Effect of celecoxib add-on treatment on symptoms and serum IL-6 concentrations in patients with major depressive disorder: randomized double-blind placebo-controlled study

Drug repurposing may generate novel approaches to treating depression

Objectives

The breakthrough advancements in scientific medical research have greatly improved our understanding of the pathogenesis of depression, encouraging drug discoverers to take a shorter path than ever through drug repurposing to generate new antidepressant medications. In addition to reduced noradrenergic and serotonergic neurotransmission in the brain, other coincidence features such as glutamate neurotoxicity, inflammation and/or cerebrovascular insufficiency are implicated in the pathogenesis of major depressive disorder and late-life depression. This short review discusses the progress made in repurposing drugs for antidepressant actions.

Key findings

Drugs being repurposed as antidepressants act on novel drug targets, thereby treating resistant depression and improving remission rate. Drugs such as ketamine, dextromethorphan/quinidine and scopolamine are rapidly acting antidepressants targeting glutamate receptors. Nimodipine and quetiapine are efficient add-on therapy for late-life depression. Anti-inflammatory drugs, statins, insulin sensitizers, minocycline could remarkably contribute to treating refractory depression.

Summary

Drug repurposing represents an alternative approach to cope with major obstacles, including financial insufficiency and unavoidable long lag evaluation time, undermining the classical pathway of developing new hit compounds into clinically approved antidepressants.

Immunological aspects of the treatment of depression and schizophrenia

Schizophrenia and major depression (MD) have been associated with immune system dysfunction. One example of this is the altered level of cytokines—important inflammatory mediators—in blood, and a proinflammatory immune state has been described in some subgroups of patients. A knock to the immune system in early life might trigger a life-long increased immune reactivity, and infections and autoimmune disorders are now known to be risk factors for development of schizophrenia and MD. Pro- and anti-inflammatory cytokines mediate indoleamine 2,3-dioxygenase activity; this enzyme drives metabolism of tryptophan and kynurenin in the central nervous system and degrades serotonin. Alterations of serotonergic, noradrenergic, and glutamatergic neurotransmission have been associated with low-level neuroinflammation, and anti-inflammatory compounds have a therapeutic benefit in MD and schizophrenia, as shown in meta-analyses. Moreover, antidepressants and antipsychotics have intrinsic immunomodulatory effects. With evidence pointing to the role inflammatory processes play in the pathogenesis of major psychiatric disorders, this review will look at various immunological aspects of treatment of such disorders.

Efficacy and safety of celecoxib monotherapy for mild to moderate depression in patients with colorectal cancer: A randomized double-blind, placebo controlled trial

Cancer-related inflammation is an essential process in malignancies. Celecoxib, a nonsteroidal anti-inflammatory drug that acts via the selective inhibition of cyclooxygenase (COX)-2, has shown favorable effects in several psychiatric disorders. The present study aimed to assess the safety and efficacy of celecoxib single therapy on depressive symptoms of patients with colorectal cancer who underwent chemotherapy. The study was conducted as a 6-week, parallel-group, randomized, double-blind, placebo-controlled trial. Forty participants randomly received either 400mg/day celecoxib or placebo. Treatment effect was assessed using the Hamilton Depression Rating Scale (HDRS) and Visual Analogue Scale (VAS) score at baseline and at week 2, 4 and 6 of the trial. Over 6 weeks, patients who received celecoxib showed significant improvement in scores of the Hamilton Depression rating Scale (P=0.003). When comparing the Mean Difference (95% CI) between the two groups of therapy, the celecoxib group demonstrated greater reduction in HDRS score during the study period at weeks 4 (1.95, 95% CI 0.27-3.63, P value =0.024) and 6 (2.60, 95% CI 0.96-4.23, P=0.003). This study indicates celecoxib as a potential monotherapy treatment strategy for mild to moderate depression in patients with colorectal cancer who underwent chemotherapy.

Effect of Early and Prophylactic Nonsteroidal Anti-Inflammatory Drugs on Flare Duration in Pediatric Acute-Onset Neuropsychiatric Syndrome: An Observational Study of Patients Followed by an Academic Community-Based Pediatric Acute-Onset Neuropsychiatric Syndrome Clinic

INTRODUCTION

Pediatric Acute-onset Neuropsychiatric Syndrome (PANS) is characterized by the sudden onset of severe obsessive-compulsive symptoms and/or eating restriction along with at least two coinciding neuropsychiatric symptoms. When associated with group A Streptococcus, the syndrome is labeled Pediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcal infections (PANDAS). An abnormal immune response to infection and subsequent neuroinflammation is postulated to play an etiologic role. We evaluated the impact of nonsteroidal anti-inflammatory drug (NSAID) treatment on flare duration in PANS/PANDAS.

METHODS

Patient inclusion criteria: Patients were included if they had at least one neuropsychiatric deterioration ("flare") that met strict PANS/PANDAS research criteria and for which flare duration could be assessed. Flare inclusion criteria: Any flare that started before October 15, 2016 was included and followed until the flare resolved or until the end of our data collection (November 1, 2016). Flare exclusion criteria: Flares were excluded if they were incompletely resolved, treated with aggressive immunomodulation, or treated with NSAIDs late (>30 days of flare onset). Ninety-five patients met study inclusion criteria and collectively experienced 390 flares that met flare criteria. Data were analyzed using multilevel linear models, adjusting for demographics, disease, and treatment covariates.

RESULTS

NSAID use was associated with a significantly shorter flare duration. Flares not treated with NSAIDs had a mean duration of approximately 12.2 weeks (95% CI: 9.3-15.1). Flares that occurred while the child was on NSAID maintenance therapy were approximately 4 weeks shorter than flares not managed with NSAIDs (95% CI: 1.85-6.24; p < 0.0001). Flares treated with NSAIDs within 30 days of flare onset were approximately 2.6 weeks shorter than flares not managed with NSAIDs (95% CI: 0.43-4.68; p = 0.02). Flares treated prophylactically and those treated early with NSAIDs did not differ in duration (p = 0.26). Among the flares that received NSAID treatment within the first 30 days, earlier intervention was modestly associated with shorter flare durations (i.e., for each day that NSAID treatment was delayed, flare duration increased by 0.18 weeks; 95% CI: 0.03-0.33; p = 0.02), though it was not statistically significant after controlling for covariates (p = 0.06).

CONCLUSION

NSAIDs given prophylactically or within 30 days of flare onset may shorten neuropsychiatric symptom duration in patients with new-onset and relapsing/remitting PANS and PANDAS. A randomized placebo-control clinical trial of NSAIDs in PANS is warranted to formally assess treatment efficacy.

Clinical Management of Pediatric Acute-Onset Neuropsychiatric Syndrome: Part II-Use of Immunomodulatory Therapies

Introduction: Pediatric Acute-onset Neuropsychiatric Syndrome (PANS) is a clinically heterogeneous disorder with a number of different etiologies and disease mechanisms. Inflammatory and postinfectious autoimmune presentations of PANS occur frequently, with some clinical series documenting immune abnormalities in 75%-80% of patients. Thus, comprehensive treatment protocols must include immunological interventions, but their use should be reserved only for PANS cases in which the symptoms represent underlying neuroinflammation or postinfectious autoimmunity, as seen in the PANDAS subgroup (Pediatric Autoimmune Neuropsychiatric Disorders associated with Streptococcal infections). Methods: The PANS Research Consortium (PRC) immunomodulatory task force is comprised of immunologists, rheumatologists, neurologists, infectious disease experts, general pediatricians, psychiatrists, nurse practitioners, and basic scientists with expertise in neuroimmunology and PANS-related animal models. Preliminary treatment guidelines were created in the Spring of 2014 at the National Institute of Health and refined over the ensuing 2 years over conference calls and a shared web-based document. Seven pediatric mental health practitioners, with expertise in diagnosing and monitoring patients with PANS, were consulted to create categories in disease severity and critically review final recommendations. All authors played a role in creating these guidelines. The views of all authors were incorporated and all authors gave final approval of these guidelines. Results: Separate guidelines were created for the use of immunomodulatory therapies in PANS patients with (1) mild, (2) moderate-to-severe, and (3) extreme/life-threatening severity. For mildly impairing PANS, the most appropriate therapy may be "tincture of time" combined with cognitive behavioral therapy and other supportive therapies. If symptoms persist, nonsteroidal anti-inflammatory drugs and/or short oral corticosteroid bursts are recommended. For moderate-to-severe PANS, oral or intravenous corticosteroids may be sufficient. However, intravenous immunoglobulin (IVIG) is often the preferred treatment for these patients by most PRC members. For more severe or chronic presentations, prolonged corticosteroid courses (with taper) or repeated high-dose corticosteroids may be indicated. For PANS with extreme and life-threatening impairment, therapeutic plasma exchange is the first-line therapy given either alone or in combination with IVIG, high-dose intravenous corticosteroids, and/or rituximab. Conclusions: These recommendations will help guide the use of anti-inflammatory and immunomodulatory therapy in the treatment of PANS.

Anti-inflammatory treatment for major depressive disorder: implications for patients with an elevated immune profile and non-responders to standard antidepressant therapy

Major depressive disorder (MDD) is a prevalent and disabling psychiatric disease with rates of non-responsiveness to antidepressants ranging from 30-50%. Historically, the monoamine depletion hypothesis has dominated the view on the pathophysiology of depression. However, the lack of responsiveness to antidepressants and treatment resistance suggests that additional mechanisms might play a role. Evidence has shown that a subgroup of depressive patients may have an underlying immune deregulation that could explain the lack of therapeutic benefit from antidepressants. Stimuli like inflammation and infection can trigger the activation of microglia to release pro-inflammatory cytokines, acting on two main pathways: (1) activation of the hypothalamic-pituitary adrenal axis, generating an imbalance in the serotonergic and noradrenergic circuits; (2) increased activity of the enzyme indoleamine-2,3-dioxygenase, resulting in depletion of serotonin levels and the production of quinolinic acid. If this hypothesis is proven true, the subgroup of MDD patients with increased levels of pro-inflammatory cytokines, mainly IL-6, TNF-α and IL-1β, might benefit from an anti-inflammatory intervention. Here, we discuss the pre-clinical and clinical studies that have provided support for treatment with non-steroidal anti-inflammatory drugs in depressed patients with inflammatory comorbidities or an elevated immune profile, as well as evidences for anti-inflammatory properties of standard antidepressants.

Anti-inflammatory treatment and risk for depression after first-time stroke in a cohort of 147 487 Danish patients

BACKGROUND

Depression is a common complication after stroke, and inflammation may be a pathophysiological mechanism. This study examines whether anti-inflammatory treatment with acetylsalicylic acid (ASA), nonsteroid anti-inflammatory drugs (NSAIDs) or statins influence the risk of depression after stroke.

METHODS

A register-based cohort including all patients admitted to hospital with a first-time stroke from Jan. 1, 2001, through Dec. 31, 2011, and a nonstroke population with a similar age and sex distribution was followed for depression until Dec. 31, 2014. Depression was defined as having a hospital contact with depression or having filled prescriptions for antidepressant medication. The associations between redeemed prescriptions of ASA, NSAIDs or statins with early- (≤ 1 year after stroke or study entry) and late-onset (> 1 year after stroke or study entry) depression were analyzed using Cox proportional hazard regression.

RESULTS

We identified 147 487 patients with first-time stroke and 160 235 individuals without stroke for inclusion in our study. Redeemed prescriptions of ASA, NSAIDs or statins after stroke decreased the risk for early-onset depression, especially in patients with ischemic or severe stroke. Patients who received a combination of anti-inflammatory treatments had the lowest risk for early-onset depression. On the other hand, use of ASA or NSAIDs 1 year after stroke increased the risk for late-onset depression, whereas statin use was associated with a tendency toward a decreased risk.

LIMITATIONS

The study used prescription of antidepressant medication as a proxy measure for depression and did not include anti-inflammatory drugs bought over the counter.

CONCLUSION

Anti-inflammatory treatment is associated with a lower risk for depression shortly after stroke but a higher risk for late depression. This suggests that inflammation contributes differently to the development of depression after stroke depending on the time of onset.

Course of Neuropsychiatric Symptoms After Introduction and Removal of Nonsteroidal Anti-Inflammatory Drugs: A Pediatric Observational Study

OBJECTIVE

Accumulating evidence suggests that anti-inflammatory interventions can modulate neuropsychiatric symptoms. Pediatric Acute-onset Neuropsychiatric Syndrome (PANS) is characterized by an abrupt and dramatic onset of obsessive-compulsive (OC) symptoms and/or severely restrictive food intake and at least two coinciding, equally debilitating neuropsychiatric symptoms. When associated with group A Streptococcus, the syndrome is labeled Pediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcal infections (PANDAS). Here, we describe the course of neuropsychiatric symptoms in patients diagnosed with PANS and PANDAS after introduction or removal of nonsteroidal anti-inflammatory drugs (NSAIDs).

STUDY DESIGN

We reviewed the electronic medical records (EMR) of 218 consecutive patients evaluated in our Stanford PANS Clinic for patients who met strict PANS or PANDAS research criteria and received NSAIDs for arthritis, pain, and/or psychiatric symptoms. We describe neuropsychiatric symptoms that were noted in the EMR before, during, and after NSAIDs were introduced or removed as the sole change in pharmacologic treatment.

RESULTS

Seventy-seven patients were included in the current study. Of the 52 trials in which NSAID addition was the sole change in treatment, 16 (31%) coincided with an improvement in patients' neuropsychiatric symptoms. Of the 57 trials in which removal of NSAID treatment was the sole change in treatment, 20 (35%) coincided with escalation in patients' neuropsychiatric symptoms. Thirty patients (39%) experienced side effects, mainly mild gastrointestinal symptoms, which self-resolved after removal of NSAID, reduction of dose, or change in NSAID.

CONCLUSIONS

Improvement in neuropsychiatric symptoms was evident in roughly one-third of NSAID treatment trials. A randomized clinical trial will be necessary to confirm whether NSAIDs are successful in reducing neuropsychiatric symptoms in youth with PANS.

Anti-inflammatory treatments for mood disorders: Systematic review and meta-analysis

BACKGROUND

Recent studies suggest that anti-inflammatory medication may play a role in the treatment of mood disorders.

AIMS

The purpose of this study was to determine the efficacy of anti-inflammatory drugs in patients with major depressive disorder and bipolar disorder.

METHOD

The Cochrane Central Register of Controlled Trials, PubMed, EMBASE, PsychINFO and Clinicaltrials.gov were searched from inception until 15 April 2017 for completed and on-going randomized controlled trials of anti-inflammatory agents for major depressive disorder and bipolar disorder. Data from randomized controlled trials assessing the antidepressant and anti-manic effect of adjunctive mechanistically diverse anti-inflammatory agents were pooled to determine standard mean differences (SMDs) compared with placebo and/or treatment as usual.

RESULTS

Patients receiving anti-inflammatory agents showed lower post-treatment depressive symptom scores compared with those receiving placebo with a standard mean difference of -0.71 (six randomized controlled trials, n=214, 95% CI -1.24 to -0.17, p=0.009). Anti-inflammatory treatment was found to reduce post-treatment manic symptom scores with a standard mean difference of -0.72 (three randomized controlled trials, n=96, 95% CI -1.31 to -0.13, p=0.02). Anti-inflammatories did not show a statistically significant improvement in the secondary outcome measure (change in symptom scores from baseline to outcome).

CONCLUSIONS

Further high quality trials are needed before making recommendations for the routine clinical use of anti-inflammatories in the treatment of mood disorders.

Depressive subtypes in an elderly cohort identified using latent class analysis

BACKGROUND

Clinical findings indicate heterogeneity of depressive disorders, stressing the importance of subtyping depression for research and clinical care. Subtypes of the common late life depression are however seldom studied. Data-driven methods may help provide a more empirically-based classification of late-life depression.

METHODS

Data were used from the Netherlands Study of Depression in Older People (NESDO) derived from 359 persons, aged 60 years or older, with a current diagnosis of major depressive disorder. Latent class analysis (LCA) was used to identify subtypes of depression, using ten CIDI-based depression items. Classes were then characterized using various sociodemographic and clinical characteristics.

RESULTS

The most prevalent class, as identified by LCA, was a moderate-severe class (prevalence 46.5%), followed by a severe melancholic class (prevalence 38.4%), and a severe atypical class (prevalence 15.0%). The strongest distinguishing features between the three classes were appetite and weight and, to a lesser extent, psychomotor symptoms and loss of interest. Compared with the melancholic class, the severe atypical class had the highest prevalence of females, the lowest mean age, the highest BMI, and highest prevalence of both cardiovascular disease, and metabolic syndrome.

LIMITATIONS

The strongest distinguishing symptoms, appetite and weight, could be correlated. Further, only longitudinal studies could demonstrate whether the identified classes are stable on the long term.

DISCUSSION

In older persons with depressive disorders, three distinct subtypes were identified, similar to subtypes found in younger adults. The strongest distinguishing features were appetite and weight; moreover, classes differed strongly on prevalence of metabolic syndrome and cardiovascular disease. These findings suggest differences in the involvement of metabolic pathways across classes, which should be considered when investigating the pathogenesis and (eventually) treatment of depression in older persons.

Altered serum levels of TNF-α, IL-6, and IL-18 in depressive disorder patients

OBJECTIVE

Depressive disorder is associated with abnormal changes in cytokines levels. This study aimed to assess serum concentrations of tumor necrosis factor (TNF) α, interleukin (IL) 6, and IL-18 in depressive patients. The correlations between these three cytokine concentrations and the patients' clinical characteristics were also assessed.

METHODS

Serum TNF-α, IL-6, and IL-18 concentrations were assessed using enzyme-linked immunosorbent assay from 64 depressive patients and 80 healthy control subjects. Depressive symptoms of patients were assessed using Hamilton Depression Scale-17.

RESULTS

Depressive patients had increased serum TNF-α and IL-6 concentrations but decreased IL-18 concentrations than controls. TNF-α and IL-6 concentrations were significantly positively associated with Hamilton Depression Scale-17 scores in depressive patients.

CONCLUSION

These findings provided additional evidence that altered TNF-α, IL-6, and IL-18 activities may contribute to the pathophysiology of depressive disorder.

Evidence for Inflammation-Associated Depression

This chapter explores the evidence supporting inflammation-associated depression. Data to date suggest a bidirectional relationship between inflammation and depression wherein one process can drive the other. A wealth of animal and clinical studies have demonstrated an association between concentrations of pro-inflammatory cytokines - specifically interleukin (IL)-1β, IL-6, and tumor necrosis factor-α - and depressive symptoms. There is also evidence that this pro-inflammatory state is accompanied by aberrant inflammation-related processes including platelet activation factor hyperactivity, oxidative and nitrosative stress, and damage to mitochondria. These complex and interrelated mechanisms can collectively contribute to negative neurobiological outcomes that may, in part, underlie the etiopathology of depression. Mounting evidence has shown a concomitant reduction in both depressive symptoms and pro-inflammatory cytokine concentrations following treatment with pharmacological anti-inflammatory interventions. Taken together, the reviewed preclinical and clinical findings may suggest the existence of a distinct inflammatory subtype of depression in which these patients exhibit unique biochemical and clinical features and may potentially experience improved clinical outcomes with inflammation-targeted pharmacotherapy.

Do Statins Have Antidepressant Effects?

Statins are used widely in primary and secondary prevention of cardiovascular disease; a treatment effect that has long been thought to be due to their cholesterol-lowering properties. However, statins also have a wide range of anti-inflammatory effects independent of their lipid-lowering mechanisms. In depression, low-grade inflammation is a replicated finding, and several studies have shown antidepressant properties of diverse anti-inflammatory drugs. Large observational studies have suggested reduced risks of depression amongst those taking statins, an effect that is thought to be explained by the anti-inflammatory properties of this class of drugs. Also, preliminary randomized controlled trials (RCTs) have indicated that statins may have adjunctive antidepressant effects when used as add-on treatment to selective serotonin reuptake inhibitors (SSRIs). However, the RCTs were small and limited by low generalizability, and some early observational studies have pointed towards potential neuropsychiatric adverse effects of statin treatment. Nevertheless, based on the good tolerability and general safety of the statins, researchers are currently investigating the potential antidepressant properties of these agents. The present review aims to give an overview on the potential antidepressant effects of statins based on their anti-inflammatory properties, covering topics such as safety versus treatment effects, potential mechanisms of action and the possibility of targeted treatment (precision medicine).

Cyclooxygenase-2 Signalling Pathway in the Cortex is Involved in the Pathophysiological Mechanisms in the Rat Model of Depression

This study was designed to investigate the effect of the cortical cyclooxygenase-2 (COX2) pathway on depressive behaviour in rats. Meloxicam, COX2 overexpressed lentivirus and COX2 RNAi lentivirus were administered to Sprague-Dawley rats subjected to chronic unpredictable mild stress (CUMS). Behaviour tests, biochemistry and immunohistochemistry methods, enzyme-linked immunosorbent assays, western blotting and reverse transcription polymerase chain reactions were used to evaluate the changes in rat behaviour and the cortical COX2 pathway. CUMS rats showed depressive–like behaviours. The superoxide dismutase activity and cyclic adenosine monophosphate (cAMP) contents were significantly decreased, the contents of malondialdehyde, prostaglandin E2 (PGE2) and inflammatory cytokines were significantly increased. The expressions of protein kinase A (PKA) and cAMP response element-binding protein (CREB) were decreased, and the levels of brain-derived neurotrophic factor (BDNF) and COX2 were significantly increased. Meloxicam and COX2 RNAi lentivirus significantly alleviated the abnormalities induced by CUMS, while COX2 overexpressed lentivirus aggravated these abnormalities. Our results indicated that the cortical COX2 pathway was activated in CUMS rats. Inhibition of COX2 activity/expression can obviously improve depressive behaviours in CUMS rats. Upregulating COX2 expression can increase the susceptibility of rats to CUMS. An imbalance in the cortical COX2-PGE2-cAMP/PKA-CREB-BDNF signalling pathway participates in the pathogenic mechanism of depression.

Interleukin-4 is a participant in the regulation of depressive-like behavior

Inflammatory immune activation has been frequently associated with the development of major depression. Microglia might serve as an important interface in this immune system-to-brain communication. Interleukin-4, the major Th2 type cytokine, might be protective against depression due to its ability to counter-regulate inflammation and to inhibit serotonin transporter activity. By using an Interferon-α mouse model, we show that a decreased IL-4 responsiveness of microglia was specifically related to the development of depressive-like behavior. IL-4 deficient mice in a BALB/cJ background showed a considerable increase of depressive-like behavior in the forced swim (FST) and tail suspension test (TST) and reduced avoidance behavior in an active avoidance task. Prior conditioning with unescapable foot shocks further decreased avoidance behavior (learned helplessness) but to a similar level as in the wild type strain. IFN-α treatment was not able to further enhance the already increased level of depressive-like behavior in the FST and TST. Thus, IL-4 seems to be a critical participant in the regulation of depressive-like behavior in an untreated baseline condition. Increase of depressive-like behavior during inflammation in wild-type mice might be mediated to some extent by a reduction of IL-4 signaling.

Association of inflammation with specific symptoms of depression in a general population of older people: The English Longitudinal Study of Ageing

Elevated levels of inflammatory markers, such as C-reactive protein, are well documented in people with depression. Few studies have examined whether the association between inflammation and depression is symptom specific, and differs according to antidepressant treatment. Using data from the English Longitudinal Study of Ageing (N=5909), cross-sectional analyses revealed a significant dose-response association between C-reactive protein and the symptoms of fatigue (P<0.001), restless sleep (P=0.03), low energy (P=0.02) and feeling depressed (P=0.04), but not other symptoms. These associations were absent in users of anti-depressant medication. Our findings suggest the C-reactive protein-depression association is symptom-specific and modified by antidepressant treatment.

Inflammation in Depression and the Potential for Anti-Inflammatory Treatment

Accumulating evidence supports an association between depression and inflammatory processes, a connection that seems to be bidirectional. Clinical trials have indicated antidepressant treatment effects for anti-inflammatory agents, both as add-on treatment and as monotherapy. In particular, nonsteroidal anti-inflammatory drugs (NSAIDs) and cytokine-inhibitors have shown antidepressant treatment effects compared to placebo, but also statins, poly-unsaturated fatty acids, pioglitazone, minocycline, modafinil, and corticosteroids may yield antidepressant treatment effects. However, the complexity of the inflammatory cascade, limited clinical evidence, and the risk for side effects stress cautiousness before clinical application. Thus, despite proof-of-concept studies of anti-inflammatory treatment effects in depression, important challenges remain to be investigated. Within this paper, we review the association between inflammation and depression together with the current evidence on use of anti-inflammatory treatment in depression. Based on this, we address the questions and challenges that seem most important and relevant to future studies, such as timing, most effective treatment lengths and identification of subgroups of patients potentially responding better to different anti-inflammatory treatment regimens.

Inflammation and Immune Regulation as Potential Drug Targets in Antidepressant Treatment

Growing evidence supports a mutual relationship between inflammation and major depression. A variety of mechanisms are outlined, indicating how inflammation may be involved in the pathogenesis, course and treatment of major depression. In particular, this review addresses 1) inflammatory cytokines as markers of depression and potential predictors of treatment response, 2) findings that cytokines interact with antidepressants and non-pharmacological antidepressive therapies, such as electroconvulsive therapy, deep brain stimulation and physical activity, 3) the influence of cytokines on the cytochrome (CYP) p450-system and drug efflux transporters, and 4) how cascades of inflammation might serve as antidepressant drug targets. A number of clinical trials have focused on agents with immunmodulatory properties in the treatment of depression, of which this review covers nonsteroidal anti-inflammatory drugs (NSAIDs), cytokine inhibitors, ketamine, polyunsaturated fatty acids, statins and curcumin. A perspective is also provided on possible future immune targets for antidepressant therapy, such as toll-like receptor-inhibitors, glycogen synthase kinase-3 inhibitors, oleanolic acid analogs and minocycline. Concluding from the available data, markers of inflammation may become relevant factors for more personalised planning and prediction of response of antidepressant treatment strategies. Agents with anti-inflammatory properties have the potential to serve as clinically relevant antidepressants. Further studies are required to better define and identify subgroups of patients responsive to inflammatory agents as well as to define optimal time points for treatment onset and duration.

High Kynurenine (a Tryptophan Metabolite) Predicts Remission in Patients with Major Depression to Add-on Treatment with Celecoxib

BACKGROUND

Signs of an inflammatory process have been described in major depression.

METHODS

In a double-blind, randomized study of celecoxib or placebo add-on to reboxetine in 40 depressed patients, celecoxib treatment has beneficial effects. In order to evaluate the tryptophan/kynurenine metabolism and to identify predictors for remission, tryptophan (TRP), kynurenine (KYN), kynurenic acid (KYNA), and quinolinic acid (QUIN) were estimated in the serum of 32 patients before and after treatment and in a group of 20 healthy controls.

RESULTS

KYN levels were significantly lower in patients (p = 0.008), and the QUIN/KYN ratios were significantly higher (p = 0.028). At baseline, the higher KYN/TRP ratio was predictive for remission during celecoxib add-on treatment (p = 0.04) as well as for remission in the overall patient group (p = 0.01). In the placebo group, remitters showed a higher KYNA/QUIN ratio (p = 0.032). In the overall group, remitters showed lower KYNA/KYN (p = 0.035) and QUIN/KYN (p = 0.011) ratios. The lower the formation of downstream metabolites, especially QUIN, the better the treatment outcome.

CONCLUSION

The high KYN/TRP ratio predicted remission after treatment with celecoxib in this small sample of depressed patients. Eventually, the KYN/TRP ratio might be a marker for those patients, which benefit from an additional anti-inflammatory treatment.

Therapeutic Implications of Brain-Immune Interactions: Treatment in Translation

A wealth of data has been amassed that details a complex, yet accessible, series of pathways by which the immune system, notably inflammation, can influence the brain and behavior. These data have opened the window to a diverse array of novel targets whose potential efficacy is tied to specific neurotransmitters and neurocircuits as well as specific behaviors. What is clear is that the impact of inflammation on the brain cuts across psychiatric disorders and engages dopaminergic and glutamatergic pathways that regulate motivation and motor activity as well as the sensitivity to threat. Given the ability to identify patient populations with increased inflammation, the precision of interventions can be further tuned, in conjunction with the ability to establish target engagement in the brain through the use of multiple neuroimaging strategies. After a brief overview of the mechanisms by which inflammation affects the brain and behavior, this review examines the extant literature on the efficacy of anti-inflammatory treatments, while forging guidelines for future intelligent clinical trial design. An examination of the most promising therapeutic strategies is also provided, along with some of the most exciting clinical trials that are currently being planned or underway.

Inflammation Effects on Brain Glutamate in Depression: Mechanistic Considerations and Treatment Implications

There has been increasing interest in the role of glutamate in mood disorders, especially given the profound effect of the glutamate receptor antagonist ketamine in improving depressive symptoms in patients with treatment-resistant depression. One pathway by which glutamate alterations may occur in mood disorders involves inflammation. Increased inflammation has been observed in a significant subgroup of patients with mood disorders, and inflammatory cytokines have been shown to influence glutamate metabolism through effects on astrocytes and microglia. In addition, the administration of the inflammatory cytokine interferon-alpha has been shown to increase brain glutamate in the basal ganglia and dorsal anterior cingulate cortex as measured by magnetic resonance spectroscopy (MRS). Moreover, MRS studies in patients with major depressive disorder have revealed that increased markers of inflammation including C-reactive protein correlate with increased basal ganglia glutamate, which in turn was associated with anhedonia and psychomotor retardation. Finally, human and laboratory animal studies have shown that the response to glutamate antagonists such as ketamine is predicted by increased inflammatory cytokines. Taken together, these data make a strong case that inflammation may influence glutamate metabolism to alter behavior, leading to depressive symptoms including anhedonia and psychomotor slowing.

Neuroimmune Interface in the Comorbidity between Alcohol Use Disorder and Major Depression

Bidirectional communication links operate between the brain and the body. Afferent immune-to-brain signals are capable of inducing changes in mood and behavior. Chronic heavy alcohol drinking, typical of alcohol use disorder (AUD), is one such factor that provokes an immune response in the periphery that, by means of circulatory cytokines and other neuroimmune mediators, ultimately causes alterations in the brain function. Alcohol can also directly impact the immune functions of microglia, the resident immune cells of the central nervous system (CNS). Several lines of research have established the contribution of specific inflammatory mediators in the development and progression of depressive illness. Much of the available evidence in this field stems from cross-sectional data on the immune interactions between isolated AUD and major depression (MD). Given their heterogeneity as disease entities with overlapping symptoms and shared neuroimmune correlates, it is no surprise that systemic and CNS inflammation could be a critical determinant of the frequent comorbidity between AUD and MD. This review presents a summary and analysis of the extant literature on neuroimmune interface in the AUD–MD comorbidity.

Serum cytokines in pediatric neuropsychiatric syndromes: focus on Attention Deficit Hyperactivity Disorder

BACKGROUND

Inflammation may represent a common underlying mechanism in a wide range of diseases, including neuropsychiatric disorders. Cytokine involvement has been investigated in some studies on patients with childhood neuropsychiatric diseases. The aim of this study was to determine whether cytokines are involved in ADHD to provide a rationale for immune-based therapeutic strategies in this disorder.

METHODS

Sixty children were studied: 34 consecutive drug-naïve children with ADHD (30 males and 4 females; mean age of 10.10 years, SD=2.43 age) and 26 healthy control children (22 males and 4 females; mean age of 10.70 years, SD=1.81). All cytokines but IL-2 (IL4-IL6-IL10- IL17-TNFA and IFNG) were studied by ELISAs; IL-2 was instead studied by means of paired anti-cytokine Abs and cytokine standards obtained from PharMingen.

RESULTS

Data reveal higher IL-6 and IL-10 levels in ADHD patients than in the control group (P=0.03). No differences emerged between the two groups for the other cytokines.

CONCLUSIONS

Our study showed an imbalance between pro- and anti-inflammatory cytokines that may play a pivotal role in the pathogenesis of ADHD.

Serum Cytokine Levels in Major Depressive Disorder and Its Role in Antidepressant Response

OBJECTIVE

Cytokines have been reported to have key roles in major depressive disorder (MDD). However, much less is known about cytokines in MDD and antidepressant treatment due to the diversity of cytokines and the heterogeneity of depression. We investigated the levels of cytokines in patients with MDD compared with healthy subjects and their associations with antidepressant response.

METHODS

We investigated the changes of several cytokines (eotaxin, sCD40L, IL-8, MCP-1alpha, TNF-alpha, INF-gamma and MIP-1alpha) by Luminex assay in 66 patients with MDD and 22 healthy controls. The antidepressant response was assessed by 17-item Hamilton Rating Scale for Depression.

RESULTS

We found the levels of sCD40L (p=0.001), IL-8 (p=0.004) and MCP-1 (p=0.03) of healthy controls were significantly higher than those of depressive patients. However, the level of eotaxin and TNF-alpha were not associated with MDD. In addition, we found the level of MCP-1 was significantly changed after antidepressant treatment (p=0.01).

CONCLUSION

These findings suggest the roles of cytokines in MDD are complex, and could vary according to the individual characteristics of each patient. Further studies regarding the relationship between cytokines and MDD will be required.

Are the emergence of affective disturbances in neuropathic pain states contingent on supraspinal neuroinflammation?

Neuro-immune interactions contribute to the pathogenesis of neuropathic pain due to peripheral nerve injury. A large body of preclinical evidence supports the idea that the immune system acts to modulate the sensory symptoms of neuropathy at both peripheral and central nervous system sites. The potential involvement of neuro-immune interactions in the highly debilitating affective disturbances of neuropathic pain, such as depression, anhedonia, impaired cognition and reduced motivation has received little attention. This is surprising given the widely accepted view that sickness behaviour, depression, cognitive impairment and other neuropsychiatric conditions can arise from inflammatory mechanisms. Moreover, there is a set of well-described immune-to-brain transmission mechanisms that explain how peripheral inflammation can lead to supraspinal neuroinflammation. In the last 5years increasing evidence has emerged that peripheral nerve injury induces supraspinal changes in cytokine or chemokine expression and alters glial cell activity. In this systematic review, based on strong preclinical evidence, we advance the argument that the emergence of affective disturbances in neuropathic pain states are contingent on pro-inflammatory mediators in the interconnected hippocampal-medial prefrontal circuitry that subserve affective behaviours. We explore how dysregulation of inflammatory mediators in these networks may result in affective disturbances through a wide variety of neuromodulatory mechanisms. There are also promising results from clinical trials showing that anti-inflammatory agents have efficacy in the treatment of a variety of neuropsychiatric conditions including depression and appear suited to sub-groups of patients with elevated pro-inflammatory profiles. Thus, although further research is required, aggressively targeting supraspinal pro-inflammatory mediators at critical time-points in appropriate clinical populations is likely to be a novel avenue to treat debilitating affective disturbances in neuropathic conditions.

Microglia activation is associated with IFN-α induced depressive-like behavior

Inflammatory immune activation has been frequently associated with the development of major depression. This association was confirmed in patients receiving long-term treatment with pro-inflammatory interferon-α (IFN-α). Microglia, the resident immune cells in the brain, might serve as an important interface in this immune system-to-brain communication. The aim of the present study was to investigate the role of microglia in an IFN-α mouse model of immune-mediated depression. Male BALB/c mice were treated with daily injections of IFN-α for two weeks. Depressive-like behavior was analyzed in the forced swim and tail suspension test. Activation of microglia was measured by flow cytometry. Pro-inflammatory M1 type (MHC-II, CD40, CD54, CD80, CD86, CCR7), anti-inflammatory M2 type (CD206, CD200R), and maturation markers (CD11c, CCR7) were tested, as well as the chemokine receptor CCR2. IFN-α led to a significant increase in depressive-like behavior and expression of the pro-inflammatory surface markers MHC-II, CD86, and CD54, indicating M1 polarization. Because IFN-α-treated mice showed great individual variance in the behavioral response to IFN-α, they were further divided into vulnerable and non-vulnerable subgroups. Only IFN-α vulnerable mice (characterized by their development of depressive-like behavior in response to IFN-α) showed an increased expression of MHC-II and CD86, while CD54 was similarly enhanced in both subgroups. Thus, IFN-α-induced activation of microglia was specifically associated with depressive-like behavior.

PDE4B as a microglia target to reduce neuroinflammation

The importance of microglia in immune homeostasis within the brain is undisputed. Their role in a diversity of neurological and psychiatric diseases as well as CNS injury is the subject of much investigation. Cyclic adenosine monophosphate (AMP) is a critical regulator of microglia homeostasis; as the predominant negative modulator of cyclic AMP signaling within microglia, phosphodiesterase 4 (PDE4) represents a promising target for modulating immune function. PDE4 expression is regulated by inflammation, and in turn, PDE4 inhibition can alter microglia reactivity. As the prototypic PDE4 inhibitor, rolipram, was tested clinically in the 1980s, drug discovery and clinical development of PDE4 inhibitors have been severely hampered by tolerability issues involving nausea and emesis. The two PDE4 inhibitors approved for peripheral inflammatory disorders (roflumilast and apremilast) lack brain penetration and are dose-limited by side effects making them unsuitable for modulating microglial function. Subtype selective inhibitors targeting PDE4B are of high interest given the critical role PDE4B plays in immune function versus the association of PDE4D with nausea and emesis. The challenges and requirements for successful development of a novel brain-penetrant PDE4B inhibitor are discussed in the context of early clinical development strategies. Furthermore, the challenges of monitoring the state of microglia in vivo are highlighted, including a description of the currently available tools and their limitations. Continued drug discovery efforts to identify safe and well-tolerated, brain-penetrant PDE4 inhibitors are a reflection of the confidence in the rationale for modulation of this target to produce meaningful therapeutic benefit in a wide range of neurological conditions and injury. GLIA 2016;64:1698-1709.

Prepregnancy Obesity and a Biobehavioral Predictive Model for Postpartum Depression

OBJECTIVE

To test a predictive model of the associations among prepregnancy body mass index (BMI), third-trimester biological and behavioral variables, and symptoms of depression at 4 weeks postpartum.

DESIGN

Secondary data analysis from a longitudinal, biobehavioral repeated-measures study of women during the third trimester of pregnancy through 6 months postpartum.

SETTING

Communities surrounding a Midwestern and a Western U.S. city.

PARTICIPANTS

Participants were 111 women enrolled during their third trimesters of pregnancy who were studied through 4 weeks postpartum.

METHODS

Whole blood and saliva were used for biological measures, and validated questionnaires were used for behavioral measures. Principal component analysis and path analysis with principal component variables were used to iteratively test the model.

RESULTS

There were three statistically significant direct effects in the model: the path from prepregnancy BMI to inflammation, the path from prepregnancy BMI to stress, and the path from stress to symptoms of depression at 4 weeks postpartum. Indirect effects of prepregnancy BMI on postpartum depression through intervening variables were not statistically significant, nor was the model-based total effect of prepregnancy BMI on postpartum depression.

CONCLUSION

Stress was significantly linked to prepregnancy BMI and postpartum depression. This finding highlights continuing possibilities for improving outcomes for mothers, infants, and families through stress-mitigating preventive strategies.

Mapping inflammation onto mood: Inflammatory mediators of anhedonia

Evidence supports inflammatory involvement in mood and cognitive symptoms across psychiatric, neurological and medical disorders; however, inflammation is not a sensitive or specific characteristic of these diagnoses. The National Institute of Mental Health Research Domain Criteria (RDoC) ask for a shift away from symptom-based diagnoses toward a transdiagnostic neurobiological focus in the study of brain illnesses. The RDoC matrix may provide a useful framework for integrating the effects of inflammation on brain function. Based on preclinical and clinical findings, relevant relationships span negative and positive valence systems, cognitive systems, systems for social processes and arousal/regulatory systems. As an exemplar, we consider the psychopathological domain of anhedonia, conceptualizing the relevance of inflammation (e.g., cellular immunity) and downstream processes (e.g., indoleamine 2,3-dioxygenase activation and oxidative inactivation of tetrahydrobiopterin) across RDoC units of analysis (e.g., catecholamine neurotransmitter molecules, nucleus accumbens medium spiny neuronal cells, dopaminergic mesolimbic and mesocortical reward circuits, animal paradigms, etc.). We discuss implications across illnesses affecting the brain, including infection, major depressive disorder, stroke, Alzheimer's disease and type 2 diabetes.

Therapeutic effects of minocycline on mild-to-moderate depression in HIV patients: a double-blind, placebo-controlled, randomized trial

Patients with the HIV infection are at high risk for developing depression. The aim of this study was to investigate the safety and efficacy of antidepressant effects of minocycline on HIV patients with depression. Forty-six HIV patients, with mild-to-moderate depression and a Hamilton Depression Rating Scale (HDRS) up to 18, participated in a parallel, randomized, double-blind, placebo-controlled trial and underwent 6 weeks of treatment with either minocycline (100 mg twice daily) or placebo in the same manner. Patients were assessed using HDRS at baseline and at weeks 3 and 6. The primary outcome measure was to evaluate the efficacy of minocycline in improving depressive symptoms. General linear model repeated measures showed significant effect for time × treatment interaction on the HDRS score during the trial course [F(2, 88)=7.50, P=0.001]. There was no significant difference between the two groups regarding adverse events. No serious adverse event was reported. The administration of 100 mg minocycline twice daily seems to be safe and effective in improving depressive symptoms in HIV/AIDS patients with mild-to-moderate depression.

Systematic Review of Metabolic Syndrome Biomarkers: A Panel for Early Detection, Management, and Risk Stratification in the West Virginian Population

INTRODUCTION

Metabolic syndrome represents a cluster of related metabolic abnormalities, including central obesity, hypertension, dyslipidemia, hyperglycemia, and insulin resistance, with central obesity and insulin resistance in particular recognized as causative factors. These metabolic derangements present significant risk factors for cardiovascular disease, which is commonly recognized as the primary clinical outcome, although other outcomes are possible. Metabolic syndrome is a progressive condition that encompasses a wide array of disorders with specific metabolic abnormalities presenting at different times. These abnormalities can be detected and monitored via serum biomarkers. This review will compile a list of promising biomarkers that are associated with metabolic syndrome and this panel can aid in early detection and management of metabolic syndrome in high risk populations, such as in West Virginia.

METHODS

A literature review was conducted using PubMed, Science Direct, and Google Scholar to search for markers related to metabolic syndrome. Biomarkers searched included adipokines (leptin, adiponectin), neuropeptides (ghrelin), pro-inflammatory cytokines (IL-6, TNF-α), anti-inflammatory cytokines (IL-10), markers of antioxidant status (OxLDL, PON-1, uric acid), and prothrombic factors (PAI-1).

RESULTS

According to the literature, the concentrations of pro-inflammatory cytokines (IL-6, TNF-α), markers of pro-oxidant status (OxLDL, uric acid), and prothrombic factors (PAI-1) were elevated in metabolic syndrome. Additionally, leptin concentrations were found to be elevated in metabolic syndrome as well, likely due to leptin resistance. In contrast, concentrations of anti-inflammatory cytokines (IL-10), ghrelin, adiponectin, and antioxidant factors (PON-1) were decreased in metabolic syndrome, and these decreases also correlated with specific disorders within the cluster.

CONCLUSION

Based on the evidence presented within the literature, the aforementioned biomarkers correlate significantly with metabolic syndrome and could provide a minimally-invasive means for early detection and specific treatment of these disorders. Further research is encouraged to determine the efficacy of applying these biomarkers to diagnosis and treatment in a clinical setting.

The Promise and Limitations of Anti-Inflammatory Agents for the Treatment of Major Depressive Disorder

This review provides a critical perspective on recent meta-analyses suggesting that several anti-inflammatory modalities, including nonsteroidal anti-inflammatory drugs (NSAIDs), omega-3 fatty acids, and cytokine antagonist, possess generalizable antidepressant properties. By examining confounds and limitations in the available literature it is suggested that current data suggest that only a sub-group of individuals with major depressive disorder (MDD) have evidence of increased inflammatory biomarkers and it is in these individuals that anti-inflammatory agents show promise for reducing depressive symptoms. The treatment implications of this cautionary perspective are discussed.

Effects of olanzapine on LPS-induced inflammation in rat primary glia cells

Olanzapine (OLZ) is an atypical antipsychotic drug that also has mood-stabilizing effects. The mechanism of action of OLZ is not fully understood. Accumulating data suggest that inflammation plays a role in the pathophysiology of mental disorders and that psychotropic drugs exhibit some anti-inflammatory properties. This study was undertaken to examine the effects of OLZ on LPS-induced inflammation in rat primary glia cells. Glia cells were extracted from newborn rat brains. OLZ (1 or 50 µM) was added to culture medium at 6 or 72 h before addition of LPS for another 18 h, and levels of IL-10, prostaglandin (PG) E2, NO and TNF-α, and expression of cyclo-oxygensase (COX)-2 and inducible NO synthase (iNOS) were determined. Treatment with 50 µM OLZ (but not 1 µM) significantly decreased LPS-induced secretion of IL-10, PGE2 and TNF-α. In contrast, 50 µM OLZ significantly increased NO levels. OLZ did not alter the expression of COX-2 or iNOS in LPS-treated cells. These results suggest that OLZ differently affects the secretion of inflammatory mediators. Most of the significant effects of OLZ were obtained when 50 µM was used, which is a high and probably therapeutically irrelevant concentration. Therefore, under the conditions used in the present study OLZ seemed to lack a potent anti-inflammatory effect.

Assessing brain immune activation in psychiatric disorders: clinical and preclinical PET imaging studies of the 18-kDa translocator protein

Accumulating evidence from different lines of research suggests an involvement of the immune system in the pathophysiology of several psychiatric disorders. During recent years, a series of positron emission tomography (PET) studies have been published using radioligands for the translocator protein (TSPO) to study microglia activation in schizophrenia, bipolar I disorder, major depression, autism spectrum disorder, and drug abuse. The results have been somewhat conflicting, which could be due to differences both in patient sample characteristics and in PET methods. In particular, further work is needed to address both methodological and biological sources of variability in TSPO levels, a process in which the use of animal models and small animal PET systems can be a valuable tool. Given this development, PET studies of immune activation have the potential to further increase our understanding of disease mechanisms in psychiatric disorders, which is a requisite in the search for new treatment approaches. Furthermore, molecular imaging could become an important clinical tool for identifying specific subgroups of patients or disease stages that would benefit from treatment targeting the immune system.

Simvastatin versus atorvastatin for improving mild to moderate depression in post-coronary artery bypass graft patients: A double-blind, placebo-controlled, randomized trial

BACKGROUND

A decreased risk of developing depression has been reported among statin users. Aside from their lipid-lowering effects, statins are considered immunomodulatory agents and have protective effects against oxidative stress and inflammation which are well known for their association with depression. The aim of the present study was to compare the probable antidepressant effects of simvastatin and atorvastatin among post-coronary artery bypass graft (CABG) surgery patients with high and low potentials for blood-brain-barrier penetration, respectively.

METHOD

Forty-six outpatients who had undergone CABG in the last 6 months and suffered from mild to moderate depression participated in a parallel, double-blind, placebo-controlled trial, and were randomized to undergo 6 weeks of treatment with either simvastatin (20mg/day) or atorvastatin (20mg/day). Participants were evaluated using Hamilton depression rating scale (HDRS) at baseline and weeks 3 and 6. The primary outcome was to evaluate the efficacy of simvastatin in improving the depressive symptoms.

RESULT

General linear model repeated measures demonstrated significant effect for time×treatment interaction on the HDRS scores [F (1.62, 71.06)=3.41, P=0.048]. There was no significant difference between the treatment groups regarding the adverse events. No one experienced serious adverse event.

LIMITATION

The limitations of the present study were its small sample size and the short-term follow-up period.

CONCLUSION

Treatment with simvastatin seems to be well tolerated with superior antidepressant effects compared to atorvastatin in post-CABG patients. Long-term outcomes of this practice and its probable influence on other psychological aspects are yet to be investigated in future studies.

TRIAL REGISTRATION

Iranian registry of clinical trials (http://www.irct.ir): IRCT201410271556N68.

Celecoxib adjunctive therapy for acute bipolar mania: a randomized, double-blind, placebo-controlled trial

OBJECTIVES

Recent research has focused on the inflammatory cascade as a key culprit in the etiology of bipolar disorder. We hypothesized that celecoxib, via its anti-inflammatory properties, may have a therapeutic role in mood disorder.

METHODS

Forty-six inpatients with the diagnosis of acute bipolar mania without psychotic features participated in a parallel, randomized, double-blind, placebo-controlled trial, and underwent six weeks of treatment with either celecoxib (400 mg daily) or placebo as an adjunctive treatment to sodium valproate. Patients were evaluated using the Young Mania Rating Scale (YMRS) and Hamilton Depression Rating Scale (HDRS). The primary outcome measure with respect to efficacy was the mean decrease in YMRS score from baseline to the study endpoint, which was compared between the two groups.

RESULTS

A significant difference was observed in the change in YMRS scores on Day 42 compared to baseline in the two groups (p < 0.001). The changes at the endpoint compared to baseline were -29.78 ± 21.78 (mean ± standard deviation) and -21.78 ± 7.16 for the celecoxib and placebo groups, respectively. A significantly higher remission rate was observed in the celecoxib group (87.0%) than the placebo group (43.5%) at Week 6 (p = 0.005). General linear model repeated measures demonstrated a significant effect for the time × treatment interaction on the YMRS scores [F(2.27,99.98) = 6.67, p = 0.001].

CONCLUSIONS

Celecoxib is an effective adjuvant therapy in the treatment of manic episodes (without psychotic features) of bipolar mood disorder. The mood-stabilizing role of the drug might be mediated via its action on the inflammatory cascade.

Inflammation and depression: combined use of selective serotonin reuptake inhibitors and NSAIDs or paracetamol and psychiatric outcomes

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) and paracetamol have been shown to yield the potential of adjunctive antidepressant treatment effects to selective serotonin reuptake inhibitors (SSRIs); however, when investigating treatment effects of concomitant use, simultaneous evaluation of potential adverse events is important. The objective was thus to investigate treatment effectiveness and safety aspects of concomitant SSRI use with NSAIDs or paracetamol.

METHODS

Within a 25% random sample of the Danish population, we identified all incident SSRI users between 1997 and 2006 (N = 123,351). Effectiveness and safety measures were compared between periods of SSRI use only and periods of combined SSRI and NSAID or paracetamol use by applying Cox regression.

RESULTS

Among 123,351 SSRI users (follow-up: 53,697.8 person-years), 21,666 (17.5%) used NSAIDs and 10,232 (8.3%) paracetamol concomitantly. Concomitant NSAID use increased the risk of any psychiatric contact [Hazard rate ratio (95%-confidence interval): 1.22 (1.07; 1.38)] and with depression [1.31 (1.11; 1.55)]. Low-dose acetylsalicylic acid reduced the risk of psychiatric contact in general [0.74 (0.56; 0.98)] and with depression [0.71 (0.50; 1.01)]. Ibuprofen reduced the risk of psychiatric contacts [0.76 (0.60; 0.98)]. Concerning safety, paracetamol was associated with increased mortality [3.18 (2.83; 3.58)], especially cardiovascular [2.51 (1.93; 3.28)]. Diclofenac [1.77 (1.22; 2.55)] and the selective COX-2 inhibitors [1.75 (1.21; 2.53)] increased mortality risks.

CONCLUSIONS

Concomitant use of SSRIs and NSAIDs occurred frequently, and effectiveness and safety outcomes varied across individual NSAIDs. Especially low-dose acetylsalicylic acid may represent an adjunctive antidepressant treatment option. The increased mortality risk of concomitant use of paracetamol needs further investigation.

Celecoxib Versus Diclofenac in Mild to Moderate Depression Management Among Breast Cancer Patients: A Double-Blind, Placebo-Controlled, Randomized Trial

BACKGROUND

Depression is a well-known complication of breast cancer, which is known to adversely affect quality of life, prognosis, and survival in breast cancer patients. Celecoxib, a nonsteroidal anti-inflammatory drug, which acts via the selective inhibition of cyclo-oxygenase (COX)-2, has been shown to have antidepressive effects.

OBJECTIVES

Here, we aimed to compare the efficacy and safety of celecoxib, a selective inhibitor of COX-2, with diclofenac, a nonselective inhibitor of both COX-1 and COX-2 in reducing depressive symptoms and pain in breast cancer patients.

METHODS

A total of 52 outpatients with breast cancer with mild to moderate depression, who suffered from pain and needed analgesics, participated in the trial and underwent 6 weeks of treatment with either celecoxib (200 mg twice daily) or diclofenac (50 mg twice daily). Participants were investigated using the Hamilton Depression Rating Scale (HDRS). The primary outcome measure was to compare the antidepressant effects of celecoxib and diclofenac.

RESULTS

Repeated-measures analysis demonstrated significant effect for Time × Treatment interaction on the HDRS scores: F(1.76, 87.85) = 9.66; P < 0.001. By study conclusion, greater improvement was observed in the HDRS score of the celecoxib group compared with the diclofenac group (P = 0.002). No one experienced remission (HDRS ≤ 7) in either group. Frequencies of adverse events were not significantly different between groups.

CONCLUSION

Celecoxib seems to possess superior antidepressive effects compared with diclofenac in breast cancer patients with mild to moderate depression.

Diene Valepotriates from Valeriana glechomifolia Prevent Lipopolysaccharide-Induced Sickness and Depressive-Like Behavior in Mice

Valeriana glechomifolia, a native species from southern Brazil, presents antidepressant-like activity and diene valepotriates (VAL) contribute to the pharmacological properties of the genus. It is known that depression can develop on an inflammation background in vulnerable patients and antidepressants present anti-inflammatory properties. We investigated the effects of VAL (10 mg/kg, p.o.) on sickness and depressive-like behaviors as well as proinflammatory cytokines (IL-1β and TNF-α) and BDNF expression in the cortex of mice exposed to a 5 min swimming session (as a stressful stimulus) 30 min before the E. coli LPS injection (600 µg/kg, i.p.). The forced swim + LPS induced sickness and depressive-like behaviors, increased the cortical expression of IL-1β and TNF-α, and decreased BDNF expression. VAL was orally administered to mice 1 h before (pretreatment) or 5 h after (posttreatment) E. coli LPS injection. The pretreatment with VAL restored the behavioral alterations and the expression of cortical proinflammatory cytokines in LPS-injected animals but had no effects on BDNF expression, while the posttreatment rescued only behavioral alterations. Our results demonstrate for the first time the positive effects of VAL in an experimental model of depression associated with inflammation, providing new data on the range of action of these molecules.

Celecoxib for the treatment of mild-to-moderate depression due to acute brucellosis: a double-blind, placebo-controlled, randomized trial

WHAT IS KNOWN AND OBJECTIVE

Depression is a debilitating complication of brucellosis and how best to treat this is a matter of debate. Inflammatory processes are involved in the pathogenesis of both brucellosis and depression. Therefore, we hypothesized that celecoxib could be beneficial for the treatment of depression due to brucellosis.

METHODS

Forty outpatients with depression due to brucellosis with a Hamilton Depression Rating Scale score (HDRS) <19 participated in a randomized, double-blind, placebo-controlled trial and underwent 8 weeks of treatment with either celecoxib (200 mg bid) or placebo as an adjunctive to antibiotic therapy. Patients were evaluated using HDRS at baseline and weeks 4 and 8.

RESULT AND DISCUSSION

Repeated-measures analysis demonstrated significant effect for time × treatment interaction on the HDRS score [F (1·43, 57·41) = 37·22, P < 0·001]. Significantly greater response to treatment occurred in the celecoxib group than in the placebo group at the study end [10 patients (50%) vs. no patient (0%), respectively, P < 0·001]. No serious adverse event was observed.

WHAT IS NEW AND CONCLUSION

Celecoxib is a safe and effective treatment for depression due to brucellosis when compared with placebo.

Simvastatin as an adjuvant therapy to fluoxetine in patients with moderate to severe major depression: A double-blind placebo-controlled trial

Statins have been shown to decrease depressive symptoms in certain groups of patients, an effect that is mostly attributed to their anti-inflammatory and neurotransmitter modulatory potentials. We aimed to investigate the antidepressant effects of simvastatin as an adjuvant therapy in patients with moderate to severe depression. In this double-blind placebo-controlled clinical trial, 48 patients were randomly allocated to receive simvastatin or placebo as an adjunct to fluoxetine for six weeks. Patients were evaluated with the Hamilton Depression Rating Scale (HDRS) at baseline and weeks 2, 4 and 6. Probable clinical and laboratory adverse events were also monitored and compared between the two groups. Simvastatin-treated patients experienced significantly more reductions in HDRS scores compared to the placebo group by the end of the trial (p=0.02). Early improvement and response rates were significantly greater in the simvastatin group than the placebo group (p=0.02 and p=0.01, respectively) but remission rate was not significantly different between the two groups (p=0.36). No serious adverse event was reported during this trial. In conclusion, simvastatin seems to be a safe and effective adjuvant therapy for patients suffering from major depressive disorder. However, more confirmatory studies are warranted.

Vitamin C as an adjuvant for treating major depressive disorder and suicidal behavior, a randomized placebo-controlled clinical trial

Background

There are some animal studies suggesting the possible role of vitamin C for treating depression. However, the efficacy of vitamin C for treating adult patients with major depressive disorder (MDD) has never been examined.

Methods

This 8-week randomized double-blind placebo-controlled clinical trial included adult patients with major depressive disorder according to DSM-IV diagnostic criteria. Twenty-one patients in the treatment group received citalopram plus vitamin C and the 22 patients in the control group received citalopram plus placebo. The Hamilton Depression Rating Scale was used to measure depressive symptoms at baseline, week 2, week 4, and week 8. We also checked for the presence of adverse effects.

Results

While depression symptoms decreased in both groups during this trial, there was no statistically significant difference between the 2 groups (P = .5). The rate of remission, partial response, and complete response was not different between the two groups. The rate of adverse effects were not different between the two groups.

Conclusion

Adding vitamin C to citalopram did not increase the efficacy of citalopram in MDD patients. Vitamin C plus citalopram is as effective as placebo plus citalopram for treating adult patients with suicidal behavior. No serious adverse effect for this combination was identified during this trial.

Trial registration

This trial was registered at http://www.irct.ir. The registration number of this trial was: IRCT201312263930N31. Date registered: 5 July 2014.

A critical review of the efficacy of non-steroidal anti-inflammatory drugs in depression

Non-steroidal anti-inflammatory drugs (NSAIDs) require further investigation given mixed results regarding efficacy. We critically and systematically reviewed the literature to determine whether selective COX-2 and non-selective COX inhibitor NSAIDs as adjuncts or monotherapy affect depressive symptoms. Electronic databases including Embase, PsycINFO, Ovid Medline, ScienceDirect, Google Scholar and the Cochrane Central Register of Controlled Trials database were searched up to September 2013. We utilised randomised controlled trials (RCTs), cohort studies and an open label study examining the efficacy of NSAIDs as adjuncts or monotherapy on depressive symptoms in subjects without major comorbidities. There were a total of 6 studies exploring the efficacy of selective COX-2 inhibitor NSAIDs on depressive symptoms with a total of 2706 subjects from 6 RCTs. 4 of the RCTs showed a significant effect of NSAIDs; 2 demonstrated no effect. There were a total of 5 studies exploring the efficacy of non-selective COX inhibitor NSAIDs on depressive symptoms with a total of 7978 subjects. There was 1 RCT, 3 cohort studies and 1 open label pilot study. The RCT failed to show a significant result. 1 of the retrospective cohort studies showed a positive result, with the other 2 showing no effect. The pilot study showed a positive result for NSAIDs. These studies demonstrated significant methodological heterogeneity (i.e. age range, sex, presence of antidepressant use, method of depression measure, severity of depressive symptoms, duration and study design (RCT vs. cohort)). The efficacy of NSAIDs on depressive symptoms appears negligible, however firm conclusions are difficult given the inconsistent findings and substantial methodological heterogeneity. Further high quality research is needed to explore NSAID efficacy in clinical and biological subtypes of depression, as monotherapy and adjunct with various antidepressants, and across various ages.

Pioglitazone adjunctive therapy for depressive episode of bipolar disorder: a randomized, double-blind, placebo-controlled trial

BACKGROUND

The antidepressive effect of pioglitazone has been noted in patients with major depressive disorder in absence of metabolic syndrome. This study was conducted to evaluate the safety and efficacy of pioglitazone in patients with bipolar depression without concomitant metabolic syndrome or diabetes.

METHOD

Forty-eight outpatients with the diagnosis of bipolar I disorder and a major depressive episode participated in a parallel, randomized, double-blind, placebo-controlled trial, and 44 patients underwent 6-week treatment with either pioglitazone (30 mg/day) or placebo as an adjunctive treatment to lithium. Therapeutic serum lithium levels of 0.6-0.8 mEq/L were required for two or more consecutive weeks immediately before starting pioglitazone and during the 6-week study. Patients were evaluated using Hamilton Depression Rating Scale (HDRS) and Young Mania Rating Scale (YMRS) at baseline and weeks 1, 2, 4, and 6. The primary outcome was to evaluate the efficacy of pioglitazone in improving the depressive symptoms.

RESULT

General linear model repeated measures showed significant effect for time × treatment interaction on the HDRS scores [F(2.78, 116.65) = 4.77, P = .005]. Significantly greater reduction was observed in HDRS scores in the pioglitazone group than the placebo group from baseline HDRS score at weeks 2, 4, and 6, P = .003, .006, and .006, respectively. No serious adverse event was observed.

CONCLUSION

This study showed that pioglitazone could be a tolerable and effective adjunctive therapy for improving depressive symptoms in bipolar disorder without type 2 diabetes or metabolic syndrome.

Elevated level of DNA damage and impaired repair of oxidative DNA damage in patients with recurrent depressive disorder

BACKGROUND

Depressive disorder (DD), including recurrent DD (rDD), is a severe psychological disease, which affects a large percentage of the world population. Although pathogenesis of the disease is not known, a growing body of evidence shows that inflammation together with oxidative stress may contribute to development of DD. Since reactive oxygen species produced during stress may damage DNA, we wanted to evaluate the extent of DNA damage and efficiency of DNA repair in patients with depression.

MATERIAL AND METHODS

We measured and compared the extent of endogenous DNA damage--single- and double-strand breaks, alkali-labile sites, and oxidative damage of the pyrimidines and purines--in peripheral blood mononuclear cells isolated from rDD patients (n=40) and healthy controls (n=46) using comet assay. We also measured DNA damage evoked by hydrogen peroxide and monitored changes in DNA damage during repair incubation.

RESULTS

We found an increased number DNA breaks, alkali-labile sites, and oxidative modification of DNA bases in the patients compared to the controls. Exposure to hydrogen peroxide evoked the same increased damage in both groups. Examination of the repair kinetics of both groups revealed that the lesions were more efficiently repaired in the controls than in the patients.

CONCLUSIONS

For the first time we showed that patients with depression, compared with non-depresses individuals, had more DNA breaks, alkali-labile sites, and oxidative DNA damage, and that those lesions may be accumulated by impairments of the DNA repair systems. More studies must be conducted to elucidate the role of DNA damage and repair in depression.

Novel investigational drugs targeting IL-6 signaling for the treatment of depression

INTRODUCTION

Elevated levels of IL-6 have been implicated in the pathophysiology and treatment of major depressive disorder (MDD). Convergent evidence suggests that IL-6 primarily mediates proinflammatory functions via the soluble IL-6 receptor/trans-signaling, and anti-inflammatory functions via a transmembrane receptor (IL-6R). A targeted approach to selectively inhibit IL-6 trans-signaling may offer putative antidepressant effects.

AREAS COVERED

This review addresses three primary domains. The first focuses on the biological role of IL-6 within inflammation and its signal transduction pathways. The second addresses the potential contributions of IL-6 to the pathophysiology of MDD, and the mechanisms that may mediate these effects. Finally, the article outlines the therapeutic benefits of incorporating anti-inflammatory properties into the pharmacological treatment of MDD, and proposes inhibition of IL-6 signaling as a viable treatment strategy.

EXPERT OPINION

To improve drug development for the treatment of MDD, there is a critical need to identify promising targets. Target identification will require guidance from a strategic framework such as The Research Domain Criteria, and convincing evidence relating known targets to brain function under both physiological and pathological conditions. Although current evidence provides rationale for administering anti-IL-6 treatments in MDD, further studies confirming safety, target affinity and therapeutic benefits are warranted.