoimmune diseases.

Protective Potential of Uric Acid, Folic Acid, Glutathione and Ascorbic Acid Against the Formation of Toxic Met-Myoglobin

BACKGROUND

Myoglobin is an oxygen binding protein and its dysfunction has been associated with the pathology of several human disorders. This study was undertaken to investigation the role of hydrogen peroxide (H2O2) in the formation of met-myoglobin and the protective potential of four different reductants such as uric acid, folic acid, glutathione and ascorbic acid were also tested against met-myoglobin formation.

METHODS

Human myoglobin was treated with H2O2 in-vitro in order to prepare met-myoglobin. The generation of met-myoglobin was confirmed by UV-visible spectroscopy and its stability was analysed by the treatment of human myoglobin with H2O2 at varying pH or time. High performance liquid chromatography (HPLC) was used to determine the oxidatively modified heme products in met-myoglobin. Spectroscopic analysis was used to identify the protective potential of uric acid, folic acid, glutathione and ascorbic acid against the formation of met-myoglobin.

RESULTS

The novel data of this study showed that H2O2 induced extensive damage of myoglobin but the treatment with uric acid, folic acid, glutathione or ascorbic acid provides protection of myoglobin against H2O2 induced oxidative damaged. The study apparently proved the protective potential of all these compounds against the toxicity produced by H2O2.

CONCLUSION

This is the first study that shows uric acid, folic acid, glutathione and ascorbic acid provide protection against the generation of toxic met-myoglobin and might be used therapeutically to modify the blood conditions in order to prevent the progression of human disorders associated with myoglobin dysfunction.

Bisphenol A as a Factor in the Mosaic of Autoimmunity

The population worldwide is largely exposed to bisphenol A (BPA), a commonly used plasticizer, that has a similar molecular structure to endogenous estrogens. Therefore, it is able to influence physiological processes in human body, taking part in the pathophysiology of various endocrinopathies, as well as, cardiovascular, neurological and oncological diseases. BPA has been found to affect the immune system, leading to the development of autoimmunity and allergies, too. In the last few decades, the prevalence of autoimmune diseases has significantly increased, that could be explained by a rising exposure of the population to environmental factors, such as BPA. BPA has been found to play a role in the pathogenesis of systemic autoimmune diseases and also organ-specific autoimmunity (thyroid autoimmunity, diabetes mellitus type 1, myocarditis, inflammatory bowel disease, multiple sclerosis, encephalomyelitis etc), but the results of some studies remain still controversial, so further research is needed.

Interplay Between Endocrine Disruptors and Immunity: Implications for Diseases of Autoreactive Etiology

The sex-bias of disease susceptibility has remained a puzzling aspect of several autoimmune conditions, including post-infection viral autoimmunity. In the last half of the twentieth century, the incidence rate of female-biased autoimmunity has steadily increased independent of medical advances. This has suggested a role for environmental factors, such as endocrine disrupting chemicals, which have been described to interfere with endocrine signaling. Endocrine involvement in the proper function of innate and adaptive immunity has also been defined, however, these two areas have rarely been reviewed in correlation. In addition, studies addressing the effects of endocrine disruptors have reported findings resulting from a broad range of exposure doses, schedules and models. This experimental heterogeneity adds confusion and may mislead the translation of findings to human health. Our work will normalize results across experiments and provide a necessary summary relevant to human exposure. Through a novel approach, we describe how different categories of ubiquitously used environmental endocrine disruptors interfere with immune relevant endocrine signaling and contribute to autoimmunity. We hope this review will guide identification of mechanisms and concentration-dependent EDC effects important not only for the sex-bias of autoimmunity, but also for other conditions of immune dysfunction, including post-infection autoreactivity such as may arise following severe acute respiratory syndrome coronavirus 2, Epstein-Barr virus, Herpes Simplex virus.

Missense, silent, non-sense and frame-shift mutations in exon 3 of the filaggrin gene in patients with bronchial asthma, atopic dermatitis, allergic rhinitis and mixed atopy

This study investigated the atopic march on the basis of genetics. This research detected 227 variants in the filaggrin gene (FLG gene). Missense, silent, non-sense, frame-shift and non-coding mutations were detected in exon 3 of the FLG gene in patients with bronchial asthma, atopic dermatitis, allergic rhinitis and mixed atopy. Missense mutation was detected at c.8343 G > C (p. Asp2781Glu) in all adult asthmatic and allergic rhinitis patients. Whereas, mutation at c.8360 C > T/A (p. Arg2787 His/Leu) was detected in all childhood asthmatic and mixed atopic patients. A non-coding mutation was detected at c.12365 in atopic dermatitis and bronchial asthma patients. Furthermore, DNA sequencing of asthmatic and mixed atopic patients showed missense mutations at c.6073 C > T (p. Gly2025Glu) and a silent mutation at c. 8341 G > A (p. Asp2781Asp).

TNF-α - 308 G/A and IFN-γ + 874 A/T gene polymorphisms in Saudi patients with cutaneous leishmaniasis

BACKGROUND

Cutaneous leishmaniasis (CL) is well linked with immunogenetic factors. This study was undertaken to test the association of TNF-α - 308 and IFN-γ + 874 gene polymorphisms with the susceptibility of Leishmania (L) species among CL patients in central region of Saudi Arabia.

METHODS

This is a case-control study involved 169 Saudi subjects with different L. species and 199 healthy controls from central region of Saudi Arabia. All subjects were characterized by TNF-α - 308 G/A and IFN-γ + 874 A/T gene polymorphisms using PCR.

RESULTS

Evaluation of genotyping and allelic frequency of TNF-α - 308 G/A in different L. species showed no significant association compared to controls (p > 0.05). Except, in cases of L. tropica that showed significantly higher TNF-α - 308 A versus G allele frequency (p = 0.0004). Evaluation of genotyping of IFN-γ + 874 (TT versus AA+AT recessive) and allelic frequency of IFN-γ + 874 (T versus A) showed significant higher in L. major and also in total CL cases as compared to healthy controls (p < 0.05). Furthermore, a strong association was observed between the susceptibility of L. major, L. tropica or total CL cases with synergistically combined high TNF-α 308/INF-γ 874 alleles.

CONCLUSIONS

This is the first report that shows the gene polymorphisms of TNF-α - 308 G/A and IFN-γ + 874 A/T in Saudi patients with different L. species infections. Data showed that the TNF-α-308 G/A gene polymorphism is not associated with the susceptibility of CL in Saudi subjects. The only correlation was found in between A versus G allelic frequency in L. tropica. Importantly, IFN-γ + 874 A/T polymorphism was found to be associated with the susceptibility of L. major and also with total CL subjects. Moreover, data from synergistically combined high TNF-α 308/INF-γ 874 alleles strongly suggest their potential role in the susceptibility of leishmania infection.

Maternal environmental exposure to bisphenols and epigenome-wide DNA methylation in infant cord blood

Maternal prenatal exposures, including bisphenol A (BPA), are associated with offspring's risk of disease later in life. Alterations in DNA methylation may be a mechanism through which altered prenatal conditions (e.g. maternal exposure to environmental toxicants) elicit this disease risk. In the Michigan Mother and Infant Pairs Cohort, maternal first-trimester urinary BPA, bisphenol F, and bisphenol S concentrations were tested for association with DNA methylation patterns in infant umbilical cord blood leukocytes (N = 69). We used the Illumina Infinium MethylationEPIC BeadChip to quantitatively evaluate DNA methylation across the epigenome; 822 020 probes passed pre-processing and quality checks. Single-site DNA methylation and bisphenol models were adjusted for infant sex, estimated cell-type proportions (determined using cell-type estimation algorithm), and batch as covariates. Thirty-eight CpG sites [false discovery rate (FDR) <0.05] were significantly associated with maternal BPA exposure. Increasing BPA concentrations were associated with lower DNA methylation at 87% of significant sites. BPA exposure associated DNA methylation sites were enriched for 38 pathways significant at FDR <0.05. The pathway or gene-set with the greatest odds of enrichment for differential methylation (FDR <0.05) was type I interferon receptor binding. This study provides a novel understanding of fetal response to maternal bisphenol exposure through epigenetic change.