Hypozincemia in depression

Serum Levels of Zinc, Albumin, Interleukin-6 and CRP in Patients with Unipolar and Bipolar Depression: Cross Sectional Study

Unipolar (UD) and bipolar depression (BDD) show a high degree of similarity in clinical presentations, which complicates the differential diagnosis of these disorders. The aim of this study was to investigate the serum levels of interleukin 6 (IL-6), C-reactive protein (CRP), albumin (Alb), and zinc (Zn) in patients with UD, BDD, and healthy controls (HC). A total of 211 samples were collected: 131 patient samples (65 UD and 68 BDD) and 80 HC. The Montgomery-Asberg Depression Rating Scale (MADRS), along with the Hamilton Depression Rating Scale (HAMD-17), were administered to patient groups to evaluate symptoms. A cross-sectional study was performed to analyse the serum levels of IL-6, CRP, albumin, and zinc. The concentration of CRP was determined using the immunoturbidimetry method, zinc using the colorimetric method, and albumin using the colorimetric method with bromocresol green on the Alinity c device. IL-6 cytokine concentration in serum samples was ascertained using a commercial enzyme immunoassay, ELISA. We found no significant differences in serum concentrations of zinc, albumin, CRP, and IL-6 between the groups of patients with unipolar and bipolar depression. There was a significant statistical difference (p < 0.001) between serum levels of all investigated parameters in both groups of depressed patients in comparison with HC. Furthermore, correlations with specific items on HAMD-17; (namely, hypochondrias, work and activities, somatic symptoms-general, and weight loss) and on MADRS (concentration difficulties, lassitude) were observed in both patient groups. These findings confirm the presence of low-grade inflammation in depression, thus adding better insight into the inflammation hypothesis directed to explain the aetiology of depressive disorders. Our results do not indicate potential biomarkers for distinguishing between unipolar and bipolar depression.

Association of healthy eating index (2015) with depression and anxiety symptoms among Iranian adolescent girls

Adolescence is a period of rapid growth, with changes in body composition and cognitive and psychosocial development. Teenagers who eat properly and participate in daily physical activities have a healthy lifestyle. Healthy living promotes optimal growth and performance at school and in the workplace and minimizes the risk of chronic nutrient-related diseases. Therefore, the present study was conducted to determine the relationship between the healthy eating index (2015) (HEI-2015) and depression and anxiety among Iranian adolescent girls. This cross-sectional study was designed based on the updated version of HEI-2015. The study population consisted of 412 high school girls aged 12-17 years old. Data were collected about the diet, sociodemographic, and anthropometric characteristics of the participants. HEI and anthropometric characteristics of the participants were measured. The depression, anxiety, and stress scale 42 (DASS-42) questionnaire was used to detect adolescents suffering from depression and anxiety. The relationships of the HEI and anthropometric measures with depression and anxiety were also assessed. The results showed that the HEI is inversely correlated with depression and anxiety in Iranian adolescent girls. HEI was greater in the healthy participants than in those suffering from depression and anxiety (P < 0.0001).

Neurodevelopmental Consequences of Dietary Zinc Deficiency: A Status Report

Zinc is a tightly regulated trace mineral element playing critical roles in growth, immunity, neurodevelopment, and synaptic and hormonal signaling. Although severe dietary zinc deficiency is relatively uncommon in the United States, dietary zinc deficiency is a substantial public health concern in low- and middle-income countries. Zinc status may be a key determinant of neurodevelopmental processes. Indeed, limited cohort studies have shown that serum zinc is lower in people diagnosed with autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), and depression. These observations have sparked multiple studies investigating the mechanisms underlying zinc status and neurodevelopmental outcomes. Animal models of perinatal and adult dietary zinc restriction yield distinct behavioral phenotypes reminiscent of features of ASD, ADHD, and depression, including increased anxiety and immobility, repetitive behaviors, and altered social behaviors. At the cellular and molecular level, zinc has demonstrated roles in neurogenesis, regulation of cellular redox status, transcription factor trafficking, synaptogenesis, and the regulation of synaptic architecture via the Shank family of scaffolding proteins. Although mechanistic questions remain, the current evidence suggests that zinc status is important for adequate neuronal development and may be a yet overlooked factor in the pathogenesis of several psychiatric conditions. This review aims to summarize current knowledge of the role of zinc in the neurophysiology of the perinatal period, the many cellular targets of zinc in the developing brain, and the potential consequences of alterations in zinc homeostasis in early life.

Differentiating melancholic and non-melancholic depression via biological markers: A review

OBJECTIVES

Melancholia is a severe form of depression that is typified by greater genetic and biological influence, distinct symptomatology, and preferential response to physical treatment. This paper sought to broadly overview potential biomarkers of melancholia to benefit differential diagnosis, clinical responses and treatment outcomes. Given nuances in distinguishing melancholia as its own condition from other depressive disorder, we emphasised studies directly comparing melancholic to non-melancholic depression.

METHODS

A comprehensive literature search was conducted. Key studies were identified and summarised qualitatively.

RESULTS

105 studies in total were identified. These studies covered a wide variety of biomarkers, and largely fell into three domains: endocrinological (especially cortisol levels, particularly in response to the dexamethasone suppression test), neurological, and immunological (particularly inflammatory markers). Less extensive evidence also exists for metabolic, genetic, and cardiovascular markers.

CONCLUSIONS

Definitive conclusions were predominantly limited due to substantial heterogeneity in how included studies defined melancholia. Furthermore, this heterogeneity could be responsible for the between- and within-group variability observed in the candidate biomarkers that were examined. Therefore, clarifying these definitional parameters may help identify underlying patterns in biomarker expression to improve diagnostic and therapeutic precision for the depressive disorders.

Zinc and Central Nervous System Disorders

Zinc (Zn²⁺) is the second most abundant necessary trace element in the human body, exerting a critical role in many physiological processes such as cellular proliferation, transcription, apoptosis, growth, immunity, and wound healing. It is an essential catalyst ion for many enzymes and transcription factors. The maintenance of Zn²⁺ homeostasis is essential for the central nervous system, in which Zn²⁺ is abundantly distributed and accumulates in presynaptic vesicles. Synaptic Zn²⁺ is necessary for neural transmission, playing a pivotal role in neurogenesis, cognition, memory, and learning. Emerging data suggest that disruption of Zn²⁺ homeostasis is associated with several central nervous system disorders including Alzheimer's disease, depression, Parkinson's disease, multiple sclerosis, schizophrenia, epilepsy, and traumatic brain injury. Here, we reviewed the correlation between Zn²⁺ and these central nervous system disorders. The potential mechanisms were also included. We hope that this review can provide new clues for the prevention and treatment of nervous system disorders.

In end-stage kidney disease, inflammation, erythron abnormalities and declined kidney function tests are accompanied by increased affective symptoms, chronic-fatigue, and fibromyalgia.. [DOI: 10.1101/2023.01.12.23284460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background

Numerous neuropsychiatric symptoms, including affective symptoms, chronic fatigue syndrome, and fibromyalgia symptoms, are present in patients with end-stage renal disease (ESRD). This study examines the relationship between neuropsychiatric symptoms and red blood cell (RBC) parameters, kidney function tests, zinc, C-reactive protein, and calcium levels in patients with ESRD.

Methods

The above biomarkers and the Beck-Depression Inventory, the Hamilton Anxiety Rating Scale, and the Fibro-Fatigue Rating Scale were measured in 70 patients with end-stage renal disease (ESRD) and 46 healthy controls.

Results

Increased scores of depressive, anxious, cognitive, and physiosomatic symptoms (including chronic fatigue, fibromyalgia, and autonomous symptoms) characterise ESRD. One latent vector could be extracted from these diverse symptom domains, which are, therefore, manifestations of a common core referred to as the physio-affective phenome. The combined effects of aberrations in red blood cells (RBC) (number of RBC, hematocrit, and haemoglobin), kidney function tests (glomerular filtration rate, ureum, creatinine, albumin, and total serum protein), C-reactive protein, zinc, and copper explained 85.0% of the variance in the physio-affective phenome. In addition, the effects of kidney function decline on the phenome were partially mediated by RBC aberrations and elevated copper, whereas the effects of dialysis frequency were entirely mediated by decreased zinc and elevated CRP.

Conclusions

Affective (depression and anxiety), cognitive, and physiosomatic symptoms due to ESRD are interrelated manifestations of the physio-affective phenome, which is driven by (in descending order of importance) kidney dysfunctions, erythron deficits, inflammation, elevated copper, and decreased zinc.

Dietary Zinc Intake Affects the Association Between Dietary Vitamin A and Depression: A Cross-Sectional Study

Introduction

Dietary vitamin A concentrations correlate with depression. Zinc has been reported to be associated with lower depression. In addition, zinc is an important cofactor in the activation of vitamin A. However, there are few studies investigating relationships between of dietary zinc intake, dietary vitamin A intake and depression.

Materials and Methods

The data for this study came from the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018 and involved 70,190 participants. We stratified participants by recommended dietary zinc intake (recommended dietary zinc intake for women: 8 mg/day, recommended dietary zinc intake for men: 11 mg/day). We further assessed the association between vitamin A and depression in participants with low and high zinc intake (interaction test) using univariate logistic regression of intake participants.

Result

In the female population we grouped the population into low and high zinc intake groups using the recommended dietary zinc intake of 8 (mg/day), with an increase in total vitamin A, the risk of depression was significantly lower in the low zinc intake group (OR: 0.85 95 CI: 0.76–0.96), while the risk of depression was increased in the high zinc intake group (OR: 1.05 95 CI: 0.95 to 1.17). Thus, in the female population, there was a significant interaction between insufficient vitamin an intake and depression (interaction likelihood ratio test of p = 0.011). In the male population we grouped the population by the recommended dietary zinc intake of 11(mg/day). Again, the population was divided into two groups with low and high zinc intake, however we did not find significant results for the interaction (p = 0.743 for the interaction likelihood ratio test).

Conclusion

Our findings suggest that zinc intake may influence the relationship between dietary vitamin A and depression. Of course, our findings require further randomized controlled trials to enhance the credibility.

Immunostimulant and Antidepressant Effect of Natural Compounds in the Management of Covid-19 Symptoms

In recent years, the use of natural compounds as adjuvant treatments and alternatives to traditional pharmacological therapies has become increasingly popular. These compounds have a wide range of biological effects, such as: antioxidant, anti-aging, hypocholesterolizing, hypoglycemic, antitumoral, antidepressant, anxiolytic activity, etc. Almost all of these compounds are easily available and are contained in different foods. At the end of 2019 the Coronavirus SARS-CoV-2 appeared in China and quickly spread throughout the world, causing a pandemic. The most common symptoms of this infection are dry cough, fever, dyspnea, and in severe cases bilateral interstitial pneumonia, with consequences that can lead to death. The nations, in trying to prevent the spread of infection, have imposed social distancing and lockdown measures on their citizens. This had a strong psychological-social impact, leading to phobic, anxious and depressive states. Pharmacological therapy could be accompanied by treatment with several natural compounds, such as vitamins, baicalein, zinc and essential oils. These compounds possess marked immunostimulant activity, strengthening the immune response and mitigating interactions between the virus and the host cell. They also have an antidepressant effect, acting on certain neurotransmitters.

Neuronal correlates underlying the role of the zinc sensing receptor (GPR39) in passive-coping behaviour

The Zn²⁺ receptor GPR39 is proposed to be involved in the pathophysiology of depression. GPR39 knockout (KO) animals show depressive- and anxiety-like behaviour, and resistance to conventional monoamine-based antidepressants. However, it is unclear as to which brain regions are involved in the pro-depressive phenotype of GPR39KO mice and the resistance to monoamine-targeting antidepressant treatment. Our current study confirmed previous results, showing that mice lacking GPR39 display enhanced passive coping-like behaviour compared with their wild-type controls. Furthermore, this study shows for the first time that GPR39KO displayed aberrant challenge-induced neuronal activity in key brain regions associated with passive coping behaviour. Imipramine induced only a marginal reduction in the enhanced passive coping behaviour in GPR39KO mice, which was associated with attenuation of the hyperactive prefrontal cortex. Similarly, the aberrant activity within the amygdalar subregions was normalized following imipramine treatment in the GPR39KO mice, indicating that imipramine mediates these effects independently of GPR39 in the prefrontal cortex and amygdala. However, imipramine failed to modulate the aberrant brain activity in other brain regions, such as the anterior CA3 and the dentate gyrus, in GPR39KO mice. Normalization of aberrant activity in these areas has been shown previously to accompany successful behavioural effects of antidepressants. Taken together, our data suggest that monoamine-based antidepressants such as imipramine exert their action via GPR39-dependent and -independent pathways. Failure to modulate passive-coping related aberrant activity in important brain areas of the depression circuitry is proposed to mediate/contribute to the greatly reduced antidepressant action of monoamine-based antidepressants in GPR39KO mice.

Zinc supplementation combined with antidepressant drugs for treatment of patients with depression: a systematic review and meta-analysis

CONTEXT

Zinc is an essential trace mineral required for the function of brain and neural structures. The role of zinc supplementation in the prevention and treatment of depression has been suggested in clinical studies that reported a reduction in depressive symptoms.

OBJECTIVE

The aim of this review was to determine whether zinc supplementation vs placebo can prevent or improve depressive symptoms in children, adolescents, or adults.

DATA SOURCES

Five electronic databases were searched, and studies published until September 2019 were included without language restriction.

STUDY SELECTION

Randomized, controlled, crossover trials that evaluated the effect of zinc supplementation vs a comparator for prevention or improvement of depressive symptoms in children, adolescents, or adults were eligible for inclusion.

DATA EXTRACTION

Two authors independently performed data extraction and risk-of-bias assessment.

RESULTS

The initial search identified 12 322 studies, 5 of which were eligible for meta-analysis. The standardized mean difference (SMD) showed an average reduction of 0.36 point (95%CI, -0.67 to -0.04) in the intervention group compared with the placebo group. Forstudies in which the mean age of participants was ≥ 40 years, the SMD was reduced by 0.61 point (95%CI, -1.12 to -0.09) in the intervention group vs the placebo group. The meta-analysis by sample size (< 60 individuals and  ≥ 60 individuals) did not show an effect of zinc supplementation in reducing depressive symptoms (SMD -0.28; 95%CI, -0.67 to -0.10; and SMD -0.52; 95%CI, -1.10 to 0.06).

CONCLUSION

Zinc supplementation may reduce depressive symptoms in individuals treated with antidepressant drugs for clinical depression.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number CRD42018081691.

The Way to a Human's Brain Goes Through Their Stomach: Dietary Factors in Major Depressive Disorder

Globally, more than 250 million people are affected by depression (major depressive disorder; MDD), a serious and debilitating mental disorder. Currently available treatment options can have substantial side effects and take weeks to be fully effective. Therefore, it is important to find safe alternatives, which act more rapidly and in a larger number of patients. While much research on MDD focuses on chronic stress as a main risk factor, we here make a point of exploring dietary factors as a somewhat overlooked, yet highly promising approach towards novel antidepressant pathways. Deficiencies in various groups of nutrients often occur in patients with mental disorders. These include vitamins, especially members of the B-complex (B6, B9, B12). Moreover, an imbalance of fatty acids, such as omega-3 and omega-6, or an insufficient supply with minerals, including magnesium and zinc, are related to MDD. While some of them are relevant for the synthesis of monoamines, others play a crucial role in inflammation, neuroprotection and the synthesis of growth factors. Evidence suggests that when deficiencies return to normal, changes in mood and behavior can be, at least in some cases, achieved. Furthermore, supplementation with dietary factors (so called "nutraceuticals") may improve MDD symptoms even in the absence of a deficiency. Non-vital dietary factors may affect MDD symptoms as well. For instance, the most commonly consumed psychostimulant caffeine may improve behavioral and molecular markers of MDD. The molecular structure of most dietary factors is well known. Hence, dietary factors may provide important molecular tools to study and potentially help treat MDD symptoms. Within this review, we will discuss the role of dietary factors in MDD risk and symptomology, and critically discuss how they might serve as auxiliary treatments or preventative options for MDD.

Peripheral Markers of Depression

Major Depressive Disorder (MDD) is a leading cause of disability worldwide, creating a high medical and socioeconomic burden. There is a growing interest in the biological underpinnings of depression, which are reflected by altered levels of biological markers. Among others, enhanced inflammation has been reported in MDD, as reflected by increased concentrations of inflammatory markers-C-reactive protein, interleukin-6, tumor necrosis factor-α and soluble interleukin-2 receptor. Oxidative and nitrosative stress also plays a role in the pathophysiology of MDD. Notably, increased levels of lipid peroxidation markers are characteristic of MDD. Dysregulation of the stress axis, along with increased cortisol levels, have also been reported in MDD. Alterations in growth factors, with a significant decrease in brain-derived neurotrophic factor and an increase in fibroblast growth factor-2 and insulin-like growth factor-1 concentrations have also been found in MDD. Finally, kynurenine metabolites, increased glutamate and decreased total cholesterol also hold promise as reliable biomarkers for MDD. Research in the field of MDD biomarkers is hindered by insufficient understanding of MDD etiopathogenesis, substantial heterogeneity of the disorder, common co-morbidities and low specificity of biomarkers. The construction of biomarker panels and their evaluation with use of new technologies may have the potential to overcome the above mentioned obstacles.

Zinc, but not paracetamol, prevents depressive-like behavior and sickness behavior, and inhibits interferon-gamma and astrogliosis in rats

Considering all mental and addictive disorders, depression is the most responsible for years of life lost due to premature mortality and disability. Antidepressant drugs have limited effectiveness. Depression can be triggered by immune/inflammatory factors. Zinc and paracetamol interfere with immune system and have demonstrated beneficial effects on depression treatment when administered concomitant with antidepressant drugs. The objective of this study was to test zinc and/or paracetamol as treatments of depressive-like behavior, sickness behavior, and anxiety in rats, as well as to understand the central and peripheral mechanisms involved. Sickness behavior and depressive-like behavior were induced in rats with repetitive lipopolysaccharide (LPS, 1 mg/kg for two consecutive days) administrations. Rats received zinc and/or paracetamol for three consecutive days. Sickness behavior (daily body weight and open field general activity); anxiety (light-dark test); depressive-like/antidepressant behavior (forced swim test); plasma corticosterone and interferon (IFN)-gamma levels; and glial fibrillary acidic protein (GFAP) and tyrosine hydroxylase (TH) brain expression were evaluated. LPS induced sickness behavior and depressive-like behavior, as well as elevated IFN-gamma levels and increased GFAP expression. Zinc prevented both behavioral and biochemical impairments. Paracetamol and zinc + paracetamol association induced only slight beneficial effects. Anxiety, corticosterone, and TH do not seem be related with depression and the other behavioral and neuroimmune changes. In conclusion, zinc treatment was beneficial for sickness behavior and depressive-like behavior without concomitant administration of antidepressants. IFN-gamma and GFAP were linked with the expression of sickness behavior and depressive-like behavior and were also involved with the antidepressant effects. Therefore, zinc, IFN-gamma, and GFAP pathways should be considered for depression treatment.

Nutrient patterns and depressive symptoms among Australian adults

PURPOSE

Much of the current literature on the associations between diet and depression focus on single nutrients rather than nutrient patterns (NPs). We investigated the association between NPs and depressive symptoms (DepS) in an Australian adult population.

METHODS

DepS were examined at two different time points, in 2010 (Stage 3, n = 1743, 49.0% males) and 2015 [North West 2015 (NW15), n = 1,024, 46.6% males] of the North West Adelaide Health Study (NWAHS). Dietary habits were evaluated using a food frequency questionnaire (FFQ) at Stage 3. DepS were assessed using the Center for Epidemiological Studies Depression (CES-D) scale at Stage 3 and NW15. Principal component analysis was used to identify NPs as well as the factor structure of the CES-D. Log- and negative binomial regression analyses were used to assess the association between NPs and DepS scores. Ordinal logistic regression analysis was undertaken between the NPs and identified factors of the CES-D score.

RESULTS

Three NPs (from the FFQ) and two-factors (from the CES-D score) were obtained. After adjusting for known confounding variables, a 'plant-sourced' NP (β-carotene, fibre, vitamin C, potassium and α-carotene) was inversely associated with DepS at Stage 3 [prevalence ratio (PR)_Q4VsQ1, 0.78; 95% CI 0.66-0.92; p = 0.003], whereas an 'animal-sourced' (ω-3 fatty acid, monounsaturated fat, vitamin E and cholesterol) or 'mixed-source' (phosphorous, protein, vitamin B2, iodine and zinc) NP was not associated with DepS. There was an inverse relationship between the 'plant-sourced' NP and the '(absence of) positive-affect' factor from the CES-D in both stages.

CONCLUSION

The 'plant-sourced' NP is consistently and inversely associated with DepS; however, longitudinal studies are recommended to confirm these results.

Simultaneous Fluorescence Imaging Reveals N-Methyl-d-aspartic Acid Receptor Dependent Zn2+/H+ Flux in the Brains of Mice with Depression

Depression is immensely attributed to the overactivation of N-methyl-d-aspartic acid (NMDA) receptor in the brains. As regulatory binding partners of NMDA receptor, both Zn²⁺ and H⁺ are intimately interrelated to NMDA receptor's activity. Therefore, exploring synergistic changes on the levels of Zn²⁺ and H⁺ in brains will promote the knowledge and treatment of depression. However, the lack of efficient, appropriate imaging tools limits simultaneously tracking Zn²⁺ and H⁺ in living mouse brains. Thus, a well-designed dual-color fluorescent probe (DNP) was fabricated for the simultaneous monitoring of Zn²⁺ and H⁺ in the brains of mice with depression. Encountering Zn²⁺, the probe evoked bright blue fluorescence at 460 nm. Meanwhile, the red fluorescence at 680 nm was decreased with H⁺ addition. With blue/red dual fluorescence signal of DNP, we observed the synchronous increased Zn²⁺ and H⁺ in PC12 cells under oxidative stress. Notably, in vivo imaging for the first time revealed the simultaneous reduction of Zn²⁺ and pH in brains of mice with depression-like behaviors. Further results implied that the NMDA receptor might be responsible for the coinstantaneous fluctuation of Zn²⁺ and H⁺ during depression. Altogether, this work is conducive to the knowledge of neural signal transduction mechanisms, advancing our understanding of the pathogenesis in depression.

Lowered zinc and copper levels in drug-naïve patients with major depression: Effects of antidepressants, ketoprofen and immune activation

Objectives: The aim of the present work is to examine the effects of treatment with sertraline with and without ketoprofen on serum levels of zinc and copper in association with immune-inflammatory biomarkers in drug-naïve major depressed patients.Methods: We measured serum zinc and copper, interleukin (IL)-1β, IL-4, IL-6, IL-18, interferon-γ, and transforming growth factor-β1 in 40 controls and 133 depressed patients. The clinical efficacy of the treatment was measured using the Beck Depression Inventory-II (BDI-II) at baseline and 8 weeks later.Results: We found significantly reduced serum zinc and copper in association with upregulation of all cytokines, indicating activation of the immune-inflammatory responses system (IRS) and the compensatory immune regulatory system (CIRS). Treatment with sertraline significantly increased zinc and decreased copper. During treatment, there was a significant inverse association between serum zinc and immune activation. The improvement in the BDI-II during treatment was significantly associated with increments in serum zinc coupled with attenuation of the IRS/CIRS.Conclusions: Lower zinc is a hallmark of depression, while increments in serum zinc and attenuation of the immune-inflammatory response during treatment appear to play a role in the clinical efficacy of sertraline.

Zinc Deficiency During Pregnancy Leads to Altered Microbiome and Elevated Inflammatory Markers in Mice

Zinc is an essential trace metal for bacteria of the intestinal flora. Approximately 20% of dietary zinc – intake is used by intestinal bacteria. The microbiome has recently been described as an important factor for healthy brain function via so-called gut-brain interactions. Similarly, zinc deficiency has been associated with neurological problems such as depression, mental lethargy and cognitive impairments in humans and animal models. However, the underlying pathomechanisms are currently not well understood and a link between zinc deficiency and altered microbiota composition has not been studied. Especially during pregnancy, women may be prone to low zinc status. Thus, here, we investigate whether zinc deficiency alters gut-brain interaction in pregnant mice by triggering changes in the microbiome. To that end, pregnant mice were fed different diets being zinc-adequate, deficient in zinc, or adequate in zinc but high in zinc uptake antagonists for 8 weeks. Our results show that acute zinc-deficient pregnant mice and pregnant mice on a diet high in zinc uptake antagonists have an altered composition of gastro-intestinal (GI) microbiota. These changes were accompanied by alterations in markers for GI permeability. Within the brain, we found signs of neuroinflammation. Interestingly, microbiota composition, gut pathology, and inflammatory cytokine levels were partially rescued upon supplementation of mice with zinc amino-acid conjugates (ZnAA). We conclude that zinc deficiency may contribute to abnormal gut-brain signaling by altering gut physiology, microbiota composition and triggering an increase of inflammatory markers.

Total and ionized calcium and magnesium are significantly lowered in drug-naïve depressed patients: effects of antidepressants and associations with immune activation

Major depressive disorder (MDD) is associated with alterations in calcium (Ca) and magnesium (Mg), as well as circulating pro- and anti-inflammatory cytokines. Anti-inflammatory drugs are commonly used as adjuvant treatments for MDD. However, no studies examined the effects of a combinatorial treatment with sertraline and ketoprofen, an anti-inflammatory drug, on Ca and Mg levels in MDD. The present study examined a) differences in both cations between drug-naïve MDD patients and controls, and b) the effects of sertraline and ketoprofen on Ca and Mg (both total and ionized). In the same patients, we also examined the associations between both cations and IL-1β, IL-4, IL-6, IL-18, IFN-γ, TGF-β1, zinc, and indoleamine 2,3-dioxygenase (IDO). Clinical improvement was assessed using the Beck Depression Inventory-II (BDI-II) at baseline and after follow up for 2 months. Serum Ca and Mg (total and ionized) were significantly lower in MDD patients as compared with controls, while treatment significantly increased calcium but decreased magnesium levels. There were significant and inverse correlations between the BDI-II scores from baseline to endpoint and Ca (both total and ionized), but not Mg, levels. The effects of calcium on the BDI-II score remained significant after considering the effects of zinc, IDO and an immune activation z unit-weighted composite score based on the sum of all cytokines. There was a significant and inverse association between this immune activation index and calcium levels from baseline to endpoint. In conclusion, lowered levels of both cations play a role in the pathophysiology of major depression. Antidepressant-induced increases in Ca are associated with clinical efficacy and attenuation of the immune response. The suppressant effect of antidepressants on Mg levels is probably a side effect of those drugs. New antidepressant treatments should be developed that increase the levels both Ca and Mg. Graphical abstract.

Long-lasting antidepressant-like activity of the GPR39 zinc receptor agonist TC-G 1008

BACKGROUND

The discovery of the zinc-sensing receptor, has provided new possibilities for explaining the neurobiology of zinc. Recent studies indicate that the GPR39 zinc receptor may play an important role in the pathogenesis of depression as well as in the antidepressant mechanism of action.

METHODS

In this study we evaluated the time-course of the antidepressant response of the GPR39 agonist (TC-G 1008), imipramine, ZnCl₂ and MK-801 in the forced swim test in mice 30 min, 3 h, 6 h and 24 h after acute drug administration as well as after 14-day treatment. Zinc level was measured in serum of mice. BDNF protein level was evaluated in hippocampus following both acute and chronic TC-G 1008 treatment.

RESULTS

A single administration of the GPR39 agonist caused an antidepressant-like effect lasting up to 24 h following the injection, which is longer than the effect of imipramine, ZnCl₂ and MK-801. Chronic treatment with these compounds caused a decrease in immobility time in the FST. Serum zinc concentrations showed an increased level following chronic ZnCl₂ administration, but not following administration of TC-G 1008, imipramine or MK-801. We also observed some tendencies for increased BDNF following acute TC-G 1008 treatment.

LIMITATIONS

TC-G 1008 is new drug designed to study GPR39 therefore additional pharmacodynamic and pharmacokinetic properties in preclinical studies are required.

CONCLUSION

This study shows for the first time the long-lasting antidepressant effect of the GPR39 agonist in comparison with imipramine, ZnCl2 and MK-801. Our findings suggest that GPR39 should be considered as a target in efforts to develop new antidepressant drugs.

Trace elements among a sample of prisoners with mental and personality disorders and aggression: correlation with impulsivity and ADHD indices

OBJECTIVES

Mental, personality and substance use disorders are over represented among prisoners and aggressive individuals. The psychopathological and biological markers linked to mental functioning remain still unclear. In particular, the role of trace elements in mental illness is still matter of debate. Here, we investigated whether trace elements are correlated to specific psychopathological phenotype groups.

METHODS

Axis I and II disorders, aggression, impulsivity, adult attention deficit/hyperactivity disorders (ADHD) indices and serum levels of zinc, copper and cadmium were evaluated in 160 male prisoners.

RESULTS

Using latent class analysis we could subdivide prisoners into three distinct psychopathological classes: Class 1 characterized by low prevalence of aggression, personality disorders and substance abuse/dependence (alcohol, cannabis, cocaine); Class 2 represented by low prevalence of aggression and high prevalence of personality disorders and substance abuse/dependence; Class 3 defined by high prevalence of aggression, personality disorders and substance abuse/dependence. Serum levels of zinc were higher in Class 2 and 3 compared to Class 1. Moreover, Class 3 was associated with higher scores of impulsivity and ADHD indices.

CONCLUSION

Our results suggest that impulsivity but also adult ADHD indices are related to aggressive behaviour, and higher zinc levels are linked to personality disorders and addictions, but not to aggression.

Relationship of Dietary and Serum Zinc with Depression Score in Iranian Adolescent Girls

Zinc deficiency, which is common among Iranian populations, is believed to play a crucial role in the onset and progression of mood disorders such as depression in different stages of life. We have therefore investigated the relationship between serum/dietary zinc status and depression scores among adolescent girls living in northeastern Iran. Serum zinc was measured by flame atomic absorption (Varian AA240FS) and the mean zinc intake was assessed using 3-day food record. A validated Persian version of the Beck Depression Inventory (BDI) was used to determine the severity of depressive symptoms for all subjects. Data were analyzed using SPSS 18 software. There was a statistically significant correlation between dietary zinc intake and serum zinc concentration (r = 0.117, p = 0.018). Dietary intake of zinc (7.04 ± 4.28 mg/day) was significantly lower among subjects with mild to severe depression symptoms than those with no or minimal depression symptoms (8.06 ± 3.03 mg/day). Dietary zinc intake was inversely correlated with depression score (r = 0.133, p = 0.008). However, there was no significant difference in serum zinc concentrations among individuals with no or minimal and mild to severe depression symptoms (p = 0.5). Dietary zinc intake, but not serum zinc concentration, was inversely associated with depression symptoms. Therefore, controlled clinical trials are needed to determine the efficacy of zinc supplementation in the treatment of depression disorders.

Serum zinc levels in acute psychiatric patients: A case series

Zinc dysregulation is linked to neuropsychiatric disorders and a beneficial response to zinc supplementation has been demonstrated for depression. In this case series, we examined serum zinc levels with respect to clinical factors among 20 acutely ill psychiatric cases admitted to a large urban public hospital. The results showed frank clinical zinc insufficiency in a quarter of the subjects. Group-wise analyses showed a significant association between reduced serum zinc and diagnosis of depression, and reduced serum zinc in those with aggressive, assaultive, or violent behaviors. By contrast, relatively elevated zinc levels were observed in a subset of psychotic cases on antipsychotics and mood stabilizers who had no mood symptoms. In summary, clinical zinc insufficiency was common in these acutely admitted psychiatric cases. Zinc supplementation may ameliorate symptoms in certain cases and should be considered in treatment planning. A separate patient group had elevated zinc levels, which could conceivably be pathogenic. Larger studies are needed to confirm and extend this pilot data.

Supplements, nutrition, and alternative therapies for the treatment of traumatic brain injury

Studies using traditional treatment strategies for mild traumatic brain injury (TBI) have produced limited clinical success. Interest in treatment for mild TBI is at an all time high due to its association with the development of chronic traumatic encephalopathy and other neurodegenerative diseases, yet therapeutic options remain limited. Traditional pharmaceutical interventions have failed to transition to the clinic for the treatment of mild TBI. As such, many pre-clinical studies are now implementing non-pharmaceutical therapies for TBI. These studies have demonstrated promise, particularly those that modulate secondary injury cascades activated after injury. Because no TBI therapy has been discovered for mild injury, researchers now look to pharmaceutical supplementation in an attempt to foster success in human clinical trials. Non-traditional therapies, such as acupuncture and even music therapy are being considered to combat the neuropsychiatric symptoms of TBI. In this review, we highlight alternative approaches that have been studied in clinical and pre-clinical studies of TBI, and other related forms of neural injury. The purpose of this review is to stimulate further investigation into novel and innovative approaches that can be used to treat the mechanisms and symptoms of mild TBI.

Association of Serum Trace Elements with Schizophrenia and Effects of Antipsychotic Treatment

Variation of serum trace elements was previously reported in schizophrenia (SZ) patients; however, whether such variation is resulted from the antipsychotic treatment remains obscure. A case control study consist of 165 SZ inpatients and 614 healthy controls measured serum magnesium (Mg), Copper (Cu), calcium (Ca), phosphorus (Phos), iron (Fe), and zinc (Zn) to investigate the relationship of trace elements and SZ. The SZ patients were further followed up (average 3.8 weeks) to evaluate the effects of antipsychotic treatment on the trace element concentrations using repeated measures ANOVA analysis. The results showed that higher concentrations of Mg and Phos and lower concentrations of Ca, Fe, and Zn were significant in SZ patients than that of controls (P < 0.01). The age was positively correlated with Fe and Cu, and negatively correlated with Ca, Phos, and Zn in controls (P < 0.05). Fe in male SZ patients was significantly higher than in female (P < 0.001), as well as in paranoid SZ and acute SZ (P < 0.05). Phos significantly increased after risperidone, clozapine, and aripiprazole treatment (P < 0.05), while Cu was decreased after clozapine and aripiprazole treatment. Zn significantly decreased particularly in mixed type SZ, acute SZ, and schizotypal SZ after antipsychotic treatment. These results suggested that higher concentration of Phos and lower concentration of Fe and Zn have important implications for the risk of SZ and the antipsychotic treatment is likely to result in the decreased Fe and increased Phos in the clinical subtypes of SZ.

Zinc Signal in Brain Diseases

The divalent cation zinc is an integral requirement for optimal cellular processes, whereby it contributes to the function of over 300 enzymes, regulates intracellular signal transduction, and contributes to efficient synaptic transmission in the central nervous system. Given the critical role of zinc in a breadth of cellular processes, its cellular distribution and local tissue level concentrations remain tightly regulated via a series of proteins, primarily including zinc transporter and zinc import proteins. A loss of function of these regulatory pathways, or dietary alterations that result in a change in zinc homeostasis in the brain, can all lead to a myriad of pathological conditions with both acute and chronic effects on function. This review aims to highlight the role of zinc signaling in the central nervous system, where it may precipitate or potentiate diverse issues such as age-related cognitive decline, depression, Alzheimer's disease or negative outcomes following brain injury.

Peripheral zinc and neopterin concentrations are associated with mood severity in bipolar disorder in a gender-specific manner

Bipolar disorder (BD) is a recurrent, episodic mood disorder for which there are no current diagnostic, prognostic or theranostic biomarkers. Two peripheral markers of the acute phase immune response, zinc and neopterin, are consistently associated with severity of depression in literature. Given gender differences in clinical presentation of BD and in inflammatory processes, we aimed to explore the interaction between gender and immune biomarkers to predict mood severity in BD. Participants with DSM IV BD I and II were recruited through the Pennsylvania Psychiatric Institute during an acute mood episode. Healthy controls (HC) were recruited through advertisements. Participants fasted for at least 6h when blood was drawn for biomarkers. We found that zinc concentrations were significantly lower in the BD group at baseline (p<.05), and there was also a significant interaction between gender and zinc (p<.05), associated with depression severity. Also, we found a significant interaction between gender and neopterin, associated with mania severity (p<.05). We found that mania severity was associated with neopterin in men, while depression severity was positively associated with zinc in women. Our report bears replication in larger samples and highlights the potential for differences in the underlying pathophysiology between men and women with BD.

Association of Mood Disorders with Serum Zinc Concentrations in Adolescent Female Students

Among various factors influencing mood disorders, the impact of micronutrient deficiencies has attracted a great attention. Zinc deficiency is considered to play a crucial role in the onset and progression of mood disorders in different stages of life. The main objective of this study was to assess the correlation between serum zinc levels and mood disorders in high school female students. This cross-sectional study was conducted on a random sample of 100 representative high school female students. The participants completed 24-h food recall questionnaires to assess the daily zinc intakes. Serum zinc status was assessed using flame atomic absorption spectrometry, and zinc deficiency was defined accordingly. Mood disorders were estimated by calculating the sum of two test scores including Beck's depression inventory (BDI) and hospital anxiety depression scale (HADS) tests. General linear model (GLM) and Pearson's regression test were applied to show the correlation of serum zinc levels and mood disorder scores and the correlation between zinc serum levels and BDI scores, respectively. Dietary zinc intake was higher in subjects with normal zinc concentrations than that of zinc-deficient group (p = 0.001). Serum zinc levels were inversely correlated with BDI and HADS scores (p < 0.05). Each 10 μg/dL increment in serum zinc levels led to 0.3 and 0.01 decrease in depression and anxiety scores, respectively (p < 0.05). Serum zinc levels were inversely correlated with mood disorders including depression and anxiety in adolescent female students. Increasing serum levels of zinc in female students could improve their mood disorders.

The Emerging Role for Zinc in Depression and Psychosis

Zinc participation is essential for all physiological systems, including neural functioning, where it participates in a myriad of cellular processes. Converging clinical, molecular, and genetic discoveries illuminate key roles for zinc homeostasis in association with clinical depression and psychosis which are not yet well appreciated at the clinical interface. Intracellular deficiency may arise from low circulating zinc levels due to dietary insufficiency, or impaired absorption from aging or medical conditions, including alcoholism. A host of medications commonly administered to psychiatric patients, including anticonvulsants, oral medications for diabetes, hormones, antacids, anti-inflammatories and others also impact zinc absorption. Furthermore, inefficient genetic variants in zinc transporter molecules that transport the ion across cellular membranes impede its action even when circulating zinc concentrations is in the normal range. Well powered clinical studies have shown beneficial effects of supplemental zinc in depression and it important to pursue research using zinc as a potential therapeutic option for psychosis as well. Meta-analyses support the adjunctive use of zinc in major depression and a single study now supports zinc for psychotic symptoms. This manuscript reviews the biochemistry and bench top evidence on putative molecular mechanisms of zinc as a psychiatric treatment.

Dietary zinc and iron intake and risk of depression: A meta-analysis

The associations between dietary zinc and iron intake and risk of depression remain controversial. Thus, we carried out a meta-analysis to evaluate these associations. A systematic search was performed in PubMed, Embase, Web of Science, Chinese National Knowledge Infrastructure (CNKI) and Wanfang databases for relevant studies up to January 2017. Pooled relative risks (RRs) with 95% confidence intervals (CIs) were calculated using a random effects model. A total of 9 studies for dietary zinc intake and 3 studies for dietary iron intake were finally included in present meta-analysis. The pooled RRs with 95% CIs of depression for the highest versus lowest dietary zinc and iron intake were 0.67 (95% CI: 0.58-0.76) and 0.57 (95% CI: 0.34-0.95), respectively. In subgroup analysis by study design, the inverse association between dietary zinc intake and risk of depression remained significant in the cohort studies and cross-sectional studies. The pooled RRs (95% CIs) for depression did not substantially change in the influence analysis and subgroup analysis by adjustment for body mass index (BMI). The present meta-analysis indicates inverse associations between dietary zinc and iron intake and risk of depression.

Alterations of Hair and Nail Content of Selected Trace Elements in Nonoccupationally Exposed Patients with Chronic Depression from Different Geographical Regions

The aim of this study was to determine if altered levels of selected trace elements manifest themselves during chronic depression. To identify elements strongly associated with chronic depression, relationships between the elemental contents of hair and nails and the interelement correlations were checked. Inductively coupled plasma mass spectrometry and ion chromatography were used to evaluate the contents of Zn, Cu, Co, Pb, Mn, and Fe in hair and nail samples from a total of 415 subjects (295 patients and 120 healthy volunteers). The study included logistic regression models to predict the probability of chronic depression. To investigate possible intercorrelations among the studied elements, the scaled principal component analysis was used. The research has revealed differences in TE levels in the group of depressed men and women in comparison to the healthy subjects. Statistically significant differences in both hair and nails contents of several elements were observed. Our study also provides strong evidence that the intermediary metabolism of certain elements is age- and gender-dependent. Zn, Mn, Pb, and Fe contents in hair/nails seem to be strongly associated with chronic depression. We found no statistically significant residence-related differences in the contents of studied elements in nonoccupationally exposed patients and healthy subjects.

Analysis of Relations Between the Level of Mg, Zn, Ca, Cu, and Fe and Depressiveness in Postmenopausal Women

Numerous observations suggest a possible connection between the levels of Mg, Zn, Fe, and Zn and the incidence of depressive symptoms. Depression is two to three times more common in women than in men. The menopausal period is extremely conducive to depressive disorders. The aim of this study was to assess the severity of depressive symptoms in postmenopausal women depending on the levels of Mg, Zn, Ca, Cu, and Fe. The study included 198 healthy postmenopausal women at the average age of 56.26 ± 5.55 years. In the first part of the study, standardized research tools were used, namely the Primary Care Evaluation of Mental Disorders (PRIME-MD) and the Beck Depression Inventory (BDI). The second part involved biochemical analysis of Mg, Zn, Ca, Cu, and Fe levels in blood serum. The lowest Cu levels were observed in women without depressive symptoms (1.07 ± 0.22 mg/l) and the highest in those with severe depressive symptoms (1.19 ± 0.17 mg/l), (p ≤ 0.05). The lowest Mg levels were observed in women with depressive symptoms (14.28 ± 2.13 mg/l), and the highest in women without depressive symptoms (16.30 ± 3.51 mg/l), (p ≤ 0.05). The average serum Mg levels (15.75 ± 3.23 mg/l) decreased compared to the reference values (18.77-24 mg/l). What is striking is a potential relation between the levels of Mg and Cu and depressiveness. Our results indicate to a higher vulnerability to depression in a group of women with lower levels of Mg and higher levels of Cu.

The serum zinc concentration as a potential biological marker in patients with major depressive disorder

Despite many clinical trials assessing the role of zinc in major depressive disorder (MDD), the conclusions still remain ambiguous. The aim of the present clinical study was to determine and comparison the zinc concentration in the blood of MDD patients (active stage or remission) and healthy volunteers (controls), as well as to discuss its potential clinical usefulness as a biomarker of the disease. In this study 69 patients with current depressive episode, 45 patients in remission and 50 controls were enrolled. The zinc concentration was measured by electrothermal atomic absorption spectrometry (ET AAS). The obtained results revealed, that the zinc concentration in depressed phase were statistically lower than in the healthy volunteers [0.89 vs. 1.06 mg/L, respectively], while the zinc level in patients achieve remission was not significantly different from the controls [1.07 vs. 1.06 mg/L, respectively]. Additionally, among the patients achieve remission a significant differences in zinc concentration between group with and without presence of drug-resistance in the previous episode of depression were observed. Also, patients in remission demonstrated correlation between zinc level and the average number of depressive episodes in the last year. Serum zinc concentration was not dependent on atypical features of depression, presence of psychotic symptoms or melancholic syndrome, age, age of onset or duration of disease, number of episodes in the life time, duration of the episode/remission and severity of depression measured by the Hamilton Rating Scale for Depression (HDRS), and the Montgomery-Asberg Depression Rating Scale (MADRS). Concluding, our findings confirm the correlation between zinc deficit present in the depressive episode, and are consistent with the majority of previous studies. These results may also indicate that serum zinc concentration might be considered as a potential biological marker of MDD.

Is there an association between diet and depression in children and adolescents? A systematic review

This review critically evaluates previous studies investigating the association between dietary intake of children and young people and depression and related mental health problems. A systematic literature search was conducted using electronic databases such as PsycINFO, MEDLINE, PubMed and Cochrane. A total of twenty studies were identified that met inclusion criteria and were subsequently rated for quality. The studies used a range of methods to measure dietary intake and mental health. Important potential confounding variables (e.g. socio-economic status) were often not included or controlled. There were also inconsistencies in the use of key constructs, which made comparisons between studies difficult. Despite some contradictory results, overall there was support for an association between healthy dietary patterns or consumption of a high-quality diet and lower levels of depression or better mental health. Similarly, there was a relationship between unhealthy diet and consumption of low-quality diet and depression or poor mental health. However, where significant relationships were reported, effect sizes were small. Future research on the relationship between diet and mental health in young people should use more clearly defined constructs to define diet and include or control for important confounders.

The level of the zinc homeostasis regulating proteins in the brain of rats subjected to olfactory bulbectomy model of depression

BACKGROUND

Zinc transporters (ZnTs) and metallothioneins (MT) are important in maintaining Zn homeostasis in the brain. The present study was designed to find out whether alterations in ZnTs and MTs are associated with the pathophysiology of depression and the mechanism of antidepressant action.

METHODS

Messenger RNA and proteins of ZnT1, ZnT3, ZnT4, ZnT5, ZnT6 and MT1/2 were measured in the prefrontal cortex (PFC) and hippocampus (Hp) of rats subjected to olfactory bulbectomy (OB) (a model of depression) and chronic amitriptyline (AMI) treatment by Real Time PCR and Western Blot/Immunohistochemistry (IHP).

RESULTS

Results in the OB rats showed: increases in the protein levels of ZnT1 in the PFC and Hp and MT1/2 in the PFC; a decrease in ZnT3 protein level in the PFC; no changes in ZnT4, ZnT5 and ZnT6 in the PFC and Hp. IHP labeling revealed increases in the optical densities of ZnT1-IR in the PFC and Hp and decreases in ZnT3 and ZnT4-IR in the PFC of OB rats. Although OB had no effects on gene expression of ZnTs, mRNAs for MT1/2 were increased. Chronic AMI treatment did not influence protein levels of ZnTs and MT1/2 in Sham and OB rats; however decreased mRNA levels of ZnT4 and ZnT5 in PFC and ZnT1, ZnT3, ZnT4 and ZnT6 in Hp of Sham rats and normalized OB induced increase in MT1/2 gene expression.

CONCLUSIONS

Changes in ZnTs and MT1/2 suggest altered cortical distribution of Zn in the OB model which further supports the hypothesis that Zn dyshomeostasis may be involved in the pathophysiology of depression.

The Effects of Four-Week Multivitamin Supplementation on Mood in Healthy Older Women: A Randomized Controlled Trial

Objective. Nutritional deficiencies have been associated with cognitive decline and mood disturbances. Vitamin intake can influence mood and randomized controlled trials have demonstrated that multivitamin supplements are capable of reducing mild symptoms of mood dysfunction. However, few studies have focussed on healthy older women. Methods. This study investigated the effects of four weeks' multivitamin supplementation on mood in 76 healthy women aged 50-75 years. Mood was assessed before and after intervention in the laboratory using measures of current mood and retrospective experiences of mood over the past week or longer. Mobile phones were used to assess changes in real-time mood ratings, twice weekly in the home. Results. There were no multivitamin-related benefits identified for measures of current mood or reflections of recent mood when measured in the laboratory. In-home assessments, where mood was rated several hours after dose, revealed multivitamin supplementation improved ratings of stress, with a trend to reduce mental fatigue. Conclusions. Over four weeks, subtle changes to stress produced by multivitamin supplementation in healthy older women may not be detected when only pre- and posttreatment mood is captured. In-home mobile phone-based assessments may be more sensitive to the effects of nutritional interventions compared to traditional in-laboratory assessments.

Zinc transporters protein level in postmortem brain of depressed subjects and suicide victims

BACKGROUND

Major depressive disorder (MDD) is a serious psychiatric illness, associated with an increasing rate of suicide. The pathogenesis of depression may be associated with the disruption of zinc (Zn) homeostasis. In the brain, several proteins that regulate Zn homeostasis are present, including Zn transporters (ZnTs) which remove Zn from the cytosol. The present study was designed to investigate whether depression and suicide are associated with alterations in the expression of the ZnTs protein.

METHODS

Protein levels of ZnT1, ZnT3, ZnT4, ZnT5 and ZnT6 were measured in postmortem brain tissue from two different cohorts. Cohort A contained 10 subjects diagnosed with MDD (7 were suicide victims) and 10 psychiatrically-normal control subjects and cohort B contained 11 non-diagnosed suicide victims and 8 sudden-death control subjects. Moreover, in cohort A we measured protein level of NMDA (GluN2A subunit), AMPA (GluA1 subunit) and 5-HT1A receptors and PSD-95. Proteins were measured in the prefrontal cortex (PFC) using Western blotting. In addition, Zn concentration was measured using a voltammetric method.

RESULTS

There was a significant increase in protein levels of ZnT1, ZnT4, ZnT5 in the PFC in MDD, relative to control subjects, while ZnT3 protein level was decreased in MDD. There was no significant difference in the Zn concentration in the PFC between control and MDD subjects. Similarly, in the PFC of suicide victims (non-diagnosed), an increase in protein levels of ZnT1, ZnT4, ZnT5 and ZnT6 was observed. Conversely, protein levels of ZnT3 were decreased in both suicide victims and subjects with MDD, in comparison with control subjects. There was also a significant decrease in the protein level of GluA1, GluN2A, PSD-95 and 5-HT1A in MDD.

CONCLUSIONS

Our studies suggest that alterations in Zn transport proteins are associated with the pathophysiology of MDD and suicide.

Níveis de zinco sérico em pacientes internados com depressão

RESUMO Objetivo Comparar pacientes internados com depressão e com transtorno de humor bipolar em episódio depressivo quanto aos níveis séricos de zinco. Métodos Foram incluídos 46 pacientes com idade igual ou superior a 19 anos, de ambos os sexos, internados em Unidade de Internação Psiquiátrica de um hospital universitário do sul do Brasil. Os participantes foram divididos em dois grupos: Grupo Depressão (Grupo D) e Grupo com Transtorno de Humor Bipolar em episódio depressivo (Grupo THB). A análise do zinco sérico foi realizada por meio de espectrofotometria de absorção atômica. Como valores de referência para normalidade, foram adotados níveis de zinco sérico acima de 59 µg/dL para mulheres e acima de 61 µg/dL para homens. Resultados Os níveis de zinco sérico estavam dentro do padrão de normalidade em 95,7% dos pacientes. A mediana de zinco no Grupo D foi de 88,5 µg/dL e de 81,5 µg/dL no Grupo THB, porém essa diferença não foi estatisticamente significativa. O Grupo THB apresentou valores maiores de índice de massa corporal (IMC), LDL colesterol e mais internações psiquiátricas prévias. Conclusão Os resultados encontrados no presente estudo mostram que os níveis de zinco sérico em pacientes em uso de antidepressivos e outras medicações psiquiátricas, internados por THB em episódio depressivo, quando comparados a pacientes com depressão, não diferiram e estavam dentro da faixa de normalidade. O uso dessas medicações pode ter influência nas concentrações séricas do mineral.

Serum zinc concentrations and depression in persons with Human Immunodeficiency Virus infection: The positive living with HIV (POLH) study

Low levels of serum zinc concentrations and depression are common in persons infected with Human Immunodeficiency Virus (HIV). Low levels of serum zinc concentrations may increase risk of depression in general population. However, research on the role of zinc in depression among HIV- infected person is limited. We assessed the association between serum zinc concentrations and depression in HIV-infected persons. A cross-sectional survey was conducted among 311 HIV-positive people (177 men and 134 women) aged 18-60 years residing in Kathmandu, Nepal. The atomic absorption method was used to measure serum zinc concentrations and the Beck Depression Inventory (BDI)-Ia method was used to measure depression, with cut off score 20 or higher consistent with clinically significant depression. Relationships were assessed using multiple linear and logistic regression analyses. Serum zinc concentrations were significantly inversely associated with depression in all participants and in men but not in women. Participants with the highest tertile of serum zinc concentrations had a significantly decreased risk of depression in men but not in women. Serum zinc concentrations were inversely associated with depressive symptoms scores in HIV-infected men. Further prospective studies are needed to confirm the role of zinc in depression among persons infected with HIV.

Behavioral Abnormality Induced by Enhanced Hypothalamo-Pituitary-Adrenocortical Axis Activity under Dietary Zinc Deficiency and Its Usefulness as a Model

Dietary zinc deficiency increases glucocorticoid secretion from the adrenal cortex via enhanced hypothalamo-pituitary-adrenocortical (HPA) axis activity and induces neuropsychological symptoms, i.e., behavioral abnormality. Behavioral abnormality is due to the increase in glucocorticoid secretion rather than disturbance of brain zinc homeostasis, which occurs after the increase in glucocorticoid secretion. A major target of glucocorticoids is the hippocampus and their actions are often associated with disturbance of glutamatergic neurotransmission, which may be linked to behavioral abnormality, such as depressive symptoms and aggressive behavior under zinc deficiency. Glucocorticoid-mediated disturbance of glutamatergic neurotransmission in the hippocampus is also involved in the pathophysiology of, not only psychiatric disorders, such as depression, but also neurodegenerative disorders, e.g., Alzheimer’s disease. The evidence suggests that zinc-deficient animals are models for behavioral and psychological symptoms of dementia (BPSD), as well as depression. To understand validity to apply zinc-deficient animals as a behavioral abnormality model, this paper deals with the effect of antidepressive drugs and herbal medicines on hippocampal dysfunctions and behavioral abnormality, which are induced by enhanced HPA axis activity under dietary zinc deficiency.

Phenotypically distinct subtypes of psychosis accompany novel or rare variants in four different signaling genes

BACKGROUND

Rare gene variants are important sources of schizophrenia vulnerability that likely interact with polygenic susceptibility loci. This study examined if novel or rare missense coding variants in any of four different signaling genes in sporadic schizophrenia cases were associated with clinical phenotypes in an exceptionally well-characterized sample.

METHOD

Structured interviews, cognition, symptoms and life course features were assessed in 48 ethnically-diverse cases with psychosis who underwent targeted exome sequencing of PTPRG (Protein Tyrosine Phosphatase, Receptor Type G), SLC39A13 (Solute Carrier Family 39 (Zinc Transporter) Member 13), TGM5 (transglutaminase 5) and ARMS/KIDINS220 (Ankyrin repeat-rich membrane spanning protein or Kinase D-Interacting Substrate of 220kDa). Cases harboring rare missense coding polymorphisms or novel mutations in one or more of these genes were compared to other cases not carrying any rare missense coding polymorphisms or novel mutations in these genes and healthy controls.

FINDINGS

Fifteen of 48 cases (31.25%) carried rare or novel missense coding variants in one or more of these genes. The subgroups significantly differed in important features, including specific working memory deficits for PTPRG (n=5); severe negative symptoms, global cognitive deficits and poor educational attainment, suggesting a developmental disorder, for SLC39A13 (n=4); slow processing speed, childhood attention deficit disorder and milder symptoms for TGM5 (n=4); and global cognitive deficits with good educational attainment suggesting neurodegeneration for ARMS/KIDINS220 (n=5). Case vignettes are included in the appendix.

INTERPRETATION

Genes prone to missense coding polymorphisms and/or mutations in sporadic cases may highlight influential genes for psychosis and illuminate heterogeneous pathways to schizophrenia. Ethnicity appears less important at the level of genetic variability. The sequence variations that potentially alter the function of specific genes or their signaling partners may contribute to particular subtypes of psychosis. This approach may be applicable to other complex disorders.

Lower Serum Zinc and Higher CRP Strongly Predict Prenatal Depression and Physio-somatic Symptoms, Which All Together Predict Postnatal Depressive Symptoms

Pregnancy and delivery are associated with activation of immune-inflammatory pathways which may prime parturients to develop postnatal depression. There are, however, few data on the associations between immune-inflammatory pathways and prenatal depression and physio-somatic symptoms. This study examined the associations between serum zinc, C-reactive protein (CRP), and haptoglobin at the end of term and prenatal physio-somatic symptoms (fatigue, back pain, muscle pain, dyspepsia, obstipation) and prenatal and postnatal depressive and anxiety symptoms as measured using the Edinburgh Postnatal Depression Scale (EPDS), Beck Depression Inventory (BDI), Hamilton Depression Rating Scale (HAMD), and Spielberger's State Anxiety Inventory (STAI). Zinc and haptoglobin were significantly lower and CRP increased at the end of term as compared with non-pregnant women. Prenatal depression was predicted by lower zinc and lifetime history of depression, anxiety, and premenstrual tension syndrome (PMS). The latter histories were also significantly and inversely related to lower zinc. The severity of prenatal EDPS, HAMD, BDI, STAI, and physio-somatic symptoms was predicted by fatigue in the first and second trimesters, a positive life history of depression, anxiety, and PMS, and lower zinc and higher CRP. Postnatal depressive symptoms are predicted by prenatal depression, physio-somatic symptoms, zinc and CRP. Prenatal depressive and physio-somatic symptoms have an immune-inflammatory pathophysiology, while postnatal depressive symptoms are highly predicted by prenatal immune activation, prenatal depression, and a lifetime history of depression and PMS. Previous episodes of depression, anxiety disorders, and PMS may prime pregnant females to develop prenatal and postnatal depressive symptoms via activated immune pathways.

Decreased serum zinc concentration during depressive episode in patients with bipolar disorder

OBJECTIVES

Zinc may be involved in the pathophysiology and treatment of depressive disorder. However, data on this issue in bipolar disorder (BD) are limited. The aim of the study was to assess zinc concentrations in the blood serum of patients at various phases and stages of bipolar disorder.

METHODS

The study included 129 patients with a diagnosis of bipolar disorder type I (n=69) or type II (n=60). Fifty-eight were in a depressive episode, 23 in a manic episode and 48 in remission. Fifty healthy volunteers made a control group. Zinc concentration was measured using flame atomic absorption spectrometry.

RESULTS

Serum zinc level in patients diagnosed with BD type I in the depressive phase was significantly reduced as compared with mania, remission and healthy subjects. In the BD type II, serum zinc level in hypomania, depression or remission phase was not significantly different from the control group. In the whole group, lower level of zinc in depression compared to remission and control subjects was found during late stage of the illness but not in the early stage. Zinc concentration was not dependent on the severity of manic or depressive symptoms and subtype of depression but correlated positively with the number of manic/hypomanic relapses in the past year.

LIMITATIONS

Lack of prospective model, heterogeneity of pharmacological treatment, small number of subgroups presenting specified clinical features.

CONCLUSIONS

Decreased serum zinc concentration occurs in depression in BD type I and probably in depression in the late stage of BD.

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.

Activation of mTOR dependent signaling pathway is a necessary mechanism of antidepressant-like activity of zinc

The rapid antidepressant response to the N-methyl-D-aspartate (NMDA) receptor antagonists is mediated by activation of the mammalian target of the rapamycin (mTOR) signaling pathway, an increase in the synthesis of synaptic proteins and formation of new synapses in the prefrontal cortex (PFC) of rats. Zinc (Zn), which is a potent NMDA receptor antagonist, exerts antidepressant-like effects in screening tests and models of depression. We focused these studies in investigating whether activation of the mTOR signaling pathway is also a necessary mechanism of the antidepressant-like activity of Zn. We observed that a single injection of Zn (5 mg/kg) induced an increase in the phosphorylation of mTOR and p70S6K 30 min and 3 h after Zn treatment at time points when Zn produced also an antidepressant-like effect in the forced swim test (FST). Furthermore, Zn administered 3 h before the decapitation increased the level of brain derived neurotrophic factor (BDNF), GluA1 and synapsin I. An elevated level of GluA1 and synapsin I was still observed 24 h after the Zn treatment, although Zn did not produce any effects in the FST at that time point. We also observed that pretreatment with rapamycin (mTORC1 inhibitor), LY294002 (PI3K inhibitor), H-89 (PKA inhibitor) and GF109203X (PKC inhibitor) blocked the antidepressant-like effect of Zn in FST in rats and blocks Zn-induced activation of mTOR signaling proteins (analyzed 30 min after Zn administration). These studies indicated that the antidepressant-like activity of Zn depends on the activation of mTOR signaling and other signaling pathways related to neuroplasticity, which can indirectly modulate mTOR function.

Up-regulation of the GPR39 Zn2+-sensing receptor and CREB/BDNF/TrkB pathway after chronic but not acute antidepressant treatment in the frontal cortex of zinc-deficient mice

BACKGROUND

The GPR39-Zn(2+)-sensing receptor seems to be involved in the pathophysiology of depression. GPR39 knockout animals show depressive- and anxiety-like behavior. Chronic treatment with selective antidepressants (ADs) up-regulates GPR39.

OBJECTIVE AND METHODS

In the present study we investigated whether acute or chronic treatment with imipramine, escitalopram, reboxetine and bupropion would cause changes in CREB, BDNF, TrkB and GPR39-Zn(2+) receptor proteins (measured by Western Blot) in the frontal cortex of mice fed with a low-zinc diet.

RESULTS

The administration of acute antidepressants induced diverse effects in the proteins that were examined (namely, GPR39 down-regulation and a reduction in CREB protein after administration of all ADs; a decrease in BDNF after administration of imipramine and escitalopram; an increase in BDNF after administration of reboxetine; no change in BDNF following administration of bupropion; and a decrease in TrkB following the administration of all ADs except bupropion). On the other hand, chronic treatment (which is required for depression relief) with all antidepressants increased the levels of all these proteins.

CONCLUSIONS

The present study for the first time demonstrates the up-regulation of GPR39 (and CREB, BDNF, and TrkB) protein when induced by chronic treatment with antidepressants (with different pharmacological profiles) in a zinc-deficiency model in mice. These data further indicate that the GPR39 receptor may be an important target in the antidepressant response.