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Objectives The aim of the study was to: (1) Identify (early in pregnancy) psychosocial and stress-related factors that predict risk of spontaneous preterm birth (PTB, gestational age Study Design This is a prospective cohort study. Relative risk (RR) analyses investigated association between individual factors and PTB. Machine learning-based interdependency analysis (IDPA) identified factor clusters, strength, and direction of association with PTB. A nonlinear model based on support vector machines was built for predicting PTB and identifying factors that most strongly predicted PTB. Results Higher levels of deleterious factors were associated with increased RR for PTB: General anxiety (RR = 8.9; 95% confidence interval [CI] = 2.0,39.6), pain (RR = 5.7; CI = 1.7,17.0); tiredness/fatigue (RR = 3.7; CI = 1.09,13.5); perceived risk of birth complications (RR = 4; CI = 1.6,10.01); self-rated health current (RR = 2.6; CI = 1.0,6.7) and previous 3 years (RR = 2.9; CI = 1.1,7.7); and divorce (RR = 2.9; CI = 1.1,7.8). Lower levels of protective factors were also associated with increased RR for PTB: low happiness (RR = 9.1; CI = 1.25,71.5); low support from parents/siblings (RR = 3.5; CI = 0.9,12.9), and father-of-baby (RR = 3; CI = 1.1,9.9). These factors were also components of the clusters identified by the IDPA: perceived risk of birth complications (p Conclusion These findings represent an important step toward identifying key factors, which can be assessed rapidly before/after conception, to predict risk of PTB, and perhaps other adverse pregnancy outcomes. Quantifying these factors, before, or early in pregnancy, could identify women at risk of delivering preterm, pinpoint mechanisms/targets for intervention, and facilitate the development of interventions to prevent PTB. Key Points

The authors highlight, from a firsthand perspective, Bruce S. McEwen's seminal influence on the field of stress neurobiology and beyond, and how these investigations have yielded important insights, principles and critical questions that continue to guide stress research today. Featured are discussion of: 1) the important inverted-U relationship between stress/glucocorticoids and optimal physiological function, 2) stress adaptation and the role of adaptive stress responses, 3) mechanisms by which the short-term stress response promotes heightened immune function and immunity, and 4) the far reaching impact of the theoretical framework of allostasis and allostatic load-concepts that have created new bridges between stress physiology, biomedical sciences, health psychology and sociology.

Increased inflammation is reported in Major Depressive Disorder (MDD), which may be more pronounced in suicidal subjects. Vitamin D deficiency may drive this pro-inflammatory state due to vitamin D's anti-inflammatory effects.We quantified plasma 25-hydroxyvitamin D (25(OH)D) and inflammatory markers interleukin (IL)-6 and tumor necrosis factor (TNF)-α, and other inflammatory indices, neutrophil-to-lymphocyte ratio (NLR) and white blood cell count (WBC) in 48 un-medicated MDD subjects (n = 17 with mild-to-moderate suicidal ideation [SI]) and 54 controls. IL-6 and TNF-α were combined into a composite inflammation score.There were no significant differences in 25(OH)D levels between MDD and controls (p = 0.24) or between MDD with and without SI (p = 0.61). However, 25(OH)D was negatively correlated with all measured inflammatory markers; these correlations were stronger in MDD subjects, and particularly in those with SI. MDD status significantly moderated the relationships between 25(OH)D and NLR (p = 0.03), and 25(OH)D and WBC (p 0.05), and SI significantly moderated the relationship between 25(OH)D and NLR (p = 0.03).The study was cross-sectional, thereby limiting causal inference, and had a small sample size. Only seventeen of the MDD subjects had SI.While 25(OH)D levels did not significantly differ in MDD vs. controls, or in MDD with or without SI, lower 25(OH)D was associated with indices of immune activation in MDD, especially in cases with SI. Although our findings do not address causality, they are consistent with findings that relatively low 25(OH)D levels in MDD are associated with a pro-inflammatory state.

While studies have speculated that immune function may play a role in how water, sanitation, hygiene, and nutritional (N+WSH) interventions may individually impact child growth and development, the combined effects of these interventions on immune system development are unknown. Here, we report on a trial in rural Bangladesh, where we cluster-randomized pregnant women into control and N+WSH arms. Among the birth cohort, we quantified plasma IL-1β, IL-6, TNF-α, IL-2, IL-12p70, IFN-γ, IL-4, IL-5, IL-13, IL-17A, IL-21, IL-10, and GM-CSF at ages 14 and 28 months. Cytokine ratios were included as prespecified outcomes to examine the net inflammatory environment. We assessed 704 children. After one year, TNF-α/IL-10, IL-12/IL-10, and IL-17A/IL-10 ratios were lower in the intervention group compared to the control group (mean difference: -0.12 to -0.19, p

Background:Previously, we demonstrated that a water, sanitation, handwashing, and nutritional intervention improved linear growth and was unexpectedly associated with shortened childhood telomere length (TL) (Lin et al., 2017). Here, we assessed the association between TL and growth.Methods:We measured relative TL in whole blood from 713 children. We reported differences between the 10th percentile and 90th percentile of TL or change in TL distribution using generalized additive models, adjusted for potential confounders.Results:In cross-sectional analyses, long TL was associated with a higher length-for-age Z score at age 1 year (0.23 SD adjusted difference in length-for-age Z score [95% CI 0.05, 0.42; FDR-corrected p-value = 0.01]). TL was not associated with other outcomes.Conclusions:Consistent with the metabolic telomere attrition hypothesis, our previous trial findings support an adaptive role for telomere attrition, whereby active TL regulation is employed as a strategy to address ‘emergency states’ with increased energy requirements such as rapid growth during the first year of life. Although short periods of active telomere attrition may be essential to promote growth, this study suggests that a longer overall initial TL setting in the first 2 years of life could signal increased resilience against future telomere erosion events and healthy growth trajectories.Funding:Funded by the Bill and Melinda Gates Foundation.Clinical trial number:NCT01590095

Although several reports have documented heightened systemic inflammation in posttraumatic stress disorder (PTSD), few studies have assessed whether inflammatory markers serve as prospective biomarkers for PTSD risk. The present study aimed to characterize whether peripheral immune factors measured in blood samples collected in an emergency department immediately after trauma exposure would predict later chronic development of PTSD.Participants (N=505) were recruited from a hospital emergency department and underwent a 1.5-hour assessment. Blood samples were drawn, on average, about 3 hours after trauma exposure. Follow-up assessments were conducted 1, 3, 6, and 12 months after trauma exposure. Latent growth mixture modeling was used to identify classes of PTSD symptom trajectories.Three distinct classes of PTSD symptom trajectories were identified: chronic (N=28), resilient (N=160), and recovery (N=85). Multivariate analyses of covariance revealed a significant multivariate main effect of PTSD symptom trajectory class membership on proinflammatory cytokines. Univariate analyses showed a significant main effect of trajectory class membership on plasma concentrations of proinflammatory tumor necrosis factor α (TNFα) and interferon-γ (IFNγ). Concentrations of proinflammatory TNFα and IFNγ were significantly lower in individuals in the chronic PTSD class compared with those in the recovery and resilient classes. There were no significant differences in interleukin (IL) 1β and IL-6 concentrations by PTSD symptom trajectory class. Anti-inflammatory and other cytokines, as well as chemokines and growth factor concentrations, were not associated with development of chronic PTSD.Overall, the study findings suggest that assessing the proinflammatory immune response to trauma exposure immediately after trauma exposure, in the emergency department, may help identify individuals most at risk for developing chronic PTSD in the aftermath of trauma.

In this issue, David Jessop presents a commentary entitled The Power of Positive Stress and a Research Roadmap. I appreciate our Editor in Chief, James Herman’s invitation to provide a “commentary ...

Prior work has linked meditation practice to improvements in interference control. However, the mechanisms underlying these improvements are relatively unknown. In the context of meditation training, improvements in interference control could result either from increases in controlled attention to goal-relevant stimuli, or from reductions in automatic capture by goal-irrelevant stimuli. Moreover, few studies have linked training-related changes in attention to physiological processes, such as inflammatory activity, that are thought to influence cognitive function. This study addresses these gaps by examining associations between cognitive performance and cytokines in the context of an intensive meditation retreat. Participants were randomly assigned to complete 3 months of meditation training first, or to serve as waiting-list controls. The waitlist control participants then later completed a separate 3-month training intervention. We assessed participants’ interference control with a flanker task and used computational modeling to derive component processes of controlled and automatic attention. We also collected blood samples at the beginning, middle, and end of training to quantify changes in cytokine activity. Participants who completed training evidenced better controlled attention than waitlist controls during the first retreat intervention, and controls showed significant improvements in controlled attention when they completed their own, second retreat. Importantly, inflammatory activity was inversely associated with controlled attention during both interventions. Our results suggest that practice of concentration meditation influences interference control by enhancing controlled attention to goal-relevant task elements, and that inflammatory activity relates to individual differences in controlled attention.

Objective Increased inflammation and oxidative stress have been shown in Major Depressive Disorder (MDD), although there is significant heterogeneity across studies. Whether markers of inflammation and oxidative stress are associated with antidepressant treatment response in MDD is currently unclear. The goals of the present study are to investigate markers of inflammation and oxidative stress in unmedicated MDD subjects and controls and test the relationship between these markers and antidepressant response in MDD subjects. Methods Interleukin (IL)-6, tumor necrosis factor (TNF)-α, C-reactive protein, F2-isoprostanes, 8-OH 2-deoxyguanosine (8-OHdG), glutathione peroxidase, glutathione, and vitamin C were quantified in blood samples from 50 unmedicated MDD subjects and 55 healthy controls. Depression symptom severity was rated with the 17-item Hamilton Depression Rating Scale (HDRS). All subjects were somatically healthy and free from medications that could interfere with inflammation and oxidative stress markers. A subgroup of 22 MDD subjects underwent open-label selective serotonin reuptake inhibitor (SSRI) antidepressant treatment for eight weeks, after which blood sampling and the HDRS were repeated. Antidepressant treatment “response” was defined as ≥50% decrease in HDRS ratings over 8 weeks of treatment. Results After controlling for the effects of age, sex, body mass index and smoking, MDD subjects had significantly higher levels of IL-6 (p < 0.001), TNF-α (p < 0.001), 8-OHdG (p = 0.018), and F2-isoprostanes (p = 0.012). Compared to Responders, Non-responders to SSRI antidepressant treatment had higher levels of F2-isoprostanes at baseline (p = 0.006), and after eight weeks of treatment (p = 0.031). Non-responders showed a significant increase in 8-OHdG over the course of treatment (p = 0.021), whereas Responders showed a significant decrease in IL-6 over the course of treatment (p = 0.019). Conclusion Our results are in line with previous reports of increased levels of markers of inflammation and oxidative stress in MDD. Moreover, poorer antidepressant treatment response was related to higher baseline levels of the major oxidative stress marker, F2-isoprostanes, in vivo. Further, antidepressant response was associated with changes in oxidative (8-OHdG) and inflammatory (IL-6) markers.

Introduction Several lines of evidence indicate that increased inflammation is associated with Post-Traumatic Stress Disorder (PTSD). We have previously reported that peripheral inflammatory markers are significantly higher in combat-exposed veterans with than without PTSD. This study was designed to replicate these findings in a new study cohort using the same population and recruitment strategies. Methods Sixty-one male war veterans (31 PTSD and 30 control subjects) were included in this replication study. Levels of Interleukin-6, Tumor Necrosis Factor-alpha, Gamma interferon, and high-sensitivity C-reactive protein were quantified in blood samples. A standardized “total pro-inflammatory score” was calculated to limit the number of statistical comparisons. The Clinician Administered PTSD Scale (CAPS) rating scale was used to assess PTSD symptom severity. Results PTSD subjects had significantly higher total pro-inflammatory scores compared to non-PTSD subjects in unadjusted analysis (Cohen’s d = 0.75, p = 0.005) as well as after adjusting for potentially confounding effects of age, BMI, smoking, and potentially interfering medications and somatic co-morbidities (p = 0.023). There were no significant correlations between inflammatory markers and severity of symptoms within the PTSD group. Conclusions We replicated, in a new sample, our previous finding of increased inflammatory markers in combat-exposed PTSD subjects compared to combat-exposed non-PTSD controls. These findings strongly add to the growing literature suggesting that immune activation may be an important aspect of PTSD pathophysiology, although not directly correlated with current PTSD symptom levels in the PTSD group.

Women are at higher risk for developing posttraumatic stress disorder (PTSD) compared to men, yet little is known about the biological contributors to this sex difference. One possible mechanism is differential immunological and neuroendocrine responses to traumatic stress exposure. In the current prospective study, we aimed to identify whether sex is indirectly associated with the probability of developing nonremitting PTSD through pro-inflammatory markers and whether steroid hormone concentrations influence this effect. Female ( n = 179) and male ( n = 197) trauma survivors were recruited from an emergency department and completed clinical assessment within 24 h and blood samples within ∼three hours of trauma exposure. Pro-inflammatory cytokines (IL-6, IL-1[Formula: see text], TNF, IFNγ), and steroid hormone (estradiol, testosterone, progesterone, cortisol) concentrations were quantified in plasma. Compared to men, women had a higher probability of developing nonremitting PTSD after trauma ( p = 0.04), had lower pro-inflammatory cytokines and testosterone ( p’ s

Racial discrimination has been linked to allostatic load (i.e., cumulative biological stress) among African American women. Coping is a central component of the stress response process. However, limited attention has been given to psychosocial processes involved in the stress response—critical for understanding biological pathways to health—in studies examining racial discrimination as a social determinant of health. We examined whether the superwoman schema (SWS), a multidimensional culture-specific framework characterizing psychosocial responses to stress among AA women, modifies the association between racial discrimination and allostatic load. We used purposive sampling to recruit a community sample of African American women ages 30–50 from five San Francisco Bay Area counties (n = 208). Path analysis was used to test for interactions while accounting for the covariance among SWS subscales using both linear and quadratic models. Significant interactions were observed between racial discrimination and four of the five SWS subscales. Feeling obligated to present an image of strength and an obligation to suppress emotions were each protective whereas feeling an intense motivation to succeed and feeling an obligation to help others exacerbated the health risk associated with experiencing racial discrimination. Our findings affirm the need to consider individual variability in coping and potentially other psychosocial processes involved in the stress response process; and offer several insights that may help elucidate the mechanisms by which racial discrimination gets “under the skin”.

Chronic psychological stress is associated with accelerated biological aging, immune dysfunction, and premature morbidity and mortality. Changes in the relative proportions of T cell subpopulations are thought to be a characteristic of immunological aging; however, understanding of whether these changes are associated with chronic psychological stress is incomplete. This study investigated associations between chronic caregiving stress and distributions of T cell phenotypes in a sample of high stress mothers of children with Autism Spectrum Disorder (caregivers; n = 91) and low stress mothers of neurotypical children (controls; n = 88). Immune markers assessed were naive (CD45RA + CD62L+), central memory (CD45RA-CD62L+), and effector memory (CD45RA-CD62L-) CD4+ and CD8+ T cells. We also examined the ratio of effector to naive (E:N) CD4+ and CD8+ T cells. In models adjusted for age, body mass index, race/ethnicity, and antidepressant use, caregivers displayed higher percentages of effector memory CD8+ and CD4+ T cells as well as lower percentages of naive CD8+ T cells and central memory CD8+ and CD4+ T cells compared to controls. Caregivers also displayed significantly higher E:N ratios for both CD4+ and CD8+ T cells. These findings were also independent of cytomegalovirus infection status. Furthermore, higher parental stress, across both groups, was related to several immune parameters. These findings provide preliminary evidence that chronic parental caregiving stress is associated with changes in relative proportions of T cell subpopulations that are consistent with accelerated immunological aging.

Summary Inflammation has been involved in the pathophysiology and treatment response of major depressive disorder (MDD). Plasma cytokine profiles of 171 treatment-naive MDD patients (none of the MDD patients received an adequate trial of antidepressants or evidence-based psychotherapy) and 64 healthy controls (HCs) were obtained. MDD patients exhibited elevated concentrations of 18 anti- and proinflammatory markers and decreased concentrations of 6 cytokines. Increased inflammasome protein expression was observed in MDD patients, indicative of an activated inflammatory response. The plasma of MDD patients was immunosuppressive on healthy donor peripheral blood mononuclear cells, inducing reduced activation of monocytes/dendritic cells and B cells and reduced T cell memory. Comparison between 33 non-responders and 71 responders at baseline and 12 weeks revealed that after treatment, anti-inflammatory cytokine levels increase in both groups, whereas 5 proinflammatory cytokine levels were stabilized in responders, but continued to increase in non-responders. MDD patients exhibit remodeling of their inflammatory landscape.

The range of psychosocial stress factors/processes (eg, chronic stress, distress states, coping, social adversity) were reviewed as they relate to immune variables in cancer along with studies of psychosocial interventions on these stress processes and immune measures in cancer populations. The review includes molecular, cellular, and clinical research specifically examining the effects of stress processes and stress-management interventions on immune variables (eg, cellular immune function, inflammation), which may or may not be changing directly in response to the cancer or its treatment. Basic psychoneuroimmunologic research on stress processes (using animal or cellular/tumor models) provides leads for investigating biobehavioral processes that may underlie the associations reported to date. The development of theoretically driven and empirically supported stress-management interventions may provide important adjuncts to clinical cancer care going forward.

Our group has proposed that in contrast to chronic stress that can have harmful effects, the short-term (fight-or-flight) stress response (lasting for minutes to hours) is nature's fundamental survival mechanism that enhances protection and performance under conditions involving threat/challenge/opportunity. Short-term stress enhances innate/primary, adaptive/secondary, vaccine-induced, and anti-tumor immune responses, and post-surgical recovery. Mechanisms and mediators include stress hormones, dendritic cell, neutrophil, macrophage, and lymphocyte trafficking/function and local/systemic chemokine and cytokine production. Short-term stress may also enhance mental/cognitive and physical performance through effects on brain, musculo-skeletal, and cardiovascular function, reappraisal of threat/anxiety, and training-induced stress-optimization. Therefore, short-term stress psychology/physiology could be harnessed to enhance immuno-protection, as well as mental and physical performance. This review aims to provide a conceptual framework and targets for further investigation of mechanisms and conditions under which the protective/adaptive aspects of short-term stress/exercise can be optimized/harnessed, and for developing pharmacological/biobehavioral interventions to enhance health/healing, and mental/cognitive/physical performance.

Psychological distress, which can begin with cancer diagnosis and continue with treatment, is linked with circadian and endocrine disruption. In turn, circadian/endocrine factors are potent modulators of cancer progression. We hypothesized that circadian rest-activity rhythm disruption, distress, and diurnal cortisol rhythms would be associated with biomarkers of tumor progression in the peripheral blood of women awaiting breast cancer surgery. Breast cancer patients (n=43) provided actigraphic data on rest-activity rhythm, cancer-specific distress (IES, POMS), saliva samples for assessment of diurnal cortisol rhythm, cortisol awakening response (CAR), and diurnal mean. Ten potential markers of tumor progression were quantified in serum samples and grouped by exploratory factor analysis. Analyses yielded three factors, which appear to include biomarkers reflecting different aspects of tumor progression. Elevated factor scores indicate both high levels and strong clustering among serum signals. Factor 1 included VEGF, MMP-9, and TGF-β; suggesting tumor invasion/immunosuppression. Factor 2 included IL-1β, TNF-α, IL-6R, MCP-1; suggesting inflammation/chemotaxis. Factor 3 included IL-6, IL-12, IFN-γ; suggesting inflammation/TH1-type immunity. Hierarchical regressions adjusting age, stage and socioeconomic status examined associations of circadian, distress, and endocrine variables with these three factor scores. Patients with poor circadian coordination as measured by rest-activity rhythms had higher Factor 1 scores (R(2)=.160, p=.038). Patients with elevated CAR also had higher Factor 1 scores (R(2)=.293, p=.020). These relationships appeared to be driven largely by VEGF concentrations. Distress was not related to tumor-relevant biomarkers, and no other significant relationships emerged. Women with strong circadian activity rhythms showed less evidence of tumor promotion and/or progression as indicated by peripheral blood biomarkers. The study was not equipped to discern the cause of these associations. Circadian/endocrine aberrations may be a manifestation of systemic effects of aggressive tumors. Alternatively, these results raise the possibility that, among patients with active breast tumors, disruption of circadian activity rhythms and elevated CAR may facilitate tumor promotion and progression.

Inflammation is reported in post-traumatic stress disorder (PTSD). Few studies have investigated circulating blood cells that may contribute to inflammation. We assessed circulating platelets, white blood cells (WBC) and red blood cells (RBC) in PTSD and assessed their relationship to inflammation and symptom severity. One-hundred and sixty-three male combat-exposed veterans (82 PTSD, 81 non-PTSD) had blood assessed for platelets, WBC, and RBC. Data were correlated with symptom severity and inflammation. All cell counts were significantly elevated in PTSD. There were small mediation effects of BMI and smoking on these relationships. After adjusting for these, the differences in WBC and RBC remained significant, while platelet count was at trend level. In all subjects, all of the cell counts correlated significantly with inflammation. Platelet count correlated with inflammation only in the PTSD subjects. Platelet count, but none of the other cell counts, was directly correlated with PTSD severity ratings in the PTSD group. Combat PTSD is associated with elevations in RBC, WBC, and platelets. Dysregulation of all three major lineages of hematopoietic cells in PTSD, as well as their significant correlation with inflammation, suggest clinical significance of these changes.

Chronic inflammation may be involved in combat-related post-traumatic stress disorder (PTSD) and may help explain comorbid physical diseases. However, the extent to which combat exposure per se, depression, or early life trauma, all of which are associated with combat PTSD, may confound the relationship between PTSD and inflammation is unclear.We quantified interleukin (IL)-6, IL-1β, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and C-reactive protein (CRP) in 51 combat-exposed males with PTSD and 51 combat-exposed males without PTSD, and assessed PTSD and depression severity as well as history of early life trauma. To decrease the possibility of Type I errors, we summed standardized scores of IL-1β, IL-6, TNFα, IFNγ and CRP into a total "pro-inflammatory score". PTSD symptom severity was assessed with the Clinician Administered PTSD Scale (CAPS) rating scale.Subjects with PTSD had significantly higher pro-inflammatory scores compared to combat-exposed subjects without PTSD (p=0.006), and even after controlling for early life trauma, depression diagnosis and severity, body mass index, ethnicity, education, asthma/allergies, time since combat and the use of possibly confounding medications (p=0.002). Within the PTSD group, the pro-inflammatory score was not significantly correlated with depressive symptom severity, CAPS total score, or with the number of early life traumas.Combat-related PTSD in males is associated with higher levels of pro-inflammatory cytokines, even after accounting for depression and early life trauma. These results, from one of the largest studies of inflammatory cytokines in PTSD to date, suggest that immune activation may be a core element of PTSD pathophysiology more so than a signature of combat exposure alone.

Sleep disturbance is a key behavioral risk factor for chronic medical conditions observed at high rates among overweight and obese individuals. Systemic inflammation, including that induced by stress, may serve as a common biological mechanism linking sleep, adiposity, and disease risk. To investigate these relationships, 48 postmenopausal women (mean age=61.8) completed a standardized laboratory stress task during which time blood was collected at baseline and 30+, 50+ and 90+ minutes after stressor onset to assess circulating levels of interleukin (IL)-6, IL-10, and IL-6/IL-10 ratio. Self-reported global sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI) while adiposity was estimated by body mass index. Sagittal diameter was obtained in clinic to estimate visceral abdominal adiposity. Multi-level growth curve models revealed that poorer self-reported sleep quality was associated with greater stress-induced increases in IL-6/IL-10 ratio. In terms of adiposity, higher sagittal diameter, but not BMI, was associated with greater IL-6 reactivity (p’s

BackgroundSocial connections moderate the effects of high negative affect on health. Affective states (anger, fear, and anxiety) predict interleukin-6 (IL-6) reactivity to acute stress; in turn, this reactivity predicts risk of cardiovascular disease progression.PurposeHere, we examined whether perceived social support mitigates the relationship between negative affect and IL-6 stress reactivity.MethodForty-eight postmenopausal women completed a standardized mental lab stressor with four blood draws at baseline and 30, 50, and 90 min after the onset of the stressor and anger, anxiety, and fear were assessed 10 min after task completion. Participants self-rated levels of social support within a week prior to the stressor.ResultsOnly anger was related to IL-6 stress reactivity-those experiencing high anger after the stressor had significant increases in IL-6. IL-6 reactivity was marginally associated with perceived support, but more strikingly, perceived support mitigated anger associations with IL-6 stress reactivity.ConclusionSupportive ties can dampen the relationship of anger to pro-inflammatory reactivity to acute stress. Implications to cardiovascular disease are discussed.

Chronic psychological stress appears to accelerate biological aging, and oxidative damage is an important potential mediator of this process. However, the mechanisms by which psychological stress promotes oxidative damage are poorly understood. This study investigates the theory that cortisol increases in response to an acutely stressful event have the potential to either enhance or undermine psychobiological resilience to oxidative damage, depending on the body's prior exposure to chronic psychological stress. In order to achieve a range of chronic stress exposure, forty-eight post-menopausal women were recruited in a case-control design that matched women caring for spouses with dementia (a chronic stress model) with similarly aged control women whose spouses were healthy. Participants completed a questionnaire assessing perceived stress over the previous month and provided fasting blood. Three markers of oxidative damage were assessed: 8-iso-prostaglandin F(2α) (IsoP), lipid peroxidation, 8-hydroxyguanosine (8-oxoG) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), reflecting oxidative damage to RNA/DNA respectively. Within approximately one week, participants completed a standardized acute laboratory stress task while salivary cortisol responses were measured. The increase from 0 to 30 min was defined as "peak" cortisol reactivity, while the increase from 0 to 15 min was defined as "anticipatory" cortisol reactivity, representing a cortisol response that began while preparing for the stress task. Women under chronic stress had higher 8-oxoG, oxidative damage to RNA (p

Chronic inflammation and oxidative stress have been implicated in the pathophysiology of Major Depressive Disorder (MDD), as well as in a number of chronic medical conditions. The aim of this study was to examine the relationship between peripheral inflammatory and oxidative stress markers in un-medicated subjects with MDD compared to non-depressed healthy controls and compared to subjects with MDD after antidepressant treatment. We examined the relationships between IL-6, IL-10, and the IL-6/IL-10 inflammatory ratio vs. F2-isoprostanes (F2-IsoP), a marker of oxidative stress, in un-medicated MDD patients (n = 20) before and after 8 weeks of open-label sertraline treatment (n = 17), compared to healthy non-depressed controls (n = 20). Among the un-medicated MDD subjects, F2-IsoP concentrations were positively correlated with IL-6 concentrations (p < 0.05) and were negatively correlated with IL-10 concentrations (p < 0.01). Accordingly, F2-IsoP concentrations were positively correlated with the ratio of IL-6/IL-10 (p < 0.01). In contrast, in the control group, there were no significant correlations between F2-IsoPs and either cytokine or their ratio. After MDD subjects were treated with sertraline for 8 weeks, F2-IsoPs were no longer significantly correlated with IL-6, IL-10 or the IL-6/IL-10 ratio. These data suggest oxidative stress and inflammatory processes are positively associated in untreated MDD. Our findings are consistent with the hypothesis that the homeostatic buffering mechanisms regulating oxidation and inflammation in healthy individuals become dysregulated in untreated MDD, and may be improved with antidepressant treatment. These findings may help explain the increased risk of comorbid medical illnesses in MDD.

Background Poorly coordinated diurnal cortisol and circadian rest-activity rhythms predict earlier mortality in metastatic breast and colorectal cancer, respectively. We examined the prognostic value of the diurnal cortisol rhythm in lung cancer. Methods Lung cancer patients (n = 62, 34 female) were within 5 years of diagnosis and had primarily non small-cell lung cancer, with disease stage ranging from early to advanced. Saliva collected over two days allowed calculation of the diurnal cortisol slope and the cortisol awakening response (CAR). Lymphocyte numbers and subsets were measured by flow cytometry. Survival data were obtained for 57 patients. Cox Proportional Hazards analyses were used to test the prognostic value of the diurnal cortisol rhythm on survival calculated both from study entry and from initial diagnosis. Results The diurnal cortisol slope predicted subsequent survival over three years. Early mortality occurred among patients with higher slopes, or relatively “flat” rhythms indicating lack of normal diurnal variation (Cox Proportional Hazards p = .009). Cortisol slope also predicted survival time from initial diagnosis (p = .012). Flattened profiles were linked with male gender (t = 2.04, df = 59, p = .046) and low total and cytotoxic T cell lymphocyte counts (r = −.39 and −.30, p = .004 and .035, respectively). After adjustment for possible confounding factors, diurnal slope remained a significant, independent predictor of survival. Conclusions Flattening of the diurnal cortisol rhythm predicts early lung cancer death. Data contribute to growing evidence that circadian disruption accelerates tumor progression.

Posttraumatic stress disorder (PTSD) is associated with increased risk for Type 2 diabetes and cardiovascular disease (cardiometabolic disease), warranting research into targeted prevention strategies. In the present case–control study of 160 young (mean age 32.7 years) male military veterans, we aimed to assess whether PTSD status predicted increased markers of cardiometabolic risk in otherwise healthy individuals, and further, to explore biological pathways between PTSD and these increased markers of cardiometabolic risk. Toward these aims, we compared measures of cardiometabolic risk, namely insulin resistance (IR) (HOMA-IR), metabolic syndrome (MetS) and prediabetes, between 80 PTSD cases and 80 controls without PTSD. We then determined whether PTSD-associated increases in HOMA-IR were correlated with select biological variables from pathways previously hypothesized to link PTSD with cardiometabolic risk, including systemic inflammation (increased C-reactive protein, interleukin-6, and tumor necrosis factor α), sympathetic over-activity (increased resting heart rate), and neuroendocrine dysregulation (increased plasma cortisol or serum brain-derived neurotrophic factor (BDNF)). We found PTSD diagnosis was associated with substantially higher HOMA-IR (cases 4.3 ± 4.3 vs controls 2.4 ± 2.0; p 0.05). Cases also had increased pro-inflammatory cytokines (p

Poor breast cancer–related quality of life is associated with flattened cortisol rhythms and inflammation in breast cancer survivors and women with advanced disease. We explored the associations of cancer-specific distress (Impact of Events Scale), mood (Profile of Mood States), activity/sleep (wake after sleep onset, 24-hour autocorrelation coefficient) and cortisol (diurnal slope) circadian rhythms, and inflammation (interleukin-6) with quality of life (Functional Assessment of Cancer Therapy–Breast) among patients awaiting breast cancer surgery ( N = 57). Models were adjusted for differences in age and cancer stage. Distress and mood disturbance were significantly correlated with lower quality of life. Ethnic differences in the relationship between distress and mood disturbance with global quality of life and subscales of quality of life were observed. Actigraphic measures showed that in comparison with non-Hispanic patients, African Americans had significantly poorer activity/sleep (wake after sleep onset, 24-hour autocorrelation coefficient). Circadian disruption and inflammation were not associated with quality of life. Physiological dysregulation and associated comorbidities may take time to develop over the course of disease and treatment.

While a relationship between disruption of circadian rhythms and the progression of cancer has been hypothesized in field and epidemiologic studies, it has never been unequivocally demonstrated. We determined the circadian rhythm of cortisol and sleep in women with advanced breast cancer (ABC) under the conditions necessary to allow for the precise measurement of these variables. Women with ABC (n = 97) and age-matched controls (n = 24) took part in a 24-h intensive physiological monitoring study involving polysomnographic sleep measures and high-density plasma sampling. Sleep was scored using both standard clinical metrics and power spectral analysis. Three-harmonic regression analysis and functional data analysis were used to assess the 24-h and sleep-associated patterns of plasma cortisol, respectively. The circadian pattern of plasma cortisol as described by its timing, timing relative to sleep, or amplitude was indistinguishable between women with ABC and age-matched controls (p's > 0.11, t-tests). There was, however, an aberrant spike of cortisol during the sleep of a subset of women, during which there was an eightfold increase in the amount of objectively measured wake time (p

Summary Background The surveillance and effector functions of the immune system are critically dependent on the appropriate distribution of immune cells in the body. An acute or short-term stress response induces a rapid and significant redistribution of immune cells among different body compartments. Stress-induced leukocyte redistribution may be a fundamental survival response that directs leukocyte subpopulations to specific target organs during stress, and significantly enhances the speed, efficacy and regulation of an immune response. Immune responses are generally enhanced in compartments (e.g., skin) that are enriched with leukocytes, and suppressed in compartments that are depleted of leukocytes during/following stress. The experiments described here were designed to elucidate the: (1) Time-course, trajectory, and subpopulation-specificity of stress-induced mobilization and trafficking of blood leukocytes. (2) Individual and combined actions of the principal stress hormones, norepinephrine (NE), epinephrine (EPI), and corticosterone (CORT), in mediating mobilization or trafficking of specific leukocyte subpopulations. (3) Effects of stress/stress hormones on adhesion molecule, L -selectin (CD62L), expression by each subpopulation to assess its adhesion/functional/maturation status. Methods Male Sprague Dawley rats were stressed (short-term restraint, 2–120 min), or adrenalectomized and injected with vehicle (VEH), NE, EPI, CORT, or their combinations, and blood was collected for measurement of hormones and flow cytometric quantification of leukocyte subpopulations. Results Acute stress induced an early increase/mobilization of neutrophils, lymphocytes, helper T cells (Th), cytolytic T cells (CTL), and B cells into the blood, followed by a decrease/trafficking of all cell types out of the blood, except neutrophil numbers that continued to increase. CD62L expression was increased on neutrophils, decreased on Th, CTL, and natural killer (NK) cells, and showed a biphasic decrease on monocytes & B cells, suggesting that CD62L is involved in mediating the redistribution effects of stress. Additionally, we observed significant differences in the direction, magnitude, and subpopulation specificity of the effects of each hormone: NE increased leukocyte numbers, most notably CD62L−/+ neutrophils and CD62L− B cells. EPI increased monocyte and neutrophil numbers, most notably CD62L−/+ neutrophils and CD62L− monocytes, but decreased lymphocyte numbers with CD62L−/+ CTL and CD62L+ B cells being especially sensitive. CORT decreased monocyte, lymphocyte, Th, CTL, and B cell numbers with CD62L− and CD62L+ cells being equally affected. Thus, naive (CD62L+) vs. memory (CD62L−) T cells, classical (CD62L+) vs. non-classical (CD62L−) monocytes, and similarly distinct functional subsets of other leukocyte populations are differentially mobilized into the blood and trafficked to tissues by stress hormones. Conclusion Stress hormones orchestrate a large-scale redistribution of immune cells in the body. NE and EPI mobilize immune cells into the bloodstream, and EPI and CORT induce traffic out of the blood possibly to tissue surveillance pathways, lymphoid tissues, and sites of ongoing or de novo immune activation. Immune cell subpopulations appear to show differential sensitivities and redistribution responses to each hormone depending on the type of leukocyte (neutrophil, monocyte or lymphocyte) and its maturation/functional characteristics (e.g., non-classical/resident or classical/inflammatory monocyte, naive or central/effector memory T cell). Thus, stress hormones could be administered simultaneously or sequentially to induce specific leukocyte subpopulations to be mobilized into the blood, or to traffic from blood to tissues. Stress- or stress hormone-mediated changes in immune cell distribution could be clinically harnessed to: (1) Direct leukocytes to sites of vaccination, wound healing, infection, or cancer and thereby enhance protective immunity. (2) Reduce leukocyte traffic to sites of inflammatory/autoimmune reactions. (3) Sequester immune cells in relatively protected compartments to minimize exposure to cytotoxic treatments like radiation or localized chemotherapy. (4) Measure biological resistance/sensitivity to stress hormones in vivo. In keeping with the guidelines for Richter Award manuscripts, in addition to original data we also present a model and synthesis of findings in the context of the literature on the effects of short-term stress on immune cell distribution and function.

Long-term exposure to stress and its physiological mediators, in particular cortisol, may lead to impaired telomere maintenance. In this study, we examine if greater cortisol responses to an acute stressor and/or dysregulated patterns of daily cortisol secretion are associated with shorter telomere length. Twenty-three postmenopausal women comprising caregivers for dementia partners (n=14) and age- and BMI-matched non-caregivers provided home sampling of cortisol-saliva samples at waking, 30 min after waking, and bedtime, and a 12-hour overnight urine collection. They were also exposed to an acute laboratory stressor throughout which they provided saliva samples. Peripheral blood mononuclear cells were isolated from a fasting blood sample and assayed for telomere length. As hypothesized, greater cortisol responses to the acute stressor were associated with shorter telomeres, as were higher overnight urinary free cortisol levels and flatter daytime cortisol slopes. While robust physiological responses to acute stress serve important functions, the long-term consequences of frequent high stress reactivity may include accelerated telomere shortening.

Psychological distress and coping related to a breast cancer diagnosis can profoundly affect psychological adjustment, possibly resulting in the disruption of circadian rest/activity and cortisol rhythms, which are prognostic for early mortality in metastatic colorectal and breast cancers, respectively. This study aims to explore the relationships of cancer-specific distress and avoidant coping with rest/activity and cortisol rhythm disruption in the period between diagnosis and breast cancer surgery. Fifty-seven presurgical breast cancer patients provided daily self-reports of cancer-specific distress and avoidant coping as well as actigraphic and salivary cortisol data. Distress and avoidant coping were related to rest/activity rhythm disruption (daytime sedentariness, inconsistent rhythms). Patients with disrupted rest/activity cycles had flattened diurnal cortisol rhythms. Maladaptive psychological responses to breast cancer diagnosis were associated with disruption of circadian rest/activity rhythms. Given that circadian cycles regulate tumor growth, we need greater understanding of possible psychosocial effects in cancer-related circadian disruption.

Cognitive and affective responses to acute stress influence pro-inflammatory cytokine reactivity, and peripheral cytokines (particularly interleukin-1 beta (IL-1b)), can act on the brain to promote depressive symptoms. It is unknown whether acute stress-induced changes in positive affect and cognitions (POS) and pro-inflammatory reactivity predict future depressive symptoms. We examined acute stress responses among women, to determine prospective predictors of depressive symptoms. Hypotheses: (1) Stressinduced decreases in POS will be associated with stress-related increases in circulating IL-1b. (2) Acute stress-induced decreases in POS and increases in IL-1b reactivity will predict increases in depressive symptoms 1 year later. Thirty-five post-menopausal women were exposed to acute stress with the Trier Social Stress Task (TSST) and provided blood samples under resting conditions and 30 min after the conclusion of the TSST, which were assayed for IL-1b. IL-1b reactivity was quantified as post minus pre-TSST. Failure to maintain POS was quantified as the decrease in POS during the TSST. Change in depressive symptoms from the study baseline to the following year was determined. Greater acute stress-induced declines in POS were significantly associated with increased IL-1b reactivity (p 6 .02), which significantly predicted increases in depressive symptoms over the following year (p < .01), controlling for age, body mass index, chronic stress, antidepressant use and baseline depressive symptoms. IL-1b reactivity was a significant mediator of the relationship between POS decline and future increases in depressive symptoms (p = .04). Difficulty maintaining positivity under stress and heightened pro-inflammatory reactivity may be markers and/or mechanisms of risk for future increases in depressive symptoms.

Telomerase activity plays an essential role in cel0l survival, by lengthening telomeres and promoting cell growth and longevity. It is now possible to quantify the low levels of telomerase activity in human leukocytes. Low basal telomerase activity has been related to chronic stress in people and to chronic glucocorticoid exposure in vitro. Here we test whether leukocyte telomerase activity changes under acute psychological stress. We exposed 44 elderly women, including 22 high stress dementia caregivers and 22 matched low stress controls, to a brief laboratory psychological stressor, while examining changes in telomerase activity of peripheral blood mononuclear cells (PBMC). At baseline, caregivers had lower telomerase activity levels than controls, but during stress telomerase activity increased similarly in both groups. Across the entire sample, subsequent telomerase activity increased by 18% one hour after the end of the stressor (p

The study of functionally relevant biological effects of serotonin transporter gene promoter region (5-HTTLPR) polymorphisms is especially important given the current controversy about the clinical relevance of these polymorphisms. Here we report an intrinsic immunobiological difference between individuals carrying two short (SS) versus long (LL) 5-HTTLPR alleles, that is observed in healthy subjects reporting low exposure to life stress. Given that 5-HTTLPR polymorphisms are thought to influence susceptibility to depression and are associated with robust neurobiological effects, that depression is associated with higher pro-inflammatory and lower anti-inflammatory cytokines, and that acute stressors increase circulating concentrations of pro-inflammatory cytokines, we hypothesized that compared to LL individuals, SS individuals may show a pro-inflammatory bias under resting conditions and/or during stress. 15 LL and 11 SS individuals participated in the Trier Social Stress Test (TSST). Serum IL-6 and IL-10 were quantified at baseline and 30, 60, 90, and 120 min after beginning the 20-min stress test. Compared to LL individuals, SS individuals showed a higher IL-6/IL-10 ratio at baseline and during stress. Importantly, this pro-inflammatory bias was observed despite both groups being healthy, reporting similar intensities of stress and negative emotionality during the TSST, and reporting similar low exposures to early and recent life stress. To our knowledge, this is the first report of a pro-inflammatory bias/phenotype in individuals carrying the SS genotype of 5-HTTLPR. Thus, healthy SS individuals may be chronically exposed to a pro-inflammatory physiological burden under resting and stress conditions, which could increase their vulnerability to disorders like depression and other diseases that can be facilitated/exacerbated by a chronic pro-inflammatory state.

Cancer treatment is known to have significant immuno-suppressive/dysregulatory effects. Psychological distress and depression, which often accompany cancer diagnosis and treatment, can also suppress or dysregulate endocrine and immune function. Cell-mediated immunity (CMI) is critical for protection against a host of pathogens to which cancer patients may be particularly susceptible. CMI is also important for defense against some tumors. This study explored relationships among depressive symptoms, cortisol secretion, and CMI responses in 72 women with metastatic breast cancer. Depressive symptoms were assessed with the Center for Epidemiologic Studies-Depression Scale (CES-D). Saliva was sampled throughout the day over a 3-day period to obtain a physiologic index of diurnal cortisol concentrations and rhythmicity, which is associated with breast cancer survival time. CMI for specific antigens was measured following intradermal administration of seven commonly encountered antigens (tuberculin, tetanus, diphtheria, Streptococcus, Candida, Trichophyton, and Proteus). Analyses adjusting for relevant medical and treatment variables indicated that women reporting more depressive symptoms showed suppressed immunity as measured by lower average induration size. Women with higher mean diurnal cortisol concentrations also showed suppressed immunity as indicated by a decreased number of antigens to which positive reactions were measured. This study highlights the relationships among depression, stress, and immune function in the context of advanced breast cancer.

Stress is known to suppress or dysregulate immune function and increase susceptibility to disease. Paradoxically, the short-term fight-or-flight stress response is one of nature's fundamental defense mechanisms that galvanizes the neuroendocrine, cardiovascular, and musculoskeletal systems into action to enable survival. Therefore, it is unlikely that short-term stress would suppress immune function at a time when it may be critically required for survival (e.g., in response to wounding and infection by a predator or aggressor). In fact, studies have shown that stress can enhance immune function under certain conditions. Several factors influence the direction (enhancing versus suppressive) of the effects of stress on immune function: (1) DURATION: acute or short-term stress experienced at the time of activation of an immune response enhances innate and adaptive immune responses. Chronic or long-term stress can suppress or dysregulate immune function. (2) Leukocyte distribution: compartments (e.g., skin), that are enriched with immune cells during acute stress show immuno-enhancement, while those that are depleted of leukocytes (e.g., blood), show immuno-suppression. (3) The differential effects of physiologic versus pharmacologic stress hormones: Endogenous hormones in physiological concentrations can have immuno-enhancing effects. Endogenous hormones at pharmacologic concentrations, and synthetic hormones, are immuno-suppressive. (4) Timing: immuno-enhancement is observed when acute stress is experienced during the early stages of an immune response while immuno-suppression may be observed at late stages. The type of immune response (protective, regulatory/inhibitory, or pathological) that is affected determines whether the effects of stress are ultimately beneficial or harmful for the organism. Arguments based on conservation of energy have been invoked to explain potential adaptive benefits of stress-induced immuno-suppression, but generally do not hold true because most mechanisms for immuno-suppression expend, rather than conserve, energy. We propose that it is important to study, and if possible, to clinically harness, the immuno-enhancing effects of the acute stress response that evolution has finely sculpted as a survival mechanism, just as we study its maladaptive ramifications (chronic stress) that evolution has yet to resolve.

Stress is known to suppress immune function and increase susceptibility to infections and cancer. Paradoxically, stress is also known to exacerbate asthma, and allergic, autoimmune and inflammatory diseases, although such diseases should be ameliorated by immunosuppression. Moreover, the short-term fight-or-flight stress response is one of nature’s fundamental defense mechanisms that enables the cardiovascular and musculoskeletal systems to promote survival, and it is unlikely that this response would suppress immune function at a time when it is most required for survival (e.g. in response to wounding and infection by a predator or aggressor). These observations suggest that stress may suppress immune function under some conditions while enhancing it under others. The effects of stress are likely to be beneficial or harmful depending on the type (immunoprotective, immunoregulatory/inhibitory, or immunopathological) of immune response that is affected. Studies have shown that several critical factors influence the direction (enhancing vs. suppressive) of the effects of stress or stress hormones on immune function: (1) Duration (acute vs. chronic) of stress: Acute or short-term stress experienced at the time of immune activation can enhance innate and adaptive immune responses. Chronic or long-term stress can suppress immunity by decreasing immune cell numbers and function and/or increasing active immunosuppressive mechanisms (e.g. regulatory T cells). Chronic stress can also dysregulate immune function by promoting proinflammatory and type-2 cytokine-driven responses. (2) Effects of stress on leukocyte distribution: Compartments that are enriched with immune cells during acute stress show immunoenhancement, while those that are depleted of leukocytes, show immunosuppression. (3) The differential effects of physiologic versus pharmacologic concentrations of glucocorticoids, and the differential effects of endogenous versus synthetic glucocorticoids: Endogenous hormones in physiological concentrations can have immunoenhancing effects. Endogenous hormones at pharmacologic concentrations, and synthetic hormones, are immunosuppressive. (4) The timing of stressor or stress hormone exposure relative to the time of activation and time course of the immune response: Immunoenhancement is observed when acute stress is experienced at early stages of immune activation, while immunosuppression may be observed at late stages of the immune response. We propose that it is important to study and, if possible, to clinically harness the immunoenhancing effects of the acute stress response, that evolution has finely sculpted as a survival mechanism, just as we study its maladaptive ramifications (chronic stress) that evolution has yet to resolve. In view of the ubiquitous nature of stress and its significant effects on immunoprotection as well as immunopathology, it is important to further elucidate the mechanisms mediating stress-immune interactions and to meaningfully translate findings from bench to bedside.

Siberian hamsters ( Phodopus sungorus) exhibit changes in reproductive and immune function in response to seasonal variations in day length. Exposure to short days induces gonadal regression and inhibits testosterone secretion. In parallel, short days enhance immune function: increasing leukocyte numbers and attenuating cytokine and behavioral responses to infection. We examined whether photoperiodic changes in leukocyte phenotypes and sickness behaviors are dependent on concurrent photoperiodic changes in gonadal function. Male hamsters were gonadectomized or sham-gonadectomized and either exposed to short days (9 h light/day; SD) or kept in their natal long-day (15 h light/day; LD) photoperiod for 10–13 wk. Blood samples were obtained for leukocyte enumeration, and hamsters were challenged with bacterial LPS, which induced behavioral (anorexia, reductions in nest building) and somatic (weight loss) sickness responses. Among gonad-intact hamsters, exposure to SD increased total and CD62L+ lymphocytes and CD3+ T lymphocytes in blood and significantly attenuated LPS-induced sickness responses. Independent of photoperiod, castration alone increased total and CD62L+ lymphocyte and CD3+ T lymphocyte numbers and attenuated somatic and anorexic sickness responses. Among castrated hamsters, SD exposure increased lymphocyte numbers and suppressed sickness behaviors. In castrated hamsters, the magnitude of most immunological effects of SD were diminished relative to those evident in gonad-intact hamsters. The SD phenotype in several measures of immunity can be instated via elimination of gonadal hormones alone; however, photoperiodic effects on immune function persist even in castrated hamsters. Thus, photoperiod affects the immune system and neural-immune interactions underlying sickness behaviors via gonadal hormone-dependent and -independent mechanisms.

The biochemical effects of acute and chronic psychological stress have been investigated in male Sprague-Dawley rats using a combination of 1H NMR spectral analysis of plasma and conventional hematological analyses. Animals were subjected to 35 consecutive days of 6-h sessions of stress, and following a 9 day break, were stressed for a further 6-h period. Plasma samples were collected at 0, 1, 3, and 6 h on days 1, 9, 21, 35, and 44, measured using 600 MHz 1H NMR spectroscopy, and analyzed by Principal Components Analysis. Time-dependent biochemical effects of psychological stress on a range of endogenous metabolites were evident and were correlated with the intensity of the stress response as defined by corticosterone and hematological parameters. Following acute stress, increases in the levels of glucose and ketone bodies, and decreases in the levels of acetate, alanine, isoleucine, lactate, leucine, valine, and lipoproteins, were observed. Chronic stress-induced increases in plasma levels of alanine, lactate (day 9), and leucine, valine, and choline (day 44) and decreases in acetate (day 9) and lipoprotein concentrations were observed. Positive correlations between plasma corticosterone level and glucose and glycerol, and between plasma lipoprotein concentrations and hemoglobin levels, were established using Projection to Latent Structures (PLS) analysis. This study indicates the potential of using NMR-based metabonomic strategies for the characterization of endogenous metabolic perturbations induced by psychological stressors and lifestyle choices.

Disturbed regulation of both the hypothalamic-pituitary-adrenal (HPA) axis and sympathoadrenomedullary system in posttraumatic stress disorder (PTSD) suggests that immune function, which is modulated by these systems, may also be dysregulated. Two dermatologic, in vivo measures of immune function, delayed-type hypersensitivity (DTH) and skin barrier function recovery, were examined in female subjects with PTSD and compared to measures in healthy female comparison subjects. In addition, at the time of DTH test placement, circulating numbers of lymphocyte subtypes were assessed. In separate studies, the effects of acute psychological stress on DTH and skin barrier function recovery were examined in healthy volunteer subjects. Both DTH and barrier function recovery were enhanced in women with PTSD. These findings contrast with the effects of acute stress in healthy control subjects, which was associated with suppression of DTH responses and skin barrier function recovery. There was no difference between subjects with PTSD and healthy control subjects in proportions of circulating lymphocyte subsets or in expression of the lymphocyte markers CD62, CD25, and CD45RO/CD45RA. These results suggest that cell-mediated immune function is enhanced in individuals with PTSD, a condition that imposes chronic physiologic and mental stress on sufferers. These findings contrast with suppression of DTH and skin barrier function recovery in healthy volunteers in response to acute psychological stress.

Stress does not cause cancer per se, but depression and a lack of social support might influence cancer progression and clinical outcome. Can identification of the molecular and biological mechanisms involved be used to improve patient treatment? Epidemiological studies indicate that stress, chronic depression and lack of social support might serve as risk factors for cancer development and progression. Recent cellular and molecular studies have identified biological processes that could potentially mediate such effects. This review integrates clinical, cellular and molecular studies to provide a mechanistic understanding of the interface between biological and behavioural influences in cancer, and identifies novel behavioural or pharmacological interventions that might help improve cancer outcomes.