Immune and hormonal activity in adults suffering from depression

Psychosocial stress and cancer risk: a narrative review

BACKGROUND

It is unclear which psychological factors (stressors, emotional correlates, and psychophysiological markers) induce cancer risk. This currently limits the potential for prevention strategies.

PURPOSE

The aim of this review is to bring forth evidence of stress as a determinant of cancer risk from a public health perspective, written for a broad public of practitioners and scientists.

METHODS

Based on a semisystematic literature search, the impact of different aspects/types of stress and the potential physiological and behavioral pathways are summarized, while highlighting further research, public health and clinical implications.

RESULTS

Between 2007 and 2020, 65 case-control or cohort studies have been identified. Apart from overall cancer ( N = 24), 12 cancer types have been associated with psychological stress with most for breast ( N = 21), colorectal ( N = 11) and lung/prostate/pancreas cancer ( N = 8 each). Although the evidence regarding the mechanisms is still scarce, cancer development in relation to stress might be due to interacting and combined effects of different stress(or) types, but such interaction has not really been tested yet. The path from stress towards cancer incidence consists of a biological pathway with endocrinology and immunology as well as stress-induced behavioral pathways, including smoking, alcoholism, sleep disruption, an unhealthy diet, and low physical activity together with the related phenomenon of obesity.

CONCLUSION

Not only the stress but also the stress-induced lifestyle should be targeted for cancer prevention and treatment. Future research should include a more diverse spectrum of cancer types (not only hormonal related like breast cancer) and of stress measures while also considering behavioral covariates.

The Combination of Sleep Disorders and Depression Significantly Increases Cancer Risk: A Nationwide Large-Scale Population-Based Study

Introduction: Sleep disorders, depression, and cancer have become increasingly prevalent worldwide. However, it is unknown whether coexistence of sleep disorders and depression influences the risk of cancer development. Therefore, we conducted a nationwide population-based study to examine this association among patients in Taiwan. Materials and Methods: A total of 105,071 individuals diagnosed with cancer and 420,284 age- and sex-matched patients without a diagnosis of cancer between 2000 and 2015 were identified from Taiwan’s National Health Insurance Research Database. The underlying chronic diseases of patients that may developed cancer were gathered and studied as the predictor. A multivariate Cox proportional odds model was used to estimate the crude and adjusted odds ratios (aORs) with 95% confidence intervals (CIs) to estimate the interaction effect between sleep disorders and depression on the risk of cancer. Results: After adjusting for age, sex, comorbidities, and other covariates, the cancer group was associated with increased exposure to sleep disorders than the non-cancer group (aOR = 1.440, 95% CI = 1.392−1.489, p < 0.001). In addition, patients with both sleep disorders and depression were at an even higher risk for cancer than the general population (aOR = 6.857, p < 0.001). Conclusions: This retrospective cohort study shows that patients with both sleep disorders and depression are at a higher risk of cancer. Clinically, a meticulous cancer risk evaluation is recommended for patients with both sleep disorders and depression.

Therapeutic effect of fecal microbiota transplantation on chronic unpredictable mild stress-induced depression

Background and objective

Depression is a complex neuropsychiatric disease with extensive morbidity. Its pathogenesis remains unclear, and it is associated with extremely low rates of cure and complete remission. It is vital to study the pathogenesis of depression to develop effective treatments. This study aimed to explore the therapeutic effects and mechanisms of fecal microbiota transplantation (FMT) for the treatment of depression in rats.

Methods

Thirty Sprague-Dawley (SD) rats were randomly divided into three groups: control, chronic unpredictable mild stress (CUMS) to model depression, and CUMS+FMT. For the CUMS and CUMS+FMT groups, after CUMS intervention (four weeks), the rats were given normal saline or FMT (once/week for three weeks), respectively. Behavior, colonic motility, 16S rDNA amplicon sequencing, and untargeted metabolomics on fecal samples were compared between the three rat groups. The following markers were analyzed: 5-hydroxytryptamine (5-HT), gamma-aminobutyric acid (GABA), glutamate (Glu), and brain-derived neurotrophic factor (BDNF) levels in the hippocampus; glucagon-like peptide 1 (GLP-1), lipopolysaccharide (LPS), and interleukin (IL)-6 levels in the serum; and GLP-1, GLP-1 receptor (GLP-1R), and serotonin 4 receptor (5-HT₄R) levels in colonic tissues.

Results

FMT improved symptoms of depression and colonic motility in rats exposed to CUMS. The expression levels of 5-HT, GABA, BDNF, and other biochemical indices, significantly differed among the three groups. Meanwhile, the intestinal microbiota in the CUMS+FMT group was more similar to that of the control group with a total of 13 different fecal metabolites.

Conclusion

FMT exerted antidepressant effects on CUMS-induced depression in rats, and the mechanism involved various neurotransmitters, inflammatory factors, neurotrophic factors, and glucagon-like peptides.

Is the JAK-STAT Signaling Pathway Involved in the Pathogenesis of Depression?

(1) Background: Only 60–70% of depressed patients respond to standard antidepressant treatments. Hence, it is essential to search for new, effective and safe therapies for unmet clinical needs of treatment-resistant depression (TRD). Agents targeting the components of the JAK-STAT signaling pathway have been shown to be relevant in immunology and are commonly used in the treatment of many hematological, rheumatological and dermatological diseases. The aim of this study was to investigate the role of elements of the JAK-STAT signaling pathway in the etiopathogenesis of depressive disorders. (2) Methods: A total of 290 subjects took part in the study (190 depressed patients, 100 healthy controls). Sociodemographic data were collected. The severity of depressive symptoms was assessed using the Hamilton Depression Rating Scale (HDRS). The gene expression at the mRNA protein levels of JAK (JAK1-JAK3) and STAT (STAT1-STAT5) was assessed by using RT-PCR and ELISA. (3) Results: Increased expression of JAK3 and decreased expression of STAT1 were observed in the group of depressed patients. (4) Conclusions: Further studies are necessary to determine whether moderation of the JAK-STAT signaling pathways is involved in the treatment of depression.

Increased Risk of Recurrence of Non-Muscle Invasive Bladder Cancer Associated With Psychological Distress: A Prospective Cohort Study

OBJECTIVE

The primary aim was to evaluate the influence of depressive and anxiety symptoms on the 1-year recurrence rate of non-muscle invasive bladder cancer (NMIBC) patients. The secondary aim was to examine the risk factors leading to psychological distress.

METHODS

A total of 104 NMIBC patients were enrolled for interviews, and the Hospital Anxiety and Depression Scale (HADS) questionnaire survey was administered 1 month after their operation. Their cystoscopy results were followed up. The risk factors affecting their 1-year recurrence rate were evaluated through univariate analysis, Cox regression and Kaplan-Meier analysis. The risk factors causing depressive and anxiety symptoms were evaluated through univariate analysis and logistic regression.

RESULTS

In addition to American Urological Association risk stratification, depressive symptoms were another independent risk factor for recurrence in NMIBC patients (HR: 2.493, 95% CI: 1.048-5.930, p=0.039), and the increase in the recurrence rate was highly significant in intermediate-risk patients (HR: 8.496, 95% CI: 2.178-33.138, p=0.019). Anxiety symptoms were not an independent risk factor for recurrence (HR: 1.655, 95% CI: 0.714-3.837, p=0.240). We also observed that the burden of medical expenses of NMIBC on the family was an independent risk factor for depressive symptoms (p=0.029) and anxiety symptoms (p=0.048); chronic pain was an independent risk factor for anxiety symptoms (OR: 3.447, 95% CI: 1.182-10.052, p=0.023).

CONCLUSION

Depression symptoms are an independent risk factor for recurrence in NMIBC patients. Moreover, the burden of medical expenses on the family is an independent risk factor for depressive and anxiety symptoms in NMIBC patients. Additionally, chronic pain is a risk factor for anxiety symptoms in NMIBC patients. This study provided a theoretical foundation for clinical oncologists to pay more attention to the mental health of NMIBC patients.

Therapeutic potential of mangiferin in the treatment of various neuropsychiatric and neurodegenerative disorders

Xanthones are important chemical class of bioactive products that confers therapeutic benefits. Of several xanthones, mangiferin is known to be distributed widely across several fruits, vegetables and medicinal plants. Mangiferin has been shown to exert neuroprotective effects in both in-vitro and in-vivo models. Mangiferin attenuates cerebral infarction, cerebral edema, lipid peroxidation (MDA), neuronal damage, etc. Mangiferin further potentiate levels of endogenous antioxidants to confer protection against the oxidative stress inside the neurons. Mangiferin is involved in the regulation of various signaling pathways that influences the production and levels of proinflammatory cytokines in brain. Mangiferin cosunteracted the neurotoxic effect of amyloid-beta, MPTP, rotenone, 6-OHDA etc and confer protection to neurons. These evidence suggested that the mangiferin may be a potential therapeutic strategy for the treatment of various neurological disorders. The present review demonstrated the pharmacodynamics-pharmacokinetics of mangiferin and neurotherapeutic potential in several neurological disorders with underlying mechanisms.

Alleviation of Depression by Glucagon-Like Peptide 1 Through the Regulation of Neuroinflammation, Neurotransmitters, Neurogenesis, and Synaptic Function

Depression has emerged as a major cause of mortality globally. Many studies have reported risk factors and mechanisms associated with depression, but it is as yet unclear how these findings can be applied to the treatment and prevention of this disorder. The onset and recurrence of depression have been linked to diverse metabolic factors, including hyperglycemia, dyslipidemia, and insulin resistance. Recent studies have suggested that depression is accompanied by memory loss as well as depressive mood. Thus, many researchers have highlighted the relationship between depressive behavior and metabolic alterations from various perspectives. Glucagon-like peptide-1 (GLP-1), which is secreted from gut cells and hindbrain areas, has been studied in metabolic diseases such as obesity and diabetes, and was shown to control glucose metabolism and insulin resistance. Recently, GLP-1 was highlighted as a regulator of diverse pathways, but its potential as the therapeutic target of depressive disorder was not described comprehensively. Therefore, in this review, we focused on the potential of GLP-1 modulation in depression.

The role of neuroinflammation on pathogenesis of affective disorders

Accumulating evidence suggests that neuroinflammation plays an important role in etiology of psychiatric disorders. Neuronflammation involves a combination of psychological, neuroendocrine, and nervous systems resulting in changes of neurotransmitter metabolism, dysregulation of the hypothalamuspituitary-adrenal axis, pathologic microglial cell activation, impaired neuroplasticity, and structural and functional brain changes affecting cognition and emotional behavior. Inflammatory cytokines have been postulated to be the possible link and culprit in the disruption of these systems. The outcome of any type of dysregulation of the immune system in the brain might lead to occurrence of depression, anxiety. This review focuses on the possible impact of dysregulated cytokine networks which may cause pathogenesis of affective disorders such as depression and anxiety.

Increased risk of prostatitis in male patients with depression

Objectives: To investigate whether male patients with depression are at an increased risk of prostatitis.Methods: We used a universal insurance claims database in Taiwan from 2000 to 2010 to identify patients with newly diagnosed depression (n = 13,019) (depression cohort) and those without depression (n = 53,026) (comparison cohort). Both cohorts were matched by age and index year of depression incidence. Hazard ratios of prostatitis were calculated by multivariable Cox proportional hazard models.Results: The incidence of prostatitis demonstrated a 2-fold increase in the depression cohort in comparison with that observed in the non-depression cohort, with an adjusted hazard ratio of 1.70 after adjustment for age, occupation, urbanisation level, potential comorbidity and medication. Furthermore, patients with depression, relative to the non-depression cohort, were 1.85-fold more likely to develop acute prostatitis, 1.76-fold more likely to develop chronic prostatitis and 1.63-fold more likely to develop unspecific prostatitis. Major associations still existed; even those stratified by age, occupation, urbanisation level and comorbidity all showed greater increased risks of prostatitis in the depression cohort than in the non-depression cohort.Conclusions: Depression can be an independent factor associated with the increased risk of prostatitis for men. The incidence of chronic prostatitis is greater than that of acute prostatitis. Close surveillance for UTI and depression treatment and lifestyle intervention should be considered for men with high risk for prostatitis. The mechanism associated with the development of prostatitis in men with depression requires further study. In addition, the mechanism of prostatitis may need comprehensive investigation.

Modulation of the neurotransmitter systems through the anti-inflammatory and antidepressant-like effects of squalene from Aurantiochytrium sp

Although algae have been the focal point of biofuel research, studies on their biological activities have been limited. In recent years, however, the importance of algae as sources of functional ingredients has been recognized due to their health beneficial effects. In this study, we evaluated the antidepressant-like activities of ethanol extract of Aurantiochytrium sp. (EEA) in the forced swimming test (FST)-induced depression in ICR mice. Imipramine, a commercially available tricyclic antidepressant drug, was used as positive control. Animals were administered EEA orally for 14 consecutive days and were subjected to the locomotor activity testing. Additionally, changes in gene expression in mice brain were assessed by real-time PCR and microarray assays to understand the molecular mechanisms underlying the effect of EEA. We found that the immobility time in FST was significantly reduced in the EEA-treated mice compared to that of in the control mice. Microarray and real-time PCR results revealed that EEA treatment induced changes in several genes in mice brain associated with pro-inflammation and dopaminergic, cholinergic, glutamatergic, and serotonergic synapses. It has previously been reported that several cytokines, such as IL-6 and TNF-α, which mediate neuroinflammation, are also responsible for indirectly altering brain neurotransmitter levels in neuropsychiatric disorders. Therefore, the regulation of the expression of pro-inflammatory genes in EEA-administered mice brain is considered to contribute to the enhancement of neurotransmitter systems-related gene expression in our study. Moreover, our in vitro study suggested that squalene, a component produced by Aurantiochytrium, was one of the active substances in EEA. In conclusion, our study provides the first evidence that Aurantiochytrium sp. can reduce neuroinflammation that may contribute to the modulation of the neurotransmitter systems, which could underlie its antistress and antidepressant effects.

Inflammatory Profiles in Depressed Adolescents Treated with Fluoxetine: An 8-Week Follow-up Open Study

Changes in cytokine levels in major depression and during treatment have been reported in adults. However, few studies have examined cytokine levels in an adolescent sample despite this being a common age of onset. Methods. We measured proinflammatory (IL-2, IFN-γ, IL-1β, TNF-α, IL-6, IL-12, and IL-15) and anti-inflammatory (IL-4, IL-5, IL-13, IL-1Ra, and IL-10) cytokine serum levels in 22 adolescents with major depression and 18 healthy volunteers. Cytokines were measured by multiplex bead-based immunoassays at baseline, and 4 and 8 weeks after commencement of fluoxetine administration in the clinical group. Results. Compared to healthy volunteers, adolescents with major depression at baseline showed significant increases in all pro- and anti-inflammatory cytokines, except IL-1Ra and IL-10. Significant changes were observed in fluoxetine treatment compared to baseline: proinflammatory cytokines IFN-γ, IL-1β, TNF-α, IL-6, IL-12, and IL-15 were decreased only at week 4 whereas IL-2 was increased only at week 8; anti-inflammatory cytokines IL-4 and IL-5 were increased at week 8 while IL-1Ra was reduced only at week 4. There were no significant correlations between cytokine levels and symptomatic improvement in HDRS. Discussion. The results suggest a significant interplay between cytokine levels, the depressive state, and the stage of treatment with an SSRI. To the best of our knowledge, this is the first report in depressed adolescents with elevated IL-12, IL-13, and IL-15 levels. Further studies are necessary to clarify the role and mechanisms of altered cytokine levels in the pathogenesis and physiopathology of major depressive disorder.

C-reactive protein, brain-derived neurotrophic factor, interleukin-2, and stressful life events in drug-naive first-episode and recurrent depression: A cross-sectional study

AIMS

The aim of the study is to assess and compare serum C-reactive protein (CRP), brain derived neurotrophic factor (BDNF), and interleukin-2 (IL-2) levels in patients with first-episode depression (FED), recurrent depressive disorder (RDD), and healthy controls (HCs) and to determine the relationship between the above-specified inflammatory markers, severity of depression, and stressful life events.

MATERIALS AND METHODS

Consecutive drug-naive patients with FED and RDD (n = 85) and 50 HCs were studied. Serum concentrations of CRP, brain-derived nerve growth factor (BDNF), and IL-2 were measured. All participants were assessed using Mini-International Neuropsychiatric Interview Plus, Beck's depression inventory, and presumptive stressful life events scale.

RESULTS

The FED and RDD groups had statistically significant lower serum concentration of BDNF and higher IL-2 compared to the HC group, whereas no statistically significant difference was observed with regard to CRP level. No statistically significant differences were observed with regard to the severity of depression and serum concentrations of CRP, BDNF, and IL-2 in the FED and RDD groups. No significant correlation was found between severity of depression and serum concentration of CRP, BDNF, and IL-2 in both the groups. Serum CRP concentration was significantly higher in patients with ≥2 stressful life events. No significant difference was observed between number of stressful life events and BDNF and IL-2 in patients with depression.

CONCLUSION

FED and RDD are associated with lower serum concentration of BDNF and higher IL-2 compared to the HCs, whereas there appears no difference with regard to CRP level. Multicentric studies are needed to further elucidate the role of inflammatory markers in depression.

Evaluation on monoamine neurotransmitters changes in depression rats given with sertraline, meloxicam or/and caffeic acid

Inflammation drives the development of depression and may affect neurotransmitters and thus neurocircuits increase the risk of depression. To investigate the influence of inhibition of inflammatory pathways on the biogenic amine neurotransmitters metabolism in depressive rats, sertraline, and meloxicam, the inhibitors of arachidonic acid - cyclooxygenase-2/lipoxygenase (AA-COX-2/5-LO) pathways, were given to depressive rats. After the development of depression model by chronic unpredictable mild stress (CUMS) for 6 weeks, Successful modeling rats were selected and randomly divided into CUMS group and medication administration group. After given medicine, The biogenic amine neurotransmitters in rat cortex and hippocampus were measured by high-performance liquid chromatography equipped with an electrochemical detector (HPLC-ECD). Compared with the normal group, the concentration of norepinephrine (NE) significantly decreased and the concentrations of Tyrosine (Tyr), Tryptophan (Trp), 3,4-dihydroxyphenyl acetic acid (DOPAC), 3-methoxy-4-hydroxyphenylglycol (MHPG), homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) significantly increased in the CUMS group. Sertraline significantly inhibited the elevation of 5-HIAA. Meloxicam inhibited the decrease of NE level in CUMS-induced rat and the increase of Trp, MHPG, and 5-HIAA level in a dose-dependent manner. Caffeic acid inhibited the decrease of NE and the increase of Trp and MHPG in a dose-dependent manner. The inhibition of AA-COX-2/5-LO pathways can improve the behaviors of depression rats and suppress CUMS-induced changes in biogenic amines. Compared with the single-dose lipoxygenase (5-LO) or Cyclooxygenase-2 (COX-2) inhibitor, the combination treatment with meloxicam 1 mg/kg and caffeic acid 10 mg/kg have no significant improvement in CUMS-induced depression behavior and the level of cortical monoamine neurotransmitters and their metabolites.

Possible link of Interleukin-6 and Interleukin-2 with psychiatric diagnosis, ethnicity, disaster or BMI

BACKGROUND

Cytokines are of increasing interest as markers for stress responses, mental disorders and general health. We assessed associations of two cytokines with several factors among relocated hurricane survivors and controls.

METHODS

We examined 40 relocated hurricane survivors and 40 demographically matched (frequency matching) Oklahoma controls to assess relationships of Interleukin-2 (IL-2) and Interleukin-6 (IL-6) with psychiatric diagnoses (SCID-IV), demographic variables, hurricane exposure and body mass index (BMI). Participants were predominantly African American (n=70, 87.5%).

RESULTS

Relocated Katrina survivors had higher proportions of current PTSD, major depression and psychiatric diagnoses than controls. Unexpectedly, exposure to Katrina with relocation was not by itself associated with differences in IL-2 or IL-6 levels. The mean IL-2 level was significantly higher in African American participants than other ethnicities (8 Caucasians, 2 Asians) and in those with a current psychiatric disorder. The mean IL-6 level was higher in females than males and in participants with any current psychiatric diagnosis. IL-6 level also correlated positively with participants' BMI.

CONCLUSIONS

Results suggest that cytokines studied were influenced non-specifically by the presence of a mental disorder, and by demographic variables of gender, ethnicity and BMI. Implications of these findings are discussed, as well as possible long-term impact of the identified interleukin differences on immunologic, inflammatory, neuropsychiatric and other systems.

Inhibition of Mammary Cancer Progression in Fetal Alcohol Exposed Rats by β-Endorphin Neurons

BACKGROUND

Fetal alcohol exposure (FAE) increases the susceptibility to carcinogen-induced mammary cancer progression in rodent models. FAE also decreases β-endorphin (β-EP) level and causes hyperstress response, which leads to inhibition of immune function against cancer. Previous studies have shown that injection of nanosphere-attached dibutyryl cyclic adenosine monophosphate (dbcAMP) into the third ventricle increases the number of β-EP neurons in the hypothalamus. In this study, we assessed the therapeutic potential of stress regulation using methods to increase hypothalamic levels of β-EP, a neuropeptide that inhibits stress axis activity, in treatment of carcinogen-induced mammary cancer in fetal alcohol exposed rats.

METHODS

Fetal alcohol exposed and control Sprague Dawley rats were given a dose of N-Nitroso-N-methylurea (MNU) at postnatal day 50 to induce mammary cancer growth. Upon detection of mammary tumors, the animals were either transplanted with β-EP neurons or injected with dbcAMP-delivering nanospheres into the hypothalamus to increase β-EP peptide production. Spleen cytokines were detected using reverse transcription polymerase chain reaction assays. Metastasis study was done by injecting mammary cancer cells MADB106 into jugular vein of β-EP-activated or control fetal alcohol exposed animals.

RESULTS

Both transplantation of β-EP neurons and injection of dbcAMP-delivering nanospheres inhibited MNU-induced mammary cancer growth in control rats, and reversed the effect of FAE on the susceptibility to mammary cancer. Similar to the previously reported immune-enhancing and stress-suppressive effects of β-EP transplantation, injection of dbcAMP-delivering nanospheres increased the levels of interferon-γ and granzyme B and decreased the levels of epinephrine and norepinephrine in fetal alcohol exposed rats. Mammary cancer cell metastasis study also showed that FAE increased incidence of lung tumor retention, while β-EP transplantation inhibited lung tumor growth in both normal and fetal alcohol exposed rats.

CONCLUSIONS

Our results suggest that increase of β-EP production in the hypothalamus may serve as a potential therapeutic strategy for treating the cancer growth in patients with chronic stress and compromised immune function, such as the patients with FAE.

EMDR Therapy in Psycho-Oncology: A Bridge Between Mind and Body

Of the many life-threatening illnesses, cancer can be one of the most traumatic and distressful. It impacts the individual’s sense of identity and interferes with essential features intrinsic to the person’s uniqueness and self-awareness. It attacks patients’ physical integrity, bringing death into the foreground and can directly threaten their sense of belonging to micro and macro social systems. This article stresses the importance of understanding that psychological pain and physical suffering are closely interconnected and, within the context of psycho-oncology, proposes a clinical perspective based on the eye movement desensitization and reprocessing (EMDR) approach, in which the cancer event is nested in the history of life of the patient. EMDR is a therapeutic approach guided by the adaptive information processing (AIP) model. The AIP model postulates that psychopathology results when unprocessed experiences are stored in their own neural network, incapable of connecting with other more adaptive networks. In this perspective, the core of the clinical suffering is hypothesized as embedded in these dysfunctionally suspended memories. In line with recent scientific literature presented in this article, it appears that previous and cancer-related traumas maintain a vicious cycle between psychological and physical health, and the aim of EMDR therapy is to break this cycle. Recent scientific research has hypothesized that EMDR therapy is effective at both the psychological and physical levels. However, because of the consistent heterogeneity of the research design, the findings reported in this article highlight the need for further controlled research for more comprehensive examination.

Possible involvement of the JAK/STAT signaling pathway in N-acetylcysteine-mediated antidepressant-like effects

Advances in depression research have targeted inflammation and oxidative stress to develop novel types of treatment. The JAK/STAT signaling pathway plays pivotal roles in immune and inflammatory responses. The present study was designed to investigate the effects of N-acetylcysteine, a putative precursor of the antioxidant glutathione, in an animal model of depression, with an emphasis on the JAK/STAT signaling pathway. Fluoxetine, a classical antidepressant drug was also under investigation. Male Wistar rats were subjected to forced swimming test and given N-acetylcysteine and fluoxetine immediately after the pre-test session, 5 h later and 1 h before the test session of the forced swimming test. N-acetylcysteine decreased immobility time (P < 0.05), serum corticosterone (P < 0.001), and hydrogen peroxide (P < 0.001), while restored glutathione concentration. Treatment of the rats with N-acetylcysteine produced significant (P < 0.001) down-regulation of STAT3 mRNA expression and protein phosphorylation. On the other hand, N-acetylcysteine significantly (P < 0.001) increased SOCS3 gene expression; however, SOCS3 protein was not changed. In conclusion, our study suggests that modulation of the JAK/STAT pathway might mediate the antidepressant-like effects of N-acetylcysteine. Therefore, depression research may target the JAK/STAT signaling pathway to provide a novel effective therapy.

Depression, Antidepressant Use, and Postmenopausal Breast Cancer Risk

BACKGROUND

Whether depression and antidepressant (AD) use might influence breast cancer risk is unclear, and these exposures have not been evaluated together in a single, prospective cohort study of breast cancer risk.

METHODS

Among 71,439 postmenopausal women in the Women's Health Initiative Observational Study (WHI-OS), we estimated multivariable-adjusted HRs for the independent and joint effects of depressive symptoms and AD use on breast cancer risk using Cox proportional hazards regression.

RESULTS

When analyzed separately, neither depressive symptoms nor AD use at baseline were associated with a significantly increased risk of total breast cancer (HR = 0.96, 95% CI, 0.85-1.08; HR = 1.04, 95% CI, 0.92-1.20, respectively) or invasive breast cancer (HR = 0.98, 95% CI, 0.86-1.12; HR = 1.00, 95% CI, 0.86-1.16, respectively). Current AD use was associated with a borderline-significant increase of in situ breast cancer (HR = 1.30, 95% CI, 0.99-1.75) after adjustment for depressive symptoms; however, this relationship was attenuated after adjustment for mammographic screening (HR = 1.08, 95% CI, 0.76-1.51). No significant variation in total breast cancer risk was observed when the separate and joint effects of depressive symptoms and AD use were explored (P for interaction = 0.14).

CONCLUSION

We found no evidence that either depression or AD use influences breast cancer risk. An elevated risk of in situ disease among AD users could not be ruled out, though is likely due to increased screening in this subgroup.

IMPACT

Given the high prevalence of these exposures, these results may provide reassurance to the millions of women who are depressed and/or use ADs each year.

A Meta-Analysis of Oxidative Stress Markers in Depression

OBJECT

Studies have suggested that depression was accompanied by oxidative stress dysregulation, including abnormal total antioxidant capacity (TAC), antioxidants, free radicals, oxidative damage and autoimmune response products. This meta-analysis aims to analyse the clinical data quantitatively by comparing the oxidative stress markers between depressed patients and healthy controls.

METHODS

A search was conducted to collect the studies that measured the oxidative stress markers in depressed patients. Studies were searched in Embase, Medline, PsychINFO, Science direct, CBMDisc, CNKI and VIP from 1990 to May 2015. Data were subjected to meta-analysis by using a random effects model for examining the effect sizes of the results. Bias assessments, heterogeneity assessments and sensitivity analyses were also conducted.

RESULTS

115 articles met the inclusion criteria. Lower TAC was noted in acute episodes (AEs) of depressed patients (p<0.05). Antioxidants, including serum paraoxonase, uric acid, albumin, high-density lipoprotein cholesterol and zinc levels were lower than controls (p<0.05); the serum uric acid, albumin and vitamin C levels were increased after antidepressant therapy (p<0.05). Oxidative damage products, including red blood cell (RBC) malondialdehyde (MDA), serum MDA and 8-F2-isoprostanes levels were higher than controls (p<0.05). After antidepressant medication, RBC and serum MDA levels were decreased (p<0.05). Moreover, serum peroxide in free radicals levels were higher than controls (p<0.05). There were no differences between the depressed patients and controls for other oxidative stress markers.

CONCLUSION

This meta-analysis supports the facts that the serum TAC, paraoxonase and antioxidant levels are lower, and the serum free radical and oxidative damage product levels are higher than controls in depressed patients. Meanwhile, the antioxidant levels are increased and the oxidative damage product levels are decreased after antidepressant medication. The pathophysiological relationships between oxidative stress and depression, and the potential benefits of antioxidant supplementation deserve further research.

IL-6, IL-18, sIL-2R, and TNFα proinflammatory markers in depression and schizophrenia patients who are free of overt inflammation

Major depressive disorder (MDD) and schizophrenia are associated with inflammatory processes. Studies have shown that these disorders exhibit increase in the level of one or more proinflammatory markers. However, these studies did not exclude patients with obvious inflammation (i.e., CRP>6mg/L). Therefore, a comprehensive study should include those inflammatory disorders. In the present study, the inflammatory natures of MDD and schizophrenia were investigated. To achieve this goal, serum levels of interleukin-6 (IL-6), interleukin-18 (IL-18), tumor necrosis factor alpha (TNFα), and soluble interleukin 2 receptor (sIL-2R) in depressed and schizophrenic patients were obtained and compared with those of the control group. Results showed a significant increase (p<0.05) in serum levels of IL-6, IL-18, TNFα, and sIL-2R in MDD and schizophrenic patients compared with the control group. Also patients with schizophrenia group showed higher levels of the inflammatory markers than MDD and control groups. The current study concluded that the immunological response in the MDD and schizophrenic patients groups was significantly stimulated. These disorders may be considered an inflammatory disorder because of elevated levels of proinflammatory cytokines in spite of lacking an overt inflammation. Furthermore results of this study suggested the possibility of the use of anti-inflammatory drugs as adjuvant therapy in schizophrenic and depressive disorders.

An Act of Balance Between Adaptive and Maladaptive Immunity in Depression: a Role for T Lymphocytes

Historically the monoaminergic neurotransmitter system, in particular the serotonergic system, was seen as being responsible for the pathophysiology of major depressive disorder (MDD). With the advent of psychoneuroimmunology an important role of the immune system in the interface between the central nervous systems (CNS) and peripheral organ systems has emerged. In addition to the well-characterised neurobiological activities of cytokines, T cell function in the context of depression has been neglected so far. In this review we will investigate the biological roles of T cells in depression. Originally it was thought that the adaptive immune arm including T lymphocytes was excluded from the CNS. It is now clear that peripheral naïve T cells not only carry out continuous surveillance within the brain but also maintain neural plasticity. Furthermore animal studies demonstrate that regulatory T lymphocytes can provide protection against maladaptive behavioural responses associated with depression. Psychogenic stress as a major inducer of depression can lead to transient trafficking of T lymphocytes into the brain stimulating the secretion of certain neurotrophic factors and cytokines. The separate and combined mechanism of CD4 and CD8 T cell activation is likely to determine the response pattern of CNS specific neurokines and neurotrophins. Under chronic stress-induced neuroinflammatory conditions associated with depression, T cell responses may become maladaptive and can be involved in neurodegeneration. Additionally, intracellular adhesion and MHC molecule expression as well as glucocorticoid receptor expression within the brain may play a role in determining T lymphocyte functionality in depression. Taken together, T lymphocyte mechanisms, which confer susceptibility or resilience to MDD, are not yet fully understood. Further insight into the cellular and molecular mechanisms which balance the adaptive and maladaptive roles of T lymphocytes may provide a better understanding of both the neuro- degenerative and -regenerative repair functions as present within the neuroimmune network during depression. Furthermore T cells may be important players in restoration of normal behaviour and immune cell homeostasis in depression.

Biomarker approaches in major depressive disorder evaluated in the context of current hypotheses

Major depressive disorder is a heterogeneous disorder, mostly diagnosed on the basis of symptomatic criteria alone. It would be of great help when specific biomarkers for various subtypes and symptom clusters of depression become available to assist in diagnosis and subtyping of depression, and to enable monitoring and prognosis of treatment response. However, currently known biomarkers do not reach sufficient sensitivity and specificity, and often the relation to underlying pathophysiology is unclear. In this review, we evaluate various biomarker approaches in terms of scientific merit and clinical applicability. Finally, we discuss how combined biomarker approaches in both preclinical and clinical studies can help to make the connection between the clinical manifestations of depression and the underlying pathophysiology.

The role of the neuroendocrine and immune systems in the pathogenesis of depression

Development of depression is associated with the body's response to prolonged stress, which adversely affects the functioning of the nervous, endocrine and immune systems. Prolonged stress can lead to the development of a so-called allostatic load and reduction of concentration of brain-derived neurotrophic factor. These changes result in impairment of neurogenesis and synaptic remodeling process. This article illustrates the involvement of key mediators of allostasis such as the neuroendocrine and immune systems, in the pathogenesis of depression. The literature concerning the contribution of the neuroendocrine and immune systems to depression incidence was reviewed. Development of depression is associated with disturbance of the body's allostasis and inflammatory activation of the immune system. It leads to a chronic increase in the concentration of cortisol and proinflammatory cytokines, which results in an allostatic load. This load leads to neurodegeneration, eventually causing irreversible cognitive impairment and permanent disability. Determination of the concentration of chemokines and their receptors is an important indicator of activation of the immune and neuroendocrine systems. The activity of these systems reflects the severity of the disease and provides important information for effective antidepressant treatment.

Immunology of major depression

High levels of several proinflammatory components of the immune system, such as interleukin-6, C-reactive protein, tumor necrosis factor (TNF)-α, or neopterin in patients suffering from major depression (MD) point to the involvement of an inflammatory process in the pathophysiology of MD. The direct and indirect effects of cytokines on neurotransmitter storage and release - mediated by microglia cells and astrocytes - are discussed. The tryptophan/kynurenine metabolism is one of the indirect mechanisms because the enzyme indoleamine 2,3-dioxygenase - a key enzyme of this metabolism in the central nervous system - is driven by pro- and anti-inflammatory cytokines and degrades serotonin. Moreover, neuroactive kynurenines such as kynurenic acid and quinolinic acid act on the glutamatergic neurotransmission as N-methyl-D-aspartate antagonists and agonists, respectively. Alterations of the serotonergic, noradrenergic and glutamatergic neurotransmission have been shown with low-level neuroinflammation and may be involved in symptom generation. Epidemiological and clinical studies show a role for inflammation as a risk factor for MD. A large-scale epidemiological study in MD clearly demonstrates that severe infections and autoimmune disorders are lifetime risk factors for MD. The vulnerability-stress-inflammation model matches with this view as stress may increase proinflammatory cytokines and even contribute to a lasting proinflammatory state. Further support comes from the therapeutic benefit of anti-inflammatory medications such as the cyclo-oxygenase-2 inhibitors, TNF-α antagonists and others, and the anti-inflammatory and immunomodulatory intrinsic effects of antidepressants.

Chronic dim light at night provokes reversible depression-like phenotype: possible role for TNF

The prevalence of major depression has increased in recent decades and women are twice as likely as men to develop the disorder. Recent environmental changes almost certainly have a role in this phenomenon, but a complete set of contributors remains unspecified. Exposure to artificial light at night (LAN) has surged in prevalence during the past 50 years, coinciding with rising rates of depression. Chronic exposure to LAN is linked to increased risk of breast cancer, obesity and mood disorders, although the relationship to mood is not well characterized. In this study, we investigated the effects of chronic exposure to 5 lux LAN on depression-like behaviors in female hamsters. Using this model, we also characterized hippocampal brain-derived neurotrophic factor expression and hippocampal dendritic morphology, and investigated the reversibility of these changes 1, 2 or 4 weeks following elimination of LAN. Furthermore, we explored the mechanism of action, focusing on hippocampal proinflammatory cytokines given their dual role in synaptic plasticity and the pathogenesis of depression. Using reverse transcription-quantitative PCR, we identified a reversible increase in hippocampal tumor necrosis factor (TNF), but not interleukin-1β, mRNA expression in hamsters exposed to LAN. Direct intracerebroventricular infusion of a dominant-negative inhibitor of soluble TNF, XPro1595, prevented the development of depression-like behavior under LAN, but had no effect on dendritic spine density in the hippocampus. These results indicate a partial role for TNF in the reversible depression-like phenotype observed under chronic dim LAN. Recent environmental changes, such as LAN exposure, may warrant more attention as possible contributors to rising rates of mood disorders.

Inflammatory cytokine levels and depressive symptoms in older women in the year after hip fracture: findings from the Baltimore Hip Studies

OBJECTIVES

To determine whether interleukin (IL)-6 or soluble tumor necrosis factor alpha receptor 1 (sTNF-αR1) is associated with depressive symptoms in the year after hip fracture.

DESIGN

Prospective cohort.

SETTING

Three Baltimore-area hospitals.

PARTICIPANTS

Community-dwelling women aged 65 and older admitted with a new, nonpathological fracture of the proximal femur (N = 134).

MEASUREMENTS

Two, 6, and 12 months after fracture, serum was analyzed for IL-6 and sTNF-αR1, and depressive symptoms were measured using the 15-item Geriatric Depression Scale (GDS). Generalized estimating equations were used to model the longitudinal relationship between IL-6, sTNF-αR1, and GDS score. Whether lower extremity function, as measured according to the Lower Extremity Gain Scale (LEGS), explained the relationship between IL-6, sTNF-αR1, and GDS score was also examined.

RESULTS

Participants in the highest categories of IL-6 (≥5.14 pg/mL) and sTNF-αR1 (≥2,421 pg/mL) had the highest GDS scores in the year after fracture (P = .09 for both). Twelve months after fracture, those in the highest IL-6 and sTNF-αR1 categories had GDS scores that were on average 1.9 (95% confidence interval (CI) = 0.4-3.4, P = .01) and 1.4 (95% CI = -0.1-3.0, P = .07) points higher than those in the lowest category, respectively. Adjusting for LEGS score, the mean difference in GDS scores for highest versus lowest IL-6 categories was 1.6 (95% CI = 0.2-3.0, P = .02) points at 12 months.

CONCLUSION

Results from these exploratory analyses support a role for inflammation in the pathophysiology of depressive symptoms after hip fracture. Depressive symptoms in the context of high cytokine levels may represent a sickness syndrome that is chronic in some individuals. Further research should establish the cause and effect of this relationship, as well as long-term correlates.

Assessment of the hypothalamic-pituitary-adrenal axis activity: glucocorticoid receptor and mineralocorticoid receptor function in depression with early life stress - a systematic review

OBJECTIVE

The mechanisms involved in the dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, especially in the functioning of glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) in depressed patients, are not well elucidated. The objective of this study was to conduct a systematic review of articles that assess the HPA axis activity from GR and MR in depressed patients and healthy controls with or without early life stress.

METHODS

We conducted a systematic review of articles in PubMed, SCOPUS and SciELO published between 2000 and 2011, using the following search terms: child abuse, depression, HPA axis, dexamethasone, prednisolone, fludrocortisone and spironolactone. Thirty-four papers were selected for this review.

RESULTS

Most studies identified in this review used the dexamethasone/corticotropin-releasing hormone test and dexamethasone suppression test. In these studies, hypercortisolaemia was associated with depression. We identified three studies with the Prednisolone suppression test, only one study with the use of fludrocortisone and one with spironolactone. This review found nine studies that evaluated the HPA axis in individuals with early life stress.

CONCLUSIONS

The majority of the studies assessed in this review show that early life stress leads to permanent changes in the HPA axis and may lead to development of depression in adults. The most consistent findings in the literature show increased activity of the HPA axis in depression associated with hypercortisolaemia and reduced inhibitory feedback. These findings suggest that this dysregulation of the HPA axis is partially attributable to an imbalance between GR and MR. Evidences have consistently showed that GR function is impaired in major depression, but few studies have assessed the activity of MR in depression and early life stress.

Estresse psicológico e enfrentamento em mulheres com e sem câncer

Considerando o alto índice de mortes de mulheres por cânceres de mama, útero e ovários e resultados de pesquisas indicando relações entre estresse, enfrentamento e doenças como as oncológicas, este estudo investigou, em 30 mulheres com e 30 mulheres sem câncer, a ocorrência de estresse em suas histórias prévias, a importância atribuída ao mesmo e a avaliação de sua superação, nas áreas de saúde, social/trabalho e familiar. Os resultados indicaram relações entre os modos de avaliar e enfrentar o estresse e o adoecimento, sugerindo que padrões mais otimistas e diretos de lidar com o estresse favoreceram a redução de seu impacto no equilíbrio psicofisiológico. Dada a exposição crescente da mulher ao estresse, indica-se a relevância de programas psicoeducativos redutores de seu impacto na população feminina.

Inflammatory biomarkers and depression

Antidepressants, predominantly serotonin- and/or noradrenaline reuptake inhibiting drugs have several shortcomings. The exact pathophysiological mechanisms leading to serotonergic-, noradrenergic- or dopaminergic dysfunction are still unclear. An inflammatory mechanism has been postulated and will be discussed here including possible therapeutic advantages of cyclooxygenase-2 (COX-2) inhibitors. Differences in the activation of the enzyme indoleamine 2,3-dioxygenase (IDO) and in the tryptophan-kynurenine metabolism resulting in an increased tryptophan and serotonin degradation and probably in an increased production of quinolinic acid might play a key role in major depression (MD). These differences are associated with an imbalance in the glutamatergic neurotransmission, which may contribute to an overweight of N-methyl-D: -aspartate agonism in MD. The immunological imbalance results in an increased prostaglandin E₂ production and probably also in an increased COX-2 expression. Although there is strong evidence for the view that the interactions of the immune system, IDO, the serotonergic system and the glutamatergic neurotransmission play a key role in MD, several gaps, e.g. the roles of genetics, disease course, sex, different psychopathological states, etc., have to be bridged by intense further research. There were already hints that anti-inflammatory therapy might have beneficial effects in MD. COX-2 inhibitors, however, have been tested in animal models and in preliminary clinical studies showing favourable effects compared to placebo in MD. The effects of COX-2 inhibition in the CNS as well as the different components of the inflammatory system, the kynurenine-metabolism and the glutamatergic neurotransmission, however, still need careful further scientific evaluation including clinical studies in bigger samples of patients.

A psychoneuroimmunological perspective to Emil Kraepelins dichotomy: schizophrenia and major depression as inflammatory CNS disorders

The Kraepelinian classification of psychiatric disorders, in particular the dichotomy of dementia praecox and manic-depressive psychosis is under discussion since a long time. In recent years, not only new research in the fields of psychopathology and clinical outcome, but also findings of biological markers in the areas of neurophysiology, neuroendocrinology, psychoneuroimmunology, genetics, or psychopharmacology show a big overlap between both groups of disorders. This overlap of symptoms and markers of both disorders intensified the discussion and the proposals for new criteria for the classification of psychiatric disorders. By means of findings from the field of psychoneuroimmunology and inflammation it will be shown that different pathological mechanisms in depression and schizophrenia may lead to the same final common pathway of inflammation. These mechanisms include the immunological balance between type-1 and type-2 immune activation which influences the tryptophan-degradating enzyme indoleamine 2,3-dioxygenase (IDO) in the CNS in opposite ways, leading to an altered availability of tryptophan and serotonin, and a disturbance of the kynurenine metabolism with an imbalance in favor of the production of the NMDA-receptor agonist quinolinic acid in depression and of the NMDA-receptor antagonist kynurenic acid in schizophrenia. In both disorders, however, an increased production of prostaglandin E2 and increased expression of cyclo-oxygenase-2 reflect a slight inflammatory process taking place probably in different regions of the CNS. Albeit this common inflammatory pathway--inflammation is a general pathway of the body as answer to a lot of different noxae and pathogens--the Kraepelinian dichotomy is important with respect to pathological mechanisms and therapeutic approaches, not only for further research in understanding the exact pathological mechanisms but also for the development of preventive strategies in high risk individuals and in patients. Opposite pathways regarding the immune activation, the neurotoxic versus neuroprotective kynurenine metabolites and the agonistic versus antagonistic effects on the NMDA receptor and the glutamatergic neurotransmission show despite a possible therapeutic advantage of anti-inflammatory therapy in both disorders that the Kraepelinian dichotomy still has a significant value from a biologic-psychiatric point of view.

The immune-mediated alteration of serotonin and glutamate: towards an integrated view of depression

Beside the well-known deficiency in serotonergic neurotransmission as pathophysiological correlate of major depression (MD), recent evidence points to a pivotal role of increased glutamate receptor activation as well. However, cause and interaction of these neurotransmitter alterations are not understood. In this review, we present a hypothesis integrating current concepts of neurotransmission and hypothalamus-pituitary-adrenal (HPA) axis dysregulation with findings on immunological alterations and alterations in brain morphology in MD. An immune activation including increased production of proinflammatory cytokines has repeatedly been described in MD. Proinflammatory cytokines such as interleukin-2, interferon-gamma, or tumor necrosis factor-alpha activate the tryptophan- and serotonin-degrading enzyme indoleamine 2,3-dioxygenase (IDO). Depressive states during inflammatory somatic disorders are also associated with increased proinflammatory cytokines and increased consumption of tryptophan via activation of IDO. An enhanced consumption of serotonin and its precursor tryptophan through IDO activation could well explain the reduced availability of serotonergic neurotransmission in MD. An increased activation of IDO and its subsequent enzyme kynurenine monooxygenase by proinflammatory cytokines, moreover, leads to an enhanced production of quinolinic acid, a strong agonist of the glutamatergic N-methyl-D-aspartate receptor. In inflammatory states of the central nervous system, IDO is mainly activated in microglial cells, which preferentially metabolize tryptophan to the NMDA receptor agonist quinolinic acid, whereas astrocytes - counteracting this metabolism due to the lack of an enzyme of this metabolism - have been observed to be reduced in MD. Therefore the type 1/type 2 immune response imbalance, associated with an astrocyte/microglia imbalance, leads to serotonergic deficiency and glutamatergic overproduction. Astrocytes are further strongly involved in re-uptake and metabolic conversion of glutamate. The reduced number of astrocytes could contribute to both, a diminished counterregulation of IDO activity in microglia and an altered glutamatergic neurotransmission. Further search for antidepressant agents should take into account anti-inflammatory drugs, for example, cyclooxygenase-2 inhibitors, might exert antidepressant effects by acting on serotonergic deficiency, glutamatergic hyperfunction and antagonizing neurotoxic effects of quinolinic acid.

Depression, quality of life and breast cancer: a review of the literature

Depression is misdiagnosed and undertreated among breast cancer population. Risk factors for depression in the 5 years after diagnosis are related more to the patient rather than to the disease or its treatment. The breast cancer stage (early and advanced) is not statistically significant in terms of rates of psychosocial distress except for recurrence. Risk factors of depression might impair quality of life such as fatigue, past history or recent episode of depression after the onset of cancer, cognitive attitudes of helplessness/hopelessness, resignation. Body image impairment from mastectomy and sexuality aftermath generates higher rates of mood disorders. The link between increased risk of breast cancer and depression is controversial among the literature. Some studies suggest a protective factor, others find a relation between stress, immunity and cancer occurrence or even mortality. Breast cancer survivors report a higher prevalence of mild to moderate depression with a lower quality of life in all areas except for family functioning. Treatment of depression in breast cancer women improves their quality of life and may increase longevity. Antidepressant medications remain the cornerstone of depression treatment. The hypothetical link between their prescription and increased breast cancer risk is not supported by literature's data.

Serotonergic vulnerability and depression: assumptions, experimental evidence and implications

In recent years, the term serotonergic vulnerability (SV) has been used in scientific literature, but so far it has not been explicitly defined. This review article attempts to elucidate the SV concept. SV can be defined as increased sensitivity to natural or experimental alterations of the serotonergic (5-HTergic) system. Several factors that may disrupt the 5-HTergic system and hence contribute to SV are discussed, including genetic factors, female gender, personality characteristics, several types of stress and drug use. It is explained that SV can be demonstrated by means of manipulations of the 5-HTergic system, such as 5-HT challenges or acute tryptophan depletion (ATD). Results of 5-HT challenge studies and ATD studies are discussed in terms of their implications for the concept of SV. A model is proposed in which a combination of various factors that may compromise 5-HT functioning in one person can result in depression or other 5-HT-related pathology. By manipulating 5-HT levels, in particular with ATD, vulnerable subjects may be identified before pathology initiates, providing the opportunity to take preventive action. Although it is not likely that this model applies to all cases of depression, or is able to identify all vulnerable subjects, the strength of the model is that it may enable identification of vulnerable subjects before the 5-HT related pathology occurs.

Neuroimmune-endocrine crosstalk in schizophrenia and mood disorders

This review focuses on possible causes and the impact of different immune states in schizophrenia and major depression. It discusses the fact that, in schizophrenia, an over-activation of the type 2 immune response may dominate, while the type 1 and the pro-inflammatory immune responses are over-activated in major depression. The consequence of these diverse immune states is the activation and, respectively, inhibition of different enzymes in tryptophan/kynurenine metabolism, which may lead to an overemphasis of N-methyl-D-aspartate (NMDA) receptor antagonism in schizophrenia and of NMDA-receptor agonism in depression, resulting in glutamatergic hypofunction in schizophrenia and glutamatergic hyperfunction in major depression. In addition, the activation of the type 1 and the pro-inflammatory immune responses in major depression result in increased serotonin degradation and a serotonergic deficit. While antipsychotics and antidepressants today mainly act on the dopaminergic-glutamatergic and the noradrenergic-serotonergic neurotransmission, anti-inflammatory and immune-modulating therapies might act more basically at the pathophysiological mechanism. The limitations of this concept, however, are critically discussed.

Stress and depression-induced immune dysfunction: implications for the development and progression of cancer

The persistent activation of the hypothalamic-pituitary-adrenal axis and the sympathetic-adrenal-medullary axes in chronic stress response and in depression impairs the immune response and contributes to the development and progression of some types of cancer. This overview presents results from experimental animal models, human studies, and clinical evidence that various cellular and molecular immunological parameters are compromised in chronic stress and depression. At the cellular level, stressed and depressed patients had overall leukocytosis, high concentrations of circulating neutrophils, reduced mitogen-stimulated lymphocyte proliferation and neutrophil phagocytosis. At the molecular level, high levels of serum basal cortisol, acute phase proteins, specific antibodies against herpes simplex virus type 1 and Epstein Barr virus, plasma concentration of interleukins IL-1, IL-6, and TNF-alpha, and a shift in the balance of Th1 and Th2 immune response were observed. Both stress and depression were associated with the decreased cytotoxic T-cell and natural killer cell activities affecting the processes of the immune surveillance of tumours, and the events that modulate the development and the accumulation of somatic mutations and genomic instability. DNA damage, growth and angiogenic factors, proteases, matrix metalloproteinases, and reactive oxygen species were also related to the chronic stress response and depression. Behavioural strategies, psychological, and psychopharmacotherapeutic interventions that enhance effective coping and reduce affective distress showed beneficial effects in cancer patients. A better understanding of the bidirectional communication between the neuroendocrine and immune systems could contribute to novel clinical and treatment strategies in oncology.

Involvement of fractalkine and macrophage inflammatory protein-1 alpha in moderate-severe depression

Moderate-severe depression (MSD) is linked to overexpression of proinflammatory cytokines and chemokines. Fractalkine (FKN) and macrophage inflammatory protein-1 alpha (MIP-1alpha) are, respectively, members of CX3C and C-C chemokines, and both are involved in recruiting and activating mononuclear phagocytes in the central nervous system. We analysed the presence of FKN and MIP-1alpha in sera of untreated MSD patients and healthy donors. High FKN levels were observed in all MSD patients as compared with values only detectable in 26% of healthy donors. MIP-1alpha was measurable in 20% of patients, while no healthy donors showed detectable chemokine levels. In conclusion, we describe a previously unknown involvement of FKN in the pathogenesis of MSD, suggesting that FKN may represent a target for a specific immune therapy of this disease.

Cytokines and major depression

In the research field of psychoneuroimmunology, accumulating evidence has indicated the existence of reciprocal communication pathways between nervous, endocrine and immune systems. In this respect, there has been increasing interest in the putative involvement of the immune system in psychiatric disorders. In the present review, the role of proinflammatory cytokines, such as interleukin (IL)-1, tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma, in the aetiology and pathophysiology of major depression, is discussed. The 'cytokine hypothesis of depression' implies that proinflammatory cytokines, acting as neuromodulators, represent the key factor in the (central) mediation of the behavioural, neuroendocrine and neurochemical features of depressive disorders. This view is supported by various findings. Several medical illnesses, which are characterised by chronic inflammatory responses, e.g. rheumatoid arthritis, have been reported to be accompanied by depression. In addition, administration of proinflammatory cytokines, e.g. in cancer or hepatitis C therapies, has been found to induce depressive symptomatology. Administration of proinflammatory cytokines in animals induces 'sickness behaviour', which is a pattern of behavioural alterations that is very similar to the behavioural symptoms of depression in humans. The central action of cytokines may also account for the hypothalamic-pituitary-adrenal (HPA) axis hyperactivity that is frequently observed in depressive disorders, as proinflammatory cytokines may cause HPA axis hyperactivity by disturbing the negative feedback inhibition of circulating corticosteroids (CSs) on the HPA axis. Concerning the deficiency in serotonergic (5-HT) neurotransmission that is concomitant with major depression, cytokines may reduce 5-HT levels by lowering the availability of its precursor tryptophan (TRP) through activation of the TRP-metabolising enzyme indoleamine-2,3-dioxygenase (IDO). Although the central effects of proinflammatory cytokines appear to be able to account for most of the symptoms occurring in depression, it remains to be established whether cytokines play a causal role in depressive illness or represent epiphenomena without major significance.

Stress, depression, the immune system, and cancer

The links between the psychological and physiological features of cancer risk and progression have been studied through psychoneuroimmunology. The persistent activation of the hypothalamic-pituitary-adrenal (HPA) axis in the chronic stress response and in depression probably impairs the immune response and contributes to the development and progression of some types of cancer. Here, we overview the evidence that various cellular and molecular immunological factors are compromised in chronic stress and depression and discuss the clinical implications of these factors in the initiation and progression of cancer. The consecutive stages of the multistep immune reactions are either inhibited or enhanced as a result of previous or parallel stress experiences, depending on the type and intensity of the stressor and on the animal species, strain, sex, or age. In general, both stressors and depression are associated with the decreased cytotoxic T-cell and natural-killer-cell activities that affect processes such as immune surveillance of tumours, and with the events that modulate development and accumulation of somatic mutations and genomic instability. A better understanding of the bidirectional communication between the neuroendocrine and immune systems could contribute to new clinical and treatment strategies.

Neuroimmune and cortisol changes in selective serotonin reuptake inhibitor and placebo treatment of chronic posttraumatic stress disorder

BACKGROUND

To explore relations between neuroimmune and neuroendocrine systems relative to posttraumatic stress disorder (PTSD) treatment, cortisol and cytokine changes in response to selective serotonin reuptake inhibitor (SSRI) and placebo treatment of chronic PTSD were assessed prospectively.

METHODS

Baseline measures of PTSD, depression, salivary 8 am and 4 pm cortisol, and serum interleukin-1beta (IL-1beta; pro-inflammatory) and soluble interleukin-2 receptors (IL-2R; cell-mediated immunity) were obtained for 58 PTSD and 21 control subjects. The PTSD subjects participated in a 10-week, double-blind treatment with citalopram (n = 19), sertraline (n = 18), or placebo (n = 7).

RESULTS

At baseline, PTSD subjects had significantly greater PTSD, depression, and IL-1beta and lower IL-2R levels than control subjects, with no group differences found for am or pm cortisol levels. Both SSRI groups' IL-1beta correlated negatively with IL-2R; neither cytokine correlated with cortisol levels. Treatment significantly lowered PTSD, depression, and IL-1beta levels and increased IL-2R for all groups to control subject levels. After treatment, both SSRI groups' IL-1beta correlated with an end cortisol measure (one negatively, one positively).

CONCLUSIONS

Our results support a complex relationship between neuroimmune and neuroendocrine systems with PTSD treatment. Implications of normalization of cytokine levels with effective SSRI treatment and placebo are discussed.

Endobronchial lesions involved in Mycobacterium avium infection

Mycobacterium avium (M. avium) has been described traditionally as an opportunistic organism that causes disseminated disease in the human immunodeficiency virus (HIV)-positive population and that acts as a pulmonary pathogen in patients with underlying lung disease such as chronic obstructive pulmonary disease (COPD) or previously diagnosed tuberculosis. Pulmonary involvement of M. avium may range from asymptomatic colonization of the airway to invasive parenchymal or cavitary disease. However, endobronchial lesions involved in M. avium infection are rare in either immunocompetent or immunosuppressed hosts. We report here endobronchial mycobacterial infection in a HIV-negative patient.