A Meta-Analysis of Oxidative Stress Markers in Depression

N-acetylcysteine for major mental disorders: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

This systematic review and meta-analysis of randomized controlled trials (RCTs) examined the efficacy and safety of adjunctive N-acetylcysteine (NAC), an antioxidant drug, in treating major depressive disorder (MDD), bipolar disorder, and schizophrenia.

METHODS

The PubMed, Cochrane Library, PsycINFO, CNKI, CBM, and WanFang databases were independently searched and screened by two researchers. Standardized mean differences (SMDs), risk ratios, and their 95% confidence intervals (CIs) were computed.

RESULTS

Six RCTs (n = 701) of NAC for schizophrenia (three RCTs, n = 307), bipolar disorder (two RCTs, n = 125), and MDD (one RCT, n = 269) were identified and analyzed as separate groups. Adjunctive NAC significantly improved total psychopathology (SMD = -0.74, 95% CI: -1.43, -0.06; I² = 84%, P = 0.03) in schizophrenia, but it had no significant effect on depressive and manic symptoms as assessed by the Young Mania Rating Scale in bipolar disorder and only a small effect on major depressive symptoms. Adverse drug reactions to NAC and discontinuation rates between the NAC and control groups were similar across the three disorders.

CONCLUSIONS

Adjunctive NAC appears to be a safe treatment that has efficacy for schizophrenia, but not for bipolar disorder or MDD. Further higher quality RCTs are warranted to determine the role of adjunctive NAC in the treatment of major psychiatric disorders.

Tryptophan-kynurenine and lipid related metabolites as blood biomarkers for first-episode drug-naïve patients with major depressive disorder: An exploratory pilot case-control study

BACKGROUND

Early intervention in depression has been critical to prevent its negative impact including suicide. Recent blood biomarker studies for major depressive disorder (MDD) have suggested that tryptophan-kynurenine and lipid related metabolites are involved in the pathophysiology of MDD. However, there have been limited studies investigating these blood biomarkers in first-episode drug-naïve MDD, which are particularly important for early intervention in depression.

METHODS

As an exploratory pilot case-control study, we examined the above blood biomarkers, and analyzed how these biomarkers are associated with clinical variables in first-episode drug-naïve MDD patients, based on metabolome/lipidome analysis.

RESULTS

Plasma tryptophan and kynurenine levels were significantly lower in MDD group (N = 15) compared to healthy controls (HC) group (N = 19), and plasma tryptophan was the significant biomarker to identify MDD group (area under the curve = 0.740). Lower serum high density lipoprotein-cholesterol (HDL-C) was the predictive biomarker for severity of depression in MDD group (R² = 0.444). Interestingly, depressive symptoms were variously correlated with plasma tryptophan-kynurenine and lipid related metabolites. Moreover, plasma tryptophan-kynurenine metabolites and cholesteryl esters (CEs) were significantly correlated in MDD group, but not in HC group.

LIMITATIONS

This study had small sample size, and we did not use the multiple test correction.

CONCLUSIONS

This is the first study to suggest that not only tryptophan-kynurenine metabolites but also HDL-C and CEs are important blood biomarkers for first-episode drug-naïve MDD patients. The present study sheds new light on early intervention in clinical practice in depression, and further clinical studies especially large-scale prospective studies are warranted.

The molecular aspects of oxidative & nitrosative stress and the tryptophan catabolites pathway (TRYCATs) as potential causes of depression

Depression is the most common mental disorder in the world. It is estimated that 350 million people suffer from depression worldwide. Depressive disorders will have become the second most frequent health problem globally by the year 2020, just behind ischemic heart disease. The causes of depressive disorders are not fully known. Previous studies showed that impaired tryptophan catabolites pathway, oxidative and nitrosative stress may play an important role in the pathogenesis of depression. Patients with depression have lower plasma levels of superoxide dismutase and glutathione peroxidise in comparison to controls. Moreover, depressed patients are characterized by decreased plasma levels of zinc, coenzyme Q10, albumin, uric acid, vitamin E and glutathione. Abnormal nitric oxidative production and nitric oxide synthase activity are also associated with depression. A dysfunction of the tryptophan catabolites pathway, indicated by increased levels of tryptophan 2,3-dioxygenase and indoleamine 2,3-dioxygenase, is also involved in the development of depression. Furthermore, increased levels of kynurenine and quinolinic acid might cause depression. Moreover, studies to date indicate that 8-oxyguanine, malondialdehyde, and 8-iso-prostaglandin F2α may serve as possible biomarkers. Additionally, regulation of defective mechanisms may provide a promising direction for the development of new and effective therapies.

Antioxidant uric acid in treated and untreated subjects with major depressive disorder: a meta-analysis and meta-regression

Pathophysiological mechanisms of major depressive disorder (MDD) seem to be associated with oxidative stress pathways and altered purinergic metabolism. We conducted a systematic review and meta-analysis to estimate if subjects with MDD might have reduced levels of antioxidant uric acid, considering also potential influence of antidepressant treatment. We searched the main Electronic Databases, identifying 14 studies that met our inclusion criteria. Meta-analyses were carried out generating pooled Hedges' g and mean differences (MDs), using random-effects models. Heterogeneity across studies and risk of publication bias were estimated using standard methods. Relevant sensitivity and meta-regression analyses were conducted. Subjects with MDD had levels of uric acid lower than healthy controls (Hedges' g = -0.30; p = 0.003). Overall between-study heterogeneity was high (I ² = 76.3%). The effect was significant among studies including drug naïve/free MDD individuals (Hedges' g = -0.55; p = 0.023), but not among those involving treated subjects (Hedges' g = -0.15; p = 0.062). Relevant quality- and heterogeneity-based sensitivity analyses, as well as meta-regressions, confirmed these findings. In addition, uric acid levels significantly, though inconsistently (I ² = 79.2%), increased after treatment (MD = +0.71 mg/dL; p < 0.001), regardless of follow-up duration (p = 0.518). Our meta-analysis shows that subjects with MDD have lower levels of uric acid. Since antidepressant treatment seems to influence this association, our findings support the hypothesis that uric acid levels may represent a state marker of MDD. Nevertheless, the potential role of additional factors that might clarify the nature of this association deserves further research.

A neuro-immune, neuro-oxidative and neuro-nitrosative model of prenatal and postpartum depression

A large body of evidence indicates that major affective disorders are accompanied by activated neuro-immune, neuro-oxidative and neuro-nitrosative stress (IO&NS) pathways. Postpartum depression is predicted by end of term prenatal depressive symptoms whilst a lifetime history of mood disorders appears to increase the risk for both prenatal and postpartum depression. This review provides a critical appraisal of available evidence linking IO&NS pathways to prenatal and postpartum depression. The electronic databases Google Scholar, PubMed and Scopus were sources for this narrative review focusing on keywords, including perinatal depression, (auto)immune, inflammation, oxidative, nitric oxide, nitrosative, tryptophan catabolites (TRYCATs), kynurenine, leaky gut and microbiome. Prenatal depressive symptoms are associated with exaggerated pregnancy-specific changes in IO&NS pathways, including increased C-reactive protein, advanced oxidation protein products and nitric oxide metabolites, lowered antioxidant levels, such as zinc, as well as lowered regulatory IgM-mediated autoimmune responses. The latter pathways coupled with lowered levels of endogenous anti-inflammatory compounds, including ω3 polyunsaturated fatty acids, may also underpin the pathophysiology of postpartum depression. Although increased bacterial translocation, lipid peroxidation and TRYCAT pathway activation play a role in mood disorders, similar changes do not appear to be relevant in perinatal depression. Some IO&NS biomarker characteristics of mood disorders are found in prenatal depression indicating that these pathways partly contribute to the association of a lifetime history of mood disorders and perinatal depression. However, available evidence suggests that some IO&NS pathways differ significantly between perinatal depression and mood disorders in general. This review provides a new IO&NS model of prenatal and postpartum depression.

Are there differences in lipid peroxidation and immune biomarkers between major depression and bipolar disorder: Effects of melancholia, atypical depression, severity of illness, episode number, suicidal ideation and prior suicide attempts

BACKGROUND

There is evidence that major depression (MDD) and bipolar disorder (BD) are accompanied by activated immune & oxidative (I&O) pathways.

METHODS

To compare I&O biomarkers between MDD and BD we assessed serum levels of thiobarbituric acid reactive substances (TBARS; a lipid peroxidation marker), soluble interleukin-2 receptor (sIL-2R), sIL-6R, IL-α, sIL-1R antagonist (sIL-1RA), tumor necrosis factor receptor 60kDa/80kDa (sTNFR60/R80) in 114 MDD and 133 BD patients, and 50 healthy controls. We computed z-unit weighted indices reflecting the 5 cytokine receptor levels (zCytR), cell-mediated immunity (zCMI) and I&O pathways (zCMI+TBARS).

RESULTS

There are no significant differences in biomarkers between MDD and BD. BD/MDD with atypical features is characterized by increased sIL-6R and TBARS, whereas melancholia is associated with higher TBARS and lower sTNFR60 levels. Severity of illness, as measured with the Hamilton Depression Rating Scale, is correlated with increased sIL-6R, sTNFR80, TBARS, zCytR and zCMI+TBARS. The number of episodes the year prior to blood sampling is positively associated with sTNFR80, TBARS, zCMI, zCMI+TBARS, while number of hospitalizations is positively associated with sIL-1RA. Prior suicidal attempts are associated with increased sIL-1RA, IL-1α, zCMI, TBARS and zCMI+TBARS, while TBARS is associated with current suicidal ideation.

CONCLUSIONS

There are no I&O biomarker differences between MDD and BD. Atypical depression is associated with increased IL-6 trans-signaling and lipid peroxidation. Severity of depression, number of episodes and suicidal attempts are associated with activated I&O pathways. Increased TBARS is the single best predictor of BD/MDD, atypical depression, melancholia and current suicidal ideation.

Saffron in the treatment of depression, anxiety and other mental disorders: Current evidence and potential mechanisms of action

BACKGROUND

Depression and anxiety are two common mental health problems with high economic and social costs. Currently, a number of treatments are available for patients with depression and anxiety disorders such as psychotherapy, electroconvulsive therapy and antidepressant drugs. Due to safety concerns, adverse effects, limited efficacy and low tolerability associated with many antidepressant and anti-anxiety medications, identification of novel agents with less toxicity and more favorable outcome is warranted.

METHODS

The current article provides a non-systematic review of the available in vitro, in vivo and clinical evidence on the efficacy, safety and mechanisms of action of saffron and its active ingredients in the treatment of anxiety, depression and other mental disorders.

RESULTS

Several interesting data have been reported about the antidepressant and anti-anxiety properties of saffron, the dried stigmas of Crocus sativus L., in several preclinical and clinical studies. In particular, a number of clinical trials demonstrated that saffron and its active constituents possess antidepressant properties similar to those of current antidepressant medications such as fluoxetine, imipramine and citalopram, but with fewer reported side effects.

CONCLUSION

Saffron may exert antidepressant effects and represents an efficacious and safe treatment.

Administration of Allium cepa L. bulb attenuates stress-produced anxiety and depression and improves memory in male mice

In view of anxiolytic, antidepressant and memory strengthen properties of Allium cepa (AC; onion) bulb in various investigations; we aimed to evaluate the useful effects of onion on single immobilization stress -induced biochemical and behavioral changes. Mice in test group were treated with AC powder (200 mg/kg/day), dissolved in water, while the control group were received drinking water for 14 days. After 14 days control and AC treated mice were further divided into unstressed and stressed groups. Animals in the stressed group were subjected to immobilization stress for 2 h. 24-h after the immobilization stress, behavioral activities were monitored. Immobilization stress-induced an anxiogenic behavior in mice subjected to elevated plus maze test (EPM) and light dark activity test (LDA). 2-h immobilization stress-induced depressive behavior in animals measured by forced swim test (FST). Administration of AC attenuated the immobilization stress-induced behavioral deficits. Highest memory performance was observed in stressed mice that were pre-treated with AC in Morris water maze (MWM). Brain lipid peroxidation, antioxidant enzymes (SOD, CAT, GPx) and acetylcholinesterase (AChE) activities were also estimated. Present study suggests a role of antioxidant enzymes in the attenuation of 2-h stress induced anxiety and depression, and enhanced cognitive function as well by AC. The findings therefore suggest that supplementation of AC may be beneficial in the treatment of anxiety, depression and enhancement of memory function.

Associations between severity of anxiety and clinical and biological features of major affective disorders

Patients with major affective disorders (MAFD) with comorbid anxiety show a greater functional impairment than those without anxiety. The aim of this study is to delineate the associations between severity of anxiety in MAFD, namely bipolar disorder (BD) and major depression (MDD), and MAFD characteristics and serum high-density lipoprotein (HDL)-cholesterol levels. Recruited were 82 participants with anxiety disoders and 83 without anxiety disoders, including 101 MAFD patients and 51 healthy controls. We used the Hamilton Anxiety Rating Scale (HAM-A) to measure severity of anxiety and made the diagnoses of posttraumatic stress disorder (PTSD), obsessive compulsive disorder (OCD), panic disorder (PD), generalized anxiety disorder (GAD) and phobias. The HAM-A score is significantly predicted by higher number of depressive episodes, GAD and phobias, childhood trauma, tobacco use disorder, metabolic syndrome and lowered HDL-cholesterol. Increased HAM-A scores are, independently from severity of depression, associated with lowered quality of life, increased disabilities and suicidal ideation. Lithium treatment significantly lowers HAM-A scores. It is concluded that severity of anxiety significantly worsens the phenomenology of MAFD. Therefore, treatments of MAFD should target increased severity of anxiety and its risk factors including low HDL-cholesterol, metabolic syndrome, childhood trauma and tobacco use disorder.

Natural regulatory IgM-mediated autoimmune responses directed against malondialdehyde regulate oxidative and nitrosative pathways and coupled with IgM responses to nitroso adducts attenuate depressive and physiosomatic symptoms at the end of term pregnancy

AIM

We aimed to delineate the effects of immunoglobulin (Ig)M-mediated autoimmune responses directed against malondialdehyde (MDA) and nitroso (SNO) adducts on nitro-oxidative stress and depressive and physiosomatic symptoms (DPSS) at the end of term.

METHODS

IgM responses to MDA, NO (nitroso) adducts formed by nitrosylation, and NO₂ tyrosine formed by nitration were measured as well as hydroperoxides (ferrous oxidation xylenol orange), advanced protein oxidation products (AOPP), and NO metabolite (NOx) levels in women at the end of term pregnancy and in normal controls.

RESULTS

IgM responses to MDA were significantly and inversely associated with AOPP, ferrous oxidation xylenol orange, and NOx and DPSS. IgM responses to NO adducts were significantly and inversely associated with DPSS and positively with NOx levels. There were significant associations between IgM responses to MDA, NO adducts, and NO₂ tyrosine. The DPSS score was predicted by AOPP and a lifetime history of premenstrual syndrome (both positively) and IgM responses to NO adducts (inversely). Furthermore, 71.8% of the variance in the index of nitro-oxidative stress was explained by lowered IgM responses to MDA, antioxidant levels (zinc, total radical trapping parameter), and inflammatory mediators.

CONCLUSION

Lowered levels of IgM responses to MDA during pregnancy are accompanied by a reduced regulation of nitro-oxidative processes thereby explaining increased oxidative and nitrosative stress biomarkers in association with DPSS. IgM responses to NO adducts, which reflect nitrosylation as a consequence of increased NO production, regulate DPSS symptoms at the end of term and are a trait marker of major depression. IgM responses to MDA are a key part of the compensatory anti-inflammatory responses system.

Add-on Treatment with Curcumin Has Antidepressive Effects in Thai Patients with Major Depression: Results of a Randomized Double-Blind Placebo-Controlled Study

Activation of immune-inflammatory and oxidative-nitrosative (IO&NS) stress pathways plays a role in major depression (MDD). Evidence suggests that curcumin (500-1000 mg/day), a polyphenol with strong anti-IO&NS properties, may have efficacy either as monotherapy or as an adjunctive treatment for depression. Further controlled trials with extended treatment periods (> 8 weeks) and higher curcumin doses are warranted. This 12-week study was carried out to examine the effects of adjunctive curcumin for the treatment of MDD. In this double-blind, placebo-controlled trial, 65 participants with MDD were randomized to receive either adjunctive curcumin (increasing dose from 500 to 1500 mg/day) or placebo for 12 weeks. Four weeks after the active treatment phase, a follow-up visit was conducted at week 16. Assessments of the primary, i.e., the Montgomery-Asberg Depression Rating Scale (MADRS), and secondary, i.e., the Hamilton Anxiety Rating Scale (HAM-A), outcome measures were rated at baseline and 2, 4, 8, 12, and 16 weeks later. Curcumin was more efficacious than placebo in improving MADRS scores with significant differences between curcumin and placebo emerging at weeks 12 and 16. The effects of curcumin were more pronounced in males compared to females. There were no statistically significant treatment-emerging adverse effects and no significant effects of curcumin on blood chemistry and ECG measurements. Adjunctive curcumin has significant antidepressant effects in participants with MDD as evidenced by significant benefits occurring 12 and 16 weeks after treatment initiation. Curcumin administration was safe and well-tolerated even when combined with antidepressants. Future trials should include treatment-by-sex interactions to examine putative antidepressant effects of immune-modifying compounds.

Linking the biological underpinnings of depression: Role of mitochondria interactions with melatonin, inflammation, sirtuins, tryptophan catabolites, DNA repair and oxidative and nitrosative stress, with consequences for classification and cognition

The pathophysiological underpinnings of neuroprogressive processes in recurrent major depressive disorder (rMDD) are reviewed. A wide array of biochemical processes underlie MDD presentations and their shift to a recurrent, neuroprogressive course, including: increased immune-inflammation, tryptophan catabolites (TRYCATs), mitochondrial dysfunction, aryl hydrocarbonn receptor activation, and oxidative and nitrosative stress (O&NS), as well as decreased sirtuins and melatonergic pathway activity. These biochemical changes may have their roots in central, systemic and/or peripheral sites, including in the gut, as well as in developmental processes, such as prenatal stressors and breastfeeding consequences. Consequently, conceptualizations of MDD have dramatically moved from simple psychological and central biochemical models, such as lowered brain serotonin, to a conceptualization that incorporates whole body processes over a lifespan developmental timescale. However, important hubs are proposed, including the gut-brain axis, and mitochondrial functioning, which may provide achievable common treatment targets despite considerable inter-individual variability in biochemical changes. This provides a more realistic model of the complexity of MDD and the pathophysiological processes that underpin the shift to rMDD and consequent cognitive deficits. Such accumulating data on the pathophysiological processes underpinning MDD highlights the need in psychiatry to shift to a classification system that is based on biochemical processes, rather than subjective phenomenology.

Thioredoxin is not a marker for treatment-resistance depression but associated with cognitive function: An rTMS study

Elevated oxidative stress is known to play an important role in development of depression and cognitive dysfunction. To date, thioredoxin (TRX), an antioxidant protein, has been investigated as a marker for psychiatric disorders such as schizophrenia, bipolar disorder and autism but its relationship with depression is yet to be unknown. The aim of this study is to detect the TRX levels in patients with treatment-resistant depression (TRD), analyse the effect of rTMS (repetitive transcranial magnetic stimulation) application on TRX levels and display the relationship of TRX with cognitive areas. This study included 27 treatment-resistant unipolar depression patients and 29 healthy subjects. Patients were evaluated by Hamilton Depression Scale (HDRS), Hamilton Anxiety Scale (HARS) and Montreal Cognitive Assessment (MoCA) before and after rTMS application. 23 of TRD patients were applied high-frequency rTMS over left DLPFC for 2 to 4weeks and plasma TRX levels of patients and healthy subjects were measured. No significant difference was determined between the TRX levels of patients and healthy subjects (p>0.05). After rTMS application there were significant decrease in severity of depression (p<0.001) and anxiety (p<0.001), and explicit improvement in cognitive areas (delayed memory, visual-spatial/executive abilities and language points) (all p<0.05). No difference was detected in TRX levels of the patients after rTMS application (p>0.005). High language scores of the patients were found to be associated with high TRX levels (p<0.005). Our study indicates that TRX levels cannot be used as a marker for TRD or rTMS treatment in TRD. In spite of this TRX levels have a positive correlation with language functions of the patients of TRD. More extensive studies are required to clarify the mechanism of action of TRX and the effect of TRX on cognitive functions.

Uric acid in major depressive and anxiety disorders

BACKGROUND

Uric acid has neuroprotective effects, owing to its antioxidant properties. Lowered antioxidant capacity, causing increased oxidative stress, may be involved in affective disorders and might be altered by antidepressants. This study investigated the association of plasma uric acid, the greatest contributor to blood antioxidant capacity, with major depressive disorder (MDD) and anxiety disorders.

METHODS

Data were from the Netherlands Study of Depression and Anxiety including patients with current (N = 1648), remitted (N = 609) MDD and/or anxiety disorders (of which N = 710 antidepressant users) and 618 controls. Diagnoses were established with the Composite International Diagnostic Interview. Symptom severity was assessed with the Inventory of Depressive Symptoms-Self Report, Beck Anxiety Inventory and Fear Questionnaire. Uric acid was measured in plasma. Analyses were adjusted for sociodemographic, health and lifestyle variables.

RESULTS

Plasma uric acid adjusted mean levels were lower in current MDD and/or anxiety disorder(s) (289μmol/l) compared to remitted disorders (298μmol/l, p < .001) and controls (299μmol/l, p < .001; Cohen's d .10). This finding was independent of antidepressant use. Depressive (β-.05, p = .0012), anxiety (β-.04, p = .009) and phobic (β-.03, p = .036) symptom severity, and symptom duration (β-.04, p = .009) were negatively associated with uric acid.

LIMITATIONS

Limitations include the lack of data on dietary intake which could be a potential confounding factor. From these cross-sectional findings, the association between uric acid and psychopathology cannot be inferred to be causal.

CONCLUSION

This large scale study finds plasma uric acid levels are lower in current, but not remitted, MDD and/or anxiety disorders, according to a dose-response gradient. This suggests the involvement of decreased antioxidant status in affective disorders, and points to their potential as an avenue for treatment.

Activated neuro-oxidative and neuro-nitrosative pathways at the end of term are associated with inflammation and physio-somatic and depression symptoms, while predicting outcome characteristics in mother and baby

OBJECTIVES

To examine oxidative & nitrosative stress (O&NS) biomarkers at the end of term in relation to perinatal affective symptoms, neuro-immune biomarkers and pregnancy-related outcome variables.

METHODS

We measured plasma advanced oxidation protein products (AOPP), nitric oxide metabolites (NOx), total radical trapping antioxidant parameter (TRAP), -sulfhydryl (-SH), peroxides (LOOH) and paraoxonase (PON)1 activity in pregnant women with and without prenatal depression and non-pregnant controls.

RESULTS

Pregnancy is accompanied by significantly increased AOPP and NOx, and lowered TRAP, -SH and LOOH. Increased O&NS and lowered LOOH and -SH levels are associated with prenatal depressive and physio-somatic symptoms (fatigue, pain, dyspepsia, gastro-intestinal symptoms). Increased AOPP and NOx are significantly associated with lowered -SH, TRAP and zinc, and with increased haptoglobin and C-reactive protein levels. Increased O&NS and lowered TRAP and PON 1 activity, at the end of term predict mother (e.g. hyperpigmentation, labor duration, caesarian section, cord length, breast milk flow) and baby (e.g. sleep and feeding problems) outcome characteristics.

CONCLUSIONS

Pregnancy is accompanied by interrelated signs of O&NS, lowered antioxidant defenses and activated neuro-immune pathways. Increased O&NS at the end of term is associated with perinatal depressive and physio-somatic symptoms and may predict obstetric and behavioral complications in mother and baby.

Early life experience contributes to the developmental programming of depressive-like behaviour, neuroinflammation and oxidative stress

This study used an animal model of depression induced by maternal care deprivation (MCD) to investigate whether depressive behaviour, neuroinflammation and oxidative stress were underlying factors in developmental programming after early life stress. At postnatal days (PND) 20, 30, 40, and 60, individual subsets of animals were evaluated in behavioural tests and then euthanized to assess cytokine levels and oxidative stress parameters in the prefrontal cortex (PFC), hippocampus and serum. The results showed that MCD did not induce behavioural changes at PND 30 and 40. However, at PND 20 and 60, the rats displayed a depressive-like behaviour in the forced swimming test, without changes in locomotor spontaneous activity. In the brain and serum, the levels of pro-inflammatory cytokines (interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α)) were increased, and the anti-inflammatory cytokine (interleukin-10) level was reduced throughout developmental programming (PND 20, 30, 40 and 60). Protein carbonyl levels increased in the brain at PND 30, 40 and 60. Superoxide dismutase (SOD) activity was decreased during all developmental programming phases evaluated in the brain. Catalase (CAT) activity was decreased at PND 20, 40 and 60 in the brain. Our results revealed that "critical episodes" in early life stressful events are able to induce behavioural alterations that persist into adulthood and can stimulate inflammation and oxidative damage in both central and peripheral systems, which are required for distinct patterns of resilience against psychiatric disorders later in life.

Depressive symptoms are associated with leukocyte telomere length in American Indians: findings from the Strong Heart Family Study

Patients with depression have an increased risk for many aging-related disorders, but the biological mechanisms underlying this link remain to be determined. Here we examined the association between depressive symptoms and leukocyte telomere length (LTL), a marker of biological aging, among 2,175 American Indians participating in the Strong Heart Family Study. Depressive symptoms were assessed by the Center for Epidemiologic Studies of Depression Scale (CES-D), which was categorized into four levels: none (< 10), mild (10-15), moderate (16-24), and severe (> 24). LTL (T/S ratio) was quantified by qPCR. The association between depressive symptoms and LTL was examined by multivariate generalized estimating equation models, adjusting for sociodemographic factors, lifestyle factors, and chronic conditions. Results showed that individuals with a higher level of depressive symptoms had shorter LTL. Specifically, LTL in participants reporting none, mild, moderate, and severe depressive symptoms were 1.000, 0.999, 0.988, and 0.966, respectively (P for trend = 0.0278). Moreover, gender appears to modulate the effect of reported depressive symptoms that fall in the severe range (CES-D > 24) on LTL (P for interaction = 0.0346). Our results suggest that depressive symptoms may accelerate biological aging through pathways beyond traditional risk factors in American Indians.

Within-Subject Reliability and between-Subject Variability of Oxidative Stress Markers in Saliva of Healthy Subjects: A Longitudinal Pilot Study

The present study evaluated diurnal variations and day-to-day fluctuations of salivary oxidative stress (OS) markers in healthy adult individuals. Whole unstimulated saliva was collected at 2 time intervals over 3 consecutive days. Glutathione peroxidase (GPX), superoxide dismutase (SOD), total antioxidant capacity (TAC), and uric acid (UA) were analyzed using spectrophotometric methods, while 8-hydroxydeoxyguanosine (8-OHdG) and malondialdehyde (MDA) were determined using immunoassays. No significant differences for salivary OS markers between men and women were observed. For all examined OS markers, no significant day-to-day variations were demonstrated. Significant diurnal variations were found in salivary GPX, TAC and MDA levels. For SOD, TAC, GPX, and UA, good-to-moderate intraindividual coefficients of variations (CVs) were observed in more than 75% of the subjects. For MDA and 8-OHdG, intraindividual CVs > 35% were observed in 60% and 40% of the subjects, respectively. Between-subject variance was wide for all examined OS markers (CV% 30.08%–85.70%). Due to high intraindividual variability in the salivary concentrations of MDA and 8-OHdG, those markers cannot be reliably verified based on single measurements and multiple measurements over several days would provide more reliable information. Salivary SOD, TAC, GPX, and UA proved stable across three days of measurement. Trial Registration. ClinicalTrials.gov NCT03029494. Registered on 2017-01-19.

Lipid Peroxidation and Immune Biomarkers Are Associated with Major Depression and Its Phenotypes, Including Treatment-Resistant Depression and Melancholia

To examine immune-inflammatory and oxidative (I&O) biomarkers in major depression (MDD) and its related phenotypes, we recruited 114 well-phenotyped depressed patients and 50 healthy controls and measured serum levels of interleukin (IL)-1α, soluble IL-1 receptor antagonist (sIL-1RA), soluble IL-2 receptor (sIL-2R), soluble IL-6 receptor (sIL-6R), soluble tumor necrosis factor receptor 60 and 80 kDa (sTNF-R1/R2), and thiobarbituric acid reactive substances (TBARS). Obtained results indicate that MDD is characterized by increased sIL-1RA, sTNF-R1, and TBARS concentrations. Melancholic depression is associated with increased sIL-6R but lowered IL-1α levels. A current episode of depression is accompanied by significantly increased sIL-6R compared to the remitted state. Treatment-resistant depression (TRD) is accompanied by increased sIL-6R and TBARS but lowered sTNF-R2 levels compared to non-TRD patients. These immune markers are not significantly correlated with Hamilton Depression Rating Scale (HDRS), Montgomery-Asberg Depression Scale (MADRS), number episodes, or age at onset. Our findings show that increased sIL-1RA, sTNF-R1, and TBARS levels may be trait markers of depression, while increased sIL-6R levels may be a state marker of melancholia and an acute phase of depression. MDD is accompanied by increased lipid peroxidation and simultaneous activation of immune pathways, and the compensatory anti-inflammatory reflex system (CIRS). TRD is characterized by highly increased oxidative stress and probably increased TNFα and IL-6 trans-signalling. Novel treatments for major depression should target oxidative stress pathways, while new treatments for TRD should primary target lipid peroxidation and also activated immune-inflammatory pathways.

Diminished stress resistance and defective adaptive homeostasis in age-related diseases

Adaptive homeostasis is defined as the transient expansion or contraction of the homeostatic range following exposure to subtoxic, non-damaging, signaling molecules or events, or the removal or cessation of such molecules or events (Mol. Aspects Med. (2016) 49, 1-7). Adaptive homeostasis allows us to transiently adapt (and then de-adapt) to fluctuating levels of internal and external stressors. The ability to cope with transient changes in internal and external environmental stress, however, diminishes with age. Declining adaptive homeostasis may make older people more susceptible to many diseases. Chronic oxidative stress and defective protein homeostasis (proteostasis) are two major factors associated with the etiology of age-related disorders. In the present paper, we review the contribution of impaired responses to oxidative stress and defective adaptive homeostasis in the development of age-associated diseases.

Assessing the serum concentration levels of NT-4/5, GPX-1, TNF-α, and l-arginine as biomediators of depression severity in first depressive episode patients with and without posttraumatic stress disorder

BACKGROUND

Neurotrophin-4/5 (NT-4/5) and glutathione peroxidase-1 (GPX-1) have been shown to play a major role in neuronal processes including depression and posttraumatic stress disorder (PTSD). They protect the body from oxidative damage by affecting neuronal growth, development and plasticity. The aim of the study was to evaluate the concentrations of NT-4/5, GPX-1, tumor necrosis factor-α (TNF-α), and l-arginine in patients suffering from varying levels of depression severity, PTSD, and depression comorbid with PTSD.

METHODS

The study involved 460 participants, 360 of whom were diagnosed with different types of depressive episodes. They included: 60 patients with mild depression (MD), 60 patients with moderate depression (MOD), 60 patients with severe depression (SeD), 60 patients with MD and PTSD (MD+PTSD), 60 patients with MOD and PTSD (MOD+PTSD), 60 patients with SeD and PTSD (SeD+PTSD), and 60 patients with PTSD alone. Each group of 60 subjects comprised 30 females and 30 males. The control group comprised 40 subjects. The 10th revision of the International Statistical Classification of Diseases and Related Health Problems was utilized to diagnose depression and PTSD. At 7a.m. blood samples were collected and serum NT-4/5, GPX-1, TNF-α and l-arginine concentrations were assessed using the ELISA method.

RESULTS

Depressive episodes with and without PTSD and PTSD alone became more severe as the levels of TNF-α, l-arginine increased and the levels of NT-4/5, GPX-1 decreased.

CONCLUSION

l-arginine, TNF-α, NT-4/5 and GPX-1 can be markers of depression severity in both males and females with first depressive episode with or without posttraumatic stress disorder.

Molecular Mechanisms Underlying the Anti-depressant Effects of Resveratrol: a Review

Major depression is a public health problem, affecting 121 million people worldwide. Patients suffering from depression present high rates of morbidity, causing profound economic and social impacts. Furthermore, patients with depression present cognitive impairments, which could influence on treatment adherence and long-term outcomes. The pathophysiology of major depression is not completely understood yet but involves reduced levels of monoamine neurotransmitters, bioenergetics, and redox disturbances, as well as inflammation and neuronal loss. Treatment with anti-depressants provides a complete remission of symptoms in approximately 50% of patients with major depression. However, these drugs may cause side effects, as sedation and weight gain. In this context, there is increasing interest in studies focusing on the anti-depressant effects of natural compounds found in the diet. Resveratrol is a polyphenolic phytoalexin (3,4',5-trihydroxystilbene; C₁₄H₁₂O₃; MW 228.247 g/mol) and has been found in peanuts, berries, grapes, and wine and induces anti-oxidant, anti-inflammatory, and anti-apoptotic effects in several mammalian cell types. Resveratrol also elicits anti-depressant effects, as observed in experimental models using animals. Therefore, resveratrol may be viewed as a potential anti-depressant agent, as well as may serve as a model of molecule to be modified aiming to ameliorate depressive symptoms in humans. In the present review, we describe and discuss the anti-depressant effects of resveratrol focusing on the mechanism of action of this phytoalexin in different experimental models.

Evidence for Inflammation-Associated Depression

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

Increased levels of ascorbic acid in the cerebrospinal fluid of cognitively intact elderly patients with major depression: a preliminary study

Major depressive disorder (MDD) in the elderly is a risk factor for dementia, but the precise biological basis remains unknown, hampering the search for novel biomarkers and treatments. In this study, we performed metabolomics analysis of cerebrospinal fluid (CSF) from cognitively intact elderly patients (N = 28) with MDD and age- and gender-matched healthy controls (N = 18). The CSF levels of 177 substances were measured, while 288 substances were below the detection limit. Only ascorbic acid was significantly different, with higher levels in the MDD group at baseline. There were no correlations between CSF ascorbic acid levels and clinical variables in MDD patients at baseline. At the 3-year follow-up, there was no difference of CSF ascorbic acid levels between the two groups. There was a negative correlation between CSF ascorbic acid and CSF amyloid-β₄₂ levels in all subjects. However, there were no correlations between ascorbic acid and other biomarkers (e.g., amyloid-β₄₀, total and phosphorylated tau protein). This preliminary study suggests that abnormalities in the transport and/or release of ascorbic acid might play a role in the pathogenesis of late-life depression.

Salvia (Sage): A Review of its Potential Cognitive-Enhancing and Protective Effects

Genus Salvia, commonly known as sage, is the largest genus in the Lamiaceae family. It comprises many species traditionally used as brain-enhancing tonics. In vitro and animal studies have confirmed that several Salvia species contain a large array of active compounds that may enhance cognitive activity and protect against neurodegenerative disease. In this review, the active constituents in plants belonging to the genus Salvia are summarised, and their influence on pharmacodynamics pertinent to cognitive activity are detailed. In particular, the effects of plants belonging to the genus Salvia and their constituents on cognitive skills including memory, attention and learning are detailed. Their potential effects in dementia, including Alzheimer’s disease, are also examined. Completed human trials are summarised, and factors influencing the potency of Salvia plants are covered. Finally, directions for future research are proposed to enhance our understanding of the potential health benefits of Salvia plants.

Increased Root Canal Endotoxin Levels are Associated with Chronic Apical Periodontitis, Increased Oxidative and Nitrosative Stress, Major Depression, Severity of Depression, and a Lowered Quality of Life

Evidence indicates that major depression is accompanied by increased translocation of gut commensal Gram-negative bacteria (leaky gut) and consequent activation of oxidative and nitrosative (O&NS) pathways. This present study examined the associations among chronic apical periodontitis (CAP), root canal endotoxin levels (lipopolysaccharides, LPS), O&NS pathways, depressive symptoms, and quality of life. Measurements included advanced oxidation protein products (AOPP), nitric oxide metabolites (NOx), lipid peroxides (LOOH), -sulfhydryl (SH) groups, total radical trapping antioxidant parameter (TRAP), and paraoxonase (PON)1 activity in participants with CAP, with and without depression, as well as healthy controls (no depression, no CAP). Root canal LPS levels were positively associated with CAP, clinical depression, severity of depression (as measured with the Hamilton Depression Rating Scale (HDRS) and the Beck Depression Inventory) and O&NS biomarkers, especially NOx and TRAP. CAP-related depression was accompanied by increased levels of NOx, LOOH, AOPP, and TRAP. In CAP participants, there was a strong correlation (r = 0.734, p < 0.001) between root canal LPS and the HDRS score. There were significant and positive associations between CAP or root canal endotoxin with the vegetative and physio-somatic symptoms of the HDRS as well as a significant inverse association between root canal endotoxin and quality of life with strong effects on psychological, environmental, and social domains. It is concluded that increased root canal LPS accompanying CAP may cause depression and a lowered quality of life, which may be partly explained by activated O&NS pathways, especially NOx thereby enhancing hypernitrosylation and thus neuroprogressive processes. Dental health and "leaky teeth" may be intimately linked to the etiology and course of depression, while significantly impacting quality of life.

Oxidative stress in major depressive and anxiety disorders, and the association with antidepressant use; results from a large adult cohort

BACKGROUND

Oxidative stress has been implicated in the pathophysiology of major depressive disorder (MDD) and anxiety disorders and may be influenced by antidepressant use. This study investigated the association of oxidative stress, measured by plasma levels of F2-isoprostanes and 8-hydroxy-2'-deoxyguanosine (8-OHdG) reflecting oxidative lipid and DNA damage respectively, with MDD, anxiety disorders and antidepressant use in a large cohort.

METHOD

Data was derived from the Netherlands Study of Depression and Anxiety including patients with current (N = 1619) or remitted (N = 610) MDD and/or anxiety disorder(s) (of which N = 704 antidepressant users) and 612 controls. Diagnoses were established with the Composite International Diagnostic Interview. Plasma 8-OHdG and F2-isoprostanes were measured using LC-MS/MS. ANCOVA was performed adjusted for sampling, sociodemographic, health and lifestyle variables.

RESULTS

F2-isoprostanes did not differ between controls and patients, or by antidepressant use. Patients with current disorders had lower 8-OHdG (mean 42.1 pmol/l, 95% CI 40.4-43.8) compared to controls (45.0 pmol/l, 95% CI 42.9-47.2; p < 0.001) after adjustment for sampling, sociodemographics and lifestyle, but these differences disappeared after further adjustment for antidepressant use (p = 0.562). Antidepressant users had lower 8-OHdG levels (38.2 pmol/l, 95% CI 36.5-39.9) compared to controls (44.9 pmol/l, 95% CI 43.2-46.6; Cohen's d = 0.21, p < 0.001). Results for 8-OHdG were comparable across disorders (MDD and/or anxiety disorders), and all antidepressant types (SSRIs, TCAs, other antidepressants).

CONCLUSION

Contrary to previous findings this large-scale study found no increased oxidative stress in MDD and anxiety disorders. Antidepressant use was associated with lower oxidative DNA damage, suggesting antidepressants may have antioxidant effects.

Biological Aging and the Future of Geriatric Psychiatry

Advances in understanding the biological bases of aging have intellectually revitalized the field of geriatric psychiatry and broadened its scope to include promoting successful aging and studying resilience factors in older adults. To describe the process by which this paradigm shift has occurred and illustrate its implications for treatment and research of late-life brain disorders, late-life depression is discussed as a prototype case. Prior phases of geriatric psychiatry research were focused on achieving depressive symptom relief, outlining pharmacokinetic and pharmacodynamic differences between older and younger adults, and identifying moderators of treatment response. Building on this work, current geriatric psychiatry researchers have begun to disentangle the etiologic complexity in late-life depression by focusing on the causative aging-related processes involved, identifying both neurobiological and behavioral intermediates, and finally delineating depression subtypes that are distinguishable by their underlying biology and the treatment approach required. In this review, we discuss several age-related processes that are critical to the development of late-life mood disorders, outline implications of these processes for the clinical evaluation and management of later-life psychiatric disorders, and finally put forth suggestions for better integrating aging and developmental processes into the National Institute of Mental Health's Research Domain Criteria.

Serum uric acid and impaired cognitive function in community-dwelling elderly in Beijing

The relationship between serum uric acid (sUA) and cognitive function is contradictory. This study assessed the association between sUA and cognitive impairment in 10,039 community-dwelling subjects aged ≥55years living in Beijing, China. Participants underwent determination of sUA and an evaluation of cognitive function using the scholarship-adjusted Mini-Mental State Examination (MMSE): MMSE ≤17 for illiterates; MMSE≤20 for primary school graduates (≥6years of education); and MMSE≤24 for junior school graduates or above (≥9years of education). Among the 10016 persons with valid MMSE scores, the prevalence of cognitive impairment was 9.14%. A multivariate logistic regression model including demographic, clinical and genetic parameters was performed to assess the relationship between sUA and cognitive impairment. Persons with cognitive impairment had lower sUA levels than those with normal cognitive function: (302.30±82.80 vs. 312.20±84.01μmol/L, p=0.001). After adjusting for age, sex, lifestyle, relevant diseases and the apolipoprotein E (APOE) ε4 allele, stepwise logistic regression showed that participants with higher levels of sUA had a lower risk of cognitive impairment (hazard ratio (HR): 0.78; 95% confidence interval (CI): 0.62-0.96; p=0.022). In this baseline cross-sectional population-based sample, high levels of sUA were associated with a decreased risk of cognitive impairment.

Antidepressant-like effect of the saponins part of ethanol extract from SHF

ETHNOPHARMACOLOGICAL RELEVANCE

Suanzaorenhehuan Formula (SHF) has been used for treating depression-like disorders for many years in China. The saponins part of the SHF (SSHF) extract was the antidepressant effective component.

AIM OF STUDY

To investigate the antidepressant-like effect of SSHF and its possible mechanisms.

MATERIALS AND METHODS

Experimental approaches including the forced swim test (FST), the tail suspension test (TST) and unpredictable chronic mild stress (UCMS) were used to evaluate the effects of SSHF. The possible mechanisms were explored by measuring monoamine neurotransmitter in mice frontal cortex and hippocampus, testing monoamine oxidase enzyme (MAO) activities, antioxidant enzyme activities and free radicals levels in the brains of UCMS-exposed mice.

RESULTS

The results showed that SSHF (10, 20, 40mg/kg) significantly decreased the immobility period in FST and TST in mice after two-week treatment. Whereas, SSHF had no significant effect on locomotor activity in mice. It was also found that the serotonin (5-HT) and noradrenaline (NE) levels in the hippocampus and frontal cortex were significantly increased only in 40mg/kg SSHF treated mice. In addition, SSHF (10, 20, 40mg/kg) significantly inhibited monoamine oxidase-A (MAO-A) and monoamine oxidase-B (MAO-B) after 21-day UCMS exposure. SSHF (10, 20, 40mg/kg) significantly decreased the nitrous oxide (NO) levels, and increased the activities of total antioxidant capability (T-AOC), glutathione peroxidase (GSH-PX), and catalase (CAT) in different degrees in the brains of UCMS-exposed mice.

CONCLUSIONS

Our results suggested that SSHF may effectively produce an antidepressant-like effect, which appeared to involve the serotonergic, noradrenergic, monoamine oxidase enzyme and antioxidant systems.

Probable preventive effects of placenta from oxidative stress; Evaluation of total antioxidant status, total oxidant status and oxidative stress index in fetal cord blood during the delivery

Depression in pregnancy may have negative effects on birth outcomes. It may also effect the intrauterine environment of the fetus. The umbilical cord is the conduit between the fetus and placenta, and functions in the transport between fetus and mother. Investigating biochemical parameters in fetal cord blood (FCB) during delivery may be helpful to understanding to what the fetus is exposed to, at least in the last trimester. In this study, we aimed to investigate total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) in the FCB of depressed mothers and healthy controls during delivery. Our study included 33 depressed mothers and 37 healthy controls. TAS, TOS, and OSI were measured according to Erel's method. We found that TAS, TOS, and OSI levels were similar in patients and healthy controls; however, the birth weights of depressed patients were significantly lower than those of healthy controls. Our results suggest that the placental barrier may prevent from oxidative stress. Future studies should include blood samples collected simultaneously from mothers during delivery.

Evaluation of malondialdehyde, superoxide dismutase and catalase activity and their diagnostic value in drug naïve, first episode, non-smoker major depression patients and healthy controls

Major depression is a most frequent disorder, its diagnosis depends on patient interview, and yet we do not have a reliable biomarker for depression. Oxidative stress is defined as increase in oxidation or decrease is antioxidant defense mechanisms. Here, we aimed to investigate malondialdehyde (MDA), superoxide dismutase (SOD) and catalase (CAT) activity and their diagnostic performance in depressed patients and healthy controls. We collected blood samples from 50 patients and 50 controls. We found MDA levels were significantly higher in the patients than controls, with medians at 4.04nmol/mg and 1.64nmol/mg, respectively, p<0.001. SOD activity was significantly decreased in depressed patients than healthy controls, with means at 143.50U/mg and 298.12U/mg, respectively, p<0.001. CAT activity was similar in both groups, p=0.517. ROC analysis showed good diagnostic value for MDA and SOD, with the area under the curve at 1.0 for both. We found high correlation between SOD and Ham-D scores (r=0.747, p<0.0001) and between MDA and Ham-D scores (r=0.785, p<0.0001). Overall, these results demonstrate that oxidative stress is increased in depressed patients. MDA increase seem to be a common finding for major depression. We believe MDA could be a good biomarker candidate for major depression, but not SOD. Future studies should focus on the diagnostic value of MDA in larger samples.

Effect of Musa sapientum Stem Extract on Animal Models of Depression

Background:

Musa sapientum, the banana plant, has shown to possess antioxidant activity in previous studies. Oxidative stress has been linked to the pathogenesis of major depressive disorder (MDD) with evidence of increased serum levels of oxidative stress biomarkers in MDD patients.

Objective:

The present study aimed to evaluate the antidepressant activity of M. sapientum stem extract (MSSE) in experimental models in mice.

Materials and Methods:

Forced swim test (FST) and tail suspension test (TST) were carried out in five different groups (n = 6/group) of mice. The vehicle, standard drug, and the three test groups were orally administered distilled water (10 mL/kg), fluoxetine (25 mg/kg), and incremental doses of 25, 50, and 100 mg of MSSE, respectively, 45 min prior to the experiment.

Results:

On FST, the duration of immobility in control group, which was 161.5 ± 6.78 (in seconds, mean ± standard error of mean [SEM]), decreased to 149.33 ± 2.70 (25 mg/kg MSSE), 120.17 ± 8.35 (50 mg/kg MSSE), and 45.17 ± 4.11 (100 mg/kg MSSE) in the treated groups. On TST, the duration of immobility in control group, which was 173.83 ± 12.65 (mean ± SEM), decreased to 163.17 ± 6.91 (25 mg/kg MSSE), 139.0 ± 5.9 (50 mg/kg MSSE), and 124.0 ± 4.42 (100 mg/kg MSSE) in the treated groups. The difference in the duration of immobility was statistically significant at middle and higher doses, i.e. 50 and 100 mg/kg MSSE (P < 0.05) respectively, when compared with the control group in both the tests.

Conclusion:

A significant antidepressant-like activity was found in MSSE, which could be a potential natural compound for use in depression.

SUMMARY

The five groups – vehicle, standard drug, and the three test groups were administered distilled water (10 mL/kg), fluoxetine (25 mg/kg), and incremental doses of 25, 50, and 100 mg of Musa sapientum stem extract (MSSE), respectively

The duration of immobility decreased in the treated groups as compared to the control group on both, forced swim and tail suspension, tests

The difference in the duration of immobility was statistically significant at middle and higher doses, i.e., 50 and 100 mg/kg MSSE (P < 0.05), when compared with the control group in both the tests.

Abbreviations Used: MDD: Major depressive disorder; MSSE: Musa sapientum stem extract; FST: Forced swim test; TST: Tail suspension test; GSH: Glutathione, MDA: Malondialdehyde; SOD: Superoxide dismutase