150 results on '"Philibert RA"'
Search Results
2. Methylation at 5HTT mediates the impact of child sex abuse on women's antisocial behavior: an examination of the Iowa adoptee sample.
- Author
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Beach SR, Brody GH, Todorov AA, Gunter TD, Philibert RA, Beach, Steven R H, Brody, Gene H, Todorov, Alexandre A, Gunter, Tracy D, and Philibert, Robert A
- Published
- 2011
- Full Text
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3. Interplay of genes and early mother-child relationship in the development of self-regulation from toddler to preschool age.
- Author
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Kochanska G, Philibert RA, and Barry RA
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- 2009
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4. Prevention Effects Moderate the Association of 5-HTTLPR and Youth Risk Behavior Initiation: Gene x Environment Hypotheses Tested via a Randomized Prevention Design.
- Author
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Brody GH, Beach SR, Philibert RA, Chen YF, and Murry VM
- Published
- 2009
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5. G x E interaction in the organization of attachment: mothers' responsiveness as a moderator of children's genotypes.
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Barry RA, Kochanska G, and Philibert RA
- Published
- 2008
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6. Epigenetic and Proteomic Biomarkers of Elevated Alcohol Use Predict Epigenetic Aging and Cell-Type variation Better Than Self-Report.
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Beach SRH, Ong ML, Gibbons FX, Gerrard M, Lei MK, Dawes K, and Philibert RA
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- Adult, Humans, Self Report, Alcohol Drinking genetics, Biomarkers, Aging genetics, Epigenesis, Genetic, Carbohydrates, Proteomics, Cotinine
- Abstract
Excessive alcohol consumption (EAC) has a generally accepted effect on morbidity and mortality, outcomes thought to be reflected in measures of epigenetic aging (EA). As the association of self-reported EAC with EA has not been consistent with these expectations, underscoring the need for readily employable non-self-report tools for accurately assessing and monitoring the contribution of EAC to accelerated EA, newly developed alcohol consumption DNA methylation indices, such as the Alcohol T Score (ATS) and Methyl DetectR (MDR), may be helpful. To test that hypothesis, we used these new indices along with the carbohydrate deficient transferrin (CDT), concurrent as well as past self-reports of EAC, and well-established measures of cigarette smoking to examine the relationship of EAC to both accelerated EA and immune cell counts in a cohort of 437 young Black American adults. We found that MDR, CDT, and ATS were intercorrelated, even after controlling for gender and cotinine effects. Correlations between EA and self-reported EAC were low or non-significant, replicating prior research, whereas correlations with non-self-report indices were significant and more substantial. Comparing non-self-report indices showed that the ATS predicted more than four times as much variance in EA, CDT4 cells and B-cells as for both the MDR and CDT, and better predicted indices of accelerated EA. We conclude that each of the non-self-report indices have differing predictive capacities with respect to key alcohol-related health outcomes, and that the ATS may be particularly useful for clinicians seeking to understand and prevent accelerated EA. The results also underscore the likelihood of substantial underestimates of problematic use when self-report is used and a reduction in correlations with EA and variance in cell-types.
- Published
- 2022
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7. Do Loneliness and Per Capita Income Combine to Increase the Pace of Biological Aging for Black Adults across Late Middle Age?
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Beach SRH, Klopack ET, Carter SE, Philibert RA, Simons RL, Gibbons FX, Ong ML, Gerrard M, and Lei MK
- Subjects
- Adult, Middle Aged, Humans, Aging, Black People, DNA, Loneliness, Income
- Abstract
In a sample of 685 late middle-aged Black adults (M age at 2019 = 57.17 years), we examined the effects of loneliness and per capita income on accelerated aging using a newly developed DNA-methylation based index: the DunedinPACE. First, using linear, mixed effects regression in a growth curve framework, we found that change in DunedinPACE was dependent on age, with a linear model best fitting the data (b = 0.004, p < 0.001), indicating that average pace of change increased among older participants. A quadratic effect was also tested, but was non-significant. Beyond the effect of age, both change in loneliness (b = 0.009, p < 0.05) and change in per capita income (b = -0.016, p < 0.001) were significantly associated with change in DunedinPACE across an 11-year period, accounting for significant between person variability observed in the unconditional model. Including non-self-report indices of smoking and alcohol use did not reduce the association of loneliness or per capita income with DunedinPACE. However, change in smoking was strongly associated with change in DunedinPACE such that those reducing their smoking aged less rapidly than those continuing to smoke. In addition, both loneliness and per capita income were associated with DunedinPACE after controlling for variation in cell-types.
- Published
- 2022
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8. Methylation of FKBP5 is associated with accelerated DNA methylation ageing and cardiometabolic risk: replication in young-adult and middle-aged Black Americans.
- Author
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Beach SRH, Ong ML, Lei MK, Carter SE, Simons RL, Gibbons FX, and Philibert RA
- Subjects
- Adult, Aging genetics, Body Mass Index, Glycated Hemoglobin genetics, Humans, Middle Aged, Tacrolimus Binding Proteins genetics, Tacrolimus Binding Proteins metabolism, Young Adult, Cardiovascular Diseases genetics, DNA Methylation
- Abstract
Methylation of FKBP5 is involved in the regulation of the stress response and is influenced by early stress exposure. Two CpG sites, cg20813374 and cg00130530, have been identified as potential reporters of early stress. We examined whether FKBP5 methylation was associated with accelerated DNA methylation ageing and indirectly predicted poorer cardiovascular health among both young adult and middle-aged Black Americans. Four hundred and forty-nine young adults, with a mean age of 28.67 and N = 469 middle-age parents and their current partners with a mean age of 57.21, provided self-reports, biometric assessments, and blood draws. Methylation values were obtained using the Illumina Epic Array. Cardiometabolic risk was calculated by summing the standardized log-transformed scores for the body mass index, mean arterial blood pressure, and HbA1c. We also used a more standard index of risk, the Framingham 10-year cardiometabolic risk index, as an alternative measure of cardiometabolic risk. To measure accelerated ageing, four widely used indices of accelerated, DNA methylation-based ageing were used controlling sex, age, other variation in FKBP5, and cell-type. Exposure to community danger was associated with demethylation of FKBP5. FKBP5 methylation was significantly associated with accelerated ageing for both young-adult and middle-aged samples, with significant indirect effects from FKBP5 methylation to cardiometabolic risk through accelerated ageing for both. Early exposure to danger may influence FKBP5 methylation. In turn, FKBP5 methylation may help explain intrinsic accelerated ageing and elevated cardiometabolic risk in adulthood for Black Americans.
- Published
- 2022
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9. Childhood adversity predicts black young adults' DNA methylation-based accelerated aging: A dual pathway model.
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Beach SRH, Gibbons FX, Carter SE, Ong ML, Lavner JA, Lei MK, Simons RL, Gerrard M, and Philibert RA
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- Animals, Humans, Young Adult, Child, Adolescent, Adult, Hylobates genetics, Aging genetics, DNA, Epigenesis, Genetic, DNA Methylation, Adverse Childhood Experiences
- Abstract
We expand upon prior work (Gibbons et al., ) relating childhood stressor effects, particularly harsh childhood environments, to risky behavior and ultimately physical health by adding longer-term outcomes - deoxyribonucleic acid (DNA) methylation-based measures of accelerated aging (DNA
m -aging). Further, following work on the effects of early exposure to danger (McLaughlin et al., ), we also identify an additional pathway from harsh childhood environments to DNAm -aging that we label the danger/FKBP5 pathway, which includes early exposure to dangerous community conditions that are thought to impact glucocorticoid regulation and pro-inflammatory mechanisms. Because different DNAm -aging indices provide different windows on accelerated aging, we contrast effects on early indices of DNAm -aging based on chronological age with later indices that focused on predicting biological outcomes. We utilize data from Family and Community Health Study participants ( N = 449) from age 10 to 29. We find that harshness influences parenting, which, in turn, influences accelerated DNAm -aging through the risky cognitions and substance use (i.e., behavioral) pathway outlined by Gibbons et al. (). Harshness is also associated with increased exposure to threat/danger, which, in turn, leads to accelerated DNAm -aging through effects on FKBP5 activity and enhanced pro-inflammatory tendencies (i.e., the danger/FKBP5 pathway).- Published
- 2022
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10. Childhood adversity is linked to adult health among African Americans via adolescent weight gain and effects are genetically moderated.
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Beach SRH, Ong ML, Lei MK, Klopack E, Carter SE, Simons RL, Gibbons FX, Lavner JA, Philibert RA, and Ye K
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- Adolescent, Adult, Body Mass Index, Humans, Risk Factors, Weight Gain genetics, Young Adult, Adverse Childhood Experiences, Black or African American genetics
- Abstract
Identifying the mechanisms linking early experiences, genetic risk factors, and their interaction with later health consequences is central to the development of preventive interventions and identifying potential boundary conditions for their efficacy. In the current investigation of 412 African American adolescents followed across a 20-year period, we examined change in body mass index (BMI) across adolescence as one possible mechanism linking childhood adversity and adult health. We found associations of childhood adversity with objective indicators of young adult health, including a cardiometabolic risk index, a methylomic aging index, and a count of chronic health conditions. Childhood adversities were associated with objective indicators indirectly through their association with gains in BMI across adolescence and early adulthood. We also found evidence of an association of genetic risk with weight gain across adolescence and young adult health, as well as genetic moderation of childhood adversity's effect on gains in BMI, resulting in moderated mediation. These patterns indicated that genetic risk moderated the indirect pathways from childhood adversity to young adult health outcomes and childhood adversity moderated the indirect pathways from genetic risk to young adult health outcomes through effects on weight gain during adolescence and early adulthood.
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- 2021
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11. The effects of social adversity, discrimination, and health risk behaviors on the accelerated aging of African Americans: Further support for the weathering hypothesis.
- Author
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Simons RL, Lei MK, Klopack E, Beach SRH, Gibbons FX, and Philibert RA
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- Aging, Educational Status, Female, Health Risk Behaviors, Humans, Male, Middle Aged, Black or African American, Racism
- Abstract
Background: The weathering hypothesis views the elevated rates of illness, disability, and mortality seen among Black Americans as a physiological response to the structural barriers, material hardships, and identity threats that comprise the Black experience. While granting that lifestyle may have some significance, the fundamental explanation for heath inequalities is seen as race-related stressors that accelerate biological aging., Objective: The present study tests the weathering hypothesis by examining the impact on accelerated aging of four types of adversity frequently experienced by Black Americans. Further, we investigate whether health risk behaviors mediate the effect of these conditions., Method: Our analyses utilize data from 494 middle-age, African American men and women participating in the Family and Community Healthy Study. The newly developed GrimAge index of accelerated aging is used as an indicator of weathering. Education, income, neighborhood disadvantage, and discrimination serve as the independent variables. Three health risk behaviors - diet, exercise, and alcohol consumption - are included as potential mediators of the four types of adversity. Marital status and gender are entered as controls., Results: Multivariate analyses indicated that the four types of adversity predicted acceleration whereas marriage predicted deceleration in speed of aging. Males showed greater accelerated aging than females, but there was no evidence that gender conditioned the effect of adversity. The health risk behaviors were unrelated to accelerated aging and did not mediate the effect of the stressors., Conclusion: Modern medicine's emphasis on life style as the primary explanation for race-based health disparities ignores the way race-related adversity rooted in structural and cultural conditions serves to accelerate biological decline, thereby increasing risk of early onset of illness and death. Importantly, these social conditions can only be addressed through social policies and programs that target institutional racism and promote economic equity., (Copyright © 2020. Published by Elsevier Ltd.)
- Published
- 2021
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12. Inflammatory biomarker relationships with helper T cell GPR15 expression and cannabis and tobacco smoking.
- Author
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Andersen AM, Lei MK, Beach SRH, and Philibert RA
- Subjects
- Adult, Biomarkers blood, Female, Humans, Male, Receptors, G-Protein-Coupled metabolism, Receptors, Peptide metabolism, Cannabis metabolism, Inflammation blood, Receptors, G-Protein-Coupled biosynthesis, Receptors, Peptide biosynthesis, T-Lymphocytes, Helper-Inducer metabolism, Tobacco Smoking blood
- Abstract
Objective: Smoking is associated with numerous inflammatory and autoimmune conditions. The goal of this study was to examine whether increased expression of G-protein-coupled receptor 15 (GPR15) on helper T cells in smokers could predispose to these conditions through its relationship with inflammatory biomarkers., Methods: We used flow cytometric measurement of GPR15
+ CD3+ CD4+ helper T cells and serum assays for C-reactive protein (CRP) and 17 cytokines drawn from peripheral blood samples from a cohort of n = 62 primarily African American young adults (aged 27-35 years). These variables were examined cross-sectionally in conjunction with serum biomarkers of tobacco (cotinine) and cannabis (tetrahydrocannabinol) use and lifestyle factors potentially impacting immune function in correlational analyses and linear regression models., Results: Tobacco and cannabis smoking were strongly associated with increased GPR15 expression on helper T cells (p < 0.001), which was in turn was strongly associated with the ratio of pro-inflammatory to anti-inflammatory cytokines (p < 0.001). Mediation analyses indicated increased GPR15 expression accounted for roughly half of the relationship between smoking variables and pro-inflammatory to anti-inflammatory cytokine balance. CRP was not associated with cannabis or tobacco use or GPR15+ expression, but was associated with body mass index (p < 0.001). These relationships persisted after controlling for lifestyle and medical factors impacting immune function., Conclusions: Increased expression of GPR15 by helper T cells in smokers may mediate some of the relationship between smoking and a pro-inflammatory cytokine milieu. Better understanding of this relationship may help uncover how smoking increases the risk of inflammatory diseases., (Published by Elsevier Inc.)- Published
- 2021
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13. The Effect of Tobacco Smoking Differs across Indices of DNA Methylation-Based Aging in an African American Sample: DNA Methylation-Based Indices of Smoking Capture These Effects.
- Author
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Lei MK, Gibbons FX, Simons RL, Philibert RA, and Beach SRH
- Subjects
- Adult, Black or African American genetics, Aged, Aging pathology, CpG Islands genetics, Female, Humans, Male, Middle Aged, Self Report, Smoking adverse effects, Smoking genetics, Telomere Homeostasis genetics, Tobacco Smoking adverse effects, Tobacco Smoking pathology, Aging genetics, DNA Methylation genetics, Epigenesis, Genetic, Tobacco Smoking genetics
- Abstract
Smoking is one of the leading preventable causes of morbidity and mortality worldwide, prompting interest in its association with DNA methylation-based measures of biological aging. Considerable progress has been made in developing DNA methylation-based measures that correspond to self-reported smoking status. In addition, assessment of DNA methylation-based aging has been expanded to better capture individual differences in risk for morbidity and mortality. Untested to date, however, is whether smoking is similarly related to older and newer indices of DNA methylation-based aging, and whether DNA methylation-based indices of smoking can be used in lieu of self-reported smoking to examine effects on DNA methylation-based aging measures. In the current investigation we examine mediation of the impact of self-reported cigarette consumption on accelerated, intrinsic DNA methylation-based aging using indices designed to predict chronological aging, phenotypic aging, and mortality risk, as well as a newly developed DNA methylation-based measure of telomere length. Using a sample of 500 African American middle aged smokers and non-smokers, we found that a) self-reported cigarette consumption was associated with accelerated intrinsic DNA methylation-based aging on some but not all DNA methylation-based aging indices, b) for those aging outcomes associated with self-reported cigarette consumption, DNA methylation-based indicators of smoking typically accounted for greater variance than did self-reported cigarette consumption, and c) self-reported cigarette consumption effects on DNA methylation-based aging indices typically were fully mediated by DNA methylation-based indicators of smoking (e.g., PACKYRS from GrimAge; or cg05575921 CpG site). Results suggest that when DNA methylation-based indices of smoking are substituted for self-reported assessments of smoking, they will typically fully reflect the varied impact of cigarette smoking on intrinsic, accelerated DNA methylation-based aging.
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- 2020
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14. Cigarette and Cannabis Smoking Effects on GPR15+ Helper T Cell Levels in Peripheral Blood: Relationships with Epigenetic Biomarkers.
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Andersen AM, Lei MK, Beach SRH, Philibert RA, Sinha S, and Colgan JD
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- Adult, Cigarette Smoking genetics, CpG Islands, Epigenesis, Genetic, Female, Flow Cytometry, Genetic Association Studies, Humans, Linear Models, Marijuana Smoking genetics, Basic Helix-Loop-Helix Transcription Factors genetics, Cigarette Smoking immunology, Marijuana Smoking immunology, Receptors, G-Protein-Coupled metabolism, Receptors, Peptide metabolism, Repressor Proteins genetics, T-Lymphocytes, Helper-Inducer metabolism
- Abstract
Background : Smoking causes widespread epigenetic changes that have been linked with an increased risk of smoking-associated diseases and elevated mortality. Of particular interest are changes in the level of T cells expressing G-protein-coupled receptor 15 (GPR15), a chemokine receptor linked with multiple autoimmune diseases, including inflammatory bowel disease, multiple sclerosis and psoriasis. Accordingly, a better understanding of the mechanisms by which smoking influences variation in the GPR15
+ helper T cell subpopulation is of potential interest. Methods : In the current study, we used flow cytometry and digital PCR assays to measure the GPR15+ CD3+ CD4+ populations in peripheral blood from a cohort of n = 62 primarily African American young adults (aged 27-35 years) with a high rate of tobacco and cannabis use. Res u l ts: We demonstrated that self-reported tobacco and cannabis smoking predict GPR15+ CD3+ CD4+ helper T cell levels using linear regression models. Further, we demonstrated that methylation of two candidate CpGs, cg19859270, located in GPR15 , and cg05575921, located in the gene Aryl Hydrocarbon Receptor Repressor ( AHRR ), were both significant predictors of GPR15+ CD3+ CD4+ cell levels, mediating the relationship between smoking habits and increases in GPR15+ CD3+ CD4+ cells. As hypothesized, the interaction between cg05575921 and cg19859270 was also significant, indicating that low cg05575921 methylation was more strongly predictive of GPR15+ CD3+ CD4+ cell levels for those who also had lower cg19859270 methylation. Conclusions : Smoking leads changes in two CpGs, cg05575921 and cg19859270, that mediate 38.5% of the relationship between tobacco and cannabis smoking and increased GPR15+ Th levels in this sample. The impact of cg19859270 in amplifying the association between cg05575921 and increased GPR15+ Th levels is of potential theoretical interest given the possibility that it reflects a permissive interaction between different parts of the adaptive immune system., Competing Interests: The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results. The use of DNA methylation to assess smoking status is covered by US patent 8,637,652 and other pending claims. Dr. Philibert is a potential royalty recipient on those intellectual right claims. Dr. Philibert is also an officer and stockholder of Behavioral Diagnostics. (www.bdmethylation.com).- Published
- 2020
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15. Neighborhood Disadvantage and Biological Aging: Using Marginal Structural Models to Assess the Link Between Neighborhood Census Variables and Epigenetic Aging.
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Lei MK, Simons RL, Beach SRH, and Philibert RA
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- Aging, Premature genetics, Censuses, Female, Humans, Longitudinal Studies, Middle Aged, Models, Statistical, Vulnerable Populations statistics & numerical data, Black or African American statistics & numerical data, Aging genetics, Epigenesis, Genetic genetics, Residence Characteristics statistics & numerical data, Socioeconomic Factors
- Abstract
Objectives: Past research has reported an association between neighborhood disadvantage and healthy aging, but most of these studies utilize self-report measures of health or physical functioning and do not properly account for neighborhood selection effects, creating concerns regarding inflated associations. To overcome these limitations and provide a more stringent estimate of effects, the current study investigated the effect of neighborhood disadvantage on aging using newly developed epigenetic methods to assess rate of biological aging and marginal structural modeling (MSM) to account for potential confounds due to neighborhood selection., Methods: We tested the hypothesis that neighborhood disadvantage accelerates aging using U.S. census data and five waves of interview data from a sample of 100 middle-aged African American women. Using a recently developed epigenetic index of aging, biological age was measured using weighted methylation values at 71 CpG sites. We calculated a measure of accelerated methylomic aging (in years) based upon the residual scores resulting from a regression of methylomic age on chronological age., Results: Controlling for a variety of individual difference factors that could be confounded with neighborhood effects, including various health behaviors, neighborhood disadvantage was associated with accelerated biological aging. Using MSM to account for selection effects, a standard deviation increase in neighborhood disadvantage accelerated aging an average of 9 months., Conclusions: Our findings converge with prior work to provide strong evidence that neighborhood context is a significant determinant of healthy aging., (© The Author(s) 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2019
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16. Testing Life Course Models Whereby Juvenile and Adult Adversity Combine to Influence Speed of Biological Aging.
- Author
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Simons RL, Lei MK, Beach SRH, Simons LG, Barr AB, Gibbons FX, and Philibert RA
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- Adolescent, Adult, Black or African American, Databases, Factual, Female, Georgia, Health Status Disparities, Humans, Iowa, Male, Regression Analysis, Resilience, Psychological, Aging blood, Aging physiology, Aging psychology, Stress, Psychological
- Abstract
The present study extends prior research on the links between social adversity and aging by employing more comprehensive measures of adversity and a new gene expression index of aging. Hierarchical regression and 20 years of data from a sample of 381 black Americans were used to test models regarding the impact of social adversity on speed of aging. Consistent with the early life sensitivity model, early adversity continued to predict accelerated aging after controlling for adult adversity. Contrary to the pathway model, adult adversity was not related to aging following controls for early adversity. The cumulative stress model received partial support as high adversity during adulthood amplified the effect of early adversity on aging. Finally, consonant with the social change model, low adversity during adulthood buffered the effect of early adversity on aging. These findings held after controlling for health behaviors such as smoking, diet, and exercise.
- Published
- 2019
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17. Inflammation mediates the effect of discrimination, religiosity, and friendship network on expression of the Tp53 cancer suppressor gene.
- Author
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Simons RL, Lei MK, Carter S, Beach SRH, Gibbons FX, Gerrard M, and Philibert RA
- Abstract
Objective: Chronic inflammation and expression of the TP53 gene are two biomarkers that have been identified as particularly important in the etiology and progression of cancer. While much is known about the determinants of inflammation, there is currently little information regarding the causes of variation in the functioning of TP53 , even though it has been recognized for 40 years as the most potent of the cancer suppressor genes. The current paper explores the interrelationship between these two biomarkers and investigates the extent to which they are influenced by the social environment., Methods: Using structural equation modeling (SEM) and longitudinal observational data from a sample of several hundred African Americans, we tested the hypothesis that adversity - operationalized as racial discrimination- and coping resources - operationalized as religiosity and black friends - influence expression of TP53 , for better or worse, through their impact on inflammation., Results: Correlational analysis showed inflammation and TP53 to be inversely related. Further, discrimination was positively related to inflammation and negatively related to TP53 expression, whereas religiosity and black friends were both negatively related to inflammation and positively related to TP53 expression. Finally, SEM indicated that the effect of the social environmental variables on TP53 expression was indirect through level of inflammation., Conclusions: In addition to its established contribution to cancer through DNA damage and cell proliferation, inflammation likely increases cancer risk indirectly by inhibiting expression of the TP53 cancer suppressor gene. Hence environmental and stress management interventions may do more than reduce inflammation's cell damaging effects; they may also lessen the chances of cancer by increasing expression of TP53 .
- Published
- 2019
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18. Perceived relationship support moderates the association of contextual stress with inflammation among African Americans.
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Beach SRH, Lei MK, Simons RL, Barr AB, Simons LG, Cutrona CE, and Philibert RA
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- Adult, Cytokines immunology, Cytokines metabolism, Economics, Female, Humans, Inflammation Mediators immunology, Longitudinal Studies, Male, Social Perception, Socioeconomic Factors, Stress, Psychological psychology, Young Adult, Black or African American psychology, Crime Victims psychology, Inflammation immunology, Inflammation psychology, Racism psychology, Sexual Partners psychology, Social Support, Stress, Psychological immunology
- Abstract
We followed 402 African American young adults from ages 24 to 29, a period of emerging committed relationships, to examine the association of contextual stress (CS), for example, experiences of financial strain, victimization, and racial discrimination, with inflammation, and to test predictions that greater perceived relationship warmth and support (PRWS) at age 29 would moderate the association between earlier CS and inflammation, using a multiplex assessment of cytokines to construct an index of the ratio between predominantly proinflammatory cytokines versus predominantly anti-inflammatory cytokines. CS experienced at age 24 was associated with greater inflammation at age 29 in the full sample (b = .112, p = .004). PRWS at age 29 moderated the association of earlier CS with inflammation (b = -.114, p = .011), but there was no significant main effect of PRWS (b = -.053, p = .265). Finally, using an internal moderator approach, we compared the association of CS with inflammation among those not in a committed relationship to those in more or less supportive relationships, showing a significant and stronger association of CS with inflammation for those with low PRWS (-1 SD; b = .182, p < .001), a weaker and nonsignificant association of CS with inflammation among those with higher PRWS (+1 SD; b = -.002, p = .975), and an intermediate and nonsignificant association of CS with inflammation among those with no committed romantic relationship (b = .077, p = .227). Results were robust to number of cytokines included in the inflammation index. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
- Published
- 2019
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19. AHRR Methylation is a Significant Predictor of Mortality Risk in Framingham Heart Study.
- Author
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Philibert RA, Dogan MV, Mills JA, and Long JD
- Subjects
- Aged, Aged, 80 and over, Cardiovascular Diseases epidemiology, Epigenesis, Genetic, Female, Humans, Longitudinal Studies, Male, Massachusetts epidemiology, Middle Aged, Proportional Hazards Models, Risk Factors, Smoking epidemiology, Alcohol Drinking adverse effects, Basic Helix-Loop-Helix Transcription Factors genetics, DNA Methylation, Genetic Loci, Mortality, Repressor Proteins genetics
- Abstract
Background.- The ability to predict mortality is useful to clinicians, policy makers and insurers. At the current time, prediction of future mortality is still an inexact process with some proposing that epigenetic assessments could play a role in improving prognostics. In past work, we and others have shown that DNA methylation status at cg05575921, a well-studied measure of smoking intensity, is also a predictor of mortality. However, the exact extent of that predictive capacity and its independence of other commonly measured mortality risk factors are unknown. Objective.- To determine the capacity of methylation to predict mortality. Method.- We analyzed the relationship of methylation at cg05575921 and cg04987734, a recently described quantitative marker of heavy alcohol consumption, to mortality in the Offspring Cohort of the Framingham Heart Study using proportional hazards survival analysis. Results.- In this group of participants (n = 2278) whose average age was 66 ± 9 years, we found that the inclusion of both cg05575921 and cg04987734 methylation to a base model consisting of age and sex only, or to a model containing 11 commonly used mortality risk factors, improved risk prediction. What is more, prediction accuracy for the base model plus methylation data was increased compared to the base model plus known predictors of mortality (CHD, COPD, or stroke). Conclusion.- Cg05575921, and to a smaller extent cg04987734, are strong predictors of mortality risk in older Americans and that incorporation of DNA methylation assessments to these and other loci may be useful to population scientists, actuaries and policymakers to better understand the relationship of environmental risk factors, such as smoking and drinking, to mortality.
- Published
- 2019
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20. Blood-Based Biomarkers for Predicting the Risk for Five-Year Incident Coronary Heart Disease in the Framingham Heart Study via Machine Learning.
- Author
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Dogan MV, Beach SRH, Simons RL, Lendasse A, Penaluna B, and Philibert RA
- Abstract
An improved approach for predicting the risk for incident coronary heart disease (CHD) could lead to substantial improvements in cardiovascular health. Previously, we have shown that genetic and epigenetic loci could predict CHD status more sensitively than conventional risk factors. Herein, we examine whether similar machine learning approaches could be used to develop a similar panel for predicting incident CHD. Training and test sets consisted of 1180 and 524 individuals, respectively. Data mining techniques were employed to mine for predictive biosignatures in the training set. An ensemble of Random Forest models consisting of four genetic and four epigenetic loci was trained on the training set and subsequently evaluated on the test set. The test sensitivity and specificity were 0.70 and 0.74, respectively. In contrast, the Framingham risk score and atherosclerotic cardiovascular disease (ASCVD) risk estimator performed with test sensitivities of 0.20 and 0.38, respectively. Notably, the integrated genetic-epigenetic model predicted risk better for both genders and very well in the three-year risk prediction window. We describe a novel DNA-based precision medicine tool capable of capturing the complex genetic and environmental relationships that contribute to the risk of CHD, and being mapped to actionable risk factors that may be leveraged to guide risk modification efforts.
- Published
- 2018
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21. Methylation of MTHFR Moderates the Effect of Smoking on Genomewide Methylation Among Middle Age African Americans.
- Author
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Andersen AM, Lei MK, Philibert RA, and Beach SRH
- Abstract
Differential methylation at MTHFR (m MTHFR) has been examined previously as a moderator of changes in methylation among nascent smokers, but the effects of mMTHFR on genomewide patterns of methylation among established smokers in middle age are unknown. In the current investigation we examined a sample of 180 African American middle-aged smokers and non-smokers to test for patterns indicative of three different potential mechanisms of impact on epigenetic remodeling in response to long-term smoking. We found that m MTHFR moderated the association between smoking and changes in methylation for more than 25% of the 909 loci previously identified as being associated with smoking at a genomewide level of significance in middle-aged African Americans. Observed patterns of effect indicated amplification of both hyper and hypo methylating responses to smoking among those with lower m MTHFR . Moderating effects were robust to controls for sex, age, diet, and cell-type variation. Implications for potential mechanisms conferring effects are discussed. Of particular potential practical importance was a strong effect of m MTHFR on hypomethylation at GPR15 in response to smoking, indicative of the differential impact of MTHFR activity on changes in a specific cell population linked to inflammatory disease in smokers.
- Published
- 2018
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22. Discrimination, segregation, and chronic inflammation: Testing the weathering explanation for the poor health of Black Americans.
- Author
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Simons RL, Lei MK, Beach SRH, Barr AB, Simons LG, Gibbons FX, and Philibert RA
- Subjects
- Adolescent, Adult, Child, Chronic Disease ethnology, Female, Humans, Longitudinal Studies, Male, Models, Theoretical, Stress, Psychological complications, Young Adult, Black or African American psychology, Health Status Disparities, Inflammation ethnology, Inflammation etiology, Racism psychology, Stress, Psychological ethnology
- Abstract
Several studies have reported a relation between race-related stressors and the poor health of Black Americans. Such findings raise questions regarding the mediating biological mechanisms that might account for this link. The present study investigated elevated systemic inflammation, a factor shown to be a strong predictor of chronic illness and mortality in all ethnic populations, as a possible factor. Using 7 waves of data from the Family and Community Health Study, collected over a 20-year period from over 400 Black Americans, we investigated the extent to which exposure to discrimination and segregation at various points in the life course predicted adult inflammation at age 28. Our analyses examined whether cumulative stress, stress generation, or predictive adaptive response (PAR) models best accounted for any associations that existed between these race-related stressors and adult inflammation. At every wave of data collection, assessments of discrimination and segregation were related to adult inflammation. However, multivariate analyses using structure equation modeling indicated that the PAR model best explained the effect of these race-related stressors on inflammation. Exposure to discrimination and segregation during the juvenile years predicted adult inflammation and amplified the inflammatory effect of adult exposure to these race-related stressors. These effects were considerably more robust than that of traditional health risk factors such as diet, exercise, smoking, and low SES. Implications of these findings are discussed, including the limitations of the widely accepted risk factor approach to increasing the health of Black Americans. (PsycINFO Database Record, ((c) 2018 APA, all rights reserved).)
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- 2018
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23. Would Addressing Alcohol Consumption Further Account for Variance in Methylation?
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Philibert RA and Beach SRH
- Subjects
- Alcohol Drinking, Epigenesis, Genetic, Smoking, Crime Victims, DNA Methylation
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- 2018
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24. MTHFR regulatory effects on methylation of CG05575921 in response to smoking: Effects are also discernable using MTHFR expression.
- Author
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Beach SRH, Lei MK, Simons RL, Dogan MV, Gibbons FX, and Philibert RA
- Subjects
- Adult, Black or African American, Basic Helix-Loop-Helix Transcription Factors physiology, DNA Methylation genetics, Enhancer Elements, Genetic genetics, Female, Gene Expression drug effects, Humans, Male, Methylenetetrahydrofolate Reductase (NADPH2) physiology, Repressor Proteins physiology, Self Report, Smoking, Young Adult, Basic Helix-Loop-Helix Transcription Factors genetics, Cigarette Smoking genetics, Methylenetetrahydrofolate Reductase (NADPH2) genetics, Repressor Proteins genetics
- Published
- 2018
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25. Sharing the Burden of the Transition to Adulthood: African American Young Adults' Transition Challenges and Their Mothers' Health Risk.
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Barr AB, Simons LG, Simons RL, Beach SRH, and Philibert RA
- Abstract
For many African American youth, the joint influences of economic and racial marginalization render the transition to stable adult roles challenging. We have gained much insight into how these challenges affect future life chances, yet we lack an understanding of what these challenges mean in the context of linked lives. Drawing on a life course framework, this study examines how young African Americans' experiences across a variety of salient domains during the transition to adulthood affect their mothers' health. Results suggest that stressors experienced by African Americans during the transition to adulthood (e.g., unemployment, troubled romantic relationships, arrest) heighten their mothers' cumulative biological risk for chronic diseases, or allostatic load, and reduce subjective health. These results suggest that the toll of an increasingly tenuous and uncertain transition to adulthood extends beyond young people to their parents. Hence, increased public investments during this transition may not only reduce inequality and improve life chances for young people themselves, but may also enhance healthy aging by relieving the heavy burden on parents to help their children navigate this transition.
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- 2018
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26. Integrated genetic and epigenetic prediction of coronary heart disease in the Framingham Heart Study.
- Author
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Dogan MV, Grumbach IM, Michaelson JJ, and Philibert RA
- Subjects
- Aged, Aged, 80 and over, DNA Methylation, Female, Humans, Machine Learning, Male, Models, Theoretical, Phenotype, Polymorphism, Single Nucleotide, Risk Factors, United States, Coronary Disease genetics, Epigenomics
- Abstract
An improved method for detecting coronary heart disease (CHD) could have substantial clinical impact. Building on the idea that systemic effects of CHD risk factors are a conglomeration of genetic and environmental factors, we use machine learning techniques and integrate genetic, epigenetic and phenotype data from the Framingham Heart Study to build and test a Random Forest classification model for symptomatic CHD. Our classifier was trained on n = 1,545 individuals and consisted of four DNA methylation sites, two SNPs, age and gender. The methylation sites and SNPs were selected during the training phase. The final trained model was then tested on n = 142 individuals. The test data comprised of individuals removed based on relatedness to those in the training dataset. This integrated classifier was capable of classifying symptomatic CHD status of those in the test set with an accuracy, sensitivity and specificity of 78%, 0.75 and 0.80, respectively. In contrast, a model using only conventional CHD risk factors as predictors had an accuracy and sensitivity of only 65% and 0.42, respectively, but with a specificity of 0.89 in the test set. Regression analyses of the methylation signatures illustrate our ability to map these signatures to known risk factors in CHD pathogenesis. These results demonstrate the capability of an integrated approach to effectively model symptomatic CHD status. These results also suggest that future studies of biomaterial collected from longitudinally informative cohorts that are specifically characterized for cardiac disease at follow-up could lead to the introduction of sensitive, readily employable integrated genetic-epigenetic algorithms for predicting onset of future symptomatic CHD.
- Published
- 2018
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27. Prevention of Early Substance Use Mediates, and Variation at SLC6A4 Moderates, SAAF Intervention Effects on OXTR Methylation.
- Author
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Beach SRH, Lei MK, Brody GH, and Philibert RA
- Subjects
- Adolescent, Child, Female, Genotype, Georgia, Humans, Male, Outcome Assessment, Health Care, Preventive Health Services, Rural Population, Young Adult, Black or African American genetics, DNA Methylation genetics, Receptors, Oxytocin genetics, Serotonin Plasma Membrane Transport Proteins genetics, Substance-Related Disorders genetics, Substance-Related Disorders prevention & control
- Abstract
The Strong African American Family (SAAF) program has been shown to have a variety of short and long-term benefits for participating youth and families. However, biological mechanisms potentially influencing long-term effects on resilience in young adulthood have not been examined. In the current investigation, we examine the effects of SAAF on methylation of the OXTR gene in young adulthood, focusing on a regulatory region previously identified to be both responsive to stress and implicated in resilience. Using the subsample of participants from the original study for whom methylation data was available (N = 388), we replicated the previously reported G × E effect on prevention of early substance use and then examined whether there would also be a moderated effect on OXTR methylation in early adulthood, with "s" allele carriers, but not "LL" participants, showing a significant indirect effect of SAAF on OXTR methylation. Results suggest that for susceptible youth (i.e., "s" allele carriers), preventive intervention may "get under the skin," in a manner potentially beneficial for long-term outcomes. Implications for examination of OXTR methylation in future prevention research are discussed.
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- 2018
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28. A Droplet Digital PCR Assay for Smoking Predicts All-Cause Mortality.
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Andersen AM, Ryan PT, Gibbons FX, Simons RL, Long JD, and Philibert RA
- Subjects
- Adult, Aged, Epigenesis, Genetic, Female, Humans, Longitudinal Studies, Male, Middle Aged, Polymerase Chain Reaction, Predictive Value of Tests, Risk Factors, Biomarkers, DNA Methylation, Epigenomics, Tobacco Smoking mortality
- Abstract
Objectives: -Determine whether an epigenetic assay for smoking predicts all-cause mortality in adults participating in a longitudinal study of Iowa adoptees., Background: -Improved biomarkers for smoking are needed given its large public health impact and significant limitations of both self-report and current biomarkers, such as cotinine in detecting smoking. In the past 5 years, multiple epigenome-wide association studies of smoking have identified loci suitable for translation as epigenetic biomarkers for smoking, in particular the CpG cg05575921. Digital polymerase chain reaction methods hold promise for the development of this and other epigenetic biomarkers., Methods: -Participants in the Iowa Adoption Studies were interviewed regarding their smoking habits. DNA was prepared from whole blood and bisulfite-converted for methylation analysis and digital droplet polymerase chain reaction assay of methylation at cg05575921 was performed. National Death Index records were requested for 584 study participants, resulting in 24 complete matches, 210 partial matches and 350 non-matching records. Complete matches were coded as deceased while the remainder were coded as alive (ie, censored). In total, methylation data and vital status information were available for a total of N = 193 subjects, including 15 deceased and 178 non-deceased. Cox regression was used to examine the ability of cg05575921 methylation as a continuous value to predict the timing of mortality with and without the inclusion of age, sex, race, BMI, marital status, educational status, socioeconomic status, cardiovascular risk factors, and a history of cancer as covariates., Results: -Methylation at cg05575921 predicted the hazard of mortality as the sole predictor and after accounting for major demographic and clinical risk factors. The fitted model showed the hazard ratio increased by 3.5% for every 1% decrease in methylation., Conclusions: -Decreased methylation at cg05575921, an emerging epigenetic biomarker for smoking, was associated with early mortality in a longitudinal study of adults after accounting for the impact of major demographic and clinical risk factors for all-cause mortality. This approach may be useful in clinical research or actuarial assessments.
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- 2018
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29. When inflammation and depression go together: The longitudinal effects of parent-child relationships.
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Beach SRH, Lei MK, Simons RL, Barr AB, Simons LG, Ehrlich K, Brody GH, and Philibert RA
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- Adolescent, Adult, Child, Depression immunology, Female, Humans, Longitudinal Studies, Male, Parenting, Prospective Studies, Sexual Partners, Stress, Psychological psychology, Young Adult, Black or African American psychology, Depression psychology, Inflammation, Interpersonal Relations, Parent-Child Relations, Stress, Psychological immunology
- Abstract
Parent-child relationships have long-term effects on health, particularly later inflammation and depression. We hypothesized that these effects would be mediated by later romantic partner relationships and elevated stressors in young adulthood, helping promote chronic, low grade, inflammation as well as depressive symptoms, and driving their covariation. It has been proposed recently that youth experiencing harsher parenting may also develop a stronger association between inflammation and depressive symptoms in adulthood and altered effects of stressors on outcomes. In the current investigation, we test these ideas using an 18-year longitudinal study of N = 413 African American youth that provides assessment of the parent-child relationship (at age 10), pro-inflammatory cytokine profile and depressive symptoms (at age 28), and potential mediators in early young adulthood (assessed at ages 21 and 24). As predicted, the effect of harsher parent-child relationships (age 10) on pro-inflammatory state and increased depressive symptoms at age 28 were fully mediated through young adult stress and romantic partner relationships. In addition, beyond these mediated effects, parent-child relationships at age 10 moderated the concurrent association between inflammation and depressive symptoms, as well as the prospective association between romantic partner relationships and inflammation, and resulted in substantially different patterns of indirect effects from young adult mediators to outcomes. The results support theorizing that the association of depression and inflammation in young adulthood is conditional on earlier parenting, and suggest incorporating this perspective into models predicting long-term health outcomes.
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- 2017
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30. Childhood/Adolescent stressors and allostatic load in adulthood: Support for a calibration model.
- Author
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Berg MT, Simons RL, Barr A, Beach SRH, and Philibert RA
- Subjects
- Adult, Biomarkers analysis, Biomarkers blood, Black People ethnology, Blood Pressure, Body Mass Index, C-Reactive Protein analysis, Female, Georgia, Glycated Hemoglobin analysis, Humans, Interleukin-6 analysis, Interleukin-6 blood, Iowa, Longitudinal Studies, Male, Middle Aged, Multivariate Analysis, Stress, Psychological ethnology, Black or African American, Allostasis, Black People statistics & numerical data, Life Change Events, Mothers statistics & numerical data, Stress, Psychological complications
- Abstract
Rationale: Past research has established an association between childhood and adolescent stressors and elevated inflammatory and metabolic biomarkers in adulthood, but questions remain about the theoretical model most suited to explain this association., Objective: This study examined alternative hypotheses from four theoretical models regarding the link between exposure to stressful early life circumstances and cumulative biological risk, or allostatic load, in adulthood., Methods: Multivariate regression models and data from a sample of 327 African American women from the Family and Community Health Study were used to test hypotheses., Results: Stressors measured during the phases of childhood and adolescence predicted increased allostatic load, irrespective of adult circumstances that might account for this effect. Also, these early stressors conditioned the health effects of adult positive and negative circumstances. Exposure to childhood and adolescent stressors amplified the effect of adult economic hardship on allostatic load and dulled the beneficial effects of positive events and high-quality relationships., Conclusion: These findings support the perspective that childhood and adolescence are phases when exposure to adversities possibly enhances vulnerability to biological risk in adulthood irrespective of later life circumstances. Also, the findings are consistent with the perspective that childhood and adolescent adversities calibrate biological risk resulting from aversive and positive features of the adult social environment., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
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- 2017
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31. MTHFR methylation moderates the impact of smoking on DNA methylation at AHRR for African American young adults.
- Author
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Beach SRH, Lei MK, Ong ML, Brody GH, Dogan MV, and Philibert RA
- Subjects
- Adolescent, Adult, Epigenesis, Genetic, Humans, Male, Young Adult, Black or African American genetics, Basic Helix-Loop-Helix Transcription Factors genetics, DNA Methylation, Methylenetetrahydrofolate Reductase (NADPH2) genetics, Repressor Proteins genetics, Smoking genetics
- Abstract
Smoking has been shown to have a large, reliable, and rapid effect on demethylation of AHRR, particularly at cg05575921, suggesting that methylation may be used as an index of cigarette consumption. Because the availability of methyl donors may also influence the degree of demethylation in response to smoking, factors that affect the activity of methylene tetrahydrofolate reductase (MTHFR), a key regulator of methyl group availability, may be of interest. In the current investigation, we examined the extent to which individual differences in methylation of MTHFR moderated the association between smoking and demethylation at cg05575921 as well as at other loci on AHRR associated with a main effect of smoking. Using a discovery sample (AIM, N = 293), and a confirmatory sample (SHAPE, N = 368) of young adult African Americans, degree of methylation of loci in the first exon of MTHFR was associated with amplification of the association between smoking and AHRR demethylation at cg05575921. However, genetic variation at a commonly studied MTHFR variant, C677T, did not influence cg05575921 methylation. The significant interaction between MTHFR methylation and the smoking-induced response at cg05575921 suggests a role for individual differences in methyl cycle regulation in understanding the effects of cigarette consumption on genome wide DNA methylation., (© 2017 Wiley Periodicals, Inc.)
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- 2017
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32. Genetically contextual effects of smoking on genome wide DNA methylation.
- Author
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Dogan MV, Beach SRH, and Philibert RA
- Subjects
- Female, Genome, Human, Humans, Longitudinal Studies, Male, DNA Methylation, Epigenesis, Genetic, Genetic Markers, Genome-Wide Association Study, Smoking genetics
- Abstract
Smoking is the leading cause of death in the United States. It exerts its effects by increasing susceptibility to a variety of complex disorders among those who smoke, and if pregnant, to their unborn children. In prior efforts to understand the epigenetic mechanisms through which this increased vulnerability is conveyed, a number of investigators have conducted genome wide methylation analyses. Unfortunately, secondary to methodological limitations, these studies were unable to examine methylation in gene regions with significant amounts of genetic variation. Using genome wide genetic and epigenetic data from the Framingham Heart Study, we re-examined the relationship of smoking status to genome wide methylation status. When only methylation status is considered, smoking was significantly associated with differential methylation in 310 genes that map to a variety of biological process and cellular differentiation pathways. However, when SNP effects on the magnitude of smoking associated methylation changes are also considered, cis and trans-interaction effects were noted at a total of 266 and 4353 genes with no marked enrichment for any biological pathways. Furthermore, the SNP variation participating in the significant interaction effects is enriched for loci previously associated with complex medical illnesses. The enlarged scope of the methylome shown to be affected by smoking may better explicate the mediational pathways linking smoking with a myriad of smoking related complex syndromes. Additionally, these results strongly suggest that combined epigenetic and genetic data analyses may be critical for a more complete understanding of the relationship between environmental variables, such as smoking, and pathophysiological outcomes., (© 2017 Wiley Periodicals, Inc.)
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- 2017
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33. Accuracy and utility of an epigenetic biomarker for smoking in populations with varying rates of false self-report.
- Author
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Andersen AM, Philibert RA, Gibbons FX, Simons RL, and Long J
- Subjects
- Adult, Case-Control Studies, DNA Methylation, Female, Humans, Male, Biomarkers analysis, Epigenomics, Self Report statistics & numerical data, Smoking blood, Truth Disclosure
- Abstract
Better biomarkers to detect smoking are needed given the tremendous public health burden caused by smoking. Current biomarkers to detect smoking have significant limitations, notably a short half-life for detection and lack of sensitivity for light smokers. These limitations may be particularly problematic in populations with less accurate self-reporting. Prior epigenome-wide association studies indicate that methylation status at cg05575921, a CpG residue located in the aryl hydrocarbon receptor repressor (AHRR) gene, may be a robust indicator of smoking status in individuals with as little as half of a pack-year of smoking. In this study, we show that a novel droplet digital PCR assay for measuring methylation at cg05575921 can reliably detect smoking status, as confirmed by serum cotinine, in populations with different demographic characteristics, smoking histories, and rates of false-negative self-report of smoking behavior. Using logistic regression models, we show that obtaining maximum accuracy in predicting smoking status depends on appropriately weighting self-report and cg05575921 methylation according to the characteristics of the sample being tested. Furthermore, models using only cg05575921 methylation to predict smoking perform nearly as well as those also including self-report across populations. In conclusion, cg05575921 has significant potential as a clinical biomarker to detect smoking in populations with varying rates of accuracy in self-report of smoking behavior., (This article is a U.S. Government work and is in the public domain in the USA.)
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- 2017
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34. Methylation of the oxytocin receptor gene mediates the effect of adversity on negative schemas and depression.
- Author
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Simons RL, Lei MK, Beach SRH, Cutrona CE, and Philibert RA
- Subjects
- Adult, DNA Methylation, Female, Follow-Up Studies, Humans, Middle Aged, Stress, Psychological genetics, Depression etiology, Depression genetics, Depression psychology, Pessimism psychology, Poverty psychology, Receptors, Oxytocin genetics, Stress, Psychological psychology, Trust psychology
- Abstract
Building upon various lines of research, we posited that methylation of the oxytocin receptor gene (OXTR) would mediate the effect of adult adversity on increased commitment to negative schemas and in turn the development of depression. We tested our model using structural equation modeling and longitudinal data from a sample of 100 middle-aged, African American women. The results provided strong support for the model. Analysis of the 12 CpG sites available for the promoter region of the OXTR gene identified four factors. One of these factors was related to the study variables, whereas the others were not. This factor mediated the effect of adult adversity on schemas relating to pessimism and distrust, and these schemas, in turn, mediated the impact of OXTR methylation on depression. All indirect effects were statistically significant, and they remained significant after controlling for childhood trauma, age, romantic relationship status, individual differences in cell types, and average level of genome-wide methylation. These finding suggest that epigenetic regulation of the oxytocin system may be a mechanism whereby the negative cognitions central to depression become biologically embedded.
- Published
- 2017
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35. Smoking in young adulthood among African Americans: Interconnected effects of supportive parenting in early adolescence, proinflammatory epitype, and young adult stress.
- Author
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Beach SRH, Lei MK, Brody GH, Miller GE, Chen E, Mandara J, and Philibert RA
- Subjects
- Adolescent, Adult, Child, DNA Methylation, Female, Georgia ethnology, Humans, Male, Risk, Rural Population, Young Adult, Black or African American ethnology, Inflammation metabolism, Parenting ethnology, Smoking ethnology, Stress, Psychological ethnology, Stress, Psychological metabolism, Tumor Necrosis Factor-alpha metabolism
- Abstract
We examined two potentially interacting, connected pathways by which parental supportiveness during early adolescence (ages 1-13) may come to be associated with later African American young adult smoking. The first pathway is between parental supportiveness and young adult stress (age 19), with stress, in turn, predicting increased smoking at age 20. The second pathway is between supportive parenting and tumor necrosis factor (TNF) gene methylation (i.e., TNFm), a proinflammatory epitype, with low levels indicating greater inflammatory potential and forecasting increased risk for smoking in response to young adult stress. In a sample of 382 African American youth residing in rural Georgia, followed from early adolescence (age 10-11) to young adulthood (age 20), supportive parenting indirectly predicted smoking via associations with young adult stress, IE = -0.071, 95% confidence interval [-0.132, -0.010]. In addition, supportive parenting was associated with TNFm measured at age 20 (r = .177, p = .001). Further, lower TNFm was associated with a significantly steeper slope (b = 0.583, p = .003) of increased smoking in response to young adult stress compared to those with higher TNFm (b = 0.155, p = .291), indicating an indirect, amplifying role for supportive parenting via TNFm. The results suggest that supportive parenting in early adolescence may play a role in understanding the emergence of smoking in young adulthood.
- Published
- 2017
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36. An index of the ratio of inflammatory to antiviral cell types mediates the effects of social adversity and age on chronic illness.
- Author
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Simons RL, Lei MK, Beach SRH, Barr AB, Cutrona CE, Gibbons FX, and Philibert RA
- Subjects
- Age Factors, Biomarkers analysis, Humans, Inflammation blood, Social Norms, Cells classification, Chronic Disease, Patient Acuity, Socioeconomic Factors, Stress, Psychological complications
- Abstract
Background: It is assumed that both social stress and chronological age increase the risk of chronic illness, in part, through their effect on systemic inflammation. Unfortunately, observational studies usually employ single-marker measures of inflammation (e.g., Interleukin-6, C-reactive protein) that preclude strong tests for mediational effects., Objective: The present study investigated the extent to which the effects of socioeconomic disadvantage and age on onset of chronic illness is mediated by dominance of the innate (inflammatory) over the acquired (antiviral) components of the immune system., Methods: We assessed inflammation using the ratio of inflammatory to antiviral cell types (ITACT Ratio). This approach provided a stronger test of evolutionary arguments regarding the effect of social stress on chronic inflammation than is the case with cytokine measures, and afforded an opportunity to replicate findings obtained utilizing mRNA. We used structural equation modeling and longitudinal data from a sample of 100 middle-age African American women to perform our analyses., Results: Dominance of inflammatory over antiviral cell activity was associated with each of the eight illnesses included in our chronic illness measure. Both socioeconomic disadvantage and age were also associated with inflammatory dominance. Pursuant to the central focus of the study, the effects of socioeconomic adversity and age on increased illness were mediated by our measure of inflammatory dominance. The indirect effect of these variables through inflammatory cell profile was significant, with neither socioeconomic disadvantage nor age showing a significant association with illness once the impact of inflammatory cell profile was taken into account., Conclusions: First, the analysis provides preliminary validation of a new measure of inflammation that is calculated based on the ratio of inflammatory to antiviral white blood cells. Second, our results support the hypothesis that socioeconomic disadvantage and chronological age increase risk for chronic illness in part through their effect on inflammatory processes., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
- Published
- 2017
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37. A pilot investigation of the impact of smoking cessation on biological age.
- Author
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Lei MK, Beach SR, Dogan MV, and Philibert RA
- Subjects
- Female, Humans, Male, Middle Aged, Physical Appearance, Body physiology, Pilot Projects, Regression Analysis, Aging physiology, Aging psychology, Aging, Premature etiology, Aging, Premature prevention & control, Motivation, Smoking adverse effects, Smoking physiopathology, Smoking psychology, Smoking therapy, Smoking Cessation psychology
- Abstract
Background and Objectives: Smoking is known to increase biological age. However, whether this process is reversible through smoking cessation is not known. In this pilot study, we attempt to determine whether smoking cessation reduces biological age., Methods: We conducted regression analyses of methylation data from 22 subjects, as they entered and exited inpatient substance use treatment, to determine change in biological age, as indicated by the deviation of their methylomic age from chronological age across two time points., Results: We found that, as compared to those subjects who did not stop smoking, subjects who significantly decreased their smoking consumption over a 1 month time period exhibited a marked reduction in methylomic age., Conclusion: The rapid and substantial reversal of accelerated aging associated with successful smoking cessation suggests that it can reverse well-known smoking effects on methylomic aging. This preliminary finding can be readily examined in other, larger data sets, and if replicated, this observation may provide smokers with yet another good reason to quit smoking., Scientific Significance: Successful smoking cessation makes patients appear biologically younger than they were at baseline, and to do so quite rapidly. In today's youth driven society, our observations may serve as a powerful impetus for some to quit smoking. (Am J Addict 2017;26:129-135)., (© 2017 American Academy of Addiction Psychiatry.)
- Published
- 2017
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38. Exploring genetic moderators and epigenetic mediators of contextual and family effects: From Gene × Environment to epigenetics.
- Author
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Beach SR, Brody GH, Barton AW, and Philibert RA
- Subjects
- Adolescent, Adult, Child, Child, Preschool, Genotype, Humans, Infant, Infant, Newborn, Inflammation Mediators blood, Parenting psychology, Young Adult, Black or African American genetics, Black or African American psychology, Epigenesis, Genetic genetics, Gene-Environment Interaction
- Abstract
In the current manuscript, we provide an overview of a research program at the University of Georgia's Center for Family Research designed to expand upon rapid and ongoing developments in the fields of genetics and epigenetics. By placing those developments in the context of translational research on family and community determinants of health and well-being among rural African Americans, we hope to identify novel, modifiable environments and biological processes. In the first section of the article, we review our earlier work on genotypic variation effects on the association between family context and mental and physical health outcomes as well as differential responses to family-based intervention. We then transition to discuss our more recent research on the association of family and community environments with epigenetic processes. In this second section of the article, we begin by briefly reviewing terminology and basic considerations before describing evidence that early environments may influence epigenetic motifs that potentially serve as mediators of long-term effects of early family and community environments on longer term health outcomes. We also provide evidence that genotype may sometimes influence epigenetic outcomes. Finally, we describe our recent efforts to use genome-wide characterization of epigenetic patterns to better understand the biological impact of protective parenting on long-term shifts in inflammatory processes and its potential implications for young adult health. As will be clear, research on epigenetics as a mediator of the connections between family/community processes and a range of health outcomes is still in its infancy, but the potential to develop important insights regarding mechanisms linking modifiable environments to biological processes and long-term health outcomes already is coming into view.
- Published
- 2016
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39. Alcohol and tobacco consumption alter hypothalamic pituitary adrenal axis DNA methylation.
- Author
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Dogan MV, Lei MK, Beach SR, Brody GH, and Philibert RA
- Subjects
- Adult, Aged, Cohort Studies, Ethanol pharmacology, Female, Genome-Wide Association Study, Humans, Hypothalamo-Hypophyseal System drug effects, Male, Middle Aged, Pituitary-Adrenal System drug effects, Receptors, Glucocorticoid genetics, Tacrolimus Binding Proteins genetics, Alcohol Drinking genetics, DNA Methylation drug effects, Hypothalamo-Hypophyseal System metabolism, Pituitary-Adrenal System metabolism, Tobacco Use genetics
- Abstract
Alcohol and cigarette consumption have profound effects on genome wide DNA methylation and are common, often cryptic, comorbid features of many psychiatric disorders. This cryptic consumption is a possible impediment to understanding the biology of certain psychiatric disorders because if the effects of substance use are not taken into account, their presence may confound efforts to identify effects of other behavioral disorders. Since the hypothalamic pituitary adrenal (HPA) axis is known to be dysregulated in these disorders, we examined the potential for confounding effects of alcohol and cigarette consumption by examining their effects on peripheral DNA methylation at two key HPA axis genes, NR3C1 and FKBP5. We found that the influence of alcohol and smoke exposure is more prominent at the FKBP5 gene than the NR3C1 gene. Furthermore, in both genes, loci that were consistently significantly associated with smoking and alcohol consumption demethylated with increasing exposure. We conclude that epigenetic studies of complex disorders involving the HPA axis need to carefully control for the effects of substance use in order to minimize the possibility of type I and type II errors., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
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40. Stress, relationship satisfaction, and health among African American women: Genetic moderation of effects.
- Author
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Lei MK, Beach SR, Simons RL, Barr AB, Cutrona CE, and Philibert RA
- Subjects
- Adult, Black or African American statistics & numerical data, Alleles, Female, Genotype, Heterozygote, Humans, Models, Theoretical, Polymorphism, Genetic, Stress, Physiological genetics, Black or African American genetics, Black or African American psychology, Genetic Predisposition to Disease ethnology, Interpersonal Relations, Personal Satisfaction, Serotonin Plasma Membrane Transport Proteins genetics, Stress, Psychological ethnology
- Abstract
We examined whether romantic relationship satisfaction would serve as a link between early and later stressors which in turn would influence the thyroid function index (TFI), an indicator of physiological stress response. Using the framework of genetic susceptibility theory combined with hypotheses derived from the vulnerability-stress-adaptation and stress-generation models, we tested whether the hypothesized mediational model would be conditioned by 5-HTTLPR genotype, with greater effects and stronger evidence of mediation among carriers of the "s" allele. In a sample of African American women in romantic relationships (n = 270), we found that 5-HTTLPR moderated each stage of the hypothesized mediational model in a "for better or for worse" manner. That is genetic polymorphisms function to exacerbate not only the detrimental impact of negative environments (i.e., "for worse effects") but also the beneficial impact of positive environments (i.e., "for better effects"). The effect of early stress on relationship satisfaction was greater among carriers of the "short" allele than among those who did not carry the short allele, and was significantly different in both the "for better" and "for worse" direction. Likewise, the effect of relationship satisfaction on later stressors was moderated in a "for better "or "for worse" manner. Finally, impact on physiological stress, indexed using TFI level, indicated that the impact of later stressors on TFI level was greater in the presence of the short allele, and also followed a "for better" or "for worse" pattern. As expected, the proposed mediational model provided a better fit for "s" allele carriers., ((c) 2016 APA, all rights reserved).)
- Published
- 2016
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41. Association of the OPRM1 Variant rs1799971 (A118G) with Non-Specific Liability to Substance Dependence in a Collaborative de novo Meta-Analysis of European-Ancestry Cohorts.
- Author
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Schwantes-An TH, Zhang J, Chen LS, Hartz SM, Culverhouse RC, Chen X, Coon H, Frank J, Kamens HM, Konte B, Kovanen L, Latvala A, Legrand LN, Maher BS, Melroy WE, Nelson EC, Reid MW, Robinson JD, Shen PH, Yang BZ, Andrews JA, Aveyard P, Beltcheva O, Brown SA, Cannon DS, Cichon S, Corley RP, Dahmen N, Degenhardt L, Foroud T, Gaebel W, Giegling I, Glatt SJ, Grucza RA, Hardin J, Hartmann AM, Heath AC, Herms S, Hodgkinson CA, Hoffmann P, Hops H, Huizinga D, Ising M, Johnson EO, Johnstone E, Kaneva RP, Kendler KS, Kiefer F, Kranzler HR, Krauter KS, Levran O, Lucae S, Lynskey MT, Maier W, Mann K, Martin NG, Mattheisen M, Montgomery GW, Müller-Myhsok B, Murphy MF, Neale MC, Nikolov MA, Nishita D, Nöthen MM, Nurnberger J, Partonen T, Pergadia ML, Reynolds M, Ridinger M, Rose RJ, Rouvinen-Lagerström N, Scherbaum N, Schmäl C, Soyka M, Stallings MC, Steffens M, Treutlein J, Tsuang M, Wall TL, Wodarz N, Yuferov V, Zill P, Bergen AW, Chen J, Cinciripini PM, Edenberg HJ, Ehringer MA, Ferrell RE, Gelernter J, Goldman D, Hewitt JK, Hopfer CJ, Iacono WG, Kaprio J, Kreek MJ, Kremensky IM, Madden PA, McGue M, Munafò MR, Philibert RA, Rietschel M, Roy A, Rujescu D, Saarikoski ST, Swan GE, Todorov AA, Vanyukov MM, Weiss RB, Bierut LJ, and Saccone NL
- Subjects
- Adolescent, Adult, Alleles, Case-Control Studies, Child, Cohort Studies, Gene Frequency genetics, Humans, Male, Sample Size, Genetic Association Studies, Genetic Predisposition to Disease, Polymorphism, Single Nucleotide genetics, Receptors, Opioid, mu genetics, Substance-Related Disorders genetics, White People genetics
- Abstract
The mu1 opioid receptor gene, OPRM1, has long been a high-priority candidate for human genetic studies of addiction. Because of its potential functional significance, the non-synonymous variant rs1799971 (A118G, Asn40Asp) in OPRM1 has been extensively studied, yet its role in addiction has remained unclear, with conflicting association findings. To resolve the question of what effect, if any, rs1799971 has on substance dependence risk, we conducted collaborative meta-analyses of 25 datasets with over 28,000 European-ancestry subjects. We investigated non-specific risk for "general" substance dependence, comparing cases dependent on any substance to controls who were non-dependent on all assessed substances. We also examined five specific substance dependence diagnoses: DSM-IV alcohol, opioid, cannabis, and cocaine dependence, and nicotine dependence defined by the proxy of heavy/light smoking (cigarettes-per-day >20 vs. ≤ 10). The G allele showed a modest protective effect on general substance dependence (OR = 0.90, 95% C.I. [0.83-0.97], p value = 0.0095, N = 16,908). We observed similar effects for each individual substance, although these were not statistically significant, likely because of reduced sample sizes. We conclude that rs1799971 contributes to mechanisms of addiction liability that are shared across different addictive substances. This project highlights the benefits of examining addictive behaviors collectively and the power of collaborative data sharing and meta-analyses.
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- 2016
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42. Economic hardship and biological weathering: The epigenetics of aging in a U.S. sample of black women.
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Simons RL, Lei MK, Beach SR, Philibert RA, Cutrona CE, Gibbons FX, and Barr A
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- Black or African American ethnology, Black or African American statistics & numerical data, Epigenomics, Female, Humans, Socioeconomic Factors, United States ethnology, Aging, Premature etiology, Economic Recession statistics & numerical data, Health Status
- Abstract
Background: Past research has linked low socio-economic status (SES) to inflammation, metabolic dysregulation, and various chronic and age-related diseases such as type 2 diabetes, coronary heart disease, stroke, and dementia. These studies suggest that the challenges and adversities associated with low SES may result in premature aging and increased risk of morbidity and mortality., Objective: Building upon this research, the present study investigates various avenues whereby low income might accelerate biological aging., Methods: Structural equation modeling and longitudinal data from a sample of 100 Black, middle-aged women residing in the United States was used to investigate the effect of income on a recently developed epigenetic measure of biological aging. This measure can be used as a "biological clock" to assess, at any point during adulthood, the extent to which an individual is experiencing accelerated or decelerated biological aging., Results: Low income displayed a robust association with accelerated aging that was unaffected after controlling for other SES-related factors such as education, marital status, and childhood adversity. Further, our analyses indicated that the association between income and biological aging was not explained by health-related behaviors such as diet, exercise, smoking, alcohol consumption, or having health insurance. Rather, in large measure, it was financial pressure (difficulty paying bills, buying necessities, or meeting daily expenses) that accounted for the association between low income and accelerated aging., Conclusions: These findings support the view that chronic financial pressures associated with low income exert a weathering effect that results in premature aging., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
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- 2016
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43. Parenting, Socioeconomic Status Risk, and Later Young Adult Health: Exploration of Opposing Indirect Effects via DNA Methylation.
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Beach SR, Lei MK, Brody GH, Kim S, Barton AW, Dogan MV, and Philibert RA
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- Adolescent, Adult, Child, Female, Follow-Up Studies, Humans, Male, Risk, Young Adult, Black or African American genetics, DNA Methylation genetics, Epigenesis, Genetic genetics, Health Status, Parenting, Poverty, Rural Population, Social Class
- Abstract
A sample of 398 African American youth, residing in rural counties with high poverty and unemployment, were followed from ages 11 to 19. Protective parenting was associated with better health, whereas elevated socioeconomic status (SES) risk was associated with poorer health at age 19. Genome-wide epigenetic variation assessed in young adulthood (age 19), was associated with both SES risk and protective parenting. Three categories of genes were identified whose methylation was associated with parenting, SES risk, and young adult health. Methylation was a significant mediator of the impact of parenting and SES risk on young adult health. Variation in mononuclear white blood cell types was also examined and controlled, showing that it did not account for observed effects of parenting and SES risk on health., (© 2016 The Authors. Child Development © 2016 Society for Research in Child Development, Inc.)
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- 2016
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44. Methylomic Aging as a Window onto the Influence of Lifestyle: Tobacco and Alcohol Use Alter the Rate of Biological Aging.
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Beach SR, Dogan MV, Lei MK, Cutrona CE, Gerrard M, Gibbons FX, Simons RL, Brody GH, and Philibert RA
- Abstract
Objectives: To examine the effect of the relationship between alcohol and cigarette consumption on biological aging using deoxyribonucleic acid methylation-based indices., Design: Hierarchical linear regression modeling followed by fitting of higher-order effects., Setting: Longitudinal studies of aging and the effect of psychosocial stress., Participants: Participants in two ethnically informative cohorts (n = 656 white, n = 180 black)., Measurements: Deviation of biological age from chronological age as a result of smoking and alcohol consumption., Results: Greater cigarette consumption was associated with accelerated biological aging, with strong effects evident at even low levels of exposure. In contrast, alcohol consumption was associated with a mixed effect on biological aging and pronounced nonlinear effects. At low and heavy levels of alcohol consumption, there was accelerated biological aging, whereas at intermediate levels of consumption there was a relative decelerating effect. The decelerating effects of alcohol were particularly notable at loci for which methylation increased with age., Conclusion: These data support prior epidemiological studies indicating that moderate alcohol use is associated with healthy aging, but we urge caution in interpreting these results. Conversely, smoking has strong negative effects at all levels of consumption. These results also support the use of methylomic indices as a tool for assessing the impact of lifestyle on aging., (© 2015, Copyright the Authors Journal compilation © 2015, The American Geriatrics Society.)
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- 2015
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45. Neighborhood crime and depressive symptoms among African American women: Genetic moderation and epigenetic mediation of effects.
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Lei MK, Beach SR, Simons RL, and Philibert RA
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- Adult, DNA Methylation, Female, Health Surveys, Humans, Middle Aged, Polymorphism, Genetic, Promoter Regions, Genetic, Residence Characteristics, Black or African American genetics, Crime psychology, Depression genetics, Epigenomics, Serotonin Plasma Membrane Transport Proteins genetics
- Abstract
Introduction: Social scientists have long recognized the important role that neighborhood crime can play in stress-related disease, but very little is known about potential biosocial mechanisms that may link the experience of living in high-crime neighborhoods with depression., Objective: The current study introduces an integrated model that combines neighborhood, genetic, and epigenetic factors., Methods: Hypotheses were tested with a sample of 99 African American women from the Family and Community Health Study (FACHS)., Results: Allele variants of the serotonin transporter gene (5-HTT) interact with neighborhood crime to predict depressive symptoms in a manner consonant with the differential susceptibility perspective. Furthermore, this association is mediated by DNA methylation of the promoter region of the serotonin transporter gene., Conclusion: The findings provide support for an integrated model in which changes in DNA methylation, resulting from neighborhood crime, can result in an increase or decrease in gene activity which, in turn, influences depressive symptoms., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
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- 2015
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46. Current and Future Prospects for Epigenetic Biomarkers of Substance Use Disorders.
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Andersen AM, Dogan MV, Beach SR, and Philibert RA
- Abstract
Substance abuse has an enormous impact on economic and quality of life measures throughout the world. In more developed countries, overutilization of the most common forms of substances of abuse, alcohol and tobacco, is addressed primarily through prevention of substance use initiation and secondarily through the treatment of those with substance abuse or dependence. In general, these therapeutic approaches to substance abuse are deemed effective. However, there is a broad consensus that the development of additional tools to aid diagnosis, prioritize treatment selection and monitor treatment response could have substantial impact on the effectiveness of both substance use prevention and treatment. The recent demonstrations by a number of groups that substance use exposure is associated with robust changes in DNA methylation signatures of peripheral blood cells suggests the possibility that methylation assessments of blood or saliva could find broad clinical applications. In this article, we review recent progress in epigenetic approaches to substance use assessment with a particular emphasis on smoking (and alcohol) related applications. In addition, we highlight areas, such as the epigenetics of psychostimulant, opioid and cannabis abuse, which are markedly understudied and could benefit from intensified collaborative efforts to define epigenetic biomarkers of abuse and dependence.
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- 2015
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47. Smoking, Methylation at AHRR, and Recidivism Risk in a Community Correction Sample of Individuals at High Risk for Recidivism.
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Gunter TD and Philibert RA
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- Adult, Basic Helix-Loop-Helix Transcription Factors blood, Criminals psychology, Female, Genetic Predisposition to Disease, Humans, Male, Repressor Proteins blood, Risk Factors, Smoking blood, Basic Helix-Loop-Helix Transcription Factors genetics, Criminal Behavior, DNA Methylation, Repressor Proteins genetics, Smoking genetics
- Abstract
Individuals supervised by community correction programs have a high rate of tobacco use and high frequency of tobacco dependence. As compared with supervisees without tobacco dependence, probationers and parolees with tobacco dependence were more likely to abuse other substances and report poorer health. In this sample of 374 predominantly felon and repeat offenders, at high risk for recidivism, over 95% of subjects smoked or used other tobacco products, 87% were actively smoking at the time of interview, and 70% met criteria for lifetime tobacco dependence. Seventy-four percent had DNA demethylation, defined as methylation less than 83%, at the aryl hydrocarbon receptor repressor (AHRR) residue interrogated by cg0557592 at the time of interview. Seventy-eight percent exhibited four-year recidivism. Demethylation was associated with four-year recidivism in women, but not men. These findings suggest that methylation at cg05575921 serves as a semi-quantitative measure of both recent use and lifetime burden, that community correction populations continue to smoke at high risk, that measurement of methylation may add to the identification of female offenders at risk for recidivism, and that treatments to assist in cessation efforts are desperately needed., (Copyright © 2015 John Wiley & Sons, Ltd.)
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- 2015
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48. Ethnicity and Smoking-Associated DNA Methylation Changes at HIV Co-Receptor GPR15.
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Dogan MV, Xiang J, Beach SR, Cutrona C, Gibbons FX, Simons RL, Brody GH, Stapleton JT, and Philibert RA
- Abstract
Smoking is associated with poorer health outcomes for both African and European Americans. In order to better understand whether ethnic-specific genetic variation may underlie some of these differences, we compared the smoking-associated genome-wide methylation signatures of African Americans with those of European Americans, and followed up this analysis with a focused examination of the most ethnically divergent locus, cg19859270, at the GPR15 gene. We examined the association of methylation at this locus to the rs2230344 SNP and GPR15 gene and protein expression. Consistent with prior analyses, AHRR residue cg05575921 was the most differentially methylated residue in both African Americans and European Americans. However, the second most differentially methylated locus in African Americans, cg19859270, was only modestly differentially methylated in European Americans. Interrogation of the methylation status of this CpG residue found in GPR15, a chemokine receptor involved in HIV pathogenesis, showed a significant interaction of ethnicity with smoking as well as a marginal effect of genotype at rs2230344, a neighboring non-synonymous SNP, but only among African Americans. Gene and protein expression analyses showed that demethylation at cg19859270 was associated with an increase in both mRNA and protein levels. Since GPR15 is involved in the early stages of viral replication for some HIV-1 and HIV-2 isolates, and the prevalence of HIV is increased in African Americans and smokers, these data support a possible role for GPR15 in the ethnically dependent differential prevalence of HIV.
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- 2015
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49. Developmental interplay between children's biobehavioral risk and the parenting environment from toddler to early school age: Prediction of socialization outcomes in preadolescence.
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Kochanska G, Boldt LJ, Kim S, Yoon JE, and Philibert RA
- Subjects
- Child, Child, Preschool, Female, Humans, Male, Anger physiology, Child Behavior physiology, Child Development physiology, Parent-Child Relations, Parenting psychology, Risk-Taking, Serotonin Plasma Membrane Transport Proteins genetics, Socialization
- Abstract
We followed 100 community families from toddler age to preadolescence. Each mother- and father-child dyad was observed at 25, 38, 52, 67, and 80 months (10 hr/child) to assess positive and power-assertive parenting. At age 10 (N = 82), we obtained parent- and child-reported outcome measures of children's acceptance of parental socialization: cooperation with parental monitoring, negative attitude toward substance use, internalization of adult values, and callous-unemotional tendencies. Children who carried a short serotonin transporter linked polymorphic region gene (5-HTTLPR) allele and were highly anger prone, based on anger observed in laboratory from 25 to 80 months, were classified as high in biobehavioral risk. The remaining children were classified as low in biobehavioral risk. Biobehavioral risk moderated links between parenting history and outcomes. For low-risk children, parenting measures were unrelated to outcomes. For children high in biobehavioral risk, variations in positive parenting predicted cooperation with monitoring and negative attitude toward substance use, and variations in power-assertive parenting predicted internalization of adult values and callous-unemotional tendencies. Suboptimal parenting combined with high biobehavioral risk resulted in the poorest outcomes. The effect for attitude toward substance use supported differential susceptibility: children high in biobehavioral risk who received optimal parenting had a more adaptive outcome than their low-risk peers. The remaining effects were consistent with diathesis-stress.
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- 2015
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50. The relationship between alcohol consumption, perceived stress, and CRHR1 genotype on the hypothalamic-pituitary-adrenal axis in rural African Americans.
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Obasi EM, Shirtcliff EA, Brody GH, MacKillop J, Pittman DM, Cavanagh L, and Philibert RA
- Abstract
Objective: Rurally situated African Americans suffer from stress and drug-related health disparities. Unfortunately, research on potential mechanisms that underlie this public health problem have received limited focus in the scientific literature. This study investigated the effects of perceived stress, alcohol consumption, and genotype on the hypothalamic-pituitary-adrenal (HPA) Axis., Methods: A rural sample of African American emerging adults (n = 84) completed a battery of assessments and provided six samples of salivary cortisol at wakeup, 30 min post wakeup, 90 min post wakeup, 3:00 PM, 3:30 PM, and 4:30 PM., Results: Participants with a TT genotype of the CRHR1 (rs4792887) gene tended to produce the most basal cortisol throughout the day while participants with a CC genotype produced the least amount. Increased levels of perceived stress or alcohol consumption were associated with a blunted cortisol awakening response (CAR). Moreover, the CAR was obliterated for participants who reported both higher stress and alcohol consumption., Conclusion: Perceived stress and alcohol consumption had a deleterious effect on the HPA-Axis. Furthermore, genotype predicted level of cortisol production throughout the day. These findings support the need to further investigate the relationship between stress dysregulation, drug-use vulnerability, and associated health disparities that affect this community.
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- 2015
- Full Text
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