Psychoneuroendocrinology of depression. Hypothalamic-pituitary-adrenal axis

Child protection and adult depression: evaluating the long-term consequences of evacuating children to foster care during World War II

This paper combined data collected from war time government records with survey data including background characteristics, such as factors that affected eligibility, to examine the adult depression outcomes of individuals who were evacuated from Finland to temporary foster care in Sweden during World War II. Using war time government records and survey data for a random sample of 723 exposed individuals and 1321 matched unexposed individuals, the authors conducted least squares adjusted means comparison to examine the association between evacuation and adult depression (Beck Depression Inventory). The random sample was representative for the whole population of evacuees who returned to their biological families after World War II. The authors found no statistically significant difference in depressive symptoms during late adulthood between the two groups; for example, the exposed group had a 0.41 percentage points lower average Beck Depression Inventory score than the unexposed group (p = 0.907). This study provides no support for family disruption during early childhood because of the onset of sudden shocks elevating depressive symptoms during late adulthood.

MIF: mood improving/inhibiting factor?

Although major depressive disorder imposes a serious public health burden and affects nearly one in six individuals in developed countries over their lifetimes, there is still no consensus on its pathophysiology. Inflammation and cytokines have emerged as a promising new avenue in depression research, and, in particular, macrophage migration inhibitory factor (MIF) has been shown to be significant in depression physiology. In this review we summarize current research on MIF and depression. We highlight the arguments for MIF as a pro- and antidepressant species and discuss the potential implications for therapeutics.

Depression and disease severity in patients with premature acute coronary syndrome

OBJECTIVES

The association between depression and cardiovascular disease severity in younger patients has not been assessed, and sex differences are unknown. We assessed whether major depression and depressive symptoms were associated with worse cardiovascular disease severity in patients with premature acute coronary syndrome, and we assessed sex differences in these relationships.

METHODS

We enrolled 1023 patients (aged ≤ 55 years) hospitalized with acute coronary syndrome from 26 centers in Canada, the United States, and Switzerland, through the GENdEr and Sex determInantS of cardiovascular disease: From bench to beyond-Premature Acute Coronary Syndrome study. Left ventricular ejection fraction, Killip class, cardiac troponin I, and Global Registry of Acute Coronary Events score data were collected through chart review.

RESULTS

The sample comprised 248 patients with major depression and 302 women. In univariate analyses, major depression was associated with a lower likelihood of having an abnormal left ventricular ejection fraction (odds ratio, 0.70; 95% confidence interval, 0.51-0.97; P = .03) and lower troponin I levels (estimate, -4.04; 95% confidence interval, -8.01 to -0.06; P = .05). After adjustment for sociodemographic and clinical characteristics, neither major depression nor depressive symptoms were associated with disease severity indices, and there were no sex differences.

CONCLUSION

The increased risk of adverse events in depressed patients with premature acute coronary syndrome is not explained by disease severity.

High novelty-seeking rats are resilient to negative physiological effects of the early life stress

Exposure to early life stress dramatically impacts adult behavior, physiology, and neuroendocrine function. Using rats bred for novelty-seeking differences and known to display divergent anxiety, depression, and stress vulnerability, we examined the interaction between early life adversity and genetic predisposition for high- versus low-emotional reactivity. Thus, bred Low Novelty Responder (bLR) rats, which naturally exhibit high anxiety- and depression-like behavior, and bred High Novelty Responder (bHR) rats, which show low anxiety/depression together with elevated aggression, impulsivity, and addictive behavior, were subjected to daily 3 h maternal separation (MS) stress postnatal days 1-14. We hypothesized that MS stress would differentially impact adult bHR/bLR behavior, physiology (stress-induced defecation), and neuroendocrine reactivity. While MS stress did not impact bHR and bLR anxiety-like behavior in the open field test and elevated plus maze, it exacerbated bLRs' already high physiological response to stress - stress-induced defecation. In both tests, MS bLR adult offspring showed exaggerated stress-induced defecation compared to bLR controls while bHR offspring were unaffected. MS also selectively impacted bLRs' (but not bHRs') neuroendocrine stress reactivity, producing an exaggerated corticosterone acute stress response in MS bLR versus control bLR rats. These findings highlight how genetic predisposition shapes individuals' response to early life stress. Future work will explore neural mechanisms underlying the distinct behavioral and neuroendocrine consequences of MS in bHR/bLR animals.

Disruption of fetal hormonal programming (prenatal stress) implicates shared risk for sex differences in depression and cardiovascular disease

Comorbidity of major depressive disorder (MDD) and cardiovascular disease (CVD) represents the fourth leading cause of morbidity and mortality worldwide, and women have a two times greater risk than men. Thus understanding the pathophysiology has widespread implications for attenuation and prevention of disease burden. We suggest that sex-dependent MDD-CVD comorbidity may result from alterations in fetal programming consequent to the prenatal maternal environments that produce excess glucocorticoids, which then drive sex-dependent developmental alterations of the fetal hypothalamic-pituitary-adrenal (HPA) axis circuitry impacting mood, stress regulation, autonomic nervous system (ANS), and the vasculature in adulthood. Evidence is consistent with the hypothesis that disruptions of pathways associated with gamma aminobutyric acid (GABA) in neuronal and vascular development and growth factors have critical roles in key developmental periods and adult responses to injury in heart and brain. Understanding the potential fetal origins of these sex differences will contribute to development of novel sex-dependent therapeutics.

Effect of selective serotonin reuptake inhibitors and immunomodulator on cytokines levels: an alternative therapy for patients with major depressive disorder

Major depressive disorder (MDD) is a psychiatric illness that presents as a deficit of serotonergic neurotransmission in the central nervous system. MDD patients also experience alterations in cortisol and cytokines levels. Treatment with selective serotonin reuptake inhibitors (SSRIs) is the first-line antidepressant regimen for MDD. The aim of this study was to determine the effect of a combination of SSRIs and an immunomodulator-human dialyzable leukocyte extract (hDLE)-on cortisol and cytokines levels. Patients received SSRIs or SSRIs plus hDLE. The proinflammatory cytokines IL-1 β , IL-2, and IFN- γ ; anti-inflammatory cytokines IL-13 and IL-10; and 24-h urine cortisol were measured at weeks (W) 0, 5, 20, 36, and 52 of treatment. The reduction in cortisol levels in the SSRI-treated group was 30% until W52, in contrast, the combined treatment induced a 54% decrease at W36. The decline in cortisol in patients who were treated with SSRI plus hDLE correlated with reduction of anti-inflammatory cytokines and increases levels of proinflammatory cytokines at the study conclusion. These results suggest that the immune-stimulating activity of hDLE, in combination with SSRIs, restored the pro- and anti-inflammatory cytokine balance and cortisol levels in depressed patients versus those who were given SSRIs alone.

Psychosocial functioning and vascular endothelial growth factor in patients with head and neck cancer

BACKGROUND

Psychosocial functioning is associated with vascular endothelial growth factor (VEGF) in various patient populations. This study examined whether psychosocial functioning in patients with head and neck squamous cell carcinoma (HNSCC) is associated with tumor VEGF expression, a protein that stimulates angiogenesis and is associated with poor prognosis.

METHODS

Forty-two newly diagnosed patients completed assessments of psychosocial functioning (ie, depressive symptoms, perceived stress, anxiety, social support) before surgery. Tumor samples were obtained for VEGF analysis and human papillomavirus (HPV)-typing.

RESULTS

Poorer psychosocial functioning was associated with greater VEGF expression controlling for disease stage (odds ratio [OR], 4.55; 95% confidence interval [CI], 1.72-12.0; p < .01). When examined by HPV status, the association between psychosocial functioning and VEGF remained significant among patients who were HPV negative (OR, 5.50; 95% CI, 1.68-17.3; p < .01), but not among patients who were HPV positive.

CONCLUSION

These findings inform our understanding of the biobehavioral pathways that may contribute to poor outcomes in non-HPV-associated HNSCCs.

Leptin and its association with somatic depressive symptoms in patients with the metabolic syndrome

BACKGROUND

This study aimed to determine the association between circulating leptin levels and total depressive symptoms as well as depressive symptom dimensions (cognitive and somatic) after controlling for important confounding factors.

METHODS

The study sample was comprised of 135 participants with the metabolic syndrome. Depressive symptoms were measured using the Beck Depression Inventory-II. Leptin was measured using a leptin-specific enzyme immunoassay. Inflammation was assessed using C-reactive protein and interleukin-6 levels.

RESULTS

Leptin was significantly associated with somatic depressive symptoms (β = 0.33, P = 0.018), but not total depressive symptoms (β = 0.27, P = 0.067) or cognitive depressive symptoms (β = 0.21, P = 0.182), after controlling for age, gender, body mass index, and insulin resistance. Further adjustment for C-reactive protein and interleukin-6 levels did not alter the relationship (β = 0.32, P = 0.023) between circulating leptin levels and somatic depressive symptoms.

CONCLUSIONS

Leptin is independently associated with somatic depressive symptoms in patients with the metabolic syndrome.

Early adverse care, stress neurobiology, and prevention science: lessons learned

There is growing evidence that some of the difficulties observed among children who have experienced early adverse care (e.g., children internationally adopted from institutional care and maltreated children in foster care) involve experience-induced alterations in stress-responsive neurobiological systems, including the hypothalamic-pituitary-adrenocortical (HPA) system. Thus, incorporating stress neurobiology into prevention research could aid in identifying the children most in need of preventive intervention services, elucidating the mechanisms of change in effective interventions, and providing insight into the differential responses of children to effective interventions. However, integrating stress neurobiology and prevention research is challenging. In this paper, the results of studies examining HPA system activity in children who have experienced early adverse care are reviewed, the implications of these results for prevention research are discussed, and critical steps for successfully incorporating stress neurobiology into prevention research are identified.

Examining the developmental interface of cortisol and depression symptoms in young adolescent girls

Despite the substantial amount of data supporting a link between HPA-axis functioning and depression, the ontogeny of this association is not known. The aim of the present study was to contribute data on the developmental interface of HPA-axis functioning and depression in girls by testing associations between repeated measures of depression symptoms and cortisol levels in childhood and early adolescence. Girls (N=232) and their mothers, who were participating in a longitudinal study, were interviewed about depression symptoms annually from ages 9 to 12 years. Cortisol was assayed from saliva at ages 10 and 12 years upon arrival to the lab and following administration of the cold pressor task (CPT). Time of day of collection of saliva and level of pubertal development were included as covariates in model testing. Although most girls did not show an increase in cortisol in response to the CPT, lower levels of output during the CPT were associated with higher levels of depression symptoms. These findings were observed only for cortisol levels assessed at age 12 years. Girls with low levels of cortisol output at age 12, and decreases in output from ages 10 to 12, had stable or slightly increasing depression symptoms from ages 9 to 12 years. We conclude that associations between HPA-axis functioning and depression emerge as early as age 12. However, individual differences in cortisol levels at age 12 also were associated with depression symptoms at earlier ages. The data suggest two possibilities: (1) that childhood depression is associated with HPA-axis dysregulation, but that age related changes in the sensitivity or plasticity of the HPA-axis may result in a delay in the emergence of such an association, or (2) that dysregulation of the functioning of the HPA-axis develops following repeated experience of depression symptoms.

Neuroendocrine markers and psychological features in patients with irritable bowel syndrome

BACKGROUND AND AIMS

The key role of the brain-gut axis in the pathophysiology of irritable bowel syndrome (IBS) has been recognized. The aim of this study was to assess the possible association between IBS, neuroendocrine markers, and psychological features.

METHODS

One hundred and twenty-five consecutive IBS patients and 105 healthy subjects were enrolled. Plasma serotonin, plasma and urinary cortisol, and plasma neuropeptide Y levels were evaluated. All patients were given a questionnaire to assess IBS symptom severity. In 66 patients, a psychodiagnostic assessment was carried out.

RESULTS

A high incidence of specific psychological features, including state anxiety (69.69 %), trait anxiety (54.54 %), obsessions and compulsions (28.78 %), was observed in IBS patients. A positive correlation between neuropeptide Y and state anxiety (r = 0.287, p = 0.024) and simulation/social ingenuity (r = 0.269, p = 0.039) was found in these patients. In diarrhea-predominant IBS, plasma cortisol was linearly related to plasma serotonin (r = 0.5663, p < 0.001).

CONCLUSIONS

In IBS patients, a significant correlation was found between specific psychological features and neuroendocrine markers, especially plasma cortisol and neuropeptide Y; in diarrhea-predominant IBS, a correlation between plasma cortisol and serotonin was found, although it needs to be confirmed in more extensive cohorts.

The serotonin transporter gene-linked polymorphic region (5-HTTLPR) and cortisol stress reactivity: a meta-analysis

Recent meta-analyses have stimulated an active debate on whether the serotonin transporter gene-linked polymorphic region (5-HTTLPR) is associated with an elevated vulnerability to psychiatric diseases upon exposure to environmental adversity. As a potential mechanism explaining genotype-dependent differences in stress sensitivity, altered stress-induced activation of the hypothalamus-pituitary-adrenal (HPA) axis has been investigated in several experimental studies, with most of these studies comprising small samples. We evaluated the association of 5-HTTLPR genotype and cortisol reactivity to acute psychosocial stress by applying a meta-analytical technique based on eleven relevant data sets (total N=1686), which were identified through a systematic literature search up to October 2011. This meta-analysis indicates a small (d=0.27), but significant association between 5-HTTLPR genotype and HPA-axis reactivity to acute psychosocial stress with homozygous carriers of the S allele displaying increased cortisol reactivity compared with individuals with the S/L and L/L genotype. The latter association was not further moderated by participants' age, sex or the type of stressor. Formal testing revealed no evidence for a substantial selection or publication bias. Our meta-analytical results are consistent with a wide variety of experimental studies indicating a significant association between 5-HTTLPR genotype and intermediate phenotypes related to stress sensitivity. Future studies are needed to clarify the consistency of this effect and to further explore whether altered HPA-axis stress reactivity reflects a potential biological mechanism conveying an elevated risk for the development of stress-related disorders in S allele carriers.

HPA-axis hormone modulation of stress response circuitry activity in women with remitted major depression

Decades of clinical and basic research indicate significant links between altered hypothalamic-pituitary-adrenal (HPA)-axis hormone dynamics and major depressive disorder (MDD). Recent neuroimaging studies of MDD highlight abnormalities in stress response circuitry regions which play a role in the regulation of the HPA-axes. However, there is a dearth of research examining these systems in parallel, especially as related to potential trait characteristics. The current study addresses this gap by investigating neural responses to a mild visual stress challenge with real-time assessment of adrenal hormones in women with MDD in remission and controls. Fifteen women with recurrent MDD in remission (rMDD) and 15 healthy control women were scanned on a 3T Siemens MR scanner while viewing neutral and negative (stress-evoking) stimuli. Blood samples were obtained before, during, and after scanning for the measurement of HPA-axis hormone levels. Compared to controls, rMDD women demonstrated higher anxiety ratings, increased cortisol levels, and hyperactivation in the amygdala and hippocampus, p<0.05, family-wise error (FWE)-corrected in response to the stress challenge. Among rMDD women, amygdala activation was negatively related to cortisol changes and positively associated with the duration of remission. Findings presented here provide evidence for differential effects of altered HPA-axis hormone dynamics on hyperactivity in stress response circuitry regions elicited by a well-validated stress paradigm in women with recurrent MDD in remission.

Distribution of the glucocorticoid receptor in the human amygdala; changes in mood disorder patients

Exposure to stress activates the hypothalamic-pituitary-adrenal (HPA) axis that stimulates glucocorticoid (GC) release from the adrenal. These hormones exert numerous effects in the body and brain and bind to a.o. glucocorticoid receptors (GR) expressed in the limbic system, including the hippocampus and amygdala. Hyperactivity of the HPA axis and disturbed stress feedback are common features in major depression. GR protein is present in the human hypothalamus and hippocampus, but little is known-neither in healthy subjects nor in depressed patients-about GR expression in the amygdala, a brain structure involved in fear and anxiety. Since chronic stress in rodents affects GR expression in the amygdala, altered GR protein level in depressed versus healthy controls can be expected. To test this, we investigated GR-α protein expression in the post-mortem human amygdala and assessed changes in ten major or bipolar depressed patients and eight non-depressed controls. Abundant GR immunoreactivity was observed in the human amygdala, both in neurons and astrocytes, with a similar pattern in its different anatomical subnuclei. In major depression, GR protein level as well as the percentage of GR-containing astrocytes was significantly higher than in bipolar depressed patients or in control subjects. Taken together, the prominent expression of GR protein in the human amygdala indicates that this region can form an important target for corticosteroids and stress, while the increased GR expression in major, but not bipolar, depression suggests possible involvement in the etiology of major depression.

Cortisol secretion in depressed, and at-risk adults

Distinct patterns of cortisol secretion have been associated with depression in past research, but it remains unclear whether individuals at-risk for depression may also have similar patterns of cortisol secretion. This is the first study to date of both naturalistic diurnal cortisol secretion and cortisol reactivity to a psychosocial laboratory stressor in depressed and at-risk adults. Cortisol secretion patterns were compared for 57 currently depressed, at-risk (based on trait-level positive and negative affect), and control participants over 5 days and in response to a laboratory stressor. After controlling for potentially confounding biobehavioral variables, the depressed group had a larger cortisol awakening response (CAR) and higher average diurnal cortisol compared to control participants. Individuals at-risk for depression also had significantly higher waking cortisol levels than control participants. Results for the psychosocial laboratory stressor did not show the predicted elevations in cortisol for depressed and at-risk participants compared to controls. The at-risk group recovered more quickly when compared to the depressed group both in levels of cortisol and concurrent measures of negative affect. The at-risk and depressed participants were similar on the diurnal cortisol measures, but differed on response to the laboratory social stressor, suggesting divergence in cortisol secretion patterns between currently depressed and temperamentally at-risk individuals. Further investigation of HPA functioning of individuals at-risk for depression may clarify the stress processes involved in risk for depression onset.

Biomarkers in bipolar disorder: a positional paper from the International Society for Bipolar Disorders Biomarkers Task Force

Although the etiology of bipolar disorder remains uncertain, multiple studies examining neuroimaging, peripheral markers and genetics have provided important insights into the pathophysiologic processes underlying bipolar disorder. Neuroimaging studies have consistently demonstrated loss of gray matter, as well as altered activation of subcortical, anterior temporal and ventral prefrontal regions in response to emotional stimuli in bipolar disorder. Genetics studies have identified several potential candidate genes associated with increased risk for developing bipolar disorder that involve circadian rhythm, neuronal development and calcium metabolism. Notably, several groups have found decreased levels of neurotrophic factors and increased pro-inflammatory cytokines and oxidative stress markers. Together these findings provide the background for the identification of potential biomarkers for vulnerability, disease expression and to help understand the course of illness and treatment response. In other areas of medicine, validated biomarkers now inform clinical decision-making. Although the findings reviewed herein hold promise, further research involving large collaborative studies is needed to validate these potential biomarkers prior to employing them for clinical purposes. Therefore, in this positional paper from the ISBD-BIONET (biomarkers network from the International Society for Bipolar Disorders), we will discuss our view of biomarkers for these three areas: neuroimaging, peripheral measurements and genetics; and conclude the paper with our position for the next steps in the search for biomarkers for bipolar disorder.

The current state of play on the molecular genetics of depression

BACKGROUND

It has been well established that both genes and non-shared environment contribute substantially to the underlying aetiology of major depressive disorder (MDD). A comprehensive overview of genetic research in MDD is presented. Method Papers were retrieved from PubMed up to December 2011, using many keywords including: depression, major depressive disorder, genetics, rare variants, gene-environment, whole genome, epigenetics, and specific candidate genes and variants. These were combined in a variety of permutations.

RESULTS

Linkage studies have yielded some promising chromosomal regions in MDD. However, there is a continued lack of consistency in association studies, in both candidate gene and genome-wide association studies (GWAS). Numerous factors may account for variable results including the use of different diagnostic approaches, small samples in early studies, population stratification, epigenetic phenomena, copy number variation (CNV), rare variation, and phenotypic and allelic heterogeneity. The conflicting results are also probably, in part, a consequence of environmental factors not being considered or controlled for.

CONCLUSIONS

Each research group has to identify what issues their sample may best address. We suggest that, where possible, more emphasis should be placed on the environment in molecular behavioural genetics to identify individuals at environmental high risk in addition to genetic high risk. Sequencing should be used to identify rare and alternative variation that may act as a risk factor, and a systems biology approach including gene-gene interactions and pathway analyses would be advantageous. GWAS may require even larger samples with reliably defined (sub)phenotypes.

Effects of cortisol on memory in women with borderline personality disorder: role of co-morbid post-traumatic stress disorder and major depression

BACKGROUND

Stress and cortisol administration are known to have impairing effects on memory retrieval in healthy humans. These effects are reported to be altered in patients with major depressive disorder (MDD) and post-traumatic stress disorder (PTSD) but they have not yet been investigated in borderline personality disorder (BPD).

METHOD

In a placebo-controlled cross-over study, 71 women with BPD and 40 healthy controls received either placebo or 10 mg of hydrocortisone orally before undertaking a declarative memory retrieval task (word list learning) and an autobiographical memory test (AMT). A working memory test was also applied.

RESULTS

Overall, opposing effects of cortisol on memory were observed when comparing patients with controls. In controls, cortisol had impairing effects on memory retrieval whereas in BPD patients cortisol had enhancing effects on memory retrieval of words, autobiographical memory and working memory. These effects were most pronounced for specificity of autobiographical memory retrieval. Patients with BPD alone and those with co-morbid PTSD showed this effect. We also found that co-morbid MDD influenced the cortisol effects: in this subgroup (BPD + MDD) the effects of cortisol on memory were absent.

CONCLUSIONS

The present results demonstrate beneficial effects of acute cortisol elevations on hippocampal-mediated memory processes in BPD. The absence of these effects in patients with co-morbid MDD suggests that these patients differ from other BPD patients in terms of their sensitivity to glucocorticoids (GCs).

Salivary cortisol in women with major depressive disorder under selective serotonin reuptake inhibitors therapy

Depression is one of the widespread diseases whose etiology is still unclear. Dysregulation of the hypothalamic-pituitary-adrenal axis can be the cause of this illness which is concomitant with a high level of cortisol. For this reason, the purpose of the study was to estimate the influence of the selective serotonin reuptake inhibitors (SSRIs) therapy used in monotherapy and polypragmasy on cortisol level in saliva of depressed women. Cortisol was determined in saliva collected from 40 depressed patients treated with SSRIs. HPLC with UV detection was used for quantification of cortisol after its extraction with dichloromethane. For statistical evaluation of the data, the cluster analysis and principal components analysis were used. Results of the study have shown that the SSRIs treatment reduces the cortisol level in saliva. The therapy with sertraline and polypragmasy had a strong influence on suppressing the cortisol secretion. Besides, the amplitude of changes of the cortisol level during the treatment had an impact on the duration of hospitalization. In conclusion, it can be stet that the process of reduction of the cortisol level is multiphasic and that the combination treatment had a stronger influence on suppressing the cortisol secretion than did antidepressants used in monotherapy.

Major depressive disorder and alterations in insular cortical activity: a review of current functional magnetic imaging research

Major depressive disorder (MDD) is characterized by a dysregulated fronto-limbic network. The hyperactivation of limbic regions leads to increased attention and processing of emotional information, with a bias toward negative stimuli. Pathological ruminative behavior is a common symptom of depressive disorder whereby the individual is unable to disengage from internal mental processing of emotionally salient events. In fact, lower deactivations of the neural baseline resting state may account for the increased internal self-focus. The insular cortex, with its extensive connections to fronto-limbic and association areas has recently also been implicated to be a part of this network. Given its wide-reaching connectivity, it has been putatively implicated as an integration center of autonomic, visceromotor, emotional, and interoceptive information. The following paper will review recent imaging findings of altered insular function and connectivity in depressive pathology.

Increased IgA and IgM responses against gut commensals in chronic depression: further evidence for increased bacterial translocation or leaky gut

BACKGROUND

Recently, we discovered that depression is accompanied by increased IgM and IgA responses directed against gram negative gut commensals. The aim of this study was to replicate these findings in a larger study group of depressed patients and to examine the associations between the IgA and IgM responses to gut commensals and staging of depression as well as the fatigue and somatic (F&S) symptoms of depression.

METHODS

We measured serum concentrations of IgM and IgA against the LPS of gram-negative enterobacteria, i.e. Hafnia alvei, Pseudomonas aeruginosa, Morganella morganii, Pseudomonas putida, Citrobacter koseri, and Klebsiella pneumoniae in 112 depressed patients and 28 normal controls. The severity of F&S symptoms was measured using the Fibromyalgia and Chronic Fatigue Syndrome Rating Scale.

RESULTS

The prevalences and median values of serum IgM and IgA against LPS of these commensals were significantly higher in depressed patients than in controls. The IgM levels directed against the LPS of these commensal bacteria were significantly higher in patients with chronic depression than in those without. The immune responses directed against LPS were not associated with melancholia or recurrent depression. There was a significant correlation between the IgA response directed against LPS and gastro-intestinal symptoms.

DISCUSSION

The results indicate that increased bacterial translocation with immune responses to the LPS of commensal bacteria may play a role in the pathophysiology of depression, particularly chronic depression. Bacterial translocation may a) occur secondary to systemic inflammation in depression and intensify and perpetuate the primary inflammatory response once the commensals are translocated; or b) be a primary trigger factor associated with the onset of depression in some vulnerable individuals. The findings suggest that "translocated" gut commensal bacteria activate immune cells to elicit IgA and IgM responses and that this phenomenon may play a role in the pathophysiology of (chronic) depression by causing progressive amplifications of immune pathways.

Metabotropic glutamate 2/3 receptor antagonists improve behavioral and prefrontal dopaminergic alterations in the chronic corticosterone-induced depression model in mice

Metabotropic glutamate 2/3 (mGlu2/3) receptor antagonists have an antidepressant-like effect, but the exact mechanism still remains unclear. This study examined the effects of mGlu2/3 receptor antagonists in chronic corticosterone-treated mice which could be used as an animal model of depression. In the forced swim test, the mGlu2/3 receptor antagonists MGS0039 (1.0 mg/kg, i.p.) and LY341495 (0.3 mg/kg, i.p) significantly reduced the increased immobility time of mice pretreated with corticosterone (20 mg/kg, s.c.) for 21 days, while desipramine (30 mg/kg, i.p.) and fluoxetine (30 mg/kg, i.p.) did not. The antidepressant-like effect of LY341495 was not blocked by the α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptor antagonist NBQX (10 mg/kg, i.p.). Systemic administration of LY341495 did not affect basal release of glutamate, dopamine or serotonin in the prefrontal cortex of the control or chronic corticosterone-treated mice. Chronic corticosterone markedly enhanced high K(+)-induced release of dopamine, but not serotonin or glutamate, in the prefrontal cortex. This neurochemical change was blocked by systemic administration of MGS0039 and LY341495, but not desipramine or fluoxetine. These results suggest that chronic corticosterone-treated mice could be used as an animal model of treatment-resistant depression. This study also suggests that the prefrontal dopaminergic system is involved in the antidepressant-like effect of mGlu2/3 receptor antagonists in the chronic corticosterone-induced depression model.

Hyperstable regulation of vigilance in patients with major depressive disorder

OBJECTIVES

This study tested the hypothesis that patients with depression show less and later declines into lower EEG vigilance stages (different global functional brain states) under resting conditions than healthy controls, as proposed by the vigilance theory of affective disorders.

METHODS

Thirty patients with Major Depressive Disorder (19 female; mean age: 37.2 years, SD: 12.6) without psychotropic medication and 30 carefully age- and sex-matched controls (19 female; mean age: 37.3 years, SD: 12.8) without past or present mental disorders underwent a 15-min resting EEG. EEG-vigilance regulation was determined with a computer-based vigilance classification algorithm (VIGALL, Vigilance Algorithm Leipzig), allowing a classification of vigilance stages A (with substages A1, A2 and A3), B (with substages B1 and B2/3) and C.

RESULTS

Depressive patients spent significantly more time in the highest EEG vigilance substage A1, and less time in substages A2, A3 and B2/3 than controls. In depressive patients, a significantly longer latency until the occurrence of substages A2, A3 and B2/3 was observed. No significant group differences in the percentage of B1 segments or the latency until occurrence of B1 were found.

CONCLUSIONS

The results confirm the hypothesis that patients with depression show less (and later) declines into lower EEG vigilance stages under resting conditions than healthy controls, and support the vigilance theory of affective disorders linking a hyperstable vigilance regulation to depression.

Management of comorbid conditions in heart failure: a review

Multiple comorbidities are common in patients in heart failure. Some of them could contribute to the underlying development of heart failure, whereas others may lead to disease progression and may be associated with poor prognosis. It is not only important to diagnose those comorbid conditions early, but also vital to treat those conditions appropriately, which may have a huge impact on the primary disease itself. The common conditions are discussed in this review, but there are multiple other comorbidities beyond the scope of this article. The physician should try treating "patients as a whole" instead of treating the specific disease, and this approach may require multidisciplinary care.

Differential brain-derived neurotrophic factor expression in limbic brain regions following social defeat or territorial aggression

Syrian hamsters readily form dominant-subordinate relationships under laboratory conditions. Winning or losing in agonistic encounters can have striking, long-term effects on social behavior, but the mechanisms underlying this experience-induced behavioral plasticity are unclear. The present study tested the hypothesis that changes in brain-derived neurotrophic factor (BDNF) may at least in part mediate this plasticity. Male hamsters were paired for 15-min using a resident-intruder model, and individuals were identified as winners or losers on the basis of their behavior. BDNF was examined with in situ hybridization 2 hr after treatment during the consolidation period of emotional learning. Losing animals had significantly more BDNF mRNA in the basolateral (BLA) and medial (MeA) nuclei of the amygdala when compared with winning animals as well as novel cage and home cage controls. Interestingly, winning animals had significantly more BDNF mRNA in the dentate gyrus of the dorsal hippocampus than did losing animals, novel, and home cage controls. No conflict-related changes in BDNF mRNA were observed in several other regions including the bed nucleus of the stria terminalis and central amygdala. Next, we demonstrated that K252a, a Trk receptor antagonist, significantly reduced the acquisition of conditioned defeat when administered within the BLA. These data support a model in which BDNF-mediated plasticity within the BLA supports learning of submission or subordinate social status in losing animals, whereas BDNF-mediated plasticity within the hippocampus may instantiate aspects of winning such as control of a territory in dominant animals.

Depressive symptoms and cortisol rhythmicity predict survival in patients with renal cell carcinoma: role of inflammatory signaling

Purpose

Evidence has supported the association between psychological factors and cancer biology; however, findings are equivocal on the role of psychosocial factors in cancer progression. This study generates a hypothesis of mechanistic variables by examining the clinical effects of psychosocial factors and cortisol dysregulation in patients with metastatic renal cell carcinoma (RCC) and examines associated activation of transcription control pathways.

Methods

Patients with metastatic RCC (n = 217) were prospectively enrolled in this study. Patients completed questionnaires (Centers for Epidemiologic Studies – Depression; SF-36 Health Status Survey; Duke Social Support Index; Coping Operations Preference Enquiry; organized and non-organized religious activity; and intrinsic religiosity), and provided blood and saliva samples. Cortisol levels and whole genome transcriptional profiling were assessed to identify potential alterations in circadian rhythms and genomic pathways.

Results

Separate Cox regression models, controlling for disease risk category, revealed that CES-D scores (p = 0.05, HR = 1.5, 95% CI for HR: 1.00–2.23) and cortisol slope (p = 0.002; HR = 1.9; 95%CI for HR: 1.27–2.97) were significantly associated with decreased survival. Only cortisol slope and risk category remained significant in the complete model. Functional genomic analyses linked depressive symptoms to increased expression of pro-inflammatory and pro-metastatic genes in circulating leukocytes. 116 transcripts were found to be upregulated by an average of 50% or more in high CES-D patients, and 57 transcripts downregulated by at least 50%. These changes were also found in the tumor in a subset of patients.

Conclusion

These findings identify depressive symptoms as a key predictor of survival in renal cell carcinoma patients with potential links to dysregulation of cortisol and inflammatory biology.

Effect of arginine vasopressin on the behavioral activity in the behavior despair depression rat model

Arginine vasopressin (AVP), a nonapeptide posterior hormone of the pituitary, is mainly synthesized and secreted in the hypothalamic paraventricular nucleus (PVN) and supraoptic nucleus (SON). Large numbers of studies have reported that AVP plays a role in depression. The present study was to investigate by which level, brain or periphery, AVP affects the behavioral activity in the behavior despair depression rat model. The results showed that (1) either forced swimming or tail suspension significantly increased AVP concentration not only in the brain (PVN, SON, frontal of cortex, hippocampus, amygdala, lumber spinal cord) but also in the periphery (posterior pituitary and serum); (2) intraventricular injection (icv) of AVP decreased the animal immobility time, whereas V₁ receptor antagonist d(CH₂)₅Tyr(Me)AVP (icv) increased the animal immobility time in a dose-dependent manner not only in FST but also in TST, but the V₂ receptor antagonist d(CH₂)₅[D-Ile, Ile, Ala-NH₉]AVP did not change the animal immobility time in FST or TST; (3) V₁, not V₂ receptor antagonist could inhibit the animal immobility time decrease induced by AVP (icv); (4) neither AVP nor its receptor antagonist (including V₁ and V₂ receptor antagonist) influenced the animal immobility time in both FST and TST. The data suggested that AVP in the brain rather than the periphery played a role in the behavior despair depression by V₁, not V₂ receptors, which behavior despair might have a positive feedback effect on central AVP and blood AVP might have a negative feedback on central AVP in the depressive process.

EEG vigilance regulation patterns and their discriminative power to separate patients with major depression from healthy controls

BACKGROUND/AIM

Recently, a framework has been presented that links vigilance regulation, i.e. tonic brain arousal, with clinical symptoms of affective disorders. Against this background, the aim of this study was to deepen the knowledge of vigilance regulation by (1) identifying different patterns of vigilance regulation at rest in healthy subjects (n = 141) and (2) comparing the frequency distribution of these patterns between unmedicated patients with major depression (MD; n = 30) and healthy controls (HCs; n = 30).

METHOD

Each 1-second segment of 15-min resting EEGs from 141 healthy subjects was classified as 1 of 7 different vigilance stages using the Vigilance Algorithm Leipzig. K-means clustering was used to distinguish different patterns of EEG vigilance regulation. The frequency distribution of these patterns was analyzed in independent data of 30 unmedicated MD patients and 30 matched HCs using a χ² test.

RESULTS

The 3-cluster solution with a stable, a slowly declining and an unstable vigilance regulation pattern yielded the highest mathematical quality and performed best for separation of MD patients and HCs (χ² = 13.34; p < 0.001). Patterns with stable vigilance regulation were found significantly more often in patients with MD than in HCs.

CONCLUSION

A stable vigilance regulation pattern, derived from a large sample of HCs, characterizes most patients with MD and separates them from matched HCs with a sensitivity between 67 and 73% and a specificity between 67 and 80%. The pattern of vigilance regulation might be a useful biomarker for delineating MD subgroups, e.g. for treatment prediction.

Biological indicators of illness risk in offspring of bipolar parents: targeting the hypothalamic-pituitary-adrenal axis and immune system

AIM

The study aims to provide a selective review of the literature pertaining to the hypothalamic-pituitary-adrenal (HPA) axis and immune abnormalities as informative biological indicators of vulnerability in bipolar disorder (BD).

METHOD

We summarize key findings relating to HPA axis and immunological abnormalities in bipolar patients and their high-risk offspring. Findings derive from a review of selected original papers published in the literature, and supplemented by papers identified through bibliography review. Neurobiological findings are discussed in the context of emergent BD in those at genetic risk and synthesized into a neurodevelopmental model of illness onset and progression.

RESULTS

BD is associated with a number of genetic and possibly epigenetic abnormalities associated with neurotransmitter, hormonal and immunologically mediated neurobiological pathways. Data from clinical and high-risk studies implicate HPA axis and immune system abnormalities, which may represent inherited vulnerabilities important for the transition to illness onset. Post-mortem and clinical studies implicate intracellular signal transduction processes and disturbance in energy metabolism associated with established BD. Specifically, long-standing maladaptive alterations such as changes in neuronal systems may be mediated through changes in intracellular signalling pathways, oxidative stress, cellular energy metabolism and apoptosis associated with substantial burden of illness.

CONCLUSIONS

Prospective longitudinal studies of endophenotypes and biomarkers such as HPA axis and immune abnormalities in high-risk offspring will be helpful to understand genetically mediated biological pathways associated with illness onset and progression. A clinical staging model describing emergent illness in those at genetic risk should facilitate this line of investigation.

Chronic non-invasive corticosterone administration abolishes the diurnal pattern of tph2 expression

Both hypothalamic-pituitary-adrenal (HPA) axis activity and serotonergic systems are commonly dysregulated in stress-related psychiatric disorders. We describe here a non-invasive rat model for hypercortisolism, as observed in major depression, and its effects on physiology, behavior, and the expression of tph2, the gene encoding tryptophan hydroxylase 2, the rate-limiting enzyme for brain serotonin (5-hydroxytryptamine; 5-HT) synthesis. We delivered corticosterone (40 μg/ml, 100 μg/ml or 400 μg/ml) or vehicle to adrenal-intact adult, male rats via the drinking water for 3 weeks. On days 15, 16, 17 and 18, respectively, the rats' emotionality was assessed in the open-field (OF), social interaction (SI), elevated plus-maze (EPM), and forced swim tests (FST). On day 21, half of the rats in each group were killed 2h into the dark phase of a 12/12 h reversed light/dark cycle; the other half were killed 2h into the light phase. We then measured indices of HPA axis activity, plasma glucose and interleukin-6 (IL-6) availability, and neuronal tph2 expression at each time point. Chronic corticosterone intake was sufficient to cause increased anxiety- and depressive-like behavior in a dose-dependent manner. It also disrupted the diurnal pattern of plasma adrenocorticotropin (ACTH), corticosterone, and glucose concentrations, caused adrenal atrophy, and prevented regular weight gain. No diurnal or treatment-dependent changes were found for plasma concentrations of IL-6. Remarkably, all doses of corticosterone treatment abolished the diurnal variation of tph2 mRNA expression in the brainstem dorsal raphe nucleus (DR) by elevating the gene's expression during the animals' inactive (light) phase. Our data demonstrate that chronic elevation of corticosterone creates a vulnerability to a depression-like syndrome that is associated with increased tph2 expression, similar to that observed in depressed patients.

REM Sleep Rebound as an Adaptive Response to Stressful Situations

Stress and sleep are related to each other in a bidirectional way. If on one hand poor or inadequate sleep exacerbates emotional, behavioral, and stress-related responses, on the other hand acute stress induces sleep rebound, most likely as a way to cope with the adverse stimuli. Chronic, as opposed to acute, stress impairs sleep and has been claimed to be one of the triggering factors of emotional-related sleep disorders, such as insomnia, depressive- and anxiety-disorders. These outcomes are dependent on individual psychobiological characteristics, conferring even more complexity to the stress-sleep relationship. Its neurobiology has only recently begun to be explored, through animal models, which are also valuable for the development of potential therapeutic agents and preventive actions. This review seeks to present data on the effects of stress on sleep and the different approaches used to study this relationship as well as possible neurobiological underpinnings and mechanisms involved. The results of numerous studies in humans and animals indicate that increased sleep, especially the rapid eye movement phase, following a stressful situation is an important adaptive behavior for recovery. However, this endogenous advantage appears to be impaired in human beings and rodent strains that exhibit high levels of anxiety and anxiety-like behavior.

Testosterone prevents but not reverses anhedonia in middle-aged males and lacks an effect on stress vulnerability in young adults

Middle-aged male rats are more vulnerable than young adult ones to develop anhedonia when exposed to chronic mild stress (CMS). Clinical studies support the idea that in aged subjects the low testosterone (T) levels are related with their higher stress vulnerability and that this hormone possesses antidepressant-like actions. In this study we evaluated the role of gonadal hormones--mainly T--on the depressive-like behavior of middle-aged and young adult male rats submitted to CMS. In middle-aged rats we analyzed the effect of T restitution (at the levels of young adult animals) given 3 weeks before (experiment 1) or 3 weeks after (experiment 2) anhedonia development (indicated by a reduction in sucrose solution intake). T restitution before CMS effectively prevented anhedonia but failed to reverse it once installed. In young adult rats we studied if orchidectomy increased stress vulnerability and found that it failed to modify sucrose intake. These results indicate a stress-dependent differential effect of T in middle-aged rats an age differential role of gonadal hormones on the vulnerability to develop anhedonia. The results suggest that T is a resilience factor in middle-aged but not in young adult males.

Mind matters in cancer survival

OBJECTIVE

The very name "psycho-oncology" implies interaction between brain and body. One of the most intriguing scientific questions for the field is whether or not living better may also mean living longer.

METHODS

Randomized intervention trials examining this question will be reviewed.

RESULTS

The majority show a survival advantage for patients randomized to psychologically effective interventions for individuals with a variety of cancers, including breast, melanoma, gastrointestinal, lymphoma, and lung cancers. Importantly, for breast and other cancers, when aggressive anti-tumor treatments are less effective, supportive approaches appear to become more useful. This is highlighted by a recent randomized clinical trial of palliative care for non-small cell lung cancer patients.There is growing evidence that disruption of circadian rhythms, including rest-activity patterns and hypothalamic-pituitary-adrenal (HPA) axis function, affects cancer risk and progression. Women with metastatic breast cancer have flatter diurnal cortisol patterns than normal, and the degree of loss of daily variation in cortisol predicts earlier mortality. Mechanisms by which abnormal cortisol patterns affect metabolism, gene expression, and immune function are reviewed. The HPA hyperactivity associated with depression can produce elevated levels of cytokines that affect the brain. Tumor cells can, in turn, co-opt certain mediators of inflammation such as NFkB, interleukin-6, and angiogenic factors to promote metastasis. Also, exposure to elevated levels of norepinephrine triggers release of vascular endothelial growth factor, which facilitates tumor growth.

CONCLUSIONS

Therefore, the stress of advancing cancer and management of it is associated with endocrine, immune, and autonomic dysfunction that has consequences for host resistance to cancer progression.

The vasopressin 1b receptor and the neural regulation of social behavior

To date, much of the work in rodents implicating vasopressin (Avp) in the regulation of social behavior has focused on its action via the Avp 1a receptor (Avpr1a). However, there is mounting evidence that the Avp 1b receptor (Avpr1b) also plays a significant role in Avp's modulation of social behavior. The Avpr1b is heavily expressed on the anterior pituitary cortiocotrophs where it acts as an important modulator of the endocrine stress response. In the brain, the Avpr1b is prominent in the CA2 region of the hippocampus, but can also be found in areas such as the paraventricular nucleus of the hypothalamus and the olfactory bulb. Studies that have employed genetic knockouts or pharmacological manipulation of the Avpr1b point to the importance of central Avpr1b in the modulation of social behavior. However, there continues to be a knowledge gap in our understanding of where in the brain this is occurring, as well as how and if the central actions of Avp acting via the Avpr1b interact with the stress axis. In this review we focus on the genetic and pharmacological studies that have implicated the Avpr1b in the neural regulation of social behaviors, including social forms of aggressive behavior, social memory, and social motivation. This article is part of a Special Issue entitled Oxytocin, Vasopressin, and Social Behavior.

Commonality between depression and heart failure

Heart failure (HF) and depression are debilitating diseases with significant effects on functional status and real and perceived quality of life. Despite many advances in therapy for HF mortality remains high. Depression and HF have been recognized to coexist but this does not imply a causative relation. Depressed patients develop more symptoms, have worse compliance with medication regimens, are slower to return to work and social activities, and seem to have a poorer quality of life. In patients with known cardiac disease depression also predicts future events independent of disease severity and other risk factors such as smoking or diabetes mellitus. In conclusion, this review attempts to address the cause/effect relation, if any, between HF and depression and the role of treatment of depression in the setting of HF.

Deprivation of maternal care has long-lasting consequences for the hypothalamic-pituitary-adrenal axis of zebra finches

Early-life stress caused by the deprivation of maternal care has been shown to have long-lasting effects on the hypothalamic-pituitary-adrenal (HPA) axis in offspring of uniparental mammalian species. We asked if deprivation of maternal care in biparental species alters stress responsiveness of offspring, using a biparental avian species--the zebra finch, Taeniopygia guttata. In our experiment, one group of birds was raised by both male and female parents (control), and another was raised by males alone (maternally deprived). During adulthood, offspring of both groups were subjected to two stressors (restraint and isolation), and corticosterone concentrations were measured. Additionally, we measured baseline levels of the two corticosteroid receptors--glucocorticoid receptor (GR) and mineralocorticoid receptor (MR)--in the hippocampus, hypothalamus and cerebellum. Our results suggest that maternally deprived offspring are hyper-responsive to isolation in comparison with controls. Furthermore, mRNA levels of both GR and MR receptors are altered in maternally deprived offspring in comparison with controls. Thus, absence of maternal care has lasting consequences for HPA function in a biparental species where paternal care is available.

Forebrain glutamatergic neurons mediate leptin action on depression-like behaviors and synaptic depression

The glutamatergic system has been implicated in the pathophysiology of depression and the mechanism of action of antidepressants. Leptin, an adipocyte-derived hormone, has antidepressant-like properties. However, the functional role of leptin receptor (Lepr) signaling in glutamatergic neurons remains to be elucidated. In this study, we generated conditional knockout mice in which the long form of Lepr was ablated selectively in glutamatergic neurons located in the forebrain structures, including the hippocampus and prefrontal cortex (Lepr cKO). Lepr cKO mice exhibit normal growth and body weight. Behavioral characterization of Lepr cKO mice reveals depression-like behavioral deficits, including anhedonia, behavioral despair, enhanced learned helplessness and social withdrawal, with no evident signs of anxiety. In addition, loss of Lepr in forebrain glutamatergic neurons facilitates NMDA-induced hippocampal long-term synaptic depression (LTD), whereas conventional LTD or long-term potentiation (LTP) was not affected. The facilitated LTD induction requires activation of the GluN2B subunit as it was completely blocked by a selective GluN2B antagonist. Moreover, Lepr cKO mice are highly sensitive to the antidepressant-like behavioral effects of the GluN2B antagonist but resistant to leptin. These results support important roles for Lepr signaling in glutamatergic neurons in regulating depression-related behaviors and modulating excitatory synaptic strength, suggesting a possible association between synaptic depression and behavioral manifestations of depression.

In search of HPA axis dysregulation in child and adolescent depression

Dysregulation of the hypothalamic–pituitary–adrenal (HPA) axis in adults with major depressive disorder is among the most consistent and robust biological findings in psychiatry. Given the importance of the adolescent transition to the development and recurrence of depressive phenomena over the lifespan, it is important to have an integrative perspective on research investigating the various components of HPA axis functioning among depressed young people. The present narrative review synthesizes evidence from the following five categories of studies conducted with children and adolescents: (1) those examining the HPA system’s response to the dexamethasone suppression test (DST); (2) those assessing basal HPA axis functioning; (3) those administering corticotropin-releasing hormone (CRH) challenge; (4) those incorporating psychological probes of the HPA axis; and (5) those examining HPA axis functioning in children of depressed mothers. Evidence is generally consistent with models of developmental psychopathology that hypothesize that atypical HPA axis functioning precedes the emergence of clinical levels of depression and that the HPA axis becomes increasingly dysregulated from child to adult manifestations of depression. Multidisciplinary approaches and longitudinal research designs that extend across development are needed to more clearly and usefully elucidate the role of the HPA axis in depression.

Beyond pharmacotherapy: understanding the links between obesity and chronic mental illness

While differences in weight-gain potential exist, both between and within classes of psychiatry medications, most commonly used atypical antipsychotics, mood stabilizers, and antidepressants result in some degree of weight gain. This is not new information and it requires an understanding of the tolerability profiles of different treatments and their goodness of fit with specific patient phenotypes. However, this iatrogenic association represents only a piece of this obesity-mental illness dyad. The complex interplay between psychiatric illness and weight involves neurobiology, psychology, and sociological factors. Parsing the salient variables in people with mental illness is an urgent need insofar as mortality from physical health causes is the most common cause of premature mortality in people with chronic mental illness. Our review examines issues associated with common chronic mental illnesses that may underlie this association and warrant further study if we hope to clinically intervene to control this life-threatening comorbidity.

Synthesis and evaluation of potent and selective human V1a receptor antagonists as potential ligands for PET or SPECT imaging

SRX246 is a potent, highly selective human vasopressin V1a antagonist that crosses the blood-brain barrier in rats. CNS penetration makes SRX246 an ideal candidate for potential radiolabeling and use in visualization and characterization of the role of the V1a receptor in multiple stress-related disorders. Before radiolabeling studies, cold reference analogs of SRX246 were prepared. This study describes the synthesis and in vitro screening for human V1a receptor binding and permeability of fluoro, iodo, and methyl reference compounds for SRX246 and the preparation of a tin precursor. For each compound, the potential utility of corresponding radiolabeled analogs for PET and SPECT imaging is discussed.