DOES SOCIAL STATUS PREDICT INDIVIDUAL DIFFERENCES IN HYPOTHALAMIC-PITUITARY-ADRENOCORTICAL ACTIVITY?

Lack of control and threats to social standing, whether evoked by acute or chronic stressors or reflected in symptoms of depression, are salient correlates of hypothalamic-pituitary-adrenal (HPA) activity. These conditions are also reminiscent of low social status (subordination), which has long been associated with HPA activity in non-human primates. In humans, interpersonal dominance and socioeconomic indicators are often used interchangeably to describe social status, but have distinctly different referents. Here, we examined the relationship of these two status constructs with three indices of HPA functioning [Cortisol Awakening Response (CAR), diurnal decline in cortisol (slope), and cortisol Area Under the Curve (AUC)] in 488 employed, healthy volunteers (30-54 yrs; M=43; 53% F; 83% White). Measurements of salivary cortisol were taken on five occasions during three workdays and one non-workday. Cortisol indices were averaged over work days, and non-workday indices were analyzed separately. A trait measure of dominance was calculated using items from the NEO Personality Inventory-Revised, and socioeconomic status (SES) was indexed to participants’ annual income, years of education, and occupational grade. Trait dominance and SES were entered separately as predictors of each HPA index in hierarchical linear regressions adjusted for age, sex, and race. A three variable composite of SES did not associate with cortisol, but an index restricted to income and occupation did. Both low trait dominance and low income and occupation derived SES associated with a larger workday CAR (β= -.13, p=.02 and β= -.17, p=.007) and flatter workday diurnal slope (β= -.11, p=.03and β= -.16, p=.002), but were unrelated to AUC or any non-workday indices. Trait dominance and SES were only weakly correlated (r=.08, p=.09), and findings persisted when the two predictors were entered together in regression models. These results show two largely independent conceptualizations of social status in humans related to metrics of cortisol activity

Sleep duration partially accounts for race differences in diurnal cortisol dynamics

Objective: Emerging research demonstrates race differences in diurnal cortisol slope, an indicator of hypothalamic-pituitary-adrenocortical (HPA)-axis functioning associated with morbidity and mortality, with African Americans showing flatter diurnal slopes than their White counterparts. Sleep characteristics are associated with both race and with HPA-axis functioning. The present report examines whether sleep duration may account for race differences in cortisol dynamics. Method: Participants were 424 employed African American and White adults (mean age = 42.8 years, 84.2% White, 53.6% female) with no cardiovascular disease (Adult Health and Behavior Project—Phase 2 [AHAB-II] cohort, University of Pittsburgh). Cortisol slope was calculated using 4 salivary cortisol readings, averaged over each of 4 days. Demographic (age, sex), psychosocial (socioeconomic status [SES], affect, discrimination), and health behaviors (smoking, alcohol use, physical activity) variables were used as covariates, and sleep (self-report and accelerometry) was also assessed. Results: African Americans had flatter slopes than Whites (F(1, 411) = 10.45, B = .02, p = .001) in models adjusting for demographic, psychosocial, and health behavior covariates. Shorter actigraphy-assessed total sleep time was a second significant predictor of flatter cortisol slopes (F(1, 411) = 25.27, B = −.0002, p \u3c .0001). Total sleep time partially accounted for the relationship between race and diurnal slope [confidence interval = .05 (lower = .014, upper .04)]. Conclusions: African Americans have flatter diurnal cortisol slopes than their White counterparts, an effect that may be partially attributable to race differences in nightly sleep duration. Sleep parameters should be considered in further research on race and cortisol. (PsycINFO Database Record (c) 2017 APA, all rights reserved

Sleep duration partially accounts for race differences in diurnal cortisol dynamics

Objective: Emerging research demonstrates race differences in diurnal cortisol slope, an indicator of hypothalamic-pituitary-adrenocortical (HPA)-axis functioning associated with morbidity and mortality, with African Americans showing flatter diurnal slopes than their White counterparts. Sleep characteristics are associated with both race and with HPA-axis functioning. The present report examines whether sleep duration may account for race differences in cortisol dynamics. Method: Participants were 424 employed African American and White adults (mean age = 42.8 years, 84.2% White, 53.6% female) with no cardiovascular disease (Adult Health and Behavior Project—Phase 2 [AHAB-II] cohort, University of Pittsburgh). Cortisol slope was calculated using 4 salivary cortisol readings, averaged over each of 4 days. Demographic (age, sex), psychosocial (socioeconomic status [SES], affect, discrimination), and health behaviors (smoking, alcohol use, physical activity) variables were used as covariates, and sleep (self-report and accelerometry) was also assessed. Results: African Americans had flatter slopes than Whites (F(1, 411) = 10.45, B = .02, p = .001) in models adjusting for demographic, psychosocial, and health behavior covariates. Shorter actigraphy-assessed total sleep time was a second significant predictor of flatter cortisol slopes (F(1, 411) = 25.27, B = −.0002, p \u3c .0001). Total sleep time partially accounted for the relationship between race and diurnal slope [confidence interval = .05 (lower = .014, upper .04)]. Conclusions: African Americans have flatter diurnal cortisol slopes than their White counterparts, an effect that may be partially attributable to race differences in nightly sleep duration. Sleep parameters should be considered in further research on race and cortisol. (PsycINFO Database Record (c) 2017 APA, all rights reserved

Trait positive and negative emotionality differentially associate withdiurnal cortisol activity

Inter-individual variability in metrics of hypothalamic-pituitary-adrenocortical (HPA) activity, such asthe slope of the diurnal decline in cortisol, cortisol awakening response (CAR), and total cortisol out-put, have been found to associate inversely with trait ratings of extraversion and positive affect (E/PA)and positively with neuroticism and negative affect (N/NA) in some, but not all, investigations. Theseinconsistencies may partly reflect varied intensity of cortisol sampling among studies and reliance onself-rated traits, which are subject to reporting biases and limitations of introspection. Here, we furtherexamined dispositional correlates of HPA activity in 490 healthy, employed midlife volunteers (M age = 43years; 54% Female; 86% white). Trait ratings were requested from participants and 2 participant-electedinformants using the Positive and Negative Affect Schedule (PANAS) and Extraversion and Neuroticismdimensions of NEO personality inventories. CAR was assessed as percent increase in cortisol levels fromawakening to 30 min after awakening; and the diurnal slope and total output of cortisol [Area Underthe Curve (AUC)] were determined from cortisol measurements taken at awakening, +4 and +9 h later,and bedtime, across 3 workdays. Structural equation modeling was used to estimate multi-informantE/PA and N/NA factors. We used 3 days of measurement as indicators to model each of the three latentcortisol factors (slope, CAR, and AUC). With the two latent emotionality and three latent cortisol indicesincluded there was good fit to the data ( 2(200)= 278.38, p = 0.0002; RMSEA = 0.028, 90% CI = 0.02–0.04;CFI/TLI = 0.97/0.96; SRMR = 0.04). After controlling for covariates (age, sex, race), results showed higherlatent E/PA associated with a steeper diurnal slope (Standardized ˇ = −0.19, p = 0.02) and smaller CAR(Standardized ˇ = −0.26, p = 0.004), whereas N/NA did not associate with any cortisol metric (Standard-ized ˇ’s = −0.12 to 0.13, p’s = 0.10 to 0.53). These findings suggest that positive emotionality may be moreclosely associated with indices of diurnal cortisol release than negative emotionality

Trait positive and negative emotionality differentially associate withdiurnal cortisol activity

Inter-individual variability in metrics of hypothalamic-pituitary-adrenocortical (HPA) activity, such asthe slope of the diurnal decline in cortisol, cortisol awakening response (CAR), and total cortisol out-put, have been found to associate inversely with trait ratings of extraversion and positive affect (E/PA)and positively with neuroticism and negative affect (N/NA) in some, but not all, investigations. Theseinconsistencies may partly reflect varied intensity of cortisol sampling among studies and reliance onself-rated traits, which are subject to reporting biases and limitations of introspection. Here, we furtherexamined dispositional correlates of HPA activity in 490 healthy, employed midlife volunteers (M age = 43years; 54% Female; 86% white). Trait ratings were requested from participants and 2 participant-electedinformants using the Positive and Negative Affect Schedule (PANAS) and Extraversion and Neuroticismdimensions of NEO personality inventories. CAR was assessed as percent increase in cortisol levels fromawakening to 30 min after awakening; and the diurnal slope and total output of cortisol [Area Underthe Curve (AUC)] were determined from cortisol measurements taken at awakening, +4 and +9 h later,and bedtime, across 3 workdays. Structural equation modeling was used to estimate multi-informantE/PA and N/NA factors. We used 3 days of measurement as indicators to model each of the three latentcortisol factors (slope, CAR, and AUC). With the two latent emotionality and three latent cortisol indicesincluded there was good fit to the data ( 2(200)= 278.38, p = 0.0002; RMSEA = 0.028, 90% CI = 0.02–0.04;CFI/TLI = 0.97/0.96; SRMR = 0.04). After controlling for covariates (age, sex, race), results showed higherlatent E/PA associated with a steeper diurnal slope (Standardized ˇ = −0.19, p = 0.02) and smaller CAR(Standardized ˇ = −0.26, p = 0.004), whereas N/NA did not associate with any cortisol metric (Standard-ized ˇ’s = −0.12 to 0.13, p’s = 0.10 to 0.53). These findings suggest that positive emotionality may be moreclosely associated with indices of diurnal cortisol release than negative emotionality

The Genomic Distribution and Function of Histone Variant HTZ-1 during C. elegans Embryogenesis

In all eukaryotes, histone variants are incorporated into a subset of nucleosomes to create functionally specialized regions of chromatin. One such variant, H2A.Z, replaces histone H2A and is required for development and viability in all animals tested to date. However, the function of H2A.Z in development remains unclear. Here, we use ChIP-chip, genetic mutation, RNAi, and immunofluorescence microscopy to interrogate the function of H2A.Z (HTZ-1) during embryogenesis in Caenorhabditis elegans, a key model of metazoan development. We find that HTZ-1 is expressed in every cell of the developing embryo and is essential for normal development. The sites of HTZ-1 incorporation during embryogenesis reveal a genome wrought by developmental processes. HTZ-1 is incorporated upstream of 23% of C. elegans genes. While these genes tend to be required for development and occupied by RNA polymerase II, HTZ-1 incorporation does not specify a stereotypic transcription program. The data also provide evidence for unexpectedly widespread independent regulation of genes within operons during development; in 37% of operons, HTZ-1 is incorporated upstream of internally encoded genes. Fewer sites of HTZ-1 incorporation occur on the X chromosome relative to autosomes, which our data suggest is due to a paucity of developmentally important genes on X, rather than a direct function for HTZ-1 in dosage compensation. Our experiments indicate that HTZ-1 functions in establishing or maintaining an essential chromatin state at promoters regulated dynamically during C. elegans embryogenesis

Impact of health behaviors on prenatal maternal stress

Previous studies find prenatal stress to relate to negative health in mothers and their children. Health behaviors such as exercise, proper nutrition, and relaxation have been found to reduce stress in non-pregnant populations, yet few studies have investigated the effect of these behaviors on prenatal stress. The current study examined the impact of exercise, nutrition, and relaxation on perceived stress, anxiety, and cortisol reactivity to a stress task in pregnant women. We hypothesized that women who exercised, had better eating habits, and engaged in relaxation would have reduced perceived stress, anxiety and more adaptive cortisol responses. Our results suggest an adaptive effect of exercise, and maladaptive effect of fat consumption on prenatal cortisol responses, but no association between health behaviors and perceived stress or anxiety. These findings contribute to our understanding of the relationship between health behaviors and stress during pregnancy, and may be useful for prenatal health interventions

Factors Associated with Prenatal Health Behaviors among Low-Income, Ethnic Minority Women

Less than one-third of pregnant women in the U.S. meet prenatal nutrition, exercise, and stress management health behavior guidelines. Low rates of these prenatal health behaviors have been especially observed among low-income, ethnic minority women, placing them and their infants at a disproportionally higher risk for health complications. Yet, few studies have identified factors associated with these prenatal health behaviors in this population. This study examined whether certain demographic (e.g., ethnicity) and psychosocial characteristics (i.e., coping, stress, pregnancy-specific stress, and depression) were associated with prenatal nutrition (i.e., high-fat food and fruit and vegetable intake), exercise, and stress management health behaviors in 100 low-income, pregnant women (39% African American, 30% foreign-born Latinas, 15% U.S.-born Latinas, 10% non-Hispanic white, and 6% Asian American/Pacific Islander) in southern California using an embedded, mixed-methods, cross-sectional design. Results demonstrated that ethnic minority women who experienced more stress and used more maladaptive coping strategies (e.g., avoidance) were particularly at risk of consuming more high-fat foods and engaging in less exercise and stress management during pregnancy. Qualitative responses revealed women’s experiences with these prenatal health behaviors. These findings highlight the need for interventions and collaborative care models that target psychosocial factors in order to optimize prenatal health behaviors and health outcomes among ethnic minority women