Dysregulated relationship of inflammation and oxidative stress in major depression

Oxidative balance and mental health: Exploring the link between prooxidant-antioxidant balance and depression in hypertensive and normotensive individuals, accounting for sex differences

BACKGROUND

Existing studies have suggested a link between oxidative stress levels and depression. Additionally, factors such as gender and conditions like hypertension have been shown to influence oxidative stress. This ten-year follow-up cohort study aims to examine the association between prooxidant-antioxidant balance (PAB) and the onset of depression and its symptoms in both hypertensive and normotensive individuals, while considering gender differences.

METHODS

The data for this study was obtained from the Mashhad Stroke and Heart Atherosclerotic Disorder (MASHAD) study, a cohort study conducted in eastern Iran. Serum PAB levels were measured in 1702 hypertensive and 4096 normotensive individuals aged 35 to 65 years. After ten years, the participants' depression status was evaluated using the Beck questionnaire, and depression symptoms were investigated using the BDI-II structural model, which includes somatic, affective, and cognitive symptoms.

RESULT

The analysis indicates that in hypertensive male participants, the highest tertile of PAB is associated with an increased risk of depression (β: 1.22, 95 % CI: -0.046, 2.485; P = 0.059) and symptoms of depression, including cognitive (β: 2.937, 95 % CI: 0.511, 5.362; P = 0.018) and somatic (β: 2.654, 95 % CI: 0.37, 4.939; P = 0.023) symptoms. However, there was no significant association between affective symptoms and PAB tertiles. Additionally, there was no significant link between depression and depressive symptoms in female hypertensive and normotensive individuals.

CONCLUSION

In male hypertensive patients, but not in normotensive individuals of both genders and hypertensive women, depression and its associated symptoms, including somatic and cognitive symptoms, are associated with elevated levels of oxidative stress, as evidenced by higher serum PAB values. PAB is not associated with affective symptoms. Future studies should focus on the gender-specific nature of this relationship and work to clarify its underlying mechanisms.

Exploring the L-shaped relationship between Atherogenic Index of Plasma and depression: Results from NHANES 2005-2018

BACKGROUND

The Atherogenic Index of Plasma (AIP) is a novel metric linked to several diseases. However, there is inadequate evidence to investigate the relationship between AIP and depression. Therefore, we aim to elucidate the non-linear association between AIP and depression.

METHODS

12,453 participants from the National Health and Nutrition Examination Survey (NHANES) 2005-2018 were included. The AIP was calculated as log10 (triglycerides/high-density lipoprotein cholesterol). The Patient Health Questionnaire (PHQ-9) was used to identify depression (PHQ-9 ≥ 10). Weighted multivariate logistic regression, restricted cubic splines (RCS) models, subgroup analysis, and interaction tests were employed to reveal the relationship between AIP and depression.

RESULTS

AIP was found to be significantly correlated with depression. In the fully adjusted model, elevated AIP levels were associated with higher odds of depression (odds ratio [OR] = 1.50; 95 % CI: 1.06-2.12). The RCS analysis indicated an L-shaped pattern in the relationship between depression and AIP, with inflection points at -0.289. Beyond this inflection point, individuals with elevated AIP levels were associated with higher odds of depression (OR = 2.25; 95 % CI: 1.49-3.39). Notably, the association was particularly pronounced among individuals with diabetes.

LIMITATION

This cross-sectional study is unable to establish causal relationships.

CONCLUSION

There was an L-shaped association between AIP and depression among US adults. AIP has the potential value as a biological marker for depression, and maintaining AIP values below a certain threshold may help in managing depression.

Curcumin Reduces Depression in Obese Patients with Type 2 Diabetes: A Randomized Controlled Trial

Type 2 diabetes and depression co-occur in a bidirectional manner. Curcumin supplements exhibit antidepressant effects that may mitigate depression by modulating neurotransmitters and reducing inflammatory and oxidative stress pathways. This study aimed to evaluate the efficacy of curcumin in improving depression severity in obese type 2 diabetes patients. The study employed a randomized, double-blind, placebo-controlled trial design with 227 participants. The primary end-point was depression severity assessed using the Patient Health Questionnaire-9. Biomarkers were measured at baseline and at 3-, 6-, 9-, and 12-month intervals. The biomarkers assessed were serotonin levels, pro-inflammatory cytokines (interleukin-1 beta, interleukin-6, tumor necrosis factor-alpha), antioxidant activities (total antioxidant status, glutathione peroxidase, and superoxide dismutase), and malondialdehyde. After 12 months, the curcumin group exhibited significantly improved depression severity (p = 0.000001). The curcumin group had higher levels of serotonin (p < 0.0001) but lower levels of interleukin-1 beta, interleukin-6, and tumor necrosis factor-alpha (p < 0.001 for all) than the placebo group. Total antioxidant status, glutathione peroxidase activity, and superoxide dismutase activity were elevated in the curcumin group, whereas malondialdehyde levels were greater in the placebo group (p < 0.001 for all). These findings suggest curcumin may have antidepressant effects on obese type 2 diabetes patients.

Urea Level and Depression in Patients with Chronic Kidney Disease

Depression is common in patients with chronic kidney disease (CKD). Experimental studies suggest the role of urea toxicity in depression. We assessed both the incidence of antidepressant prescriptions and depressive symptoms (measured by CESD (Center for Epidemiologic Depression) scale) in 2505 patients with CKD (Stage 3-4) followed up over 5 years in the Chronic Kidney Disease Renal Epidemiology and Information Network (CKD-REIN) cohort. We used a joint model to assess the association between the serum urea level and incident antidepressant prescriptions, and mixed models for the association between the baseline serum urea level and CESD score over the 5-year follow-up. Among the 2505 patients, 2331 were not taking antidepressants at baseline. Of the latter, 87 started taking one during a median follow-up of 4.6 years. After adjustment for confounding factors, the hazard ratio for incident antidepressant prescription associated with the serum urea level (1.28 [95%CI, 0.94,1.73] per 5 mmol/L increment) was not significant. After adjustment, the serum urea level was associated with the mean change in the CESD score (β = 0.26, [95%CI, 0.11,0.41] per 5 mmol/L increment). Depressive symptoms burden was associated with serum urea level unlike depression events. Further studies are needed to draw firm conclusions and better understand the mechanisms of depression in CKD.

Sleep duration and leisure activities are involved in regulating the association of depressive symptoms, muscle strength, physical function and mild cognitive impairment

Background

In order to lessen the burden of Alzheimer's disease (AD), timely and efficient management and intervention methods for mild cognitive impairment (MCI) are crucial. MCI is seen as a transitional stage between normal aging and dementia. Although sarcopenia is an important risk factor for MCI, it is unclear what factors mediates and regulates the brain-muscle communication. Our objective was to investigate the indirect moderating effects of sleep duration and leisure activity on depressive symptoms, sarcopenia and MCI.

Method

Panel data from the 2015 China Health and Retirement Longitudinal Study (CHARLS) database was used in this investigation. we used Bootstrap sampling to determine the relationship between sleep duration, leisure activity, depressive symptoms, sarcopenia, and MCI in mediation and indirect moderation models. The outcome measurements were odds ratio (OR) and confidence interval (CI).

Result

After adjusting for confounding variables, we discovered that sarcopenia and its traits, such as handgrip strength, gait speed, standing test, and muscle mass, were significantly correlated with MCI. Second, the results implied that depressive symptoms played a role in modulating the link between physical function, muscle strength, and MCI. This moderating effect was impacted by short sleep duration and moderate to high levels of leisure activities.

Conclusion

We discovered that MCI was highly correlated not only with physical function and muscle strength but also with depressed symptoms, which acted as a partially mediating factor in this connection. Handgrip strength, gait speed, and standing test mediated the correction of MCI caused by depression symptoms. Importantly, leisure activities and sleep duration had indirect moderating effects on the above associations, and future management policies should take these factors into account.

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.

5-HTP inhibits eosinophilia via intracellular endothelial 5-HTRs; SNPs in 5-HTRs associate with asthmatic lung function

Background

Previous research showed that 5-hydroxytryptophan (5HTP), a metabolic precursor of serotonin, reduces allergic lung inflammation by inhibiting eosinophil migration across endothelial monolayers.

Objective

It is unknown if serotonin receptors are involved in mediating this 5HTP function or if serotonin receptor (HTR) single nucleotide polymorphisms (SNPs) associate with lung function in humans.

Methods

Serotonin receptor subtypes were assessed by qPCR, western blot, confocal microscopy, pharmacological inhibitors and siRNA knockdown. HTR SNPs were assessed in two cohorts.

Results

Pharmacological inhibition or siRNA knockdown of the serotonin receptors HTR1A or HTR1B in endothelial cells abrogated the inhibitory effects of 5HTP on eosinophil transendothelial migration. In contrast, eosinophil transendothelial migration was not inhibited by siRNA knockdown of HTR1A or HTR1B in eosinophils. Surprisingly, these HTRs were intracellular in endothelial cells and an extracellular supplementation with serotonin did not inhibit eosinophil transendothelial migration. This is consistent with the inability of serotonin to cross membranes, the lack of selective serotonin reuptake receptors on endothelial cells, and the studies showing minimal impact of selective serotonin reuptake inhibitors on asthma. To extend our HTR studies to humans with asthma, we examined the CHIRAH and GALA cohorts for HTR SNPs that affect HTR function or are associated with behavior disorders. A polygenic index of SNPs in HTRs was associated with lower lung function in asthmatics.

Conclusions

Serotonin receptors mediate 5HTP inhibition of transendothelial migration and HTR SNPs associate with lower lung function. These results may serve to aid in design of novel interventions for allergic inflammation.

Comparison of the associations between Life's Essential 8 and Life's Simple 7 with depression, as well as the mediating role of oxidative stress factors and inflammation: NHANES 2005-2018

BACKGROUND

Cardiovascular health (CVH) is closely associated with depression. However, Life's Essential 8 (LE8), a novel CVH measure, has not yet been clearly linked to depression. This study aims to explore the association between LE8 and depression, compare its advantages over Life's Simple 7 (LS7), and investigate the mediating effects of oxidative stress and inflammation.

METHODS

This study investigated cross-sectional data of adults aged 20 and above from National Health and Nutrition Examination Survey (NHANES) 2005 to 2018. The LE8 score (ranging from 0 to 100) was derived from the American Heart Association's definition, based on the unweighted average of 8 metrics, classified as low cardiovascular health (CVH) (0-49), moderate CVH (50-79), and high CVH (80-100). Similar to LE8, LS7 scores were categorized into inadequate (0-7), average (8-10), or optimal (11-14) after calculating the unweighted mean of each component. Depression was diagnosed using the Patient Health Questionnaire (PHQ-9), with a score of ≥10 defining depression. Adjusted for sociodemographic factors and other risk factors for depression, weighted logistic regression and restricted cubic spline analysis were used to explore the correlation. Receiver operating characteristic (ROC) curves were used to study the associations between CVH scores and depression. Subsequently, subgroup analysis and sensitivity analysis were conducted, followed by an exploration of the mechanisms involved.

RESULTS

A total of 7 cycles from 2005 to 2018 contained complete data. Weighted logistic regression showed that both LS7 and LE8 were significantly associated with depression. Specifically, for LE8, after adjustment, the risk of depression decreased by 52 % for moderate CVH compared to low CVH (OR: 0.48, 95 % CI: 0.41-0.57, P < 0.0001), while the risk decreased by 80 % for high CVH (OR: 0.20, 95 % CI: 0.15-0.26, P < 0.0001, Ptrend < 0.0001). For LS7, after adjustment, compared with inadequate CVH, the risk of depression decreased by 49 % for average CVH (OR: 0.51, 95 % CI: 0.34-0.78, P = 0.002), and by 55 % for optimal CVH (OR: 0.45, 95 % CI: 0.27-0.74, P = 0.002, Ptrend < 0.0001). Area under ROC curves for predicting depression were 0.672 (95 % CI, 0.66-0.684; P < 0.001) and 0.605 (95 % CI, 0.59-0.619; P < 0.001) for LE8 and LS7 (PDeLong < 0.001), respectively. Sensitivity analysis demonstrated the robustness of the association. GGT and WBC jointly mediated 9.62 % of this association (all P < 0.001).

LIMITATIONS

The cross-sectional study cannot infer causality.

CONCLUSIONS

The association between Life's Essential 8 and depression was stronger and more practical. Oxidative stress and inflammation mediate this association. Individuals with extremely poor cardiovascular health have a 7-fold increased risk of depression, highlighting the necessity of maintaining at least moderate cardiovascular health.

Major depressive disorder: hypothesis, mechanism, prevention and treatment

Worldwide, the incidence of major depressive disorder (MDD) is increasing annually, resulting in greater economic and social burdens. Moreover, the pathological mechanisms of MDD and the mechanisms underlying the effects of pharmacological treatments for MDD are complex and unclear, and additional diagnostic and therapeutic strategies for MDD still are needed. The currently widely accepted theories of MDD pathogenesis include the neurotransmitter and receptor hypothesis, hypothalamic-pituitary-adrenal (HPA) axis hypothesis, cytokine hypothesis, neuroplasticity hypothesis and systemic influence hypothesis, but these hypothesis cannot completely explain the pathological mechanism of MDD. Even it is still hard to adopt only one hypothesis to completely reveal the pathogenesis of MDD, thus in recent years, great progress has been made in elucidating the roles of multiple organ interactions in the pathogenesis MDD and identifying novel therapeutic approaches and multitarget modulatory strategies, further revealing the disease features of MDD. Furthermore, some newly discovered potential pharmacological targets and newly studied antidepressants have attracted widespread attention, some reagents have even been approved for clinical treatment and some novel therapeutic methods such as phototherapy and acupuncture have been discovered to have effective improvement for the depressive symptoms. In this work, we comprehensively summarize the latest research on the pathogenesis and diagnosis of MDD, preventive approaches and therapeutic medicines, as well as the related clinical trials.

Joint association of heavy metals and polycyclic aromatic hydrocarbons exposure with depression in adults

BACKGROUND

Heavy metals (HMs) and polycyclic aromatic hydrocarbons (PAHs) represent significant components of environmental pollution, typically occurring as mixtures, raising concerns about their potential impact on human health. However, the combined effect of HMs and PAHs exposure on depression has not been explored.

METHODS

Leveraging National Health and Nutrition Examination Survey (NHANES) data spanning 2005 to 2016, we employ survey-weighted multiple logistic regression models to probe the interrelation between HMs, PAHs, and depression. This exploration is complemented by age and gender-stratified analyses, as well as a determination of the dose-response linkage via restricted cubic spline regression. Furthermore, the combined impact of HMs and PAHs on depression was evaluated through a range of statistical methodologies.

RESULTS

The study encompasses 7732 adults. Our findings unveil notable associations, indicating the significant influence of cadmium (Cd), lead (Pb), and all six PAHs metabolites on depression. Moreover, mixed exposure to HMs and PAHs emerges as a substantial contributor to an augmented depression risk, with Cd, Pb, 1-hydroxynaphthalene (1-NAP), 2-hydroxyfluorene (2-FLU), and 1-hydroxypyrene (1-PYR) likely driving this positive relationship. Intriguingly, subgroup analyses highlight greater prominence of these connections among individuals aged 20-59 and among women. Furthermore, the results tentatively suggest a potential interplay between Cd and 2-NAP in relation to depression.

CONCLUSION

This study posits that exposure to both individual and combined HMs and PAHs may be associated with an elevated risk of depression. Further prospective investigations are warranted to substantiate these findings.

The effects of curcumin and sertraline on stress-induced changes in the stomach tissues of rats

Exposure to stressors can cause functional disorders and structural damage to the stomach. Sertraline (SER) is an antidepressant and curcumin (CUR) is a natural compound with many properties. The current study aimed to investigate the impacts of stress, SER, and CUR on the stomach tissue using stereological methods. In total, 24 male and 24 female Sprague-Dawley rats were divided into four groups. In the control group, the rats were not exposed to stress. However, the animals in stress, SER and, CUR groups were exposed to daily stress and were orally fed with distilled water, SER (10 mg/kg/day), and CUR (100 mg/kg/day), respectively. The volume, surface area, and number of nerve, parietal, and chief cells were evaluated by stereological methods. Results showed that stress increased the stomach and its mucosa and submucosa volumes, while it decreased the surface area of the mucosa. Furthermore, this disorder increased the number of neurons in the submucosa and myenteric plexuses while it decreased the number of parietal and chief cells. However, treating stressed rats with SER or CUR could prevent these changes. The results showed that the consumption of SER or CUR could be used as a preventive or adjunctive treatment for stressful situations.

Commentary: Discussing the antidepressant potential of silymarin

The therapeutic potential of diet, dietary supplements, herbal remedies, and nutraceuticals for treatment of depression and anxiety is being increasingly explored. In this commentary, we discuss the recent findings on the antidepressant potential of silymarin (SILY) in mice and present an alternative approach. We highlight the extensive research on another phytochemical, curcumin, for the treatment of depression and anxiety. Finally, we suggest a future application, which investigates the potential synergistic effects of combined treatment with SILY and curcumin for depression.

Oxidative balance scores and depressive symptoms: Mediating effects of oxidative stress and inflammatory factors

BACKGROUND

Few studies have examined the combined effects of dietary and lifestyle factors on depressive symptoms. This study aimed to evaluate the association between oxidative balance score (OBS) and depressive symptoms and the underlying mechanisms.

METHODS

A total of 21,283 adults from the 2007 to 2018 National Health and Nutrition Examination Survey (NHANES) were included. Depressive symptoms were defined as a total score of ≥10 on the Patient's Health Questionnaire (PHQ-9). Twenty dietary and lifestyle factors were selected to calculate the OBS. Multivariable logistic regression analyses were used to evaluate the association between OBS and depression risk. Mediation analyses were conducted to explore the roles of oxidative stress and inflammatory markers.

RESULTS

In multivariate model, a significant negative association was found between OBS and depression risk. Compared with those in OBS tertile 1, participants in tertile 3 had lower odds of developing depressive symptoms (OR:0.50; 95 % CI:0.40-0.62; P < 0.001). Restricted cubic splines showed a linear relationship between OBS and depression risk (P for nonlinearity = 0.67). Moreover, higher OBS was found to be associated with lower depression scores (β = -0.07; 95 % CI:-0.08, -0.05; P < 0.001). GGT concentrations and WBC counts mediated the association between OBS and depression scores by 5.72 % and 5.42 %, respectively (both P < 0.001), with a joint mediated effect of 10.77 % (P < 0.001).

LIMITATIONS

This study was a cross-sectional design making it difficult to infer a causal association.

CONCLUSIONS

OBS is negatively associated with depression, which may be mediated in part by oxidative stress and inflammation.

Effects of continuous positive airway pressure on comprehensive geriatric assessment and cognitive function in elderly patients with obstructive sleep apnea syndrome

Obstructive sleep apnea syndrome (OSAS) can lead to cognitive impairment and depression affecting memory, attention, and executive functions. Continuous positive airway pressure (CPAP) treatment seems to be able to revert changes in brain networks and neuropsychological tests correlated to OSAS. The aim of the present study was to evaluate the effects of a 6-month treatment with CPAP on functional, humoral and cognitive parameters in a cohort of elderly OSAS patients with several comorbidities. We enrolled 360 elderly patients suffering from moderate to severe OSAS and indication for nocturnal CPAP. At baseline the Comprehensive Geriatric Assessment (CGA) revealed a borderline Mini-Mental State Examination (MMSE) score that improved after 6-month treatment with CPAP (25.3 ± 1.6 vs 26 ± 1.5; p < 0.0001), as well as the Montreal Cognitive Assessment (MoCA) showed a mild improvement (24.4 ± 2.3 vs 26.2 ± 1.7; p < 0.0001). Moreover, functionality activities increased after treatment, as documented by a short physical performance battery (SPPB) (6.3 ± 1.5 vs 6.9 ± 1.4; p < 0.0001). Reduction of the Geriatric Depression Scale (GDS) from 6.0 ± 2.5 to 4.6 ± 2.2 (p < 0.0001) was also detected. Changes of homeostasis model assessment (HOMA) index, oxygen desaturation index (ODI), sleep-time spent with saturation below 90% (TC90), peripheral arterial oxyhaemoglobin saturation (SpO2), apnea-hypopnea index (AHI) and estimation of glomerular filtration rate (eGFR), contributed, respectively, to 27.9%, 9.0%, 2.8%, 2.3%, 1.7% and 0.9% of MMSE variability for a total of 44.6% of MMSE variations. GDS score changes were due to the improvement of AHI, ODI and TC90, respectively, for 19.2%, 4.9%, 4.2% of the GDS variability, cumulative responsible for 28.3% of GDS modifications. The present real-world study shows that CPAP treatment is able to improve cognition and depressive symptoms in OSAS elderly patients.

Evaluation of Lipid Extracts from the Marine Fungi Emericellopsis cladophorae and Zalerion maritima as a Source of Anti-Inflammatory, Antioxidant and Antibacterial Compounds

Marine environments occupy more than 70% of the earth's surface, integrating very diverse habitats with specific characteristics. This heterogeneity of environments is reflected in the biochemical composition of the organisms that inhabit them. Marine organisms are a source of bioactive compounds, being increasingly studied due to their health-beneficial properties, such as antioxidant, anti-inflammatory, antibacterial, antiviral, or anticancer. In the last decades, marine fungi have stood out for their potential to produce compounds with therapeutic properties. The objective of this study was to determine the fatty acid profile of isolates from the fungi Emericellopsis cladophorae and Zalerion maritima and assess the anti-inflammatory, antioxidant, and antibacterial potential of their lipid extracts. The analysis of the fatty acid profile, using GC-MS, showed that E. cladophorae and Z. maritima possess high contents of polyunsaturated fatty acids, 50% and 34%, respectively, including the omega-3 fatty acid 18:3 n-3. Emericellopsis cladophorae and Z. maritima lipid extracts showed anti-inflammatory activity expressed by the capacity of their COX-2 inhibition which was 92% and 88% of inhibition at 200 µg lipid mL^-1, respectively. Emericellopsis cladophorae lipid extracts showed a high percentage of inhibition of COX -2 activity even at low concentrations of lipids (54% of inhibition using 20 µg lipid mL^-1), while a dose-dependent behaviour was observed in Z. maritima. The antioxidant activity assays of total lipid extracts demonstrated that the lipid extract from E. cladophorae did not show antioxidant activity, while Z. maritima gave an IC₂₀ value of 116.6 ± 6.2 µg mL^-1 equivalent to 92.1 ± 4.8 µmol Trolox g^-1 of lipid extract in the DPPH• assay, and 101.3 ± 14.4 µg mL^-1 equivalent to 106.6 ± 14.8 µmol Trolox g^-1 of lipid extract in the ABTS•⁺ assay. The lipid extract of both fungal species did not show antibacterial properties at the concentrations tested. This study is the first step in the biochemical characterization of these marine organisms and demonstrates the bioactive potential of lipid extracts from marine fungi for biotechnological applications.

Anti-Inflammatory, Antioxidant, and Neuroprotective Effects of Polyphenols-Polyphenols as an Element of Diet Therapy in Depressive Disorders

Depressive disorders can affect up to 350 million people worldwide, and in developed countries, the percentage of patients with depressive disorders may be as high as 10%. During depression, activation of pro-inflammatory pathways, mitochondrial dysfunction, increased markers of oxidative stress, and a reduction in the antioxidant effectiveness of the body are observed. It is estimated that approximately 30% of depressed patients do not respond to traditional pharmacological treatments. However, more and more attention is being paid to the influence of active ingredients in food on the course and risk of neurological disorders, including depression. The possibility of using foods containing polyphenols as an element of diet therapy in depression was analyzed in the review. The possibility of whether the consumption of products such as polyphenols could alleviate the course of depression or prevent the progression of it was also considered. Results from preclinical studies demonstrate the potential of phenolic compounds have the potential to reduce depressive behaviors by regulating factors related to oxidative stress, neuroinflammation, and modulation of the intestinal microbiota.

Anti-inflammatory properties of commonly used psychiatric drugs

Mental health and neurodevelopmental disorders are extremely common across the lifespan and are characterized by a complicated range of symptoms that affect wellbeing. There are relatively few drugs available that target disease mechanisms for any of these disorders. Instead, therapeutics are focused on symptoms and syndromes, largely driven by neurotransmitter hypotheses, such as serotonin or dopamine hypotheses of depression. Emerging evidence suggests that maternal inflammation during pregnancy plays a key role in neurodevelopmental disorders, and inflammation can influence mental health expression across the lifespan. It is now recognized that commonly used psychiatric drugs (anti-depressants, anti-psychotics, and mood stabilizers) have anti-inflammatory properties. In this review, we bring together the human evidence regarding the anti-inflammatory mechanisms for these main classes of psychiatric drugs across a broad range of mental health disorders. All three classes of drugs showed evidence of decreasing levels of pro-inflammatory cytokines, particularly IL-6 and TNF-α, while increasing the levels of the anti-inflammatory cytokine, IL-10. Some studies also showed evidence of reduced inflammatory signaling via nuclear factor- (NF-)κB and signal transducer and activator of transcription (STAT) pathways. As researchers, clinicians, and patients become increasingly aware of the role of inflammation in brain health, it is reassuring that these psychiatric drugs may also abrogate this inflammation, in addition to their effects on neurotransmission. Further studies are required to determine whether inflammation is a driver of disease pathogenesis, and therefore should be a therapeutic target in future clinical trials.

How Oxidative Stress Induces Depression?

Depression increasingly affects a wide range and a large number of people worldwide, both physically and psychologically, which makes it a social problem requiring prompt attention and management. Accumulating clinical and animal studies have provided us with substantial insights of disease pathogenesis, especially central monoamine deficiency, which considerably promotes antidepressant research and clinical treatment. The first-line antidepressants mainly target the monoamine system, whose drawbacks mainly include slow action and treatment resistant. The novel antidepressant esketamine, targeting on central glutamatergic system, rapidly and robustly alleviates depression (including treatment-resistant depression), whose efficiency is shadowed by potential addictive and psychotomimetic side effects. Thus, exploring novel depression pathogenesis is necessary, for seeking more safe and effective therapeutic methods. Emerging evidence has revealed vital involvement of oxidative stress (OS) in depression, which inspires us to pursue antioxidant pathway for depression prevention and treatment. Fully uncovering the underlying mechanisms of OS-induced depression is the first step towards the avenue, thus we summarize and expound possible downstream pathways of OS, including mitochondrial impairment and related ATP deficiency, neuroinflammation, central glutamate excitotoxicity, brain-derived neurotrophic factor/tyrosine receptor kinase B dysfunction and serotonin deficiency, the microbiota-gut-brain axis disturbance and hypothalamic-pituitary-adrenocortical axis dysregulation. We also elaborate on the intricate interactions between the multiple aspects, and molecular mechanisms mediating the interplay. Through reviewing the related research progress in the field, we hope to depict an integral overview of how OS induces depression, in order to provide fresh ideas and novel targets for the final goal of efficient treatment of the disease.

How does IL-6 change after combined treatment in MDD patients? A systematic review

A growing amount of research suggests that inflammatory responses have a crucial role in the complex pathophysiology of Major Depressive Disorder (MDD), a disabling medical condition. The present review has two primary goals. Firstly, to highlight and summarize results from studies that investigated the changes of IL-6 in MDD patients before and after combined treatment. The second aim is to enlighten the need for further research on the difference in the concentration of the pro-inflammatory cytokines between MDD and Treatment-Resistant MDD. The protocol of this study was written using PRISMA, and it is registered at PROSPERO (identification: CRD42021289233). We searched the following bibliographic databases to identify potentially eligible articles without any time limit until September 2021: Pubmed, Web of Science, Scopus, PsycINFO. As they met the eligibility criteria, 14 articles were included in this systematic review. The selected studies assessed twelve different elements as an adjunction to the standard pharmacotherapy (ECT, Ketamine, CBT, NCT, Ketoprofene, Lithium, Celecoxib, Metformin tDCS, Pentoxifylline, ethyl-EPA, Zinc). Significant results were found in the studies that analyzed the impact of combined treatment with the adjunction of the following elements: ECT, Ketamine, CBT, NCT, Celecoxib, Metformin, and Pentoxifylline. Overall, this systematic review identifies several potentially beneficial combined treatments for MDD patients. Further evidence is needed to confirm the efficacy of reducing IL-6 levels in patients with Treatment-Resistant MDD.

Antidepressant and Anxiolytic Effects of Fermented Huauzontle, a Prehispanic Mexican Pseudocereal

This study aimed to assess the potential antidepressant- and anxiolytic-like effects of huauzontle fermented by Lactiplantibacillus plantarum Lp22. The possible association between oxidative stress/inflammation biomarkers and unconditional behavioural tests was also evaluated. Red light-induced stress mice C57Bl/6 (n = 5 per group) received orally either fermented or unfermented huauzontle, diazepam or fluoxetine. A non-stressed group which received saline solution was also included. Then, anxiety-related and depression-related behaviour tests were performed; after that, blood and tissues samples were collected to determine oxidative stress/inflammation biomarkers. The mice receiving both fermented and unfermented huauzontle spent more time (94 s) in open arms in the elevated plus maze test p < 0.05; besides, travelled longer distance (p < 0.05) and increased by more than 50% the exploration time for the open field, as well as the time spent in the illuminated zone (197 s) in the light/dark test. Furthermore, reduced immobility time in the tail suspension and forced swim tests (23.1 and 15.85, respectively), and anhedonia was no detected in the sucrose preference test. The oxidative stress index was lower in the liver of fermented huauzontle-treated mice, while enhanced levels of IL-10, MCP-1 and BDNF in plasma, and lipoxygenase (LOX) activity in the hippocampus were found. Finally, PCA revealed a positive correlation among LOX and BDNF and parameters determined in the anxiety tests, as between catalase activity and immobility time in the depression test. These findings indicate the novel potential therapeutic applications of fermented huauzontle on depression and anxiety-like behaviours possibly mediated by antioxidant and anti-inflammatory mechanisms.

Associations between air pollution and multimorbidity in the UK Biobank: A cross-sectional study

Background

Long-term exposure to air pollution concentrations is known to be adversely associated with a broad range of single non-communicable diseases, but its role in multimorbidity has not been investigated in the UK. We aimed to assess associations between long-term air pollution exposure and multimorbidity status, severity, and patterns using the UK Biobank cohort.

Methods

Multimorbidity status was calculated based on 41 physical and mental conditions. We assessed cross-sectional associations between annual modeled particulate matter (PM)2.5, PMcoarse, PM10, and nitrogen dioxide (NO2) concentrations (μg/m3-modeled to residential address) and multimorbidity status at the baseline assessment (2006-2010) in 364,144 people (mean age: 52.2 ± 8.1 years, 52.6% female). Air pollutants were categorized into quartiles to assess dose-response associations. Among those with multimorbidity (≥2 conditions; n = 156,395) we assessed associations between air pollutant exposure levels and multimorbidity severity and multimorbidity patterns, which were identified using exploratory factor analysis. Associations were explored using generalized linear models adjusted for sociodemographic, behavioral, and environmental indicators.

Results

Higher exposures to PM2.5, and NO2 were associated with multimorbidity status in a dose-dependent manner. These associations were strongest when we compared the highest air pollution quartile (quartile 4: Q4) with the lowest quartile (Q1) [PM2.5: adjusted odds ratio (adjOR) = 1.21 (95% CI = 1.18, 1.24); NO2: adjOR = 1.19 (95 % CI = 1.16, 1.23)]. We also observed dose-response associations between air pollutant exposures and multimorbidity severity scores. We identified 11 multimorbidity patterns. Air pollution was associated with several multimorbidity patterns with strongest associations (Q4 vs. Q1) observed for neurological (stroke, epilepsy, alcohol/substance dependency) [PM2.5: adjOR = 1.31 (95% CI = 1.14, 1.51); NO2: adjOR = 1.33 (95% CI = 1.11, 1.60)] and respiratory patterns (COPD, asthma) [PM2.5: adjOR = 1.24 (95% CI = 1.16, 1.33); NO2: adjOR = 1.26 (95% CI = 1.15, 1.38)].

Conclusions

This cross-sectional study provides evidence that exposure to air pollution might be associated with having multimorbid, multi-organ conditions. Longitudinal studies are needed to further explore these associations.

Nrf2: An all-rounder in depression

The balance between oxidation and antioxidant is crucial for maintaining homeostasis. Once disrupted, it can lead to various pathological outcomes and diseases, such as depression. Oxidative stress can result in or aggravate a battery of pathological processes including mitochondrial dysfunction, neuroinflammation, autophagical disorder and ferroptosis, which have been found to be involved in the development of depression. Inhibition of oxidative stress and related pathological processes can help improve depression. In this regard, the nuclear factor erythroid 2-related factor 2 (Nrf2) in the antioxidant defense system may play a pivotal role. Nrf2 activation can not only regulate the expression of a series of antioxidant genes that reduce oxidative stress and its damages, but also directly regulate the genes related to the above pathological processes to combat the corresponding alterations. Therefore, targeting Nrf2 has great potential for the treatment of depression. Activation of Nrf2 has antidepressant effect, but the specific mechanism remains to be elucidated. This article reviews the key role of Nrf2 in depression, focusing on the possible mechanisms of Nrf2 regulating oxidative stress and related pathological processes in depression treatment. Meanwhile, we summarize some natural and synthetic compounds targeting Nrf2 in depression therapy. All the above may provide new insights into targeting Nrf2 for the treatment of depression and provide a broad basis for clinical transformation.

Glymphatic Dysfunction Induced Oxidative Stress and Neuro-Inflammation in Major Depression Disorders

Major Depression disorder (MDD) is a potentially life-threatening mental illness, however, many patients have a poor response to current treatments. Recent studies have suggested that stress- or trauma-induced oxidative stress and inflammation could be important factors involved in the development of MDD, but the mechanisms remain unclear. We showed that the glymphatic system is a recently discovered structure in the brain that may be involved in the clearance of large molecular and cell debris in extracellular space. In addition, the glymphatic system can help with the removal of reactive oxygen species (ROS) and cytokines such as IL-1β and HIF-1α. Glymphatic impairment can lead to ROS accumulation in the microenvironment, inducing cellular injury signaling and activating NLRP3 in microglia to induce inflammation and, thus, many brain diseases, including psychiatric disorders. Therefore, trauma-induced glymphatic impairment could induce oxidative stress and inflammation, and thus MDD. This paper will review recent advances with regard to stress-induced glymphatic system impairment and ROS-mediated inflammation in MDD.

Plasma levels of interleukin-8 and response to paroxetine in patients with major depressive disorder

OBJECTIVES

Immune dysregulation plays a key role in major depressive disorder (MDD). However, little is known about the complicated involvement of various interleukins in MDD. This study was performed to investigate the correlation between plasma interleukin-8 (IL-8) levels and treatment outcome of paroxetine (a selective serotonin reuptake inhibitor) in patients with MDD.

METHODS

A total of 115 hospitalized patients (36 males and 79 females), aged from 18 to 72 years, were enrolled. Plasma levels of IL-8 were measured before treatment initiation (baseline) and at 8 weeks after oral paroxetine treatment. Efficacy of paroxetine was evaluated by use of the Hamilton Depression Rating Scale (HAMD-17). Baseline IL-8 levels were compared between responders and non-responders to paroxetine treatment.

RESULTS

Plasma IL-8 levels decreased significantly after an 8-week antidepressant treatment in responders, in association with a dramatic decrease in HAMD-17 scores. In non-responders, plasma IL-8 levels did not change significantly at 8 weeks after antidepressant treatment. Baseline plasma IL-8 levels were found to be significantly lower in responders than in non-responders, showing a correlation between IL-8 and antidepressant response to paroxetine.

CONCLUSIONS

These results indicate that plasma IL-8 levels were related to treatment outcome of paroxetine, and therefore suggest that IL-8 could be a promising predicator of treatment response in individual patients with MDD.

Behavioral alterations, brain oxidative stress, and elevated levels of corticosterone associated with a pressure injury model in male mice

OBJECTIVES

Sustained stress can cause physiological disruption in crucial systems like the endocrine, autonomic, and central nervous system. In general, skin damages are physical stress present in hospitalized patients. Also, these pressure injuries lead to pathophysiological mechanisms involved in the neurobiology of mood disorders. Here, we aimed to investigate the behavioral alterations, oxidative stress, and corticosterone levels in the brain areas of mice submitted to the model of pressure injury (PI).

METHODS

The male mice behaviors were assessed in the open field test (OFT), elevated plus maze test (EPM), tail suspension test (TST), and sucrose preference test (SPT). Then, we isolated the prefrontal cortex (PFC), hippocampus (HP), and striatum (ST) by brain dissection. The nonprotein sulfhydryl groups (NP-SH) and malondialdehyde (MDA) were measured in the brain, and also the plasma corticosterone levels were verified.

RESULTS

PI model decreased the locomotor activity of animals (p<0.05). Considering the EPM test, the PI group showed a decrease in the open arm activity (p<0.01), and an increase in the closed arm activity (p<0.05). PI group showed an increment in the immobility time (p<0.001), and reduced sucrose consumption (p<0.0001) compared to the control groups. Regarding the oxidative/nitrosative profile, all brain areas from the PI group exhibited a reduction in the NP-SH levels (p<0.0001-p<0.01), and an increase in the MDA level (p<0.001-p<0.01). Moreover, the PI male mice presented increased levels of plasma corticosterone (p<0.05).

CONCLUSIONS

Our findings suggest that the PI model induces depressive and anxiety-like behaviors. Furthermore, it induces pathophysiological mechanisms like the neurobiology of depression.

Ameliorating potential of curcumin and its analogue in central nervous system disorders and related conditions: A review of molecular pathways

Curcumin, isolated from turmeric (Curcuma longa L.) is one of the broadly studied phytomolecule owing to its strong antioxidant and anti-inflammatory potential and has been considered a promising therapeutic candidate in a wide range of disorders. Considering, its low bioavailability, different curcumin analogs have been developed to afford desired pharmacokinetic profile and therapeutic outcome in varied pathological states. Several preclinical and clinical studies have indicated that curcumin ameliorates mitochondrial dysfunction, inflammation, oxidative stress apoptosis-mediated neural cell degeneration and could effectively be utilized in the treatment of different neurodegenerative diseases. Hence, in this review, we have summarized key findings of experimental and clinical studies conducted on curcumin and its analogues with special emphasis on molecular pathways, viz. NF-kB, Nrf2-ARE, glial activation, apoptosis, angiogenesis, SOCS/JAK/STAT, PI3K/Akt, ERK1/2 /MyD88 /p38 MAPK, JNK, iNOS/NO, and MMP pathways involved in imparting ameliorative effects in the therapy of neurodegenerative disorders and associated conditions.

Indole-3-Carbinol (I3C) Protects the Heart From Ischemia/Reperfusion Injury by Inhibiting Oxidative Stress, Inflammation, and Cellular Apoptosis in Mice

Strategies for treating myocardial ischemia in the clinic usually include re-canalization of the coronary arteries to restore blood supply to the myocardium. However, myocardial reperfusion insult often leads to oxidative stress and inflammation, which in turn leads to apoptosis and necrosis of myocardial cells, for which there are no standard treatment methods. The aim of this study was to determine the pharmacological effect of indole-3-carbinol (I3C), a phytochemical found in most cruciferous vegetables, in a mouse model of myocardial ischemia/reperfusion injury (MIRI). Our results showed that I3C pretreatment (100 mg/kg, once daily, i. p.) prevented the MIRI-induced increase in infarct size and serum creatine kinase (CK) and lactate dehydrogenase (LDH) in mice. I3C pretreatment also suppressed cardiac apoptosis in MIRI mice by increasing the expression levels of the anti-apoptotic protein Bcl-2 and decreasing the expression levels of several apoptotic proteins, including Bax, caspase-3, and caspase-9. In addition, I3C pretreatment was found to reduce the levels of parameters reflecting oxidative stress, such as dihydroethidium (DHE), malondialdehyde (MDA), reactive oxygen species (ROS), and nitric oxide (NO), while increasing the levels of parameters reflecting anti-oxidation, such as total antioxidant capacity (T-AOC) and glutathione (GSH), in MIRI-induced ischemic heart tissue. I3C pretreatment was also able to remarkably decrease the expression of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) mRNA in ischemic heart tissue. These results demonstrate that administration of I3C protects the heart from MIRI through its anti-apoptotic, antioxidant, and anti-inflammatory effects.

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

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

(E)-1-(3-Benzoyl-4-phenyl-1H-pyrrol-1-yl)-3-phenylprop-2-en-1-one

Over the last decade, there has been an increasing effort to fight inflammatory conditions establishing new multitarget approaches. Chronic inflammation is implicated in many multifactorial diseases, constituting a great economic burden and a chronic health problem. In an attempt to develop new potent multifunctional anti-inflammatory agents, a cinnamic-pyrrole hybrid (6) was synthesized and screened for its antioxidant and anti-Lipoxygenase potential. The new compound, in comparison with its pyrrole precursor (4), showed improved biological activities. In silico calculations were performed to predict its drug-likeness. The examined derivative is considered orally bioavailable according to Lipinski’s rule of five. Compound 6 could be used as a lead for the synthesis of more effective hybrids.

Potential Mechanisms and Clinical Effectiveness of Acupuncture in Depression

Major depressive disorder is the most common mental disorder with significant economic burden and limited treatments. Acupuncture has emerged as a promising non-pharmacological treatment for reducing depressive symptoms. However, the potential mechanisms and clinical effectiveness of acupuncture are not fully understood. This review aimed to: (1) summarize the available evidence on the mechanisms and clinical effectiveness of acupuncture for depression, and then (2) compare with pharmacological interventions, guiding future studies. Studies with animal models of depression and patients have shown that acupuncture could increase hippocampal and network neuroplasticity and decrease brain inflammation, potentially to alleviating depressive disorders. Overall clinical studies indicated that acupuncture could relieve primary depression, particularly milder cases, and was helpful in the management of post-stroke depression, pain-related depression, and postpartum depression both as an isolated and adjunct treatment. It was emphasized that acupuncture combined with antidepressant pharmacological treatment not only enhanced the improvement of primary and secondary depressive symptoms but also reduced the side effects of the medical treatment, which is the main cause for high dropout rates with drug treatment. In summary, substantial evidence from animal and human researches supported the beneficial effect of acupuncture in depression. However, most clinical trials of acupuncture were small, and it is unclear whether their findings can be generalized, so more studies are needed.

Association between air pollution exposure and mental health service use among individuals with first presentations of psychotic and mood disorders: retrospective cohort study

BACKGROUND

Growing evidence suggests that air pollution exposure may adversely affect the brain and increase risk for psychiatric disorders such as schizophrenia and depression. However, little is known about the potential role of air pollution in severity and relapse following illness onset.

AIMS

To examine the longitudinal association between residential air pollution exposure and mental health service use (an indicator of illness severity and relapse) among individuals with first presentations of psychotic and mood disorders.

METHOD

We identified individuals aged ≥15 years who had first contact with the South London and Maudsley NHS Foundation Trust for psychotic and mood disorders in 2008-2012 (n = 13 887). High-resolution (20 × 20 m) estimates of nitrogen dioxide (NO2), nitrogen oxides (NOx) and particulate matter (PM2.5 and PM10) levels in ambient air were linked to residential addresses. In-patient days and community mental health service (CMHS) events were recorded over 1-year and 7-year follow-up periods.

RESULTS

Following covariate adjustment, interquartile range increases in NO2, NOx and PM2.5 were associated with 18% (95% CI 5-34%), 18% (95% CI 5-34%) and 11% (95% CI 3-19%) increased risk for in-patient days after 1 year. Similarly, interquartile range increases in NO2, NOx, PM2.5 and PM10 were associated with 32% (95% CI 25-38%), 31% (95% CI 24-37%), 7% (95% CI 4-11%) and 9% (95% CI 5-14%) increased risk for CMHS events after 1 year. Associations persisted after 7 years.

CONCLUSIONS

Residential air pollution exposure is associated with increased mental health service use among people recently diagnosed with psychotic and mood disorders. Assuming causality, interventions to reduce air pollution exposure could improve mental health prognoses and reduce healthcare costs.

Lycopene and Chrysin through Mitigation of Neuroinflammation and Oxidative Stress Exerted Antidepressant Effects in Clonidine-Induced Depression-like Behavior in Rats

Depression is a severely debilitating psychiatric disorder that influences more than 15% of the population worldwide. It has been demonstrated that it is associated with a high risk of developing other diseases such as cardiovascular diseases, diabetes, stroke, epilepsy, and cancer. The current study examines the possibility of chrysin and lycopene having an antidepressant effect in a rat model of depression induced by clonidine, as well as the mechanisms underlying this effect, including the role of neuroinflammation and oxidative stress. Rats were allotted into seven groups. The rats in group 1 served as a control. Group 2 received lycopene only. Group 3 was provided chrysin only. Group 4 was administered clonidine and served as the model. Group 5 was offered lycopene and clonidine. Group 6 was administered chrysin and clonidine. Group 7 was given FLX and clonidine and represented the standard. The experiment lasted two weeks, during which behavioral, biochemical, histopathological, and immunohistochemical measurements were performed. Lycopene and chrysin were used to correct the concentrations of noradrenaline and serotonin hippocampal tissue concentrations. These findings were also improved by immunohistochemical analysis of GFAP, VEGF, caspase3, and histopathological examinations, in which pretreatment of rats with lycopene and chrysin reversed all clonidine-induced alterations. The current research demonstrates that lycopene and chrysin have an auspicious antidepressant effect against clonidine that provoked behavioral hopelessness in rats. Manipulating oxidative stress, inflammation, and apoptosis may partially represent the corrective mechanism for the neuroprotective actions against the depressive effect of clonidine.

Quercitrin Rapidly Alleviated Depression-like Behaviors in Lipopolysaccharide-Treated Mice: The Involvement of PI3K/AKT/NF-κB Signaling Suppression and CREB/BDNF Signaling Restoration in the Hippocampus

Quercitrin (Qc) is a well-known flavonoid compound that exerts anti-inflammation effects on various diseases. The present study aimed to investigate the antidepressant-like response of Qc and its underlying mechanisms concerning neuroinflammation and neuroplasticity in mice with lipopolysaccharide (LPS)-induced depression-like behaviors. The results showed a single dose of Qc (10 mg/kg) produced an antidepressant-like effect at 2 h postadministration and lasted for at least 3 days. The expressions of neuroplasticity signaling molecules of pCREB/BDNF/PSD95/Synapsin1 were upregulated at 2 h, and ERK signaling was upregulated for 3 days in the hippocampus after a single administration of Oc or ketamine. A 5-day treatment of LPS led to depression-like behaviors, including reduced sucrose preference and increased immobility in the tail suspension test or forced swim test, which were all reversed by a single dose of Qc. In LPS-treated mice, Qc reduced the levels of inflammation-related factors including IL-10, IL-1β, and TNF-α in serum, as well as the activations of PI3K/AKT/NF-κB and MEK/ERK pathways in the hippocampus. Moreover, Qc restored the expressions of pCREB/BDNF/PSD95/Synapsin1 signaling in the hippocampus that were impaired by LPS. LY294002, a PI3K inhibitor, but not PD98059, a MEK inhibitor, produced effects similar to Qc. LY294002 also restored the expressions of pCREB/BDNF/PSD95/Synapsin1 signaling in the hippocampus impaired by LPS. Additionally, subeffective doses of Qc and LY294002 induced behavioral and molecular synergism. Together, the depression-like behaviors in LPS-treated mice were alleviated by a single dose of Qc likely via inhibition of the activations PI3K/AKT/NF-κB inflammation signaling and subsequent improvement of neuroplasticity.

Suppression of cigarette smoke induced MMP1 expression by selective serotonin re-uptake inhibitors

Globally, COPD remains a major cause of disability and death. In the United States alone, it is estimated that approximately 14 million people suffer from the disease. Given the high disease burden and requirement for chronic, long‐term medical care associated with COPD, it is essential that new disease modifying agents are developed to complement the symptomatic therapeutics currently available. In the present report, we have identified a potentially novel therapeutic agent through the use of a high throughput screen based on the knowledge that cigarette smoke induces the proteolytic enzyme MMP1 leading to destruction of the lung in COPD. A construct utilizing the cigarette responsive promoter element of MMP‐1 was conjugated to a luciferase reporter and utilized in an in vitro assay to screen the NIH Molecular Libraries Small Molecule Repository to identify putative targets that suppressed luciferase expression in response to cigarette smoke extract (CSE). Selective serotonin reuptake inhibitors potently inhibited luciferase expression and were further validated. SSRI treatment suppressed MMP‐1 production in small airway epithelial cells exposed to (CSE) in vitro as well as in smoke exposed rabbits. In addition, SSRI treatment inhibited inflammatory cytokine production while rescuing cigarette smoke induced downregulation in vivo of the anti‐inflammatory lipid transporter ABCA1, previously shown by our laboratory to be lung protective. Importantly, SSRI treatment prevented lung destruction in smoke exposed rabbits as measured by morphometry. These studies support further investigation into SSRIs as a novel therapeutic for COPD may be warranted.

Polygonatum sibiricum polysaccharide prevents depression-like behaviors by reducing oxidative stress, inflammation, and cellular and synaptic damage

ETHNOPHARMACOLOGICAL RELEVANCE

According to traditional Chinese medicine (TCM) theory (Yi Xue Zheng Zhuan), the main factors associated with the pathogenesis of depression are deficiencies relating to five zang organs, Qi, and blood. Polygonatum sibiricum F. Delaroche (PS), which may avert these pathological changes, has been used in a variety of formulas to treat depression. However, the effects and mechanism of action of PS, alone, and especially those of its main active component PS polysaccharide (PSP), on depression remain unexplored.

AIM OF THE STUDY

To determine the effects of PSP on depression-like behaviors and to elucidate its mechanism of action.

METHODS

PSP was isolated from dried PS rhizomes and qualified using transmission electron microscopy and Fourier transform infrared spectroscopy. Lipopolysaccharide (LPS) and chronic unpredictable mild stress (CUMS)-induced depression models were used to evaluate the antidepressive effects of PSP. Veinal blood and brain tissue were collected to determine the levels of hippocampal 5-HT, serum cortisol (CORT), brain and serum cytokines, and hippocampal oxidation-related indicators. The protein expression levels of phosphorylated extracellular signal-regulated kinase (p-ERK1/2), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), glial fibrillary acidic protein (GFAP), phosphorylated protein kinase B (p-Akt), phosphorylation of the mammalian target of rapamycin (mTOR), caspase-3, GluA1 and GluA2, and GluN2A and GluN2B were determined using western blotting and immunofluorescence. Nissl staining was performed to detect histopathological changes in brain tissues.

RESULTS

Injection of LPS (i.p.) induced depression-like behaviors, reduced the level of hippocampal 5-HT, increased the serum CORT level and hippocampal oxidative stress (ROS), and prompted the activation of ERK1/2, NF-κB, and GFAP and an inflammatory response. Conversely, PSP administration reduced these changes and prevented depression-like behaviors. PSP administration also promoted hippocampal expression of p-Akt, p-mTOR, GluA1, and GluA2; reduced the expression of caspase-3, GluN2A, and GluN2B; and prohibited the loss of granular cells in the DG region.

CONCLUSION

These results indicate that PSP prevents depression-like behaviors, and synaptic and neuronal damage probably by reducing ROS/HPA axis hyperfunction and the inflammatory response.

Association between chronic psychoactive substances use and systemic inflammation: A systematic review and meta-analysis

This systematic review and meta-analysis assess the change in inflammation biomarkers level among chronic psychoactive substance users. To meet the required inclusion criteria, all studies had to describe human participants with an age ≥18y., experiencing chronic psychostimulant (nicotine, amphetamine, cocaine), sedative (benzodiazepine, opioids) and/or cannabinoid use. The comparison group was defined as healthy participants. Studies where included if they reported at least one of the pro/inflammatory biomarkers. Study bias was examined by Funnel plots and heterogeneity by computing the I² statistics. Only 21 eligible studies were selected based on 26,216 study participants. A small and significant effect size of 0.18 mg/l (95 % CI:0.10-0.27) was detected in favour of chronic smokers (z = 4.33;P < 0.0001). There was evidence of publication bias for studies measuring IL-6 and IL-10 association with cocaine and IL-6 in association with cannabis. In summary, except for chronic tobacco users, there was no evidence of association between other chronic substances abuse and inflammatory levels. More studies are needed to inform policy and decision makers about the utility of anti-inflammatory based targeted intervention programmes.

Inflammatory Depression-Mechanisms and Non-Pharmacological Interventions

Treatment of depression is hampered by the failure to identify distinct symptom profiles with distinct pathophysiologies that differentially respond to distinct treatments. We posit that inflammatory depression is a meaningful depression subtype associated with specific symptoms and biological abnormalities. We review several upstream, potentially causative, mechanisms driving low-grade inflammation in this subtype of depression. We also discuss downstream mechanisms mediating the link between inflammation and symptoms of depression, including alterations in dopaminergic neurotransmission and tryptophan metabolism. Finally, we review evidence for several non-pharmacological interventions for inflammatory depression, including probiotics, omega-3 fatty acids, and physical exercise interventions. While some evidence suggests that these interventions may be efficacious in inflammatory depression, future clinical trials should consider enriching patient populations for inflammatory markers, or stratify patients by inflammatory status, to confirm or refute this hypothesis.

Antidepressant Effect of Paeoniflorin Is Through Inhibiting Pyroptosis CASP-11/GSDMD Pathway

Nod-like receptor protein 3 (NLRP3)-associated neuroinflammation mediated by activated microglia is involved in the pathogenesis of depression. The role of the pore-forming protein gasdermin D (GSDMD), a newly identified pyroptosis executioner downstream of NLRP3 inflammasome mediating inflammatory programmed cell death, in depression has not been well defined. Here, we provide evidence that paeoniflorin (PF), a monoterpene glycoside compound derived from Paeonia lactiflora, ameliorated reserpine-induced mouse depression-like behaviors, characterized as increased mobility time in tail suspension test and forced swimming test, as well as the abnormal alteration of synaptic plasticity in the depressive hippocampus. The molecular docking simulation predicted that PF would interact with C-terminus of GSDMD. We further demonstrated that PF administration inhibited the enhanced expression of GSDMD which mainly distributed in microglia, along with the proteins involved in pyroptosis signaling transduction including caspase (CASP)-11, CASP-1, NLRP3, and interleukin (IL)-1β in the hippocampus of mice treated with reserpine. And also, PF prevented lipopolysaccharide (LPS) and adenosine triphosphate (ATP)-induced pyroptosis in murine N9 microglia in vitro, evidenced by inhibiting the expression of CASP-11, NLRP3, CASP-1 cleavage, as well as IL-1β. Furthermore, VX-765, an effective and selective inhibitor for CASP-1 activation, reduced the expression of inflammasome and pyroptosis-associated proteins in over-activated N9 and also facilitated PF-mediated inhibition of pyroptosis synergistically. Collectively, the data indicated that PF exerted antidepressant effects, alleviating neuroinflammation through inhibiting CASP-11-dependent pyroptosis signaling transduction induced by over-activated microglia in the hippocampus of mice treated with reserpine. Thus, GSDMD-mediated pyroptosis in activated microglia is a previously unrecognized inflammatory mechanism of depression and represents a unique therapeutic opportunity for mitigating depression given PF administration.

Dietary inflammatory index (DII®) and the risk of depression symptoms in adults

BACKGROUND & AIMS

Findings from observational studies investigating the association between Dietary Inflammatory Index (DII®) scores and depression symptoms (DepS) are inconsistent. This study aims to assess the association between energy-adjusted DII (E-DII™) and DepS using the North West Adelaide Health Study (NWAHS) cohort as well as update a previous meta-analysis.

METHODS

A total of 1743 (mean ± SD age: 56.6 ± 13.6 years, 51% female) study participants from NWAHS were included in the cross-sectional study and 859 (mean ± SD age: 58.4 ± 12.1 years, 52.6% female) in the longitudinal analyses. The Center for Epidemiological Studies Depression Scale (CES-D) was used for the measurement of DepS. E-DII scores were calculated from the dietary data collected using a validated food frequency questionnaire (FFQ). Data from two stages [Stage 3 (2008-10) and North West 15 (NW15) (2015)] were used. Log- and negative binomial regression were used to assess the association between quartiles of E-DII and DepS. A recent meta-analysis was updated by including 12 publications (six cross-sectional and six cohort studies) on the association between DII and DepS.

RESULTS

In the cross-sectional analysis, a higher E-DII score (i.e., more pro-inflammatory diet) was associated with a 79% increase in odds of reporting DepS [OR_Quartile4vs1: 1.79; 95% CI: 1.14-2.81; p = 0.01; p for trend (p_trend) = 0.03]. Males with higher E-DII had a more than two-fold higher odds of DepS (OR_Quartile4vs1: 2.27; 95% CI: 1.02-5.06; p = 0.045; p_trend = 0.09). Females with higher E-DII had an 81% increase in odds of DepS (OR_Quartile4vs1: 1.81; 95% CI: 1.01-3.26; p = 0.046; p_trend = 0.07). These associations were consistent in the longitudinal analysis. Comparing highest to lowest quintiles of E-DII, the updated meta-analysis showed that a pro-inflammatory diet is associated with a 45% increase in odds of having DepS (OR: 1.45; 95% CI: 1.20-1.74; p < 0.01) with higher odds in females (OR: 1.53; 95% CI: 1.16-2.01; p = 0.01) compared to their male counterparts (OR: 1.29; 95% CI: 0.98-1.69; p = 0.15).

CONCLUSION

The data from the NWAHS and the updated meta-analysis of observational studies provide further evidence that a pro-inflammatory diet is positively associated with increased risk of DepS. These findings support the current recommendation on consuming a less inflammatory diet to improve DepS.

Vitamin E for the management of major depressive disorder: possible role of the anti-inflammatory and antioxidant systems

OBJECTIVES

Vitamin E has various functions in humans, including antioxidant, anti-inflammatory, anti-cancer, and anti-atherogenic actions, as well as direct effects on enzymatic activities and modulation of gene transcription. In addition to these functions, vitamin E is also important for the central nervous system, and its role in the prevention and/or treatment of some neurological diseases has been suggested. In particular, the role of vitamin E in the modulation of major depressive disorder (MDD) is an issue that has emerged in recent studies. Many factors have been implicated in the pathophysiology of this disorder, including inflammation, oxidative, and nitrosative stress.

METHODS

This narrative review discusses the involvement of inflammation, oxidative, and nitrosative stress in the pathophysiology of MDD and presents clinical and preclinical studies that correlate vitamin E with this psychiatric disorder.

RESULTS

We gathered evidence from clinical studies that demonstrated the relationship between low vitamin E status and MDD symptoms. Vitamin E has been reported to exert a beneficial influence on the oxidative and inflammatory status of individuals, factors that may account for the attenuation of depressive symptoms. Preclinical studies have reinforced the antidepressant-like response of vitamin E, and the mechanisms underlying its effect seem to be related to the modulation of oxidative stress and neuroinflammation.

CONCLUSION

We suggest that vitamin E has potential to be used as an adjuvant for the management of MDD, but more studies are clearly needed to ascertain the efficacy of vitamin E for alleviating depressive symptoms.

Dietary antioxidants and fibre intake and depressive symptoms in Iranian adolescent girls

OBJECTIVE

To investigate the cross-sectional association between dietary intakes of antioxidants and fibre and depressive symptoms among Iranian adolescent girls.

DESIGN

A cross-sectional population-based study.

SETTING

Primary schools in two different cities located in northeastern Iran (Mashhad and Sabzevar).

PARTICIPANTS

A total of 988 adolescent girls aged 12-18 years were included in the study.

RESULTS

Subjects with no or minimal depression symptoms had significantly higher dietary intakes of α-carotene (P = 0·01), β-carotene (P = 0·006), lutein (P = 0·03) and vitamin C (P = 0·04) when compared with subjects with mild-to-severe depression symptoms. Soluble dietary fibre and insoluble dietary fibre intakes were also significantly higher in healthy adolescents compared with those with depression symptoms (P < 0·001). In multivariate-adjusted model 2, the OR (95 % CI) of depressive symptoms were 0·61 (95 % CI 0·37, 1·01), 0·42 (95 % CI 0·26, 0·69), 0·50 (95 % CI 0·31, 0·79), 0·71 (95 % CI 0·44, 1·15), 0·51 (95 % CI 0·32, 0·82) and 0·42 (95 % CI 0·25, 0·68) for the highest v. lowest quartile of vitamin C, β-carotene, α-carotene, lutein, soluble dietary fibre and insoluble dietary fibre cereal intakes, respectively.

CONCLUSIONS

Dietary intake of some antioxidants and dietary fibre intake was inversely associated with depression symptoms among Iranian adolescent girls.

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.

Neonatal Immune Activation May Provoke Long-term Depressive Attributes

BACKGROUND

Studies have shown the relationship between neuroinflammation and depressive- like parameters. However, research still has not been carried out to evaluate neuroinflammation in the neonatal period and psychiatric disorders in adulthood.

OBJECTIVE

To verify the association between neonatal immune activation and depressive-like parameters in adulthood using an animal model.

METHODS

Two days old C57BL/6 animals were exposed to lipopolysaccharides (LPS) or phosphate- buffered saline (PBS). When the animals were 46 days old, they received PBS or Imipramine at 14 days. At 60 days, the consumption of sucrose; immobility time; adrenal gland and the hippocampus weight; levels of plasma corticosterone and hippocampal Brain-derived neurotrophic factor (BDNF) were evaluated.

RESULTS

It was observed that the animals exposed to LPS in the neonatal period and evaluated in adulthood decreased the consumption of sucrose and had reducted hippocampus weight. Also, the exposed animals presented an increase of immobility time, adrenal gland weight and plasma levels of corticosteroids. The use of imipramine did not only modify the decreased hippocampal weight. On the other hand, there were no alterations in the BDNF levels in the hippocampus with or without the use of imipramine.

CONCLUSION

These results suggest that neonatal immune activation may be associated with depressive- like parameters in adulthood. It is believed that endotoxemia may trigger physiological and behavioral alterations, increasing vulnerability for the development of depression in adulthood.

Dietary Interventions in the Management of Fibromyalgia: A Systematic Review and Best-Evidence Synthesis

Fibromyalgia syndrome (FMS) is characterised by chronic widespread pain alongside fatigue, poor sleep quality and numerous comorbidities. It is estimated to have a worldwide prevalence of 1.78%, with a predominance in females. Treatment interventions for fibromyalgia have limited success, leading to many patients seeking alternative forms of treatment, including modifications to their diet and lifestyle. The effectiveness of dietary changes in fibromyalgia has not been widely researched or evaluated. This systematic review identified twenty-two studies, including 18 randomised control trials (RCTs) and four cohort studies which were eligible for inclusion. In total these studies investigated 17 different nutritional interventions. Significant improvements in reported pain were observed for those following a vegan diet, as well as with the low fermentable oligo di-mono-saccharides and polyols (FODMAP) diets. Supplementation with Chlorella green algae, coenzyme Q10, acetyl-l-carnitine or a combination of vitamin C and E significantly improved measures of pain. Interpretation of these studies was limited due to the frequent poor quality of the study design, the wide heterogeneity between studies, the small sample size and a high degree of bias. Therefore, there is insufficient evidence to recommend any one particular nutritional intervention for the management of fibromyalgia and further research is needed.

Poria cocos water extract ameliorates the behavioral deficits induced by unpredictable chronic mild stress in rats by down-regulating inflammation

ETHNOPHARMACOLOGICAL RELEVANCE

Poria cocos is a medicinal mushroom of the Polyporaceae family with antioxidant and anti-inflammatory activities, which has been used for its sedative, diuretic and tonic effects in traditional medicine for several hundred years.

AIM OF STUDY

Considering that depression is an inflammatory related mental disease, this study investigated the antidepressant-like effects of water extract of P. cocos in a rodent animal model.

MATERIALS AND METHODS

Rats that were exposed to a forced swimming test (FST) for 28 consecutive days, and unpredictable chronic mild stress (UCMS) for five weeks underwent treatment with P. cocos water extract (PCW) (doses: 100, 300 and 900 mg/kg body weight [bw]; administered by gavage). Dopamine (DA), serotonin (5-HT) and their metabolites in the frontal cortex of rats were measured.

RESULTS

Our results firstly showed that sucrose preference during the UCMS paradigm was increased and immobility time in the FST was reduced with administration of PCW. In addition, PCW significantly attenuated UCMS-induced turnover rate of DA and 5-HT in the frontal cortex. Moreover, PCW inhibited UCMS-induced activated inflammatory response, reflected by reduced expression in the frontal cortex of p38, NF-κB and TNF-α.

CONCLUSIONS

Our results strongly suggest that PCW exhibits a potent antidepressant-like effect via regulation of monoaminergic neurotransmission and inactivation of inflammation, and that P. cocos may be considered as a traditional herbal potential medicine for the treatment of depression.

Antioxidant Potential of Psychotropic Drugs: From Clinical Evidence to In Vitro and In Vivo Assessment and toward a New Challenge for in Silico Molecular Design

Due to high oxygen consumption, the brain is particularly vulnerable to oxidative stress, which is considered an important element in the etiopathogenesis of several mental disorders, including schizophrenia, depression and dependencies. Despite the fact that it is not established yet whether oxidative stress is a cause or a consequence of clinic manifestations, the intake of antioxidant supplements in combination with the psychotropic therapy constitutes a valuable solution in patients' treatment. Anyway, some drugs possess antioxidant capacity themselves and this aspect is discussed in this review, focusing on antipsychotics and antidepressants. In the context of a collection of clinical observations, in vitro and in vivo results are critically reported, often highlighting controversial aspects. Finally, a new challenge is discussed, i.e., the possibility of assessing in silico the antioxidant potential of these drugs, exploiting computational chemistry methodologies and machine learning. Despite the physiological environment being incredibly complex and the detection of meaningful oxidative stress biomarkers being all but an easy task, a rigorous and systematic analysis of the structural and reactivity properties of antioxidant drugs seems to be a promising route to better interpret therapeutic outcomes and provide elements for the rational design of novel drugs.