The Impact of Arsenic Exposure on Whole Blood DNA Methylation: An Epigenome-Wide Study of Bangladeshi Adults

Abstract Background Between 1962 and 1971, the US Air Force sprayed Agent Orange across Vietnam, exposing many soldiers to this dioxin-containing herbicide. Several negative health outcomes have been linked to Agent Orange exposure, but data is lacking on the effects this chemical has on the genome. Therefore, we sought to characterize the impact of Agent Orange exposure on DNA methylation in the whole blood and adipose tissue of veterans enrolled in the Air Force Health Study (AFHS). Methods We received adipose tissue (n = 37) and whole blood (n = 42) from veterans in the AFHS. Study participants were grouped as having low, moderate, or high TCDD body burden based on their previously measured serum levels of dioxin. DNA methylation was assessed using the Illumina 450 K platform. Results Epigenome-wide analysis indicated that there were no FDR-significantly methylated CpGs in either tissue with TCDD burden. However, 3 CpGs in the adipose tissue (contained within SLC9A3, LYNX1, and TNRC18) were marginally significantly (q < 0.1) hypomethylated, and 1 CpG in whole blood (contained within PTPRN2) was marginally significantly (q < 0.1) hypermethylated with high TCDD burden. Analysis for differentially methylated DNA regions yielded SLC9A3, among other regions in adipose tissue, to be significantly differentially methylated with higher TCDD burden. Comparing whole blood data to a study of dioxin exposed adults from Alabama identified a CpG within the gene SMO that was hypomethylated with dioxin exposure in both studies. Conclusion We found limited evidence of dioxin associated DNA methylation in adipose tissue and whole blood in this pilot study of Vietnam War veterans. Nevertheless, loci in the genes of SLC9A3 in adipose tissue, and PTPRN2 and SMO in whole blood, should be included in future exposure analyses.

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DNA Methylation in the Adipose Tissue and Whole Blood of Agent Orange-exposed Operation Ranch Hand Veterans

10.21203/rs.3.rs-99596/v1 ◽

2020 ◽

Author(s):

Matthew Rae Rytel ◽

Rondi Butler ◽

Melissa Eliot ◽

Joseph M. Braun ◽

E. Andres Houseman ◽

...

Keyword(s):

Dna Methylation ◽

Adipose Tissue ◽

Vietnam War ◽

Air Force ◽

Whole Blood ◽

Body Burden ◽

Serum Levels ◽

Agent Orange ◽

Health Study ◽

The Impact

Abstract BackgroundBetween 1962 and 1971, the US Air Force sprayed Agent Orange across Vietnam, exposing many soldiers to this dioxin-containing herbicide. Several negative health outcomes have been linked to Agent Orange exposure, but data is lacking on the effects this chemical has on the genome. Therefore, we sought to characterize the impact of Agent Orange exposure on DNA methylation in the whole blood and adipose tissue of veterans enrolled in the Air Force Health Study (AFHS). MethodsWe received adipose tissue (n=37) and whole blood (n=42) from veterans in the AFHS. Study participants were grouped as having low, moderate, or high TCDD body burden based on their previously measured serum levels of dioxin. DNA methylation was assessed using the Illumina 450K platform.ResultsEpigenome-wide analysis indicated that there were no FDR-significantly methylated CpGs in either tissue with TCDD burden. However, 3 CpGs in the adipose tissue (contained within SLC9A3, LYNX1, and TNRC18) were marginally significantly (q<0.1) hypomethylated, and 1 CpG in whole blood (contained within PTPRN2) was marginally significantly (q<0.1) hypermethylated with high TCDD burden. Analysis for differentially methylated DNA regions yielded SLC9A3, among other regions in adipose tissue, to be significantly differentially methylated with higher TCDD burden. Comparing whole blood data to a study of dioxin exposed adults from Alabama identified a CpG within the gene SMO that was hypomethylated with dioxin exposure in both studies. ConclusionWe found limited evidence of dioxin associated DNA methylation in adipose tissue and whole blood in this pilot study of Vietnam War veterans. Nevertheless, loci in the genes of SLC9A3 in adipose tissue, and PTPRN2 and SMO in whole blood, should be included in future exposure analyses.

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Maternal/fetal metabolomes appear to mediate the impact of arsenic exposure on birth weight: A pilot study

Journal of Exposure Science & Environmental Epidemiology ◽

10.1038/jes.2016.74 ◽

2016 ◽

Vol 27 (3) ◽

pp. 313-319 ◽

Cited By ~ 3

Author(s):

Yongyue Wei ◽

Qianwen Shi ◽

Zhaoxi Wang ◽

Ruyang Zhang ◽

Li Su ◽

...

Keyword(s):

Birth Weight ◽

Pilot Study ◽

Arsenic Exposure ◽

Impact Of Arsenic ◽

The Impact

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Association of Arsenic Exposure with Whole Blood DNA Methylation: An Epigenome-Wide Study of Bangladeshi Adults

Environmental Health Perspectives ◽

10.1289/ehp3849 ◽

2019 ◽

Vol 127 (5) ◽

pp. 057011 ◽

Cited By ~ 7

Author(s):

Kathryn Demanelis ◽

Maria Argos ◽

Lin Tong ◽

Justin Shinkle ◽

Mekala Sabarinathan ◽

...

Keyword(s):

Dna Methylation ◽

Whole Blood ◽

Arsenic Exposure

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Assessing the impact of arsenic metabolism efficiency on DNA methylation using Mendelian randomization

Environmental Epidemiology ◽

10.1097/ee9.0000000000000083 ◽

2020 ◽

Vol 4 (2) ◽

pp. e083

Author(s):

Anthony DiGiovanni ◽

Kathryn Demanelis ◽

Lin Tong ◽

Maria Argos ◽

Justin Shinkle ◽

...

Keyword(s):

Dna Methylation ◽

Mendelian Randomization ◽

Arsenic Metabolism ◽

Impact Of Arsenic ◽

The Impact

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Epigenetic Studies in Psychotherapy: A Systematic Review

Current Psychiatry Research and Reviews ◽

10.2174/2666082216999200622140922 ◽

2020 ◽

Vol 16 (2) ◽

pp. 86-92

Author(s):

Rafael Penadés ◽

Bárbara Arias ◽

Mar Fatjó-Vilas ◽

Laura González-Vallespí ◽

Clemente García-Rizo ◽

...

Keyword(s):

Systematic Review ◽

Dna Methylation ◽

Mental Disorders ◽

Epigenetic Modifications ◽

Symptom Improvement ◽

Epigenetic Changes ◽

Main Hypothesis ◽

Psychological Treatments ◽

Time Period ◽

The Impact

Background: Epigenetic modifications appear to be dynamic and they might be affected by environmental factors. The possibility of influencing these processes through psychotherapy has been suggested. Objective: To analyse the impact of psychotherapy on epigenetics when applied to mental disorders. The main hypothesis is that psychological treatments will produce epigenetic modifications related to the improvement of treated symptoms. Methods: A computerised and systematic search was completed throughout the time period from 1990 to 2019 on the PubMed, ScienceDirect and Scopus databases. Results: In total, 11 studies were selected. The studies were evaluated for the theoretical framework, genes involved, type of psychotherapy and clinical challenges and perspectives. All studies showed detectable changes at the epigenetic level, like DNA methylation changes, associated with symptom improvement after psychotherapy. Conclusion: Methylation profiles could be moderating treatment effects of psychotherapy. Beyond the detected epigenetic changes after psychotherapy, the epigenetic status before the implementation could act as an effective predictor of response.

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DNA methylome signatures of prenatal exposure to synthetic glucocorticoids in hippocampus and peripheral whole blood of female guinea pigs in early life

Translational Psychiatry ◽

10.1038/s41398-020-01186-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Aya Sasaki ◽

Margaret E. Eng ◽

Abigail H. Lee ◽

Alisa Kostaki ◽

Stephen G. Matthews

Keyword(s):

Dna Methylation ◽

Whole Blood ◽

Guinea Pigs ◽

Critical Role ◽

Methylation Status ◽

Peripheral Tissues ◽

Epigenetic Biomarkers ◽

Differentially Methylated Genes ◽

Increased Risk ◽

Synthetic Glucocorticoids

AbstractSynthetic glucocorticoids (sGC) are administered to women at risk of preterm delivery, approximately 10% of all pregnancies. In animal models, offspring exposed to elevated glucocorticoids, either by administration of sGC or endogenous glucocorticoids as a result of maternal stress, show increased risk of developing behavioral, endocrine, and metabolic dysregulation. DNA methylation may play a critical role in long-lasting programming of gene regulation underlying these phenotypes. However, peripheral tissues such as blood are often the only accessible source of DNA for epigenetic analyses in humans. Here, we examined the hypothesis that prenatal sGC administration alters DNA methylation signatures in guinea pig offspring hippocampus and whole blood. We compared these signatures across the two tissue types to assess epigenetic biomarkers of common molecular pathways affected by sGC exposure. Guinea pigs were treated with sGC or saline in late gestation. Genome-wide modifications of DNA methylation were analyzed at single nucleotide resolution using reduced representation bisulfite sequencing in juvenile female offspring. Results indicate that there are tissue-specific as well as common methylation signatures of prenatal sGC exposure. Over 90% of the common methylation signatures associated with sGC exposure showed the same directionality of change in methylation. Among differentially methylated genes, 134 were modified in both hippocampus and blood, of which 61 showed methylation changes at identical CpG sites. Gene pathway analyses indicated that prenatal sGC exposure alters the methylation status of gene clusters involved in brain development. These data indicate concordance across tissues of epigenetic programming in response to alterations in glucocorticoid signaling.

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Epigenome-wide association study of whole blood gene expression in Framingham Heart Study participants provides molecular insight into the potential role of CHRNA5 in cigarette smoking-related lung diseases

Clinical Epigenetics ◽

10.1186/s13148-021-01041-5 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Chen Yao ◽

Roby Joehanes ◽

Rory Wilson ◽

Toshiko Tanaka ◽

Luigi Ferrucci ◽

...

Keyword(s):

Gene Expression ◽

Lung Cancer ◽

Dna Methylation ◽

Cigarette Smoking ◽

Association Study ◽

Whole Blood ◽

Lung Diseases ◽

Epigenetic Modification ◽

Blood Gene Expression ◽

Increased Risk

Abstract Background DNA methylation is a key epigenetic modification that can directly affect gene regulation. DNA methylation is highly influenced by environmental factors such as cigarette smoking, which is causally related to chronic obstructive pulmonary disease (COPD) and lung cancer. To date, there have been few large-scale, combined analyses of DNA methylation and gene expression and their interrelations with lung diseases. Results We performed an epigenome-wide association study of whole blood gene expression in ~ 6000 individuals from four cohorts. We discovered and replicated numerous CpGs associated with the expression of cis genes within 500 kb of each CpG, with 148 to 1,741 cis CpG-transcript pairs identified across cohorts. We found that the closer a CpG resided to a transcription start site, the larger its effect size, and that 36% of cis CpG-transcript pairs share the same causal genetic variant. Mendelian randomization analyses revealed that hypomethylation and lower expression of CHRNA5, which encodes a smoking-related nicotinic receptor, are causally linked to increased risk of COPD and lung cancer. This putatively causal relationship was further validated in lung tissue data. Conclusions Our results provide a large and comprehensive association study of whole blood DNA methylation with gene expression. Expression platform differences rather than population differences are critical to the replication of cis CpG-transcript pairs. The low reproducibility of trans CpG-transcript pairs suggests that DNA methylation regulates nearby rather than remote gene expression. The putatively causal roles of methylation and expression of CHRNA5 in relation to COPD and lung cancer provide evidence for a mechanistic link between patterns of smoking-related epigenetic variation and lung diseases, and highlight potential therapeutic targets for lung diseases and smoking cessation.

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Cell–cell coupling and DNA methylation abnormal phenotypes in the after-hours mice

Epigenetics & Chromatin ◽

10.1186/s13072-020-00373-5 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Federico Tinarelli ◽

Elena Ivanova ◽

Ilaria Colombi ◽

Erica Barini ◽

Edoardo Balzani ◽

...

Keyword(s):

Gene Expression ◽

Dna Methylation ◽

Neuronal Networks ◽

Molecular Mechanisms ◽

Ex Vivo ◽

Neuronal Cultures ◽

Functional Impairments ◽

After Hours ◽

The Impact

Abstract Background DNA methylation has emerged as an important epigenetic regulator of brain processes, including circadian rhythms. However, how DNA methylation intervenes between environmental signals, such as light entrainment, and the transcriptional and translational molecular mechanisms of the cellular clock is currently unknown. Here, we studied the after-hours mice, which have a point mutation in the Fbxl3 gene and a lengthened circadian period. Methods In this study, we used a combination of in vivo, ex vivo and in vitro approaches. We measured retinal responses in Afh animals and we have run reduced representation bisulphite sequencing (RRBS), pyrosequencing and gene expression analysis in a variety of brain tissues ex vivo. In vitro, we used primary neuronal cultures combined to micro electrode array (MEA) technology and gene expression. Results We observed functional impairments in mutant neuronal networks, and a reduction in the retinal responses to light-dependent stimuli. We detected abnormalities in the expression of photoreceptive melanopsin (OPN4). Furthermore, we identified alterations in the DNA methylation pathways throughout the retinohypothalamic tract terminals and links between the transcription factor Rev-Erbα and Fbxl3. Conclusions The results of this study, primarily represent a contribution towards an understanding of electrophysiological and molecular phenotypic responses to external stimuli in the Afh model. Moreover, as DNA methylation has recently emerged as a new regulator of neuronal networks with important consequences for circadian behaviour, we discuss the impact of the Afh mutation on the epigenetic landscape of circadian biology.

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PITX2 DNA-Methylation: Predictive versus Prognostic Value for Anthracycline-Based Chemotherapy in Triple-Negative Breast Cancer Patients

Breast Care ◽

10.1159/000510468 ◽

2020 ◽

pp. 1-9

Author(s):

Rudolf Napieralski ◽

Gabriele Schricker ◽

Gert Auer ◽

Michaela Aubele ◽

Jonathan Perkins ◽

...

Keyword(s):

Breast Cancer ◽

Dna Methylation ◽

Cancer Patients ◽

Triple Negative Breast Cancer ◽

Predictive Value ◽

Untreated Patient ◽

Triple Negative ◽

Statistical Significance ◽

Breast Cancer Patients ◽

The Impact

Background: PITX2 DNA methylation has been shown to predict outcomes in high-risk breast cancer patients after anthracycline-based chemotherapy. To determine its prognostic versus predictive value, the impact of PITX2 DNA methylation on outcomes was studied in an untreated cohort vs. an anthracycline-treated triple-negative breast cancer (TNBC) cohort. Material and Methods: The percent DNA methylation ratio (PMR) of paired-like homeodomain transcription factor 2 (PITX2) was determined by a validated methylation-specific real-time PCR test. Patient samples of routinely collected archived formalin-fixed paraffin-embedded (FFPE) tissue and clinical data from 144 TNBC patients of 2 independent cohorts (i.e., 66 untreated patients and 78 patients treated with anthracycline-based chemotherapy) were analyzed. Results: The risk of 5- and 10-year overall survival (OS) increased continuously with rising PITX2 DNA methylation in the anthracycline-treated population, but it increased only slightly during 10-year follow-up time in the untreated patient population. PITX2 DNA methylation with a PMR cutoff of 2 did not show significance for poor vs. good outcomes (OS) in the untreated patient cohort (HR = 1.55; p = 0.259). In contrast, the PITX2 PMR cutoff of 2 identified patients with poor (PMR >2) vs. good (PMR ≤2) outcomes (OS) with statistical significance in the anthracycline-treated cohort (HR = 3.96; p = 0.011). The results in the subgroup of patients who did receive anthracyclines only (no taxanes) confirmed this finding (HR = 5.71; p = 0.014). Conclusion: In this hypothesis-generating study PITX2 DNA methylation demonstrated predominantly predictive value in anthracycline treatment in TNBC patients. The risk of poor outcome (OS) correlates with increasing PITX2 DNA methylation.

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