Effect of Agomelatine and Fluoxetine on HAM-D Score, Serum Brain-Derived Neurotrophic Factor, and Tumor Necrosis Factor- Level in Patients With Major Depressive Disorder With Severe Depression

Comparing the effect of fluoxetine, escitalopram, and sertraline, on the level of BDNF and depression in preclinical and clinical studies: a systematic review

Brain-derived neurotrophic factor (BDNF) dysfunction is one of the most important mechanisms underlying depression. It seems that selective serotonin reuptake inhibitors (SSRIs) improve depression via affecting BDNF level. In this systematic review, for the first time, we aimed to review the effect of three SSRIs including fluoxetine, escitalopram, and sertraline, on both depression and BDNF level in preclinical and clinical studies. PubMed electronic database was searched, and 193 articles were included in this study. After reviewing all manuscripts, only one important difference was found: subjects. We found that SSRIs induce different effects in animals vs. humans. Preclinical studies showed many controversial effects, while human studies showed only two effects: improvement of depression, with or without the improvement of BDNF. However, most studies used chronic SSRIs treatment, while acute SSRIs were not effectively used and evaluated. In conclusion, it seems that SSRIs are reliable antidepressants, and the improvement effect of SSRIs on depression is not dependent to BDNF level (at least in human studies).

Evidence of the Immunomodulatory Effects of Selective Serotonin Reuptake Inhibitors in Patients With Depression Through a Systematic Review

Depression is a common illness, affecting >264 million people worldwide. According to the literature, depression patients have baseline subclinical inflammation. The immunomodulatory effects of antidepressants, such as selective serotonin reuptake inhibitors (SSRIs), are largely unclear and poorly understood. Using evidence-based medicine, this study aimed to determine the immunomodulatory effects of SSRIs by assessing changes in immunomodulatory markers following SSRI treatment. Using the PubMed website, a literature search was conducted with various terminologies related to the treatment of depression and various markers of inflammation. Out of 387 retrieved articles, after critical appraisal and screening based on inclusion and exclusion criteria, 17 were selected. Qualitative synthesis and quantitative analysis were carried out. RevMan 5 software was used to synthesize and evaluate the data. Microsoft Word and Excel (Microsoft Corporation, Redmond, Washington, United States) were used for generating tables and figures. We extracted data from a total of 839 patients in 17 studies. A highly significant reduction in interleukins-6 (IL-6) (standardised mean difference (SMD) = 1.32 (95% confidence interval (CI): 0.58, 2.06), Z = 3.48, P = 0.0005), a significant reduction in tumor necrosis factor-alpha (TNF-α) (SMD = 1.29 (95% CI: 0.19, 2.39), Z = 2.30, P = 0.02) but no change in overall C-reactive protein (CRP) (SMD = 0.40 (95% CI: -0.26, 1.07), Z = 1.19, P = 0.23) levels were observed by using the random-effects model. There was substantial heterogeneity found between the studies. SSRIs have an immunomodulatory effect in patients with depression by significantly reducing the peripheral pro-inflammatory cytokine markers of IL-6 and TNF-α, which may contribute to ameliorating the response to antidepressant drug treatment. In contrast, no effects of SSRIs on acute-phase protein CRP were found.

Sertraline with desvenlafaxine and sertraline with mirtazapine as treatment initiation in MDD patients with moderate to severe depression and effect on inflammatory markers

BACKGROUND

This study evaluated the effect of sertraline with desvenlafaxine and sertraline with mirtazapine on HAM-D score and inflammatory markers (IL-6 and TNF-α levels) in major depressive disorder.

METHODS

Patients (18-60 years) with MDD diagnosed by DSM-V criteria and HAM-D score 18 or more were included (n = 60). Group A patients (n = 30) received sertraline 50 mg/day and desvenlafaxine 50 mg/day. Group B patients (n = 30) received sertraline 50 mg/day and mirtazapine 30 mg/day. All patients were followed up for 8 weeks for the evaluation of clinical efficacy, safety, serum IL-6, and TNF-α levels.

RESULTS

Our study showed a comparatively similar and statistically significant (p < 0.05) reduction in HAM-D score in both groups in the 4th and 8th week of the treatment. Both drug combinations significantly (p < 0.05) decreased serum IL-6 and TNF-α after 8 weeks of treatment.

CONCLUSION

The present study suggests that the combination therapy (as treatment initiation) with sertraline and desvenlafaxine, and sertraline with mirtazapine is effective and well tolerated in MDD patients with moderate to severe depression, and their therapeutic efficacy is accompanied by decreased inflammatory markers (serum IL-6 and TNF-α).

Potential biomarkers and therapeutic targets for obsessive compulsive disorder: Evidences from clinical studies

Obsessive compulsive disorder (OCD) is a prevalent behavioral disorder with a complex etiology. However, the underlying pathogenic molecular pathways and the associated risk factors are largely obscure. This has hindered both the identification of relevant prognostic biomarkers and the development of effective treatment strategies. Because of the diverse range of clinical manifestations, not all patients benefit from therapies currently practiced in the clinical setting. Nevertheless, several lines of evidence indicate that neurotrophic, neurotransmitter, and oxidative signaling are involved in the pathophysiology of OCD. Based upon evidences from clinical (and pre-clinical studies), the present review paper sets out to decipher the utilities of three parameters (i.e. brain-derived neurotrophic factor; BDNF, noradrenalin-synthesizing enzyme dopamine beta-hydroxylase; DBH; and oxidative damage marker malondialdehyde; MDA) as diagnostic peripheral biomarkers as well as bio-targets for therapeutic strategies. While the data indicates promising results, there is necessitation for future studies to further confirm and establish these. Further, based again on the available clinical data, we investigated the possibilities of exploiting the etiological links between disruptions in the sleep-wake cycle and insulin signaling, and OCD for the identification of potential anti-OCD ameliorative agents with the ability to elicit multimodal effects, including attenuation of the alterations in BDNF, noradrenergic and redox pathways. In this respect, agomelatine and metformin may represent particularly interesting candidates; however, further clinical studies are warranted to establish these as singular or complementary medications in OCD subjects.

Research Progress on the Antidepressant Effects of Baicalin and Its Aglycone Baicalein: A Systematic Review of the Biological Mechanisms

Depression is the most prevalent mental disorder, affecting more than 300 million adults worldwide each year, which can lead to serious economic and social problems. Antidepressants are usually the first-line treatment for depression, however, traditional antidepressants on the market have the disadvantage of low remission rates and may cause side effects to patients, therefore, the current focus in the field of depression is to develop novel therapeutic agents with high remission rates and few side effects. In this context, the antidepressant effects of natural compounds have received attention. Baicalin (baicalein-7-O-glucuronide) and its aglycone baicalein (5,6,7-trihydroxyflavone) are flavonoid compounds extracted from the root of Scutellaria baicalensis. Although lacking the support of clinical data, they have been shown to have significantly promising antidepressant activity in many preclinical studies through various rodent models of depression. This paper reviews the antidepressant effects of baicalin and baicalein in experimental animal models, with emphasis on summarizing the molecular mechanisms of their antidepressant effects including regulation of the HPA axis, inhibition of inflammation and oxidative stress, reduction of neuronal apoptosis and promotion of neurogenesis, as well as amelioration of mitochondrial dysfunction. Controlled clinical trials should be conducted in the future to examine the effects of baicalin and baicalein on depression in humans.

Association between programmed death-1 pathway and major depression

OBJECTIVES

Major depression (MD) may be associated with inflammation and immunity. PD-1 (programmed death-1), PD-L1 (programmed death-ligand 1) and PD-L2 (programmed death-ligand 2) are among the inhibitory immune mediators on the PD-1 pathway. However, previous data regarding the association between MD and PD-1 pathway were still scarce; therefore, we investigated the association of PD-1 pathway with MD.

METHODS

During a period of 2 years, patients with MD and healthy controls were recruited from a medical centre in this study. The diagnosis of MD was established according to the DSM-5 criteria. The severity of MD was assessed with 17-item Hamilton Depression Rating Scale. PD-1, PD-L1 and PD-L2 were detected in peripheral blood from MD patients after 4 weeks of treatment with antidepressant drugs.

RESULTS

A total of 54 patients with MD and 38 healthy controls were recruited. According to the analyses, there is a significantly higher PD-L2 level in MD than in healthy controls and lower PD-1 level after age and BMI adjustment. Besides, moderately positive correlation between HAM-D scores and PD-L2 level was found.

CONCLUSIONS

It was found that PD-1 pathway might play an important role in MD. We need a large sample to prove these results in the future.

The role of the circadian system in the etiology of depression

Circadian rhythms have evolved in almost all organisms enabling them to anticipate alternating changes in the environment. As a consequence, the circadian clock controls a broad range of bodily functions including appetite, sleep, activity and cortisol levels. The circadian clock synchronizes itself to the external world mainly by environmental light cues and can be disturbed by a variety of factors, including shift-work, jet-lag, stress, ageing and artificial light at night. Interestingly, mood has also been shown to follow a diurnal rhythm. Moreover, circadian disruption has been associated with various mood disorders and patients suffering from depression have irregular biological rhythms in sleep, appetite, activity and cortisol levels suggesting that circadian rhythmicity is crucially involved in the etiology and pathophysiology of depression. The aim of the present review is to give an overview and discuss recent findings in both humans and rodents linking a disturbed circadian rhythm to depression. Understanding the relation between a disturbed circadian rhythm and the etiology of depression may lead to novel therapeutic and preventative strategies.

Cefaclor causes vagus nerve-mediated depression-like symptoms with gut dysbiosis in mice

Antibiotics are increasingly recognized as causing neuropsychiatric side effects including depression and anxiety. Alterations in central serotonin and 5-HT receptor expression are implicated in the pathogenesis of anxiety and depression, which are highly comorbid with gastrointestinal disorders. Nevertheless, it is still unclear how antibiotics can cause anxiety and depression. In this study, oral administration of cefaclor, a second-generation cephalosporin antibiotic, induced anxiety- and depression-like behaviors and colitis with gut microbiota alteration in mice. Cefaclor reduced serotonin levels and fluctuated 5-HT receptor mRNA expressions such as Htr1a, Htr1b, and Htr6 in the hippocampus. Vagotomy attenuated the cefaclor-induced anxiety- and depression-like symptoms, while the cefaclor-induced changes in gut bacteria alteration and colitis were not affected. Fluoxetine attenuated cefaclor-induced anxiety- and depression-like behaviors. Furthermore, fluoxetine decreased cefaclor-resistant Enterobacteriaceae and Enterococcaceae. Taken together, our findings suggest that the use of antibiotics, particularly, cefaclor may cause gut dysbiosis-dependent anxiety and depression through the microbiota-gut-blood-brain and microbiota-gut-vagus nerve-brain pathway. Targeting antibiotics-resistant pathogenic bacteria may be a promising therapeutic strategy for the treatment of anxiety and depression.

Interactions between symptoms and psychological status in irritable bowel syndrome: An exploratory study of the impact of a probiotic combination

BACKGROUND

Stress is an exacerbator of irritable bowel syndrome (IBS) symptoms, and anxiety and depression are co-morbidities. Bifidobacterium longum strains 1714® and 35642® attenuate stress responses in healthy people and reduce symptoms in IBS, respectively. Here, we explore relationships between the psychological and visceral effects of the two strains (COMBO) in IBS subjects and biomarkers of stress and inflammation.

METHODS

We recruited 40 patients with IBS (Rome III) and mild to moderate anxiety (HADS-A) and/or depression (HADS-D) and 57 asymptomatic female controls with low or moderate stress. IBS patients were fed COMBO (1 × 10⁹ cfu/day) for 8 weeks with an 8-week washout. IBS symptoms, psychometric measures, salivary cortisol awakening response (CAR), and plasma inflammatory biomarkers were assessed every 4 weeks.

KEY RESULTS

Compared to healthy controls, IBS subjects had a blunted CAR. Treatment with COMBO restored CAR and improved IBS symptoms compared to baseline during the treatment phase. The COMBO reduced HADS-D, HADS-A score, and TNF-α, while sleep quality improved significantly from baseline to the end of the intervention. Surprisingly, these parameters improved further once treatment ended and maintained this improvement by Week 16.

CONCLUSIONS AND INFERENCES

These findings suggest that the stress response is a major driver of IBS symptoms. The time course of the beneficial effect of COMBO on IBS symptoms suggests that this is achieved through a restoration of the stress response. In contrast, the time course of the effects of COMBO on anxiety and depression in IBS paralleled an anti-inflammatory effect as indicated by a reduction in circulating levels of TNF-α.

Fluoxetine modulates the pro-inflammatory process of IL-6, IL-1β and TNF-α levels in individuals with depression: a systematic review and meta-analysis

Clinical evidence suggests that inflammation is a key factor to understand the causes of depressive symptoms. Fluoxetine is one of the main first-line medications used for depression, and it is hypothesized that it participates in the decrease of pro-inflammatory cytokines. Hence, our aim was to perform a meta-analysis and systematic review to understand the interaction of fluoxetine in the IL-1β, IL-6 and TNF-α inflammatory process. Studies identified in PubMed and Scopus databases were used to perform a meta-analysis via the Comprehensive software. Standardized mean difference (SMD) was used as a summary statistic. The analysis included a total of 292 individuals with major depressive disorder who received fluoxetine for a period longer than 6 weeks; additionally, IL-1β, IL-6 or TNF-α levels were measured at the end of the antidepressant treatment. The findings were significant revealed decreased levels of the cytokines studied. In conclusion, the pooled data suggest that fluoxetine treatment improved depressive symptomatology by the modulation of pro-inflammatory process such as IL-1β, IL-6 or TNF-α.

Tetragonia tetragonioides Relieves Depressive-Like Behavior through the Restoration of Glial Loss in the Prefrontal Cortex

Tetragonia tetragonioides, which is a halophyte and grows widely in Asian-Pacific regions, has been used for the treatment of digestive disorders in traditional oriental medicine. This study examined the potential antidepressant effect of Tetragonia tetragonioides in an astroglial degeneration model of depression, which was established based on the postmortem study of depressive patients' brain presenting diminished astrocytes in the prefrontal cortex. C57BL/6 male mice were exposed to glial ablation in the prefrontal cortex by the administration of the gliotoxin, L-alpha-aminoadipic acid (L-AAA) to induce depression. Tetragonia tetragonioides at doses of 100 mg/kg and 300 mg/kg, imipramine at a dose of 15 mg/kg, and distilled water were orally administrated to mice for 18 days. Behavioral tests including the open field test (OFT), sucrose preference test (SPT), forced swimming test (FST), and tail suspension test (TST) were carried out after 2 days of L-AAA injection. The expression levels of GFAP and NeuN in the prefrontal cortex were determined by immunohistochemistry. Mice subjected to glial ablation in the prefrontal cortex displayed decreased sucrose consumption in SPT and increased immobility time in FST and TST. Treatment with imipramine and Tetragonia tetragonioides remarkably ameliorated the behavioral despair induced by L-AAA. In addition, immunohistochemistry analysis showed that treatment with Tetragonia tetragonioides significantly restored the glial loss as indicated by the elevated GFAP expression level. These findings suggest that Tetragonia tetragonioides exerts an antidepressant effect through the restoration of glial loss under conditions of depression and can be a candidate for an antidepressant agent.

Bupropion monotherapy alters neurotrophic and inflammatory markers in patients of major depressive disorder

BACKGROUND

Emerging hypotheses in the pathophysiology of major depressive disorder (MDD) indicate the role of neurotrophic factors and inflammation. This study assessed the association between therapeutic response of bupropion and serum brain-derived neurotrophic factor (BDNF) and tumour necrosis factor-α (TNF-α) levels in patients with MDD.

METHODS

Thirty patients (aged 18 to 60 years) with MDD diagnosed by DSM-5 criteria, with Hamilton Depression Rating scale (HAM-D) score ≥ 20 were included in the study. Patients were given bupropion sustained release (SR) in the doses of 150 mg once daily. All patients were followed up for 12 weeks.

RESULTS

HAM-D score at the start of the treatment was 25.57 ± 1.85 which significantly reduced to 10.8 ± 4.24 at 12 weeks of treatment. The serum BDNF level increased significantly (p < 0.05) from 2.42 ± 0.19 ng/ml to 2.97 ± 0.10 ng/ml and the levels of serum TNF-α reduced significantly (p < 0.05) from 4.45 ± 0.95 pg/ml to 2.11 ± 0.84 pg/ml at 12 weeks of treatment, in responders to treatment.

CONCLUSION

The results of our study suggest that bupropion SR monotherapy is effective and well tolerated in MDD patients with moderate to severe depression, and its therapeutic efficacy is accompanied by an increase in serum BDNF levels and a decrease in serum TNF-α levels.

The anti-inflammatory role of SSRI and SNRI in the treatment of depression: a review of human and rodent research studies

RATIONALE

Depression has the topmost prevalence of all psychiatric diseases. It is characterized by a high recurrence rate, disability, and numerous and mostly unclear pathogenic mechanisms. Besides the monoamine or the neurotrophic hypothesis of depression, the inflammatory mechanism has begun to be supported by more and more evidence. At the same time, the current knowledge about the standard treatment of choice, the selective serotonin reuptake inhibitors (SSRIs) and serotonin and noradrenaline reuptake inhibitors (SNRIs), is expanding rapidly, adding more features to the initial ones.

OBJECTIVES

This review summarizes the in vivo anti-inflammatory effects of SSRIs and SNRIs in the treatment of depression and outlines the particular mechanisms of these effects for each drug separately. In addition, we provide an overview of the inflammation-related theory of depression and the underlying mechanisms.

RESULTS

SSRIs and SNRIs decrease the neuroinflammation through multiple mechanisms including the reduction of blood or tissue cytokines or regulating complex inflammatory pathways: nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), inflammasomes, Toll-like receptor 4 (TLR4), peroxisome proliferator-activated receptor gamma (PPARγ). Also, SSRIs and SNRIs show these effects in association with an antidepressant action.

CONCLUSIONS

SSRIs and SNRIs have an anti-neuroinflammatory role which might contribute the antidepressant effect.

The Antidiabetic Metformin as an Adjunct to Antidepressants in Patients with Major Depressive Disorder: A Proof-of-Concept, Randomized, Double-Blind, Placebo-Controlled Trial

Metformin (MET) has been reported to have antidepressant effects in animal models and in diabetic patients with depression, owing to its anti-inflammatory, antioxidant, and neuroprotective activity. Accordingly, we proposed that MET would show antidepressant effects in patients with major depressive disorder (MDD) without other comorbidities. In this double-blind placebo-controlled study, 80 adult outpatients with MDD (DSM-IV criteria) and a Hamilton Depression Rating Scale (HAM-D) score >18 were randomized to receive fluoxetine 20 mg once daily plus placebo (n = 40) or fluoxetine 20 mg once daily plus MET 1000 mg once daily for 12 weeks. Patients were assessed by HAM-D score (weeks 0, 4, 8, and 12). The serum levels of TNF-α, IL-1β, IL-6, IGF-1, MDA, CRP, BDNF, and serotonin were measured before and after therapy. Mixed-effects model repeated-measures analysis of covariance was used to compare the HAM-D scores and the biological markers between the two groups. After 4, 8 and 12 weeks, patients in the MET group showed a statistically significant decline in HAM-D score relative to the placebo group (least squares mean difference [LSMD] -2.347, p = 0.000, LSMD -3.369, p = 0.000, and LSMD -3.454, p = 0.000, respectively). Response and remission rates were significantly higher in the MET group (89% and 81%, respectively) than in the placebo group (59% and 46%, respectively). Moreover, the MET group was superior in conserving the measured biological markers compared with the placebo group. Our findings suggest MET as a promising, effective, and safe short-term adjunctive approach in nondiabetic MDD patients. Trial registration ID: NCT04088448.

Differences in cytokines between patients with generalised anxiety disorder and panic disorder

OBJECTIVE

The purpose of this study was to evaluate the differences among panic disorder (PD), generalised anxiety disorder (GAD) and controls in inflammatory cytokines. We also analysed the correlation between inflammatory cytokines and response to escitalopram in PD and GAD patients.

METHODS

Eighty-six patients with PD, 86 patients with GAD and 86 healthy controls were recruited for this study. All participants were, respectively, assessed for severity of anxiety and panic symptoms using the Hamilton Anxiety Rating Scale (HAMA) and the Panic Disorder Severity Scale (PDSS); all patients in the study were also assessed after 4 weeks of treatment. The serum levels of cytokines were measured using a flow fluorescence microsphere assay.

RESULTS

Both PD and GAD patients had higher serum levels of interleukin 6 (IL-6) than controls, and patients with PD showed significantly higher IL-6 than GAD patients. Significant positive correlations were found between the IFN-γ levels and the severity of anxiety in GAD patients. Higher level of IL-6 was associated with better response to escitalopram treatment in PD patients. However, the baseline levels of cytokines were not associated with treatment responses in GAD patients.

CONCLUSION

The present findings suggest that patients with PD may have higher levels of IL-6 than GAD, and higher baseline levels of IL-6 may be a better response to escitalopram in the treatment of PD.

Gene-disease association study of tumor necrosis factor-α G-308A gene polymorphism with risk of major depressive disorder: A systematic review and meta-analysis

INTRODUCTION

The single nucleotide polymorphism (SNP) of the tumor necrosis factor-α (TNF-α) G-308A gene is the most studied regarding susceptibility to major depressive disorder (MDD). However, results have been controversial perhaps due to the heterogeneous genetic backgrounds influenced by race as well as subtypes of depression.

METHODS AND MATERIALS

A systematic MEDLINE search was performed to retrieve all published studies that identified the connection between the TNF-α G-308A gene polymorphism and the risk of MDD.

RESULTS

There was no statistical difference between the allele frequencies or genotypes of TNF-α G-308A gene and the depressive patients or healthy subjects in the five models tested. Further, subgroup analyses showed that the TNF-α G-308A gene polymorphism also did not confer susceptibility to poststroke, late-life, maternal, or major depression. Publication bias analysis showed p values were more than .05, suggesting that the 9 articles included in the current analysis had no publication bias.

CONCLUSION

Neither the allele frequencies nor genotypes of TNF-α G-308A gene could be served as an independent risk factor of depression.

Inflammatory modulation of fluoxetine use in patients with depression: A systematic review and meta-analysis

There is growing evidence that there is a relationship between major depressive disorder (MDD), also simply known as "depression", and inflammatory processes. Selective serotonin inhibitors, such as fluoxetine, are used as a first-line treatment for depression, and it is hypothesized that its use can reduce levels of proinflammatory cytokines. The aim of this systematic review and meta-analysis is to enable a better understanding of how treatment with the antidepressant fluoxetine modulates inflammation, and the roles of the main cytokines in this process. Risk of bias (RoB) in the included studies was assessed using the Cochrane Risk of Bias Assessment tool for Non-randomized studies (RoBANS). In the meta-analysis, standardized mean difference (SMD) was used as a summary statistic and grouped statistics using the generic inverse variation method in RevMan 5 with random effects model. Heterogeneous changes in cytokine levels were also evaluated from the SMD forest plot of individual studies. After analysis, we observed that fluoxetine was able to decrease TNF-α levels (SMD ± 0.90, 95% CI = 0.16, 1.165, Z ± 2.40, p = 0.02), but not change IL-6 levels (SMD ± 0.37, 95% CI = 0.21, 0.95, Z ± 1.25, p = 0.21).Fluoxetine acts by modulating neuroimmunology, and not only by acting only on the independent restoration of neurotransmission and neuroinflammation pathways.

Melatonergic agonist regulates circadian clock genes and peripheral inflammatory and neuroplasticity markers in patients with depression and anxiety

OBJECTIVE

Circadian dysfunction is a core manifestation and a risk factor for psychiatric disorders. Ramelteon (RMT), a melatonin receptor agonist, has been shown to induce sleep phase shifts and has been used to normalize sleep onset time. RMT has been used in sleep disorders, depression and anxiety. In this study, we aimed to investigate the effects of RMT in regulating gene expression profiles of the circadian clock and peripheral markers of inflammation and neuroplasticity.

METHODS

Sixteen patients with a diagnosis of primary insomnia comorbid with depression and anxiety and ten healthy controls were recruited in an 8-week open-label trial. The patients with primary insomnia received RMT 8 mg/day. The morning expression profiles of 15 core clock genes from peripheral blood mononuclear cells (PBMCs), urine and plasma levels of melatonin and its metabolite levels, and plasma inflammatory markers and neurotrophin levels were evaluated at baseline, 4th and 8th week of RMT treatment.

RESULTS

RMT treatment was associated with significant clinical improvement in depression scores at 8th week (Hamilton depression rating scale scores (Mean ± SEM) from 21.5 ± 2.44 to 14.31 ± 2.25, p ≤ 0.05). The overall poor sleep quality (Pittsburgh sleep quality index) of the patient group significantly improved (p ≤ 0.05) following RMT treatment. The mRNA level analysis showed a significant association between RMT treatment and alterations of the nine core circadian genes (CLOCK, PER1, PER2, CRY1, CRY2, NR1D1, NR1D2, DEC1 and TIMELESS) in the patient group when compared with the control group (p ≤ 0.05). Compared with the controls, the patient group had a decrease in neurotrophins (brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor and beta-nerve growth factor; p ≤ 0.05) but an increase in pro-inflammatory cytokine levels (interleukin-6, interleukin-1b, tumour necrosis factor-alpha and interferon gamma; p ≤ 0.05); RMT treatment normalized the levels of neurotrophins and cytokine levels.

CONCLUSION

RMT treatment is able to restore phase-shifted melatonin markers, normalized the altered expression of the circadian genes, the levels of inflammatory cytokines and neurotrophins in patients with insomnia comorbid anxiety and depression.

Reduced serum BDNF levels are associated with the increased risk for developing MDD: a case-control study with or without antidepressant therapy

Objective

We do not have any consistent markers for major depressive disorder (MDD) though various biological factors are involved in the pathophysiology. We aimed to evaluate the serum brain-derived neurotrophic factor (BDNF) levels in MDD patients with or without antidepressant therapy compared to healthy controls (HCs).

Results

We assessed serum BDNF levels among three groups: drug-naïve MDD patients (n = 41), drug-treated MDD patients (n = 44), and age-and sex-matched HCs (n = 82). Serum BDNF levels were measured by enzyme-linked immunosorbent assay (ELISA) kit. Serum levels of BDNF were detected significantly lower in drug-naïve MDD patients compared to HCs. No significant alterations of serum BDNF levels between drug-treated patients and HCs were identified. Significant negative correlations between serum BDNF levels and Hamilton depression rating (Ham-D) scores were observed in both drug-naïve and drug-treated MDD patients. Receiver operating characteristic (ROC) analysis showed good diagnostic value for serum BDNF levels in drug-naïve MDD patients with the area under the curve at 0.821. The present study suggests that low serum BDNF levels may be involved in the pathophysiology of MDD. The reduced serum BDNF levels might be used as an early risk assessment marker for major depression.

Peripheral cytokine levels and response to antidepressant treatment in depression: a systematic review and meta-analysis

Predicting antidepressant treatment response has been a clinical challenge for major depressive disorder (MDD). The inflammation hypothesis of depression suggests that cytokines play a key role in the pathophysiology of MDD and alterations in peripheral cytokine levels are associated with antidepressant treatment outcome. Present meta-analysis aimed to examine the association between baseline peripheral cytokine levels and the response to antidepressant treatment and to evaluate whether changes of cytokine levels were associated with the response to antidepressant treatment in patients with MDD. Human-based studies published in any language in peer-reviewed journals were systematically searched from the PubMed, Embase and Web of Science databases, from inception up to October 2018. The search terms included cytokine, depressive disorder and antidepressant and their synonyms. Case-control or case-case studies reporting on levels of IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, CRP, TNF-α, IFN-γ, GM-CSF, MIP-1α, and Eotaxin-1 in patients with MDD based on validated depression scales both before and after antidepressant treatment were included. Of 7408 identified records, 44 studies met inclusion. Standardized mean differences in each cytokine were evaluated, and random-effects meta-analyses were performed. MDD patients who responded to antidepressant treatment had lower baseline IL-8 levels than the nonresponders (Hedge's g = -0.28; 95%CI, -0.43 to -0.13; P = 0.0003; FDR = 0.004). Antidepressant treatment significantly decreased levels of TNF-α (Hedge's g = 0.60; 95%CI, 0.26-0.94; P = 0.0006; FDR = 0.004) only in responders, and responders showed significantly more decreased TNF-α levels compared with nonresponders (P = 0.046). These findings suggested that alterations in peripheral cytokine levels were associated with antidepressant treatment outcomes in MDD. Further investigations are warranted to elucidate sources of heterogeneity and examine the potentiality of using inflammatory cytokines as novel predictive markers for the pharmacological treatment of MDD.

Agomelatine prevents indomethacin-induced gastric ulcer in rats

BACKGROUND

Gastric ulcer is a very common gastrointestinal disease that may be dangerous and even may lead to death. The current study was conducted to detect the prophylactic effects of agomelatine on indomethacin-induced gastric ulcer.

METHODS

In this study, a total of 5 groups were created as the sham, ulcer, omeprazole, agomelatine 1 mg/kg and agomelatine 5 mg/kg groups. The effects of agomelatine on indomethacin-induced gastric injury were investigated. Total antioxidant and oxidant levels; the oxidant parameters like oxidative stress index and the inflammation markers such as tumor necrosis factor-α, interleukin-1β, interleukin-6 and interleukin-10 levels in stomach tissue were determined by ELISA. In addition, the gastric mucosal injury occurred in stomach wall was examined with histopathological methods.

RESULTS

While the levels of the inflammatory markers, total oxidant status and oxidative stress index increased at an obvious level especially in the indomethacin group, the total antioxidant status levels decreased. It was observed that these parameters were improved at a significant level in agomelatine 1 mg/kg and agomelatine 5 mg/kg groups when compared to ulcer group; and the results were similar to omeprazole group. It was also observed that our histopathological findings were consistent with all our other results.

CONCLUSIONS

The results of this study showed that agomelatine usage in indomethacin-induced gastric ulcer model provides beneficial results.

The Diagnostic Value of the Combination of Serum Brain-Derived Neurotrophic Factor and Insulin-Like Growth Factor-1 for Major Depressive Disorder Diagnosis and Treatment Efficacy

BACKGROUND

Last decades of psychiatric investigations have been marked by a search for biological markers that can clarify etiology and pathogenesis, confirm the diagnosis, screen individuals at risk, define the severity, and predict the course of mental disorders. In our study, we aimed to evaluate if BDNF and IGF-1 serum concentrations separately and in combination might be used as biomarkers for major depressive disorder (MDD) diagnosis and treatment efficacy and to evaluate the relationships among those proteins and clinical parameters of MDD.

METHODS

Forty-one MDD patients (according to DSM-5) and 32 healthy controls (HC) were included in this study. BDNF and IGF-1 serum concentrations, psychopathological (MADRS, CGI) and neuropsychological parameters (PDQ-5, RAVLT, TMT-B, DSST), functioning according to Sheehan Disability Scale were analyzed in all subjects at admission and 30 MDD patients after 8 weeks of vortioxetine treatment. Correlational analyses were performed to explore relationships between BDNF and IGF-1 and clinical characteristics. AUC-ROCs were calculated to determine if the value of serum BDNF and IGF-1 levels could serve for MDD diagnosis.

RESULTS

MDD patients had significantly lower serum BDNF (727.6 ± 87.9 pg/ml vs. 853.0 ± 93.9 pg/ml) and higher serum IGF-1 levels (289.15 ± 125.3 ng/ml vs. 170.2 ± 58.2 ng/ml) compared to HC. Significant correlations were obtained between BDNF levels and MDD status, depressive episode (DE) severity, precipitating factors, executive functions disruption (TMT-B, RAVLT immediate recall scores) and all subdomains of functioning. As for IGF-1, correlations were found between IGF-1 level and MDD status, DE severity, number and duration of DE, parameters of subjective and objective cognitive functioning (PDQ-5, RAVLT, TMT-B, DSST scores), and all subdomains of functioning. The associations between IGF-1 concentrations and cognitive tests' performance were stronger than those of BDNF. Separately both BDNF and IGF-1 demonstrated good discriminating ability for MDD diagnosis with AUC of 0.840 and 0.824, respectively. However, the combination of those neurotrophins had excellent diagnostic power to discriminate MDD patients from HC, providing an AUC of 0.916. Vortioxetine treatment significantly increased BDNF and attenuated IGF-1 serum concentrations, improved all psychopathological and neuropsychological parameters and functioning.

CONCLUSIONS

The combination of IGF-1 and BDNF might be considered as a diagnostic combination for MDD.

Tumor Necrosis Factor-α Variations in Patients With Major Depressive Disorder Before and After Antidepressant Treatment

Tumor necrosis factor-α (TNF-α) had been identified as a key pro-inflammatory cytokine in the pathophysiology of major depressive disorder (MDD) and the mechanism of antidepressant treatment. The primary aim of the present study was to examine the serum TNF-α levels in Chinese inpatients with MDD during the acute phase and to explore the changes in TNF-α levels after effective clinical treatment. Fifty-seven consecutive inpatients with MDD and 30 healthy controls were recruited. The serum TNF-α levels were detected using ELISA. Symptoms of depression were evaluated using the 24-item Hamilton Rating Scale for Depression (HAM-D-24). TNF-α levels and HAM-D-24 scores were assessed at baseline and after 2 and 12 weeks of follow-up. The serum TNF-α levels were higher in the MDD group than in the control group. After 2 and 12 weeks of antidepressant treatment, there were significant improvements in the patients' symptoms and significant decreases in the TNF-α levels. The baseline TNF-α levels significantly correlated with the decreased HAM-D-24 scores, particularly for the depressive symptoms of anxiety/somatization and weight loss. The present findings indicate that depression is accompanied by activation of TNF-α, which also has a predictive value for the antidepressant treatment response in patients with MDD.

Pharmacological Manipulation of the Circadian Clock: A Possible Approach to the Management of Bipolar Disorder

Bipolar disorder (BD) is a mood disorder with genetic and neurobiological underpinnings, characterized primarily by recurrent episodes of mania and depression, with notable disruptions in rhythmic behaviors such as sleep, energy, appetite and attention. The chronobiological links to BD are further supported by the effectiveness of various treatment modalities such as bright light, circadian phase advance, and mood-stabilizing drugs such as lithium that have effects on the circadian clock. Over the past 30 years, the neurobiology of the circadian clock has been exquisitely described and there now exists a detailed knowledge of key signaling pathways, neurotransmitters and signaling mechanisms that regulate various dimensions of circadian clock function. With this new wealth of information, it is becoming increasingly plausible that new drugs for BD could be made by targeting molecular elements of the circadian clock. However, circadian rhythms are multidimensional and complex, involving unique, time-dependent factors that are not typically considered in drug development. We review the organization of the circadian clock in the central nervous system and briefly summarize data implicating the circadian clock in BD. We then consider some of the unique aspects of the circadian clock as a drug target in BD, discuss key methodological considerations and evaluate some of the candidate clock pathways and systems that could serve as potential targets for novel mood stabilizers. We expect this work will serve as a roadmap to facilitate the development of compounds acting on the circadian clock for the treatment of BD.

Effects of SSRIs on peripheral inflammatory markers in patients with major depressive disorder: A systematic review and meta-analysis

INTRODUCTION

Peripheral levels of inflammatory markers are elevated in major depressive disorder (MDD). Selective serotonin reuptake inhibitors (SSRIs) affect levels of inflammatory markers in patients with MDD, but studies have reported inconsistent findings. This systematic review and meta-analysis aims to investigate the effects of SSRI treatment on peripheral levels of a range of inflammatory markers in MDD patients.

METHODS

Systematic literature search (Pubmed, Web of Science, Embase, Cochrane) for studies published before November 2018. Studies were included if they used SSRI monotherapy and peripheral levels of interleukin (IL)-1β, IL-2, IL-4, IL-6, IL-10, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ were measured before and after treatment in patients with MDD. Meta-analysis was conducted using Comprehensive Meta-analysis (version 2). Effect sizes were calculated using bias-corrected standardized mean difference (Hedges' g) between pre- and post-treatment. Sub-group analyses, meta-regression and publication bias estimates were undertaken; sensitivity analyses were performed using different estimated pre- and post-treatment correlations and after removing poor quality studies.

RESULTS

Twenty two eligible studies including 827 MDD patients were included in the meta-analysis: fifteen studies for IL-6; eleven for TNF-α; eight for IL-10; seven for IL-1β; six for IL-4; five for IL-2; and four for IFN-γ. The pooled effect estimate indicates SSRI treatment decreased levels of pro-inflammatory markers IL-6 (Hedges' g, -0.418; 95%CI, -0.663 to -0.174; I² = 89.412), TNF-α (Hedges' g, -0.554; 95%CI, -0.990 to -0.118; I² = 95.438) and IL-1β (Hedges' g = -0.574; 95%CI, -1.014 to -0.135; I² = 91.622), and anti-inflammatory marker IL-10 (Hedges' g = -0.615; 95%CI, -0.989 to -0.242; I² = 90.406). There were no significant treatment effects on levels of IL-2, IL-4, or IFN-γ. There was a high level of heterogeneity between studies. Sensitivity analyses indicated the robustness of the primary analyses.

CONCLUSIONS

The current review and meta-analysis indicates moderate immunomodulating effects of SSRI treatment for MDD, which suggests SSRIs may owe some of their therapeutic effect to their anti-inflammatory properties. High heterogeneity across studies may limit interpretation of the findings and larger randomized clinical trials are warranted.

Selective serotonin reuptake inhibitor effects on neural biomarkers of perinatal depression

The effect of perinatal selective serotonin reuptake inhibitors (SSRIs) on brain-derived neurotrophic factor (BDNF) and S100 calcium binding protein B (S100B) has not been investigated. Using a cohort of 86 pregnant women, we found that SSRIs significantly increase BDNF levels in late pregnancy and that S100B, but not BDNF, is associated with maternal depression in SSRI-treated women only. This shows that serum S100B could be a unique biomarker to determine efficacy of SSRIs during gestation.

Association Study Between Serotonin Transporter Gene and Fluoxetine Response in Mexican Patients With Major Depressive Disorder

OBJECTIVE

Pharmacogenetic studies have identified genetic variants associated with fluoxetine response in patients with major depression disorder (MDD). The serotonin transporter gene is the principal site of action of selective serotonin reuptake inhibitors. Previous studies analyzing SLC6A4 gene variants are inconsistent and differ among populations. The aim of the present study was to analyze the association between 5-HTTLPR/rs24531 triallelic polymorphism and fluoxetine response in Mexican patients with MDD.

METHODS

We analyzed a sample of 150 patients with MDD. Fluoxetine response was assessed according to a reduction in the Hamilton Depression Rating Scale and Montgomery Depression Rating Scale scores of 50% or more at 8 weeks from baseline. In addition, we analyzed the genotype and allele distribution between responder and nonresponder patients in a subgroup of very severe depression patients.

RESULTS

We did not find association between fluoxetine responders and 5-HTTLPR/rs25531 variants (P = 0.0637). However, in the analysis of severe depression at baseline (Hamilton Depression Rating Scale ≥ 25), we observed a high frequency of low activity alleles (S/LG) in nonresponders patients (P = 0.0102).

CONCLUSIONS

Our findings showed an association between low activity alleles of SLC6A4 gene and fluoxetine nonresponse in patients with severe depression.

Changes in neuroplasticity following early-life social adversities: the possible role of brain-derived neurotrophic factor

Social adversities experienced in childhood can have a profound impact on the developing brain, leading to the emergence of psychopathologies in adulthood. Despite the burden this places on both the individual and society, the neurobiological aspects mediating this transition remain unclear. Recent advances in preclinical and clinical research have begun examining neuroplasticity-the nervous system's ability to form adaptive changes in response to new experience-in the context of early-life vulnerability to social adversities and plasticity-related alterations following such traumatic events. A key mediator of plasticity-related molecular processes is the brain-derived neurotrophic factor (BDNF), which has also been implicated in various psychiatric disorders related to childhood social adversities. Preclinical and clinical data suggest early-life social adversities (ELSA) might be associated with accelerated maturation of social network circuitry, a possible ontogenic adaptation to the adverse environment. Neural plasticity decreases by adulthood, lessening the efficacy of treatment in ELSA-related psychiatric disorders. However, literature data suggest that by increasing BDNF/TrkB signalling through antidepressant treatment a juvenile-like plasticity state can be induced, which allows for reorganization of the social circuitry when guided by psychotherapy and surrounded by a safe and positive environment.

MicroRNA-27a participates in the pathological process of depression in rats by regulating VEGFA

The present study aimed to determine the expression of vascular endothelial growth factor A (VEGFA) and microRNA (miRNA/miR)-27a in hippocampal tissues, and serum from a depression model of rats. In addition, the present study aimed to understand the mechanism of regulation of miR-27a in depression. A total of 40 male rats were selected, and divided into the control and depression model groups. The rats in the model group were subjected to 14 types of stimulations to model depression. By determining the body weight, syrup consumption rate and open field test score, the extent of depression in the rats was evaluated. Quantitative-polymerase chain reaction was used to determine the expression of VEGFA mRNA and miR-27a in hippocampal tissues, and serum. ELISA was used to measure the content of VEGFA protein in serum, while western blotting was employed to determine the expression of VEGFA protein in hippocampal tissues. A dual luciferase assay was carried out to identify the interactions between VEGFA mRNA and miR-27a. The rats in the depression model group showed depression symptoms and the depression model was successfully constructed. Rats with depression had lower VEGFA mRNA and protein expression in the hippocampus, and peripheral blood compared with the control group. Rats in the depression model group had reduced levels of miR-27a in the hippocampus and peripheral blood, which may be associated with the levels of VEGFA. miR-27a was able to bind with the 3′-untranslated region of VEGFA mRNA to regulate its expression. The present study demonstrated that miR-27a expression in hippocampal tissues and blood from rats with depression is upregulated, while the expression of VEGFA mRNA and protein is downregulated. miR-27a may participate in the pathological process of depression in rats by regulating VEGFA.

Melatonin Promotes Brain-Derived Neurotrophic Factor (BDNF) Expression and Anti-Apoptotic Effects in Neonatal Hemolytic Hyperbilirubinemia via a Phospholipase (PLC)-Mediated Mechanism

BACKGROUND Melatonin therapy shows positive effects on neuroprotective factor brain-derived neurotrophic factor (BDNF) expression and neuronal apoptosis in neonatal hemolytic hyperbilirubinemia. We hypothesized that melatonin promotes BDNF expression and anti-apoptotic effects in neonatal hemolytic hyperbilirubinemia through a phospholipase (PLC)-mediated mechanism. MATERIAL AND METHODS A phenylhydrazine hydrochloride (PHZ)-induced neonatal hemolytic hyperbilirubinemia model was constructed in neonatal rats. Four experimental groups - a control group (n=30), a PHZ group (n=30), a PHZ + melatonin group (n=30), and a PHZ + melatonin+U73122 (a PLC inhibitor) group (n=30) - were constructed. Trunk blood was assayed for serum hemoglobin, hematocrit, total and direct bilirubin, BDNF, S100B, and tau protein levels. Brain tissue levels of neuronal apoptosis, BDNF expression, PLC activity, IP3 content, phospho- and total Ca2+/calmodulin-dependent protein kinase type IV (CaMKIV) expression, and phospho- and total cAMP response element binding protein (CREB) expression were also assayed. RESULTS PHZ-induced hemolytic hyperbilirubinemia was validated by significantly decreased serum hemoglobin and hematocrit as well as significantly increased total and direct serum bilirubin (p<0.05). Neonatal bilirubin-induced neurotoxicity was validated by significantly decreased serum BDNF, brain BDNF, and serum S100B, along with significantly increased serum tau protein (p<0.05). PHZ-induced hemolytic hyperbilirubinemia significantly decreased serum BDNF, brain BDNF, and PLC/IP3/Ca2+ pathway activation while increasing neuronal apoptosis levels (p<0.05), all of which were partially rescued by melatonin therapy (p<0.05). Pre-treatment with the PLC inhibitor U73122 largely abolished the positive effects of melatonin on PLC/IP3/Ca2+ pathway activation, downstream BDNF levels, and neuronal apoptosis (p<0.05). CONCLUSIONS Promotion of BDNF expression and anti-apoptotic effects in neonatal hemolytic hyperbilirubinemia by melatonin largely operates via a PLC-mediated mechanism.