The role of preterm birth in stress-induced sodium excretion in young adults

BACKGROUND

Early-life programming due to prematurity and very low birth weight (VLBW, <1500 g) is believed to contribute to development of hypertension, but the mechanisms remain unclear. Experimental data suggest that altered pressure natriuresis (increased renal perfusion pressure promoting sodium excretion) may be a contributing mechanism. We hypothesize that young adults born preterm will have a blunted pressure natriuresis response to mental stress compared with those born term.

METHODS

In this prospective cohort study of 190 individuals aged 18-23 years, 156 born preterm with VLBW and 34 controls born term with birth weight at least 2500 g, we measured urine sodium/creatinine before and after a mental stress test and continuous blood pressure before and during the stress test. Participants were stratified into groups by the trajectory at which mean arterial pressure (MAP) increased following the test. The group with the lowest MAP trajectory was the reference group. We used generalized linear models to assess poststress urine sodium/creatinine relative to the change in MAP trajectory and assessed the difference between groups by preterm birth status.

RESULTS

Participants' mean age was 19.8 years and 57% were women. Change in urine sodium/creatinine per unit increase in MAP when comparing middle trajectory group against the reference group was greater in those born preterm [β 5.4%, 95% confidence interval (95% CI) -11.4 to 5.3] than those born term (β 38.5%, 95% CI -0.04 to 92.0), interaction term P = 0.002.

CONCLUSION

We observed that, as blood pressure increased following mental stress, young adults born preterm exhibited decreased sodium excretion relative to term-born individuals.

Psychosocial stress and neuroendocrine biomarker concentrations among women living with or without HIV

OBJECTIVE

Women living with HIV (WLWH) experience psychosocial stress related to social-structural vulnerabilities. To investigate neuroendocrine pathways linking stress and increased cardiovascular disease risk among WLWH, we evaluated associations between psychosocial stress (i.e., perceived stress, posttraumatic stress, and experiences of race- and gender-based harassment) and a composite neuroendocrine biomarker index among WLWH and women without HIV.

METHODS

In 2019-2020, Women's Interagency HIV Study participants in Washington, DC completed a questionnaire and provided blood and 12-hour overnight urine samples for testing of serum dehydroepiandrosterone sulfate (DHEA-S) and urinary free cortisol, epinephrine, and norepinephrine. Psychosocial stress was measured using the Perceived Stress Scale, PTSD Checklist-Civilian Version, and Racialized Sexual Harassment Scale. Latent profile analysis was used to classify participants into low (38%), moderate (44%), and high (18%) stress groups. Composite biomarker index scores between 0-4 were assigned based on participants' number of neuroendocrine biomarkers in high-risk quartiles (≥75th percentile for cortisol, epinephrine, and norepinephrine and ≤25th percentile for DHEA-S). We evaluated associations between latent profile and composite biomarker index values using multivariable linear regression, adjusting for socio-demographic, behavioral, metabolic, and HIV-related factors.

RESULTS

Among 90 women, 62% were WLWH, 53% were non-Hispanic Black, and median age was 55 years. In full multivariable models, there was no statistically significant association between psychosocial stress and composite biomarker index values among all women independent of HIV status. High (vs. low) psychosocial stress was positively associated with higher mean composite biomarker index values among all monoracial Black women (adjusted β = 1.32; 95% CI: 0.20-2.43), Black WLWH (adjusted β = 1.93; 95% CI: 0.02-3.83) and Black HIV-negative women (adjusted β = 2.54; 95% CI: 0.41-4.67).

CONCLUSIONS

Despite a null association in the overall sample, greater psychosocial stress was positively associated with higher neuroendocrine biomarker concentrations among Black women, highlighting a plausible mechanism by which psychosocial stress could contribute to cardiovascular disease risk.

Is PTSD-Phenotype Associated with HPA-Axis Sensitivity?: The Endocannabinoid System in Modulating Stress Response in Rats

Endocannabinoids play a role in adaptation to stress and regulate the release of glucocorticoids in stressed and unstressed conditions. We recently found that basal corticosterone pulsatility may significantly impact the vulnerability for developing post-traumatic-stress-disorder (PTSD), suggesting that the endocannabinoid system may contribute to its development. To examine this, we exposed rats to predator scent stress (PSS). Behavioral reactions were recorded seven days post-PSS. Cerebrospinal fluid (CSF) was collected from anesthetized rats shortly after PSS exposure to determine the levels of 2-arachidonoyl glycerol (2-AG) and anandamide (AEA). To correlate between endocannabinoids and corticosterone levels, rats were placed in metabolic cages for urine collection. To assess the levels of endocannabinoids in specific brain regions, rats' brains were harvested one day after behavioral analysis for staining and fluorescence quantification. Moreover, 2-AG was elevated in the CSF of PTSD-phenotype rats as compared with other groups and was inversely correlated with corticosterone urinary secretion. Eight days post-PSS exposure, hippocampal and hypothalamic 2-AG levels and hippocampal AEA levels were significantly more reduced in the PTSD-phenotype group compared to other groups. We posit that maladaptation to stress, which is propagated by an abnormal activation of endocannabinoids, mediates the subsequent stress-induced behavioral disruption, which, later, reduces neuronal the expression of endocannabinoids, contributing to PTSD symptomology.

Time-lag of urinary and salivary cortisol response after a psychological stressor in bonobos (Pan paniscus)

Cortisol is often measured as a marker for stress. Therefore, a profound validation of the time-lag between the stressor and the increase and peak in cortisol levels is needed. No study measured both the urinary and salivary cortisol time-lag after a psychological stressor. In this study, we used a frequent sampling study design to (1) describe the urinary and salivary cortisol pattern during a control day; and (2) characterize the induced excretion pattern of urinary and salivary cortisol after a psychological stressor in six zoo-housed bonobos. Liquid chromatography-tandem mass spectrometry was used to analyze 71 urine and 162 saliva samples collected on a control and a test day. We found that the time-lag between the stressor and the maximal cortisol concentration was similar in urine and saliva (160 min after the stressor). However, salivary cortisol after the stressor did show a faster and steeper increase than urinary cortisol. We also show inter-individual variation in the baseline and stress levels of cortisol, which should be considered in future cortisol studies. Our research highlights the importance of validation studies to confirm relevant sampling windows for cortisol sampling in order to obtain biologically meaningful results.

Urine metabolomic responses to aerobic and resistance training in rats under chronic unpredictable mild stress

Background

It is known that bioenergetics of aerobic and resistance exercise are not the same but both can effectively improve depression. However, it is not clear whether and how different types of exercise can influence depression through the same metabolic regulatory system. Metabolomics provides a way to study the correlation between metabolites and changes in exercise and/or diseases through the quantitative analysis of all metabolites in the organism. The objective of this study was to investigate the effects of aerobic and resistance training on urinary metabolites by metabolomics analysis in a rodent model of depression.

Methods

Male Sprague-Dawley rats were given chronic unpredictable mild stress (CUMS) for eight weeks. The validity of the modeling was assessed by behavioral indices. After four weeks of CUMS, the rats that developed depression were randomly divided into a depression control group, an aerobic training group and a resistance training group. There was also a normal control group. From week 5, the rats in the exercise groups were trained for 30 min per day, five days per week, for four weeks. The urine samples were collected pre and post the training program, and analyzed by proton nuclear magnetic resonance (¹H-NMR) spectroscopy.

Results

Both types of training improved depression-like behavior in CUMS rats. Compared with normal control, 21 potential biomarkers were identified in the urine of CUMS rats, mainly involved in energy, amino acids and intestinal microbial metabolic pathways. Common responses to the training were found in the two exercise groups that the levels of glutamine, acetone and creatine were significantly recalled (all P<0.05) Aerobic training also resulted in changes in pyruvate and trigonelline, while resistance training modified α-Oxoglutarate, citric acid, and trimethylamine oxide (all P<0.05).

Conclusions

Aerobic and resistance training resulted in common effects on the metabolic pathways of alanine-aspartate-glutamate, TCA cycle, and butyric acid. Aerobic training also had effects on glycolysis or gluconeogenesis and pyruvate metabolism, while resistance training had additional effect on intestinal microbial metabolism.

Blood pressure and heart rate during stress in children born small for gestational age

BACKGROUND

Increased sympathetic nervous system activity has been proposed as a potential mechanism for the blood pressure (BP) elevation seen in individuals born small for gestational age (SGA). This study was carried out to detect the changes in BP and heart rate (HR) in children born SGA during exposure to stress and to assess for changes in urinary catecholamine excretion.

METHODS

Nineteen children aged 6-14 years born SGA and 17 age- and gender-matched healthy controls were included in the study. The stress test included a mathematical test and venipuncture. BP and HR were monitored during the test. Spot urine samples were collected at baseline and after the stress test to determine dopamine, epinephrine and norepinephrine levels.

RESULTS

At baseline, there was no difference in BP and HR between the SGA and control groups, but mean urinary norepinephrine levels were slightly higher in the SGA group (55.7 ± 16.1 vs. 43.4 ± 3.8 mcg/gCr; P = 0.10). Compared to the control group, mean maximal HR increase was higher in the SGA group (31.3 ± 3.1 vs. 19.2 ± 3.8%; P = 0.008), and mean duration of maximal HR to baseline HR was longer (186 ± 23 vs. 97 ± 13 s, respectively; P = 0.003). There was a significant negative correlation between birth weight and maximal HR increase (r = -0.497, P = 0.003).

CONCLUSION

Children born SGA showed significantly greater increases in HR and significantly longer periods of tachycardia during exposure to stress than did healthy controls. The rise in HR was inversely correlated with birth weight. These findings suggest that children born SGA have a greater increase in sympathetic response when exposed to stress than do healthy individuals.

Additive contributions of childhood adversity and recent stressors to inflammation at midlife: Findings from the MIDUS study

We examined the joint contributions of self-reported adverse childhood experiences (ACEs) and recent life events (RLEs) to inflammation at midlife, by testing 3 competing theoretical models: stress generation, stress accumulation, and early life stress sensitization. We aimed to identify potential mediators between adversity and inflammation. Participants were 1,180 middle-aged and older adults from the Midlife in the United States (MIDUS) Biomarker Project (M age = 57.3 years, SD = 11.5; 56% female). A composite measure of inflammation was derived from 5 biomarkers: serum levels of C-reactive protein, interleukin-6, fibrinogen, E-selectin, and ICAM-1. Participants provided self-report data regarding ACEs, RLEs, current lifestyle indices (cigarette smoking, alcohol consumption, physical exercise, waist circumference), current depressive symptoms, and demographic/biomedical characteristics. We also used indices of hypothalamic-pituitary-adrenocortical outflow (12-hr urinary cortisol) and sympathetic nervous system output (12-hr urinary norepinephrine and epinephrine). Analyses indicated that ACEs and RLEs were independently associated with higher levels of inflammation, controlling for each other's effects. Their interaction was not significant. The results were consistent with the hypothesis that associations between ACEs and inflammation were mediated through higher urinary norepinephrine output, greater waist circumference, smoking, and lower levels of exercise, whereas higher waist circumference and more smoking partially mediated the association between RLEs and inflammation. In support of the stress accumulation model, ACEs and RLEs had unique and additive contributions to inflammation at midlife, with no evidence of synergistic effects. Results also suggested that norepinephrine output and lifestyle indices may help explain how prior stressors foster inflammation at midlife.

Urinary parabens and polyaromatic hydrocarbons independent of health conditions are associated with adult emotional support needs: USA NHANES, 2005-2008

Everyone needs emotional support at some point in life, but the needs might not always be met. The present study was aimed to investigate the prevalence of unmet needs of emotional support in adults and to identify social, environmental and health attributes in a national and population-based setting in recent years. Data was retrieved from the US National Health and Nutrition Examination Surveys, 2005-2008, including demographics, blood pressure readings, self-reported emotional support needs in the last 12 months, self-reported ever health conditions and urinary environmental chemical concentrations. Statistical analyses included chi-square test, t test, survey-weighted logistic regression modeling and population attributable risk (PAR) estimation. Of 6733 American adults aged 40-80, 1273 (21.0 %) needed more emotional support in the past year. They tended to be aged 40-60, female, Mexican American, other Hispanic, education less than high school, or poverty income ratio 5+. People with higher levels of butyl paraben, ethyl paraben, methyl paraben, 1-hydroxynaphthalene, 2-hydroxynaphthalene, or 9-hydroxyfluorene (but not heavy metals, arsenic, phenols, phthalates, pesticides, or phytoestrogens) or historical diabetes, asthma, arthritis, stroke, thyroid disorder, chronic bronchitis, sleep complaint/disorder, or trouble seeing needed more emotional support. Significant risk associations from environmental chemicals mentioned above have remained after adjusting for historical health conditions as potential mediators. This is the first time examining prevalence of the unmet emotional support in adults and identifying the social, environmental and health attributes. Removal of parabens and polyaromatic hydrocarbons and increasing healthcare for people with health conditions to accommodate emotional support should be considered.

Psychosocial and Neurohormonal Predictors of HIV Disease Progression (CD4 Cells and Viral Load): A 4 Year Prospective Study

Most studies of psychosocial predictors of disease progression in HIV have not considered norepinephrine (NE), a neurohormone related to emotion and stress, even though NE has been related to accelerated viral replication in vitro and impaired response to antiretroviral therapy (ART). We therefore examined NE, cortisol, depression, hopelessness, coping, and life event stress as predictors of HIV progression in a diverse sample. Participants (n = 177) completed psychological assessment, blood draws [CD4, viral load (VL)], and a 15 h urine sample (NE, cortisol) every 6 months over 4 years. Hierarchical linear modeling (HLM) was used to model slope in CD4 and VL controlling for ART at every time point, gender, age, race, SES, and initial disease status. NE (as well as depression, hopelessness, and avoidant coping) significantly predicted a greater rate of decrease in CD4 and increase in VL. Cortisol was not significantly related to CD4, but predicted VL increase. To our knowledge, this is the first study relating NE, in vivo, to accelerated disease progression over an extended time. It also extends our previous 2 year study by relating depressed mood and coping to accelerated disease progression over 4 years.

LC-MS/MS based studies on the anti-depressant effect of hypericin in the chronic unpredictable mild stress rat model

ETHNOPHARMACOLOGICAL RELEVANCE

St John׳s Wort (Hypericum perforatum, SJW) is a widely used herbal medicine in western countries but also an important Uygur drug in China. Hypericin (HY) is the main components in SJW extracts, which is used to treat fatigue, weakness, and mild depression. The aim of this study was to investigate the anti-depression effects of HY on chronic unpredictable mild stress (CUMS) model rats and identify the possible mechanisms.

MATERIALS AND METHODS

In this study, the protective effects of HY on CUMS-induced depression in rats were investigated by using a combination of behavioral assessments and urinary metabolites analysis. Urinary metabolites analyses were performed using LC-MS/MS in conjunction with principal components analysis (PCA) after oral administration of either HY or Venlafaxine (VF) for 27 days. During the procedure of experiment, food consumption, body weight, adrenal gland, thymus and spleen indices, behavior scores, sucrose consumption, and stress hormone levels were measured.

RESULTS

Changes in the classic behavioral tests and pharmacological biochemical indices reflected that HY alleviated the symptoms of depression in a shorter period than VF, which was used as positive control for antidepression. Metabolites analysis of urine revealed that HY affected excitatory amino acids and monoamine neurotransmitter metabolites. Remarkably, urinary valine was increased remarkably by HY, even much higher than CUMS group. These results provide important mechanistic insights into the protective effects of HY against CUMS-induced depression and metabolic dysfunction.

CONCLUSION

As the most important active ingredient in SJW extracts, HY possesses the better protective effect against CUMS-induced depression symptoms and metabolic disturbances.

A single pathophysiological pathway in Takotsubo cardiomyopathy: Catecholaminergic stress

BACKGROUND

Takotsubo cardiomyopathy (TTC) continues to be under-diagnosed, due to its varying presentation, with potentially serious consequences if treatment is delayed.

AIMS

To demonstrate the consistent involvement of catecholaminergic stress in TTC, regardless of the trigger.

METHODS

Between 01 July 2009 and 31 August 2013, patients managed in our centre for thoracic pain syndrome, with or without troponin release, were followed up prospectively. TTC was diagnosed from the apical ballooning seen on left ventricular imaging (angiography or transthoracic echocardiography) in the absence of a significant coronary artery lesion. Triggers (emotional trauma, surgical stress and β2-mimetic intoxication) were recorded; catecholamine-secreting tumours were screened for with a urinary methoxylate-derivative assay.

RESULTS

TTC was diagnosed in 40 out of 2754 (1.5%) patients with thoracic pain syndrome, with or without troponin release. Triggers were emotional trauma (n=29, 72.5%), surgical stress (n=5, 12.5%), adrenergic intoxication (n=3, 7.5%) and catecholaminergic tumour (n=3, 7.5%). Mean left ventricular ejection fraction at admission was 38.0 ± 15.7%. Eight (20%) patients initially showed cardiogenic shock. In-hospital mortality was 7.5%, with no deaths from cardiogenic causes. Thirty-five (94.6%) of the survivors had recovered a normal left ventricular ejection fraction (> 55%) by discharge.

CONCLUSION

Whatever the trigger, the common denominator in TTC is catecholaminergic stress. Classically suggested after emotional trauma, TTC may also be induced by surgical stress or endogenous or iatrogenic β2-mimetic intoxication. The various contexts all have a similarly excellent cardiovascular prognosis if treated early.

Behavioral responses to social separation stressor change across development and are dynamically related to HPA activity in marmosets

Psychosocial stressors activate two distinct stress-response systems, a central, behavioral response, and a peripheral, endocrine response. Both behavioral and endocrine responses to stressors are subject to individual and developmental variables, but it is not known whether stressor induced behaviors are stable across development, and how they correspond with changes in the endocrine component of the stress response. We characterized the development and stability of behavioral responses to a mild psychosocial stressor in marmosets (Callithrix geoffroyi), and assessed the degree to which the behavioral and endocrine stress-response systems were co-activated. The behavioral response to stressors was stable within individuals, but only some stressor-induced behaviors changed as the monkeys developed. Overall, there was more variability in the development of behavioral responses compared to stress-induced endocrine profiles found previously [French et al., 2012. Horm Behav 61:196-203]. In young marmosets, only increased alarm calling was correlated with increased cortisol reactivity, and in older marmosets increased cage manipulations and motor activity were associated with poorer post-stressor cortisol regulation. Because these relationships were so few, we conclude that while the behavioral and endocrine systems follow a similar developmental trajectory, each system maintains a level of independence. Furthermore, the relationship between stressor-induced behaviors and HPA activity changes across development.

Circulating and urinary adrenal corticosterone, progesterone, and estradiol in response to acute stress in female mice (Mus musculus)

In studies of stress, it can be difficult to obtain blood rapidly enough to avoid confounding steroid measures. Noninvasive urinary steroid measures may provide an alternative insofar as they reflect systemic steroids. In Experiment 1, we profiled urinary corticosterone, progesterone, and estradiol in ovariectomized female mice following 1 h on an elevated platform. This increased urinary corticosterone for 3 h and progesterone for 4 h. In Experiment 2, blood and urine samples were obtained at 0-6 h following stressor offset. Females showed increased serum corticosterone and progesterone immediately after stressor offset. Urinary corticosterone was increased at both 0 and 2 h post-stress, while an increase in progesterone 2-6 h after stressor offset was not significant. Estradiol was not influenced by this mild stressor. In Experiment 3, mice were exposed to a more severe 1 h stressor, a rat across a wire-mesh grid. In serum, both corticosterone and progesterone were elevated immediately after stressor offset and returned to baseline within 2 h. In urine, this severe stressor elevated corticosterone immediately and 2 h after stressor offset, and in progesterone 2 h after stressor offset. Estradiol in serum was not dynamic, but it was significantly elevated in urine 4 h after stressor offset. Urinary measures generally reflected systemic measures; however, with a different time course resulting in a longer return to baseline. We suggest that the relative value of serum or urinary steroid measures in mice depends upon the experimental design, and that estradiol may only respond when the stressor is severe.

[The relationship of occupational stress and the level of some hormone metabolites in urine]

OBJECTIVE

To explore the possibility for 17-OHCS, 17-KS, VMA and HVA in urine as indicators of occupational stress identification and evaluation.

METHODS

225 policies were investigated by using convenience sampling and cluster sampling methods, occupational stressors, strains, buffer factors and individual factors were measured by questionnaires. The urine 17-OHCS, 17-KS, VMA and HVA level was tested by ELISA and high performance liquid chromatography method respectively.

RESULTS

The urine 17-OHCS level of the groups with high coworker support and job control scores was lower than that of the groups with low score group (P < 0.05), the urine 17-OHCS level of the group with high negative affectivity score was higher than that of the group with low score group (P < 0.05). The urine 17-KS level of the group with high job security score was lower than that of the counterparts (P < 0.05). The urine VMA level of the group with high coworker support score was lower than that of the counterparts (P < 0.05). The urine HVA level of the group with high coping strategy score was lower than that of counterpart (P < 0.05). Logistic regression analysis revealed that the job control and respect were the protective factors of urine 17-OHCS level increase (OR = 0.353 and 0.352 respectively), but over-commitment, self-esteem and daily hassles were the risk factors of urine 17-OHCS with level increase (OR = 3.391, 2.439, and 2.584 respectively). The risk of urine 17-KS level increase for the groups high job control and job security scores were respectively 0.387, 0.356 times than that of the counterparts, the risk of urine VMA level increase for the group with high negative affectivity score was 2.643 times than that of the counterparts.

CONCLUSION

The urine 17-OHCS, 17-KS and VMA level were potential indicators for occupational stress evaluation.

Urinary interleukin-8 is a biomarker of stress in emergency physicians, especially with advancing age--the JOBSTRESS* randomized trial

Background

Emergency physicians are exposed to greater stress during a 24-hour shift (24 hS) than a 14-hour night shift (14 hS), with an impact lasting several days. Interleukin-8 (IL-8) is postulated to be a chronic stress biomarker. However, no studies have tracked IL-8 over several shifts or used it for monitoring short-term residual stress. The IL-8 response to the shifts may also increase with age. Conveniently, IL-8 can be measured non-intrusively from urine.

Methods

We conducted a shifts-randomized trial comparing 17 emergency physicians’ urinary IL-8 levels during a 24 hS, a 14 hS, and a control day (clerical work on return from leave). Mean levels of IL-8 were compared using a Wilcoxon matched-pairs test. Independent associations of key factors including shifts, stress, and age with IL-8 levels were further assessed in a multivariable generalized estimating equations model.

Results

Mean urinary IL-8 levels almost doubled during and after a 24 hS compared with a 14 hS or a control day. Furthermore, IL-8 levels failed to return to control values at the end of the third day after the shift despite a rest day following the 24 hS. In the multivariable model, engaging in a 24 hS, self-reported stress, and age were independently associated with higher IL-8 levels. A 24 hS significantly increased IL-8 levels by 1.9 ng (p = .007). Similarly, for every unit increase in self-reported stress, there was a 0.11 ng increase in IL-8 levels (p = .003); and for every one year advance in age of physicians, IL-8 levels also increased by 0.11 ng (p = .018).

Conclusion

The 24 hS generated a prolonged response of the immune system. Urinary IL-8 was a strong biomarker of stress under intensive and prolonged demands, both acutely and over time. Because elevated IL-8 levels are associated with cardiovascular disease and negative psychological consequences, we suggest that emergency physicians limit their exposure to 24 hS, especially with advancing age.

Urine scent marking (USM): a novel test for depressive-like behavior and a predictor of stress resiliency in mice

Decreased interest in pleasurable stimuli including social withdrawal and reduced libido are some of the key symptomatic criteria for major depression, and thus assays that measure social and sexual behavior in rodents may be highly appropriate for modeling depressive states. Here we present a novel approach for validating rodent models of depression by assessing male urine scent marking (USM) made in consequence to a spot of urine from a proestrous female. USM is an ethologically important form of sexual communication expressed by males to attract females. The expression of this behavior is highly sensitive and adaptive to environmental cues and social status. We hypothesized that male USM behavior offers a naturalistic measure of social motivation that can be used to evaluate hedonic behaviors relevant to the study of mood disorders. We demonstrated that 1) adult male mice displayed a strong preference for marking proestrous female urine with a high degree of specificity, 2) exposure to chronic social defeat profoundly decreased USM whereas exposure to environmental enrichment increased USM, 3) the standard antidepressant fluoxetine reversed declines in USM induced by social defeat, 4) USM behavior closely correlated with other hedonic measures, and 5) USM scores in non-stressed mice predicted behavioral outcomes after defeat exposure such that mice displaying high preference for marking female urine prior to social defeat showed behavioral resiliency after social defeat. The findings indicate that the USM test is a sensitive, validated measure of psychosocial stress effects that has high predictive value for examination of stress resiliency and vulnerability and their neurobiological substrates.

Oxidatively generated DNA/RNA damage in psychological stress states

Both non-pathological psychological stress states and mental disorders are associated with molecular, cellular and epidemiological signs of accelerated aging. Oxidative stress on nucleic acids is a critical component of cellular and organismal aging, and a suggested pathogenic mechanism in several age-related somatic disorders. The overall aim of the PhD project was to investigate the relation between psychopathology, psychological stress, stress hormone secretion and oxidatively generated DNA and RNA damage, as measured by the urinary excretion of markers of whole-body DNA/RNA oxidation (8-oxodG and 8-oxoGuo, respectively). The main hypothesis was that psychological stress states are associated with increased DNA/RNA damage from oxidation. In a study of 40 schizophrenia patients and 40 healthy controls matched for age and gender, we found that 8-oxodG/8-oxoGuo excretion was increased in schizophrenia patients, providing a possible molecular link between schizophrenia and its associated signs of accelerated aging. We found no association between psychopathology, perceived stress or cortisol secretion and 8-oxodG/8-oxoGuo excretion in the patients. In the controls, there were positive correlations between 8-oxodG/8-ocoGuo excretion and 9AM plasma cortisol, but no associations to perceived stress. In an animal study of experimentally induced chronic stress performed in metabolism cages, we found no increase in urinary 8-oxodG/8-oxoGuo or cerebral (hippocampal and frontal cortex) levels of oxidatively generated nucleic acid damage. However, there was a trend towards an increased expression of genes involved in DNA repair, possibly reflecting a compensatory mechanism. In a study of 220 elderly, mostly healthy individuals from the Italian InChianti cohort, we found a significant association between the 24 h urinary cortisol excretion and the excretion of 8-oxodG/8-oxoGuo, determined in the same samples. Collectively, the studies could not confirm an association between psychological stress and oxidative stress on nucleic acids. Systemic oxidatively generated DNA/RNA damage was increased in schizophrenia, and linked to cortisol levels in healthy humans. Finally, the cerebral repair of DNA may be an aspect of the adaptation that, to our knowledge, has not previously been addressed.

Integration of ¹H NMR and UPLC-Q-TOF/MS for a comprehensive urinary metabonomics study on a rat model of depression induced by chronic unpredictable mild stress

Depression is a type of complex psychiatric disorder with long-term, recurrent bouts, and its etiology remains largely unknown. Here, an integrated approach utilizing ¹H NMR and UPLC-Q-TOF/MS together was firstly used for a comprehensive urinary metabonomics study on chronic unpredictable mild stress (CUMS) treated rats. More than twenty-nine metabolic pathways were disturbed after CUMS treatment and thirty-six potential biomarkers were identified by using two complementary analytical technologies. Among the identified biomarkers, nineteen (10, 11,16, 17, 21–25, and 27–36) were firstly reported as potential biomarkers of CUMS-induced depression. Obviously, this paper presented a comprehensive map of the metabolic pathways perturbed by CUMS and expanded on the multitude of potential biomarkers that have been previously reported in the CUMS model. Four metabolic pathways, including valine, leucine and isoleucine biosynthesis; phenylalanine, tyrosine and tryptophan biosynthesis; tryptophan metabolism; synthesis and degradation of ketone bodies had the deepest influence in the pathophysiologic process of depression. Fifteen potential biomarkers (1–2, 4–6, 15, 18, 20–23, 27, 32, 35–36) involved in the above four metabolic pathways might become the screening criteria in clinical diagnosis and predict the development of depression. Moreover, the results of Western blot analysis of aromatic L-amino acid decarboxylase (DDC) and indoleamine 2, 3-dioxygenase (IDO) in the hippocampus of CUMS-treated rats indicated that depletion of 5-HT and tryptophan, production of 5-MT and altered expression of DDC and IDO together played a key role in the initiation and progression of depression. In addition, none of the potential biomarkers were detected by NMR and LC-MS simultaneously which indicated the complementary of the two kinds of detection technologies. Therefore, the integration of ¹H NMR and UPLC-Q-TOF/MS in metabonomics study provided an approach to identify the comprehensive potential depression-related biomarkers and helpful in further understanding the underlying molecular mechanisms of depression through the disturbance of metabolic pathways.

Evening chronotype is associated with changes in eating behavior, more sleep apnea, and increased stress hormones in short sleeping obese individuals

Background

Short sleep duration and decreased sleep quality are emerging risk factors for obesity and its associated morbidities. Chronotype, an attribute that reflects individual preferences in the timing of sleep and other behaviors, is a continuum from morningness to eveningness. The importance of chronotype in relation to obesity is mostly unknown. Evening types tend to have unhealthy eating habits and suffer from psychological problems more frequently than Morning types, thus we hypothesized that eveningness may affect health parameters in a cohort of obese individuals reporting sleeping less than 6.5 hours per night.

Methodology and Principal Findings

Baseline data from obese (BMI: 38.5±6.4 kg/m²) and short sleeping (5.8±0.8 h/night by actigraphy) participants (n = 119) of the Sleep Extension Study were analyzed (www.ClinicalTrials.gov, identifier NCT00261898). Assessments included the Horne and Ostberg Morningness-Eveningness questionnaire, a three-day dietary intake diary, a 14-day sleep diary, 14 days of actigraphy, and measurements of sleep apnea. Twenty-four hour urinary free cortisol, 24 h urinary norepinephrine and epinephrine levels, morning plasma ACTH and serum cortisol, fasting glucose and insulin, and lipid parameters were determined. Eveningness was associated with eating later in the day on both working and non-working days. Progression towards eveningness was associated with an increase in BMI, resting heart rate, food portion size, and a decrease in the number of eating occasions and HDL-cholesterol. Evening types had overtly higher 24 h urinary epinephrine and morning plasma ACTH levels, and higher morning resting heart rate than Morning types. In addition, Evening types more often had sleep apnea, independent of BMI or neck circumference.

Conclusions

Eveningness was associated with eating later and a tendency towards fewer and larger meals and lower HDL-cholesterol levels. In addition, Evening types had more sleep apnea and higher stress hormones. Thus, eveningness in obese, chronically sleep-deprived individuals compounds the cardiovascular risk associated with obesity.

Home ovulation tests and stress in women trying to conceive: a randomized controlled trial

STUDY QUESTION

Does the use of a digital home ovulation test have any effect on the level of stress in women seeking to conceive?

SUMMARY ANSWER

No difference was found in levels of stress between women using digital ovulation tests to time intercourse compared with women who were trying to conceive without any additional aids: in addition, their use did not negatively impact time to conception in users but may provide additional benefits, including an increased understanding of the menstrual cycle, reassurance and confidence in focusing conception attempts to the correct time in the cycle.

WHAT IS KNOWN ALREADY

It has been suggested that timing of intercourse in such a way that it coincides with ovulation by using ovulation tests can lead to emotional distress; however, no study has been conducted to investigate this hypothesis specifically, until now.

STUDY DESIGN, SIZE AND DURATION

The study was performed over two complete menstrual cycles as a prospective, randomized, controlled trial including quantitative and qualitative methods. The intervention (test) group were given digital ovulation tests to time intercourse to the most fertile time of the cycle and the control group were provided with the current National Institute for Health and Clinical Excellence guidelines for increasing the chances of conception (intercourse every 2-3 days) and asked not to use any additional methods to time when ovulation occurs.

PARTICIPANTS/MATERIALS, SETTING AND METHODS

A total of 210 women who were seeking to conceive were recruited from the general UK population. A total of 115 women were randomized to the test group and 95 to the control group through block randomization. The positive and negative affect schedule (PANAS) and the Perceived Stress Scale (PSS) were used to measure subjective stress levels, the Short-Form 12 health survey was used as a measure of general health and well-being and urine samples were measured for biochemical markers of stress including urinary cortisol. Qualitative data were collected in the form of a telephone interview upon study completion.

MAIN RESULTS AND THE ROLE OF CHANCE

There was no evidence for a difference either in total stress as measured using the PSS or in total positive or negative affect using the PANAS questionnaire between the test and control groups at any time point for the duration of the study. During cycle 1, for example, on Day 6, the difference in total stress score (test-control) was -0.62 [95% confidence interval (CI) -2.47 to 1.24] and on the day of the LH surge, it was 0.53 (95% CI -1.38 to 2.44). In addition, no correlation was observed between time trying to conceive and levels of stress, or between age and levels of stress, and no evidence was found to show that stress affected whether or not a pregnancy was achieved. There is also no evidence that the biochemistry measurements are related to whether a pregnancy was achieved or of a difference in biochemistry between the treatment groups. The use of digital ovulation tests did not negatively affect time to conception and with an adequately sized study, could potentially show improvement. To ensure that the results of this study were not affected by chance, we used a number of different methods for measuring stress, each of which had been independently validated.

LIMITATIONS AND REASONS FOR CAUTION

Randomization occurred before the start of the study because of the need to provide the ovulation tests in readiness for Day 6 of the first cycle. As a consequence, a number of women fell pregnant during this period (22 and 13 in the test and control groups, respectively). A further 15 women were either lost to follow-up or withdrew consent prior to study start. Pregnancy rate was higher overall in the test group, so to ensure that there were sufficient data from women who failed to become pregnant in the test group, we implemented an additional biased recruitment. This second cohort may have been different from the first, although no significant differences were observed between the two phases of recruitment for any of the information collected upon admission to the study.

WIDER IMPLICATIONS OF THE FINDINGS

Women who seek medical advice while trying to conceive should not be discouraged by health care professionals from using digital ovulation tests in order to time intercourse. The cohort of women recruited to this study initially had no evidence of infertility and were looking to conceive in a non-medical setting. A separate study to assess the impact of home ovulation tests in a subfertile population would be of interest and complementary to the present study.

STUDY FUNDING/COMPETING INTERESTS

This study was funded by SPD Swiss Precision Diagnostics, GmbH, manufacturer of Clearblue(®) pregnancy and ovulation tests. SPD Development Company Ltd is a wholly owned subsidiary of SPD Swiss Precision Diagnostics GmbH; together referred to as SPD.

TRIAL REGISTRATION NUMBER

NCT01084304 (www.clinicaltrials.gov).

Circadian rhythm and response to an acute stressor of urinary corticosterone, testosterone, and creatinine in adult male mice

In small laboratory species, steroid measures can be obtained more frequently and less invasively from urine than blood. Insofar as urinary levels reflect systemic levels, they could provide advantages particularly for measurement of glucocorticoids, whose blood levels react rapidly to handling and stress. In Experiment 1, urinary samples were collected from male mice every second hour over a 14:10 h light:dark cycle. Samples were analyzed via enzyme immunoassay for corticosterone, testosterone, and creatinine. Corticosterone had peak concentrations 1 h after light offset and a trough 1 h after light onset. Testosterone showed peak concentrations 5-7 h after light onset and lowest concentrations during the dark phase of the cycle. Creatinine showed some variation over the light-dark cycle, but steroid measures showed similar trends with and without adjustment for creatinine. In Experiment 2, mice were stressed via an injection at times close to the determined peak and trough levels of corticosterone. In urinary samples taken 90 min after injection, corticosterone was significantly higher in injected animals at both times relative to levels in control animals, but testosterone was unaffected by injection stress. In Experiment 3, serum and urine samples were collected from mice every sixth hour across the diurnal cycle. Corticosterone peaked in urine and serum immediately after light offset, and urinary measures predicted those in serum. These data indicate that urinary corticosterone reflects systemic levels in mice, document circadian variation in urinary testosterone, and indicate that circadian variation in creatinine is minimal, but potentially relevant in stressed animals.

Studies of the protein and the energy metabolism in man during a wintering in Antarctica

During the 29th Soviet Antarctic Expedition in Novolazarevskaya from March 1984 to March 1985, the protein and energy metabolisms were studied in six expeditioners from the German Democratic Republic. The investigations were carried out at the beginning of the expedition (May), during the polar night (July) and during the polar day (December). The effect of a special stress situation (sledge trek in April 1984) was investigated in one subject. The stable nitrogen isotope (15)N was used to study the protein metabolism. The assessment of the energy metabolism was based on the oxygen consumption, which was determined by means of a spirograph. In addition, the vital capacity, the breath minute volume, the blood pressure, etc. were measured. The following results were obtained: During the polar night, the utilisation of the dietary proteins and the whole body protein synthesis calculated by means of the (15)N excretion of the total nitrogen in urine were greater (73.6±0.9 % and 3.48±0.17 g protein d(-1) kg(-1), n=3) than the respective values during the polar day (69.7±1.2, p<0.05, n=3 and 3.05±0.07, p<0.05, n=3) and at the beginning of the expedition (69.6±1.4, p<0.02, n=5 and 2.81±0.09, p<0.01, n=5). The lowest values (58.0 % and 2.43 g protein d(-1) kg(-1)) were obtained in the subject after the trek. The resting metabolic rate (in kJ d(-1) m(-2)) was decreased during the polar night (45.6±5.0, n=4) in comparison with the polar day (61.5±11.3, n=3) and the beginning of the expedition (52.3±9.6, n=4) with p<0.01 in both cases.

Tracer kinetics and metabolic models in medicine

In the present paper, a survey of methods applied to the interpretation and evaluation of tracer kinetic data is given. For their mathematical description, both compartmental and non-compartmental models, such as the modified model of Sprinson and Rittenberg, the San Pietro-Rittenberg model, two models of the albumin metabolism and a 10-pool model of the N and protein metabolism were used. By means of single or multiple pulse, infusion and priming techniques, the N and protein metabolism in various metabolic states (e.g. healthy man, pathological and stress conditions, therapeutic treatments) were studied.

Stress system dynamics during "life as it is lived": an integrative single-case study on a healthy woman

Little is known about the dynamic characteristics of stress system activity during "life as it is lived". Using as representative a study design as possible, this investigation sought to gain insights into this area. A healthy 25-year-old woman collected her entire urine over a period of 63 days in 12-h intervals (126 measurements) to determine cortisol and neopterin (immune activation marker) levels. In addition, she filled out questionnaires on emotional state and daily routine in 12-h intervals, and was interviewed weekly to identify emotionally negative and positive everyday incidents. Adjusted cross-correlational analyses revealed that stressful incidents were associated with cyclic response patterns in both urinary cortisol and urinary neopterin concentrations. Urinary cortisol levels first decreased 12-24 h after stressful incidents occurred (lag 1: -.178; p = 0.048) and then increased a total of 72-84 h later (lag 6: +.224; p = 0.013). Urinary neopterin levels first increased 0-12 h before the occurrence of stressful incidents (-lag 1: +.185; p = 0.040) and then decreased a total of 48-60 h following such stressors (lag 4: -.181; p = 0.044). Decreases in urinary neopterin levels were also found 24-36 and 48-60 h after increases in pensiveness (lag 2: -.215; p = 0.017) and depressiveness (lag 4: -.221; p = 0.014), respectively. Findings on emotionally positive incidents sharply contrasted with those dealing with negative experiences. Positive incidents were followed first by urinary cortisol concentration increases within 12 h (lag 0: +.290; p = 0.001) and then by decreases after a total of 60-72 h (lag 5: -.186; p = 0.039). Urinary neopterin levels first decreased 12-24 h before positive incidents occurred (-lag 2: -.233; p = 0.010) and then increased a total of 12-24 h following these incidents (lag 1: +.222; p = 0.014). As with previous investigations on patients with systemic lupus erythematosus (SLE), this study showed that stress system response can be considerably longer and more complex and differentiated than findings from conventional group studies have suggested. Further integrative single-case studies will need to be conducted in order to draw firm conclusions about stress system dynamics under real-life conditions.

Stress reactivity in young marmosets (Callithrix geoffroyi): ontogeny, stability, and lack of concordance among co-twins

Variation in response styles in the hypothalamic-pituitary-adrenal (HPA) axis are known to be predictors of short- and long-term health outcomes. The nature of HPA responses to stressors changes with developmental stage, and some components of the stress response exhibit long-term individual consistency (i.e., are trait-like) while others are transient or variable (i.e., state-like). Here we evaluated the response of marmoset monkeys (Callithrix geoffroyi) to a standardized social stressor (social separation and exposure to a novel environment) at three different stages of development: juvenile, subadult, and young adult. We monitored levels of urinary cortisol (CORT), and derived multiple measures of HPA activity: Baseline CORT, CORT reactivity, CORT Area Under the Curve (AUC), and CORT regulation. Juvenile marmosets exhibited the most dramatic stress response, had higher AUCs, and tended to show poorer regulation. While baseline CORT and CORT regulation were not consistent within an individual across age, CORT reactivity and measures of AUC were highly correlated across time; i.e., individuals with high stress reactivity and AUC as juveniles also had high measures as subadults and adults, and vice-versa. Marmoset co-twins did not exhibit similar patterns of stress reactivity. These data suggest that regardless of the source of variation in stress response styles in marmosets, individually-distinctive patterns are established by six months of age, and persist for at least a year throughout different phases of marmoset life history.

Social isolation affects partner-directed social behavior and cortisol during pair formation in marmosets, Callithrix geoffroyi

Pair-bonded relationships form during periods of close spatial proximity and high sociosexual contact. Like other monogamous species, marmosets form new social pairs after emigration or ejection from their natal group resulting in periods of social isolation. Thus, pair formation often occurs following a period of social instability and a concomitant elevation in stress physiology. Research is needed to assess the effects that prolonged social isolation has on the behavioral and cortisol response to the formation of a new social pair. We examined the sociosexual behavior and cortisol during the first 90-days of cohabitation in male and female Geoffroy's tufted-ear marmosets (Callithrix geoffroyi) paired either directly from their natal group (Natal-P) or after a prolonged period of social isolation (ISO-P). Social isolation prior to pairing seemed to influence cortisol levels, social contact, and grooming behavior; however, sexual behavior was not affected. Cortisol levels were transiently elevated in all paired marmosets compared to natal-housed marmosets. However, ISO-P marmosets had higher cortisol levels throughout the observed pairing period compared to Natal-P marmoset. This suggests that the social instability of pair formation may lead to a transient increase in hypothalamic-pituitary-adrenal (HPA) axis activity while isolation results in a prolonged HPA axis dysregulation. In addition, female social contact behavior was associated with higher cortisol levels at the onset of pairing; however, this was not observed in males. Thus, isolation-induced social contact with a new social partner may be enhanced by HPA axis activation, or a moderating factor.

Antidepressant-like effects of the fractions of Xiaoyaosan on rat model of chronic unpredictable mild stress

ETHNOPHARMACOLOGICAL RELEVANCE

Xiaoyaosan (XYS), composed of Radix Bupleuri, Radix Angelicae Sinensis, Radix Paeoniae Alba, Rhizoma Atractylodis Macrocephalae, Poria, Herba Menthae, Rhizoma Zingiberis Recens and Radix Glycyrrhizae, is a valuable traditional Chinese medicine (TCM) which is used for the treatment of depression in China. In the formula, Radix Bupleuri usually serves as the principal drug, Radix Angelicae Sinensis and Radix Paeoniae Alba serve as the ministerial drugs, Rhizoma Atractylodis Macrocephalae, Poria, Herba Menthae and Rhizoma Zingiberis Recens serve as adjunctive drugs, Radix Glycyrrhizae serves as messenger drug, they coordinate with each other and enhance the effect of the formula. In our previous experiments, the antidepressant effect of XYS was revealed. However, the antidepressant part (or component) of this prescription was still obscure. We divided the XYS into five different polar fractions, and explored the antidepressant activity of five different polar fractions to identify the active fraction.

MATERIALS AND METHODS

Behavior research and metabonomics method based on (1)H NMR were used for efficacy study of different fractions in chronic unpredictable mild stress (CUMS) model of depression. Rats were divided into 8 groups and drugs were administered during the 21 days model building period. The urine samples of rats were collected overnight (12h) on 21 day and the metabolic profiling of the urine was measured using NMR. Multivariate analysis was also utilized to evaluate the active fraction of XYS.

RESULTS

In the behavior research, there were significant difference between the lipophilic fraction group (XY-A) and the model group. In addition, with pattern recognition analysis of urinary metabolites, the results showed a clear separation of the model group and control group, while XY-A group was much closer to the control group in the OSC-PLS score plot. Seven endogenous metabolites contributing to the separation of the model group and control group were detected, while XY-A group regulated the 5 perturbed metabolites showing a tendency of recovering to control group.

CONCLUSIONS

The present work suggested that petroleum ether fraction was the most effective fraction, implying that lipophilic components contribute to the antidepressant effect of XYS.

The effects of a long-term psychosocial stress on reproductive indicators in the baboon

Psychosocial stress is thought to negatively impact fecundity, but human studies are confounded by variation in nutrition and lifestyle. Baboons offer a useful model to test the effect of prolonged mild stress on reproductive indicators in a controlled setting. Following relocation from social groups to solitary housing, a previously documented stressful event for nonhuman primates, daily urine samples, tumescence, and menstrual bleeding were monitored in twenty baboons (Papio sp.) for 120-150 days. Specimens were assayed for estrone conjugates (E1C), pregnanediol-3-glucuronide (PDG), follicle-stimulating hormone (FSH), and cortisol. Linear mixed effects models examined (1) the effects of stress on frequency of anovulation, hormone levels, tumescence and cycle length, and (2) the relationship of cortisol with reproductive indicators. Despite cortisol levels indicative of stress, anovulation was negligible (1% in 102 cycles). PDG, FSH, cycle length, and tumescence declined during the first four cycles, but began recovery by the fifth. Cortisol was negatively associated with FSH but not associated with PDG, E1C or tumescence. Ovulation, E1C, and luteal phase length were not affected. Tumescence tracked changes in FSH and PDG, and thus may be a useful indicator of stress on the reproductive axis. Elevated cortisol was associated with reduced FSH, supporting a model of cortisol action at the hypothalamus rather than the gonad. After four to five menstrual cycles the reproductive indicators began recovery, suggesting adjustment to new housing conditions. In conclusion, individual housing is stressful for captive baboons, as reflected by cortisol and reproductive indicators, although ovulation, a relatively direct proxy for fecundity, is unaffected.

Adiponectin and negative mood in healthy premenopausal and postmenopausal women

Negative mood and stress are associated with cardiovascular and metabolic disease. There are likely many physiological mechanisms underlying the poor health outcomes. The relationship of psychological states (negative mood, life stress, and stress-responsive hormones) and adiponectin, an adipokine that promotes insulin sensitivity, was investigated in two separate studies. The two groups of participants included 52 healthy, premenopausal women, and 63 postmenopausal women with a range of stress levels. The relationship between adiponectin and psychological state (perceived stress and negative mood) was examined cross-sectionally in both groups of participants, but also prospectively (1 year later) in the group of postmenopausal women. In premenopausal women, negative mood and nocturnal urinary epinephrine were significantly related to adiponectin, independent of BMI. In postmenopausal women, negative mood was not associated with adiponectin cross-sectionally, but negative mood was a significant predictor for lower levels of adiponectin 1 year later, independent of initial adiponectin concentrations and changes in body mass index. Lastly, having a depressive disorder was related to lower adiponectin. As adiponectin levels are associated with insulin resistance, obesity, and diabetes mellitus, these findings suggest there may be an adiponectin-mediated pathway explaining in part how negative mood affects metabolic health. Mechanistic studies are needed to explore this potential relationship further.

Dynamics of social and energetic stress in wild female chimpanzees

Stress hormone measurements can reinforce and refine hypotheses about the costs of particular contexts or behaviors in wild animals. For social species, this is complicated because potential stressors may come from the physical environment, social environment, or some combination of both, while the stress response itself is generalized. Here, we present a multivariate examination of urinary cortisol dynamics over 6 years in the lives of wild female chimpanzees in the Kanyawara community of Kibale National Park, Uganda. We hypothesized that chimpanzee socioecology provides strong indications of both energetic and social stress to females, but that the salience of these stressors might vary over a female's life history in accordance with their changing reproductive costs and social interactions. Using linear mixed models, we found that urinary cortisol levels increased significantly with age but were also elevated in young immigrants to the community. Across reproductive states, cycling, non-estrous females had relatively low cortisol compared to lactating, estrous, or pregnant females. Aggression from males led to higher cortisol levels among estrous females, frequent targets of aggressive sexual coercion. In contrast, energetic stress was most salient to lactating females, who experienced higher cortisol during months of low fruit consumption. Low dominance rank was associated with increased cortisol, particularly during the energetically demanding period of lactation. The effects of female conflict were felt widely, even among those who were the primary aggressors, providing further evidence that long-term resource competition, while apparently muted, exerts a far-reaching impact on the lives of chimpanzee females.

Sleep symptoms during the menopausal transition and early postmenopause: observations from the Seattle Midlife Women's Health Study

STUDY OBJECTIVES

Describe the severity of getting to sleep, nighttime awakening, and early morning awakening across the menopausal transition (MT) and early postmenopause (PM) and their relationship to age, menopausal transition factors, symptoms, stress-related factors, and health related factors.

DESIGN

Cohort.

SETTING

community.

PARTICIPANTS

286 women from the Seattle Midlife Women's Health Study cohort.

MEASUREMENTS

Participants completed annual menstrual calendars for MT staging, diaries in which they rated their symptoms, stress levels, and perceived health multiple times per year from 1990-2007 and provided first morning urine samples assayed for E1G, FSH, cortisol, and catecholamines. Multilevel modeling (R program) was used for data analysis.

RESULTS

Severity of self-reported problems going to sleep was associated with all symptoms, perceived stress, history of sexual abuse, perceived health (-), alcohol use (-) (all P < 0.001), and lower cortisol (P = 0.009), but not E1G or FSH. Severity of nighttime awakening was significantly associated with age, late MT stage, and early PM, FSH, E1G (-), hot flashes, depressed mood, anxiety, joint pain, backache, perceived stress, history of sexual abuse, perceived health (-), and alcohol use (-) (all P < 0.001, except E1G for which P = 0.030). Severity of early morning awakening was significantly associated with age, hot flashes, depressed mood anxiety, joint pain, backache, perceived stress, history of sexual abuse, perceived health (-) (all P < or = 0.001, except E1G for which P = 0.02 and epinephrine (P = 0.038), but not MT stages or FSH. Multivariate models for each symptom included hot flashes, depressed mood, and perceived health.

CONCLUSION

Sleep symptoms during the MT may be amenable to symptom management strategies that take into account the symptom clusters and promote women's general health rather than focusing only on the MT.

Heart rate variability and urinary catecholamines from job stress in korean male manufacturing workers according to work seniority

The aim of this study was to evaluate the relationships between job stress and indicators of autonomic nervous system activity in employees of the manufacturing industry. A total of 140 employees from a company that manufactures consumer goods (i.e., diapers and paper towels) were recruited for participation in this study. Job stress was assessed using Karasek's Job Content Questionnaire. Heart rate variability (HRV) was measured using a heart rate monitor, and urinary catecholamines were measured by an HPLC-ECD. Information on demographic characteristics, previous job history, smoking status and alcohol consumption was also collected. Job stress did not have a significant effect on HRV or catecholamines. However, low-frequency HRV was significantly higher in the high-strain group of subjects with a short duration of employment. Low- and high-frequency HRV were higher in the high-strain group than in the low-strain group, but these differences were not statistically significant. The results of the present study indicate that low-frequency HRV was significantly higher in the high-strain group of subjects with a short duration of employment. In addition, the results of this study show that HRV can be used as a potential physiologic indicator of job stress in employees with a short duration of employment.

Mood and cortisol responses following tryptophan-rich hydrolyzed protein and acute stress in healthy subjects with high and low cognitive reactivity to depression

BACKGROUND & AIMS

It is suggested that stress particularly in subjects with high cognitive reactivity (CR), a psychological vulnerability marker of depression, may increase or even induce serotonergic vulnerability, which in turn may lead to reduced serotonin (5-HT) function, decreased stress coping and an increased risk to develop depressive symptoms. The aim of the present study was to investigate the beneficial effects of 5-HT augmentation through a tryptophan-rich hydrolyzed protein (HP) on mood and stress coping in subjects with high and low CR. We hypothesized that subjects with high CR are more responsive to the beneficial effects of HP than subjects with low CR particularly after acute stress exposure.

METHODS

In a double-blind, crossover study, participants' mood and cortisol was assessed before and after acute stress exposure either following intake of HP or a standard casein protein (CP) as control condition.

RESULTS

HP significantly increased positive mood in all subjects and dampened the cortisol response to acute stress. No differences were found between high and low CR subjects.

CONCLUSIONS

To conclude, because dietary treatment with HP has beneficial effects on mood and physiological stress coping in both high and low CR subjects, HP may be a good dietary method for augmenting brain TRP and 5-HT and thus 5-HT linked stress resilience.

Urinary cortisol responses to unusual events in captive chimpanzees (Pan troglodytes)

This study investigated the urinary cortisol stress response to one known stressor (anaesthesia) and three unusual events hypothesized to result in increases in cortisol (confinement to one half of an enclosure for several days due to a hurricane, an enrichment exercise, and a change in group composition) in young chimpanzees (Pan troglodytes). Although a cortisol stress response to a variety of laboratory experiences has been documented in captive animals, it is unclear whether other types of atypical events are stressful, including those that are not necessarily negative. Cortisol was measured in 519 urine samples collected from 20 awake, unrestrained chimpanzees; individuals were compared against their own baseline values. A significant increase in urinary cortisol concentration was found as a result of the stress of anaesthesia, but no significant change in urinary cortisol resulted from the three other potential stressors. A lack of a urinary cortisol response to these events may indicate that the events were not actually stressful for the chimpanzees, but may have resulted from the limited temporal resolution of measuring cortisol excretion as an indicator of integrated secretion, or from changes in rates of agonistic behaviors.

Stress in cynomolgus monkeys (Macaca fascicularis) subjected to long-distance transport and simulated transport housing conditions

The stress associated with transportation of non-human primates used in scientific research is an important but almost unexplored part of laboratory animal husbandry. The procedures and routines concerning transport are not only important for the animals' physical health but also for their mental health as well. The transport stress in cynomolgus monkeys (Macaca fascicularis) was studied in two experiments. In Experiment 1, 25 adult female cynomolgus monkeys were divided into five groups of five animals each that received different diets during the transport phase of the experiment. All animals were transported in conventional single animal transport cages with no visual or tactile contact with conspecifics. The animals were transported by lorry for 24 h at ambient temperatures ranging between 20 degrees C and 35 degrees C. Urine produced before, during and after transport was collected and analysed for cortisol by enzyme-linked immunosorbent assay (ELISA). All monkeys exhibited a significant increase in cortisol excretion per time unit during the transport and on the first day following transport.Although anecdotal reports concerning diet during transport, including the provision of fruits and/or a tranquiliser, was thought likely to influence stress responses, these were not corrobated by the present study. In Experiment 2, behavioural data were collected from 18 cynomolgus macaques before and after transfer from group cages to either single or pair housing, and also before and after a simulated transport, in which the animals were housed in transport cages. The single housed monkeys were confined to single transport cages and the pair housed monkeys were kept in their pairs in double size cages. Both pair housed and singly housed monkeys showed clear behavioural signs of stress soon after their transfer out of their group cages.However, stress-associated behaviours were more prevalent in singly housed animals than in pair housed animals, and these behaviours persisted for a longer time after the simulated transport housing event than in the pair housed monkeys. Our data confirm that the transport of cynomolgus monkeys is stressful and suggest that it would be beneficial for the cynomolgus monkeys to be housed and transported in compatible pairs from the time they leave their group cages at the source country breeding facility until they arrive at their final laboratory destination in the country of use.

Relation between psychoneuroendocrine profile in stressful conditions and antibodies to herpesvirus 6 and 7

The aim of the present study is to evaluate whether the individual susceptibility to infectious disease is influenced by the psychological profile of cadets exposed to stressful events associated with military lifestyle in academy and if the neuroendocrine responses to stressful events is related with humoral immunity estimated by measuring antibody titres to human herpesvirus (HHV-6)7 (HHV-7) and to what extent it is influenced by personality traits. It has been observed that cadets with lower psychoaptitude scores (1-2) have a significant higher susceptibility to infectious disease (x2=7.95; p=0.019) compared to subjects with higher scores. A positive relationship between cortisol and antibody titers to HHV-6 (r=0.304; p=0.024) it has been found. It can be interesting to observe that antibody titers on HHV-6 are also related to psychoaptitude profile (r=0.239; p=0.044). The antibody titers to HHV-7 are negatively related to the 5 scales of BFQ and in particular with subdimension Co (cordiality) of BFQ (r=0.401; p=0.002). The survey carried out on over 1,500 cadets of the Military Academy of Modena shows that the susceptibility to infectious diseases during the first six months of admission to the Academy seem to be influenced by the psychoaptitudinal profile. The finding of a positive relationship between serum cortisol and antibody vs HHV-6 suggests that the impairment of the immune system linked to circulatory cortisol levels may induce a reactivation of a latent herpesvirus 6 with related increase of antibody titers.

Chronic psychosocial stress affects corticotropin-releasing factor in the paraventricular nucleus and central extended amygdala as well as urocortin 1 in the non-preganglionic Edinger-Westphal nucleus of the tree shrew

Stressful stimuli evoke neuronal and neuroendocrine responses helping an organism to adapt to changed environmental conditions. Chronic stressors may induce maladaptive responses leading to psychiatric diseases, such as anxiety and major depression. A suitable animal model to unravel mechanisms involved in the control of adaptation to chronic stress is the psychological subordination stress in the male tree shrew. Subordinate male tree shrews exhibit chronic hypothalamo-pituitary-adrenal (HPA) activation as reflected in continuously elevated cortisol secretion, and structural changes in the hippocampal formation. Corticotropin-releasing factor (CRF) is the major peptide released upon activation of the HPA axis in response to stress. Recent evidence suggests that besides CRF, urocortin 1 (Ucn1) also plays a role in stress adaptation. We have tested the significance of CRF and Ucn1 in adaptation to chronic psychosocial stress in male tree shrews exposed for 35 days to daily psychosocial conflict, by performing semi-quantitative immunocytochemistry for CRF in the parvocellular hypothalamic paraventricular nucleus (pPVN), extended amygdala, viz. central extended amygdala (CeA) and dorsolateral nucleus of the bed nucleus of the stria terminalis (BNSTdl) as well as that for Ucn1 in the non-preganglionic Edinger-Westphal nucleus (npEW). Compared to unstressed animals, psychosocial stress resulted in an immediate and sustained activation of the HPA axis and sympathetic tone as well as reduced testosterone concentration and decreased body and testis weights vs. non-stressed tree shrews. In the pPVN, the number of CRF-immunoreactive neurons and the specific signal density of CRF-immunoreactive fiber terminals in the CeA were strongly reduced (-300 and -40%, respectively; P<0.05), whereas no significant difference in CRF fiber density was found in BNSTdl. The npEW revealed 4 times less Ucn1-immunoreactive neurons (P<0.05). These clear effects on both Ucn1- and CRF-neuropeptide contents may reflect a crucial mechanism enabling the animal to adapt successfully to the stressors, and point to the significance of the pPVN, CeA and npEW in stress-induced brain diseases.

Urinary free cortisol levels among depressed men and women: differential relationships to age and symptom severity?

BACKGROUND

Preclinical and clinical models of depression suggest sex differences may be mediated at least in part, by differences in hormonal modulation of hypothalamic-pituitary-adrenal (HPA) axis activity. Unraveling the consequences of moderating influences from the effect of sexual dimorphism will be vital to elaborating models of pathophysiology.

METHODS

The current study investigated urinary free cortisol (UFC) among younger adults with mild to moderate major depressive disorder to clarify the relationship with potential demographic and clinical moderators.

RESULTS

Male patients had higher mean UFC levels than female patients. Moreover, significant interactions between age and severity were found among men, but not women. In contrast to prior findings, neither age nor severity effects on UFC levels were found among female patients.

LIMITATIONS

Conclusions from the current study are limited by the absence of cortisol data from matched controls. Thus it was not possible to disentangle sex differences in baseline physiology from that of pathophysiological differences tied specifically to depression.

CONCLUSIONS

Despite several methodological limitations, the interactions between sex and both age and severity in this large sample of depressed patients are suggestive of differential pathophysiology for regulation of UFC excretion, and could reflect a neuroprotective effect for estrogen among younger depressed women.

Increased catecholamines and heart rate in children with low birth weight: perinatal contributions to sympathoadrenal overactivity

BACKGROUND

Low birth weight is associated with cardiovascular disease. The underlying mechanisms are unknown. We hypothesized that perinatal stress alters autonomic regulation of the cardiovascular system. In this study, catecholamines, heart rate (HR) and blood pressure (BP) were measured in healthy children with low birth weight.

METHODS

This clinical study included 105 children (mean age 9.6 years) in three groups; born at term with normal birth weight (controls, n=37), born at term but small for gestational age (SGA, n=29) and born preterm (Preterm, n=39). Dopamine, adrenaline and noradrenaline were determined in urine. HR and BP were measured at rest, during an orthostatic test and after a mathematical mental stress test.

RESULTS

Children in the Preterm and SGA groups excreted higher levels of catecholamines when compared with controls. HR (mean [SD] values) were higher at rest and after mental stress in Preterm (at rest 76 [9] and after mental stress 82 [12] min(-1)) and in SGA (79 [8] and 82 [10]) when compared with controls (70 [9] and 75 [9]). HR correlated with urinary catecholamines (r=0.24-0.27, P<0.05). Blood pressures measured at rest, during orthostatic testing and after mental stress did not differ between the groups.

CONCLUSIONS

Preterm birth and fetal growth restriction are associated with increased sympathoadrenal activity in childhood, as indicated by stress-induced increases in HR and urinary catecholamines. These findings suggest that the cardiovascular control is differently programmed in these children with possibly higher risk of developing hypertension in adulthood.

Urine from stressed rats increases immobility in receptor rats forced to swim: Role of 2-heptanone

The present study was aimed to determine whether the urine from donor rats, which were physically stressed (UD-PS) by unavoidable electric footshocks, produces despair in receptor partner rats (RP) in the long-term. For each trial, an RP rat was placed during 10 min once per day for 21 days in a small non-movement-restricting cage impregnated with the urine collected from a UD-PS rat. Control rats, free of stimulation, maintained their locomotion and immobility scores at basal values throughout the 21-day test. After 21 days of stressing experience [F(2,90)=15.22, P<0.0001] locomotion significantly increased in RP rats (r=0.938, P<0.01), whereas in the UD-PS group locomotion decreased (r=-0.606, P<0.05). The RP and UD-PS groups displayed the longest time of immobility [F(2,90)=8.83, P<0.001] in the forced-swim test (RP, r=0.886, P<0.05; UD-PS, r=0.962, P<0.001) compared with the control group (r=-0.307, NS). We conclude that the RP became similarly despaired as the UD-PS group through the action of 2-heptanone, a ketonic compound identified in UD-PS urine by HS-GC/MS techniques. This ketone was found to be increased [F(2,15)=3.50, P<0.05] from the 1st day of unavoidable electric footshocks, and to induce despair, an effect reverted [F(2,21)=16.5, P<0.0001] by imipramine (5.0 mg/kg) in another group of rats.

Effect of stress on erythrocyte deformability, influence of gender and menstrual cycle

This study aimed to investigate the effect of acute mental stress on erythrocyte deformability (ED) in women during different phases of the menstrual cycle and to compare the results with men. For this purpose, healthy males (n=10) and females (n=10) (during follicular and luteal phases) underwent Stroop color-word interference and cold pressor tests. Hemoglobin, hematocrit and leukocyte counts before and after this stress test revealed no difference in either group; erythrocyte sedimentation rate was significantly lower in the post-test samples in all. In all groups erythrocyte filtration time was significantly higher and thus ED was significantly lower after the stress test (mean+/-SEM, PRE-TEST: follicular: 3.08+/-0.05; luteal: 2.07+/-0.05; men: 2.9+/-0.05) (POST-TEST: follicular: 4.5+/-0.07; luteal: 4.1+/-0.07; men: 4.39+/-0.1). ED was appreciably influenced by gender and menstrual cycle. Women at the luteal phase had better ED compared to both women at the follicular phase and men, the effect being especially pronounced in the pre-test samples. Our results suggest that stress may induce cardiovascular diseases by lowering ED in both genders. The effect of stress on ED varies with gender and during different phases of the menstrual cycle, which may be explained by variations in the sex hormones.

Maternal psychological distress, prenatal cortisol, and fetal weight

OBJECTIVE

The objective of this study was to examine the effects of maternal psychological distress on estimated fetal weight during midgestation and explore the maternal hypothalamic-pituitary axis and sympathoadrenal dysregulation as potential risk factors for these effects.

METHODS

Fetal ultrasound biometry measurements and maternal sociodemographic characteristics, emotional distress symptoms, and first morning urine samples were collected during a clinical ultrasound examination for a cross-sectional sample of 98 women who were between 16 and 29 weeks pregnant. Fetal weight was estimated from ultrasound biometry measurements; maternal emotional distress was assessed using the daily hassles (stress), Center for Epidemiologic Studies-Depression (depression), and State-Trait Anxiety Inventory (anxiety) scales; and urine samples were assayed for cortisol and norepinephrine levels.

RESULTS

Correlation analyses revealed that both maternal psychological (daily hassles, depression, and anxiety) and biochemical (cortisol and norepinephrine) variables were negatively related to fetal biometry measurements and estimated fetal weight. A structural equation model further revealed that when the independent variance of maternal sociodemographic, psychological distress, and biochemistry measures were accounted for, prenatal cortisol was the only significant predictor of fetal weight.

CONCLUSIONS

Women exhibiting psychological distress during pregnancy exhibit elevated cortisol levels during midgestation that are in turn related to lower fetal weight.

Behavioural and physiological responses of dogs entering re-homing kennels

Behaviour and urinary cortisol/creatinine ratios (C/C) were monitored in twenty-six dogs, on days 1, 2, 3, 5, 7 and 10 following their admission to a rehoming kennel. Half had been relinquished from homes, and half were either strays or returns to the shelter. Drinking and grooming increased with time, while panting and paw-lifting decreased, but only drinking was linked with C/C; dogs observed drinking on the first day had significantly lower C/C than dogs not observed drinking. Mean molar C/C (40 x 10(-6)+/-16 x 10(-6)) tended to decrease with time in the strays and returns, and to increase in dogs relinquished from homes, although C/C on the first day was highly variable and not distinguishable between these two groups. This implies that these populations differed in their long-term, but possibly not their short-term, responses to kennelling. Dogs with rising C/C were more active on average than those with falling C/C, but the opposite trend was detected when making comparisons within-dog. The relationship between C/C and exercise is therefore complex and warrants further investigation before C/C can be considered as a reliable indicator of welfare in this species.

Effect of multiple oral doses of androgenic anabolic steroids on endurance performance and serum indices of physical stress in healthy male subjects

Anabolic androgenic steroids (AAS) are doping agents that are mostly used for improvement of strength and muscle hypertrophy. In some sports, athletes reported that the intake of AAS is associated with a better recovery, a higher training load capacity and therefore an increase in physical and mental performances. The purpose of this study was to evaluate, the effect of multiple doses of AAS on different physiological parameters that could indirectly relate the physical state of athletes during a hard endurance training program. In a double blind settings, three groups (n = 9, 8 and 8) were orally administered placebo, testosterone undecanoate or 19-norandrostenedione, 12 times during 1 month. Serum biomarkers (creatine kinase, ASAT and urea), serum hormone profiles (testosterone, cortisol and LH) and urinary catecholamines (noradrenalin, adrenalin and dopamine) were evaluated during the treatment. Running performance was assessed before and after the intervention phase by means of a standardized treadmill test. None of the measured biochemical variables showed significant impact of AAS on physical stress level. Data from exercise testing on submaximal and maximal level did not reveal any performance differences between the three groups or their response to the treatment. In the present study, no effect of multiple oral doses of AAS on endurance performance or bioserum recovery markers was found.

[Stress effects of 72-hour sleep deprivation]

Stress effects of 3-d (72-hr) continuous vigilance were studied for renal excretion of 17-oxycorticoids (17-KS), electrolytes (potassium and sodium), and liquid. The investigation involved 12 male subjects aged 23 to 36. Baseline parameters displayed diurnal variations with comparatively high day and comparatively low night values. During the 72-hr vigilance, significant and consistent (statistically fiducial) intensification of 17-KS and potassium excretion occurred in the night-time, i.e., in the period of naturally low values, but only in the first two sleepless nights. As for sodium and liquid excretion, stress-related reduction in these parameters was more consistent and distinct in the day-time, i.e., in the period of naturally high values, rather than in the nighttime. Therefore, the two factors that should be accounted for by investigators of continuous vigilance (and, maybe, other stresses) are the anticipated direction of a stress-reaction and baseline diurnal variation of parameters under study. If stress is expected to increase a parameter, measurements should be done when the parameter is naturally low and, vice versa, if stress is known to reduce a parameter, then measurement should be planned in the period when it is naturally high. If direction of stress-related changes is predictable, investigations can be performed on a twenty-four hour basis.

Stress barometer at diagnoses in children with school non-attendance

BACKGROUND

School non-attendance is a major social problem in Japan. Many children stop attending school for a variety of reasons. The authors previously reported stress barometer values for healthy Japanese children. In this study, the authors examined the stress barometer values of children with school non-attendance.

METHODS

The authors measured stress barometer values, that is, urinary 17-hydroxycorticosteroids (17-OHCS) and 17-ketosteroid sulfates (17-KS-S) in 65 children (40 girls and 25 boys; 7-15 years of age) with school non-attendance, except for pervasive developmental disorder and mental retardation, who attended the outpatient department of Dokkyo University School of Medicine Hospital, Tochigi, Japan, during the past 4 years.

RESULTS

A total of 24 (36.9%) of the 65 children had urinary 17-OHCS values above 2SD, and 14 (21.5%) had urinary 17-OHCS below 2SD. In total, 10 (15.4%) children had urinary 17-KS-S values above 2SD, and four (6.2%) had urinary 17-KS-S below 2SD. Five (7.7%) children had urinary 17-KS-S/17-OHCS values above 2SD, and 10 (15.4%) had urinary 17-KS-S/17-OHCS below 2SD.

CONCLUSION

The stress barometer values appear to be clinically useful for evaluating objectively whether children with school non-attendance have emotional stress.

The effectiveness of a 15 minute weekly massage in reducing physical and psychological stress in nurses

OBJECTIVE

To investigate the effectiveness of massage therapy in reducing physiological and psychological indicators of stress in nurses employed in an acute care hospital.

DESIGN

Randomised controlled trial.

SETTING

Acute care hospital in Queensland.

SUBJECTS

Sixty nurses were recruited to the five week study and randomly assigned to two groups.

INTERVENTION

A 15 minute back massage once a week. The control group did not receive any therapy.

MAIN OUTCOME MEASURES

Demographic information, a life events questionnaire and a brief medical history of all participants was completed at enrolment. Physiological stress was measured at weeks one, three and five by urinary cortisol and blood pressure readings. Psychological stress levels were measured at weeks one and five with the State-Trait Anxiety Inventory (STAI).

RESULTS

Differences in the change in urinary cortisol and blood pressure between the two groups did not reach statistical significance. However, STAI scores decreased over the five weeks for those participants who received a weekly massage. The STAI scores of the control group increased over the five week period. These differences between the groups were statistically significant.

CONCLUSION

The results of this study suggest that massage therapy is a beneficial tool for the health of nurses as it may reduce psychological stress levels. It is recommended that further large studies be conducted to measure the symptoms of stress rather than the physiological signs of stress in nurses.

Anxiety and stress among science students. Study of calcium and magnesium alterations

Stress and anxiety of university science students (Chemistry) was evaluated in basal conditions and during exams using validated stress and anxiety questionnaires. The relations between the data obtained and various biochemical markers were established. Results showed that the evaluated students did not experience stress increase as a consequence of exams but suffered a significant increase in anxiety. The psychological findings agree with the urinary biomarkers studied. It is known that anxiety is related to partial magnesium reduction associated with a urinary magnesium excretion increase, as observed in the present data. Nevertheless, stress also correlates with a urinary calcium increase which was not detected in the present study.