Development of glucocorticoid resistance over one year among mothers of children newly diagnosed with cancer

Exploring the interplay between stress mediators and skin microbiota in shaping age-related hallmarks: A review

Psychological stress is a major contributing factor to several health problems (e.g., depression, cardiovascular disease). Around 35 % of the world's population suffers from it, including younger generations. Physiologically, stress manifests through neuroendocrine pathways (Hypothalamic-Pituitary-Adrenal (HPA) axis and Sympathetic-Adrenal-Medullary (SAM) system) which culminate in the production of stress mediators like cortisol, epinephrine and norepinephrine. Stress and its mediators have been associated to body aging, through molecular mechanisms such as telomere attrition, mitochondrial dysfunction, cellular senescence, chronic inflammation, and dysbiosis, among others. Regarding its impact in the skin, stress impacts its structural integrity and physiological function. Despite this review focusing on several hallmarks of aging, emphasis was placed on skin microbiota dysbiosis. In this line, several studies, comprising different age groups, demographic contexts and body sites, have reported skin microbiota alterations associated with aging, and some effects of stress mediators on skin microbiota have also been reviewed in this paper. From a different perspective, since it is not a "traditional" stress mediator, oxytocin, a cortisol antagonist, has been related to glucorticoids inhibition and to display positive effects on cellular aging. This hormone dysregulation has been associated to psychological issues such as depression, whereas its upregulation has been linked to positive social interaction.

Childhood trauma and hair cortisol response over the year following onset of a chronic life event stressor

OBJECTIVE

Childhood trauma may contribute to poor lifelong health in part through programming of the HPA-axis response to future life stressors. To date, empirical evidence shows an association of childhood trauma with dysregulation of the HPA-axis and blunted cortisol reactivity to acute stressors. Here, we conduct an initial examination of childhood trauma as a moderator of changes over time in perceived stress levels and HPA-axis response to a major chronic stressor in adulthood.

METHODS

Participants were 83 maternal caregivers of children newly diagnosed with cancer who completed the Childhood Trauma Questionnaire (CTQ), and who, over the year following their child's cancer diagnosis, had hair samples collected up to 7 times for the assessment of cortisol and completed monthly measures of perceived stress.

RESULTS

CTQ scores were in the expected range for a community sample and associated with changes in perceived stress and cortisol concentration over time (γ =.003, p =.002; γ = -.0004, p =.008, respectively) independently of age, education, treatment intensity and randomization to stress management intervention. Maternal caregivers who endorsed lower childhood trauma showed a steeper decline in perceived stress and a larger increase in cortisol levels across the year than caregivers who recalled more childhood trauma.

CONCLUSIONS

Findings extend animal models and studies that examine cortisol reactivity to acute stressors and suggest that childhood trauma may program a phenotype that is more psychologically reactive but shows a blunted HPA-axis response to chronic stress. While adaptive in the short-term, this early life programming may incur long-term costs for health. Further work is warranted to examine this possibility.

Social Determinants of Health in Cardio-Oncology: Multi-Level Strategies to Overcome Disparities in Care: JACC: CardioOncology State-of-the-Art Review

Addressing the need for more equitable cardio-oncology care requires attention to existing disparities in cardio-oncologic disease prevention and outcomes. This is particularly important among those affected by adverse social determinants of health (SDOH). The intricate relationship of SDOH, cancer diagnosis, and outcomes from cardiotoxicities associated with oncologic therapies is influenced by sociopolitical, economic, and cultural factors. Furthermore, mechanisms in cell signaling and epigenetic effects on gene expression link adverse SDOH to cancer and the CVD-related complications of oncologic therapies. To mitigate these disparities, a multifaceted strategy is needed that includes attention to health care access, policy, and community engagement for improved disease screening and management. Interdisciplinary teams must also promote cultural humility and competency and leverage new health technology to foster collaboration in addressing the impact of adverse SDOH in cardio-oncologic outcomes.

Exploratory Review of the Takotsubo Syndrome and the Possible Role of the Psychosocial Stress Response and Inflammaging

Takotsubo syndrome (TTS) is a cardiomyopathy that clinically presents as a transient and reversible left ventricular wall motion abnormality (LVWMA). Recovery can occur spontaneously within hours or weeks. Studies have shown that it mainly affects older people. In particular, there is a higher prevalence in postmenopausal women. Physical and emotional stress factors are widely discussed and generally recognized triggers. In addition, the hypothalamic-pituitary-adrenal (HPA) axis and the associated glucocorticoid-dependent negative feedback play an important role in the resulting immune response. This review aims to highlight the unstudied aspects of the trigger factors of TTS. The focus is on emotional stress/chronic unpredictable mild stress (CUMS), which is influenced by estrogen concentration and noradrenaline, for example, and can lead to changes in the behavioral, hormonal, and autonomic systems. Age- and gender-specific aspects, as well as psychological effects, must also be considered. We hypothesize that this leads to a stronger corticosteroid response and altered feedback of the HPA axis. This may trigger proinflammatory markers and thus immunosuppression, inflammaging, and sympathetic overactivation, which contributes significantly to the development of TTS. The aim is to highlight the importance of CUMS and psychological triggers as risk factors and to make an exploratory proposal based on the new knowledge. Based on the imbalance between the sympathetic and parasympathetic nervous systems, transcutaneous vagus nerve stimulation (tVNS) is presented as a possible new therapeutic approach.

Psychosocial experiences of caring by family caregivers of patients living with prostate cancer in a teaching hospital: A descriptive phenomenological study

AIM

This study explored the psychosocial experience of caregiving on the family caregiver of patients with prostate cancer in the Cape Coast metropolis of Ghana.

DESIGN

A descriptive phenomenological study was conducted through in-depth face-to-face semi-structured interviews. Twelve family caregivers of prostate cancer patients were selected through purposive sampling. Interviews were conducted until data saturation. All interviews were taped, transcribed verbatim and analysed thematically.

RESULTS

The family caregiver's psychosocial experience associated with caregiving uncovered two significant themes with 13 sub-themes. 'Psychological impact' emerged as the first central theme, with anxiety, care as an obligation and feelings of inadequacy, hopelessness, uncertainty, denial and concealment as the sub-themes. The second central theme was 'Social impact' with sexual concerns, role adjustment, loss of livelihood, turmoil and reduced leisure activities emerging as sub-themes.

CONCLUSION

The findings demonstrated that caring significantly impacts the psychological and social well-being of the caregivers of prostate cancer patients. Therefore, there is a need for holistic assessment to include the psychosocial well-being of family caregivers to improve quality of life. Therefore, psychiatric nurses support family caregivers through education and psychosocial interventions to improve their quality of life and enable them to care for their loved ones more effectively.

Stress-induced biological aging: A review and guide for research priorities

Exposure to chronic adverse conditions, and the resultant activation of the neurobiological response cascade, has been associated with an increased risk of early onset of age-related disease and, recently, with an older biological age. This body of research has led to the hypothesis that exposure to stressful life experiences, when occurring repeatedly or over a prolonged period, may accelerate the rate at which the body ages. The mechanisms through which chronic psychosocial stress influences distinct biological aging pathways to alter rates of aging likely involve multiple layers in the physiological-molecular network. In this review, we integrate research using animal, human, and in vitro models to begin to delineate the distinct pathways through which chronic psychosocial stress may impact biological aging, as well as the neuroendocrine mediators (i.e., norepinephrine, epinephrine, and glucocorticoids) that may drive these effects. Findings highlight key connections between stress and aging, namely cellular metabolic activity, DNA damage, telomere length, cellular senescence, and inflammatory response patterns. We conclude with a guiding framework and conceptual model that outlines the most promising biological pathways by which chronic adverse conditions could accelerate aging and point to key missing gaps in knowledge where future research could best answer these pressing questions.

Chronic stress increases transcriptomic indicators of biological aging in mouse bone marrow leukocytes

Research with animals and humans has demonstrated that chronic stress exposure can impact key biological aging pathways such as inflammation and DNA damage, suggesting a mechanism through which stress may increase risk for age-related disease. However, it is less clear whether these effects extend to other hallmarks of the aging process, such as cellular senescence. Male SCID mice were exposed to 14 days of restraint stress, with (n ​= ​6) or without (n ​= ​10) propranolol administration, or a non-stress control condition (n ​= ​10). Normal femoral bone marrow leukocytes were isolated from engrafted leukemia cells that had been injected prior to the stressor, as the mice were also under a cancer challenge. We performed whole genome transcriptional profiling to assess indicators of biological aging: cell stress, DNA damage repair, cellular senescence markers p16^INK4a and p21, and the pro-inflammatory senescence-associated secretory phenotype (SASP). ANCOVAs that adjusted for tumor load and Fisher's pairwise comparisons revealed that stressed mice had enhanced p16^INK4a (p ​= ​.02) and p21 (p ​= ​.004), lower DNA damage repair (p ​< ​.001), and higher SASP (p ​= ​.03) gene expression than control mice. Stressed mice also showed up-regulated beta-adrenergic (CREB) and inflammatory (NF-кB, AP-1) and down-regulated cell stress (Nrf2) transcription factor activity relative to control mice (ps ​< ​.01). Propranolol reversed CREB and Nrf2 activity (ps ​< ​.03). Findings suggest that chronic stress exposure can impact several key biological aging pathways within bone marrow leukocytes and these effects may be partially mediated by sympathetic beta-adrenergic receptor activation.

Immunological and psychosocial functioning in parents of children with cancer

PURPOSE

Research has shown that parents of children with cancer exhibit an altered immune profile compared to parents of healthy children, reflective of increased susceptibility to illness. These parents are also at risk for poorer psychosocial outcomes and quality of life. The current study compares peripheral blood cell analyses and psychosocial self-reports from parents of children being treated for cancer (n = 21) to parents of healthy children (n = 30).

METHODS

A blood sample was drawn from parents to analyze immune profiles. Parents also completed the Perceived Stress Scale (PSS), Medical Outcomes Study Short Form-36 (MOS), and Patient-Reported Outcomes Measurement Information System Short Form v1.0 Emotional Distress-Anxiety 8a, and Emotional Distress-Depression 8a (PROMIS). Mann-Whitney U tests and independent samples t-tests were conducted to examine differences in outcomes between parent groups.

RESULTS

Parents of children with cancer exhibited higher monocyte percentages in their peripheral blood compared to peers with healthy children. Parents of children with cancer also reported poorer psychosocial outcomes: higher perceived stress, higher anxiety and depression symptoms, more role disability resulting from emotional problems, poorer general and mental health, and poorer social functioning.

CONCLUSION

These findings support research that has shown a direct effect of chronic stress on the immune system. Symptoms reported by parents of children with cancer indicate unmet psychosocial needs that could potentially affect long-term health. Given the central role of parents in their children's cancer care, it is compelling to address and work to improve parent immunological and psychosocial well-being.

Social Determinants of Cardiovascular Disease

Social determinants of health (SDoH), which encompass the economic, social, environmental, and psychosocial factors that influence health, play a significant role in the development of cardiovascular disease (CVD) risk factors as well as CVD morbidity and mortality. The COVID-19 pandemic and the current social justice movement sparked by the death of George Floyd have laid bare long-existing health inequities in our society driven by SDoH. Despite a recent focus on these structural drivers of health disparities, the impact of SDoH on cardiovascular health and CVD outcomes remains understudied and incompletely understood. To further investigate the mechanisms connecting SDoH and CVD, and ultimately design targeted and effective interventions, it is important to foster interdisciplinary efforts that incorporate translational, epidemiological, and clinical research in examining SDoH-CVD relationships. This review aims to facilitate research coordination and intervention development by providing an evidence-based framework for SDoH rooted in the lived experiences of marginalized populations. Our framework highlights critical structural/socioeconomic, environmental, and psychosocial factors most strongly associated with CVD and explores several of the underlying biologic mechanisms connecting SDoH to CVD pathogenesis, including excess stress hormones, inflammation, immune cell function, and cellular aging. We present landmark studies and recent findings about SDoH in our framework, with careful consideration of the constructs and measures utilized. Finally, we provide a roadmap for future SDoH research focused on individual, clinical, and policy approaches directed towards developing multilevel community-engaged interventions to promote cardiovascular health.

Stress-Related Inflammation and Social Withdrawal in Mothers of a Child With Cancer: A 1-Year Follow-Up Study

OBJECTIVE

Acute inflammation-induced sickness behavior involves changes in social behavior that are believed to promote recovery. Whether chronic inflammation can influence social behaviors in ways that promote recovery is unknown. In a sample of mothers of a child with cancer, this report explores the relationship between inflammation that accompanies the stress of diagnosis and changes in social network, cancer-related stress, and inflammation across 1 year. Three hypotheses tested whether a) initial levels of stress associate with initial levels of inflammation, b) initial levels of inflammation predict social network changes over time, and c) social network changes over time buffer changes in stress and inflammation over time.

METHODS

Cancer-related stress (Impact of Events Scale), social network (social roles and contacts from the Social Network Inventory), and systemic inflammation (circulating interleukin [IL]-6) were assessed in 120 mothers three times after their child's cancer diagnosis: after diagnosis (T1), 6-month follow-up (T2), and 12-month follow-up (T3).

RESULTS

Consistent with predictions, greater cancer-related stress after diagnosis (T1) was associated with higher IL-6 after diagnosis (T1; b = 0.014, standard error [SE] = 0.01, p = .008). In turn, higher IL-6 after diagnosis (T1) was associated with a decrease in social roles over time (T1 ➔ T3; B = -0.030, SE = 0.01, p = .041). Finally, dropping social roles over time (T1 ➔ T3) was associated with decreases in cancer-related stress (B = 25.44, SE = 12.31, p = .039) and slower increases in IL-6 (B = 1.06, SE = 0.52, p = .040) over time.

CONCLUSIONS

This study provides a first indication that chronic stress-related systemic inflammation may predict changes in social behavior that associate with stress recovery and slower increases in inflammation in the year after a major life stressor.

Epigenetics and the International Classification of Functioning, Disability and Health Model: Bridging Nature, Nurture, and Patient-Centered Population Health

Epigenetic processes enable environmental inputs such as diet, exercise, and health behaviors to reversibly tag DNA with chemical "marks" that increase or decrease the expression of an individual's genetic template. Over time, epigenetic adaptations enable the effects of healthy or unhealthy stresses to become stably expressed in the tissue of an organism, with important consequences for health and disease. New research indicates that seemingly non-biological factors such as social stress, poverty, and childhood hardship initiate epigenetic adaptations in gene pathways that govern inflammation and immunity, two of the greatest contributors to chronic diseases such as diabetes and obesity. Epigenetic processes therefore provide a biological bridge between the genome-an individual's genetic inheritance-and the Social Determinants of Health-the conditions in which they are born, grow, live, work, and age. This Perspective paper argues that physical therapy clinicians, researchers, and educators can use the theoretical framework provided by the International Classification of Functioning, Disability, and Health (ICF model) to harmonize new discoveries from both public health research and medically focused genomic research. The ICF model likewise captures the essential role played by physical activity and exercise, which initiate powerful and widespread epigenetic adaptations that promote health and functioning. In this proposed framework, epigenetic processes transduce the effects of the social determinants of health and behaviors such as exercise into stable biological adaptations that affect an individual's daily activities and their participation in social roles. By harmonizing "nature" and "nurture," physical therapists can approach patient care with a more integrated perspective, capitalizing on novel discoveries in precision medicine, rehabilitation science, and in population-level research. As the experts in physical activity and exercise, physical therapists are ideally positioned to drive progress in the new era of patient-centered population health care.

Glucocorticoid resistance and β2-adrenergic receptor signaling pathways promote peripheral pro-inflammatory conditions associated with chronic psychological stress: A systematic review across species

Activation of the HPA-axis and SNS are widely accepted to link chronic stress with elevated levels of peripheral pro-inflammatory markers in blood. Yet, empirical evidence showing that peripheral levels of glucocorticoids and/or catecholamines mediate this effect is equivocal. Recent attention has turned to the possibility that cellular sensitivity to these ligands may contribute to inflammatory mediators that accompany chronic stress. We review current evidence for the association of chronic stress with glucocorticoid receptor (GR) and β-adrenergic receptor (β-AR) signaling sensitivity. Across 15 mouse, 7 primate, and 19 human studies, we found that chronic stress reliably associates with downregulation in cellular GR sensitivity, alterations in intracellular β-AR signaling, and upregulation in pro-inflammatory biomarkers in peripheral blood. We also present evidence that alterations in GR and β-AR signaling may be specific to myeloid progenitor cells such that stress-related signaling promotes release of cells that are inherently less sensitive to glucocorticoids and differentially sensitive to catecholamines. Our findings have broad implications for understanding mechanisms by which chronic stress may contribute to pro-inflammatory phenotypes.

The long noncoding RNA HOTAIRM1 controlled by AML1 enhances glucocorticoid resistance by activating RHOA/ROCK1 pathway through suppressing ARHGAP18

Acquired resistance to glucocorticoids (GCs) is an obstacle to the effective treatment of leukemia, but the molecular mechanisms of steroid insensitivity have not been fully elucidated. In this study, we established an acquired GC-resistant leukemia cell model and found a long noncoding RNA, HOTAIRM1, was overexpressed in the resistant cells by transcriptional profiling, and was higher expressed in patients with poor prognosis. The whole-genome-binding sites of HOTAIRM1 were determined by ChIRP-seq (chromatin isolation by RNA purification combined with sequencing) analysis. Further study determined that HOTAIRM1 bound to the transcriptional inhibitory region of ARHGAP18 and repressed the expression of ARHGAP18, which led to the increase of RHOA/ROCK1 signaling pathway and promoted GC resistance through antiapoptosis of leukemia cells. The inhibition of ROCK1 in GC-resistant cells could restore GCs responsiveness. In addition, HOTAIRM1 could also act as a protein sequester to prevent transcription factor AML1(acute myeloid leukemia 1) from binding to the regulatory region of ARHGAP18 by interacting with AML1. At last, we also proved AML1 could directly activate the expression of HOTAIRM1 through binding to the promoter of HOTAIRM1, which enriched the knowledge on the regulation of lncRNAs. This study revealed epigenetic causes of glucocorticoid resistance from the perspective of lncRNA, and laid a foundation for the optimization of glucocorticoid-based leukemia treatment strategy in clinic.

Mindfulness-Based Stress Reduction Buffers Glucocorticoid Resistance Among Older Adults: A Randomized Controlled Trial

OBJECTIVE

Mindfulness interventions have been effective for improving a range of health outcomes; however, pathways underlying these effects remain unclear. Inflammatory processes may play a role, possibly through increased resistance of immune cells to the anti-inflammatory effects of glucocorticoids (i.e., glucocorticoid resistance, or GCR). Here, we conducted an initial examination of whether mindfulness training mitigates GCR among lonely older adults.

METHODS

Lonely older adults (65-85 years; n = 190) were randomly assigned to an 8-week Mindfulness-Based Stress Reduction (MBSR) or a matched Health Enhancement Program (HEP). Whole blood drawn before and after the intervention and at 3-month follow-up was incubated with endotoxin and varying concentrations of dexamethasone, and interleukin-6 production was assessed using enzyme-linked immunosorbent assay. GCR was assessed as the concentration of dexamethasone required to decrease the stimulated interleukin-6 response by 50% (half maximal inhibitory concentration), with higher concentrations indicating greater GCR. Mixed-effects linear models tested time (pre, post, follow-up) by condition (MBSR versus HEP) effects.

RESULTS

There was no overall time by condition effect on GCR across all time points. However, a significant time by condition effect was observed from preintervention to postintervention (d = 0.29), such that MBSR buffered increases in GCR observed in the HEP group. Although MBSR showed small, nonsignificant reductions in GCR from preintervention to 3-month follow-up, group differences were not maintained at the 3-month follow-up (d = 0.10).

CONCLUSIONS

Results suggest that MBSR may protect against declines in the sensitivity of immune cells to the anti-inflammatory effects of glucocorticoids among at-risk lonely older adults and show value in studying this biological mechanism in future trials.Trial Registration: Clinical Trials identifier NCT02888600.

Efficacy of a Stress Management Intervention for Mothers of Children with Cancer

OBJECTIVE

Mothers of children with cancer confront life stress that can impact their psychological and physical health and, in turn, the health of the family. Recommendations advocate preemptive stress-management interventions; however, few studies have investigated their efficacy. Here, we report results of a parallel randomized pilot trial examining health benefits of a stress management intervention designed to teach coping skills.

METHODS

One hundred twenty mothers (age 36 ± 8 years) of children newly diagnosed with cancer were randomized to a 12-session stress management intervention (n = 60) or usual care (n = 60). Sessions took place in the inpatient or outpatient setting of a children's hospital. Primary outcome variables included psychological function and physical health assessed preintervention and postintervention and at 6-month follow-up (∼12 months postdiagnosis).

RESULTS

Enrollment, retention, and satisfaction data supported feasibility and acceptability. Latent change score models showed the intervention reduced perceived stress (d = -0.37, p = 0.03), anxiety symptoms (ds = -0.38 and -0.56, ps < .03) and, a nonsignificant effect for depressive symptoms (d = -0.29, p = .11) across the 6 months following diagnosis. Intervention participants also endorsed fewer depressive symptoms than controls ∼12 months after diagnosis. The intervention improved stress management skills, which associated with the psychological benefits of participation. There were no intervention-related changes in perceived health or markers of inflammation.

CONCLUSION

Intervention-related improvements in stress management skills may result in better psychological health in the face of caring for a child with cancer.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02022449.

Biological Consequences of Psychological Distress in Caregivers of Children with Autism Spectrum Disorder and its Potential Relevance to Other Chronic Diseases Including Cancer

Purpose of Review

Caregivers of children with a chronic illness are a neglected group in medical research and patient care, and are frequently confronted with chronic psychological distress. The biological consequences of this chronic distress are unclear but highly relevant, as these caregivers have a lifelong task in caring for their child. In this review, the authors specifically describe caregiver distress related to autism spectrum disorder (ASD), but the review may be relevant to other chronic diseases, including cancer.

Recent Findings

Epidemiological evidence illustrates the increased mortality risk in caregivers of children with ASD although some individual factors appear to diminish these risks. Biological studies demonstrate that caregiver distress can lead to dysregulation of the hypothalamic-pituitary-adrenal-axis, a pro-inflammatory state of the immune and central nervous system, and gut microbiome imbalance.

Summary

Caregivers of children with a chronic illness like ASD deserve more health-related attention with respect to their psychological and physical well-being. Such attention would benefit individual caregivers, as well as their children, as both are highly interconnected. Structural psychological and physical screening of caregivers can be considered.

Association Among Glucocorticoid Receptor Sensitivity, Fatigue, and Inflammation in Patients With Head and Neck Cancer

OBJECTIVE

Fatigued cancer patients often have high peripheral inflammation; however, the biological mechanisms of this association remain unclear. We examined whether decreased sensitivity of immune cells to the anti-inflammatory effects of glucocorticoids may contribute to inflammation and fatigue in head and neck cancer (HNC) patients during treatment.

METHODS

HNC patients without distant metastasis and with curative intent (n = 77) were studied 1 week before intensity-modulated radiotherapy (IMRT) and 1 month after IMRT. At each time point, fatigue was measured by the Multidimensional Fatigue Inventory-20 along with plasma inflammation markers and glucocorticoid receptor (GR) sensitivity as determined by in vitro dexamethasone suppression of lipopolysaccharide-induced interleukin 6. Linear regression models were used.

RESULTS

In contrast to our hypothesis, GR sensitivity increased during treatment; however, increased fatigue was associated with a lesser increase in GR sensitivity from baseline to 1 month after IMRT (unstandardized estimate = 4.07, p = .02). This effect was more prominent in human papillomavirus-unrelated HNCs (unstandardized estimate = 8.22, p = .002). Lower increases in GR sensitivity were also associated with increased inflammation at 1 month after IMRT as represented by C-reactive protein, interleukin 6, and tumor necrosis factor α. Addition of inflammation markers to models of GR sensitivity predicting fatigue indicated that these inflammation markers were stronger predictors of fatigue than GR sensitivity.

CONCLUSIONS

Lower increases in GR sensitivity during HNC treatment were significantly predictive of increased fatigue and inflammation markers. Inflammation markers in turn predicted fatigue above and beyond levels of GR sensitivity. Our findings indicate that HNC patients with cancer-related fatigue may exhibit a decreased capacity for glucocorticoids to regulate inflammatory processes, as evidenced by a lower increase in GR sensitivity. Larger studies are necessary to verify the findings.

Mitochondrial respiratory capacity modulates LPS-induced inflammatory signatures in human blood

Mitochondria modulate inflammatory processes in various model organisms, but it is unclear how much mitochondria regulate immune responses in human blood leukocytes. Here, we examine the effect of i) experimental perturbations of mitochondrial respiratory chain function, and ii) baseline inter-individual variation in leukocyte mitochondrial energy production capacity on stimulated cytokine release and glucocorticoid (GC) sensitivity. In a first cohort, whole blood from 20 healthy women and men was stimulated with increasing concentrations of the immune agonist lipopolysaccharide (LPS). Four inhibitors of mitochondrial respiratory chain Complexes I, III, IV, and V were used (LPS + Mito-Inhibitors) to acutely perturb mitochondrial function, GC sensitivity was quantified using the GC-mimetic dexamethasone (DEX) (LPS + DEX), and the resultant cytokine signatures mapped with a 20-cytokine array. Inhibiting mitochondrial respiration caused large inter-individual differences in LPS-stimulated IL-6 reactivity (Cohen's d = 0.72) and TNF-α (d = 1.55) but only minor alteration in EC50-based LPS sensitivity (d = 0.21). Specifically, inhibiting mitochondrial Complex IV potentiated LPS-induced IL-6 levels by 13%, but inhibited TNF-α induction by 72%, indicating mitochondrial regulation of the IL-6/TNF-α ratio. As expected, DEX treatment suppressed multiple LPS-induced pro-inflammatory cytokines (IFN-γ, IL-6, IL-8, IL-1β, .TNF-α) by >85% and increased the anti-inflammatory cytokine IL-10 by 80%. Inhibiting Complex I potentiated DEX suppression of IL-6 by a further 12% (d = 0.73), indicating partial mitochondrial modulation of glucocorticoid sensitivity. Finally, to examine if intrinsic mitochondrial respiratory capacity may explain a portion of immune reactivity differences across individuals, we measured biochemical respiratory chain enzyme activities and mitochondrial DNA copy number in isolated peripheral blood mononuclear cells (PBMCs) from a second cohort of 44 healthy individuals in parallel with LPS-stimulated IL-6 and TNF-α response. Respiratory chain .function, particularly Complex IV activity, was positively correlated with LPS-stimulated IL-6 levels (r = 0.45, p = 0.002). Overall, these data provide preliminary evidence that mitochondrial behavior modulates LPS-induced inflammatory cytokine signatures in human blood.

Metabolites and metabolic pathways associated with glucocorticoid resistance in pregnant African-American women

Glucocorticoid resistance (GR) is associated with exposure to chronic stress and an increased risk of metabolic and inflammatory disorders in both animal and human populations. Studies on ethnic disparities highlight the African-American (AA) population as having a high propensity to both GR and chronic stress exposure. Glucocorticoids and inflammation play a very important role in pregnancy outcome and fetal development. To date, however, the metabolites and metabolic pathways associated with GR during pregnancy have not been identified, obscuring the mechanisms by which adverse health consequences arise, and thus impeding targeted therapeutic intervention. The objective of this study was to perform untargeted high-resolution metabolomics (HRM) profiling on 273 pregnant AA women, to identify metabolites and metabolic pathways associated with GR during the first trimester of pregnancy and to evaluate their cross-sectional association with birth outcomes and psychosocial variables related to chronic stress exposure. For this study, GR was determined by the concentration of dexamethasone required for 50% inhibition (Dex IC50) of the cytokine tumor-necrosis factor alpha (TNF-alpha) release in vitro in response to a standard dose of lipopolysaccharide. The results for Metabolome-Wide Association Studies (MWAS) and pathway enrichment analysis for serum metabolic associations with Dex IC50, showed energy (nicotinamide and TCA cycle), amino acid, and glycosphingolipid metabolism as top altered pathways. Bioinformatic analysis showed that GR, as indicated by elevated Dex IC50 in the pregnant women, was associated with increased inflammatory metabolites, oxidative stress related metabolites, increased demand for functional amino acids to support growth and development, and disruption in energy-related metabolites. If confirmed in future studies, targeting these physiologically significant metabolites and metabolic pathways may lead to future assessment and intervention strategies to prevent inflammatory and metabolic complications observed in pregnant populations.

•

GR is associated with chronic stress and is a risk factor for adverse health outcomes, especially among African Americans.

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Metabolites and metabolic pathways associated with GR relate to energy production, amino acid metabolism, and inflammation.

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Findings provide a foundation for future studies investigating risk factors in this health disparity population.

Minimally-invasive methods for examining biological changes in response to chronic stress: A scoping review

BACKGROUND

Nurse researchers are increasingly interested in incorporating biological indicators related to chronic stress, or repeated or constant exposure to psychological stressors. Minimally invasive collection methods may improve access to vulnerable populations.

OBJECTIVE

To map biological indicators measured through minimally invasive methods investigating biological changes in response to chronic stress.

DESIGN, DATA SOURCES, AND METHODS

The paper seeks to answer two questions: What are the characteristics of the minimally-invasive methods used to measure the biological correlates of chronic stress? What are the limitations regarding the use of the minimally-invasive methods and/or biological indicators identified above? Authors completed a scoping review following guidelines from the Joanna Briggs Institute Manual and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for Scoping Reviews. A literature search was completed in PubMed, PsycINFO, and Scopus. 2518 articles were screened and 145 studies were included. Data were extracted using a standardized extraction tool, compiled, and coded.

RESULTS

Studies included minimally-invasive methods to measure the hypothalamic-adrenal-pituitary axis (N = 173), immune and inflammatory markers (N = 118), and adult neurogenesis (N = 6). Cortisol was most frequently measured (N = 136), usually in saliva (N = 86). Studies included a variety of limitations for the methods and indicators, including concerns about timing and accuracy of collection, frequency of sampling, and controlling for acute stressors.

CONCLUSIONS

Nurse researchers have access to many minimally-invasive methods to measure altered biological processes related to chronic stress. A gap identified by this review is the paucity of minimally-invasive methods for investigating neurogenesis; the measurement of brain derived neurotrophic factor in plasma is a distal proxy and further research is needed to test the response of peripheral levels to psychosocial stress interventions. Additionally, while this scoping review allows nurse researchers to consider possible biological indicators to include in their research, future research is still needed on some of the basic premises of stress research, including agreement on the conceptualization of chronic stress.

Racial discrimination and leukocyte glucocorticoid sensitivity: Implications for birth timing

RATIONALE

Psychological stress-induced cortisol elevations appear to contribute to preterm birth. Yet, some studies suggest that the biological ramifications of racial discrimination-associated stress are unique and may involve development of decreased glucocorticoid sensitivity despite normalized cortisol levels.

OBJECTIVE

In this study, we examined the effects of racial discrimination on maternal cortisol output, leukocyte glucocorticoid sensitivity, and the degree of correspondence between cortisol levels and birth timing in an African American cohort.

METHOD

A generally healthy prospective cohort was enrolled at 28-32 weeks gestation (n = 91). The Experiences of Discrimination scale was administered, whole blood collected, and plasma cortisol levels, cytokine levels, and leukocyte counts quantified for examination of patterns of endogenous feedback.

RESULTS

Racial discrimination in the mid-tertile was associated with greater maternal cortisol levels than the bottom tertile among women reporting internalizing responses (b* = 0.68, p = 0.001). Decreased leukocyte glucocorticoid sensitivity was witnessed at greater frequencies of experiences of racial discrimination, as evidenced by decreased correspondence between maternal cortisol levels and plasma IL-8 levels, monocyte counts, and lymphocyte counts (p values ≤ 0.043). The association between maternal cortisol levels and birth timing differed by discrimination tertile (p values ≤ 0.005), with greater cortisol levels predictive of earlier birth among women without (b* = -0.59, p < 0.001) but not with racial discrimination (ps ≥ 0.497).

CONCLUSION

We provide novel evidence of decreased glucocorticoid sensitivity at increasing frequency of exposure to racial discrimination. Our findings suggest that the biology of preterm birth may depend upon racial discriminatory exposures, favoring pathways dependent upon glucocorticoid-induced increases in leukocyte tissue surveillance versus glucocorticoid resistance-associated inflammatory aberrations at increasing levels of exposure. Precision approaches to prenatal care are sorely needed to combat preterm birth, particularly among African American women, with efforts dependent upon further research examining the pathways contributing to the syndrome dependent upon the totality of an individual's exposures.