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Yan X, Fang Y, Yuan Y, Ding Y, Yu H, Li Y, Shi Q, Gao Y, Zhou X, Zhang D, Yuan E, Zhou H, Zhao X, Zhang L. Combined analysis of the effects of hypoxia and oxidative stress on DNA methylation and the transcriptome in HTR-8/SVneo trophoblast cells. J Cell Mol Med 2024; 28:e18469. [PMID: 38899809 PMCID: PMC11187809 DOI: 10.1111/jcmm.18469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 05/08/2024] [Accepted: 05/22/2024] [Indexed: 06/21/2024] Open
Abstract
The alterations in DNA methylation and transcriptome in trophoblast cells under conditions of low oxygen and oxidative stress have major implications for pregnancy-related disorders. However, the exact mechanism is still not fully understood. In this study, we established models of hypoxia (H group) and oxidative stress (HR group) using HTR-8/SVneo trophoblast cells and performed combined analysis of genome-wide DNA methylation changes using reduced representation bisulphite sequencing and transcriptome expression changes using RNA sequencing. Our findings revealed that the H group exhibited a higher number of differentially methylated genes and differentially expressed genes than the HR group. In the H group, only 0.90% of all differentially expressed genes displayed simultaneous changes in DNA methylation and transcriptome expression. After the threshold was expanded, this number increased to 6.29% in the HR group. Notably, both the H group and HR group exhibited concurrent alterations in DNA methylation and transcriptome expression within Axon guidance and MAPK signalling pathway. Among the top 25 differentially methylated KEGG pathways in the promoter region, 11 pathways were commonly enriched in H group and HR group, accounting for 44.00%. Among the top 25 KEGG pathways in transcriptome with significant differences between the H group and HR group, 10 pathways were consistent, accounting for 40.00%. By integrating our previous data on DNA methylation from preeclamptic placental tissues, we identified that the ANKRD37 and PFKFB3 genes may contribute to the pathogenesis of preeclampsia through DNA methylation-mediated transcriptome expression under hypoxic conditions.
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Affiliation(s)
- Xinjing Yan
- Department of Laboratory MedicineThird Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
- Zhengzhou Key Laboratory for In Vitro Diagnosis of Hypertensive Disorders of PregnancyZhengzhouChina
| | - Yang Fang
- Department of Laboratory MedicineThird Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
- Zhengzhou Key Laboratory for In Vitro Diagnosis of Hypertensive Disorders of PregnancyZhengzhouChina
| | - Yujie Yuan
- Judicial Appraisal InstitutionThird Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Yangnan Ding
- Department of Laboratory MedicineThird Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
- Zhengzhou Key Laboratory for In Vitro Diagnosis of Hypertensive Disorders of PregnancyZhengzhouChina
| | - Haiyang Yu
- Department of Laboratory MedicineThird Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
- Zhengzhou Key Laboratory for In Vitro Diagnosis of Hypertensive Disorders of PregnancyZhengzhouChina
| | - Yina Li
- Department of Laboratory MedicineThird Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
- Zhengzhou Key Laboratory for In Vitro Diagnosis of Hypertensive Disorders of PregnancyZhengzhouChina
| | - Qianqian Shi
- Department of Laboratory MedicineThird Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
- Zhengzhou Key Laboratory for In Vitro Diagnosis of Hypertensive Disorders of PregnancyZhengzhouChina
| | - Yongrui Gao
- Department of Laboratory MedicineThird Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
- Zhengzhou Key Laboratory for In Vitro Diagnosis of Hypertensive Disorders of PregnancyZhengzhouChina
| | - Xinyuan Zhou
- Department of Obstetrics and GynecologyThe Third Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Dongxin Zhang
- Microbiome Medicine Center, Department of Laboratory MedicineZhujiang Hospital, Southern Medical UniversityGuangzhouChina
| | - Enwu Yuan
- Department of Laboratory MedicineThird Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
- Zhengzhou Key Laboratory for In Vitro Diagnosis of Hypertensive Disorders of PregnancyZhengzhouChina
- Tianjian Advanced Biomedical LaboratoryZhengzhouChina
| | - Hongwei Zhou
- Microbiome Medicine Center, Department of Laboratory MedicineZhujiang Hospital, Southern Medical UniversityGuangzhouChina
| | - Xin Zhao
- Tianjian Advanced Biomedical LaboratoryZhengzhouChina
| | - Linlin Zhang
- Department of Laboratory MedicineThird Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
- Zhengzhou Key Laboratory for In Vitro Diagnosis of Hypertensive Disorders of PregnancyZhengzhouChina
- Tianjian Advanced Biomedical LaboratoryZhengzhouChina
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2
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Keighley LM, Lynch-Sutherland CF, Almomani SN, Eccles MR, Macaulay EC. Unveiling the hidden players: The crucial role of transposable elements in the placenta and their potential contribution to pre-eclampsia. Placenta 2023; 141:57-64. [PMID: 37301654 DOI: 10.1016/j.placenta.2023.05.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 05/21/2023] [Accepted: 05/26/2023] [Indexed: 06/12/2023]
Abstract
The human placenta is a vital connection between maternal and fetal tissues, allowing for the exchange of molecules and modulation of immune interactions during pregnancy. Interestingly, some of the placenta's unique functions can be attributed to transposable elements (TEs), which are DNA sequences that have mobilised into the genome. Co-option throughout mammalian evolution has led to the generation of TE-derived regulators and TE-derived genes, some of which are expressed in the placenta but silenced in somatic tissues. TE genes encompass both TE-derived genes with a repeat element in the coding region and TE-derived regulatory regions such as alternative promoters and enhancers. Placental-specific TE genes are known to contribute to the placenta's unique functions, and interestingly, they are also expressed in some cancers and share similar functions. There is evidence to support that aberrant activity of TE genes may contribute to placental pathologies, cancer and autoimmunity. In this review, we highlight the crucial roles of TE genes in placental function, and how their dysregulation may lead to pre-eclampsia, a common and dangerous placental condition. We provide a summary of the functional TE genes in the placenta to offer insight into their significance in normal and abnormal human development. Ultimately, this review highlights an opportunity for future research to investigate the potential dysregulation of TE genes in the development of placental pathologies such as pre-eclampsia. Further understanding of TE genes and their role in the placenta could lead to significant improvements in maternal and fetal health.
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Affiliation(s)
- Laura M Keighley
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, 9054, New Zealand
| | - Chiemi F Lynch-Sutherland
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, 9054, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, Level 2, 3A Symonds Street, Auckland, New Zealand
| | - Suzan N Almomani
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, 9054, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, Level 2, 3A Symonds Street, Auckland, New Zealand
| | - Michael R Eccles
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, 9054, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, Level 2, 3A Symonds Street, Auckland, New Zealand
| | - Erin C Macaulay
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, 9054, New Zealand.
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3
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Demeneva VV, Tolmacheva EN, Nikitina TV, Sazhenova EA, Yuriev SY, Makhmutkhodzhaev AS, Zuev AS, Filatova SA, Dmitriev AE, Darkova YA, Nazarenko LP, Lebedev IN, Vasilyev SA. Expression of the NUP153 and YWHAB genes from their canonical promoters and alternative promoters of the LINE-1 retrotransposon in the placenta of the first trimester of pregnancy. Vavilovskii Zhurnal Genet Selektsii 2023; 27:63-71. [PMID: 36923475 PMCID: PMC10009475 DOI: 10.18699/vjgb-23-09] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 12/26/2022] [Accepted: 12/30/2022] [Indexed: 03/11/2023] Open
Abstract
The placenta has a unique hypomethylated genome. Due to this feature of the placenta, there is a potential possibility of using regulatory elements derived from retroviruses and retrotransposons, which are suppressed by DNA methylation in the adult body. In addition, there is an abnormal increase in the level of methylation of the LINE-1 retrotransposon in the chorionic trophoblast in spontaneous abortions with both normal karyotype and aneuploidy on different chromosomes, which may be associated with impaired gene transcription using LINE-1 regulatory elements. To date, 988 genes that can be expressed from alternative LINE-1 promoters have been identified. Using the STRING tool, genes (NUP153 and YWHAB) were selected, the products of which have significant functional relationships with proteins highly expressed in the placenta and involved in trophoblast differentiation. This study aimed to analyze the expression of the NUP153 and YWHAB genes, highly active in the placenta, from canonical and alternative LINE-1 promoters in the germinal part of the placenta of spontaneous and induced abortions. Gene expression analysis was performed using real-time PCR in chorionic villi and extraembryonic mesoderm of induced abortions (n = 10), adult lymphocytes (n = 10), spontaneous abortions with normal karyotype (n = 10), and with the most frequent aneuploidies in the first trimester of pregnancy (trisomy 16 (n = 8) and monosomy X (n = 6)). The LINE-1 methylation index was assessed in the chorionic villi of spontaneous abortions using targeted bisulfite massive parallel sequencing. The level of expression of both genes from canonical promoters was higher in blood lymphocytes than in placental tissues (p < 0.05). However, the expression level of the NUP153 gene from the alternative LINE-1 promoter was 17 times higher in chorionic villi and 23 times higher in extraembryonic mesoderm than in lymphocytes (p < 0.05). The expression level of NUP153 and YWHAB from canonical promoters was higher in the group of spontaneous abortions with monosomy X compared to all other groups (p <0.05). The LINE-1 methylation index negatively correlated with the level of gene expression from both canonical (NUP153 - R = -0.59, YWHAB - R = -0.52, p < 0.05) and alternative LINE-1 promoters (NUP153 - R = -0.46, YWHAB - R = -0.66, p < 0.05). Thus, the observed increase in the LINE-1 methylation index in the placenta of spontaneous abortions is associated with the level of expression of the NUP153 and YWHAB genes not only from alternative but also from canonical promoters, which can subsequently lead to negative consequences for normal embryogenesis.
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Affiliation(s)
- V V Demeneva
- Research Institute of Medical Genetics, Tomsk National Research Medical Center of the Russian Academy of Sciences, Tomsk, Russia
| | - E N Tolmacheva
- Research Institute of Medical Genetics, Tomsk National Research Medical Center of the Russian Academy of Sciences, Tomsk, Russia
| | - T V Nikitina
- Research Institute of Medical Genetics, Tomsk National Research Medical Center of the Russian Academy of Sciences, Tomsk, Russia
| | - E A Sazhenova
- Research Institute of Medical Genetics, Tomsk National Research Medical Center of the Russian Academy of Sciences, Tomsk, Russia
| | - S Yu Yuriev
- Siberian State Medical University, Tomsk, Russia
| | | | - A S Zuev
- Research Institute of Medical Genetics, Tomsk National Research Medical Center of the Russian Academy of Sciences, Tomsk, Russia
| | - S A Filatova
- National Research Tomsk State University, Tomsk, Russia
| | - A E Dmitriev
- National Research Tomsk State University, Tomsk, Russia
| | - Ya A Darkova
- National Research Tomsk State University, Tomsk, Russia
| | - L P Nazarenko
- Research Institute of Medical Genetics, Tomsk National Research Medical Center of the Russian Academy of Sciences, Tomsk, Russia
| | - I N Lebedev
- Research Institute of Medical Genetics, Tomsk National Research Medical Center of the Russian Academy of Sciences, Tomsk, Russia Siberian State Medical University, Tomsk, Russia
| | - S A Vasilyev
- Research Institute of Medical Genetics, Tomsk National Research Medical Center of the Russian Academy of Sciences, Tomsk, Russia National Research Tomsk State University, Tomsk, Russia
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Weyde KVF, Olsen AK, Duale N, Kamstra JH, Skogheim TS, Caspersen IH, Engel SM, Biele G, Xia Y, Meltzer HM, Aase H, Villanger GD. Gestational blood levels of toxic metal and essential element mixtures and associations with global DNA methylation in pregnant women and their infants. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 787:147621. [PMID: 34000534 DOI: 10.1016/j.scitotenv.2021.147621] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 03/24/2021] [Accepted: 05/03/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Pregnant women and their fetuses are exposed to multiple toxic metals that together with variations in essential element levels may alter epigenetic regulation, such as DNA methylation. OBJECTIVES The aim of the study was to investigate the associations between gestational levels of toxic metals and essential elements and mixtures thereof, with global DNA methylation levels in pregnant women and their newborn children. METHODS Using 631 mother-child pairs from a prospective birth cohort (The Norwegian Mother, Father and Child Cohort Study), we measured maternal blood concentration (gestation week ~18) of five toxic metals and seven essential elements. We investigated associations as individual exposures and two-way interactions, using elastic net regression, and total mixture, using quantile g-computation, with blood levels of 5-methylcytocine (5mC) and 5-hydroxymethylcytosine (5hmC) in mothers during pregnancy and their newborn children (cord blood). Multiple testing was adjusted for using the Benjamini and Hochberg false discovery rate (FDR) approach. RESULTS The most sensitive marker of DNA methylation appeared to be 5mC levels. In pregnant mothers, elastic net regression indicated associations between 5mC and selenium and lead (non-linear), while in newborns results indicated relationships between maternal selenium, cobalt (non-linear) and mercury and 5mC, as well as copper (non-linear) and 5hmC levels. Several possible two-way interactions were identified (e.g. arsenic and mercury, and selenium and maternal smoking in newborns). None of these findings met the FDR threshold for multiple testing. No net effect was observed in the joint (mixture) exposure-approach using quantile g-computation. CONCLUSION We identified few associations between gestational levels of several toxic metals and essential elements and global DNA methylation in pregnant mothers and their newborn children. As DNA methylation dysregulation might be a key mechanism in disease development and thus of high importance for public health, our results should be considered as important candidates to investigate in future studies.
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Affiliation(s)
| | | | - Nur Duale
- Norwegian Institute of Public Health, Oslo, Norway
| | - Jorke H Kamstra
- Institute for Risk Assessment Sciences, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, the Netherlands
| | | | | | - Stephanie M Engel
- Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, USA
| | - Guido Biele
- Norwegian Institute of Public Health, Oslo, Norway; Department of Psychology, University of Oslo, Oslo, Norway
| | - Yankai Xia
- State Key Laboratory of Reproductive Medicine, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, China; Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing, China
| | | | - Heidi Aase
- Norwegian Institute of Public Health, Oslo, Norway
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5
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Sakamoto Y, Zaha S, Suzuki Y, Seki M, Suzuki A. Application of long-read sequencing to the detection of structural variants in human cancer genomes. Comput Struct Biotechnol J 2021; 19:4207-4216. [PMID: 34527193 PMCID: PMC8350331 DOI: 10.1016/j.csbj.2021.07.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 07/20/2021] [Accepted: 07/25/2021] [Indexed: 01/02/2023] Open
Abstract
In recent years, the so-called long-read sequencing technology has had a substantial impact on various aspects of genome sciences. Here, we introduce recent studies of cancerous structural variants (SVs) using long-read sequencing technologies, namely Pacific Biosciences (PacBio) sequencers, Oxford Nanopore Technologies (ONT) sequencers, and linked-read methods. By taking advantage of long-read lengths, these technologies have enabled the precise detection of SVs, including long insertions by transposable elements, such as LINE-1. In addition to SV detection, the epigenome status (including DNA methylation and haplotype information) surrounding SV loci has also been unveiled by long-read sequencing technologies, to identify the effects of SVs. Among the various research fields in which long-read sequencing has been applied, cancer genomics has shown the most remarkable advances. In fact, many studies are beginning to shed light on the detection of SVs and the elucidation of their complex structures in various types of cancer. In the particular case of cancers, we summarize the technical limitations of the application of this technology to the analysis of clinical samples. We will introduce recent achievements from this viewpoint. However, a similar approach will be started for other applications in the near future. Therefore, by complementing the current short-read sequencing analysis, long-read sequencing should reveal the complex nature of human genomes in their healthy and disease states, which will open a new opportunity for a better understanding of disease development and for a novel strategy for drug development.
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Affiliation(s)
- Yoshitaka Sakamoto
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
| | - Suzuko Zaha
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
| | - Yutaka Suzuki
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
| | - Masahide Seki
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
| | - Ayako Suzuki
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
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6
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Martinez VD, Sage AP, Minatel BC, Marshall EA, Price EM, Becker-Santos DD, Robinson WP, Lam WL. Human placental piwi-interacting RNA transcriptome is characterized by expression from the DLK1-DIO3 imprinted region. Sci Rep 2021; 11:14981. [PMID: 34294738 PMCID: PMC8298716 DOI: 10.1038/s41598-021-93885-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 06/17/2021] [Indexed: 01/07/2023] Open
Abstract
The placenta is vital to embryonic development and requires a finely-tuned pattern of gene expression, achieved in part by its unique epigenetic landscape. Piwi-interacting RNAs (piRNAs) are a class of small-non-coding RNA with established roles as epigenetic regulators of gene expression, largely via methylation of targeted DNA sequences. The expression of piRNAs have mainly been described in germ cells, but a fraction have been shown to retain expression in adult somatic tissues. To aid in understanding the contribution of these regulators in the placenta, we provide the first description of the piRNA transcriptome in human placentas. We find 297 piRNAs to be preferentially expressed in the human placenta, a subset of which are expressed at higher levels relative to testes samples. We also observed a large proportion of placental piRNAs to be expressed from a single locus, as distinct from canonical cluster locations associated with transposable element silencing. Finally, we find that 15 of the highest-expressed placental piRNAs maps to the DLK1-DIO3 locus, suggesting a link to placental biology. Our findings suggest that piRNAs could contribute to the molecular networks defining placental function in humans, and a biological impact of piRNA expression beyond germ cells.
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Affiliation(s)
- Victor D Martinez
- British Columbia Cancer Research Centre, 675 West 10th Ave, Vancouver, BC, Canada. .,IWK Health Centre, Halifax, NS, Canada. .,Department of Pathology, Faculty of Medicine, Dalhousie University, 5850/5980 University Avenue, Halifax, NS, B3K 6R8, Canada.
| | - Adam P Sage
- British Columbia Cancer Research Centre, 675 West 10th Ave, Vancouver, BC, Canada
| | - Brenda C Minatel
- British Columbia Cancer Research Centre, 675 West 10th Ave, Vancouver, BC, Canada
| | - Erin A Marshall
- British Columbia Cancer Research Centre, 675 West 10th Ave, Vancouver, BC, Canada
| | - E Magda Price
- BC Children's Hospital Research Institute, Vancouver, BC, Canada.,Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | | | - Wendy P Robinson
- BC Children's Hospital Research Institute, Vancouver, BC, Canada.,Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Wan L Lam
- British Columbia Cancer Research Centre, 675 West 10th Ave, Vancouver, BC, Canada
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7
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Inkster AM, Yuan V, Konwar C, Matthews AM, Brown CJ, Robinson WP. A cross-cohort analysis of autosomal DNA methylation sex differences in the term placenta. Biol Sex Differ 2021; 12:38. [PMID: 34044884 PMCID: PMC8162041 DOI: 10.1186/s13293-021-00381-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 05/17/2021] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Human placental DNA methylation (DNAme) data is a valuable resource for studying sex differences during gestation, as DNAme profiles after delivery reflect the cumulative effects of gene expression patterns and exposures across gestation. Here, we present an analysis of sex differences in autosomal DNAme in the uncomplicated term placenta (n = 343) using the Illumina 450K array. RESULTS At a false discovery rate < 0.05 and a mean sex difference in DNAme beta value of > 0.10, we identified 162 autosomal CpG sites that were differentially methylated by sex and replicated in an independent cohort of samples (n = 293). Several of these differentially methylated CpG sites were part of larger correlated regions of sex differential DNAme. Although global DNAme levels did not differ by sex, the majority of significantly differentially methylated CpGs were more highly methylated in male placentae, the opposite of what is seen in differential methylation analyses of somatic tissues. Patterns of autosomal DNAme at these 162 CpGs were significantly associated with maternal age (in males) and newborn birthweight standard deviation (in females). CONCLUSIONS Our results provide a comprehensive analysis of sex differences in autosomal DNAme in the term human placenta. We report a list of high-confidence autosomal sex-associated differentially methylated CpGs and identify several key features of these loci that suggest their relevance to sex differences observed in normative and complicated pregnancies.
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Affiliation(s)
- Amy M. Inkster
- BC Children’s Hospital Research Institute, 950 W 28th Ave, Vancouver, V6H 3N1 Canada
- Department of Medical Genetics, University of British Columbia, 4500 Oak St, Vancouver, V6H 3N1 Canada
| | - Victor Yuan
- BC Children’s Hospital Research Institute, 950 W 28th Ave, Vancouver, V6H 3N1 Canada
- Department of Medical Genetics, University of British Columbia, 4500 Oak St, Vancouver, V6H 3N1 Canada
| | - Chaini Konwar
- BC Children’s Hospital Research Institute, 950 W 28th Ave, Vancouver, V6H 3N1 Canada
- Centre for Molecular Medicine and Therapeutics, 950 W 28th Ave, Vancouver, V6H 3N1 Canada
| | - Allison M. Matthews
- BC Children’s Hospital Research Institute, 950 W 28th Ave, Vancouver, V6H 3N1 Canada
- Department of Medical Genetics, University of British Columbia, 4500 Oak St, Vancouver, V6H 3N1 Canada
- Centre for Molecular Medicine and Therapeutics, 950 W 28th Ave, Vancouver, V6H 3N1 Canada
- Department of Pathology & Laboratory Medicine, University of British Columbia, 2211 Wesbrook Mall, Vancouver, V6T 1Z7 Canada
| | - Carolyn J. Brown
- Department of Medical Genetics, University of British Columbia, 4500 Oak St, Vancouver, V6H 3N1 Canada
| | - Wendy P. Robinson
- BC Children’s Hospital Research Institute, 950 W 28th Ave, Vancouver, V6H 3N1 Canada
- Department of Medical Genetics, University of British Columbia, 4500 Oak St, Vancouver, V6H 3N1 Canada
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8
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Extensive Placental Methylation Profiling in Normal Pregnancies. Int J Mol Sci 2021; 22:ijms22042136. [PMID: 33669975 PMCID: PMC7924820 DOI: 10.3390/ijms22042136] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/17/2021] [Accepted: 02/18/2021] [Indexed: 02/07/2023] Open
Abstract
The placental methylation pattern is crucial for the regulation of genes involved in trophoblast invasion and placental development, both key events for fetal growth. We investigated LINE-1 methylation and methylome profiling using a methylation EPIC array and the targeted methylation sequencing of 154 normal, full-term pregnancies, stratified by birth weight percentiles. LINE-1 methylation showed evidence of a more pronounced hypomethylation in small neonates compared with normal and large for gestational age. Genome-wide methylation, performed in two subsets of pregnancies, showed very similar methylation profiles among cord blood samples while placentae from different pregnancies appeared very variable. A unique methylation profile emerged in each placenta, which could represent the sum of adjustments that the placenta made during the pregnancy to preserve the epigenetic homeostasis of the fetus. Investigations into the 1000 most variable sites between cord blood and the placenta showed that promoters and gene bodies that are hypermethylated in the placenta are associated with blood-specific functions, whereas those that are hypomethylated belong mainly to pathways involved in cancer. These features support the functional analogies between a placenta and cancer. Our results, which provide a comprehensive analysis of DNA methylation profiling in the human placenta, suggest that its peculiar dynamicity can be relevant for understanding placental plasticity in response to the environment.
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9
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Yuan V, Hui D, Yin Y, Peñaherrera MS, Beristain AG, Robinson WP. Cell-specific characterization of the placental methylome. BMC Genomics 2021; 22:6. [PMID: 33407091 PMCID: PMC7788826 DOI: 10.1186/s12864-020-07186-6] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 10/26/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND DNA methylation (DNAm) profiling has emerged as a powerful tool for characterizing the placental methylome. However, previous studies have focused primarily on whole placental tissue, which is a mixture of epigenetically distinct cell populations. Here, we present the first methylome-wide analysis of first trimester (n = 9) and term (n = 19) human placental samples of four cell populations: trophoblasts, Hofbauer cells, endothelial cells, and stromal cells, using the Illumina EPIC methylation array, which quantifies DNAm at > 850,000 CpGs. RESULTS The most distinct DNAm profiles were those of placental trophoblasts, which are central to many pregnancy-essential functions, and Hofbauer cells, which are a rare fetal-derived macrophage population. Cell-specific DNAm occurs at functionally-relevant genes, including genes associated with placental development and preeclampsia. Known placental-specific methylation marks, such as those associated with genomic imprinting, repetitive element hypomethylation, and placental partially methylated domains, were found to be more pronounced in trophoblasts and often absent in Hofbauer cells. Lastly, we characterize the cell composition and cell-specific DNAm dynamics across gestation. CONCLUSIONS Our results provide a comprehensive analysis of DNAm in human placental cell types from first trimester and term pregnancies. This data will serve as a useful DNAm reference for future placental studies, and we provide access to this data via download from GEO (GSE159526), through interactive exploration from the web browser ( https://robinsonlab.shinyapps.io/Placental_Methylome_Browser/ ), and through the R package planet, which allows estimation of cell composition directly from placental DNAm data.
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Affiliation(s)
- Victor Yuan
- BC Children’s Hospital Research Institute, Vancouver, BC Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, BC Canada
| | - Desmond Hui
- BC Children’s Hospital Research Institute, Vancouver, BC Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, BC Canada
| | - Yifan Yin
- BC Children’s Hospital Research Institute, Vancouver, BC Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, BC Canada
| | - Maria S. Peñaherrera
- BC Children’s Hospital Research Institute, Vancouver, BC Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, BC Canada
| | - Alexander G. Beristain
- BC Children’s Hospital Research Institute, Vancouver, BC Canada
- Department of Obstetrics and Gynaecology, University of British Columbia, Vancouver, BC Canada
| | - Wendy P. Robinson
- BC Children’s Hospital Research Institute, Vancouver, BC Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, BC Canada
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10
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Vasilyev SA, Tolmacheva EN, Vasilyeva OY, Markov AV, Zhigalina DI, Zatula LA, Lee VA, Serdyukova ES, Sazhenova EA, Nikitina TV, Kashevarova AA, Lebedev IN. LINE-1 retrotransposon methylation in chorionic villi of first trimester miscarriages with aneuploidy. J Assist Reprod Genet 2021; 38:139-149. [PMID: 33170392 PMCID: PMC7823001 DOI: 10.1007/s10815-020-02003-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Accepted: 11/02/2020] [Indexed: 01/15/2023] Open
Abstract
PURPOSE High frequency of aneuploidy in meiosis and cleavage stage coincides with waves of epigenetic genome reprogramming that may indicate a possible association between epigenetic mechanisms and aneuploidy occurrence. This study aimed to assess the methylation level of the long interspersed repeat element 1 (LINE-1) retrotransposon in chorionic villi of first trimester miscarriages with a normal karyotype and aneuploidy. METHODS The methylation level was assessed at 19 LINE-1 promoter CpG sites in chorionic villi of 141 miscarriages with trisomy of chromosomes 2, 6, 8-10, 13-15, 16, 18, 20-22, and monosomy X using massive parallel sequencing. RESULTS The LINE-1 methylation level was elevated statistically significant in chorionic villi of miscarriages with both trisomy (45.2 ± 4.3%) and monosomy X (46.9 ± 4.2%) compared with that in induced abortions (40.0 ± 2.4%) (p < 0.00001). The LINE-1 methylation levels were specific for miscarriages with different aneuploidies and significantly increased in miscarriages with trisomies 8, 14, and 18 and monosomy X (p < 0.05). The LINE-1 methylation level increased with gestational age both for group of miscarriages regardless of karyotype (R = 0.21, p = 0.012) and specifically for miscarriages with trisomy 16 (R = 0.48, p = 0.007). LINE-1 methylation decreased with maternal age in miscarriages with a normal karyotype (R = - 0.31, p = 0.029) and with trisomy 21 (R = - 0.64, p = 0.024) and increased with paternal age for miscarriages with trisomy 16 (R = 0.38, p = 0.048) and monosomy X (R = 0.73, p = 0.003). CONCLUSION Our results indicate that the pathogenic effects of aneuploidy in human embryogenesis can be supplemented with significant epigenetic changes in the repetitive sequences.
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Affiliation(s)
- Stanislav A Vasilyev
- Research Institute of Medical Genetics, Tomsk National Research Medical Center, Nab. R. Ushaiki, 10, Tomsk, Russia.
- Biological Institute, National Research Tomsk State University, Lenina, 36, Tomsk, Russia.
| | - Ekaterina N Tolmacheva
- Research Institute of Medical Genetics, Tomsk National Research Medical Center, Nab. R. Ushaiki, 10, Tomsk, Russia
| | - Oksana Yu Vasilyeva
- Research Institute of Medical Genetics, Tomsk National Research Medical Center, Nab. R. Ushaiki, 10, Tomsk, Russia
| | - Anton V Markov
- Research Institute of Medical Genetics, Tomsk National Research Medical Center, Nab. R. Ushaiki, 10, Tomsk, Russia
| | - Daria I Zhigalina
- Research Institute of Medical Genetics, Tomsk National Research Medical Center, Nab. R. Ushaiki, 10, Tomsk, Russia
| | - Lada A Zatula
- Department of Medical Genetics, Siberian State Medical University, Moskovskiy Trakt, 2, Tomsk, Russia
| | - Vasilissa A Lee
- Department of Medical Genetics, Siberian State Medical University, Moskovskiy Trakt, 2, Tomsk, Russia
| | - Ekaterina S Serdyukova
- Biological Institute, National Research Tomsk State University, Lenina, 36, Tomsk, Russia
| | - Elena A Sazhenova
- Research Institute of Medical Genetics, Tomsk National Research Medical Center, Nab. R. Ushaiki, 10, Tomsk, Russia
| | - Tatyana V Nikitina
- Research Institute of Medical Genetics, Tomsk National Research Medical Center, Nab. R. Ushaiki, 10, Tomsk, Russia
| | - Anna A Kashevarova
- Research Institute of Medical Genetics, Tomsk National Research Medical Center, Nab. R. Ushaiki, 10, Tomsk, Russia
| | - Igor N Lebedev
- Research Institute of Medical Genetics, Tomsk National Research Medical Center, Nab. R. Ushaiki, 10, Tomsk, Russia
- Department of Medical Genetics, Siberian State Medical University, Moskovskiy Trakt, 2, Tomsk, Russia
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11
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Barrow TM, Wong Doo N, Milne RL, Giles GG, Willmore E, Strathdee G, Byun HM. Analysis of retrotransposon subfamily DNA methylation reveals novel early epigenetic changes in chronic lymphocytic leukemia. Haematologica 2021; 106:98-110. [PMID: 31919093 PMCID: PMC7776340 DOI: 10.3324/haematol.2019.228478] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 01/07/2020] [Indexed: 11/30/2022] Open
Abstract
Retrotransposons such as LINE-1 and Alu comprise >25% of the human genome. While global hypomethylation of these elements has been widely reported in solid tumours, their epigenetic dysregulation is yet to be characterised in chronic lymphocytic leukemia (CLL), and there has been scant consideration of their evolutionary history that mediates sensitivity to hypomethylation. Here, we developed an approach for locus- and evolutionary subfamily-specific analysis of retrotransposons using the Illumina Infinium Human Methylation 450K microarray platform, which we applied to publicly-available datasets from CLL and other haematological malignancies. We identified 9,797 microarray probes mapping to 117 LINE-1 subfamilies and 13,130 mapping to 37 Alu subfamilies. Of these, 10,782 were differentially methylated (PFDR<0.05) in CLL patients (n=139) compared with healthy individuals (n=14), with enrichment at enhancers (P=0.002). Differential methylation was associated with evolutionary age of LINE-1 (r2=0.31, P=0.003) and Alu (r2=0.74, P=0.002) elements, with greater hypomethylation of older subfamilies (L1M, AluJ). Locus-specific hypomethylation was associated with differential expression of proximal genes, including DCLK2, HK1, ILRUN, TANK, TBCD, TNFRSF1B and TXNRD2, with higher expression of DCLK2 and TNFRSF1B associated with reduced patient survival. Hypomethylation at nine loci was highly frequent in CLL (>90% patients) but not observed in healthy individuals or other leukaemias, and was detectable in blood samples taken prior to CLL diagnosis in 9 of 82 individuals from the Melbourne Collaborative Cohort Study. Our results demonstrate differential methylation of retrotransposons in CLL by their evolutionary heritage that modulates expression of proximal genes.
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Affiliation(s)
- Timothy M Barrow
- Faculty of Health Sciences and Wellbeing, University of Sunderland, Sunderland, United Kingdom
| | - Nicole Wong Doo
- Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, Australia
| | - Roger L Milne
- Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, Australia
| | - Graham G Giles
- Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, Australia
| | - Elaine Willmore
- Northern Institute for Cancer Research, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Gordon Strathdee
- Northern Institute for Cancer Research, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Hyang-Min Byun
- Population Health Sciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
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12
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Rousseaux S, Seyve E, Chuffart F, Bourova-Flin E, Benmerad M, Charles MA, Forhan A, Heude B, Siroux V, Slama R, Tost J, Vaiman D, Khochbin S, Lepeule J. Immediate and durable effects of maternal tobacco consumption alter placental DNA methylation in enhancer and imprinted gene-containing regions. BMC Med 2020; 18:306. [PMID: 33023569 PMCID: PMC7542140 DOI: 10.1186/s12916-020-01736-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 08/06/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Although exposure to cigarette smoking during pregnancy has been associated with alterations of DNA methylation in the cord blood or placental cells, whether such exposure before pregnancy could induce epigenetic alterations in the placenta of former smokers has never been investigated. METHODS Our approach combined the analysis of placenta epigenomic (ENCODE) data with newly generated DNA methylation data obtained from 568 pregnant women, the largest cohort to date, either actively smoking during their pregnancy or formerly exposed to tobacco smoking. RESULTS This strategy resulted in several major findings. First, among the 203 differentially methylated regions (DMRs) identified by the epigenome-wide association study, 152 showed "reversible" alterations of DNA methylation, only present in the placenta of current smokers, whereas 26 were also found altered in former smokers, whose placenta had not been exposed directly to cigarette smoking. Although the absolute methylation changes were smaller than those observed in other contexts, such as in some congenital diseases, the observed alterations were consistent within each DMR. This observation was further supported by a demethylation of LINE-1 sequences in the placentas of both current (beta-coefficient (β) (95% confidence interval (CI)), - 0.004 (- 0.008; 0.001)) and former smokers (β (95% CI), - 0.006 (- 0.011; - 0.001)) compared to nonsmokers. Second, the 203 DMRs were enriched in epigenetic marks corresponding to enhancer regions, including monomethylation of lysine 4 and acetylation of lysine 27 of histone H3 (respectively H3K4me1 and H3K27ac). Third, smoking-associated DMRs were also found near and/or overlapping 10 imprinted genes containing regions (corresponding to 16 genes), notably including the NNAT, SGCE/PEG10, and H19/MIR675 loci. CONCLUSIONS Our results pointing towards genomic regions containing the imprinted genes as well as enhancers as preferential targets suggest mechanisms by which tobacco could directly impact the fetus and future child. The persistence of significant DNA methylation changes in the placenta of former smokers supports the hypothesis of an "epigenetic memory" of exposure to cigarette smoking before pregnancy. This observation not only is conceptually revolutionary, but these results also bring crucial information in terms of public health concerning potential long-term detrimental effects of smoking in women.
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Affiliation(s)
- Sophie Rousseaux
- Université Grenoble Alpes, Inserm, CNRS, IAB, 38000, Grenoble, France
| | - Emie Seyve
- Université Grenoble Alpes, Inserm, CNRS, IAB, 38000, Grenoble, France
| | - Florent Chuffart
- Université Grenoble Alpes, Inserm, CNRS, IAB, 38000, Grenoble, France
| | | | - Meriem Benmerad
- Université Grenoble Alpes, Inserm, CNRS, IAB, 38000, Grenoble, France
| | - Marie-Aline Charles
- Université de Paris, Centre for Research in Epidemiology and Statistics (CRESS), INSERM, INRAE, Paris, France
| | - Anne Forhan
- Université de Paris, Centre for Research in Epidemiology and Statistics (CRESS), INSERM, INRAE, Paris, France
| | - Barbara Heude
- Université de Paris, Centre for Research in Epidemiology and Statistics (CRESS), INSERM, INRAE, Paris, France
| | - Valérie Siroux
- Université Grenoble Alpes, Inserm, CNRS, IAB, 38000, Grenoble, France
| | - Remy Slama
- Université Grenoble Alpes, Inserm, CNRS, IAB, 38000, Grenoble, France
| | - Jorg Tost
- Laboratory for Epigenetics and Environment, Centre National de Recherche en Génomique Humaine, CEA - Institut de Biologie François Jacob, Evry, France
| | - Daniel Vaiman
- Genomics, Epigenetics and Physiopathology of Reproduction, Institut Cochin, U1016 Inserm - UMR 8104 CNRS - Paris-Descartes University, Paris, France
| | - Saadi Khochbin
- Université Grenoble Alpes, Inserm, CNRS, IAB, 38000, Grenoble, France
| | - Johanna Lepeule
- Université Grenoble Alpes, Inserm, CNRS, IAB, 38000, Grenoble, France.
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13
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Legault LM, Doiron K, Lemieux A, Caron M, Chan D, Lopes FL, Bourque G, Sinnett D, McGraw S. Developmental genome-wide DNA methylation asymmetry between mouse placenta and embryo. Epigenetics 2020; 15:800-815. [PMID: 32056496 PMCID: PMC7518706 DOI: 10.1080/15592294.2020.1722922] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 01/03/2020] [Accepted: 01/15/2020] [Indexed: 12/27/2022] Open
Abstract
In early embryos, DNA methylation is remodelled to initiate the developmental program but for mostly unknown reasons, methylation marks are acquired unequally between embryonic and placental cells. To better understand this, we generated high-resolution DNA methylation maps of mouse mid-gestation (E10.5) embryo and placenta. We uncovered specific subtypes of differentially methylated regions (DMRs) that contribute directly to the developmental asymmetry existing between mid-gestation embryonic and placental DNA methylation patterns. We show that the asymmetry occurs rapidly during the acquisition of marks in the post-implanted conceptus (E3.5-E6.5), and that these patterns are long-lasting across subtypes of DMRs throughout prenatal development and in somatic tissues. We reveal that at the peri-implantation stages, the de novo methyltransferase activity of DNMT3B is the main driver of methylation marks on asymmetric DMRs, and that DNMT3B can largely compensate for lack of DNMT3A in the epiblast and extraembryonic ectoderm, whereas DNMT3A can only partially compensate in the absence of DNMT3B. However, as development progresses and as DNMT3A becomes the principal de novo methyltransferase, the compensatory DNA methylation mechanism of DNMT3B on DMRs becomes less effective.
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Affiliation(s)
- LM Legault
- Research Center of the CHU Sainte-Justine, Montreal, Canada
- Department of Biochemistry and Molecular Medicine, Université De Montréal, Montreal, Canada
| | - K Doiron
- Research Center of the CHU Sainte-Justine, Montreal, Canada
| | - A Lemieux
- Research Center of the CHU Sainte-Justine, Montreal, Canada
- Department of Biochemistry and Molecular Medicine, Université De Montréal, Montreal, Canada
| | - M Caron
- Research Center of the CHU Sainte-Justine, Montreal, Canada
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - D Chan
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - FL Lopes
- School of Veterinary Medicine, São Paulo State University (Unesp), Aracatuba, Brazil
| | - G Bourque
- Department of Human Genetics, McGill University, Montreal, Quebec, Canada
- McGill University and Genome Quebec Innovation Centre, Montreal, Quebec, Canada
- Canadian Center for Computational Genomics, Montreal, Quebec, Canada
| | - D Sinnett
- Research Center of the CHU Sainte-Justine, Montreal, Canada
- Department of Pediatrics, Université De Montréal, Montreal, Canada
| | - S McGraw
- Research Center of the CHU Sainte-Justine, Montreal, Canada
- Department of Biochemistry and Molecular Medicine, Université De Montréal, Montreal, Canada
- Department of Obstetrics and Gynecology, Université De Montréal, Montreal, Canada
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14
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Saad-Hussein A, Taha MM. Epigenetic study of global gene methylation in PON1, XRCC1 and GSTs different genotypes in rural and urban pesticide exposed workers. JOURNAL OF COMPLEMENTARY & INTEGRATIVE MEDICINE 2020; 17:/j/jcim.ahead-of-print/jcim-2019-0166/jcim-2019-0166.xml. [PMID: 32543462 DOI: 10.1515/jcim-2019-0166] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 11/11/2019] [Indexed: 11/15/2022]
Abstract
Background Epigenetic represents a study of occurred heritable gene expression changes without changing in the DNA sequence. It includes DNA methylation and miRNA expression that attract increasing attention as potential links between the genetic and environmental determinants of health and disease. Pesticide exposure is associated with adverse health effects and DNA methylation due to oxidative stress induced following its exposure. This study aimed to define the association of genetic polymorphisms of XRCC1, PON1, GSTP1 and GST genes with global genes DNA methylation in urban and rural occupationally pesticides exposed workers. Methods This study included 100 pesticides exposed workers; 50 rural sprayers (RE) and 50 urban researchers (UE). Controls included equal numbers. DNA methylation of global genes was evaluated by pyrosequencing assay. XRCC1, PON1 and GSTP1 genotyping were assessed by PCR-RFLP, and GST M1 and T1 were performed by PCR. Results The results of this study revealed that most genotypes in XRCC1, PON1, GSTP1 and GST genes were associated with LINE-1 hypomethylation among UE group. However, heterozygote genotypes (Gln-Arg and Ile-Val) in XRCC1 and GSTP1 genes, respectively, were associated with LINE-1 hypermethylation among UE compared with other corresponding genotypes. Only GSTT1 polymorphism recorded a significant change in percent methylation of Alu elements among urban and rural groups. Conclusion Urbanization could play an additional risk for epigenetic changes associated with pesticide exposure, and that could be attributed to the quality of life including their dietary habits, working and living in closed areas, and their exposure to extra pollutions emitted from urbanization sources.
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Affiliation(s)
- Amal Saad-Hussein
- Environmental & Occupational Medicine, National Research Centre, El-Behouth Street, Dokki Cairo, Egypt
| | - Mona Mohamed Taha
- Environmental & Occupational Medicine, National Research Centre, El-Behouth Street, Dokki Cairo, Egypt
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15
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Tekola-Ayele F, Zeng X, Ouidir M, Workalemahu T, Zhang C, Delahaye F, Wapner R. DNA methylation loci in placenta associated with birthweight and expression of genes relevant for early development and adult diseases. Clin Epigenetics 2020; 12:78. [PMID: 32493484 PMCID: PMC7268466 DOI: 10.1186/s13148-020-00873-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 05/21/2020] [Indexed: 02/03/2023] Open
Abstract
Background Birthweight marks an important milestone of health across the lifespan, including cardiometabolic disease risk in later life. The placenta, a transient organ at the maternal-fetal interface, regulates fetal growth. Identifying genetic loci where DNA methylation in placenta is associated with birthweight can unravel genomic pathways that are dysregulated in aberrant fetal growth and cardiometabolic diseases in later life. Results We performed placental epigenome-wide association study (EWAS) of birthweight in an ethnic diverse cohort of pregnant women (n = 301). Methylation at 15 cytosine-(phosphate)-guanine sites (CpGs) was associated with birthweight (false discovery rate (FDR) < 0.05). Methylation at four (26.7%) CpG sites was associated with placental transcript levels of 15 genes (FDR < 0.05), including genes known to be associated with adult lipid traits, inflammation and oxidative stress. Increased methylation at cg06155341 was associated with higher birthweight and lower FOSL1 expression, and lower FOSL1 expression was correlated with higher birthweight. Given the role of the FOSL1 transcription factor in regulating developmental processes at the maternal-fetal interface, epigenetic mechanisms at this locus may regulate fetal development. We demonstrated trans-tissue portability of methylation at four genes (MLLT1, PDE9A, ASAP2, and SLC20A2) implicated in birthweight by a previous study in cord blood. We also found that methylation changes known to be related to maternal underweight, preeclampsia and adult type 2 diabetes were associated with lower birthweight in placenta. Conclusion We identified novel placental DNA methylation changes associated with birthweight. Placental epigenetic mechanisms may underlie dysregulated fetal development and early origins of adult cardiometabolic diseases. Clinical trial registration ClinicalTrials.gov, NCT00912132
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Affiliation(s)
- Fasil Tekola-Ayele
- Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 6710B Rockledge Dr, room 3204, Bethesda, MD, 20892, USA.
| | - Xuehuo Zeng
- Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Marion Ouidir
- Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 6710B Rockledge Dr, room 3204, Bethesda, MD, 20892, USA
| | - Tsegaselassie Workalemahu
- Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 6710B Rockledge Dr, room 3204, Bethesda, MD, 20892, USA
| | - Cuilin Zhang
- Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 6710B Rockledge Dr, room 3204, Bethesda, MD, 20892, USA
| | - Fabien Delahaye
- Department of Genetics, Albert Einstein College of Medicine, Bronx, New York, USA.,UMR 1283, Institut Pasteur de Lille, Lille, France
| | - Ronald Wapner
- Department of Obstetrics and Gynecology, Columbia University, New York, NY, USA
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16
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Perera BP, Faulk C, Svoboda LK, Goodrich JM, Dolinoy DC. The role of environmental exposures and the epigenome in health and disease. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2020; 61:176-192. [PMID: 31177562 PMCID: PMC7252203 DOI: 10.1002/em.22311] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 05/29/2019] [Accepted: 06/03/2019] [Indexed: 05/02/2023]
Abstract
The genetic material of every organism exists within the context of regulatory networks that govern gene expression, collectively called the epigenome. Epigenetics has taken center stage in the study of diseases such as cancer and diabetes, but its integration into the field of environmental health is still emerging. As the Environmental Mutagenesis and Genomics Society (EMGS) celebrates its 50th Anniversary this year, we have come together to review and summarize the seminal advances in the field of environmental epigenomics. Specifically, we focus on the role epigenetics may play in multigenerational and transgenerational transmission of environmentally induced health effects. We also summarize state of the art techniques for evaluating the epigenome, environmental epigenetic analysis, and the emerging field of epigenome editing. Finally, we evaluate transposon epigenetics as they relate to environmental exposures and explore the role of noncoding RNA as biomarkers of environmental exposures. Although the field has advanced over the past several decades, including being recognized by EMGS with its own Special Interest Group, recently renamed Epigenomics, we are excited about the opportunities for environmental epigenetic science in the next 50 years. Environ. Mol. Mutagen. 61:176-192, 2020. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Bambarendage P.U. Perera
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan
| | - Christopher Faulk
- Department of Animal Sciences, University of Minnesota, St. Paul, Minnesota
| | - Laurie K. Svoboda
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan
| | - Jaclyn M. Goodrich
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan
| | - Dana C. Dolinoy
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan
- Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan
- Correspondence to: Dana C. Dolinoy, Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan.
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17
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Del Gobbo GF, Konwar C, Robinson WP. The significance of the placental genome and methylome in fetal and maternal health. Hum Genet 2019; 139:1183-1196. [PMID: 31555906 DOI: 10.1007/s00439-019-02058-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Accepted: 08/29/2019] [Indexed: 01/15/2023]
Abstract
The placenta is a crucial organ for supporting a healthy pregnancy, and defective development or function of the placenta is implicated in a number of complications of pregnancy that affect both maternal and fetal health, including maternal preeclampsia, fetal growth restriction, and spontaneous preterm birth. In this review, we highlight the role of the placental genome in mediating fetal and maternal health by discussing the impact of a variety of genetic alterations, from large whole-chromosome aneuploidies to single-nucleotide variants, on placental development and function. We also discuss the placental methylome in relation to its potential applications for refining diagnosis, predicting pathology, and identifying genetic variants with potential functional significance. We conclude that understanding the influence of the placental genome on common placental-mediated pathologies is critical to improving perinatal health outcomes.
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Affiliation(s)
- Giulia F Del Gobbo
- BC Children's Hospital Research Institute, 950 West 28th Ave, Vancouver, BC, V5Z 4H4, Canada.,Department of Medical Genetics, University of British Columbia, 4500 Oak Street, Vancouver, BC, V6H 3N1, Canada
| | - Chaini Konwar
- BC Children's Hospital Research Institute, 950 West 28th Ave, Vancouver, BC, V5Z 4H4, Canada.,Department of Medical Genetics, University of British Columbia, 4500 Oak Street, Vancouver, BC, V6H 3N1, Canada
| | - Wendy P Robinson
- BC Children's Hospital Research Institute, 950 West 28th Ave, Vancouver, BC, V5Z 4H4, Canada. .,Department of Medical Genetics, University of British Columbia, 4500 Oak Street, Vancouver, BC, V6H 3N1, Canada.
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18
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Apicella C, Ruano CSM, Méhats C, Miralles F, Vaiman D. The Role of Epigenetics in Placental Development and the Etiology of Preeclampsia. Int J Mol Sci 2019; 20:ijms20112837. [PMID: 31212604 PMCID: PMC6600551 DOI: 10.3390/ijms20112837] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 06/03/2019] [Accepted: 06/03/2019] [Indexed: 12/12/2022] Open
Abstract
In this review, we comprehensively present the function of epigenetic regulations in normal placental development as well as in a prominent disease of placental origin, preeclampsia (PE). We describe current progress concerning the impact of DNA methylation, non-coding RNA (with a special emphasis on long non-coding RNA (lncRNA) and microRNA (miRNA)) and more marginally histone post-translational modifications, in the processes leading to normal and abnormal placental function. We also explore the potential use of epigenetic marks circulating in the maternal blood flow as putative biomarkers able to prognosticate the onset of PE, as well as classifying it according to its severity. The correlation between epigenetic marks and impacts on gene expression is systematically evaluated for the different epigenetic marks analyzed.
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Affiliation(s)
- Clara Apicella
- Institut Cochin, U1016 INSERM, UMR8104 CNRS, Université Paris Descartes, 24 rue du faubourg St Jacques, 75014 Paris, France.
| | - Camino S M Ruano
- Institut Cochin, U1016 INSERM, UMR8104 CNRS, Université Paris Descartes, 24 rue du faubourg St Jacques, 75014 Paris, France.
| | - Céline Méhats
- Institut Cochin, U1016 INSERM, UMR8104 CNRS, Université Paris Descartes, 24 rue du faubourg St Jacques, 75014 Paris, France.
| | - Francisco Miralles
- Institut Cochin, U1016 INSERM, UMR8104 CNRS, Université Paris Descartes, 24 rue du faubourg St Jacques, 75014 Paris, France.
| | - Daniel Vaiman
- Institut Cochin, U1016 INSERM, UMR8104 CNRS, Université Paris Descartes, 24 rue du faubourg St Jacques, 75014 Paris, France.
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19
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Li S, Chen M, Li Y, Tollefsbol TO. Prenatal epigenetics diets play protective roles against environmental pollution. Clin Epigenetics 2019; 11:82. [PMID: 31097039 PMCID: PMC6524340 DOI: 10.1186/s13148-019-0659-4] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 03/27/2019] [Indexed: 12/12/2022] Open
Abstract
It is thought that germ cells and preimplantation embryos during development are most susceptible to endogenous and exogenous environmental factors because the epigenome in those cells is undergoing dramatic elimination and reconstruction. Exposure to environmental factors such as nutrition, climate, stress, pathogens, toxins, and even social behavior during gametogenesis and early embryogenesis has been shown to influence disease susceptibility in the offspring. Early-life epigenetic modifications, which determine the expression of genetic information stored in the genome, are viewed as one of the general mechanisms linking prenatal exposure and phenotypic changes later in life. From atmospheric pollution, endocrine-disrupting chemicals to heavy metals, research increasingly suggests that environmental pollutions have already produced significant consequences on human health. Moreover, mounting evidence now links such pollution to relevant modification in the epigenome. The epigenetics diet, referring to a class of bioactive dietary compounds such as isothiocyanates in broccoli, genistein in soybean, resveratrol in grape, epigallocatechin-3-gallate in green tea, and ascorbic acid in fruits, has been shown to modify the epigenome leading to beneficial health outcomes. This review will primarily focus on the causes and consequences of prenatal environment pollution exposure on the epigenome, and the potential protective role of the epigenetics diet, which could play a central role in neutralizing epigenomic aberrations against environmental pollutions.
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Affiliation(s)
- Shizhao Li
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Min Chen
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Yuanyuan Li
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, AL, USA.
- Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL, USA.
- Nutrition Obesity Research Center, University of Alabama at Birmingham, Birmingham, AL, USA.
| | - Trygve O Tollefsbol
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL, USA.
- Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL, USA.
- Nutrition Obesity Research Center, University of Alabama at Birmingham, Birmingham, AL, USA.
- Comprehensive Center for Healthy Aging, University of Alabama at Birmingham, Birmingham, AL, USA.
- Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL, USA.
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20
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Wilson RL, François M, Jankovic-Karasoulos T, McAninch D, McCullough D, Leifert WR, Roberts CT, Bianco-Miotto T. Characterization of 5-methylcytosine and 5-hydroxymethylcytosine in human placenta cell types across gestation. Epigenetics 2019; 14:660-671. [PMID: 31038385 DOI: 10.1080/15592294.2019.1609866] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The placenta is an important organ in pregnancy, however, very little is understood about placental development at a molecular level. This includes the role of epigenetic mechanisms and how they change throughout gestation. DNA methylation studies in this organ are complicated by the different cell types that make up the placenta, each with their own unique transcriptome and epigenome. Placental dysfunction is often associated with pregnancy complications such as preeclampsia (PE). Aberrant DNA methylation in the placenta has been identified in pregnancy complications. We used immunohistochemistry (IHC) and immunofluorescence (IF) to localize 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) in placenta tissue from first and second trimester as well as uncomplicated term and PE samples. IHC analysis of whole placental tissues showed 5-mC increased across gestation. When cytotrophoblasts (CTB) and syncytiotrophoblasts (STB) were isolated and assessed using IF, both 5-mC and 5-hmC increased in term CTBs compared to first/second-trimester samples. Staining intensity of 5-hmC was higher in first/second trimester STBs compared to CTBs (P = 0.0011). Finally, IHC staining of term tissue from PE and uncomplicated pregnancies revealed higher 5-mC staining intensity in placentas from PE pregnancies (P = 0.028). Our study has shown increased 5-mC and 5-hmC staining intensities across gestation and differed between two trophoblast populations. Differences in DNA methylation profiles between placental cell types may be indicative of different functions and requires further study to elucidate what changes accompany placental pathologies.
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Affiliation(s)
- Rebecca L Wilson
- a Center for Fetal and Placental Research , Cincinnati Children's Hospital and Medical Research Center , Cincinnati , OH , USA.,b Adelaide Medical School , University of Adelaide , Adelaide , Australia.,c Robinson Research Institute , University of Adelaide , Adelaide , Australia
| | - Maxime François
- d CSIRO Health and Biosecurity , Future Science Platforms Probing Biosystems , Adelaide , Australia.,e School of Biological Sciences , University of Adelaide , Adelaide , Australia
| | - Tanja Jankovic-Karasoulos
- b Adelaide Medical School , University of Adelaide , Adelaide , Australia.,c Robinson Research Institute , University of Adelaide , Adelaide , Australia
| | - Dale McAninch
- b Adelaide Medical School , University of Adelaide , Adelaide , Australia.,c Robinson Research Institute , University of Adelaide , Adelaide , Australia
| | - Dylan McCullough
- b Adelaide Medical School , University of Adelaide , Adelaide , Australia.,c Robinson Research Institute , University of Adelaide , Adelaide , Australia
| | - Wayne R Leifert
- d CSIRO Health and Biosecurity , Future Science Platforms Probing Biosystems , Adelaide , Australia.,e School of Biological Sciences , University of Adelaide , Adelaide , Australia
| | - Claire T Roberts
- b Adelaide Medical School , University of Adelaide , Adelaide , Australia.,c Robinson Research Institute , University of Adelaide , Adelaide , Australia
| | - Tina Bianco-Miotto
- c Robinson Research Institute , University of Adelaide , Adelaide , Australia.,f School of Agriculture, Food and Wine, Waite Research Institute , University of Adelaide , Adelaide , Australia
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21
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Ariff A, Melton PE, Brennecke SP, Moses EK. Analysis of the Epigenome in Multiplex Pre-eclampsia Families Identifies SORD, DGKI, and ICA1 as Novel Candidate Risk Genes. Front Genet 2019; 10:227. [PMID: 30941163 PMCID: PMC6434177 DOI: 10.3389/fgene.2019.00227] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 02/28/2019] [Indexed: 01/04/2023] Open
Abstract
Pre-eclampsia is a serious heritable disorder that affects 5-8% of pregnancies worldwide. While classical genetic studies have identified several susceptibility genes they do not fully explain the heritability of pre-eclampsia. An additional contribution to risk can be quantified by examining the epigenome, in particular the methylome, which is a representation of interactions between environmental and genetic influences on the phenotype. Current array-based epigenetic studies only examine 2-5% of the methylome. Here, we used whole-genome bisulfite sequencing (WGBS) to determine the entire methylome of 13 individuals from two multiplex pre-eclampsia families, comprising one woman with eclampsia, six women with pre-eclampsia, four women with uncomplicated normotensive pregnancies and two male relatives. The analysis of WGBS profiles using two bioinformatics platforms, BSmooth and Bismark, revealed 18,909 differentially methylated CpGs and 4157 differentially methylated regions (DMRs) concordant in females. The methylation patterns support the involvement of previously reported candidate genes, including COL4A1, SLC2A4, PER3, FLT1, GPI, LCT, DDAH1, TGFB3, DLX5, and LRP1B. Statistical analysis of DMRs revealed three novel genes significantly correlated with pre-eclampsia: sorbitol dehydrogenase (SORD, p = 9.98 × 10-6), diacylglycerol kinase iota (DGKI, p = 2.52 × 10-5), and islet cell autoantigen 1 (ICA1, 7.54 × 10-3), demonstrating the potential of WGBS in families for elucidating the role of epigenome in pre-eclampsia and other complex diseases.
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Affiliation(s)
- Amir Ariff
- The Curtin UWA Centre for Genetic Origins of Health and Disease, Faculty of Health and Medical Sciences, Curtin University, The University of Western Australia, Perth, WA, Australia.,School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin University, Perth, WA, Australia
| | - Phillip E Melton
- The Curtin UWA Centre for Genetic Origins of Health and Disease, Faculty of Health and Medical Sciences, Curtin University, The University of Western Australia, Perth, WA, Australia.,School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin University, Perth, WA, Australia
| | - Shaun P Brennecke
- Department of Maternal-Fetal Medicine Pregnancy Research Centre, The Royal Women's Hospital, Melbourne, VIC, Australia.,Department of Obstetrics and Gynaecology, The University of Melbourne, Melbourne, VIC, Australia
| | - Eric K Moses
- The Curtin UWA Centre for Genetic Origins of Health and Disease, Faculty of Health and Medical Sciences, Curtin University, The University of Western Australia, Perth, WA, Australia.,School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin University, Perth, WA, Australia.,School of Biomedical Sciences, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia
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22
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McDade TW, Ryan CP, Jones MJ, Hoke MK, Borja J, Miller GE, Kuzawa CW, Kobor MS. Genome-wide analysis of DNA methylation in relation to socioeconomic status during development and early adulthood. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2019; 169:3-11. [PMID: 30771258 DOI: 10.1002/ajpa.23800] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 02/01/2019] [Accepted: 02/02/2019] [Indexed: 01/14/2023]
Abstract
OBJECTIVES Socioeconomic status (SES) is a powerful determinant of health, but the underlying biological mechanisms are poorly understood. This study investigates whether levels of DNA methylation at CpG sites across the genome are associated with SES in a cohort of young adults in the Philippines. METHODS DNA methylation was assayed with the Illumina HumanMethylation450 Bead Chip, in leukocytes from 489 participants in the Cebu Longitudinal Health and Nutrition Survey (mean age = 20.9 years). SES was measured in infancy/childhood and adulthood, and was based on composite measures of income, assets, and education. Genome-wide analysis of variable probes identified CpG sites significantly associated with SES after adjustment for multiple comparisons. Functional enrichment analysis was used to identify biological pathways associated with these sites. RESULTS A total of 2,546 CpG sites, across 1,537 annotated genes, were differentially methylated in association with SES. In comparison with high SES, low SES was associated with increased methylation at 1,777 sites, and decreased methylation at 769 sites. Functional enrichment analysis identified over-representation of biological pathways related to immune function, skeletal development, and development of the nervous system. CONCLUSIONS Socioeconomic status predicts DNA methylation at a large number of CpG sites across the genome. The scope of these associations is commensurate with the wide range of biological systems and health outcomes that are shaped by SES, and these findings suggest that DNA methylation may play an important role.
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Affiliation(s)
- Thomas W McDade
- Department of Anthropology, Northwestern University, Evanston, Illinois.,Institute for Policy Research, Northwestern University, Evanston, Illinois.,Child and Brain Development Program, Canadian Institute for Advanced Research, Toronto, Ontario, Canada
| | - Calen P Ryan
- Department of Anthropology, Northwestern University, Evanston, Illinois
| | - Meaghan J Jones
- Department of Medical Genetics, University of British Columbia.,BC Children's Hospital Research Institute.,Department of Biochemistry and Medical Genetics, University of Manitoba
| | - Morgan K Hoke
- Department of Anthropology, University of Pennsylvania, Philadelphia, Pennsylvania.,Population Studies Center, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Judith Borja
- USC-Office of Population Studies Foundation, Inc., University of San Carlos, Cebu City, Philippines.,Department of Nutrition and Dietetics, University of San Carlos, Cebu City, Philippines
| | - Gregory E Miller
- Institute for Policy Research, Northwestern University, Evanston, Illinois.,Department of Psychology, Northwestern University, Evanston, Illinois
| | - Christopher W Kuzawa
- Department of Anthropology, Northwestern University, Evanston, Illinois.,Institute for Policy Research, Northwestern University, Evanston, Illinois
| | - Michael S Kobor
- Child and Brain Development Program, Canadian Institute for Advanced Research, Toronto, Ontario, Canada.,Department of Medical Genetics, University of British Columbia.,BC Children's Hospital Research Institute
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23
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Alfano R, Herceg Z, Nawrot TS, Chadeau-Hyam M, Ghantous A, Plusquin M. The Impact of Air Pollution on Our Epigenome: How Far Is the Evidence? (A Systematic Review). Curr Environ Health Rep 2018; 5:544-578. [PMID: 30361985 DOI: 10.1007/s40572-018-0218-8] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
PURPOSE OF REVIEW This systematic review evaluated existing evidence linking air pollution exposure in humans to major epigenetic mechanisms: DNA methylation, microRNAs, long noncoding RNAs, and chromatin regulation. RECENT FINDINGS Eighty-two manuscripts were eligible, most of which were observational (85%), conducted in adults (66%) and based on DNA methylation (79%). Most observational studies, except panel, demonstrated modest effects of air pollution on the methylome. Panel and experimental studies revealed a relatively large number of significant methylome alterations, though based on smaller sample sizes. Particulate matter levels were positively associated in several studies with global or LINE-1 hypomethylation, a hallmark of several diseases, and with decondensed chromatin structure. Several air pollution species altered the DNA methylation clock, inducing accelerated biological aging. The causal nature of identified associations is not clear, however, especially that most originate from countries with low air pollution levels. Existing evidence, gaps, and perspectives are highlighted herein.
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Affiliation(s)
- Rossella Alfano
- Centre for Environmental Sciences, Hasselt University, Hasselt, Belgium
| | - Zdenko Herceg
- Epigenetics Group, International Agency for Research on Cancer (IARC), 150 Cours Albert-Thomas, 69008, Lyon, France
| | - Tim S Nawrot
- Centre for Environmental Sciences, Hasselt University, Hasselt, Belgium
- Environment & Health Unit, Leuven University, Leuven, Belgium
| | - Marc Chadeau-Hyam
- Department of Epidemiology and Biostatistics, The School of Public Health, Imperial College London, London, UK
| | - Akram Ghantous
- Epigenetics Group, International Agency for Research on Cancer (IARC), 150 Cours Albert-Thomas, 69008, Lyon, France.
| | - Michelle Plusquin
- Centre for Environmental Sciences, Hasselt University, Hasselt, Belgium.
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24
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Luyten LJ, Saenen ND, Janssen BG, Vrijens K, Plusquin M, Roels HA, Debacq-Chainiaux F, Nawrot TS. Air pollution and the fetal origin of disease: A systematic review of the molecular signatures of air pollution exposure in human placenta. ENVIRONMENTAL RESEARCH 2018; 166:310-323. [PMID: 29908461 DOI: 10.1016/j.envres.2018.03.025] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 03/13/2018] [Accepted: 03/14/2018] [Indexed: 05/24/2023]
Abstract
BACKGROUND Fetal development is a crucial window of susceptibility in which exposure-related alterations can be induced on the molecular level, leading to potential changes in metabolism and development. The placenta serves as a gatekeeper between mother and fetus, and is in contact with environmental stressors throughout pregnancy. This makes the placenta as a temporary organ an informative non-invasive matrix suitable to investigate omics-related aberrations in association with in utero exposures such as ambient air pollution. OBJECTIVES To summarize and discuss the current evidence and define the gaps of knowledge concerning human placental -omics markers in association with prenatal exposure to ambient air pollution. METHODS Two investigators independently searched the PubMed, ScienceDirect, and Scopus databases to identify all studies published until January 2017 with an emphasis on epidemiological research on prenatal exposure to ambient air pollution and the effect on placental -omics signatures. RESULTS From the initial 386 articles, 25 were retained following an a priori set inclusion and exclusion criteria. We identified eleven studies on the genome, two on the transcriptome, five on the epigenome, five on the proteome category, one study with both genomic and proteomic topics, and one study with both genomic and transcriptomic topics. Six studies discussed the triple relationship between exposure to air pollution during pregnancy, the associated placental -omics marker(s), and the potential effect on disease development later in life. So far, no metabolomic or exposomic data discussing associations between the placenta and prenatal exposure to air pollution have been published. CONCLUSIONS Integration of placental biomarkers in an environmental epidemiological context enables researchers to address fundamental questions essential in unraveling the fetal origin of disease and helps to better define the pregnancy exposome of air pollution.
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Affiliation(s)
- Leen J Luyten
- Centre for Environmental Sciences, Hasselt University, Hasselt, Belgium; Unité de Recherche en Biologie Cellulaire (URBC) - Namur Research Institute for Life Sciences (Narilis), University of Namur, Belgium
| | - Nelly D Saenen
- Centre for Environmental Sciences, Hasselt University, Hasselt, Belgium
| | - Bram G Janssen
- Centre for Environmental Sciences, Hasselt University, Hasselt, Belgium
| | - Karen Vrijens
- Centre for Environmental Sciences, Hasselt University, Hasselt, Belgium
| | - Michelle Plusquin
- Centre for Environmental Sciences, Hasselt University, Hasselt, Belgium
| | - Harry A Roels
- Centre for Environmental Sciences, Hasselt University, Hasselt, Belgium; Louvain Centre for Toxicology and Applied Pharmacology, Université catholique de Louvain, Brussels, Belgium
| | - Florence Debacq-Chainiaux
- Unité de Recherche en Biologie Cellulaire (URBC) - Namur Research Institute for Life Sciences (Narilis), University of Namur, Belgium
| | - Tim S Nawrot
- Centre for Environmental Sciences, Hasselt University, Hasselt, Belgium; Department of Public Health & Primary Care, Occupational and Environmental Medicine, Leuven University (KULeuven), Leuven, Belgium.
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25
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Than NG, Romero R, Tarca AL, Kekesi KA, Xu Y, Xu Z, Juhasz K, Bhatti G, Leavitt RJ, Gelencser Z, Palhalmi J, Chung TH, Gyorffy BA, Orosz L, Demeter A, Szecsi A, Hunyadi-Gulyas E, Darula Z, Simor A, Eder K, Szabo S, Topping V, El-Azzamy H, LaJeunesse C, Balogh A, Szalai G, Land S, Torok O, Dong Z, Kovalszky I, Falus A, Meiri H, Draghici S, Hassan SS, Chaiworapongsa T, Krispin M, Knöfler M, Erez O, Burton GJ, Kim CJ, Juhasz G, Papp Z. Integrated Systems Biology Approach Identifies Novel Maternal and Placental Pathways of Preeclampsia. Front Immunol 2018; 9:1661. [PMID: 30135684 PMCID: PMC6092567 DOI: 10.3389/fimmu.2018.01661] [Citation(s) in RCA: 123] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 07/04/2018] [Indexed: 12/13/2022] Open
Abstract
Preeclampsia is a disease of the mother, fetus, and placenta, and the gaps in our understanding of the complex interactions among their respective disease pathways preclude successful treatment and prevention. The placenta has a key role in the pathogenesis of the terminal pathway characterized by exaggerated maternal systemic inflammation, generalized endothelial damage, hypertension, and proteinuria. This sine qua non of preeclampsia may be triggered by distinct underlying mechanisms that occur at early stages of pregnancy and induce different phenotypes. To gain insights into these molecular pathways, we employed a systems biology approach and integrated different "omics," clinical, placental, and functional data from patients with distinct phenotypes of preeclampsia. First trimester maternal blood proteomics uncovered an altered abundance of proteins of the renin-angiotensin and immune systems, complement, and coagulation cascades in patients with term or preterm preeclampsia. Moreover, first trimester maternal blood from preterm preeclamptic patients in vitro dysregulated trophoblastic gene expression. Placental transcriptomics of women with preterm preeclampsia identified distinct gene modules associated with maternal or fetal disease. Placental "virtual" liquid biopsy showed that the dysregulation of these disease gene modules originates during the first trimester. In vitro experiments on hub transcription factors of these gene modules demonstrated that DNA hypermethylation in the regulatory region of ZNF554 leads to gene down-regulation and impaired trophoblast invasion, while BCL6 and ARNT2 up-regulation sensitizes the trophoblast to ischemia, hallmarks of preterm preeclampsia. In summary, our data suggest that there are distinct maternal and placental disease pathways, and their interaction influences the clinical presentation of preeclampsia. The activation of maternal disease pathways can be detected in all phenotypes of preeclampsia earlier and upstream of placental dysfunction, not only downstream as described before, and distinct placental disease pathways are superimposed on these maternal pathways. This is a paradigm shift, which, in agreement with epidemiological studies, warrants for the central pathologic role of preexisting maternal diseases or perturbed maternal-fetal-placental immune interactions in preeclampsia. The description of these novel pathways in the "molecular phase" of preeclampsia and the identification of their hub molecules may enable timely molecular characterization of patients with distinct preeclampsia phenotypes.
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Affiliation(s)
- Nandor Gabor Than
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, MI, United States
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
- Maternity Private Department, Kutvolgyi Clinical Block, Semmelweis University, Budapest, Hungary
- First Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary
| | - Roberto Romero
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI, United States
- Department of Epidemiology and Biostatistics, Michigan State University, East Lansing, MI, United States
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI, United States
| | - Adi Laurentiu Tarca
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, MI, United States
- Department of Computer Science, College of Engineering, Wayne State University, Detroit, MI, United States
| | - Katalin Adrienna Kekesi
- Laboratory of Proteomics, Department of Physiology and Neurobiology, ELTE Eotvos Lorand University, Budapest, Hungary
| | - Yi Xu
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
| | - Zhonghui Xu
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Channing Division of Network Medicine, Brigham and Women’s Hospital, Harvard University, Boston, MA, United States
| | - Kata Juhasz
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Gaurav Bhatti
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
| | | | - Zsolt Gelencser
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Janos Palhalmi
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | | | - Balazs Andras Gyorffy
- Laboratory of Proteomics, Department of Physiology and Neurobiology, ELTE Eotvos Lorand University, Budapest, Hungary
| | - Laszlo Orosz
- Department of Obstetrics and Gynaecology, University of Debrecen, Debrecen, Hungary
| | - Amanda Demeter
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Anett Szecsi
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Eva Hunyadi-Gulyas
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Zsuzsanna Darula
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Attila Simor
- Laboratory of Proteomics, Department of Physiology and Neurobiology, ELTE Eotvos Lorand University, Budapest, Hungary
| | - Katalin Eder
- Department of Genetics, Cell and Immunobiology, Semmelweis University, Budapest, Hungary
| | - Szilvia Szabo
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
- Department of Morphology and Physiology, Semmelweis University, Budapest, Hungary
| | - Vanessa Topping
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
| | - Haidy El-Azzamy
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
| | - Christopher LaJeunesse
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
| | - Andrea Balogh
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Gabor Szalai
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Susan Land
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI, United States
| | - Olga Torok
- Department of Obstetrics and Gynaecology, University of Debrecen, Debrecen, Hungary
| | - Zhong Dong
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
| | - Ilona Kovalszky
- First Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary
| | - Andras Falus
- Department of Genetics, Cell and Immunobiology, Semmelweis University, Budapest, Hungary
| | | | - Sorin Draghici
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI, United States
- Department of Clinical and Translational Science, Wayne State University, Detroit, MI, United States
| | - Sonia S. Hassan
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, MI, United States
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, United States
| | - Tinnakorn Chaiworapongsa
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, MI, United States
| | | | - Martin Knöfler
- Department of Obstetrics and Gynecology, Medical University of Vienna, Vienna, Austria
| | - Offer Erez
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, MI, United States
- Department of Obstetrics and Gynecology, Soroka University Medical Center School of Medicine, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Graham J. Burton
- Centre for Trophoblast Research, Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Chong Jai Kim
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Department of Pathology, Wayne State University School of Medicine, Detroit, MI, United States
- Department of Pathology, Asan Medical Center, University of Ulsan, Seoul, South Korea
| | - Gabor Juhasz
- Laboratory of Proteomics, Department of Physiology and Neurobiology, ELTE Eotvos Lorand University, Budapest, Hungary
| | - Zoltan Papp
- Maternity Private Department, Kutvolgyi Clinical Block, Semmelweis University, Budapest, Hungary
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Strakovsky RS, Schantz SL. Impacts of bisphenol A (BPA) and phthalate exposures on epigenetic outcomes in the human placenta. ENVIRONMENTAL EPIGENETICS 2018; 4:dvy022. [PMID: 30210810 PMCID: PMC6128378 DOI: 10.1093/eep/dvy022] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Revised: 07/18/2018] [Accepted: 07/20/2018] [Indexed: 05/18/2023]
Abstract
The placenta guides fetal growth and development. Bisphenol A (BPA) and phthalates are widespread environmental contaminants and endocrine disruptors, and the placental epigenetic response to these chemicals is an area of growing research interest. Therefore, our objective was to summarize research linking BPA or phthalate exposure to placental outcomes in human pregnancies, with a particular focus on epigenetic endpoints. In PubMed, studies were selected for review (without limiting start date and ending on 1 May 2018) if they reported any direct effects of BPA or phthalates on the placenta in humans. Collectively, available studies suggest that BPA and phthalate exposures are associated with changes to placental micro-RNA expression, DNA methylation, and genomic imprinting. Furthermore, several studies suggest that fetal sex may be an important modifier of placental outcomes in response to these chemicals. Studies in humans demonstrate associations of BPA and phthalate exposure with adverse placental outcomes. Moving forward, more studies should consider sex differences (termed "placental sex") in the measured outcomes, and should utilize appropriate statistical approaches to assess modification by fetal sex. Furthermore, more consistent sample collection and molecular outcome assessment paradigms will be indispensable for making progress in the field. These advances, together with improved non-invasive tools for measuring placental function and outcomes across pregnancy, will be critical for understanding the mechanisms driving placental epigenetic disruption in response to BPA and phthalates, and how these disruptions translate into placental and fetal health.
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Affiliation(s)
- Rita S Strakovsky
- The Department of Food Science and Human Nutrition, Michigan State University, 236C Trout Building, 469 Wilson Road, East Lansing, MI, USA
- Correspondence address. The Department of Food Science and Human Nutrition, Michigan State University, 236C Trout Building, 469 Wilson Road, East Lansing, MI 48823, USA. Tel: 517-353-3352; Fax: 517-353-8963; E-mail:
| | - Susan L Schantz
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, 405 N. Mathews Ave, Urbana, IL, USA
- Department of Comparative Biosciences, 2347 Beckman Institute, University of Illinois Urbana-Champaign, 405 N. Mathews Ave, Urbana, IL, USA
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Coker ES, Gunier R, Huen K, Holland N, Eskenazi B. DNA methylation and socioeconomic status in a Mexican-American birth cohort. Clin Epigenetics 2018; 10:61. [PMID: 29760810 PMCID: PMC5941629 DOI: 10.1186/s13148-018-0494-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 04/25/2018] [Indexed: 11/25/2022] Open
Abstract
Background Maternal social environmental stressors during pregnancy are associated with adverse birth and child developmental outcomes, and epigenetics has been proposed as a possible mechanism for such relationships. Methods In a Mexican-American birth cohort of 241 maternal-infant pairs, cord blood samples were measured for repeat element DNA methylation (LINE-1 and Alu). Linear mixed effects regression was used to model associations between indicators of the social environment (low household income and education, neighborhood-level characteristics) and repeat element methylation. Results from a dietary questionnaire were also used to assess the interaction between maternal diet quality and the social environment on markers of repeat element DNA methylation. Results After adjusting for confounders, living in the most impoverished neighborhoods was associated with higher cord blood LINE-1 methylation (β = 0.78, 95%CI 0.06, 1.50, p = 0.03). No other neighborhood-, household-, or individual-level socioeconomic indicators were significantly associated with repeat element methylation. We observed a statistical trend showing that positive association between neighborhood poverty and LINE-1 methylation was strongest in cord blood of infants whose mothers reported better diet quality during pregnancy (pinteraction = 0.12). Conclusion Our findings indicate a small yet unexpected positive association between neighborhood-level poverty during pregnancy and methylation of repetitive element DNA in infant cord blood and that this association is possibly modified by diet quality during pregnancy. However, our null findings for other adverse SES indicators do not provide strong evidence for an adverse association between early-life socioeconomic environment and repeat element DNA methylation in infants.
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Affiliation(s)
- Eric S. Coker
- Center for Environmental Research and Children’s Health (CERCH), School of Public Health, University of California, Berkeley, CA USA
- Berkeley, USA
| | - Robert Gunier
- Center for Environmental Research and Children’s Health (CERCH), School of Public Health, University of California, Berkeley, CA USA
- Berkeley, USA
| | - Karen Huen
- Center for Environmental Research and Children’s Health (CERCH), School of Public Health, University of California, Berkeley, CA USA
- Richmond, USA
| | - Nina Holland
- Center for Environmental Research and Children’s Health (CERCH), School of Public Health, University of California, Berkeley, CA USA
- Richmond, USA
| | - Brenda Eskenazi
- Center for Environmental Research and Children’s Health (CERCH), School of Public Health, University of California, Berkeley, CA USA
- Berkeley, USA
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28
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Rattanapan Y, Korkiatsakul V, Kongruang A, Chareonsirisuthigul T, Rerkamnuaychoke B, Wongkularb A, Wilailak S. EGFL7 and RASSF1 promoter hypermethylation in epithelial ovarian cancer. Cancer Genet 2018; 224-225:37-40. [PMID: 29778234 DOI: 10.1016/j.cancergen.2018.04.117] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 03/06/2018] [Accepted: 04/13/2018] [Indexed: 01/22/2023]
Abstract
DNA methylation is one of the epigenetic mechanisms associated with gene expression and plays a key role as in activation and deactivation of oncogenes and tumor suppressor genes, respectively. This study employed DNA methylation array to identify methylated genes which are highly correlated with various phenotypes of epithelial ovarian cancer (EOC) in Thai patients and to quantify promoter CpG-island methylation of candidate genes. Tissues from patients with serous and non-serous EOC showed significantly higher promoter methylation of EGFL7 and RASSF1 compared to benign cases. These results indicate the potential of investigating promoter CpG-island methylation of cancer-associated genes as biomarkers of disease progression and even possibly of early detection.
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Affiliation(s)
- Yanisa Rattanapan
- Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, 10400, Thailand
| | - Veerawat Korkiatsakul
- Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, 10400, Thailand
| | - Adcharee Kongruang
- Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, 10400, Thailand
| | - Takol Chareonsirisuthigul
- Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, 10400, Thailand.
| | - Budsaba Rerkamnuaychoke
- Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, 10400, Thailand
| | - Anna Wongkularb
- Department of Obstetrics and Gynecology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, 10400, Thailand
| | - Sarikapan Wilailak
- Department of Obstetrics and Gynecology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, 10400, Thailand
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29
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Wilson SL, Robinson WP. Utility of DNA methylation to assess placental health. Placenta 2018; 64 Suppl 1:S23-S28. [DOI: 10.1016/j.placenta.2017.12.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 12/12/2017] [Accepted: 12/13/2017] [Indexed: 12/18/2022]
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30
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Del Gobbo GF, Price EM, Hanna CW, Robinson WP. No evidence for association of MTHFR 677C>T and 1298A>C variants with placental DNA methylation. Clin Epigenetics 2018; 10:34. [PMID: 29564022 PMCID: PMC5851070 DOI: 10.1186/s13148-018-0468-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 03/01/2018] [Indexed: 01/30/2023] Open
Abstract
Background 5,10-Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme in one-carbon metabolism that ensures the availability of methyl groups for methylation reactions. Two single-nucleotide polymorphisms (SNPs) in the MTHFR gene, 677C>T and 1298A>C, result in a thermolabile enzyme with reduced function. These variants, in both the maternal and/or fetal genes, have been associated with pregnancy complications including miscarriage, neural tube defects (NTDs), and preeclampsia (PE), perhaps due to altered capacity for DNA methylation (DNAm). In this study, we assessed the association between MTHFR 677TT and 1298CC genotypes and risk of NTDs, PE, or normotensive intrauterine growth restriction (nIUGR). Additionally, we assessed whether these high-risk genotypes are associated with altered DNAm in the placenta. Results In 303 placentas screened for this study, we observed no significant association between the occurrence of NTDs (N = 55), PE (early-onset: N = 28, late-onset: N = 20), or nIUGR (N = 21) and placental (fetal) MTHFR 677TT or 1298CC genotypes compared to healthy pregnancies (N = 179), though a trend of increased 677TT genotype in PE/IUGR together was observed (OR 2.53, p = 0.048). DNAm was profiled in 10 high-risk 677 (677TT + 1298AA), 10 high-risk 1298 (677CC + 1298CC), and 10 reference (677CC + 1298AA) genotype placentas. Linear modeling identified no significantly differentially methylated sites between high-risk 677 or 1298 and reference placentas at a false discovery rate < 0.05 and Δβ ≥ 0.05 using the Illumina Infinium HumanMethylation450 BeadChip. Using a differentially methylated region analysis or separating cytosine-guanine dinucleotides (CpGs) by CpG density to reduce multiple comparisons also did not identify differential methylation. Additionally, there was no consistent evidence for altered methylation of repetitive DNA between high-risk and reference placentas. Conclusions We conclude that large-scale, genome-wide disruption in DNAm does not occur in placentas with the high-risk MTHFR 677TT or 1298CC genotypes. Furthermore, there was no evidence for an association of the 1298CC genotype and only a tendency to higher 677TT in pregnancy complications of PE/IUGR. This may be due to small sample sizes or folate repletion in our Canadian population attenuating effects of the high-risk MTHFR variants. However, given our results and the conflicting results in the literature, investigations into alternative mechanisms that may explain the link between MTHFR variants and pregnancy complications, or in populations at risk of folate deficiencies, are warranted. Electronic supplementary material The online version of this article (10.1186/s13148-018-0468-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Giulia F Del Gobbo
- 1BC Children's Hospital Research Institute, 950 W 28th Ave, Vancouver, BC V5Z 4H4 Canada.,2Department of Medical Genetics, University of British Columbia, 4500 Oak St, Vancouver, BC V6H 3N1 Canada
| | - E Magda Price
- 1BC Children's Hospital Research Institute, 950 W 28th Ave, Vancouver, BC V5Z 4H4 Canada.,2Department of Medical Genetics, University of British Columbia, 4500 Oak St, Vancouver, BC V6H 3N1 Canada
| | - Courtney W Hanna
- 3Epigenetics Programme, Babraham Institute, Cambridge, CB22 3AT UK.,4Centre for Trophoblast Research, University of Cambridge, Cambridge, CB2 3EG UK
| | - Wendy P Robinson
- 1BC Children's Hospital Research Institute, 950 W 28th Ave, Vancouver, BC V5Z 4H4 Canada.,2Department of Medical Genetics, University of British Columbia, 4500 Oak St, Vancouver, BC V6H 3N1 Canada.,5Child and Family Research Institute, Room 2082, 950 W 28th Avenue, Vancouver, BC V5Z 4H4 Canada
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Zheng Y, Joyce BT, Liu L, Zhang Z, Kibbe WA, Zhang W, Hou L. Prediction of genome-wide DNA methylation in repetitive elements. Nucleic Acids Res 2017; 45:8697-8711. [PMID: 28911103 PMCID: PMC5587781 DOI: 10.1093/nar/gkx587] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 06/28/2017] [Indexed: 12/16/2022] Open
Abstract
DNA methylation in repetitive elements (RE) suppresses their mobility and maintains genomic stability, and decreases in it are frequently observed in tumor and/or surrogate tissues. Averaging methylation across RE in genome is widely used to quantify global methylation. However, methylation may vary in specific RE and play diverse roles in disease development, thus averaging methylation across RE may lose significant biological information. The ambiguous mapping of short reads by and high cost of current bisulfite sequencing platforms make them impractical for quantifying locus-specific RE methylation. Although microarray-based approaches (particularly Illumina's Infinium methylation arrays) provide cost-effective and robust genome-wide methylation quantification, the number of interrogated CpGs in RE remains limited. We report a random forest-based algorithm (and corresponding R package, REMP) that can accurately predict genome-wide locus-specific RE methylation based on Infinium array profiling data. We validated its prediction performance using alternative sequencing and microarray data. Testing its clinical utility with The Cancer Genome Atlas data demonstrated that our algorithm offers more comprehensively extended locus-specific RE methylation information that can be readily applied to large human studies in a cost-effective manner. Our work has the potential to improve our understanding of the role of global methylation in human diseases, especially cancer.
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Affiliation(s)
- Yinan Zheng
- Center for Population Epigenetics, Robert H. Lurie Comprehensive Cancer Center and Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.,Division of Health and Biomedical Informatics, Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Brian T Joyce
- Center for Population Epigenetics, Robert H. Lurie Comprehensive Cancer Center and Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Lei Liu
- Center for Population Epigenetics, Robert H. Lurie Comprehensive Cancer Center and Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Zhou Zhang
- Center for Population Epigenetics, Robert H. Lurie Comprehensive Cancer Center and Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.,Division of Health and Biomedical Informatics, Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Warren A Kibbe
- Center for Biomedical Informatics and Information Technology, National Cancer Institute, Rockville, MD 20850, USA
| | - Wei Zhang
- Center for Population Epigenetics, Robert H. Lurie Comprehensive Cancer Center and Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Lifang Hou
- Center for Population Epigenetics, Robert H. Lurie Comprehensive Cancer Center and Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
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32
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Social and physical environments early in development predict DNA methylation of inflammatory genes in young adulthood. Proc Natl Acad Sci U S A 2017; 114:7611-7616. [PMID: 28673994 DOI: 10.1073/pnas.1620661114] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Chronic inflammation contributes to a wide range of human diseases, and environments in infancy and childhood are important determinants of inflammatory phenotypes. The underlying biological mechanisms connecting early environments with the regulation of inflammation in adulthood are not known, but epigenetic processes are plausible candidates. We tested the hypothesis that patterns of DNA methylation (DNAm) in inflammatory genes in young adulthood would be predicted by early life nutritional, microbial, and psychosocial exposures previously associated with levels of inflammation. Data come from a population-based longitudinal birth cohort study in metropolitan Cebu, the Philippines, and DNAm was characterized in whole blood samples from 494 participants (age 20-22 y). Analyses focused on probes in 114 target genes involved in the regulation of inflammation, and we identified 10 sites across nine genes where the level of DNAm was significantly predicted by the following variables: household socioeconomic status in childhood, extended absence of a parent in childhood, exposure to animal feces in infancy, birth in the dry season, or duration of exclusive breastfeeding. To evaluate the biological significance of these sites, we tested for associations with a panel of inflammatory biomarkers measured in plasma obtained at the same age as DNAm assessment. Three sites predicted elevated inflammation, and one site predicted lower inflammation, consistent with the interpretation that levels of DNAm at these sites are functionally relevant. This pattern of results points toward DNAm as a potentially important biological mechanism through which developmental environments shape inflammatory phenotypes across the life course.
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Barchitta M, Quattrocchi A, Maugeri A, Barone G, Mazzoleni P, Catalfo A, De Guidi G, Iemmolo M, Crimi N, Agodi A. Integrated approach of nutritional and molecular epidemiology, mineralogical and chemical pollutant characterisation: the protocol of a cross-sectional study in women. BMJ Open 2017; 7:e014756. [PMID: 28377395 PMCID: PMC5387935 DOI: 10.1136/bmjopen-2016-014756] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
INTRODUCTION Environmentally-related health and disease are the result of the exposome, the totality of a person's environmental exposures, from all sources and routes, across their lifespan. Epigenetic phenomena, including DNA methylation, can be potentially modified by environmental and lifestyle factors, and result in environmental reprogramming of the genome for exposed individuals and for future generations of offspring. OBJECTIVE The objective of the project is to evaluate the risk of DNA hypomethylation due to air pollution, Mediterranean diet adherence, folate intake, and demographic and socioeconomic factors, in healthy women living in the metropolitan area of Catania, Italy. METHODS AND ANALYSIS Non-pregnant healthy women will be enrolled in a cross-sectional study. Sociodemographic, lifestyle and dietary intake information will be collected. LINE-1 methylation will be measured by pyrosequencing. The participants' home addresses will be geocoded and each woman will be assigned to the closest monitoring station for particulate matter (PM) exposure assessment. Mineralogical-chemical characterisation of PM and cellular model assays will be performed. An integrated approach will be designed to estimate the combined possible effect of air pollution, Mediterranean diet adherence, folate intake and other lifestyle characteristics on LINE-1 methylation levels. ETHICS AND DISSEMINATION The project has been approved by the ethics committees of the involved institution and funded by the University of Catania (Finanziamento della Ricerca, FIR 2014). All participants will be fully informed of the purpose and procedures of the study, and signed written consents will be obtained. All the data collected will be treated confidentially and analysed in an aggregate and anonymous way. The results will be published in peer-reviewed journals and communicated to local public health agencies, in order to provide essential information for timely and effective public health action.
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Affiliation(s)
- Martina Barchitta
- Department of Medical and Surgical Sciences and Advanced Technologies “GF Ingrassia”, University of Catania, Catania, Italy
- LaPoSS, Laboratory of Policies and Social Services, University of Catania, Catania, Italy
| | - Annalisa Quattrocchi
- Department of Medical and Surgical Sciences and Advanced Technologies “GF Ingrassia”, University of Catania, Catania, Italy
| | - Andrea Maugeri
- Department of Medical and Surgical Sciences and Advanced Technologies “GF Ingrassia”, University of Catania, Catania, Italy
| | - Germana Barone
- Department of Biological, Geological and Environmental Sciences, University of Catania, Catania, Italy
| | - Paolo Mazzoleni
- Department of Biological, Geological and Environmental Sciences, University of Catania, Catania, Italy
| | - Alfio Catalfo
- Department of Chemical Science, Section of Photochemistry and Photobiology, University of Catania, Catania, Italy
| | - Guido De Guidi
- Department of Chemical Science, Section of Photochemistry and Photobiology, University of Catania, Catania, Italy
- Research Centre for the analysis, the monitoring and methodology for environmental risk assessment (CRAM3RA), University of Catania, Catania, Italy
| | - Maria Iemmolo
- Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Nunzio Crimi
- Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Antonella Agodi
- Department of Medical and Surgical Sciences and Advanced Technologies “GF Ingrassia”, University of Catania, Catania, Italy
- LaPoSS, Laboratory of Policies and Social Services, University of Catania, Catania, Italy
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Bommarito PA, Martin E, Fry RC. Effects of prenatal exposure to endocrine disruptors and toxic metals on the fetal epigenome. Epigenomics 2017. [PMID: 28234024 DOI: 10.2217/epi-20160112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023] Open
Abstract
Exposure to environmental contaminants during pregnancy has been linked to adverse outcomes at birth and later in life. The link between prenatal exposures and latent health outcomes suggests that these exposures may result in long-term epigenetic reprogramming. Toxic metals and endocrine disruptors are two major classes of contaminants that are ubiquitously present in the environment and represent threats to human health. In this review, we present evidence that prenatal exposures to these contaminants result in fetal epigenomic changes, including altered global DNA methylation, gene-specific CpG methylation and microRNA expression. Importantly, these changes may have functional cellular consequences, impacting health outcomes later in life. Therefore, these epigenetic changes represent a critical mechanism that warrants further study.
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Affiliation(s)
- Paige A Bommarito
- Department of Environmental Sciences & Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Elizabeth Martin
- Department of Environmental Sciences & Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Rebecca C Fry
- Department of Environmental Sciences & Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Curriculum in Toxicology, University of North Carolina School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27516, USA
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35
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Bommarito PA, Martin E, Fry RC. Effects of prenatal exposure to endocrine disruptors and toxic metals on the fetal epigenome. Epigenomics 2017; 9:333-350. [PMID: 28234024 DOI: 10.2217/epi-2016-0112] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Exposure to environmental contaminants during pregnancy has been linked to adverse outcomes at birth and later in life. The link between prenatal exposures and latent health outcomes suggests that these exposures may result in long-term epigenetic reprogramming. Toxic metals and endocrine disruptors are two major classes of contaminants that are ubiquitously present in the environment and represent threats to human health. In this review, we present evidence that prenatal exposures to these contaminants result in fetal epigenomic changes, including altered global DNA methylation, gene-specific CpG methylation and microRNA expression. Importantly, these changes may have functional cellular consequences, impacting health outcomes later in life. Therefore, these epigenetic changes represent a critical mechanism that warrants further study.
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Affiliation(s)
- Paige A Bommarito
- Department of Environmental Sciences & Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Elizabeth Martin
- Department of Environmental Sciences & Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Rebecca C Fry
- Department of Environmental Sciences & Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.,Curriculum in Toxicology, University of North Carolina School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27516, USA
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36
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Vryer R, Saffery R. What's in a name? Context-dependent significance of 'global' methylation measures in human health and disease. Clin Epigenetics 2017; 9:2. [PMID: 28149330 PMCID: PMC5270354 DOI: 10.1186/s13148-017-0311-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 01/04/2017] [Indexed: 12/20/2022] Open
Abstract
The study of DNA methylation in development and disease has 'exploded' as a field in recent years, with three major classes of measurement now routine. These encompass (i) locus-specific, (ii) genome-scale/wide and (iii) 'global' methylation approaches. Measures of global methylation refer to the level of 5-methylcytosine (5mC) content in a sample relative to total cytosine. Despite this, several other measures are often referred to as 'global', with the underlying assumption that they accurately reflect 5mC content. The two most common surrogate, or proxy, measures include generating a mean or median methylation value from (i) the average measure in thousands of highly repetitive genomic elements and (ii) many thousands to several million primarily unique CpG sites throughout the genome. Numerous lines of evidence suggest the underlying assumption of equivalence of these measures is flawed, with considerable variation in the regulation of different 'flavours' of DNA methylation throughout the genome depending on cell type, differentiation and disease state. As such, the regulation of methylation 'types' is often uncoupled. The emerging picture suggests that no approach can accurately detect all biologically important differences in 5mC variation and distribution in all instances, with this needing to be ascertained on a case-by-case basis. Thus, it is important to clearly elaborate the genomic context and content of DNA methylation being analysed, the sample and developmental stage in which it is being examined and to remember that in most instances, the most common measures are not a true representation of 'global' 5mC content as orginally defined.
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Affiliation(s)
- Regan Vryer
- Murdoch Childrens Research Institute, 50 Flemington Rd, Parkville, Victoria 3052 Australia
- Department of Paediatrics, University of Melbourne, Parkville, Victoria Australia
| | - Richard Saffery
- Murdoch Childrens Research Institute, 50 Flemington Rd, Parkville, Victoria 3052 Australia
- Department of Paediatrics, University of Melbourne, Parkville, Victoria Australia
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Crary-Dooley FK, Tam ME, Dunaway KW, Hertz-Picciotto I, Schmidt RJ, LaSalle JM. A comparison of existing global DNA methylation assays to low-coverage whole-genome bisulfite sequencing for epidemiological studies. Epigenetics 2017; 12:206-214. [PMID: 28055307 PMCID: PMC5406214 DOI: 10.1080/15592294.2016.1276680] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
DNA methylation is an epigenetic mark at the interface of genetic and environmental factors relevant to human disease. Quantitative assessments of global DNA methylation levels have therefore become important tools in epidemiology research, particularly for understanding effects of environmental exposures in complex diseases. Among the available methods of quantitative DNA methylation measurements, bisulfite sequencing is considered the gold standard, but whole-genome bisulfite sequencing (WGBS) has previously been considered too costly for epidemiology studies with high sample numbers. Pyrosequencing of repetitive sequences within bisulfite-treated DNA has been routinely used as a surrogate for global DNA methylation, but a comparison of pyrosequencing to WGBS for accuracy and reproducibility of methylation levels has not been performed. This study compared the global methylation levels measured from uniquely mappable (non-repetitive) WGBS sequences to pyrosequencing assays of several repeat sequences and repeat assay-matched WGBS data and determined uniquely mappable WGBS data to be the most reproducible and accurate measurement of global DNA methylation levels. We determined sources of variation in repetitive pyrosequencing assays to be PCR amplification bias, PCR primer selection bias in methylation levels of targeted sequences, and inherent variability in methylation levels of repeat sequences. Low-coverage, uniquely mappable WGBS showed the strongest correlation between replicates of all assays. By using multiplexing by indexed bar codes, the cost of WGBS can be lowered significantly to improve the accuracy of global DNA methylation assessments for human studies.
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Affiliation(s)
- Florence K Crary-Dooley
- a Department of Medical Microbiology and Immunology , Genome Center , University of California , Davis , CA , USA
| | - Mitchell E Tam
- a Department of Medical Microbiology and Immunology , Genome Center , University of California , Davis , CA , USA
| | - Keith W Dunaway
- a Department of Medical Microbiology and Immunology , Genome Center , University of California , Davis , CA , USA
| | - Irva Hertz-Picciotto
- b Department of Public Health Sciences , University of California , Davis , CA , USA.,c MIND Institute , University of California , Davis , CA , USA
| | - Rebecca J Schmidt
- b Department of Public Health Sciences , University of California , Davis , CA , USA.,c MIND Institute , University of California , Davis , CA , USA
| | - Janine M LaSalle
- a Department of Medical Microbiology and Immunology , Genome Center , University of California , Davis , CA , USA.,c MIND Institute , University of California , Davis , CA , USA
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Vasilyev SA, Tolmacheva EN, Lebedev IN. Epigenetic regulation and role of LINE-1 retrotransposon in embryogenesis. RUSS J GENET+ 2016. [DOI: 10.1134/s1022795416120152] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Methylome analysis for spina bifida shows SOX18 hypomethylation as a risk factor with evidence for a complex (epi)genetic interplay to affect neural tube development. Clin Epigenetics 2016; 8:108. [PMID: 27757173 PMCID: PMC5064967 DOI: 10.1186/s13148-016-0272-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 09/24/2016] [Indexed: 12/21/2022] Open
Abstract
Background Neural tube defects (NTDs) are severe congenital malformations that arise from failure of neurulation during early embryonic development. The molecular basis underlying most human NTDs still remains largely unknown. Based on the hypothesis that folic acid prevents NTDs by stimulating methylation reactions, DNA methylation changes could play a role in NTDs. We performed a methylome analysis for patients with myelomeningocele (MMC). Using a candidate CpG analysis for HOX genes, a significant association between HOXB7 hypomethylation and MMC was found. Methods In the current study, we analyzed leukocyte methylome data of ten patients with MMC and six controls using Illumina Methylation Analyzer and WateRmelon R-packages and performed validation studies using larger MMC and control cohorts with Sequenom EpiTYPER. Results The methylome analysis showed 75 CpGs in 45 genes that are significantly differentially methylated in MMC patients. CpG-specific methylation differences were next replicated for the top six candidate genes ABAT, CNTNAP1, SLC1A6, SNED1, SOX18, and TEPP but only for the SOX18 locus a significant overall hypomethylation was observed (P value = 0.0003). Chemically induced DNA demethylation in HEK cells resulted in SOX18 hypomethylation and increased expression. Injection of sox18 mRNA in zebrafish resulted in abnormal neural tube formation. Quantification of DNA methylation for the SOX18 locus was also determined for five families where parents had normal methylation values compared to significant lower values for both the MMC as their non-affected child. SOX18 methylation studies were performed for a MMC patient with a paternally inherited chromosomal deletion that includes BMP4. The patient showed extreme SOX18 hypomethylation similar to his healthy mother while his father had normal methylation values. Conclusions This is the first genome-wide methylation study in leukocytes for patients with NTDs. We report SOX18 as a novel MMC risk gene but our findings also suggest that SOX18 hypomethylation must interplay with environmental and (epi)genetic factors to cause NTDs. Further studies are needed that combine methylome data with next-generation sequencing approaches to unravel NTD etiology. Electronic supplementary material The online version of this article (doi:10.1186/s13148-016-0272-8) contains supplementary material, which is available to authorized users.
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de Goede OM, Lavoie PM, Robinson WP. Characterizing the hypomethylated DNA methylation profile of nucleated red blood cells from cord blood. Epigenomics 2016; 8:1481-1494. [PMID: 27687885 DOI: 10.2217/epi-2016-0069] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
AIM To provide insight into fetal nucleated red blood cell (nRBC) development using genome-wide DNA methylation (DNAm) profiling. MATERIALS & METHODS The DNAm profile (Illumina 450K array) of cord blood (n = 7) derived nRBCs was compared with B cells, CD4 and CD8 T cells, natural killer cells, granulocytes, monocytes and placenta (n = 5). RESULTS nRBCs and placenta had similarly low array-wide DNAm compared with white blood cells, but their patterns of hypomethylation differed at biologically relevant subsets of the array. High interindividual variability in nRBC DNAm was driven by a negative association between DNAm and nRBC count. CONCLUSION nRBC hypomethylation is likely an epigenetic signature of erythropoiesis rather than of early development. Variability in nRBC DNAm may stem from differences in the cell population's maturity or hematopoietic source.
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Affiliation(s)
- Olivia M de Goede
- Child & Family Research Institute, Vancouver, British Columbia, V5Z 4H4, Canada.,Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada
| | - Pascal M Lavoie
- Child & Family Research Institute, Vancouver, British Columbia, V5Z 4H4, Canada.,Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada
| | - Wendy P Robinson
- Child & Family Research Institute, Vancouver, British Columbia, V5Z 4H4, Canada.,Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada
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Genome-wide measures of DNA methylation in peripheral blood and the risk of urothelial cell carcinoma: a prospective nested case-control study. Br J Cancer 2016; 115:664-73. [PMID: 27490804 PMCID: PMC5023776 DOI: 10.1038/bjc.2016.237] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 05/13/2016] [Accepted: 07/08/2016] [Indexed: 12/23/2022] Open
Abstract
Background: Global DNA methylation has been reported to be associated with urothelial cell carcinoma (UCC) by studies using blood samples collected at diagnosis. Using the Illumina HumanMethylation450 assay, we derived genome-wide measures of blood DNA methylation and assessed them for their prospective association with UCC risk. Methods: We used 439 case–control pairs from the Melbourne Collaborative Cohort Study matched on age, sex, country of birth, DNA sample type, and collection period. Conditional logistic regression was used to compute odds ratios (OR) of UCC risk per s.d. of each genome-wide measure of DNA methylation and 95% confidence intervals (CIs), adjusted for potential confounders. We also investigated associations by disease subtype, sex, smoking, and time since blood collection. Results: The risk of superficial UCC was decreased for individuals with higher levels of our genome-wide DNA methylation measure (OR=0.71, 95% CI: 0.54–0.94; P=0.02). This association was particularly strong for current smokers at sample collection (OR=0.47, 95% CI: 0.27–0.83). Intermediate levels of our genome-wide measure were associated with decreased risk of invasive UCC. Some variation was observed between UCC subtypes and the location and regulatory function of the CpGs included in the genome-wide measures of methylation. Conclusions: Higher levels of our genome-wide DNA methylation measure were associated with decreased risk of superficial UCC and intermediate levels were associated with reduced risk of invasive disease. These findings require replication by other prospective studies.
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Huen K, Calafat AM, Bradman A, Yousefi P, Eskenazi B, Holland N. Maternal phthalate exposure during pregnancy is associated with DNA methylation of LINE-1 and Alu repetitive elements in Mexican-American children. ENVIRONMENTAL RESEARCH 2016; 148:55-62. [PMID: 27019040 PMCID: PMC4874877 DOI: 10.1016/j.envres.2016.03.025] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 02/24/2016] [Accepted: 03/18/2016] [Indexed: 05/21/2023]
Abstract
Phthalates are frequently used in personal care products and plasticizers and phthalate exposure is ubiquitous in the US population. Exposure to phthalates during critical periods in utero has been associated with a variety of adverse health outcomes but the biological mechanisms linking these exposures with disease are not well characterized. In this study, we examined the relationship of in utero phthalate exposure with repetitive element DNA methylation, an epigenetic marker of genome instability, in children from the longitudinal birth cohort CHAMACOS. Methylation of Alu and long interspersed nucleotide elements (LINE-1) was determined using pyrosequencing of bisulfite-treated DNA isolated from whole blood samples collected from newborns and 9 year old children (n=355). Concentrations of eleven phthalate metabolites were measured in urine collected from pregnant mothers at 13 and 26 weeks gestation. We found a consistent inverse association between prenatal concentrations of monoethyl phthalate, the most frequently detected urinary metabolite, with cord blood methylation of Alu repeats (β(95%CI): -0.14 (-0.28,0.00) and -0.16 (-0.31, -0.02)) for early and late pregnancy, respectively, and a similar but weaker association with LINE-1 methylation. Additionally, increases in urinary concentrations of di-(2-ethylhexyl) phthalate metabolites during late pregnancy were associated with lower levels of methylation of Alu repeats in 9 year old blood (significant p-values ranged from 0.003 to 0.03). Our findings suggest that prenatal exposure to some phthalates may influence differences in repetitive element methylation, highlighting epigenetics as a plausible biological mechanism through which phthalates may affect health.
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Affiliation(s)
- Karen Huen
- Center for Children's Environmental Health, School of Public Health, University of California, Berkeley, 1995 University Avenue Suite 265, Berkeley, CA 94720, USA.
| | - Antonia M Calafat
- Centers for Disease Control and Prevention, 4770 Buford Hwy, MS F17, Atlanta, GA 30341, USA.
| | - Asa Bradman
- Center for Children's Environmental Health, School of Public Health, University of California, Berkeley, 1995 University Avenue Suite 265, Berkeley, CA 94720, USA.
| | - Paul Yousefi
- Center for Children's Environmental Health, School of Public Health, University of California, Berkeley, 1995 University Avenue Suite 265, Berkeley, CA 94720, USA.
| | - Brenda Eskenazi
- Center for Children's Environmental Health, School of Public Health, University of California, Berkeley, 1995 University Avenue Suite 265, Berkeley, CA 94720, USA.
| | - Nina Holland
- Center for Children's Environmental Health, School of Public Health, University of California, Berkeley, 1995 University Avenue Suite 265, Berkeley, CA 94720, USA.
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DNA methylation of LINE-1 and Alu repetitive elements in relation to sex hormones and pubertal timing in Mexican-American children. Pediatr Res 2016; 79:855-62. [PMID: 26882368 PMCID: PMC4899098 DOI: 10.1038/pr.2016.31] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 12/09/2015] [Indexed: 12/21/2022]
Abstract
BACKGROUND The molecular mechanisms linking environmental exposures to earlier pubertal development are not well characterized. Epigenetics may play an important role, but data on the relationship between epigenetic marks and puberty, particularly in humans, is limited. METHODS We used pyrosequencing to measure Alu and long interspersed nucleotide elements (LINE-1) methylation in DNA isolated from whole blood samples collected from newborns and 9-y-old children (n = 266). Tanner staging was completed six times between ages 9 and 12 y to determine pubertal status, and hormone levels were measured in 12-y-old boys. RESULTS Among girls, we observed a suggestive trend of increased odds of breast and pubic hair development with higher Alu and LINE-1 methylation in 9-y-old blood, respectively. The strongest association identified was an inverse association of LINE-1 methylation in 9-y-old girls with odds of experiencing menarche by age 12 (OR (95% CI): 0.63 (0.46, 0.87); P = 0.005). We observed a consistent inverse relationship for Alu and LINE-1 methylation at 9 y with luteinizing hormone (LH), testosterone and follicle-stimulating hormone levels in boys but it was only significant between LINE-1 and LH. CONCLUSION DNA methylation of Alu and LINE-1 may be involved in puberty initiation and development. This relationship should be confirmed in future studies.
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Consales C, Toft G, Leter G, Bonde JPE, Uccelli R, Pacchierotti F, Eleuteri P, Jönsson BAG, Giwercman A, Pedersen HS, Struciński P, Góralczyk K, Zviezdai V, Spanò M. Exposure to persistent organic pollutants and sperm DNA methylation changes in Arctic and European populations. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2016; 57:200-9. [PMID: 26801515 DOI: 10.1002/em.21994] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 12/06/2015] [Indexed: 05/28/2023]
Abstract
Persistent organic pollutants (POPs), such as PCBs (polychlorinated biphenyls) and DDT [1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane], are environmental contaminants with potential endocrine disrupting activity. DNA methylation levels in peripheral blood lymphocytes have been associated with serum concentrations of POPs in Greenland Inuit and Korean populations. Greenland Inuits are characterized by the highest worldwide POP levels. In this cross-sectional study we evaluated the relationship between serum POP concentrations and DNA methylation levels in sperm of non-occupationally exposed fertile men from Greenland, Warsaw (Poland), and Kharkiv (Ukraine). Serum levels of PCB-153 [1,2,4-trichloro-5-(2,4,5-trichlorophenyl)benzene], as a proxy of the total PCBs body burden, and of p,p'-DDE [1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene], the main metabolite of DDT were measured. Sperm DNA methylation level was assessed globally by flow cytometric (FCM) immunodetection of 5-methyl-cytosines and at specific repetitive DNA sequences (Alu, LINE-1, Satα) by PCR-pyrosequencing after bisulfite conversion. Multivariate linear regression analysis was applied to investigate correlations between serum POP concentrations and DNA methylation. No consistent associations between exposure to POPs and sperm DNA methylation at repetitive DNA sequences were detected. A statistically significant global decrease in methylation was associated with exposure to either POP by FCM analysis. This is the first study to investigate environmental exposure to POPs and DNA methylation levels considering sperm as the target cells. Although POP exposure appears to have a limited negative impact on sperm DNA methylation levels in adult males, the global hypomethylation detected by one of the methods applied suggests that further investigation is warranted.
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Affiliation(s)
- Claudia Consales
- Laboratory of Biosafety and Risk Assessment, Division of Health Technologies, Department of Sustainable Territorial and Production Systems, ENEA Casaccia Research Center, Rome, 00123, Italy
| | - Gunnar Toft
- Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus N, DK-8200, Denmark
| | - Giorgio Leter
- Laboratory of Biosafety and Risk Assessment, Division of Health Technologies, Department of Sustainable Territorial and Production Systems, ENEA Casaccia Research Center, Rome, 00123, Italy
| | - Jens Peter E Bonde
- Department of Occupational and Environmental Medicine, Bispebjerg University Hospital of Copenhagen, Copenhagen, NV, DK-2400, Denmark
| | - Raffaella Uccelli
- Laboratory of Biosafety and Risk Assessment, Division of Health Technologies, Department of Sustainable Territorial and Production Systems, ENEA Casaccia Research Center, Rome, 00123, Italy
| | - Francesca Pacchierotti
- Laboratory of Biosafety and Risk Assessment, Division of Health Technologies, Department of Sustainable Territorial and Production Systems, ENEA Casaccia Research Center, Rome, 00123, Italy
| | - Patrizia Eleuteri
- Laboratory of Biosafety and Risk Assessment, Division of Health Technologies, Department of Sustainable Territorial and Production Systems, ENEA Casaccia Research Center, Rome, 00123, Italy
| | - Bo A G Jönsson
- Division of Occupational and Environmental Medicine, Department of Laboratory Medicine, Lund University, Lund, SE-22185, Sweden
| | - Aleksander Giwercman
- Molecular Reproductive Medicine, Department of Translational Medicine, Skåne University Hospital Malmö, Lund University, Malmö, SE-20502, Sweden
| | - Henning S Pedersen
- Centre for Arctic Environmental Medicine, Greenland Institute of Natural Resources, Nuuk, Greenland, DK-3900, Denmark
| | - Paweł Struciński
- Department of Toxicology and Risk Assessment, National Institute of Public Health-National Institute of Hygiene, Warsaw, 00791, Poland
| | - Katarzyna Góralczyk
- Department of Toxicology and Risk Assessment, National Institute of Public Health-National Institute of Hygiene, Warsaw, 00791, Poland
| | - Valentyna Zviezdai
- Laboratory of Human Reproduction, Department of Social Medicine and Organization of Public Health, Kharkiv National Medical University, Kharkiv, 61022, Ukraine
| | - Marcello Spanò
- Laboratory of Biosafety and Risk Assessment, Division of Health Technologies, Department of Sustainable Territorial and Production Systems, ENEA Casaccia Research Center, Rome, 00123, Italy
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Bianco-Miotto T, Mayne BT, Buckberry S, Breen J, Rodriguez Lopez CM, Roberts CT. Recent progress towards understanding the role of DNA methylation in human placental development. Reproduction 2016; 152:R23-30. [PMID: 27026712 PMCID: PMC5064761 DOI: 10.1530/rep-16-0014] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Accepted: 03/29/2016] [Indexed: 12/20/2022]
Abstract
Epigenetic modifications, and particularly DNA methylation, have been studied in many tissues, both healthy and diseased, and across numerous developmental stages. The placenta is the only organ that has a transient life of 9 months and undergoes rapid growth and dynamic structural and functional changes across gestation. Additionally, the placenta is unique because although developing within the mother, its genome is identical to that of the foetus. Given these distinctive characteristics, it is not surprising that the epigenetic landscape affecting placental gene expression may be different to that in other healthy tissues. However, the role of epigenetic modifications, and particularly DNA methylation, in placental development remains largely unknown. Of particular interest is the fact that the placenta is the most hypomethylated human tissue and is characterized by the presence of large partially methylated domains (PMDs) containing silenced genes. Moreover, how and why the placenta is hypomethylated and what role DNA methylation plays in regulating placental gene expression across gestation are poorly understood. We review genome-wide DNA methylation studies in the human placenta and highlight that the different cell types that make up the placenta have very different DNA methylation profiles. Summarizing studies on DNA methylation in the placenta and its relationship with pregnancy complications are difficult due to the limited number of studies available for comparison. To understand the key steps in placental development and hence what may be perturbed in pregnancy complications requires large-scale genome-wide DNA methylation studies coupled with transcriptome analyses.
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Affiliation(s)
- Tina Bianco-Miotto
- School of Agriculture, Food and WineUniversity of Adelaide, Adelaide, South Australia, Australia Robinson Research InstituteUniversity of Adelaide, Adelaide, South Australia, Australia
| | - Benjamin T Mayne
- Robinson Research InstituteUniversity of Adelaide, Adelaide, South Australia, Australia School of MedicineUniversity of Adelaide, Adelaide, South Australia, Australia
| | - Sam Buckberry
- Harry Perkins Institute of Medical ResearchThe University of Western Australia, Crawley, Western Australia, Australia Plant Energy BiologyARC Centre of Excellence, The University of Western Australia, Crawley, Western Australia, Australia
| | - James Breen
- Robinson Research InstituteUniversity of Adelaide, Adelaide, South Australia, Australia Bioinformatics HubUniversity of Adelaide, Adelaide, South Australia, Australia
| | - Carlos M Rodriguez Lopez
- School of Agriculture, Food and WineUniversity of Adelaide, Adelaide, South Australia, Australia
| | - Claire T Roberts
- Robinson Research InstituteUniversity of Adelaide, Adelaide, South Australia, Australia School of MedicineUniversity of Adelaide, Adelaide, South Australia, Australia
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Hanna CW, Peñaherrera MS, Saadeh H, Andrews S, McFadden DE, Kelsey G, Robinson WP. Pervasive polymorphic imprinted methylation in the human placenta. Genome Res 2016; 26:756-67. [PMID: 26769960 PMCID: PMC4889973 DOI: 10.1101/gr.196139.115] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 01/07/2016] [Indexed: 01/19/2023]
Abstract
The maternal and paternal copies of the genome are both required for mammalian development, and this is primarily due to imprinted genes, those that are monoallelically expressed based on parent-of-origin. Typically, this pattern of expression is regulated by differentially methylated regions (DMRs) that are established in the germline and maintained after fertilization. There are a large number of germline DMRs that have not yet been associated with imprinting, and their function in development is unknown. In this study, we developed a genome-wide approach to identify novel imprinted DMRs in the human placenta and investigated the dynamics of these imprinted DMRs during development in somatic and extraembryonic tissues. DNA methylation was evaluated using the Illumina HumanMethylation450 array in 134 human tissue samples, publicly available reduced representation bisulfite sequencing in the human embryo and germ cells, and targeted bisulfite sequencing in term placentas. Forty-three known and 101 novel imprinted DMRs were identified in the human placenta by comparing methylation between diandric and digynic triploid conceptions in addition to female and male gametes. Seventy-two novel DMRs showed a pattern consistent with placental-specific imprinting, and this monoallelic methylation was entirely maternal in origin. Strikingly, these DMRs exhibited polymorphic imprinted methylation between placental samples. These data suggest that imprinting in human development is far more extensive and dynamic than previously reported and that the placenta preferentially maintains maternal germline-derived DNA methylation.
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Affiliation(s)
- Courtney W Hanna
- Epigenetics Programme, Babraham Institute, Cambridge CB22 3AT, United Kingdom; Centre for Trophoblast Research, University of Cambridge, Cambridge CB2 3EG, United Kingdom
| | - Maria S Peñaherrera
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia V6H 3N1, Canada; Child & Family Research Institute, Vancouver, British Columbia V5Z 4H4, Canada
| | - Heba Saadeh
- Epigenetics Programme, Babraham Institute, Cambridge CB22 3AT, United Kingdom; Bioinformatics Group, Babraham Institute, Cambridge CB22 3AT, United Kingdom
| | - Simon Andrews
- Bioinformatics Group, Babraham Institute, Cambridge CB22 3AT, United Kingdom
| | - Deborah E McFadden
- Department of Pathology, University of British Columbia, Vancouver, British Columbia V6T 2B5, Canada
| | - Gavin Kelsey
- Epigenetics Programme, Babraham Institute, Cambridge CB22 3AT, United Kingdom; Centre for Trophoblast Research, University of Cambridge, Cambridge CB2 3EG, United Kingdom
| | - Wendy P Robinson
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia V6H 3N1, Canada; Child & Family Research Institute, Vancouver, British Columbia V5Z 4H4, Canada
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Environmental Impact on DNA Methylation in the Germline: State of the Art and Gaps of Knowledge. BIOMED RESEARCH INTERNATIONAL 2015; 2015:123484. [PMID: 26339587 PMCID: PMC4538313 DOI: 10.1155/2015/123484] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 05/03/2015] [Indexed: 12/19/2022]
Abstract
The epigenome consists of chemical changes in DNA and chromatin that without modifying the DNA sequence modulate gene expression and cellular phenotype. The epigenome is highly plastic and reacts to changing external conditions with modifications that can be inherited to daughter cells and across generations. Whereas this innate plasticity allows for adaptation to a changing environment, it also implies the potential of epigenetic derailment leading to so-called epimutations. DNA methylation is the most studied epigenetic mark. DNA methylation changes have been associated with cancer, infertility, cardiovascular, respiratory, metabolic, immunologic, and neurodegenerative pathologies. Experiments in rodents demonstrate that exposure to a variety of chemical stressors, occurring during the prenatal or the adult life, may induce DNA methylation changes in germ cells, which may be transmitted across generations with phenotypic consequences. An increasing number of human biomonitoring studies show environmentally related DNA methylation changes mainly in blood leukocytes, whereas very few data have been so far collected on possible epigenetic changes induced in the germline, even by the analysis of easily accessible sperm. In this paper, we review the state of the art on factors impinging on DNA methylation in the germline, highlight gaps of knowledge, and propose priorities for future studies.
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Nahar MS, Liao C, Kannan K, Harris C, Dolinoy DC. In utero bisphenol A concentration, metabolism, and global DNA methylation across matched placenta, kidney, and liver in the human fetus. CHEMOSPHERE 2015; 124:54-60. [PMID: 25434263 PMCID: PMC4297568 DOI: 10.1016/j.chemosphere.2014.10.071] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 10/28/2014] [Accepted: 10/31/2014] [Indexed: 05/18/2023]
Abstract
While urine has been an easily accessible and feasible matrix for human biomonitoring, analytical measurements in internal tissues and organs can provide more accurate exposure assessments to understand disease etiology. This is especially important for the endocrine active compound, bisphenol A (BPA), where studies investigating internal doses at sensitive periods of human development are currently lacking. Herein, BPA concentrations, BPA-specific metabolizing enzyme gene expression, and global DNA methylation were characterized across three matched tissues from elective pregnancy terminations of 2nd trimester human fetuses: the placenta, liver, and kidney (N=12 each; N=36 total). Compared to liver (free: 0.54-50.5 ng g(-1)), BPA concentrations were lower in matched placenta (<0.05-25.4 ng g(-1)) and kidney (0.08-11.1 ng g(-1)) specimens. BPA-specific metabolism gene expression of GUSB, UGT2B15, STS, and SULT1A1 differed across each tissue type; however, conjugation and deconjugation expression patterns were similar across the fetus. Average LINE1 and CCGG global methylation were 58.3% and 59.2% in placenta, 79.5% and 66.4% in fetal liver, and 77.9% and 77.0% in fetal kidney, with significant tissue-specific DNA methylation differences in both LINE1 (p-value<0.001) and CCGG content (p-value<0.001). Total BPA concentrations were positively associated with global methylation for the placenta only using the LINE1 assay (p-value: 0.002), suggesting organ-specific biological effects after fetal exposure. Utilizing sensitive human clinical specimens, results are informative for BPA toxicokinetics and toxicodynamics assessment in the developing human fetus.
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Affiliation(s)
- Muna S Nahar
- Department of Environmental Health Sciences, University of Michigan, Ann Arbor, MI, USA
| | - Chunyang Liao
- Wadsworth Center, New York State Department of Health, Department of Environmental Health Sciences, State University of New York at Albany, Albany, NY, USA
| | - Kurunthachalam Kannan
- Wadsworth Center, New York State Department of Health, Department of Environmental Health Sciences, State University of New York at Albany, Albany, NY, USA; Experimental Biochemistry Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Craig Harris
- Department of Environmental Health Sciences, University of Michigan, Ann Arbor, MI, USA
| | - Dana C Dolinoy
- Department of Environmental Health Sciences, University of Michigan, Ann Arbor, MI, USA.
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Abstract
This review provides an overview of the unique features of DNA methylation in the human placenta. We discuss the importance of understanding placental development, structure, and function in the interpretation of DNA methylation data. Examples are given of how DNA methylation is important in regulating placental-specific gene expression, including monoallelic expression and X-chromosome inactivation in the placenta. We also discuss studies of global DNA methylation changes in the context of placental pathology and environmental exposures.
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Affiliation(s)
- Wendy P Robinson
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada Child & Family Research Institute, Vancouver, British Columbia V5Z 4H4, Canada
| | - E Magda Price
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada Child & Family Research Institute, Vancouver, British Columbia V5Z 4H4, Canada
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Vasilyev SA, Tolmacheva EN, Kashevarova AA, Sazhenova EA, Lebedev IN. Methylation status of LINE-1 retrotransposon in chromosomal mosaicism during early stages of human embryonic development. Mol Biol 2015. [DOI: 10.1134/s0026893314060193] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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