IL-1β, IL-6, IL-8, IL-10, IFN-γ, TNF-α and its relationship with lipid parameters in patients with major depression

Activation of the interleukin-23/Th17 axis in major depression: a systematic review and meta-analysis

The interleukin-23/Th17 axis is a promising modifiable target for depression. However, its association with depression has not been systematically evaluated. We systematically searched four databases (EMBASE, Web of Science, Pubmed and PsycINFO) for studies comparing patients with major depression and healthy controls for plasma/serum levels of Th17 cells and their canonical cytokines (interleukin-17A [IL-17A], IL-22, granulocyte macrophage colony stimulating factor [GM-CSF]). We also compared counts of Th1, Th2 and Th9 cells between depressed/non-depressed patients and their respective canonical cytokines. We performed random-effects meta-analysis of the standardised mean difference (SMD) in immune measures between groups. Risk of bias was assessed using the Newcastle-Ottawa scale. Of 3154 studies screened, 36 studies were included in meta-analysis. Patients with depression had elevated IL-17A compared to controls (SMD = 0.80 [95% CI 0.03 to 1.58], p = 0.042), an association moderated by antidepressant use (Z = 2.12, p = 0.034). Patients with depression had elevated GM-CSF (SMD = 0.54 [95% CI 0.16 to 0.91], p = 0.0047), and a trend towards higher Th17 counts (SMD = 0.44 [- 0.01 to 0.88], p = 0.052). Whilst the Th2-associated cytokine IL-5 was elevated in depression (SMD = 0.36 [95% CI 0.05 to 0.66], p = 0.02), Th2 cell counts (p = 0.97), Th1 cell counts (p = 0.17) and interferon-γ (p = 0.22) were not. Data for Th9 cells, IL-9 and IL-22 were insufficient for meta-analysis. Respectively, 22, 25 and 5 studies were good, fair and poor in quality. Patients with major depression show peripheral over-activation of the IL-23/Th17 axis. Future interventional studies should test whether this is a modifiable target for depression.

Associations between insomnia symptoms and inflammatory cytokines in adolescents with first-episode and recurrent major depressive disorder

BACKGROUND

Insomnia symptoms are often associated with increased levels of inflammatory biomarkers. However, such associations have not been adequately explored in adolescents with major depressive disorder (MDD). This study aimed to examine the associations between insomnia symptoms with inflammatory cytokines in adolescents with first-episode and recurrent MDD.

METHODS

From January to December 2021, this study included 164 adolescents with MDD and 76 healthy controls (HCs). The Center for Epidemiological Studies Depression Scale (CES-D) and the Insomnia Severity Index Scale (ISI) were used to assess depressive and insomnia symptoms, respectively. Also, plasma levels of interleukin (IL)-1β, IL-6, IL-8, IL-10, IL-17 A and tumor necrosis factor-α (TNF-α) were measured.

RESULTS

The prevalence of mild, moderate and severe insomnia in adolescents with MDD was 40.24 %, 36.59 % and 6.71 %, respectively. The patients had higher levels of IL-1β, IL-6 and TNF-α than HCs (all p < 0.05). ISI score was positively correlated with CES-D score and levels of IL-1β, IL-6 and TNF-α in first-episode patients but not in recurrent patients. A further multivariate stepwise linear regression analysis showed that ISI score was independently associated with CES-D score (beta = 0.523, t = 5.833, p < 0.001) and TNF-α levels (beta = 0.254, t = 2.832, p = 0.006).

LIMITATIONS

The cross-sectional design leads to failure to make causal inferences.

CONCLUSION

Insomnia symptoms are common in adolescents with MDD and associated with elevated levels of inflammatory cytokines in first-episode patients. The findings suggest that inflammatory cytokines may relate to the pathogenesis of insomnia symptoms in adolescents with MDD, but further longitudinal studies are needed to explore the causal association between insomnia symptoms and inflammatory cytokines in MDD.

The hypothalamic steroidogenic pathway mediates susceptibility to inflammation-evoked depression in female mice

BACKGROUND

Depression is two-to-three times more frequent among women. The hypothalamus, a sexually dimorphic area, has been implicated in the pathophysiology of depression. Neuroinflammation-induced hypothalamic dysfunction underlies behaviors associated with depression. The lipopolysaccharide (LPS)-induced mouse model of depression has been well-validated in numerous laboratories, including our own, and is widely used to investigate the relationship between neuroinflammation and depression. However, the sex-specific differences in metabolic alterations underlying depression-associated hypothalamic neuroinflammation remain unknown.

METHODS

Here, we employed the LPS-induced mouse model of depression to investigate hypothalamic metabolic changes in both male and female mice using a metabolomics approach. Through bioinformatics analysis, we confirmed the molecular pathways and biological processes associated with the identified metabolites. Furthermore, we employed quantitative real-time PCR, enzyme-linked immunosorbent assay, western blotting, and pharmacological interventions to further elucidate the underlying mechanisms.

RESULTS

A total of 124 and 61 differential metabolites (DMs) were detected in male and female mice with depressive-like behavior, respectively, compared to their respective sex-matched control groups. Moreover, a comparison between female and male model mice identified 37 DMs. We capitalized on biochemical clustering and functional enrichment analyses to define the major metabolic changes in these DMs. More than 55% of the DMs clustered into lipids and lipid-like molecules, and an imbalance in lipids metabolism was presented in the hypothalamus. Furthermore, steroidogenic pathway was confirmed as a potential sex-specific pathway in the hypothalamus of female mice with depression. Pregnenolone, an upstream component of the steroid hormone biosynthesis pathway, was downregulated in female mice with depressive-like phenotypes but not in males and had considerable relevance to depressive-like behaviors in females. Moreover, exogenous pregnenolone infusion reversed depressive-like behaviors in female mice with depression. The 5α-reductase type I (SRD5A1), a steroidogenic hub enzyme involved in pregnenolone metabolism, was increased in the hypothalamus of female mice with depression. Its inhibition increased hypothalamic pregnenolone levels and ameliorated depressive-like behaviors in female mice with depression.

CONCLUSIONS

Our study findings demonstrate a marked sexual dimorphism at the metabolic level in depression, particularly in hypothalamic steroidogenic metabolism, identifying a potential sex-specific pathway in female mice with depressive-like behaviors.

Association of non-HDL-C and depression: a cross-sectional analysis of the NHANES data

Objectives

Non-high-density lipoprotein cholesterol (non-HDL-C) has attracted attention because it is associated with a variety of diseases and is easy to measure. However, the relationship between non-HDL-C and depression is still unclear. Our aim was to assess the relationship between non-HDL-C and depression using the cross-sectional NHANES survey from 2005 to 2018.

Methods

We examined the association between non-HDL-C and depression using weighted multivariable logistic regression models and subgroup analysis. Sensitivity analysis demonstrated the robustness of the results.

Results

There were 42,143 participants in this study and 8.6% had depression (weighted 7.53%). Non-HDL-C was higher in participants with depression compared to those without depression (weighted mean 3.64 vs. 3.73, p < 0.01). There was a positive association between non-HDL-C and depression with a 95% OR of 1.22 adjusted for multifactorial (95% CI,1.03-1.45). In subgroup analyses, non-HDL-C was positively associated with depression in men (OR, 1.31; 95% CI, 1.01-1.70), normal BMI (OR: 0.93; 95% CI: 0.66-1.32) and in participants without hypertension (OR, 1.29; 95% CI, 1.01-1.66).

Conclusion

Non-HDL-C positively correlated with depression, and further research may be better for clinical service.

Effect of Apremilast on LPS-induced immunomodulation and inflammation via activation of Nrf2/HO-1 pathways in rat lungs

Lipopolysaccharides (LPS), the lipid component of gram-negative bacterial cell wall, is recognized as the key factor in acute lung inflammation and is found to exhibit severe immunologic reactions. Phosphodiesterase-4 (PDE-4) inhibitor: "apremilast (AP)" is an immune suppressant and anti-inflammatory drug which introduced to treat psoriatic arthritis. The contemporary experiment designed to study the protective influences of AP against LPS induced lung injury in rodents. Twenty-four (24) male experimental Wistar rats selected, acclimatized, and administered with normal saline, LPS, or AP + LPS respectively from 1 to 4 groups. The lung tissues were evaluated for biochemical parameters (MPO), Enzyme Linked Immunosorbent Assay (ELISA), flowcytometry assay, gene expressions, proteins expression and histopathological examination. AP ameliorates the lung injuries by attenuating immunomodulation and inflammation. LPS exposure upregulated IL-6, TNF-α, and MPO while downregulating IL-4 which were restored in AP pretreated rats. The changes in immunomodulation markers by LPS were reduced by AP treatment. Furthermore, results from the qPCR analysis represented an upregulation in IL-1β, MPO, TNF-α, and p38 whereas downregulated in IL-10 and p53 gene expressions in disease control animals while AP pretreated rats exhibited significant reversal in these expressions. Western blot analysis suggested an upregulation of MCP-1, and NOS-2, whereas HO-1, and Nrf-2 expression were suppressed in LPS exposed animals, while pretreatment with AP showed down regulation in the expression MCP-1, NOS-2, and upregulation of HO-1, and Nrf-2 expression of the mentioned intracellular proteins. Histological studies further affirmed the toxic influences of LPS on the pulmonary tissues. It is concluded that, LPS exposure causes pulmonary toxicities via up regulation of oxidative stress, inflammatory cytokines and stimulation of IL-1β, MPO, TNF-α, p38, MCP-1, and NOS-2 while downregulation of IL-4, IL-10, p53, HO-1, and Nrf-2 at different expression level. Pretreatment with AP controlled the toxic influences of LPS by modulating these signaling pathways.

Butein Ameliorates Chronic Stress Induced Atherosclerosis via Targeting Anti-inflammatory, Anti-fibrotic and BDNF Pathways

Chronic stress is a major risk factor for various diseases, including cardiovascular diseases (CVDs). Chronic stress enhances the release of pro-inflammatory cytokines like IL-1β, IL-6, and TNF-α, making individuals susceptible to atherosclerosis which is dominant cause for CVDs. In present study, we validated a mouse model of chronic unpredictable stress (CUS), and assessed the characteristic features of atherosclerosis in thoracic aortas of CUS mice. The CUS procedure consisted of exposing groups of mice to random stressors daily for 10-weeks. The stress response was verified by presence of depressive-like behaviors and increased serum corticosterone in mice which was determined by battery of behavioural tests (SPT, EPMT, NSFT) and ELISA, respectively. Atherosclerosis parameters in CUS mice were evaluated by lipid indices estimation followed by histological assessment of plaque deposition and fibrosis in thoracic aorta. Further, we assessed the efficacy of a polyphenol, i.e. Butein in conferring protection against chronic stress-induced atherosclerosis and the possible mechanism of action. Butein (20mg/kg x 28 days, alternatively, i.p.) was administered to CUS mice after 6-weeks of CUS exposure till the end of the protocol. Butein treatment decreased peripheral IL-1β and enhanced peripheral as well as central BDNF levels. Histological assessment revealed decreased macrophage expression and reduced fibrosis in thoracic aorta of Butein treated mice. Further, treatment with Butein lowered lipid indices in CUS mice. Our findings thus, suggest that 10-weeks of CUS induce characteristic features of atherosclerosis in mice and Butein can offer protection in CUS-induced atherosclerosis through multiple mechanisms including anti-inflammatory, antifibrotic and anti-adipogenic actions.

Resveratrol exerts anxiolytic-like effects through anti-inflammatory and antioxidant activities in rats exposed to chronic social isolation

Emerging evidence has confirmed resveratrol's (RES) antioxidant, anti-inflammatory, and antidepressant effects. The beneficial effects of RES were confirmed for several emotional and cognitive deficits. This research aimed to assess the impacts of RES on behavior and hippocampal levels of anti-inflammatory and pro-inflammatory factors in rats exposed to chronic social isolation (SI) stress, which is known to induce mental disorders such as depressive-like behavior. The animals were treated by RES (20, 40, or 80 mg/kg/intraperitoneally) for 28 days following a 28-day exposure to stress. Behavioral tests, including the forced swim test (FST), open-field test (OFT), tail suspension test (TST), and sucrose preference test (SPT), assessed depressive symptoms. Finally, the animals were sacrificed, and molecular studies (qPCR and ELISA) were performed. Exposure of animals to SI dramatically increased the immobility of animals in TST and FST, enhanced the time spent in the open-field peripheral zone of the OFT, and reduced the sucrose preference rate. In addition, SI increased serum levels of corticosterone and hippocampal content of MDA, whereas it reduced hippocampal SOD and CAT activities. Moreover, SI upregulated the expression of IL-10, IL-18, and IL-1β and downregulated the expression of TGF-β in the hippocampus. RES treatment (40 & 80 mg/kg) significantly improved the behavioral alterations through the modulation of neuroinflammation and oxidative stress. The 20 mg/kg RES dose was inefficient for treating SI-induced depressive-like behavior. These results indicated that RES attenuated depressive-like behavior in prolonged stressed animals. These properties might be associated with RES-mediated improvements in serum corticosterone and hippocampal inflammatory and oxidative stress biomarkers.

Innate lymphoid cells in depression: Current status and perspectives

The recent discovery of innate lymphoid cells (ILCs) has provided new insights into our understanding of the pathogenesis of many disease conditions with immune dysregulation. Type 1 innate lymphoid cells (ILC1s) induce type I immunity and are characterized by the expression of signature cytokine IFN-γ and the master transcription factor T-bet; ILC2s stimulate type II immune responses and are defined by the expression of signature cytokines IL-5 and IL-13, and transcription factors ROR-α and GATA3; ILC3s requires the transcription factor RORγt and produce IL-22 and IL-17. ILCs are largely tissue-resident and are enriched at barrier surfaces of the mammalian body. Increasing evidence shows that inflammation is involved in the pathogenesis of depression. Although few studies have directly investigated the role of ILCs in depression, several studies have examined the levels of cytokines produced by ILCs in depressed subjects. This review summarizes the potential roles of ILCs in depression. A better understanding of the biology of ILCs may lead to the development of new therapeutic strategies for the management of depression.

Use of Sertraline in Hemodialysis Patients

Depression and anxiety are the most common psychiatric disorders in end-stage renal disease (ESRD) patients treated with hemodialysis (HD) and may correlate with lower quality of life and increased mortality. Depression treatment in HD patients is still a challenge both for nephrologists and psychiatrists. The possible treatment of depressive disorders can be pharmacological and non-pharmacological. In our article, we focus on the use of sertraline, the medication which seems to be relatively safe and efficient in the abovementioned population, taking under consideration several limitations regarding the use of other selective serotonin reuptake inhibitors (SSRIs). In our paper, we discuss different aspects of sertraline use, taking into consideration possible benefits and side effects of drug administration like impact on QTc (corrected QT interval) prolongation, intradialytic hypotension (IDH), chronic kidney disease-associated pruritus (CKD-aP), bleeding, sexual functions, inflammation, or fracture risk. Before administering the medication, one should consider benefits and possible side effects, which are particularly significant in the treatment of ESRD patients; this could help to optimize clinical outcomes. Sertraline seems to be safe in the HD population when provided in proper doses. However, we still need more studies in this field since the ones performed so far were usually based on small samples and lacked placebo control.

Higher levels of C-reactive protein in the acute phase of stroke indicate an increased risk for post-stroke depression: A systematic review and meta-analysis

BACKGROUND

Investigations have revealed the association between inflammation and post-stroke depression (PSD). However, whether the C-reactive protein (CRP) level, a biomarker of inflammation, would affect the development of PSD is still controversial.

METHODS

A systematic search of databases was performed for eligible studies. Standardized Mean Difference (SMD) with 95 % Confidence Interval (CI) was used to assess the association between the CRP level in the acute phase of stroke and the risk of PSD.

RESULTS

13 cohort studies that involved 3536 participants were included. Combined results showed that compared with non-PSD patients, the CRP level of PSD patients was significantly higher on admission (SMD = 0.19, 95 % CI: 0.12-0.27). A subgroup analysis by classifying the assessment time of depression showed obvious differences of the CRP levels between the PSD patients who were diagnosed more than 1 month after stroke and the non-PSD (1-3 months: SMD = 0.16, 95 % CI: 0.06-0.25; >3months: SMD = 0.34, 95 % CI: 0.18-0.51).

CONCLUSION

A higher level of CRP in the acute phase of stroke suggests an increased risk for PSD.

A systematic review and meta-analysis of lipid metabolomic signatures of Major Depressive Disorder

The aim of this meta-analysis was to provide a comprehensive synthesis of the evidence examining biomarker signatures in MDD patients including lipids, lipid regulatory proteins (LRP), and polyunsaturated fatty acid (PUFA) as compared to healthy individuals. We performed meta-analyses and meta-regression of the studies comparing lipid, LRP, and PUFA levels between MDD patients and healthy individuals by searching Embase, Ovid Medline, Scopus, PsycINFO, PubMed, and Cochrane databases. Search was performed in these databases up to September 2019 and 29 studies were included. Levels of lipid parameter triglyceride (TG) (SMD 0.55, 95% CI 0.30-0.80, p < 0.0001) were higher while total cholesterol (TC) (SMD = -0.46, 95%CI -0.93 to -0.001, p = 0.04) and very low-density lipoprotein (VLDL) (SMD = -0.46, 95%CI -0.71 to -0.20, p = 0.02) were lower in MDD patients than controls. Subgroup analysis for age showed that the levels of high-density lipoprotein (HDL) were lower in ≥40-year age group (SMD = -0.38, 95%CI -0.70 to -0.06, p = 0.01) and levels of TC was lower in MDD patients in studies from Asian countries (SMD = -0.74, 95%CI -1.37 to -0.10, p = 0.02). TG levels were found to be high all subgroups in MDD patients than controls. A negative association between TC levels and use of lipid lowering medications and a positive association between smoking and LDL levels was found using meta-regression analysis. This study will be useful for physicians when considering the assessment of lipidand LRP profiles in MDD patients to reduce the cardiovascular morbidity and mortality.

Inflammatory markers in depression: A meta-analysis of mean differences and variability in 5,166 patients and 5,083 controls

IMPORTANCE

The magnitude and variability of cytokine alterations in depression are not clear.

OBJECTIVE

To perform an up to date meta-analysis of mean differences of immune markers in depression, and to quantify and test for evidence of heterogeneity in immune markers in depression by conducting a meta-analysis of variability to ascertain whether only a sub-group of patients with depression show evidence of inflammation.

DATA SOURCES

Studies that reported immune marker levels in peripheral blood in patients with depression and matched healthy controls in the MEDLINE database from inception to August 29th 2018 were examined.

STUDY SELECTION

Case-control studies that reported immune marker levels in peripheral blood in patients with depression and healthy controls were selected.

DATA EXTRACTION AND SYNTHESIS

Means and variances (SDs) were extracted for each measure to calculate effect sizes, which were combined using multivariate meta-analysis.

MAIN OUTCOMES AND MEASURES

Hedges g was used to quantify mean differences. Relative variability of immune marker measurements in patients compared with control groups as indexed by the coefficient of variation ratio (CVR).

RESULTS

A total of 107 studies that reported measurements from 5,166 patients with depression and 5,083 controls were included in the analyses. Levels of CRP (g = 0.71; 95%CI: 0.50-0.92; p < 0.0001); IL-3 (g = 0.60; 95%CI: 0.31-0.89; p < 0.0001); IL-6 (g = 0.61; 95%CI: 0.39-0.82; p < 0.0001); IL-12 (g = 1.18; 95%CI: 0.74-1.62; p < 0.0001); IL-18 (g = 1.97; 95%CI: 1.00-2.95; p < 0.0001); sIL-2R (g = 0.71; 95%CI: 0.44-0.98; p < 0.0001); and TNFα (g = 0.54; 95%CI: 0.32-0.76; p < 0.0001) were significantly higher in patients with depression. These findings were robust to a range of potential confounds and moderators. Mean-scaled variability, measured as CVR, was significantly lower in patients with depression for CRP (CVR = 0.85; 95%CI: 0.75-0.98; p = 0.02); IL-12 (CVR = 0.61; 95%CI: 0.46-0.80; p < 0.01); and sIL-2R (CVR = 0.85; 95%CI: 0.73-0.99; p = 0.04), while it was unchanged for IL-3, IL-6, IL-18, and TNF α.

CONCLUSIONS AND RELEVANCE

Depression is confirmed as a pro-inflammatory state. Some of the inflammatory markers elevated in depression, including CRP and IL-12, show reduced variability in patients with depression, therefore supporting greater homogeneity in terms of an inflammatory phenotype in depression. Some inflammatory marker elevations in depression do not appear due to an inflamed sub-group, but rather to a right shift of the immune marker distribution.

Varieties of immunity activities and gut contents in tilapia with seasonal changes

We performed 16S rDNA sequencing of tilapia fecal samples to analyze changes in tilapia gut contents after cultivation of the fish in the presence of sandwich-like floating beds of Chinese medicinal herbs (5 and 10% planting-areas; 5% Polygonum cuspidatum). The interactive effects between water quality and blood and hepatic pro- and anti-inflammatory concentrations were also assessed. Our results showed that the water quality (i.e., NO₃^--N, NO₂^--N, TP removal rates) improved, and the abundance of Chloroflexi and Cyanobacteria increased. The abundance of Bacteroidetes, Verrucomicrobia, Saccharibacteria, and Actinobacteria showed both significant seasonal decreases and increases in the presence of P. cuspidatum (increases in August and decreases in July). Fish blood and hepatic IL-10 and IFN-γ levels (together with fish sampled in September) significantly increased in the P. cuspidatum group sampled in August, while those of TNF-α (10% sandwich-like, P. cuspidatum), IL-1β (P. cuspidatum), IL-8 (5% sandwich-like in September, S905S) significantly decreased. Heat shock proteins 60 and 70 levels significantly increased in the P. cuspidatum group, and complement C3 and C4 concentrations significantly increased in S905S. This study demonstrated that enhanced immunity through the regulation of pro- and anti-inflammatory proteins was sustained throughout development until harvest, particularly in fish grown with P. cuspidatum.

The level of IL-6 was associated with sleep disturbances in patients with major depressive disorder

Purpose: Major depression disorder (MDD) was associated with inflammatory processes, but association results of inflammatory syndrome and MDD were inconsistent. To provide more evidence, we measured the plasma levels of IL-1β, IL-6, interferon (INT)-α2, INT-γ, and tumor necrosis factor (TNF)-α in patients having MDD and explored correlations between the five proinflammatory cytokines and specific depressive symptoms. Patients and methods: Plasma concentrations of IL-1β, IL-6, INT-α2, INT-γ, and TNF-α were measured using ELISA for 44 MDD patients and 54 healthy controls. Patients with MDD were assessed on the 17-item Hamilton Depression Rating Scale (HAMD-17), and a total score and five syndrome scores were acquired. Results: IL-6 levels in depressed patients were significantly elevated than in healthy controls, but no significant differences were observed in the levels of INF-α2, INF-γ, IL-1β, or TNF-α. In addition, correlation analysis revealed that sleep disturbances positively correlated with IL-6. Although there was no significant difference between the two groups in the levels of INF-α2, a significant positive correlation between IFN-α2 and retardation was observed. Conclusion: Elevated IL-6 levels were observed in MDD patients and IL-6 may correlate with sleep disturbances.

Medial Forebrain Bundle Deep Brain Stimulation Reverses Anhedonic-Like Behavior in a Chronic Model of Depression: Importance of BDNF and Inflammatory Cytokines

Deep brain stimulation (DBS) of the medial forebrain bundle (MFB) displays a promising antidepressant effects in patients with treatment-refractory depression; however, a clear consensus on underlying mechanisms is still enigmatic. Herein, we investigated the effects of MFB-DBS on anhedonic-like behavior using the Froot Loops® consumption in a chronic unpredictable mild stress (CUS) model of depression, biochemical estimation of peripheral and central inflammatory cytokines, stress hormone, and brain-derived neurotrophic factor (BDNF). Seven days of MFB-DBS significantly reversed the 42-day CUS-generated anhedonic-like phenotype (p < 0.02) indicated by an increase in Froot Loops® consumption. Gross locomotor activity and body weight remained unaffected across the different groups. A dramatic augmentation of adrenocorticotropic hormone levels was seen in the plasma and cerebrospinal fluid (CSF) samples of CUS rats, which significantly reduced following MFB-DBS treatment. However, C-reactive protein levels were found to be unaffected. Interestingly, decreased levels of BDNF in the CUS animals were augmented in the plasma, CSF, and hippocampus following MFB-DBS, but remained unaltered in the nucleus accumbens (NAc). While multiplex assay revealed no change in the neuronal levels of inflammatory cytokines including IL-1α, IL-4, IL-10, IL-12, IL-13, and IL-17 in the neuroanatomical framework of the hippocampus and NAc, increased levels of IL-1β, IL-2, IL-5, IL-6, IL-7, IL-18, TNF-α, and INF-γ were seen in these brain structures after CUS and were differentially modulated in the presence of MFB stimulation. Here, we show that there is dysregulation of BDNF and neuroimmune mediators in a stress-driven chronic depression model, and that chronic MFB-DBS has the potential to undo these aberrations.

Expression levels of interferon-ɣ and type 2 deiodinase in patients diagnosed with recurrent depressive disorders

BACKGROUND

Thyroid hormones (TH) are involved in modulation of the immune system and inflammation. TH dysregulation is associated with depressive disorders. The iodothyronine deiodinases (DIOs), the key enzymes for TH synthesis, can be affected and induced by pro-inflammatory cytokines. We aimed to investigate the levels of and correlation between type 2 DIO (DIO2) and interferon-gamma (IFN-ɣ) in patients with recurrent depressive disorders (rDD).

METHODS

Data from 91 rDD patients and 105 healthy controls were analyzed. The diagnoses are based on the ICD-10 criteria (F33.0-F33.8). Expression levels of DIO2 and IFN-ɣ were estimated using the method based on the polymerase chain reaction and the enzyme-linked immunosorbent assay (ELISA).

RESULTS

The DIO2 expression on mRNA/protein levels in rDD patients (both female and males) was reduced as compared with the control subjects. No correlation between DIO2 and IFN-ɣ expression was observed.

CONCLUSION

This is the first study to reveal that one may cautiously suggest that DIO2 may be involved in the development and/or progression of rDD. The mechanisms of TH regulation on depression, however, need further investigation.

Chemokines in depression in health and in inflammatory illness: a systematic review and meta-analysis

Inflammatory illness is associated with depression. Preclinical work has shown that chemokines are linked with peripheral-central crosstalk and may be important in mediating depressive behaviours. We sought to establish what evidence exists that differences in blood or cerebrospinal fluid chemokine concentration discriminate between individuals with depression and those without. Following PRISMA guidelines, we systematically searched Embase, PsycINFO and Medline databases. We included participants with physical illness for subgroup analysis, and excluded participants with comorbid psychiatric diagnoses. Seventy-three studies met the inclusion criteria for the meta-analysis. Individuals with depression had higher levels of blood CXCL4 and CXCL7 and lower levels of blood CCL4. Sensitivity analysis of studies with only physically healthy participants identified higher blood levels of CCL2, CCL3, CCL11, CXCL7 and CXCL8 and lower blood levels of CCL4. All other chemokines examined did not reveal significant differences (blood CCL5, CCL7, CXCL9, CXCL10 and cerebrospinal fluid CXCL8 and CXCL10). Analysis of the clinical utility of the effect size of plasma CXCL8 in healthy individuals found a negative predictive value 93.5%, given the population prevalence of depression of 10%. Overall, our meta-analysis finds evidence linking abnormalities of blood chemokines with depression in humans. Furthermore, we have demonstrated the possibility of classifying individuals with depression based on their inflammatory biomarker profile. Future research should explore putative mechanisms underlying this association, attempt to replicate existing findings in larger populations and aim to develop new diagnostic and therapeutic strategies.

Acupuncture alters pro-inflammatory cytokines in the plasma of maternally separated rat pups

OBJECTIVE

To investigate the potential alleviating effects of acupuncture on maternal separation (MS)-induced changes in plasma pro-inflammatory cytokine levels of rat pups.

METHODS

On postnatal day 15, rat pups were randomly assigned to 4 groups (n=6 per group) using a random number table: normal, MS, MS with acupuncture stimulation at Shenmen (HT 7) acupoint (MS+HT 7), and MS with acupuncture stimulation at Chengshan (BL 57) acupoint (MS+BL 57) groups. Rat pups in the normal group were housed with their mothers under standard conditions; those in the MS, MS+HT 7 and MS+BL 57 groups were maternally separated and individually maintained. Acupuncture stimulation was performed at HT 7 or BL 57 acupoints once a day for 7 consecutive days. A tail suspension test was performed to measure immobility time of rats and the plasma was collected on postnatal day 21, then levels of corticosterone (CORT), interleukin (IL)-1β, IL-6 and glial cell-derived neurotrophic factor (GDNF) in plasma were measured.

RESULTS

Compared with the normal group, the immobility time and the plasma levels of CORT, IL-1β, IL-6 and GDNF in the MS group were significantly increased (P<0.05 or P<0.01). Compared with the MS group, the immobility time and the plasma levels of CORT, IL-1β, IL-6 and GDNF were significantly reduced in the MS+HT 7 group (P<0.05 or P<0.01). Moreover, the immobility time and plasma levels of IL-1β and IL-6 in the MS+HT 7 group were significantly lower than those in the MS+BL 57 group (P<0.05).

CONCLUSION

Acupuncture stimulation at HT 7 can alleviate the behavioral impairment and changes of the cytokines by MS, indicating that acupuncture can help to relieve MS-induced depression.

Dietary supplementation with rutin has pro-/anti-inflammatory effects in the liver of juvenile GIFT tilapia, Oreochromis niloticus

Dietary supplementation with rutin may have some pharmacological qualities including anti-inflammatory effects. Kupffer cell activation resulted in increased transcription of pro- and anti-inflammatory cytokines. The main purpose of this study was to investigate the pro- and anti-inflammatory activities in juvenile freshwater tilapia, Oreochromis niloticus, in response to 0.1 or 0.3 g/kg dietary supplementation of rutin. Results showed that hepatic IgM, anti-inflammatory-cytokines, and pro-inflammatory cytokines were significantly decreased in groups treated with high doses of rutin. Hepatic IgM and anti-inflammatory cytokines (IL-10 and IFN-γ) transcripts were significantly decreased, whereas the transcripts of the pro-inflammatory cytokines, TNFα and IL-1β were significantly decreased, whereas IL-8 was significantly increased. The number of Kupffer cells in rutin-treated groups was significantly decreased, and scanning electron micrographs showed that rutin enriched the number of gut microvilli and secretion pits. With the phenomena of cell apoptosis occurred in the rutin groups, the present study demonstrated that optimum levels of rutin may be beneficial but excessive level may cause liver impairment, which may be absorbed by the gut and then transported to the liver.

A meta-analysis of chemokines in major depression

Chemokines are increasingly recognised as playing a role in depression. Here we meta-analyse the data on concentrations of all chemokines in patients diagnosed with a major depression versus healthy controls. We included studies which utilised Diagnostic and Statistical Manual (DSM)-IV diagnostic criteria for major depression, participants free from major medical conditions, studies with healthy controls, and unstimulated measurements of chemokines. We only included chemokines which had ≥3 studies performed. Two chemokines and 15 studies in total met criteria for this meta-analysis; 8 for Monocyte Chemotactic Protein (MCP)-1/CCL2 (n=747), and 7 for Interleukin (IL)-8/CXCL8 (n=560). There were significantly higher concentrations of CCL2/MCP-1 in depressed subjects compared with control subjects - overall mean difference of 36.43pg/mL (95% CI: 2.43 to 70.42). There was significant heterogeneity across these studies (I2=98.5%). The estimates of mean difference between the control and depression groups did not remain significant when the trim-and-fill procedure was used to correct for publication bias. There was no significant difference in concentrations of IL-8/CXCL8 in depressed subjects compared with control subjects. Significant heterogeneity was found across these studies (I2=96.7%). The estimates of mean difference between the control and depression groups remained non-significant when the trim-and-fill procedure was used to correct for publication bias. This meta-analysis reports significantly heterogeneity in this field among studies. There are higher concentrations of the chemokine MCP-1/CCL2 in depressed subjects compared with control subjects, and no differences for IL-8/CXCL8. More high quality research and consistent methodologies are needed in this important area of enquiry.

Changes in the levels of kynurenic acid and selected proinflammatory cytokines after pharmacological treatment and electroconvulsive therapy (ECT) in patients with depressive disorder

The aim of the present study was to compare the concentrations of KYNA, 3-OH-KYN and the cytokines TNF-α and IL-6 in patients with depression vs. healthy controls as well as in patients with depression treated pharmacologically vs. those treated using ECT. We also evaluated the relationship between the concentrations of KYNA, 3-OH-KYN and the cytokines TNF-α and IL-6 and clinical improvement measured on the MADRS scale in patients treated pharmacologically and those treated with ECT.

Subjects and methods: The study group comprised 29 patients aged 28 to 60 years with a diagnosis of a major depressive episode. Eleven of the patients received pharmacological treatment and 18 were treated with ECT.

Patients were assayed for serum levels of KYNA and the cytokines IL-6 and TNF-α. Clinical improvement was measured on the MADRS depression rating scale and the clinical global impression (CGI) scale.

Results: Significant differences were found in KYNA levels between depressive patients and healthy controls. Pharmacological treatment significantly contributed to the increase in KYNA levels and ECT – to the increase in TNF-α levels in depressive patients.

Conclusions:

Levels of serum immunomodulators and alterations with electroconvulsive therapy in treatment-resistant major depression

Studies in recent years have indicated that neuroimmunological events and immune activation may have a place in the etiology of depression. It has been suggested from data that there is a causal relationship between activation of the immune system and excessive release of proinflammatory cytokines, such as interleukin 1 (IL-1), IL-6, and tumor necrosis factor-alpha (TNF-alpha), and the etiology of depression. Although the mechanism of action of electroconvulsive therapy (ECT) is unclear, there is evidence that it can reduce cytokines and immune system changes. In our study, we aimed to determine how levels of serum immunomodulators were affected by ECT in major depression patients. This study was conducted on 50 patients with treatment-resistant major depression. The data of the patients were compared with 30 healthy individuals with similar demographic characteristics. A clinical response occurred in the patients and at the end of therapy, IL-1, IL-6, TNF-alpha, IL-10, IL-4, and interferon-gamma levels were measured. The disease severity was assessed with the 17-item Hamilton Depression Rating Scale. Data analysis was performed using SPSS Version 15. Significant differences were determined between the patients with major depression and control group with respect to basal serum IL-1, IL-6, TNF-alpha, IL-10, IL-4, and interferon-gamma levels. ECT treatment was shown to reduce these differences. ECT may cause significant changes in the activity of the immune system. The consideration of the relationship between the immune endocrine neurotransmitter systems could contribute to new theories regarding the mechanism of antidepressant treatment and biology of depression.

A Meta-Analysis of Oxidative Stress Markers in Depression

OBJECT

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

METHODS

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

RESULTS

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

CONCLUSION

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

Understanding Disease-Drug Interactions in Cancer Patients: Implications for Dosing Within the Therapeutic Window

The human inflammatory response can result in the alteration of drug clearance through effects on metabolizing enzymes or transporters. In this article we briefly review the theory of how cancer can lead to indirect changes in drug metabolism, review acute phase proteins and cytokines as markers of changes in cytochrome P450 (CYP) activity in cancer patients, and provide clinical case examples of how the inflammation in advanced cancer patients can lead to altered CYP-mediated drug clearance.

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.

Ethanol extracts from Hemerocallis citrina attenuate the upregulation of proinflammatory cytokines and indoleamine 2,3-dioxygenase in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Hemerocallis citrina, a traditional herbal medicine, has been used for the improvement of behavioral and emotional status in Eastern-Asia countries. Previous studies in our laboratory demonstrated that ethanol extracts from Hemerocallis citrina (HCE) enhanced monoamines and brain-derived neurotrophic factor (BDNF) in depression-like model of rodents.

MATERIALS AND METHODS

The present study extends earlier works on the role of anti-inflammation in regulating the antidepressant-like actions of HCE in rats exposed to chronic unpredictable mild stress (CUMS). Frontal cortex and hippocampal proinflammatory cytokines levels and indoleamine 2,3-dioxygenase (IDO) activity were measured after 4-week HCE treatment in the CUMS an control rats.

RESULTS

Chronic administration of HCE reversed the decreased sucrose preference in sucrose preference test. In addition, we also found that HCE inhibited interleukin-1 beta (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) expression, as well as IDO activity in frontal cortex and hippocampus, which were increased in rats exposed to CUMS.

CONCLUSIONS

Combining with our previous studies, our present finding suggests that the anti-inflammatory property of HCE might play a crucial role in its antidepressant-like effect through, at least in part, the restoration or improvement of monoaminergic and neurotrophin systems.

Metabolic syndrome: differences between psychiatric and internal medicine patients

OBJECTIVES

The existence of specific features of Metabolic Syndrome (MetS) in psychiatric population in comparison to not psychiatric patients has not been systematically investigated. The purpose of this study is to evaluate the differences of MetS among a group of psychiatric patients and a group of internal medicine patients in terms of anthropometric measurements, biochemical variables, and cardiovascular risk.

METHODS

We enrolled 83 psychiatric inpatients under pharmacological treatment (schizophrenia n = 24, bipolar disorder n = 27, major depression n = 14, other n = 18) and 77 internal medicine patients visited for supposed MetS as affected by overweight or arterial hypertension.

RESULTS

Psychiatric patients differed from control subjects by age (yrs) (47 +/- 9 vs. 52 +/- 8.6, p = 0.001), waist circumference (cm) (111.9 +/- 10.9 vs. 106 +/- 12.6, p = 0.02), HDL cholesterol (mg/dl) (36.8 +/- 7 vs. 48 +/- 11.3, p = 0.001), serum insulin (microU/ml) (26 +/- 12.5 vs. 16.4 +/- 8.8, p = 0.001), triglyceride/HDL cholesterol ratio (4.8 +/- 2.7 vs. 3.3 +/- 2.2, p = 0.01). Female psychiatric patients had higher levels of triglycerides (mg) (178 + 86 vs. 115 + 53, p = 0.002) and of HOMA index (7.8 + 5 vs. 3.8 + 3.3, p = 0.005). Triglycerides and triglycerides/HDL ratio levels were higher in Unipolar Depression. A positive association was found between antidepressant drug treatment with triglycerides and triglycerides/HDL ratio levels, neuroleptic treatment with the HOMA index, and antipsychotics drugs with the Framingham index.

LIMITATIONS

Psychiatric study population numerosity and duration of psychiatric illness and drug treatment.

CONCLUSIONS

Specific features of MetS in psychiatric population are mainly represented by young age of onset, hyperinsulinemia, increased abdominal adiposity, and low HDL cholesterol whose common denominator may be insulin-resistance.

Depression is improved when low-dose tacrolimus is given to rheumatoid arthritis patients showing an inadequate response to biologic agents

PURPOSE

Depression in rheumatoid arthritis (RA) patients is more severe than in healthy people. Herein, we report improved depression in RA patients using biologic agents. We examined whether depression was improved by tacrolimus combination therapy when biologic agents were ineffective.

METHOD

The study included 13 RA patients who used biologic agents. The following methods were used before the initiation of tacrolimus combination therapy and at 14 and 30 weeks after treatment initiation: the Zung self-rating depression scale (SDS) to evaluate depression state, disease activity score 28/erythrocyte sedimentation rate (DAS28), tender joint counts, swollen joint counts, a patient global assessment to evaluate RA disease activity, and the modified health assessment questionnaire (mHAQ) to evaluate quality of life.

RESULTS

The SDS scores before the initiation of tacrolimus combination therapy and at 14 and 30 weeks after treatment initiation were 45.2 ± 10.6, 44.8 ± 12.8, and 41.6 ± 11.2 (p = 0.047), respectively, indicating significant improvement. The DAS28 was 5.0 ± 1.3 prior to treatment, 3.8 ± 1.3 at 14 weeks, and 3.5 ± 0.9 at 30 weeks, demonstrating significant improvement at both 14 and 30 weeks (p < 0.001). The mHAQ score changed from 0.60 ± 0.45 at baseline to 0.54 ± 0.52 and 0.38 ± 0.43 at 14 and 30 weeks, respectively. The mHAQ score was significantly lower at 30 weeks when compared to baseline (p = 0.013).

CONCLUSION

Tacrolimus combination therapy does not directly improve depression in RA patients, but it is possible that the observed improvement in depression accompanies the improvement in the secondary failure of RA.