Cytokines as biomarkers in depressive disorder: current standing and prospects

Mendelian randomization analysis reveals causal relationship between depression, antidepressants and benign paroxysmal vertigo

Benign paroxysmal vertigo (BPV) is a common cause of dizziness, and some patients are comorbid with psychiatric disorders such as depression, requiring intervention with antidepressants. However, the causal association between BPV, depression and antidepressants has not been clearly established. We used two-sample bidirectional Mendelian randomization (MR) to analyze the causal association between BPV, depression, and antidepressants. From a Finnish database, 43,280 patients with depression and 329,192 controls, and 106,785 patients with antidepressants and 88,536 controls were selected. Independent single nucleotide polymorphisms (SNPs) for depression and antidepressants were used as instrumental variables (IVs) with genomic significance (p < 5 × 10-8). Similarly, genome-wide association study (GWAS) data for BPV were selected from a Finnish database consisting of 8280 cases and 359,094 controls. Afterwards, a two-sample MR study was performed using R's Two Sample MR and MR-PRESSO software packages. The multiplicity and heterogeneity of the data, as well as the effect of individual SNPs on the results were investigated. The main statistical analyses were weighted median, weighted mode, MR-Egger and weighted inverse variance weighting (IVW) for random effects. Finally, we identified associations between BPV, antidepressants and depression. Four outliers (rs3773087, rs4619804, rs62099231, rs7192848) were found to be associated with depression. After removing the outliers, the statistics showed no heterogeneity (p > 0.05) and horizontal pleiotropy (p > 0.05). Antidepressants were also found to have a random effect IVW (β = 0.440; p = 9.692 × 10-6; OR = 1.553; 95% CI 1.278-1.887). The inverse MR random effects IVW results showed a causal association between BPV and antidepressants (β = 0.051; p = 0.045; OR = 1.052; 95% CI 1.001-1.1066). In conclusion, there was a significant causal association between antidepressants and BPV at the genetic level. Clinicians should pay attention to patients with BPV combined with depressive disorders and develop timely interventions.

The neuroimmune mechanism of pain induced depression in psoriatic arthritis and future directions

Patients suffering from psoriatic arthritis (PsA) often experience depression due to chronic joint pain, which significantly hinders their recovery process. However, the relationship between these two conditions is not well understood. Through a review of existing studies, we revealed that certain neuroendocrine hormones and neurotransmitters are involved in the neuroimmune interactions related to both PsA and depression. These include adrenocorticotropin-releasing hormone (CRH), adrenocorticotropin (ACTH), cortisol, monoamine neurotransmitters, and brain-derived neurotrophic factor (BDNF). Notably, the signalling pathway involving CRH, MCs, and Th17 cells plays a crucial role in linking PsA with depression; thus, this pathway may help clarify their connection. In this review, we outline the inflammatory immune changes associated with PsA and depression. Additionally, we explore how neuroendocrine hormones and neurotransmitters influence inflammatory responses in these two conditions. Finally, our focus will be on potential treatment strategies for patients with PsA and depression through the targeting of the CRH-MC-Th17 pathway. This review aims to provide a theoretical framework as well as new therapeutic targets for managing PsA alongside depression.

IL-17A Mediates Depressive-Like Symptoms by Inducing Microglia Activation in Psoriasiform Dermatitis Mice

BACKGROUND

Psoriasis is recognized as a systemic disease for its accompanying comorbidities, among which psychological disorders present a high incidence rate and affect patients' life quality. Interleukin (IL)-17A is the central pathological factor in the pathogenesis and development of psoriasis.

OBJECTIVE

To clarify if psoriasis-induced systemic IL-17A increase can mediate the neuronal inflammation and result in depressive-like symptoms.

METHODS

Psoriasiform dermatitis model was established by imiquimod (IMQ) application on male BALB/c mice and IL-17A intervention was performed by lateral ventricular catheterization. Skin structural, histopathological characteristics, and behavioral tests were assessed. Serum IL-17A levels were detected by Enzyme-linked immunosorbent assay. mRNA expression of pro-inflammatory factors IL-1β, IL-6, and tumor necrosis factor-α (TNF-α) as well as anti-inflammatory factors IL-4 and IL-10 in the hippocampus and cortex were measured by RT-qPCR. The number of microglia and hippocampal neurons was quantified by immunofluorescent assay.

RESULTS

IMQ treatment resulted in significant skin structural and histopathological characters of psoriasiform dermatitis with elevated serum IL-17A levels, obvious depressive-like behaviors, microglia activation with increased IL-1β, IL-6, and TNF-α expression levels in the hippocampus and cortex, and notable inhibition of hippocampal neurogenesis. While, IL-17A neutralization by intracerebroventricular injection of anti-IL-17A antibody can remarkably inhibit microglia activation and decrease the abnormally increased expression levels of IL-1β, IL-6, and TNF-α in the hippocampus and cortex of psoriasiform dermatitis mice, promote hippocampal neurogenesis, thus alleviate the depressive-like behaviors.

CONCLUSION

In the pathological condition of psoriasis, systemic IL-17A elevation can trigger microglia activation, provoke pro-inflammation mediators to release, evoke neuroinflammation, subsequently inhibit hippocampal neurogenesis, and result in depression. IL-17A, as an important pathogenic factor in psoriasis, contributes to its critical role in mediating systemic inflammation and depression comorbidity.

Cytokine and Microbiome Changes in Adolescents with Anorexia Nervosa at Admission, Discharge, and One-Year Follow-Up

Anorexia nervosa (AN) is a severe eating disorder that predominantly affects females and typically manifests during adolescence. There is increasing evidence that serum cytokine levels are altered in individuals with AN. Previous research has largely focused on adult patients, assuming a low-grade pro-inflammatory state. The serum levels of the cytokine tumour necrosis factor-alpha (TNF-α), interleukin (IL)-1β, IL-6 and IL-15, which are pro-inflammatory, were examined in 63 female adolescents with AN and 41 age-matched healthy controls (HC). We included three time points (admission, discharge, and 1-year follow-up) and investigated the clinical data to assess whether the gut microbiota was associated with cytokine alterations. Relative to the HC group, serum levels of IL-1β and IL-6 were significantly lower during the acute phase (admission) of AN. IL-1β expression was normalised to control levels after weight recovery. TNF-α levels were not significantly different between the AN and HC groups. IL-15 levels were significantly elevated in patients with AN at all time points. We found associations between cytokines and bodyweight, illness duration, depressive symptoms, and the microbiome. In contrast to most findings for adults, we observed lower levels of the pro-inflammatory cytokines IL-1β and IL-6 in adolescent patients, whereas the level of IL-15 was consistently increased. Thus, the presence of inflammatory dysregulation suggests a varied rather than uniform pro-inflammatory state.

Latent profile analysis of depression in US adults with obstructive sleep apnea hypopnea syndrome

Objective

This study used latent profile analysis to explore the level of depression among US adults with obstructive sleep apnea hypopnea syndrome (OSAHS) symptoms and to identify different latent categories of depression to gain insight into the characteristic differences between these categories.

Methods

The data of this study were obtained from the National Health and Nutrition Examination Survey (NHANES) database, and the subjects with OSAHS symptoms were aged 18 years and older. The latent profile analysis (LPA) method was used to fit the latent depression categories in subjects with OSAHS symptoms. The chi-square test, rank sum test, and binary logistic regression were used to analyze the influencing factors of depression subgroups in subjects with OSAHS symptoms.

Results

Three latent profiles were identified: low-level (83.7%), moderate-level (14.5%) and high-level (1.8%) depression. The scores of 9 items in the high-level depression group were higher than those in the other two groups. Among them, item 4 "feeling tired or lack of energy" had the highest score in all categories.

Conclusion

Depression in subjects with OSAHS symptoms can be divided into low-level, moderate-level and high-level depression. There are significant differences among different levels of depression in gender, marital status, PIR, BMI, smoking, general health condition, sleep duration and OSAHS symptom severity.

Long-Term Immunomodulatory Impact of VNS on Peripheral Cytokine Profiles and Its Relationship with Clinical Response in Difficult-to-Treat Depression (DTD)

Vagus nerve stimulation (VNS) represents a long-term adjunctive treatment option in patients with difficult-to-treat depression (DTD). Anti-inflammatory effects have been discussed as a key mechanism of action of VNS. However, long-term investigations in real-world patients are sparse. In this naturalistic observational study, we collected data on cytokines in peripheral blood in n = 6 patients (mean age 47.8) with DTD and VNS treatment at baseline and at 6 months follow-up. We have identified clusters of peripheral cytokines with a similar dynamic over the course of these 6 months using hierarchical clustering. We have investigated cytokine changes from baseline to 6 months as well as the relationship between the cytokine profile at 6 months and long-term response at 12 months. After 6 months of VNS, we observed significant correlations between cytokines (p < 0.05) within the identified three cytokine-pairs which were not present at baseline: IL(interleukin)-6 and IL-8; IL-1β and TNF-α; IFN-α2 and IL-33. At 6 months, the levels of all the cytokines of interest had decreased (increased in non-responders) and were lower (5-534 fold) in responders to VNS than in non-responders: however, these results were not statistically significant. VNS-associated immunomodulation might play a role in long-term clinical response to VNS.

Mechanisms for the biological activity of Gastrodia elata Blume and its constituents: A comprehensive review on sedative-hypnotic, and antidepressant properties

BACKGROUND

Insomnia and depressive disorder are two common symptoms with a reciprocal causal relationship in clinical practice, which are usually manifested in comorbid form. Several medications have been widely used in the treatment of insomnia and depression, but most of these drugs show non-negligible side effects. Currently, many treatments are indicated for insomnia and depressive symptom, including Chinese herbal medicine such as Gastrodia elata Blume (G. elata), which has excellent sedative-hypnotic and antidepressant effects in clinical and animal studies.

PURPOSE

To summarize the mechanisms of insomnia and depression and the structure-activity mechanism for G. elata to alleviate these symptoms, particularly by hypothalamic-pituitary-adrenal (HPA) axis and intestinal flora, aiming to discover new approaches for the treatment of insomnia and depression.

METHODS

The following electronic databases were searched from the beginning to November 2023: PubMed, Web of Science, Google Scholar, Wanfang Database, and CNKI. The following keywords of G. elata were used truncated with other relevant topic terms, such as depression, insomnia, antidepressant, sedative-hypnotic, neuroprotection, application, safety, and toxicity.

RESULTS

Natural compounds derived from G. elata could alleviate insomnia and depressive disorder, which is involved in monoamine neurotransmitters, inflammatory response, oxidative stress, and gut microbes, etc. Several clinical trials showed that G. elata-derived natural compounds that treat depression and insomnia have significant and safe therapeutic effects, but further well-designed clinical and toxicological studies are needed.

CONCLUSION

G. elata exerts a critical role in treating depression and insomnia due to its multi-targeting properties and fewer side effects. However, more clinical and toxicological studies should be performed to further explore the sedative-hypnotic and antidepressant mechanisms of G. elata and provide more evidence and recommendations for its clinical application. Our review provides an overview of G. elata treating insomnia with depression for future research direction.

Anorexia Nervosa in vivo cytokine production: a systematic review

INTRODUCTION

The underlying psychobiology that contributes to Anorexia Nervosa (AN) onset and disease progression remains unclear. New research is emerging suggesting a possible link between inflammation and a variety of mental illnesses. Alterations of cytokines may play a role in the pathogenesis of AN. Some studies have found differences in the cytokine profile of those with AN compared to healthy controls, but results are heterogeneous. The aim of this work was to systematically review existing studies investigating in-vivo cytokine production in those with AN before and after weight restoration compared to controls.

METHODS

A comprehensive literature search of four electronic databases (PubMed, PsychInfo, EMBASE and CINAH) was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines to identify human in-vivo studies investigating the relationship between AN and cytokine production. Data extracted from included studies related to population characteristics (e.g. age, gender, mean mBMI/%IBW), cytokine measurement and relevant findings. Confounding factors (e.g. smoking status, co-morbid mental illness, menstruation status) were also collected.

RESULTS

36 studies were eligible for this systematic review of which the majority were conducted in Europe (77.8%) and involved female subjects (97.2%). Those with AN ranged in age from 13 to 47 years and had an illness duration of 3 months to 24 years. 15 candidate cytokines and 3 receptors were identified (TNF-alpha, IL-6, IL-1B, CRP, IL-2, IL-7, IL-10, IFN-γ, TNF-R2, IL-1 α, IL-15, TNF-R1, IL-17, IL-18, TGF-B1, IL-12, IL-6R and TGF-B2) exploring in-vivo levels in patients with AN and comparing to controls. TNF-alpha and IL-6 were the most extensively studied with IL-6 being significantly elevated in 4 out of 8 (50%) of longitudinal studies when comparing AN patients at baseline compared to post weight restoration. Following weight restoration, there was no difference in IL-6 levels when comparing to HC in 7 of 8 (87.5%) longitudinal studies examined.

CONCLUSIONS

The most promising cytokine potentially involved in the pathogenesis of AN appears to be IL-6, and possibly TNF-alpha pathways. The heterogeneity of clinical and methodology factors impedes the generalizability of results. Future studies may wish to address these methodological shortcomings as alterations in cytokine levels in AN could act as therapeutic targets assisting with weight restoration and psychopathology and may offer diagnostic potential.

Cytokine associated with severity of depressive symptoms in female nurses in Korea

Background

Depression has been associated with the risk of developing physical illnesses and diseases. Inflammatory hypotheses of immunoactive and dysregulated cytokine production have been proposed to describe this association; however, data pertaining to the high prevalence of depression among nurses are limited.

Objective

This study aimed to use a comprehensive immune-profiling approach to determine whether an abnormal profile of circulating cytokines could be identified in nurses with self-reported depression and whether this profile is associated with the severity of depression.

Methods

We investigated a cohort of 157 female nurses in Korea. The self-report Patient Health Questionnaire was used to measure the depression levels of nurses. In addition, peripheral blood samples were collected and used to measure the cytokine profile using the Luminex multiplexing system. Generalized gamma regression analyses were conducted to evaluate the association between cytokine and depressive symptoms.

Results

Regarding severity of depressive symptoms, 28.0% of nurses had moderately severe depression while 9.6% had severe depression. Moderately-severe depressive symptoms in nurses were associated with elevated levels of interleukin-6 (B = 0.460, p = 0.003), interleukin-8 (B = 0.273, p = 0.001), and interleukin-18 (B = 0.236, p = 0.023), whereas interferon-gamma levels (B = -0.585, p = 0.003) showed the opposite profile. Participants with severe depressive symptoms presented decreased interferon-gamma levels (B = -1.254, p < 0.001).

Conclusion

This study demonstrated that proinflammatory cytokines were associated with depression among nurses. This calls for early detection and intervention, considering the mechanisms linking depression to physical illness and disease.

Enlarged cross-sectional area of the left vagus nerve in patients with major depressive disorder

Purpose

Autonomic dysfunction and a chronic low-grade inflammation are supposed to play a role in the etiology of major depressive disorder (MDD). The vagus nerves (VN) form a major part of the parasympathetic nervous system and of the gut-brain axis. They are supposed to exert anti-inflammatory and epithelial barrier protective effects in the gut. A reduced vagal activity was described in patients with MDD. We aimed to examine the VN in patients with MDD with high-resolution ultrasound (HRUS) and hypothesized that the cross-sectional area (CSA) and the echogenicity of the VNs were altered in comparison to healthy controls.

Materials and methods

The echogenicity (gray scale mean) and the CSA of the cervical VNs at the level of the thyroid gland and both median nerves were examined with HRUS in 50 patients with MDD and 50 matched healthy controls.

Results

The left VN-CSA was significantly larger in the MDD group compared to the control group (1.7 ± 0.4 mm2 versus 1.5 ± 0.4 mm2; p = 0.045). The CSA of the right VN and both median nerves (MN) were similar between groups. In MDD subgroup analyses, recurrent depressive disorders were the main contributing factor for the left VN-CSA enlargement. Echogenicity was not altered in the VN and MN between groups.

Conclusion

The enlargement of the left VN-CSA in patients with MDD, and especially in these patients with recurrent depressive disorders, might turn out as a promising imaging biomarker. Longitudinal studies are warranted to examine whether the VNs-CSA change in the course of MDD.

Possible involvement of microglial P2RY12 and peripheral IL-10 in postpartum depression

Postpartum depression (PPD) is another type of depression, including emotional fluctuation, fatigue, and anxiety. Based on the specific event like giving birth, it can be speculated that PPD might have its specific mechanism. Here, we confirmed that dexamethasone (DEX) administration during pregnancy (gestational days 16-18) induced depressive- and anxiety-like behaviors in dam (DEX-dam) after weaning period (3 weeks). DEX-dam showed anxiety-like behaviors in open-field test (OFT) and light-dark test (LD). In addition, DEX-dam exhibited depressive-like behaviors with the increased immobility time in forced swimming test (TST). Molecular analysis confirmed that microglia, rather than neurons, astrocytes, and oligodendrocytes, are involved in anxiety-/depressive-like behaviors. Notably, P2ry12, homeostatic gene, and purinoceptor, along with hyper-ramified form, were reduced in the hippocampus of DEX-dam. In addition, we found that IL-10 mRNA was reduced in lymph nodes without alteration of pro-inflammatory cytokines, such as TNF-α, IL-1β, and IL-6. Interestingly, anxiety-/depressive-like behaviors of DEX-dam were restored with the normalization of P2ry12 and IL-10 after 10 weeks postpartum without antidepressants. Our results propose that stress hormone elevation during pregnancy might be associated with PPD via microglial P2RY12 and peripheral IL-10.

Novel ketamine and zinc treatment for anorexia nervosa and the potential beneficial interactions with the gut microbiome

Anorexia nervosa (AN) is a severe illness with diverse aetiological and maintaining contributors including neurobiological, metabolic, psychological, and social determining factors. In addition to nutritional recovery, multiple psychological and pharmacological therapies and brain-based stimulations have been explored; however, existing treatments have limited efficacy. This paper outlines a neurobiological model of glutamatergic and γ-aminobutyric acid (GABA)-ergic dysfunction, exacerbated by chronic gut microbiome dysbiosis and zinc depletion at a brain and gut level. The gut microbiome is established early in development, and early exposure to stress and adversity contribute to gut microbial disturbance in AN, early dysregulation to glutamatergic and GABAergic networks, interoceptive impairment, and inhibited caloric harvest from food (e.g., zinc malabsorption, competition for zinc ions between gut bacteria and host). Zinc is a key part of glutamatergic and GABAergic networks, and also affects leptin and gut microbial function; systems dysregulated in AN. Low doses of ketamine in conjunction with zinc, could provide an efficacious combination to act on NMDA receptors and normalise glutamatergic, GABAergic and gut function in AN.

Earlier age of onset is associated with a pro-inflammatory state in major depressive disorder

Major depressive disorder (MDD) is a common condition that affects the general population over a wide range of ages, regardless of gender and social background. Early-onset of MDD in adulthood, between ages of 18 and 30 years, is associated with worse outcomes and increased years of disability. Stress load and physical health have been associated with age of onset in MDD. We aim to investigate whether early onset MDD might be associated with changes in systemic inflammatory markers. We examined levels of following cytokines: IL-1β, IL-6, IL-10 and TNFα in 234 patients with MDD. Higher serum levels of TNFα and IL-1β are associated with the early onset of the disorder in patients with MDD. IL-6 levels were also higher in the early onset group and IL-10 levels were higher in the late onset group, but with no significant difference. Changes in the anti-inflammatory/pro-inflammatory balance have been described in mood disorders and may be implicated in its severity and pattern of progression. Our findings reinforce that higher serum levels of IL-1β and TNFα may be associated with the earlier onset subgroup of MDD patients. Future research that target inflammatory markers of immune modulation may be, key in the search for novel preventative therapeutics.

LOWER ANTIDEPRESSANT RESPONSE TO FLUOXETINE IS ASSOCIATED WITH ANXIETY-LIKE BEHAVIOR, HIPPOCAMPAL OXIDATIVE IMBALANCE, AND INCREASE ON PERIPHERAL IL-17 AND IFN-γ LEVELS

Major depression is a leading contributor to the global burden of disease. This is mainly related to the disorder chronic and recurrent nature, and to high rates of refractoriness to treatment. Limited efficacy with currently available antidepressants highlights the need for more effective options for treating drug-resistant patients and emphasizes the importance of developing specific preclinical models for treatment-resistant populations. Treatment-resistant depression (TRD) is commonly defined as failure to respond to two or more trials of antidepressants. In this study, we investigated the effect of fluoxetine treatment for fourteen days on the depressive-like behavior and the oxidative and inflammatory parameters of mice submitted to chronic corticosterone administration. After 21 days of subcutaneous corticosterone administration (20mg/Kg/day) and 14 days of oral fluoxetine treatment (10mg/Kg/day, started on day 7 of induction protocol), we separated animals into two groups according to the tail suspension test's (TST) results: antidepressant responders (good response to antidepressant, GRA) and non-responders (resistance to antidepressant, AR). Forced swimming test (FST), elevated plus maze test (EPMT), and open field test (OFT) were performed. We found that animals classified as AR (i.e., those with higher immobility values in the TST) demonstrated anxiety-like behavior in the EPMT, increased H₂O₂ levels, and decreased catalase activity in the hippocampus, as well as increased serum levels of IL-17 and IFN-γ. Our findings suggest that a redox imbalance in the hippocampus, combined with increased levels of peripheral IL-17 and INF-γ, may be involved with an impaired response to fluoxetine.

Profiling classical neuropsychiatric biomarkers across biological fluids and following continuous lumbar puncture: A guide to sample type and time

Identification of putative biomarkers for neuropsychiatric disorders has produced a diverse list of analytes involved in inflammation, hypothalamic–pituitary–adrenal axis (HPA) regulation, growth factor and metabolic pathways. However, translation of these findings to accurate and robust assays has been stalled, affecting objective diagnoses, tracking relapse/remission, and prediction/monitoring of drug affect. Two important factors to control are the sample matrix (e.g. serum, plasma, saliva, or cerebrospinal fluid) and time of sample collection. Additionally, sample collection procedures may affect analyte level. In this study, a panel of 14 core neuropsychiatric biomarkers was measured in serum, plasma, saliva, and cerebrospinal fluid (CSF), all collected from 8 healthy volunteers at the same time. In a second cohort of 7 healthy volunteers, 6 analytes were measured in serum and CSF collected at 13 timepoints over a 24-h period after catheter placement. We found that many of the analytes were quantifiable in all sample types examined, but often at quite different concentrations and without correlation between the sample types. After catheter placement, a diurnal pattern was observed for cortisol and interleukin-6 in serum, and transient spikes were observed in interleukin-1β. In CSF, a chronic elevation of several cytokines was observed instead, perhaps due to the continuous sampling procedure. These findings enable more informed decision-making around sample type and collection time, which can be implemented in future biomarker studies.

Clinicaltrial.gov identifiers

NCT02933762, NCT02475148.

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Diurnal pattern for cortisol, interleukin (IL)-6 and transient spikes for IL-1β were observed

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Chronic elevation of cytokines observed may be due to continuous sampling procedure

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Informed decision-making around sample types and collection time can be implemented

Prenatal stress, anxiety and depression alter transcripts, proteins and pathways associated with immune responses at the maternal-fetal interface†

During pregnancy, the immune system is modified to allow developmental developmental tolerance of the semi-allogeneic fetus and placenta to term. Pregnant women suffering from stress, anxiety and depression show dysfunctions of their immune system that may be responsible for fetal and/or newborn disorders, provided that provided that placental gene regulation is compromised. The present study explored the effects of maternal chronic self-perceived stress, anxiety and depression during pregnancy on the expression of immune related-genes and pathways in term placenta. Pregnancies were clinically monitored with the Beck's Anxiety Inventory (BAI) and Edinburgh Postnatal Depression Scale (EPDS). A cutoff threshold for BAI/EPDS of 10 divided patients into two groups: Index group (≥10, n = 11) and a Control group (<10, n = 11), whose placentae were sampled at delivery. The placental samples were subjected to RNA-Sequencing, demonstrating that stress, anxiety and depression during pregnancy induced a major downregulation of placental transcripts related to immune processes such as T-cell regulation, interleukin and cytokine signaling or innate immune responses. Expression differences of main immune related genes such as CD46, CD15, CD8α & β ILR7α and CCR4 among others, were found in the index group (P < 0.05). Moreover, the key immune-like pathway involved in humoral and cellular immunity named "Primary immunodeficiency" was significantly downregulated in the index group compared to controls. Our results show that mechanisms ruling immune system functions are compromised at the maternal-fetal interface following self-perceived depressive symptoms and anxiety during pregnancy. These findings may help unveil mechanisms ruling the impact of maternal psychiatric symptoms and lead to new prevention/intervention strategies in complicated pregnancies.

Impact of comorbid post traumatic stress disorder on multiple sclerosis in military veterans: A population-based cohort study

BACKGROUND

Very little is known regarding the impact of post traumatic stress disorder (PTSD) on the course of multiple sclerosis (MS).

OBJECTIVES

To explore the impact of pre-existing PTSD on MS relapses, magnetic resonance imaging (MRI) activity, and disability in a large population-based cohort.

METHODS

Military Veterans with MS and PTSD prior to symptom onset (MS_PTSD, n = 96) were identified using the Department of Veterans Affairs MS databases. MS_PTSD cases were matched to MS controls without PTSD (n = 95). Number of relapses, number of new T2 lesions and new gadolinium lesions on brain MRI, and neurological disability were abstracted between 2015 and 2019.

RESULTS

The mean annualized relapse rate was greater in the MS_PTSD group versus controls (0.23 vs 0.06, respectively; p < 0.05), as was the annualized mean number of new T2 and gadolinium-enhancing lesions on brain MRI (0.52 vs 0.16 and 0.29 vs 0.08, respectively; p < 0.05). Disability accrual (time to Disability Status Scale 6.0) was more rapid (23.7 vs 29.5 years, p < 0.05) in relapsing MS patients with PTSD.

CONCLUSION

Patients with MS_PTSD have higher disease activity and reach disability endpoints more rapidly than controls. This is the first study to show PTSD as a potentially modifiable risk factor for MS relapses, MRI activity, and disability.

Histamine H3 Receptor Ligands-KSK-59 and KSK-73-Reduce Body Weight Gain in a Rat Model of Excessive Eating

Noting the worldwide rapid increase in the prevalence of overweight and obesity new effective drugs are now being sought to combat these diseases. Histamine H₃ receptor antagonists may represent an effective therapy as they have been shown to modulate histamine synthesis and release and affect a number of other neurotransmitters (norepinephrine, acetylcholine, γ-aminobutyric acid, serotonin, substance P) thus influencing the food intake. Based on the preliminary studies determining affinity, intrinsic activity, and selected pharmacokinetic parameters, two histamine H₃ receptor ligands were selected. Female rats were fed palatable food for 28 days and simultaneously administered the tested compounds intraperitoneally (i.p.) at a dose of 10 or 1 mg/kg b.w./day. Weight was evaluated daily and calorie intake was evaluated once per week. The plasma levels of cholesterol, triglycerides, leptin, adiponectin, ghrelin, corticosterone, CRP and IL-6 were determined at the end of experiment. The glucose tolerance test was also performed. To exclude false positives, the effect of tested compounds on spontaneous activity was monitored during the treatment, as well as the amount of consumed kaolin clay was studied as a reflection of possible gastrointestinal disturbances comparable to nausea. The histamine H₃ receptor antagonists KSK-59 and KSK-73 administered i.p. at a dose of 10 mg/kg b.w. prevented weight gain in a rat model of excessive eating. They reduced adipose tissue deposits and improved glucose tolerance. Both compounds showed satisfying ability to penetrate through biological membranes determined in in vitro studies. Compound KSK-73 also reduced the caloric intake of the experimental animals what indicates its anorectic effect. These results show the pharmacological properties of histamine H₃ receptor antagonists, (4-pyridyl)piperazine derivatives, as the compounds causing not only slower weight gain but also ameliorating some metabolic disorders in rats having the opportunity to overeat.

Faster speed of onset of the depressive episode is associated with lower cytokine serum levels (IL-2, -4, -6, -10, TNF-α and IFN-γ) in patients with major depression

INTRODUCTION

Cytokines might play a key role in the pathophysiology of major depressive disorder (MDD). The speed of onset of depressive episodes has been discussed as an important clinical parameter in MDD. The aim of this study was to investigate a potential influence of the speed of onset of the depressive episode on cytokine serum levels.

METHOD

Serum level of the cytokines interleukin (IL)-2, IL-4, IL-6, IL-8, IL-10, tumor necrosis factor alpha (TNF-α), interferon-gamma (IFN-γ) granulocyte and monocyte colony stimulating factor (GM-CSF) were measured in a total of 92 patients with MDD that did not respond to at least one previous antidepressant treatment. Patients were retrospectively divided in two groups: Faster (≤4 weeks) and slower (>4 weeks) onset of the depressive episode defined as the time passing from the first depressive symptoms to a full-blown depressive episode by using information from a clinical interview.

RESULTS

We found significantly lower serum levels of IL-2, IL-4, IL-6, IL-10, TNF-α and IFN-γ in patients with a faster onset compared to patients with a slower onset of the depressive episodes. Furthermore, lower cytokine serum levels of IL-2, IL-8, IL-10 and IFN-γ were found in patients with a shorter duration (less than 6 months) compared to a longer duration (6-24 months) of the current depressive episode. This effect on cytokines was independent from the effect of the speed of onset of the depressive episode.

CONCLUSIONS

Patients with faster onset of the depressive episode might represent a biological subtype of MDD with lower serum levels of IL-2, IL-4, IL-6, IL-10, TNF-α and IFN-γ.

Integrating the monoamine and cytokine hypotheses of depression: Is histamine the missing link?

Psychiatric diseases, like depression, largely affect the central nervous system (CNS). While the underlying neuropathology of depressive illness remains to be elucidated, several hypotheses have been proposed as molecular underpinnings for major depressive disorder, including the monoamine hypothesis and the cytokine hypothesis. The monoamine hypothesis has been largely supported by the pharmaceuticals that target monoamine neurotransmitters as a treatment for depression. However, these antidepressants have come under scrutiny due to their limited clinical efficacy, side effects, and delayed onset of action. The more recent, cytokine hypothesis of depression is supported by the ability of immune-active agents to induce "sickness behaviour" akin to that seen with depression. However, treatments that more selectively target inflammation have yielded inconsistent antidepressive results. As such, neither of these hypotheses can fully explain depressive illness pathology, implying that the underlying neuropathological mechanisms may encompass aspects of both theories. The goal of the current review is to integrate these two well-studied hypotheses and to propose a role for histamine as a potential unifying factor that links monoamines to cytokines. Additionally, we will focus on stress-induced depression, to provide an updated perspective of depressive illness research and thereby identify new potential targets for the treatment of major depressive disorder.

Plasma Indoleamine-2,3-Dioxygenase (IDO) is Increased in Drug-Naï ve Major Depressed Patients and Treatment with Sertraline and Ketoprofen Normalizes IDO in Association with Pro-Inflammatory and Immune- Regulatory Cytokines

BACKGROUND

Major Depression Disorder (MDD) is accompanied by an immune response characterized by increased levels of inflammatory and immune-regulatory cytokines and stimulation of indoleamine-2,3-dioxygenase (IDO). There is also evidence that anti-inflammatory drugs may have clinical efficacy in MDD.

METHODS

This study examined a) IDO in association with interferon (IFN)-γ, Interleukin (IL)-4 and Transforming Growth Factor (TGF)-β1 in 140 drug-naïve MDD patients and 40 normal controls; and b) the effects of an eight-week treatment of sertraline with or without ketoprofen (a nonsteroidal antiinflammatory drug) on the same biomarkers in 44 MDD patients.

RESULTS

Baseline IDO, IFN-γ, TGF-β1 and IL-4 were significantly higher in MDD patients as compared with controls. Treatment with sertraline with or without ketoprofen significantly reduced the baseline levels of all biomarkers to levels which were in the normal range (IDO, TGF-β1, and IL-4) or still somewhat higher than in controls (IFN-γ). Ketoprofen add-on had a significantly greater effect on IDO as compared with placebo. The reductions in IDO, IL-4, and TGF-β1 during treatment were significantly associated with those in the BDI-II.

CONCLUSION

MDD is accompanied by activated immune-inflammatory pathways (including IDO) and the Compensatory Immune-Regulatory System (CIRS). The clinical efficacy of antidepressant treatment may be ascribed at least in part to decrements in IDO and the immune-inflammatory response. These treatments also significantly reduce the more beneficial properties of T helper-2 and T regulatory (Treg) subsets. Future research should develop immune treatments that target the immune-inflammatory response in MDD while enhancing the CIRS.

Major Depression: One Brain, One Disease, One Set of Intertwined Processes

Major depressive disorder (MDD) is a heterogeneous disease affecting one out of five individuals and is the leading cause of disability worldwide. Presently, MDD is considered a multifactorial disease with various causes such as genetic susceptibility, stress, and other pathological processes. Multiple studies allowed the formulation of several theories attempting to describe the development of MDD. However, none of these hypotheses are comprehensive because none of them can explain all cases, mechanisms, and symptoms of MDD. Nevertheless, all of these theories share some common pathways, which lead us to believe that these hypotheses depict several pieces of the same big puzzle. Therefore, in this review, we provide a brief description of these theories and their strengths and weaknesses in an attempt to highlight the common mechanisms and relationships of all major theories of depression and combine them together to present the current overall picture. The analysis of all hypotheses suggests that there is interdependence between all the brain structures and various substances involved in the pathogenesis of MDD, which could be not entirely universal, but can affect all of the brain regions, to one degree or another, depending on the triggering factor, which, in turn, could explain the different subtypes of MDD.

Current directions in biomarkers and endophenotypes for anorexia nervosa: A scoping review

There are currently no validated biomarkers for anorexia nervosa (AN), though recent literature suggests an increased research interest in this area. Biomarkers are objective, measurable indicators of illness that can be used to assist with diagnosis, risk assessment, and tracking of illness state. Related to biomarkers are endophenotypes, which are quantifiable phenomena that are distinct from symptoms and which link genes to manifest illness. In this scoping review, we sought to provide a summary of recent research conducted in the pursuit of biomarkers and endophenotypes for AN. The findings indicate that a number of possible biomarkers which can assess the presence or severity of AN independently of weight status, including psychophysical (e.g., eye-tracking) and biological (e.g., immune, endocrine, metabolomic, neurobiological) markers, are currently under investigation. However, this research is still in early phases and lacking in replication studies. Endophenotype research has largely been confined to the study of several neurocognitive features, with mixed evidence to support their classification as possible endophenotypes for the disorder. The study of biomarkers and endophenotypes in AN involves significant challenges due to confounding factors of illness-related sequalae, such as starvation. Future research in these areas must prioritise direct evaluation of the sensitivity, specificity and test-retest reliability of proposed biomarkers and enhanced control of confounding physical consequences of AN in the study of biomarkers and endophenotypes.

Cytokines and Water Distribution in Anorexia Nervosa

In patients with anorexia nervosa (AN), decreased intracellular (ICW), extracellular (ECW), and total body water (TBW) as well as changes in serum cytokine concentrations have been reported. In this exploratory study, we measured body composition and serum cytokine levels in patients with AN (n = 27) and healthy controls (HCs; n = 13). Eating disorder symptom severity was assessed using the Eating Disorder Examination-Questionnaire (EDE-Q). Body composition was determined by bioimpedance analysis (BIA) which provided information on ICW, ECW, and TBW. Following blood collection, 27 cytokines and chemokines were quantified using multiplex ELISA-based technology: Eotaxin, Eotaxin-3, granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon- (IFN-) γ, interleukin- (IL-) 1α, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12/IL-23p40, IL-12p70, IL-13, IL-15, IL-16, IL-17A, interferon γ-induced protein- (IP-) 10, macrophage inflammatory protein- (MIP-) 1α, MIP-1β, monocyte chemoattractant protein- (MCP-) 1, MCP-4, thymus and activation-regulated chemokine (TARC), TNF-α, and TNF-β. ICW, ECW, and TBW volumes were significantly lower in patients with AN than in HCs. In the whole sample, GM-CSF, MCP-4, and IL-4 were positively, whereas IFN-γ, IL-6, and IL-10 were negatively associated with all three parameters of body water. In AN participants, we found a statistically significant negative correlation of IL-10 with ICW, ECW, and TBW. Our results suggest an interaction between body water and the cytokine system. Underlying mechanisms are unclear but may involve a loss of water from the gut, kidneys, or skin due to AN-associated inflammatory processes.

On inflammatory hypothesis of depression: what is the role of IL-6 in the middle of the chaos?

Many patients with major depressive disorder (MDD) are reported to have higher levels of multiple inflammatory cytokines including interleukin 6 (IL-6). Recent studies both pre-clinical and clinical have advocated for the functional role of IL-6 in development of MDD and suggested a great potential for targeting this cytokine to open new avenues in pharmacotherapy of depression. The purpose of the present narrative review was to provide an integrated account of how IL-6 may contribute to development of depression. All peer-reviewed journal articles published before July 2020 for each area discussed were searched by WOS, PubMed, MEDLINE, Scopus, Google Scholar, for original research, review articles, and book chapters. Publications between 1980 and July 2020 were included. Alterations in IL-6 levels, both within the periphery and the brain, most probably contribute to depression symptomatology in numerous ways. As IL-6 acts on multiple differing target tissues throughout the body, dysregulation of this particular cytokine can precipitate a multitude of events relevant to depression and blocking its effects can prevent further escalation of inflammatory responses, and potentially pave the way for opening new avenues in diagnosis, treatment, and prevention of this debilitating disorder.

Dysregulation of the gut-brain-skin axis and key overlapping inflammatory and immune mechanisms of psoriasis and depression

The occurrence, progression and recurrence of psoriasis are thought to be related to mood and psychological disorders such as depression. Psoriasis can lead to depression, and depression, in turn, exacerbates psoriasis. No specific mechanism can explain the association between psoriasis and depression. The gut-brain-skin axis has been used to explain correlations among the gut microbiota, emotional states and systemic and skin inflammation, and this axis may be associated with overlapping mechanisms between psoriasis and depression. Therefore, in the context of the gut-brain-skin axis, we systematically summarized and comparatively analysed the inflammatory and immune mechanisms of psoriasis and depression and illustrated the dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis and the gut microbiota. This review provides a theoretical basis and new targets for the treatment of psoriasis and depression.

Pathophysiological implications of neuroinflammation mediated HPA axis dysregulation in the prognosis of cancer and depression

Cancer patients are more likely to develop depressive symptoms and show a poor prognosis compared to the normal healthy individuals. Cancer occurrence and the anticancer treatments result in the pro-inflammatory cytokines-mediated inflammation, which dysregulates the HPA-axis activity that may result in depression-like behaviour. Conversely, depression causes the activation of the HPA-axis that results in the downstream release of endogenous glucocorticoids which may result in depressive signs and symptoms in some cancer patients. Depression may also result in non-adherence to treatment and increased mortality in cancer patients. In this review, we have focused on the role of neuroimmune axis and hyperactive HPA-axis in case of both cancer and depression. Therefore, therapeutics targeting the HPA-axis dysregulation could be effective in ameliorating symptoms of depression in cancer patients.

Immunological Disturbances and Neuroimaging Findings in Major Depressive Disorder (MDD) and Alcohol Use Disorder (AUD) Comorbid Patients

Mood disorders and Major Depressive Disorder, in particular, appear to be some of the most common psychiatric disorders with a high rate of comorbidity most frequently of anxiety or substance abuse disorders (alcohol use disorder). In both cases - MDD and AUD, a number of immunological disturbances are observed, such as chronic mild inflammation response, increased level of cytokines, hypercortisolaemia, which lead to specific changes in brain neurotransmitter functions. Some of the contemporary brain imaging techniques are functional magnetic resonance imaging (fMRI) and magnetic spectroscopy which are most commonly used to assess the brain metabolism and functional connectivity changes such as altered responses to emotional stimuli in MDD or overactivation of ventromedial prefrontal areas during delayed and underactivation of dorsolateral prefrontal regions during impulsive reward decisions in AUD and dysfunction of gamma-aminobutyric acid (GABA) and/or glutamate neurotransmitter systems, low NAA and myo-Inositol in both MDD and AUD.

Risk factors for postpartum depression in Chinese women: A cross-sectional study at 6 weeks postpartum

OBJECTIVE

Postpartum depression (PPD) has received increasing attention due to its harmful impacts and high incidence. PPD is affected by physiological and psychological factors, but the conclusions are not uniform at present, so this study explored the risk factors of postpartum depressive symptoms (PPDS) in Chinese population.

METHODS

A total of 397 women attending the obstetric department of the First Affiliated Hospital of Wenzhou Medical University participated in the questionnaire survey, mainly through a cross sectional study. At 6 weeks postpartum, the Edinburgh Postpartum Depression Scale (EPDS) and Pittsburgh Sleep Quality Index (PSQI) were used to assess PPDS and sleep quality, respectively.

RESULTS

The incidence of probable PPDS in our study population was 14.6% at 6 weeks postpartum. Women with blood group A had an almost 3-fold greater risk of PPDS than those with blood group B (OR [95% CI], 2.99 [1.43-6.28], p = 0.004). After adjusting for potential confounding variables, the blood group A phenotype was significantly more prevalent in women with PPDS compared to blood group B (OR [95% CI], 2.65 [1.23-5.70], p = 0.01).

CONCLUSIONS

Compared to women with blood groups B, AB or O, women with blood group A had high odds of PPDS. If this result can be demonstrated and replicated in other populations, blood group A may be a useful predictor of risk for PPDS in Chinese postpartum women.

Association Between Upper-Extremity Health Condition and Depressive Status in an Elderly General Population

Background: This study was designed to investigate whether psychological status is associated with upper-extremity health status in an elderly general population. Methods: Using Quick Disabilities of the Arm, Shoulder, and Hand of the Japanese Society for Surgery of the Hand (QuickDASH-JSSH), we evaluated 200 Japanese elderly people (76 men, 124 women; mean age, 71.6 years, 60-98 years) to assess their upper-extremity-specific health status. Each had completed a self-administered questionnaire including gender and dominant hand items. As an indicator of hand muscle function, we measured their bilateral hand grip. Study participants were assessed for depressive symptoms using the Geriatric Depression Scale Short-Japanese Version (GDS-S-J). Statistical analyses were applied to clarify associations between self-assessed upper-extremity dysfunction and screening results for depressive symptoms in an elderly general population. Results: Those reporting no complaint of an upper extremity were 72 (36 men and 36 women) (36.0%). The GDS-J score was found to have significant positive correlation with age (r = 0.20, P= 0.0045) and the QuickDASH score (r = 0.25, P = 0.0004). The GDS-J score was found to have significant negative correlation with dominant grip (r = −0.15, P = 0.04) and non-dominant grip strength (r = −0.21, P = 0.004). For all participants, multiple regression analysis revealed the QuickDASH score as associated with the GDS-J score. Conclusion: Self-administered upper-extremity health condition as assessed using QuickDASH is correlated with depressive symptoms in elderly people. Objective pathophysiology and subjective illness behavior must be identified in daily clinical practice. A biopsychosocial approach must be used when advising and treating patients.

Hippocampal volume, function, and related molecular activity in anorexia nervosa: A scoping review

INTRODUCTION

Anorexia nervosa (AN) is a serious and persistent eating disorder, characterized by severe dietary restriction and weight loss, with a third of patients developing a  severe-enduring form. The factors contributing to this progression are poorly understood, although there is evidence for impairments in neural structures such as the hippocampus, an area particularly affected by malnutrition and chronic stress.

AREAS COVERED

This study aimed to map the evidence for alterations in hippocampal volume, function, and related molecular activity in anorexia nervosa. PubMed, PsycINFO, and Web of Science were searched for studies related to hippocampal function and integrity using a range of methodologies, such as neuropsychological paradigms, structural and functional magnetic resonance imaging, and analysis of blood components.

EXPERT OPINION

Thirty-nine studies were included in this review. The majority were neuroimaging studies, which found hippocampus-specific volumetric and functional impairments. Neuropsychological studies showed evidence for a specific memory and learning impairments. There was some evidence for molecular abnormalities (e.g. cortisol), although these were few studies. Taken together, our review suggests that the hippocampus might be a particular region of interest when considering neurobiological approaches to understanding AN. These findings warrant further investigation and may lead to novel treatment approaches.

An increase in IL-6 levels at 6-month follow-up visit is associated with SSRI-emergent suicidality in high-risk children and adolescents treated with fluoxetine

Major depressive disorder (MDD) is associated with alterations in circulatory cytokines, in adults as well as in children and adolescents. Administration of selective serotonin reuptake inhibitors (SSRIs) to MDD pediatric patients modifies cytokine levels. However, most studies only assessed changes over a short time period. In this study, we evaluated long-term effects of the SSRI fluoxetine (FLX) in children and adolescents treated for anxiety and/or MDD, including a high-risk group with pre-treatment suicidality. The study group included ninety-two patients (35 boys and 57 girls) with MDD and/or anxiety disorders, aged 13.90 ± 2.41 years. All patients were treated with FLX and followed for 6 months. The study group included children with pretreatment suicidality (high-risk group;N = 62) and without pretreatment suicidality (N = 30) according to the Columbia Suicide Severity Rating Scale. Plasma concentrations of TNFα, IL-6, and IL-1β were measured by enzyme linked immunosorbent assays before and after six months of treatment. IL-6 and IL-1β significantly increased as a factor of time after 6 months of treatment. The elevation was statistically significant confined to children with pretreatment suicidality. Within the children with pretreatment suicidality, IL-6 levels increased significantly after 6 months only in the children who developed SSRI-associated suicidality. To summarize, an increase in IL-6 levels after 6 months of treatment may be associated with SSRI-emergent suicidality in children with pretreatment suicidality. Further studies are needed to clarify the role and mechanism(s) of IL-6 in the pathogenesis of this life-threatening adverse event.

Neurophysiology and Psychopathology Underlying PTSD and Recent Insights into the PTSD Therapies-A Comprehensive Review

Post-traumatic stress disorder (PTSD) is a well-known psychiatric disorder that affects millions of people worldwide. Pharmacodynamic and cognitive-behavioral therapies (CBT) have been used to treat patients with PTSD. However, it remains unclear whether there are concurrent changes in psychopathological and neurophysiological factors associated with PTSD patients. Past reports described those PTSD patients with efficient fatty acid metabolism, neurogenesis, mitochondrial energy balance could improve ability to cope against the conditioned fear responses and traumatic memories. Furthermore, cognitive, behavioral, cellular, and molecular evidence can be combined to create personalized therapies for PTSD sufferers either with or without comorbidities such as depression or memory impairment. Unfortunately, there is still evidence lacking to establish a full understanding of the underlying neurophysiological and psychopathological aspects associated with PTSD. This review has extensively discussed the single nucleotide polymorphism (SNPs) of genetic factors to cause PTSD, the implications of inflammation, neurotransmitter genomics, metabolic alterations, neuroendocrine disturbance (hypothalamus-pituitary-adrenal (HPA) axis), mitochondrial dynamics, neurogenesis, and premature aging related to PTSD-induced psychopathology and neurophysiology. In addition, the review delineated the importance of CBT and several pharmacodynamic therapies to mitigate symptomatology of PTSD.

Antidepressive properties of microglial stimulation in a mouse model of depression induced by chronic unpredictable stress

The decrease of microglia in the hippocampus is a novel mechanism for depression onset. Reversal of this decrease can ameliorate stress-induced depression-like behaviors in rodents. However, the property of this therapeutic strategy remains unclear. We addressed this issue by designing a series of behavioral experiments. Results showed that a single lipopolysaccharide (LPS) injection at the dose of 75 and 100 μg/kg, but not at 30 or 50 μg/kg, produced obvious antidepressant effects in chronic unpredictable stress (CUS) mice at 5 h after the drug administration. In the time-dependent experiment, a single LPS injection (100 μg/kg) ameliorated the CUS-induced depression-like behaviors in mice at 5 and 8 h, but not at 3 h, after the drug administration. The antidepressant effect of a single LPS injection persisted at least 10 days and disappeared at 14 days after the drug administration. 14 days after the first injection, a second LPS injection (100 μg/kg) still produced antidepressant effects in chronically-stressed mice who re-displayed depression-like behaviors at 5 h after the drug administration. The antidepressant effect of LPS appears to be dependent on microglia, as at 5 h after LPS administration (100 μg/kg), the CUS-induced decrease in microglial numbers and Iba-1 mRNA levels in the hippocampus was reversed markedly, and inhibition of microglia by minocycline (40 mg/kg) or PLX33297 (290 mg/kg) prevented the antidepressant effect of LPS in CUS mice. These results indicate that a single LPS injection displays rapid and sustained antidepressant effects in chronically stressed mice likely through stimulating hippocampal microglia.

Protagonist Role of Opioidergic System on Post-Traumatic Stress Disorder and Associated Pain

OBJECTIVE

Post-traumatic stress disorder (PTSD) and chronic pain often co-occur. Studies have shown an interaction between pain and PTSD. In this narrative review, we aim to support conducting comprehensive studies by describing PTSD, pain and determining whether opioidergic system, its agonist and antagonist manipulation could positively or negatively affect PTSD symptoms and concurrent pain.

METHODS

Term searches was done in Google Scholar, Scopus, ScienceDirect, Web of Science and PubMed databases as well as hand searching in key resource journals from 1979-2019.

RESULTS

There are a lot of contradictions and disputes when endogenous opioidergic system and opioidergic antagonist system are studied in PTSD patients. Exogenous morphine administration in PTSD patients can decrease the symptoms of PTSD but it doesn't have a pain reduction effect to an acceptable level. Beta-endorphin as an endogenous opioid is effective in pain reduction in the moment of events but after minutes to hours, the endorphins withdrawal syndrome leads to exaggerated intrusive thoughts and flashbacks of PTSD, which exacerbate the pain. It has also been shown that naloxone, as an opioidergic antagonist, can reduce or increase the PTSD symptoms and its associated pain.

CONCLUSION

Data suggest different roles of opioidergic system and their antagonist in pain control and mood in PTSD. However, further investigations need to be done in order to reveal the role of endogenous opioidergic system and opioidergic antagonist system as a mediator in PTSD patients suffering from acute or chronic pain.

Current challenges and possible future developments in personalized psychiatry with an emphasis on psychotic disorders

A personalized medicine approach seems to be particularly applicable to psychiatry. Indeed, considering mental illness as deregulation, unique to each patient, of molecular pathways, governing the development and functioning of the brain, seems to be the most justified way to understand and treat disorders of this medical category. In order to extract correct information about the implicated molecular pathways, data can be drawn from sampling phenotypic and genetic biomarkers and then analyzed by a machine learning algorithm. This review describes current difficulties in the field of personalized psychiatry and gives several examples of possibly actionable biomarkers of psychotic and other psychiatric disorders, including several examples of genetic studies relevant to personalized psychiatry. Most of these biomarkers are not yet ready to be introduced in clinical practice. In a next step, a perspective on the path personalized psychiatry may take in the future is given, paying particular attention to machine learning algorithms that can be used with the goal of handling multidimensional datasets.

Mood Disorders are Associated With Increased Risk of BPPV: A National Sample Cohort

OBJECTIVES

Few studies have reported that mood disorders increase the risk of benign paroxysmal positional vertigo (BPPV). The purpose of our study was to demonstrate whether the incidence of BPPV in those with mood disorders differs from that in a matched control group.

STUDY DESIGN

Nationwide cohort observational study.

METHODS

Korean Health Insurance Review and Assessment Service-National Patient Samples were collected from 2002 to 2013. A 1:4 matched mood disorder group (n = 59,340) and control group (n = 237,720) were selected. The crude and adjusted (cerebral stroke, ischemic heart disease, anxiety disorder, and osteoporosis histories) hazard ratios (HRs) for depression and BPPV were analyzed using a stratified Cox proportional hazard model. The results were stratified by age, sex, income, region of residence, hypertension, diabetes, and dyslipidemia in these analyses.

RESULTS

The incidence of BPPV was significantly higher in the mood disorder group than in the control group (3.2% vs. 2.1%, P < .001). Mood disorder increased the risk of BPPV (adjusted HR = 1.31, 95% confidence interval [CI] = 1.23-1.39, P < .001). In subgroup analyses, the incidence of BPPV in all age groups and in both sexes was significantly higher in the mood disorder group than in the control group.

CONCLUSION

This population-based cohort study demonstrates that mood disorder was significantly associated with BPPV.

LEVEL OF EVIDENCE

N/A. Laryngoscope, 131:380-385, 2021.

Thyroid autoimmunity and risk of post-partum depression: a systematic review and meta-analysis of longitudinal studies

PURPOSE

The aim of this study was to systematically investigate whether, and to what extent, the detection of thyroid autoimmunity during pregnancy and in the weeks after childbirth is associated with an increased risk of developing post-partum depression (PPD), a condition associated with possible adverse outcomes for both mother and offspring. We performed a systematic review and meta-analysis of longitudinal studies, assessing the incidence of PPD in women with and without anti-thyroperoxidase antibody (TPOAb) positivity.

METHODS

We searched MEDLINE, EMBASE, Web of Science, Cochrane Library, and CINAHL. Methodological quality of the studies was assessed by the Newcastle-Ottawa Scale. In the presence of even modest between-studies heterogeneity, assessed by Cochrane Q and I² tests, risk ratios (RRs) for PPD were combined using a random effects model. Funnel plot and trim-and-fill analysis were used to assess publication bias.

RESULTS

Five included studies provided information on 449 women with TPOAb-positive and 2483 TPOAb-negative women. Pooled RR indicated a significantly increased risk to develop PPD in TPOAb-positive group (RR 1.49, 95% CI 1.11-2.00; P = 0.008; I² = 47%, P_{for heterogeneity} = 0.11). Consistent with a possible publication bias, the trim-and-fill test detected two putative missing studies in the funnel plot. Nevertheless, the adjustment for publication bias produced a negligible effect on the pooled estimate (adjusted RR 1.41, 95% CI 1.18-1.68, P = 0.0002).

CONCLUSIONS

Thyroid autoimmunity during pregnancy and in the weeks after childbirth is associated with an increased risk of developing PPD. Further well-designed studies are warranted to confirm this association and elucidate underlying pathophysiological mechanisms.

PROSPERO REGISTRATION

CRD42019129643.

A longitudinal analysis of cytokines in anorexia nervosa

OBJECTIVE

Inflammation has been proposed to have a pathophysiological role in anorexia nervosa (AN) and to contribute to the maintenance of the disorder. Longitudinal cytokine research in AN has focused on only a few pro-inflammatory cytokines. We assessed a broad range of cytokines over time in people undergoing specialised treatment for AN.

METHOD

We measured serum concentrations of 27 cytokines in people with AN (n = 23). Body mass index (BMI), eating disorder (ED) symptoms and general psychopathology were assessed and blood samples were collected within four weeks of the commencement of specialised ED treatment (baseline) and at 12- and 24-week follow-ups.

RESULTS

Both BMI and ED symptoms improved over the assessment period. Linear mixed models showed that log IL-6 decreased between baseline and week 12 assessments. By week 12, log IL-6 values were comparable to levels in healthy individuals. Log IL-7 increased from week 12 to week 24.

DISCUSSION

Initially elevated IL-6 serum concentrations appear to 'normalize' during the first 3-months of specialised treatment for AN and this co-occurs with improvements in ED symptoms. Therefore, IL-6 has the potential to be a state biomarker for AN.

Effect of Toll-like receptor 4 on depressive-like behaviors induced by chronic social defeat stress

INTRODUCTION

A growing body of evidence suggests that stress is an important factor in depression, and pro-inflammatory cytokines contribute to the occurrence and development of depression in both animal models and human patients. Toll-like receptor 4 (TLR4) has been shown to be a key innate immune pattern recognition receptor involved in the regulation of stress responses and inflammation. However, the exact effects of TLR4 on depressive-like behaviors induced by chronic social defeat stress (CSDS) are not known.

METHODS

In this study, the effects of TLR4 on depressive-like behaviors were investigated in an animal model of depression induced by CSDS. The depressive-like behaviors were assessed by forced swimming test (FST), social interaction test (SIT), and light-dark box test (LDT). The protein expressions of TLR4 and tumor necrosis factor-α (TNF-α) in the hippocampus were measured using Western blotting.

RESULTS

We found that CSDS increased TLR4 protein levels in the hippocampus and induced behavioral despair in FST, social avoidance in SIT, and anxiety-like behavior in LDT. Fluoxetine normalized the increased expression of TLR4 and reversed behavioral despair, social avoidance, as well as anxiety-like behavior induced by CSDS. However, directly blocking TLR4, by using either TLR4 inhibitor TAK-242 or knockout of TLR4, only inhibited behavioral despair, but not social avoidance or anxiety-like behavior induced by CSDS.

CONCLUSIONS

These results demonstrate a specific modulating role of TLR4 in behavioral despair induced by CSDS and suggest that TAK-242 may be a beneficial treatment for patients with behavioral despair.

Neural networks and the anti-inflammatory effect of transcutaneous auricular vagus nerve stimulation in depression

Transcutaneous auricular vagus nerve stimulation (taVNS) is a relatively non-invasive alternative treatment for patients suffering from major depressive disorder (MDD). It has been postulated that acupuncture may achieve its treatment effects on MDD through suppression of vagal nerve inflammatory responses. Our previous research established that taVNS significantly increases amygdala–dorsolateral prefrontal cortex connectivity, which is associated with a reduction in depression severity. However, the relationship between taVNS and the central/peripheral functional state of the immune system, as well as changes in brain neural circuits, have not as yet been elucidated. In the present paper, we outline the anatomic foundation of taVNS and emphasize that it significantly modulates the activity and connectivity of a wide range of neural networks, including the default mode network, executive network, and networks involved in emotional and reward circuits. In addition, we present the inflammatory mechanism of MDD and describe how taVNS inhibits central and peripheral inflammation, which is possibly related to the effectiveness of taVNS in reducing depression severity. Our review suggests a link between the suppression of inflammation and changes in brain regions/circuits post taVNS.

Toward a New Model of Understanding, Preventing, and Treating Adolescent Depression Focusing on Exhaustion and Stress

OBJECTIVE

Adolescent depression is a heterogeneous disorder, with a wide variety of symptoms and inconsistent treatment response, and is not completely understood. A dysregulated stress system is a consistent finding, however, and exhaustion is a consistent trait in adolescent patients. The aim of this paper is to critically assess current hypotheses in adolescent depression research and reframe causes and treatment approaches.

METHODS

A mixed-method approach involved a review based on publications from PubMed, Embase and PsycInfo, and two exemplary adolescent cases.

RESULTS

Both cases show a spiral of stress and exhaustion, but with a different profile of symptoms and coping mechanisms. Reframing both cases from the perspective of coping behavior, searching for the sources of experienced stress and exhaustion, showed coping similarities. This proved essential in the successful personalized treatment and recovery process. In combination with recent evidence, both cases support the functional reframing of depression as the outcome of a stress- and exhaustion-related spiralling mechanism.

CONCLUSIONS

We propose to open up a symptom-based, mood-centered view to a model in which adolescent depression is framed as a consecutive failure of stress coping mechanisms and chronic exhaustion. Addressing exhaustion and coping primarily as a treatment strategy in adolescents and young adults might work in synergy with existing treatments and improve overall outcomes. This perspective warrants further investigation.

Ligands and receptors of the TNF superfamily are decreased in major depression and during early antidepressant therapy

BACKGROUND

The up-regulation of pro-inflammatory agents, amongst them tumor necrosis factor (TNF), may represent low-grade inflammation in major depression. To further elucidate inflammatory mechanisms related to TNF in depression, the aim of the current study was to investigate the involvement of ligands and receptors of the TNF/TNF-receptor-superfamily yet un- or little explored in major depression.

METHODS

Serum levels of ligands (TNF, TNF-related weak inducer of apoptosis [TWEAK], B-cell activating factor [BAFF], tumor necrosis factor superfamily member 14 [TNFSF14; LIGHT], A proliferation-inducing ligand [APRIL]) and receptor molecules (TNF receptor superfamily member 8 [TNFRSF8; sCD30], soluble TNF receptor type 1 [sTNFR1] and type 2 [sTNFR2]) of the TNF/TNF-receptor-superfamily were measured in 50 unmedicated patients suffering from major depression and 48 healthy controls and were reassessed in 37 of the depressed patients two weeks after the initiation of antidepressive treatment.

RESULTS

In comparison to the healthy controls, the interrelated serum levels of TWEAK, BAFF, TNFSF8, sTNFR1 and sTNFR2 were reduced both in the unmedicated and medicated depressed patients. Serum levels of BAFF and TNF significantly increased during the initiation of antidepressive treatment. In the combined sample of unmedicated depressed and healthy controls, but not the separate groups, scores of the BDI-II inversely correlated with levels of TWEAK, BAFF, sTNFR1, sTNFR2 and TNFSF8.

CONCLUSION

The current findings give evidence for a role of the TNF/TNF-receptor-superfamily in the pathophysiology of major depression that may involve reduced tissue regeneration and neurogenesis rather than an acceleration of pro-inflammatory pathways.

Modulation of gut microbiota by chlorogenic acid pretreatment on rats with adrenocorticotropic hormone induced depression-like behavior

Gut microbiota dysbiosis has been implicated as a vital element in the development or exacerbation of mental disorders, such as major depressive disorder (MDD). Based on the current interest in the gut-brain axis, we investigate the effects of chlorogenic acid (CGA) on gut microbiota in a rat model of MDD. Depression was induced by the adrenocorticotropic hormone (ACTH, 100 μg per rat) in male Wistar rats, which were intervened with using saline or CGA (500 mg kg-1). Behavioral changes and serum parameters were assessed and fecal samples were analyzed by 16S rRNA gene sequencing. Our studies demonstrated that CGA pretreatment ameliorated depression-like behavior (SPT, FST, TST, and OFT) and serum biochemical levels (5-HT, DA, IL-6, and TNF-α) in ACTH-induced depression rats. In addition, CGA ameliorated the decrease in fecal microbiota diversity in ACTH-treated rats. In particular, at the genus level, the changes in the relative abundance of some key bacteria such as Desulfovibrionales, Desulfovibrio, Klebsiella, Burkholderiales, and Bifidobacterium were modulated by CGA pretreatment. These results indicated that CGA could modify the gut microbial community structure, which may contribute to its antidepressant effects.

A systematic review of in vitro cytokine production in eating disorders

BACKGROUND

Eating disorders (EDs) have been associated with alterations in cytokine concentrations and production. This review examines whether in vitro cytokine production (i) is altered in people with EDs compared to healthy participants; and (ii) changes in response to treatment?

METHODS

Using PRISMA guidelines, we systematically reviewed articles reporting group comparisons or longitudinal assessments of spontaneous and/or stimulated cytokine production in vitro in people with EDs.

RESULTS

Twelve studies were included. Cross-sectional results were mixed in anorexia nervosa. Only one study measured cytokine production in bulimia nervosa. Two longitudinal studies showed that daily yoghurt consumption increases phytohemagglutinin-stimulated interferon-γ production in anorexia nervosa.

CONCLUSION

The mixed results could be accounted for by variations in experimental design. Our findings suggest that cytokine production could possibly be modulated through dietary interventions. However, due to the methodological heterogeneity and shortcomings of the included studies, it seems unreasonable to draw further conclusions.

The cellular and molecular basis of major depressive disorder: towards a unified model for understanding clinical depression

Major depressive disorder (MDD) is considered a serious public health issue that adversely impacts an individual's quality of life and contributes significantly to the global burden of disease. The clinical heterogeneity that exists among patients limits the ability of MDD to be accurately diagnosed and currently, a symptom-based approach is utilized in many cases. Due to the complex nature of this disorder, and lack of precise knowledge regarding the pathophysiology, effective management is challenging. The aetiology and pathophysiology of MDD remain largely unknown given the complex genetic and environmental interactions that are involved. Nonetheless, the aetiology and pathophysiology of MDD have been the subject of extensive research, and there is a vast body of literature that exists. Here we overview the key hypotheses that have been proposed for the neurobiology of MDD and highlight the need for a unified model, as many of these pathways are integrated. Key pathways discussed include neurotransmission, neuroinflammation, clock gene machinery pathways, oxidative stress, role of neurotrophins, stress response pathways, the endocannabinoid and endovanilloid systems, and the endogenous opioid system. We also describe the current management of MDD, and emerging novel therapies, with particular focus on patients with treatment-resistant depression (TRD).

Serum Levels of Tumor Necrosis Factor-α and Loudness Dependence of Auditory Evoked Potentials at Pretreatment and Posttreatment in Patients with Major Depressive Disorder

Background: Proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α), are associated with the pathophysiology of major depressive disorder (MDD). Several studies have reported that increased TNF-α might be associated with tryptophan depletion, which eventually could result in MDD. However, other studies revealed that TNF-α increased serotonin firing in raphe. Therefore, whether TNF-α increases or decreases serotonin activity remains unclear. Here, we aimed to determine the relationship between serum TNF-α level and central serotonergic activity using the loudness dependence of auditory evoked potentials (LDAEP) and standardized low-resolution brain electromagnetic tomography (sLORETA), as well as to evaluate the effects of antidepressants on TNF-α levels. Methods: LDAEP, serum TNF-α level, and depression severity were measured in 64 MDD outpatients pre and post 3 months of treatment. Results: Pretreatment TNF-α levels were negatively correlated with the pretreatment N1 sLORETA-LDAEP, P2 sLORETA-LDAEP, and N1/P2 sLORETA-LDAEP (p < 0.05). In multiple regression analysis for N1/P2 sLORETA-LDAEP, lower N1/P2 sLORETA-LDAEP was significantly related to higher TNF-α (CE = −0.047, p = 0.017) when all subjects were dichotomized based on the median TNF-α level (7.16 pg/mL) into pretreatment low- and high-TNF-α groups. In addition, the pretreatment Beck Depression Inventory, P2 LDAEP, and N1/P2 sLORETA-LDAEP were greater in the high-TNF-α groups than in the low-TNF-α groups (p < 0.05). Moreover, the posttreatment TNF-α level was significantly decreased compared to the pretreatment TNF-α level (z = −2.581, p = 0.01). However, the posttreatment TNF-α levels were not associated with posttreatment LDAEP. Conclusions: Higher TNF-α level is associated with decreased LDAEP, which could indicate compensatory elevation of central serotonin activity in outpatients with MDD, although this effect disappeared and TNF-α level was reduced after three months of antidepressant treatment.