Epigenetic aging in older people living with HIV in Eswatini: a pilot study of HIV and lifestyle factors and epigenetic aging

BACKGROUND

People living with HIV (PLHIV) on effective antiretroviral therapy are living near-normal lives. Although they are less susceptible to AIDS-related complications, they remain highly vulnerable to non-communicable diseases. In this exploratory study of older PLHIV (OPLHIV) in Eswatini, we investigated whether epigenetic aging (i.e., the residual between regressing epigenetic age on chronological age) was associated with HIV-related parameters, and whether lifestyle factors modified these relationships. We calculated epigenetic aging focusing on the Horvath, Hannum, PhenoAge and GrimAge epigenetic clocks, and a pace of biological aging biomarker (DunedinPACE) among 44 OPLHIV in Eswatini.

RESULTS

Age at HIV diagnosis was associated with Hannum epigenetic age acceleration (EAA) (β-coefficient [95% Confidence Interval]; 0.53 [0.05, 1.00], p = 0.03) and longer duration since HIV diagnosis was associated with slower Hannum EAA (- 0.53 [- 1.00, - 0.05], p = 0.03). The average daily dietary intake of fruits and vegetables was associated with DunedinPACE (0.12 [0.03, 0.22], p = 0.01). The associations of Hannum EAA with the age at HIV diagnosis and duration of time since HIV diagnosis were attenuated when the average daily intake of fruits and vegetables or physical activity were included in our models. Diet and self-perceived quality of life measures modified the relationship between CD4+ T cell counts at participant enrollment and Hannum EAA.

CONCLUSIONS

Epigenetic age is more advanced in OPLHIV in Eswatini in those diagnosed with HIV at an older age and slowed in those who have lived for a longer time with diagnosed HIV. Lifestyle and quality of life factors may differentially affect epigenetic aging in OPLHIV. To our knowledge, this is the first study to assess epigenetic aging in OPLHIV in Eswatini and one of the few in sub-Saharan Africa.

Psychosocial Stress and MicroRNA Expression Profiles in Myometrial Tissue of Women Undergoing Surgical Treatment for Uterine Fibroids

Uterine leiomyomas (fibroids) are the most common non-cancerous tumors affecting women. Psychosocial stress is associated with fibroid risk and severity. The relationship between psychosocial stress and fibroid pathogenesis may involve alterations in microRNAs (miRNAs) although this has yet to be examined. We investigated associations between two psychosocial stress measures, a composite measure of recent stressful life events and perceived social status, with expression levels of 401 miRNAs in myometrium (n = 20) and fibroids (n = 44; 20 with paired fibroid and myometrium samples) among pre-menopausal women who underwent surgery for fibroid treatment. We used linear regressions to identify psychosocial stressors associated with miRNAs, adjusting for covariates (age, body mass index, race/ethnicity, and oral contraceptive use). The association between psychosocial stressors and miRNAs was considered statistically significant at an FDR p < 0.10 and showed a monotonic response (nominal p-trend < 0.05). In the myometrium, 21 miRNAs were significantly associated with a composite measure of recent stressful events, and two miRNAs were associated with perceived social status. No fibroid miRNAs were associated with either stress measure. Pathway analyses revealed miRNA-mRNA targets were significantly enriched (FDR p < 0.05) in pathways relevant to cancer/tumor development. Of the 74 differentially expressed miRNAs between myometrium and fibroids, miR-27a-5p and miR-301b were also associated with stress exposure. Our pilot analysis suggests that psychosocial stress is associated with myometrial miRNA expression and, thus, may have a role in the pathogenesis of fibroids from healthy myometrium.

Epigenetic aging in older people living with HIV in Eswatini: a pilot study of HIV and lifestyle factors and epigenetic aging

Background

People living with HIV (PLHIV) on effective antiretroviral therapy (ART) are living near-normal lives. Although they are less susceptible to AIDS-related complications, they remain highly vulnerable to non-communicable diseases (NCD). In this exploratory study of older PLHIV (OPLHIV) in Eswatini, we investigated whether biological aging (i.e., the difference between epigenetic age and chronological age, termed 'epigenetic age acceleration [EAA]') was associated with HIV-related parameters, and whether lifestyle factors modified these relationships. We calculated EAA focusing on the second-generation epigenetic clocks, PhenoAge and GrimAge, and a pace of aging biomarker (DunedinPACE) among 44 OPLHIV in Eswatini.

Results

Among participants, the PhenoAge clock showed older epigenetic age (68 years old [63, 77]) but a younger GrimAge epigenetic age (median=56 years old [interquartile range=50, 61]) compared to the chronological age (59 years old [54, 66]). Participants diagnosed with HIV at an older age showed slower DunedinPACE (β-coefficient [95% Confidence Interval]; -0.02 [-0.04, -0.01], p=0.002) and longer duration since HIV diagnosis was associated with faster DunedinPACE (0.02 [0.01, 0.04], p=0.002). The average daily dietary intake of fruits and vegetables was associated with faster DunedinPACE (0.12 [0.03, 0.22], p=0.01) and modified the relationship between HIV status variables (number of years living with HIV since diagnosis, age at HIV diagnosis, CD4+ T cell counts) and PhenoAge EAA, and DunedinPACE.

Conclusions

Biological age is accelerated in OPLHIV in Eswatini, with those living with HIV for a longer duration at risk for faster biological aging. Lifestyle factors, especially healthier diets, may attenuate biological aging in OPLHIV. To our knowledge, this is the first study to assess biological aging in Eswatini and one of the few in sub-Saharan Africa.

Psychosocial stress and microRNA expression profiles in myometrial tissue of women undergoing surgical treatment for uterine fibroids

Uterine leiomyomas (fibroids) are the most common non-cancerous tumor affecting women. Psychosocial stress is associated with fibroid risk and severity. The relationship between psychosocial stress and fibroid pathogenesis may involve alterations in microRNAs (miRNAs) although this has yet to be examined. We investigated associations between two psychosocial stress measures, a composite measure of recent stressful life events and perceived social status, with expression levels of 401 miRNAs in myometrium (n = 20) and fibroids (n = 44; 20 matched between tissues) from pre-menopausal women who underwent surgery for fibroid treatment. We used linear regressions to identify psychosocial stressors associated with miRNAs, adjusting for covariates (age, body mass index, and race/ethnicity). Psychosocial stressors were modeled as ordinal variables and results were considered statistically significant if the overall variable significant was below false discovery threshold (FDR < 0.10) and showed a monotonic dose-response (nominal p-trend < 0.05). In the myometrium, 16 miRNAs were significantly associated with total stressful events and two miRNAs were associated with perceived social status. No fibroid miRNAs were associated with either stress measure. Pathway analyses revealed miRNA-mRNA targets were significantly enriched (FDR < 0.05) in pathways relevant to cancer/tumor development. Of the 74 differentially expressed miRNAs between myometrium and fibroids (p < 0.05), miR-27a-5p was also associated with stress exposure. Our pilot analysis suggests that psychosocial stress is associated with changes in myometrium miRNAs, and thus, plays a role in the pathogenesis of fibroids from healthy myometrium.

Stressful life events and accelerated biological aging over time in youths

Experiencing adversity in childhood and adolescence, including stressful life events (SLEs), may accelerate the pace of development, leading to adverse mental and physical health. However, most research on adverse early experiences and biological aging (BA) in youths relies on cross-sectional designs. In 171 youths followed for approximately 2 years, we examined if SLEs over follow-up predicted rate of change in two BA metrics: epigenetic age and Tanner stage. We also investigated if rate of change in BA was associated with changes in depressive symptoms over time. Youths aged 8-16 years at baseline self-reported Tanner stage and depressive symptoms at baseline and follow-up and provided saliva samples for DNA at both assessments. Horvath epigenetic age estimates were derived from DNA methylation data measured with the Illumina EPIC array. At follow-up, contextual threat interviews were administered to youths and caregivers to assess youths' experiences of past-year SLEs. Interviews were objectively coded by an independent rating team to generate a SLE impact score, reflecting the severity of all SLEs occurring over the prior year. Rate of change in BA metrics was operationalized as change in epigenetic age or Tanner stage as a function of time between assessments. Higher objective SLE impact scores over follow-up were related to a greater rate of change in epigenetic age (β = 0.21, p = .043). Additionally, among youths with lower-but not higher-Tanner stage at baseline, there was a positive association of SLE impact scores with rate of change in Tanner stage (Baseline Tanner Stage × SLE Impact Score interaction: β = - 0.21, p = .011). A greater rate of change in epigenetic age was also associated with higher depressive symptom levels at follow-up, adjusting for baseline symptoms (β = 0.15, p = .043). Associations with epigenetic age were similar, although slightly attenuated, when adjusting for epithelial (buccal) cell proportions. Whereas much research in youths has focused on severe experiences of early adversity, we demonstrate that more commonly experienced SLEs during adolescence may also contribute to accelerated BA. Further research is needed to understand the long-term consequences of changes in BA metrics for health.

Mother's childhood adversity is associated with accelerated epigenetic aging in pregnancy and in male newborns

Background

Adverse childhood experiences (ACEs) are correlated with accelerated epigenetic aging, but it is not clear whether altered epigenetic aging from childhood adversities persists into adulthood and can be transmitted to the next generation. Thus, we tested whether mothers' childhood adversity is associated with accelerated epigenetic aging during pregnancy and in their newborn offspring.

Methods

Data were from the Avon Longitudinal Study of Parents and Children (ALSPAC) sub-study, Accessible Resource for Integrated Epigenomic Studies (ARIES). Women provided retrospective self-reports during pregnancy of ACE exposure. DNA methylation was measured in mothers during pregnancy and cord blood at birth. Estimates of epigenetic age acceleration were calculated using Principal Components of Horvath, Hannum skin & blood, GrimAge, PhenoAge, and DunedinPACE epigenetic clocks for mothers; and the Knight and Bohlin cord blood clocks for newborns. Associations between a cumulative maternal ACE score and epigenetic age acceleration were estimated using linear regression models, adjusting for maternal age at pregnancy, smoking during pregnancy, education, and pre-pregnancy BMI. Models for offspring were stratified by sex and additionally adjusted for gestation age.

Results

Mothers' total ACE score was positively associated with accelerated maternal PhenoAge and GrimAge. In newborn offspring, mothers' total ACE score was positively associated with accelerated epigenetic aging in males using the Bohlin clock, but not in females using either epigenetic clock. We found male offsprings' epigenetic age was accelerated in those born to mothers exposed to neglect using the Knight clock; and parental substance abuse using the Bohlin clock.

Conclusion

Our results show that mothers' ACE exposure is associated with DNAm age acceleration in male offspring, supporting the notion that DNAm age could be a marker of intergenerational biological embedding of mothers' childhood adversity. This is consistent with findings on vulnerability of male fetuses to environmental insults.

Maternal DNA methylation signatures of arsenic exposure is associated with adult offspring insulin resistance in the Strong Heart Study

Exposure to low to moderate arsenic (As) levels has been associated with type 2 diabetes (T2D) and other chronic diseases in American Indian communities. Prenatal exposure to As may also increase the risk for T2D in adulthood, and maternal As has been associated with adult offspring metabolic health measurements. We hypothesized that T2D-related outcomes in adult offspring born to women exposed to low to moderate As can be evaluated utilizing a maternally-derived molecular biosignature of As exposure. Herein, we evaluated the association of maternal DNA methylation with incident T2D and insulin resistance (Homeostatic model assessment of insulin resistance [HOMA2-IR]) in adult offspring. For DNA methylation, we used 20 differentially methylated cytosine-guanine dinucleotides (CpG) previously associated with the sum of inorganic and methylated As species (ΣAs) in urine in the Strong Heart Study (SHS). Of these 20 CpGs, we found six CpGs nominally associated (p < 0.05) with HOMA2-IR in a fully adjusted model that included clinically relevant covariates and offspring adiposity measurements; a similar model that adjusted instead for maternal adiposity measurements found three CpGs nominally associated with HOMA2-IR, two of which overlapped the offspring adiposity model. After adjusting for multiple comparisons, cg03036214 remained associated with HOMA2-IR (q < 0.10) in the offspring adiposity model. The odds ratio of incident T2D increased with an increase in maternal DNA methylation at one HOMA2-IR associated CpG in the model adjusting for offspring adiposity, cg12116137, whereas adjusting for maternal adiposity had a minimal effect on the association. Our data suggests offspring adiposity, rather than maternal adiposity, potentially influences the effects of maternal DNAm signatures on offspring metabolic health parameters. Here, we have presented evidence supporting a role for epigenetic biosignatures of maternal As exposure as a potential biomarker for evaluating risk of T2D-related outcomes in offspring later in life.

Examining the immunoepigenetic-gut microbiome axis in the context of self-esteem among Native Hawaiians and other Pacific Islanders

Introduction: Native Hawaiian and other Pacific Islander (NHPI) populations experience higher rates of immunometabolic diseases compared to other racial-ethnic groups in Hawaii. As annual NHPI mortality rates for suicide and type 2 diabetes mellitus (T2DM) exceed those of the state as a whole, understanding the social and biological mechanisms underlying these disparities are urgently needed to enable preventive strategies. Methods: A community-based approach was used to investigate the immunoepigenetic-gut microbiome axis in an NHPI-enriched cohort of Oahu residents (N = 68). Self-esteem (SE) data was collected using a modified Rosenberg self-esteem (SE) assessment as a proxy measure for mental wellbeing in consideration for cultural competency. T2DM status was evaluated using point-of-care A1c (%) tests. Stool samples were collected for 16s-based metagenomic sequencing analyses. Plasma from blood samples were isolated by density-gradient centrifugation. Peripheral blood mononuclear cells (PBMCs) were collected from the same samples and enriched for monocytes using negative selection techniques. Flow-cytometry was used for immunoprofiling assays. Monocyte DNA was extracted for Illumina EPIC array-based methylation analysis. Results: Compared to individuals with normal SE (NSE), those with low SE (LSE) exhibited significantly higher plasma concentrations (pg/ml) of proinflammatory cytokines IL-8 (p = 0.051) and TNF-α (p = 0.011). Metagenomic analysis revealed that the relative abundance (%) of specific gut bacteria significantly differed between SE groups - some of which directly correlated with SE scores. Gene ontology analysis revealed that 104 significantly differentially methylated loci (DML) between SE groups were preferentially located at genes involved in immunometabolic processes. Horvath clock analyses indicated epigenetic age (Epi-Age) deceleration in individuals with LSE and acceleration in individuals with NSE (p = 0.042), yet was not reproduced by other clocks. Discussion: These data reveal novel differences in the immunoepigenetic-gut microbiome axis with respect to SE, warranting further investigation into its relationship to brain activity and mental health in NHPI. Unexpected results from Epi-Age analyses warrant further investigation into the relationship between biological age and disparate health outcomes among the NHPI population. The modifiable component of epigenetic processes and the gut microbiome makes this axis an attractive target for potential therapeutics, biomarker discovery, and novel prevention strategies.

Shifts in the immunoepigenomic landscape of monocytes in response to a diabetes-specific social support intervention: a pilot study among Native Hawaiian adults with diabetes

BACKGROUND

Native Hawaiians are disproportionately affected by type 2 diabetes mellitus (DM), a chronic metabolic, non-communicable disease characterized by hyperglycemia and systemic inflammation. Unrelenting systemic inflammation  frequently leads to a cascade of multiple comorbidities associated with DM, including cardiovascular disease, microvascular complications, and renal dysfunction. Yet few studies have examined the link between chronic inflammation at a cellular level and its relationship to standard DM therapies such as diabetes-specific lifestyle and social support education, well recognized as the cornerstone of clinical standards of diabetes care. This pilot study was initiated to explore the association of monocyte inflammation using epigenetic, immunologic, and clinical measures following a 3-month diabetes-specific social support program among high-risk Native Hawaiian adults with DM.

RESULTS

From a sample of 16 Native Hawaiian adults with DM, monocytes enriched from peripheral blood mononuclear cells (PBMCs) of 8 individuals were randomly selected for epigenomic analysis. Using the Illumina HumanMethylation450 BeadChip microarray, 1,061 differentially methylated loci (DML) were identified in monocytes of participants at baseline and 3 months following a DM-specific social support program (DM-SSP). Gene ontology analysis showed that these DML were enriched within genes involved in immune, metabolic, and cardiometabolic pathways, a subset of which were also significantly differentially expressed. Ex vivo analysis of immune function showed improvement post-DM-SSP compared with baseline, characterized by attenuated interleukin 1β and IL-6 secretion from monocytes. Altered cytokine secretion in response to the DM-SSP was significantly associated with changes in the methylation and gene expression states of immune-related genes in monocytes between intervention time points.

CONCLUSIONS

Our pilot study provides preliminary evidence of changes to inflammatory monocyte activity, potentially driven by epigenetic modifications, 3 months following a DM-specific SSP intervention. These novel alterations in the trajectory of monocyte inflammatory states were identified at loci that regulate transcription of immune and metabolic genes in high-risk Native Hawaiians with DM, suggesting a relationship between improvements in psychosocial behaviors and shifts in the immunoepigenetic patterns following a diabetes-specific SSP. Further research is warranted to investigate how social support influences systemic inflammation via immunoepigenetic modifications in chronic inflammatory diseases such as DM.

Stress and spirituality in relation to HPA axis gene methylation among US Black women: results from the Black Women's Health Study and the Study on Stress, Spirituality and Health

Background: Few epigenetics studies have been conducted within the Black community to examine the impact of diverse psychosocial stressors and resources for resiliency on the stress pathway (hypothalamus-pituitary-adrenal axis). Methods: Among 1000 participants from the Black Women's Health Study, associations between ten psychosocial stressors and DNA methylation (DNAm) of four stress-related genes (NR3C1, HSDB1, HSD11B2 and FKBP5) were tested. Whether religiosity or spirituality (R/S) significantly modified these stress-DNAm associations was also assessed. Results: Associations were found for several stressors with DNAm of individual CpG loci and average DNAm levels across each gene, but no associations remained significant after false discovery rate (FDR) correction. Several R/S variables appeared to modify the relationship between two stressors and DNAm, but no identified interaction remained significant after FDR correction. Conclusion: There is limited evidence for a strong signal between stress and DNAm of hypothalamus-pituitary-adrenal axis genes in this general population cohort of US Black women.