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Lipids in Health and Disease Oct 2019Chronic illnesses like obesity, type 2 diabetes (T2D) and cardiovascular diseases, are worldwide major causes of morbidity and mortality. These pathological conditions...
BACKGROUND
Chronic illnesses like obesity, type 2 diabetes (T2D) and cardiovascular diseases, are worldwide major causes of morbidity and mortality. These pathological conditions involve interactions between environmental, genetic, and epigenetic factors. Recent advances in nutriepigenomics are contributing to clarify the role of some nutritional factors, including dietary fatty acids in gene expression regulation. This systematic review assesses currently available information concerning the role of the different fatty acids on epigenetic mechanisms that affect the development of chronic diseases or induce protective effects on metabolic alterations.
METHODS
A targeted search was conducted in the PubMed/Medline databases using the keywords "fatty acids and epigenetic". The data were analyzed according to the PRISMA-P guidelines.
RESULTS
Consumption fatty acids like n-3 PUFA: EPA and DHA, and MUFA: oleic and palmitoleic acid was associated with an improvement of metabolic alterations. On the other hand, fatty acids that have been associated with the presence or development of obesity, T2D, pro-inflammatory profile, atherosclerosis and IR were n-6 PUFA, saturated fatty acids (stearic and palmitic), and trans fatty acids (elaidic), have been also linked with epigenetic changes.
CONCLUSIONS
Fatty acids can regulate gene expression by modifying epigenetic mechanisms and consequently result in positive or negative impacts on metabolic outcomes.
Topics: Animals; Cardiovascular Diseases; Chronic Disease; DNA Methylation; Diabetes Mellitus, Type 2; Dietary Fats; Disease Models, Animal; Epigenesis, Genetic; Fatty Acids; Fatty Acids, Omega-3; Fatty Acids, Omega-6; Gene-Environment Interaction; Humans; Insulin Resistance; Lipid Metabolism; Obesity; Trans Fatty Acids
PubMed: 31615571
DOI: 10.1186/s12944-019-1120-6 -
Journal of Affective Disorders Apr 2023Growing evidence suggests that epigenetic modification is vital in biological processes of depression. Findings from studies exploring the associations between DNA... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Growing evidence suggests that epigenetic modification is vital in biological processes of depression. Findings from studies exploring the associations between DNA methylation and depression have been inconsistent.
METHODS
A systematical search of EMBASE, PubMed, Web of Science, and PsycINFO databases was conducted to include studies focusing on the associations between DNA methylation and depression (up to November 1st 2021) according to PRISMA guidelines with registration in PROSPERO (CRD42021288664).
RESULTS
A total of 47 studies met inclusion criteria and 31 studies were included in the meta-analysis. This meta-analysis found that genes hypermethylation, including BDNF (OR: 1.15, 95%CI: 1.01-1.32, I = 90 %), and NR3C1 (OR: 1.43, 95%CI: 1.09-1.87, I = 88 %) was associated with increased risk of depression. Significant association of SLC6A4 hypermethylation with depression was only found in the subgroup of using original data (OR: 1.09, 95%CI: 1.01-1.19, I = 52 %). BDNF hypermethylation could increase the risk of depression only in the Asian population (OR: 1.18, 95%CI: 1.01-1.40, I = 91 %), and significant associations of NR3C1 hypermethylation with depression were found in the group for depressive symptoms (OR: 1.34, 95%CI: 1.08-1.67, I = 85 %), but not for depressive disorder (OR: 1.89, 95%CI: 0.54-6.55, I = 94 %).
LIMITATIONS
More studies are needed to explore the factors that might influence the estimates owing to the contextual heterogeneity of the pooling of included studies.
CONCLUSIONS
It is noted that DNA hypermethylation, namely BDNF and NR3C1, is associated with increased risk of depression. The findings in this study could provide some material evidence for preventing and diagnosing of depression.
Topics: Humans; Brain-Derived Neurotrophic Factor; Depression; DNA Methylation; Epigenesis, Genetic; Serotonin Plasma Membrane Transport Proteins
PubMed: 36717033
DOI: 10.1016/j.jad.2023.01.079 -
International Journal of Molecular... Apr 2023This systematic review and meta-analysis summarize the difference in the methylation of the gene in patients with abnormal versus normal conventional sperm parameters.... (Meta-Analysis)
Meta-Analysis Review
This systematic review and meta-analysis summarize the difference in the methylation of the gene in patients with abnormal versus normal conventional sperm parameters. It also evaluates the effects of age and sperm concentration on methylation in spermatozoa using meta-regression analysis. It was performed according to the MOOSE guidelines for meta-analyses and Systematic Reviews of Observational Studies and the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P). The quality of the evidence reported in the studies included was assessed using the Cambridge Quality Checklists. A total of 11 articles met our inclusion criteria. Quantitative analysis showed that methylation levels were significantly lower in the group of infertile patients than in fertile controls. The reduction in methylation was much more pronounced in patients with oligozoospermia (alone or associated with other sperm parameter abnormalities) and in those with recurrent pregnancy loss. Meta-regression analysis showed the results to be independent of both patient age and sperm concentration. Therefore, the methylation pattern should be evaluated among couples accessing assisted reproductive techniques (ART), in order to gain prognostic information on ART outcome and offspring health.
Topics: Female; Humans; Male; Pregnancy; DNA Methylation; Genomic Imprinting; Histones; Infertility, Male; Meta-Analysis as Topic; Semen; Spermatozoa
PubMed: 37108386
DOI: 10.3390/ijms24087224 -
International Journal of Obesity (2005) Jan 2015Recent technological advances in epigenome profiling have led to an increasing number of studies investigating the role of the epigenome in obesity. There is also... (Review)
Review
BACKGROUND
Recent technological advances in epigenome profiling have led to an increasing number of studies investigating the role of the epigenome in obesity. There is also evidence that environmental exposures during early life can induce persistent alterations in the epigenome, which may lead to an increased risk of obesity later in life.
METHOD
This paper provides a systematic review of studies investigating the association between obesity and either global, site-specific or genome-wide methylation of DNA. Studies on the impact of pre- and postnatal interventions on methylation and obesity are also reviewed. We discuss outstanding questions, and introduce EpiSCOPE, a multidisciplinary research program aimed at increasing the understanding of epigenetic changes in emergence of obesity.
RESULTS
An electronic search for relevant articles, published between September 2008 and September 2013 was performed. From the 319 articles identified, 46 studies were included and reviewed. The studies provided no consistent evidence for a relationship between global methylation and obesity. The studies did identify multiple obesity-associated differentially methylated sites, mainly in blood cells. Extensive, but small, alterations in methylation at specific sites were observed in weight loss intervention studies, and several associations between methylation marks at birth and later life obesity were found.
CONCLUSIONS
Overall, significant progress has been made in the field of epigenetics and obesity and the first potential epigenetic markers for obesity that could be detected at birth have been identified. Eventually this may help in predicting an individual's obesity risk at a young age and opens possibilities for introducing targeted prevention strategies. It has also become clear that several epigenetic marks are modifiable, by changing the exposure in utero, but also by lifestyle changes in adult life, which implies that there is the potential for interventions to be introduced in postnatal life to modify unfavourable epigenomic profiles.
Topics: Cardiovascular Diseases; Cross-Sectional Studies; DNA Methylation; Diabetes Mellitus, Type 2; Environmental Exposure; Epigenomics; Global Health; Humans; Life Style; Longitudinal Studies; Obesity; Weight Loss
PubMed: 24566855
DOI: 10.1038/ijo.2014.34 -
Psychiatry Research Jan 2022Schizophrenia has a large disease burden globally. Early intervention in psychosis, and therefore a decreased duration of untreated psychosis, has a positive clinical... (Review)
Review
BACKGROUND
Schizophrenia has a large disease burden globally. Early intervention in psychosis, and therefore a decreased duration of untreated psychosis, has a positive clinical impact. There are several recognized risk factors for psychosis, including trauma history and substance use. This systematic review examined the literature for studies related to epigenetic changes in first-episode psychosis, with the goal of identifying future research directions.
METHODS
A literature review was conducted from inception to October 3, 2021 using MedLine/PubMed, Web of Science, and PsycInfo searches with the keywords ("first-episode schizophrenia" OR "first-episode psychosis" OR "drug-naive schizophrenia" OR "drug-naive psychosis") AND (epigenetic OR methylation OR hydroxymethylation OR "histone modification" OR "miRNA") as well as a search of the bibliography of the identified papers.
RESULTS
Seventeen studies that examined various portions of the genome were included in this systematic review. There were two studies that showed hypomethylation at the LINE-1 portion of the genome and two that showed hypermethylation at LINE-1. Additionally, two studies showed hypomethylation specifically at the GRIN2B promoter (part of LINE-1).
CONCLUSIONS
Although sample sizes were small, these studies provide evidence for epigenetic alterations in early psychosis. Further research in this area is warranted for more definitive epigenetic correlations.
Topics: DNA Methylation; Epigenesis, Genetic; Humans; Promoter Regions, Genetic; Psychotic Disorders; Schizophrenia
PubMed: 34896847
DOI: 10.1016/j.psychres.2021.114325 -
Neuroscience and Biobehavioral Reviews Apr 2023Child maltreatment (CM) encompasses sexual abuse, physical abuse, emotional abuse, neglect, and exposure to domestic and family violence. Epigenetic research... (Review)
Review
Child maltreatment (CM) encompasses sexual abuse, physical abuse, emotional abuse, neglect, and exposure to domestic and family violence. Epigenetic research investigating CM has focused on differential DNA methylation (DNAm) in genes associated with the stress response, but there has been limited evaluation of the specific effects of subtypes of CM. This systematic review of literature investigating DNAm associated with CM in non-clinical populations aimed to summarise the approaches currently used in research, how the type of maltreatment and age of exposure were encoded via methylation, and which genes have consistently been associated with CM. A total of fifty-four papers were eligible for review, including forty-one candidate gene studies, eight epigenome-wide association studies, and five studies with a mixed design. The ways in which the various forms of CM were conceptualised and measured varied between papers. Future studies would benefit from assessments that employ conceptually robust definitions of CM, and that capture important contextual information such as age of exposure and subtype of CM.
Topics: Child; Humans; DNA Methylation; Child Abuse
PubMed: 36764637
DOI: 10.1016/j.neubiorev.2023.105079 -
Journal of Nippon Medical School =... 2018Epigenetic inactivation of tumor suppressor genes is an important molecular mechanism in the formation and development of human tumors. The purpose of our study was to... (Review)
Review
BACKGROUND/AIM
Epigenetic inactivation of tumor suppressor genes is an important molecular mechanism in the formation and development of human tumors. The purpose of our study was to evaluate the correlation between the methylation level of the secreted frizzled-related protein 1 (SFRP1) gene and the risk of renal cell carcinoma (RCC).
METHODS
The relevant literature was searched in detail in several electronic databases. The methodological heterogeneity was analyzed by meta-regression and subgroup analyses. The odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were calculated to summarize the dichotomous outcomes of our meta-analysis.
RESULTS
The ten included articles contained 535 RCC samples and 475 normal controls. The results demonstrated that the methylation level of the SFRP1 promoter region was significantly correlated with an increased incidence of RCC (OR=13.72; 95% CI: 6.01-31.28; P=0.000). Furthermore, the eligible studies that had sufficient clinical data about the RCC cases were included in the analysis, and the results indicated that the frequency of SFRP1 promoter methylation was associated with a higher histological grade (P=0.000), tumor stage (P=0.033), tumor size (≥5 cm; P=0.029), and distant metastasis (P=0.047).
CONCLUSION
Our results indicate that the methylation level of the SFRP1 promoter region is increased in patients with RCC compared to normal controls and might be involved in the occurrence and development of RCC. Additional well-designed studies are needed to further verify our conclusions.
Topics: Carcinoma, Renal Cell; Confidence Intervals; Humans; Incidence; Intercellular Signaling Peptides and Proteins; Kidney Neoplasms; Membrane Proteins; Meta-Analysis as Topic; Methylation; Neoplasm Metastasis; Neoplasm Staging; Odds Ratio; Promoter Regions, Genetic; Risk
PubMed: 29731501
DOI: 10.1272/jnms.2018_85-13 -
Current Stem Cell Research & Therapy 2018Development is an epigenetic regulation dependent event. As one pretranscriptional regulator, bivalent histone modifications were observed to be involved in development... (Review)
Review
BACKGROUND
Development is an epigenetic regulation dependent event. As one pretranscriptional regulator, bivalent histone modifications were observed to be involved in development recently. It is believed that histone methylation potentially takes charge of cell fate determination and differentiation. The synchronous existence of functionally opposite histone marks at transcript start sequence (TSS) is defined as "Bivalency", which mainly mark development related genes. H3K4me3 and H3K27me3, the prominent histone methylations of bivalency, are implicated in transcriptional activation and transcriptional repression respectively. The delicate balance between H3K4me3 and H3K27me3 produces diverse chromatin architectures, resulting in different transcription states of downstream genes: "poised", "activated" or "repressed".
OBJECTIVE
In order to explore the developmental role of bivalent histone modification and the underlying mechanism, we did systematic review and rigorous assessment about relative literatures.
RESULT
Bivalent histone modifications are considered to set up genes for activation during lineage commitment by H3K4me3 and repress lineage control genes to maintain pluripotency by H3K27me3. Summarily, bivalency in stem cells keeps stemness via poising differentiation relevant genes. After receiving developmental signals, the balance between "gene activation" and "gene repression" is broken, which turns genes transcription state from "poised" effect to switch on or switch off effect, thus initiates irreversible and spontaneous differentiation procedures.
CONCLUSION
Bivalent histone modifications and the associated histone-modifying complexes safeguard proper and robust differentiation of stem cells, thus playing an essential role in development.
Topics: Animals; Cell Differentiation; Chromatin; Embryonic Stem Cells; Epigenesis, Genetic; Gene Expression Regulation, Developmental; Histones; Humans
PubMed: 28117006
DOI: 10.2174/1574888X12666170123144743 -
EBioMedicine May 2024This study investigates the associations between air pollution and colorectal cancer (CRC) risk and survival from an epigenomic perspective. (Meta-Analysis)
Meta-Analysis
BACKGROUND
This study investigates the associations between air pollution and colorectal cancer (CRC) risk and survival from an epigenomic perspective.
METHODS
Using a newly developed Air Pollutants Exposure Score (APES), we utilized a prospective cohort study (UK Biobank) to investigate the associations of individual and combined air pollution exposures with CRC incidence and survival, followed by an up-to-date systematic review with meta-analysis to verify the associations. In epigenetic two-sample Mendelian randomization analyses, we examine the associations between genetically predicted DNA methylation related to air pollution and CRC risk. Further genetic colocalization and gene-environment interaction analyses provided different insights to disentangle pathogenic effects of air pollution via epigenetic modification.
FINDINGS
During a median 12.97-year follow-up, 5767 incident CRC cases among 428,632 participants free of baseline CRC and 533 deaths in 2401 patients with CRC were documented in the UK Biobank. A higher APES score was associated with an increased CRC risk (HR, 1.03, 95% CI = 1.01-1.06; P = 0.016) and poorer survival (HR, 1.13, 95% CI = 1.03-1.23; P = 0.010), particularly among participants with insufficient physical activity and ever smokers (P > 0.05). A subsequent meta-analysis of seven observational studies, including UK Biobank data, corroborated the association between PM exposure (per 10 μg/m increment) and elevated CRC risk (RR,1.42, 95% CI = 1.12-1.79; P = 0.004; I = 90.8%). Genetically predicted methylation at PM-related CpG site cg13835894 near TMBIM1/PNKD and cg16235962 near CXCR5, and NO-related cg16947394 near TMEM110 were associated with an increased CRC risk. Gene-environment interaction analysis confirmed the epigenetic modification of aforementioned CpG sites with CRC risk and survival.
INTERPRETATION
Our study suggests the association between air pollution and CRC incidence and survival, underscoring the possible modifying roles of epigenomic factors. Methylation may partly mediate pathogenic effects of air pollution on CRC, with annotation to epigenetic alterations in protein-coding genes TMBIM1/PNKD, CXCR5 and TMEM110.
FUNDING
Xue Li is supported by the Natural Science Fund for Distinguished Young Scholars of Zhejiang Province (LR22H260001), the National Nature Science Foundation of China (No. 82204019) and Healthy Zhejiang One Million People Cohort (K-20230085). ET is supported by a Cancer Research UK Career Development Fellowship (C31250/A22804). MGD is supported by the MRC Human Genetics Unit Centre Grant (U127527198).
Topics: Aged; Female; Humans; Male; Middle Aged; Air Pollutants; Air Pollution; Colorectal Neoplasms; DNA Methylation; Environmental Exposure; Epigenesis, Genetic; Epigenomics; Gene-Environment Interaction; Incidence; Mendelian Randomization Analysis; Prospective Studies; Risk Factors
PubMed: 38631091
DOI: 10.1016/j.ebiom.2024.105126 -
Ageing Research Reviews Nov 2022Modifications of RNA, collectively called the "epitranscriptome", might provide novel biomarkers and innovative targets for interventions in geroscience but are just... (Review)
Review
Modifications of RNA, collectively called the "epitranscriptome", might provide novel biomarkers and innovative targets for interventions in geroscience but are just beginning to be studied in the context of ageing and stress resistance. RNA modifications modulate gene expression by affecting translation initiation and speed, miRNA binding, RNA stability, and RNA degradation. Nonetheless, the precise underlying molecular mechanisms and physiological consequences of most alterations of the epitranscriptome are still only poorly understood. We here systematically review different types of modifications of rRNA, tRNA and mRNA, the methodology to analyze them, current challenges in the field, and human disease associations. Furthermore, we compiled evidence for a connection between individual enzymes, which install RNA modifications, and lifespan in yeast, worm and fly. We also included resistance to different stressors and competitive fitness as search criteria for genes potentially relevant to ageing. Promising candidates identified by this approach include RCM1/NSUN5, RRP8, and F33A8.4/ZCCHC4 that introduce base methylations in rRNA, the methyltransferases DNMT2 and TRM9/ALKBH8, as well as factors involved in the thiolation or A to I editing in tRNA, and finally the mA machinery for mRNA.
Topics: Aging; AlkB Homolog 8, tRNA Methyltransferase; Animals; Humans; Methyltransferases; MicroRNAs; RNA, Messenger; RNA, Ribosomal; RNA, Transfer; Saccharomyces cerevisiae
PubMed: 35908668
DOI: 10.1016/j.arr.2022.101700