Polyunsaturated Fatty Acids in Perinatal Depression: A Systematic Review and Meta-analysis

Targeting Divergent Pathways in the Nutritional Management of Depression

The nutritional management of depression has long been discussed, due to the perceived benefit of a nutritional product having less side effects than pharmaceutical agents. Candidate nutrients for managing depression include vitamin D, B vitamins, tryptophan, branch chain amino acids, probiotics, omega-3 fatty acids, folate/methylfolate (also known as vitamin B9), and s-adenosylmethionine. This paper provides a narrative review of three nutrients which have significant scientific support for the management of depression. A deficiency in each nutrient is associated with depression, and interventional studies indicate that the correction of the nutritional deficiency may provide clinical benefit. We present epidemiological evidence, a mechanistic explanation and a review of interventional studies for these nutrients. Finally, relevant nutritional guidelines are presented with their conclusion for the role of each nutrient in the management of depression.

Association between polyunsaturated fatty acids and depression in women with infertility: a cross-sectional study based on the National Health and Nutrition Examination Survey

Background

Identifying possible influencing factors is crucial for the depression symptoms of women experiencing infertility. This study aims to explore the association between polyunsaturated fatty acids (PUFAs) and the odds of depression symptoms in women experiencing infertility.

Methods

This is a cross-sectional study based on the National Health and Nutrition Examination Survey (NHANES). PUFA intake was obtained through a 24-h dietary recall interview. Depression symptoms were defined using the Patient Health Questionnaire-9 (PHQ-9) with a score of ≥10 points or as taking antidepressants. The association between PUFA and depression was assessed using a logistic regression model by calculating the odds ratio (OR) with 95% confidence interval (CI). Subgroup analysis was carried out based on menopausal status and female hormone use.

Results

There were 725 participants included for analysis. After adjusting the covariables, lower odds of depression symptoms were found in patients with the intake of omega-3 PUFA (OR = 0.48, 95% CI: 0.24-0.96) and omega-6 PUFA (OR = 0.24, 95% CI: 0.14-0.42) in the second tertile (T2) in comparison to the first tertile (T1). The intake of α-linolenic (ALA) (OR = 0.48, 95% CI: 0.23-0.97) and linoleic acid (OR = 0.24, 95% CI: 0.14-0.41) in T2 was also found to be related to the reduced odds of depression symptoms in comparison to T1.

Conclusions

Our findings suggest a potential association between moderate omega-3 and omega-6 PUFA intake and a reduced risk of depression symptoms in women experiencing infertility. This implies that clinicians might find it useful to consider dietary advice that includes PUFA-rich foods as part of a broader strategy to address mental health in this patient group. However, further research is needed to confirm these preliminary findings and to establish the optimal levels of PUFA intake for mental health benefits.

The gut microbiome from middle-aged women with depression modulates depressive-like behaviors and plasma fatty acid metabolism in female middle-aged mice

BACKGROUND

Intestinal dysbacteriosis has frequently been involved in the context of depression. Nonetheless, only scant information is available about the features and functional changes of gut microbiota in female middle-aged depression (MAD).

OBJECTIVE

This study aims to explore whether there are characteristic changes in the gut microbes of female MAD and whether these changes are associated with depressive-like behaviors. Meanwhile, this study observed alterations in the lipid metabolism function of gut microbes and further examined changes in plasma medium- and long-chain fatty acids (MLCFAs) in mice that underwent fecal microbiota transplantation (FMT).

METHODS

Stool samples obtained from 31 MAD, along with 24 healthy individuals (HC) were analyzed by 16 S rRNA gene sequencing. Meanwhile, 14-month-old female C57BL/6J mice received antibiotic cocktails and then oral gavage of the microbiota suspension of MAD or HC for 3 weeks to reconstruct gut microbiota. The subsequent depressive-like behaviors, the composition of gut microbiota, as well as MLCFAs in the plasma were evaluated.

RESULTS

A noteworthy disruption in gut microbial composition in MAD individuals compared to HC was observed. Several distinct bacterial taxa, including Dorea, Butyricicoccus, and Blautia, demonstrated associations with the demographic variables. A particular microbial panel encompassing 49 genera effectively differentiated MAD patients from HC (AUC = 0.82). Fecal microbiome transplantation from MAD subjects led to depressive-like behaviors and dysfunction of plasma MLCFAs in mice.

CONCLUSIONS

These findings suggest that microbial dysbiosis is linked to the pathogenesis of MAD, and its role may be associated with the regulation of MLCFAs metabolism.

Eicosapentaenoic Acid Modulates Transient Receptor Potential V1 Expression in Specific Brain Areas in a Mouse Fibromyalgia Pain Model

Pain is an unpleasant sensory and emotional experience accompanied by tissue injury. Often, an individual's experience can be influenced by different physiological, psychological, and social factors. Fibromyalgia, one of the most difficult-to-treat types of pain, is characterized by general muscle pain accompanied by obesity, fatigue, sleep, and memory and psychological concerns. Fibromyalgia increases nociceptive sensations via central sensitization in the brain and spinal cord level. We used intermittent cold stress to create a mouse fibromyalgia pain model via a von Frey test (day 0: 3.69 ± 0.14 g; day 5: 2.13 ± 0.12 g). Mechanical pain could be reversed by eicosapentaenoic acid (EPA) administration (day 0: 3.72 ± 0.14 g; day 5: 3.69 ± 0.13 g). A similar trend could also be observed for thermal hyperalgesia. The levels of elements in the transient receptor potential V1 (TRPV1) signaling pathway were increased in the ascending pain pathway, including the thalamus, medial prefrontal cortex, somatosensory cortex, anterior cingulate cortex, and cerebellum. EPA intake significantly attenuated this overexpression. A novel chemogenetics method was used to inhibit SSC and ACC activities, which presented an analgesic effect through the TRPV1 downstream pathway. The present results provide insights into the role of the TRPV1 signaling pathway for fibromyalgia and its potential as a clinical target.

The supplementation of a high dose of fish oil during pregnancy and lactation led to an elevation in Mfsd2a expression without any changes in docosahexaenoic acid levels in the retina of healthy 2-month-old mouse offspring

Introduction

During fetal development, the proper development of neural and visual systems relies on the maternal supplementation of omega-3 fatty acids through placental transfer. Pregnant women are strongly advised to augment their diet with additional sources of omega-3, such as fish oil (FO). This supplementation has been linked to a reduced risk of preterm birth, pre-eclampsia, and perinatal depression. Recently, higher doses of omega-3 supplementation have been recommended for pregnant women. Considering that omega-3 fatty acids, particularly docosahexaenoic acid (DHA), play a crucial role in maintaining the delicate homeostasis required for the proper functioning of the retina and photoreceptors the effects of high-dose fish oil (FO) supplementation during pregnancy and lactation on the retina and retinal pigmented epithelium (RPE) in healthy offspring warrant better understanding.

Methods

The fatty acid content and the changes in the expression of the genes regulating cholesterol homeostasis and DHA transport in the retina and RPE were evaluated following the high-dose FO supplementation.

Results

Our study demonstrated that despite the high-dose FO treatment during pregnancy and lactation, the rigorous DHA homeostasis in the retina and RPE of the two-month-old offspring remained balanced. Another significant finding of this study is the increase in the expression levels of major facilitator superfamily domain-containing protein (Mfsd2a), a primary DHA transporter. Mfsd2a also serves as a major regulator of transcytosis during development, and a reduction in Mfsd2a levels poses a major risk for the development of leaky blood vessels.

Conclusion

Impairment of the blood-retinal barrier (BRB) is associated with the development of numerous ocular diseases, and a better understanding of how to manipulate transcytosis in the BRB during development can enhance drug delivery through the BRB or contribute to the repair of central nervous system (CNS) barriers.

Mitochondrial might: powering the peripartum for risk and resilience

The peripartum period, characterized by dynamic hormonal shifts and physiological adaptations, has been recognized as a potentially vulnerable period for the development of mood disorders such as postpartum depression (PPD). Stress is a well-established risk factor for developing PPD and is known to modulate mitochondrial function. While primarily known for their role in energy production, mitochondria also influence processes such as stress regulation, steroid hormone synthesis, glucocorticoid response, GABA metabolism, and immune modulation - all of which are crucial for healthy pregnancy and relevant to PPD pathology. While mitochondrial function has been implicated in other psychiatric illnesses, its role in peripartum stress and mental health remains largely unexplored, especially in relation to the brain. In this review, we first provide an overview of mitochondrial involvement in processes implicated in peripartum mood disorders, underscoring their potential role in mediating pathology. We then discuss clinical and preclinical studies of mitochondria in the context of peripartum stress and mental health, emphasizing the need for better understanding of this relationship. Finally, we propose mitochondria as biological mediators of resilience to peripartum mood disorders.

Association of serum docosahexaenoic acid and eicosapentaenoic acid levels with dietary intakes and supplement use during pregnancy: a prospective observational study

This study aimed to determine the association of serum docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) levels with dietary intakes and supplement use during pregnancy. This prospective observational study was conducted at a university hospital in Tokyo, Japan. Participants in their second and third trimesters were given a self-administered questionnaire assessing the frequency of DHA and EPA supplement use in the past month and a brief-type self-administered diet history questionnaire. Non-fasting serum DHA and EPA levels were analysed using gas chromatography. Differences in biomarkers by frequency of supplement use were determined using multiple comparison analyses, and Spearman's correlation coefficient was used to determine biomarkers and DHA and EPA intakes by food group. Of the 116 participants, 11 (9⋅5 %) in the second trimester and 18 (15⋅5 %) in the third trimester regularly used supplements (≥5 times per week). Regular users had higher serum DHA and EPA levels than never users in the second and third trimesters. Dietary DHA and EPA intake from fish and shellfish was positively correlated with serum DHA and EPA in the second and third trimesters. Supplement use ≥5 times per week and fish and shellfish intake were associated with high serum DHA and EPA levels.

A network analysis of nutritional markers and maternal perinatal mental health in the French EDEN cohort

BACKGROUND

Perinatal maternal depression and anxiety are associated with adverse maternal outcomes, and nutrition may play an important role in their emergence. Previous research shows that certain micro and macronutrients found in different dietary patterns may associate with perinatal mood disorders. This study aims to explore relationships between nutrition during pregnancy and perinatal maternal depression and anxiety symptoms using network analyses.

METHODS

Using data from the French EDEN mother-child cohort, the sample consisted of 1438 women with available mental health outcomes (CES-D, STAI and EPDS) and nutritional markers collected from food frequency questionnaires. Four networks were constructed to explore the relationships between prenatal nutrient status, dietary patterns, and perinatal mental health, while accounting for important confounders.

RESULTS

The Healthy dietary pattern was associated with the presence of vital micronutrients, while the Western dietary pattern was consistently associated with poorer intake of specific micronutrients and contained an excess of certain macronutrients. Western dietary pattern and symptoms of postnatal depression were connected by a positive edge in both the macronutrient and micronutrient networks. Lower education levels were associated with higher Western dietary pattern scores, from which a positive edge linked to postnatal depression symptoms in both models.

CONCLUSIONS

A Western dietary pattern was associated with increased symptoms of postnatal depression in our adjusted network models; The Healthy dietary pattern was associated with essential micronutrients but not with symptoms of depression or anxiety. Perinatal mental health might be impacted by specific dietary patterns in the context of psychosocial and physical stress associated with pregnancy.

Modulatory effect of n-3 polyunsaturated fatty acids on depressive-like behaviors in rats with chronic sleep deprivation: potential involvement of melatonin receptor pathway and brain lipidome

Clinical evidence suggests that a bidirectional relationship is present between sleep loss and psychiatric disorders. Both melatonin receptor agonist ramelteon (RMT) and n-3 polyunsaturated fatty acids (n-3 PUFAs) exhibit antidepressant effects, while their underlying molecular mechanisms might be different. Thus, the present study aims to investigate the add-on effects and possible mechanisms of how RMT and different n-3 PUFAs modulate the melatonin receptor pathway as well as brain lipidome to ameliorate the neuropsychiatric behaviors displayed in rats under chronic sleep deprivation. Thirty-one 6-week-old male Wistar rats were divided into five groups: control (C), sleep deprivation (S), sleep deprivation treated with RMT (SR), sleep deprivation treated with RMT and eicosapentaenoic acid (C20:5n-3, EPA) (SRE), and sleep deprivation treated with RMT and docosahexaenoic acid (C22:6n-3, DHA) (SRD) groups. The results reveal that RMT plus EPA alleviated depressive-like behavior when the rats were subjected to the forced swimming test, whereas RMT plus DHA alleviated anxiety-like behavior when the rats were subjected to the elevated plus maze test. The results of a western blot analysis further revealed that compared with the rats in the S group, those in the SRE and SRD groups exhibited a significantly increased expression of MT₂ in the prefrontal cortex, with greater benefits observed in the SRE group. In addition, decreased BDNF and TrkB expression levels were upregulated only in the SRE group. Lipidomic analysis further revealed possible involvement of aberrant lipid metabolism and neuropsychiatric behaviors. RMT plus EPA demonstrated promise as having the effects of reversing the levels of the potential biomarkers of depressive-like behaviors. RMT plus EPA or DHA could ameliorate depressive- and anxiety-like behaviors in sleep-deprived rats through the alteration of the lipidome and MT₂ receptor pathway in the brain, whereas EPA and DHA exerted a differential effect.

Postpartum dietary intake, depression and the concentration of docosahexaenoic acid in mature breast milk in Wuhan, China

Background: Docosahexaenoic acid (DHA, C22:6) is an important fatty acid in breast milk and is essential for infantile growth and cognitive development. However, the factors that affect the DHA concentration in breast milk have not been completely clarified. Objective: This study aimed to characterize the composition of breast milk fatty acids and to identify maternal factors associated with breast milk DHA concentration in postpartum women in Wuhan, China. Methods: In this cross-sectional study, we analyzed milk fatty acids in 115 lactating women at 30-120 days postpartum using GC-MS. Maternal sociodemographic, health and other information were collected using a self-reported questionnaire. Maternal dietary intake information was collected through a 24-hour dietary recall method. Postpartum depression status was identified using the Edinburgh Postnatal Depression Scale (EPDS). Results: The mean DHA proportion in breast milk was 0.49%. The multivariate regression model showed that the milk DHA proportion was positively associated with maternal aquatic product intake (β = 0.183, 95%CI: 0.052, 0.314) and DHA supplement use (β = 0.146, 95%CI: 0.108, 0.185), and negatively associated with postpartum depression status (β = -0.122, 95%CI: -0.243, -0.002) after adjustment for several maternal and infant factors. Conclusion: Increasing maternal aquatic product intake and DHA supplement use and improving postpartum depression status may increase DHA concentration in breast milk in lactating women.

Higher n-3 polyunsaturated fatty acid status during early pregnancy is associated with lower risk for depression at 12 months postpartum: The NuPED study

Perinatal depression can negatively affect the health of the mother and her offspring. N-3 polyunsaturated fatty acids (PUFA) may play a role in the aetiology of depression. Therefore, we investigated the association of n-3 PUFA status during early pregnancy with perinatal depression among women living in urban Johannesburg, South Africa. For this prospective analysis, we analysed red blood cell (RBC) total phospholipid fatty acid (FA) composition (% of total FA) of 242 pregnant women at <18 weeks' gestation. We used the Edinburgh Postnatal Depression Scale (EPDS) to identify women at risk for depression (EPDS score ≥9) at <18, 22 and 36 weeks' gestation, and at 6 and 12 months postpartum. RBC EPA status was negatively (β=-0.22, p<0.05), and the AA/EPA ratio positively (β=0.24, p<0.05) associated with EPDS scores at 12 months postpartum. Higher RBC DHA and n-3 index were further associated with lower odds (OR=0.56 [95% CI: 0.32-0.91]; OR=0.63 [95% CI: 0.39-0.94]), while higher n-6/n-3 PUFA and AA/EPA ratios early in pregnancy were associated with higher odds for depression at 12 months postpartum ((OR=2.34 [95% CI: 1.12-4.97]; OR=1.02 [95% CI: 1.00-1.05]). Our results suggest that women with a higher RBC n-3 PUFA status during early pregnancy may be at lower risk for depression at 12 months postpartum.

A Preliminary Comparison of Plasma Tryptophan Metabolites and Medium- and Long-Chain Fatty Acids in Adult Patients with Major Depressive Disorder and Schizophrenia

Background and Objectives: Disturbance of tryptophan (Trp) and fatty acid (FA) metabolism plays a role in the pathogenesis of psychiatric disorders. However, quantitative analysis and comparison of plasma Trp metabolites and medium- and long-chain fatty acids (MCFAs and LCFAs) in adult patients with major depressive disorder (MDD) and schizophrenia (SCH) are limited. Materials and Methods: Clinical symptoms were assessed and the level of Trp metabolites and MCFAs and LCFAs for plasma samples from patients with MDD (n = 24) or SCH (n = 22) and healthy controls (HC, n = 23) were obtained and analyzed. Results: We observed changes in Trp metabolites and MCFAs and LCFAs with MDD and SCH and found that Trp and its metabolites, such as N-formyl-kynurenine (NKY), 5-hydroxyindole-3-acetic acid (5-HIAA), and indole, as well as omega-3 polyunsaturated fatty acids (N3) and the ratio of N3 to omega-6 polyunsaturated fatty acids (N3: N6), decreased in both MDD and SCH patients. Meanwhile, levels of saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) decreased in SCH patients, and there was a significant difference in the composition of MCFAs and LCFAs between MDD and SCH patients. Moreover, the top 10 differential molecules could distinguish the two groups of diseases from HC and each other with high reliability. Conclusions: This study provides a further understanding of dysfunctional Trp and FA metabolism in adult patients with SCH or MDD and might develop combinatorial classifiers to distinguish between these disorders.

Immune regulation of poly unsaturated fatty acids and free fatty acid receptor 4

Fatty acid metabolism contributes to energy supply and plays an important role in regulating immunity. Free fatty acids (FFAs) bind to free fatty acid receptors (FFARs) on the cell surface and mediate effects through the intra-cellular FFAR signaling pathways. FFAR4, also known as G-protein coupled receptor 120 (GPR120), has been identified as the primary receptor of omega-3 polyunsaturated fatty acids (ω-3 PUFAs). FFAR4 is a promising target for treating metabolic and inflammatory disorders due to its immune regulatory functions and the discovery of highly selective and efficient agonists. This review summarizes the reported immune regulatory functions of ω-3 PUFAs and FFAR4 in immune cells and immune-related diseases. We also speculate possible involvements of ω-3 PUFAs and FFAR4 in other types of inflammatory disorders.

Perinatal depression and serum vitamin D status: A cross-sectional study in urban China

BACKGROUND

Although vitamin D has been found to be associated with perinatal depression, the results are inconsistent. The aim of this cross-sectional study was to examine the association between vitamin D and PND in Chinese pregnant women and lactating women.

METHODS

A total of 1773 participants were included, including 907 lactating women and 866 pregnant women. The Edinburgh Postnatal Depression Scale (EPDS) was used to screen for PND, and those with scores ≥13 were considered to have PND. Serum 25-hydroxyvitamin D concentrations were assessed with high-performance liquid chromatography.

RESULTS

The prevalence of postpartum depression (PPD) and antenatal depression (AD) were 15.9 % and 9.8 %, respectively. Compared with individuals with sufficient vitamin D, those with vitamin D deficiency were associated with a higher prevalence of PPD in lactating women (OR = 1.71, 95%CI: 1.01-2.88, p = 0.044). The serum 25(OH)D of lactating women was inversely associated with the scores of the factor "depressive mood" of the EPDS (ORper 5 ng/mL = -0.10, 95%CI: -0.19 to -0.01, p = 0.032). No significant association between serum 25-hydroxyvitamin D and AD was observed.

LIMITATIONS

First, this study is a cross-sectional design, which can only determine associations but not causality. Secondly, this study only included participants from urban areas. Thirdly, there are still some possible confounding factors that have not been considered.

CONCLUSION

In conclusion, this study suggested a significant association between vitamin D status and PPD; however, the association between vitamin D status and AD was not significant.

Anti-Inflammatory Treatment Efficacy in Major Depressive Disorder: A Systematic Review of Meta-Analyses

Purpose

Immune imbalances in major depressive disorder (MDD) have been targeted by anti-inflammatory treatment approaches in clinical trials to increase responsiveness to therapy. However, even after several meta-analyses, no translation of evidence into clinical practice has taken place. We performed a systematic review to evaluate meta-analytic evidence of randomized controlled trials on the use of anti-inflammatory agents for MDD to summarize efficacy estimates and elucidate shortcomings.

Methods

Pooled effect estimates and heterogeneity indices were primary outcomes. Characteristics of the included meta-analyses were extracted. Scientific quality of meta-analyses was assessed using the Revised Assessment of Multiple Systematic Reviews (R-AMSTAR).

Results

N=20 meta-analyses met the eligibility criteria. Study characteristics like outcome scales, composition of patient populations, and add-on or monotherapy regimen varied very little for celecoxib studies, varied little for minocycline studies, and were rather variable for omega 3 fatty acids studies. R-AMSTAR scores ranged from 26 to 39 out of 44 points indicating variable quality, where a comprehensive literature search was the strongest and the consideration of scientific quality in the conclusions was the weakest domain across all meta-analyses. For minocycline and celecoxib, superiority was demonstrated with medium to large effect size with substantial heterogeneity and with large to very large effect size with negligible heterogeneity, respectively. For omega 3 fatty acids, superiority was also demonstrated with mainly small and medium effect sizes with substantial heterogeneity. However, for minocycline and omega 3 fatty acids, non-significant meta-analyses were found also.

Conclusion

Even in our synthesized approach, no clear recommendations could be derived on the use of anti-inflammatory treatment for MDD due to several critical aspects like heterogeneity, diversity of patient populations, treatment regimen, and outcomes, and limited scientific quality. However, we observed clear inter-substance differences with meta-analytic evidence being strongest for celecoxib and weakest for omega 3 fatty acids.

Possible antidepressant mechanisms of omega-3 polyunsaturated fatty acids acting on the central nervous system

Omega-3 polyunsaturated fatty acids (PUFAs) can play important roles in maintaining mental health and resistance to stress, and omega-3 PUFAs supplementation can display beneficial effects on both the prevention and treatment of depressive disorders. Although the underlying mechanisms are still unclear, accumulated evidence indicates that omega-3 PUFAs can exhibit pleiotropic effects on the neural structure and function. Thus, they play fundamental roles in brain activities involved in the mood regulation. Since depressive symptoms have been assumed to be of central origin, this review aims to summarize the recently published studies to identify the potential neurobiological mechanisms underlying the anti-depressant effects of omega-3 PUFAs. These include that of (1) anti-neuroinflammatory; (2) hypothalamus-pituitary-adrenal (HPA) axis; (3) anti-oxidative stress; (4) anti-neurodegeneration; (5) neuroplasticity and synaptic plasticity; and (6) modulation of neurotransmitter systems. Despite many lines of evidence have hinted that these mechanisms may co-exist and work in concert to produce anti-depressive effects, the potentially multiple sites of action of omega-3 PUFAs need to be fully established. We also discussed the limitations of current studies and suggest future directions for preclinical and translational research in this field.

Evidence based recommendations for an optimal prenatal supplement for women in the US: vitamins and related nutrients

The blood levels of most vitamins decrease during pregnancy if un-supplemented, including vitamins A, C, D, K, B1, B3, B5, B6, folate, biotin, and B12. Sub-optimal intake of vitamins from preconception through pregnancy increases the risk of many pregnancy complications and infant health problems. In the U.S., dietary intake of vitamins is often below recommended intakes, especially for vitamin D, choline and DHA. Many studies suggest that insufficient vitamin intake is associated with a wide range of pregnancy complications (anemia, Cesarean section, depression, gestational diabetes, hypertension, infertility, preeclampsia, and premature rupture of membranes) and infant health problems (asthma/wheeze, autism, low birth weight, congenital heart defects, intellectual development, intrauterine growth restriction, miscarriage, neural tube defects, orofacial defects, and preterm birth). The primary goal of this paper is to review the research literature and propose evidence-based recommendations for the optimal level of prenatal supplementation for each vitamin for most women in the United States. A secondary goal was to compare these new recommendations with the levels of vitamins in over 180 commercial prenatal supplements. The analysis found that prenatal supplements vary widely in content, often contained only a subset of essential vitamins, and the levels were often below our recommendations. This suggests that increasing prenatal vitamin supplementation to the levels recommended here may reduce the incidence of many pregnancy complications and infant health problems which currently occur.

Environmental risk factors, protective factors, and biomarkers for postpartum depressive symptoms: an umbrella review

We performed an umbrella review on environmental risk/protective factors and biomarkers for postpartum depressive symptoms to establish a hierarchy of evidence. We systematically searched PubMed, Embase, and the Cochrane Database of Systematic Reviews from inception until 12 January 2021. We included systematic reviews providing meta-analyses related to our research objectives. Methodological quality was assessed by AMSTAR 2, and the certainty of evidence was evaluated by GRADE. This review was registered in PROSPERO (CRD42021230784). We identified 30 articles, which included 45 environmental risk/protective factors (154,594 cases, 7,302,273 population) and 9 biomarkers (2018 cases, 16,757 population). The credibility of evidence was convincing (class I) for antenatal anxiety (OR 2.49, 1.91-3.25) and psychological violence (OR 1.93, 1.54-2.42); and highly suggestive (class II) for intimate partner violence experience (OR 2.86, 2.12-3.87), intimate partner violence during pregnancy (RR 2.81, 2.11-3.74), smoking during pregnancy (OR 2.39, 1.78-3.2), history of premenstrual syndrome (OR 2.2, 1.81-2.68), any type of violence experience (OR 2.04, 1.72-2.41), primiparity compared to multiparity (RR 1.76, 1.59-1.96), and unintended pregnancy (OR 1.53, 1.35-1.75).

Clinician guidelines for the treatment of psychiatric disorders with nutraceuticals and phytoceuticals: The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety Treatments (CANMAT) Taskforce

OBJECTIVES

The therapeutic use of nutrient-based 'nutraceuticals' and plant-based 'phytoceuticals' for the treatment of mental disorders is common; however, despite recent research progress, there have not been any updated global clinical guidelines since 2015. To address this, the World Federation of Societies of Biological Psychiatry (WFSBP) and the Canadian Network for Mood and Anxiety Disorders (CANMAT) convened an international taskforce involving 31 leading academics and clinicians from 15 countries, between 2019 and 2021. These guidelines are aimed at providing a definitive evidence-informed approach to assist clinicians in making decisions around the use of such agents for major psychiatric disorders. We also provide detail on safety and tolerability, and clinical advice regarding prescription (e.g. indications, dosage), in addition to consideration for use in specialised populations.

METHODS

The methodology was based on the WFSBP guidelines development process. Evidence was assessed based on the WFSBP grading of evidence (and was modified to focus on Grade A level evidence - meta-analysis or two or more RCTs - due to the breadth of data available across all nutraceuticals and phytoceuticals across major psychiatric disorders). The taskforce assessed both the 'level of evidence' (LoE) (i.e. meta-analyses or RCTs) and the assessment of the direction of the evidence, to determine whether the intervention was 'Recommended' (+++), 'Provisionally Recommended' (++), 'Weakly Recommended' (+), 'Not Currently Recommended' (+/-), or 'Not Recommended' (-) for a particular condition. Due to the number of clinical trials now available in the field, we firstly examined the data from our two meta-reviews of meta-analyses (nutraceuticals conducted in 2019, and phytoceuticals in 2020). We then performed a search of additional relevant RCTs and reported on both these data as the primary drivers supporting our clinical recommendations. Lower levels of evidence, including isolated RCTs, open label studies, case studies, preclinical research, and interventions with only traditional or anecdotal use, were not assessed.

RESULTS

Amongst nutraceuticals with Grade A evidence, positive directionality and varying levels of support (recommended, provisionally recommended, or weakly recommended) was found for adjunctive omega-3 fatty acids (+++), vitamin D (+), adjunctive probiotics (++), adjunctive zinc (++), methylfolate (+), and adjunctive s-adenosyl methionine (SAMe) (+) in the treatment of unipolar depression. Monotherapy omega-3 (+/-), folic acid (-), vitamin C (-), tryptophan (+/-), creatine (+/-), inositol (-), magnesium (-), and n-acetyl cysteine (NAC) (+/-) and SAMe (+/-) were not supported for this use. In bipolar disorder, omega-3 had weak support for bipolar depression (+), while NAC was not currently recommended (+/-). NAC was weakly recommended (+) in the treatment of OCD-related disorders; however, no other nutraceutical had sufficient evidence in any anxiety-related disorder. Vitamin D (+), NAC (++), methylfolate (++) were recommended to varying degrees in the treatment of the negative symptoms in schizophrenia, while omega-3 fatty acids were not, although evidence suggests a role for prevention of transition to psychosis in high-risk youth, with potential pre-existing fatty acid deficiency. Micronutrients (+) and vitamin D (+) were weakly supported in the treatment of ADHD, while omega-3 (+/-) and omega-9 fatty acids (-), acetyl L carnitine (-), and zinc (+/-) were not supported. Phytoceuticals with supporting Grade A evidence and positive directionality included St John's wort (+++), saffron (++), curcumin (++), and lavender (+) in the treatment of unipolar depression, while rhodiola use was not supported for use in mood disorders. Ashwagandha (++), galphimia (+), and lavender (++) were modestly supported in the treatment of anxiety disorders, while kava (-) and chamomile (+/-) were not recommended for generalised anxiety disorder. Ginkgo was weakly supported in the adjunctive treatment of negative symptoms of schizophrenia (+), but not supported in the treatment of ADHD (+/-). With respect to safety and tolerability, all interventions were deemed to have varying acceptable levels of safety and tolerability for low-risk over-the-counter use in most circumstances. Quality and standardisation of phytoceuticals was also raised by the taskforce as a key limiting issue for firmer confidence in these agents. Finally, the taskforce noted that such use of nutraceuticals or phytoceuticals be primarily recommended (where supportive evidence exists) adjunctively within a standard medical/health professional care model, especially in cases of more severe mental illness. Some meta-analyses reviewed contained data from heterogenous studies involving poor methodology. Isolated RCTs and other data such as open label or case series were not included, and it is recognised that an absence of data does not imply lack of efficacy.

CONCLUSIONS

Based on the current data and clinician input, a range of nutraceuticals and phytoceuticals were given either a supportive recommendation or a provisional recommendation across a range of various psychiatric disorders. However several had only a weak endorsement for potential use; for a few it was not possible to reach a clear recommendation direction, largely due to mixed study findings; while some other agents showed no obvious therapeutic benefit and were clearly not recommended for use. It is the intention of these guidelines to inform psychiatric/medical, and health professional practice globally.

Effect of High Ratio of n-6/n-3 PUFAs on Depression: A Meta-Analysis of Prospective Studies

Objective

The aim of this systematic review and meta-analysis was to examine the association between high ratio of n-6/n-3 polyunsaturated fatty acids (PUFAs) and depression.

Methods

The authors conducted a meta-analysis of research articles on the association of high ratio of n-6/n-3 PUFAs with the risk of depression published in the online article database on PubMed, Embase, Cochrane library as of December 2021. Pooled odds ratios (OR) were calculated using random effects models. Publication bias was assessed visually by funnel plots and statistically by the Egger’s and Begg’s tests.

Results

Finally, 12 studies included in this systematic review and meta-analysis with a total of 66,317 participants (including 4,173 individuals with depression condition). The pooled results showed that high ratio of n-6/n-3 PUFAs might be positively associated with depression [OR = 1.21, 95% confidence intervals (CIs): 1.04∼1.41]. The I² test indicated that there was a substantial statistical heterogeneity across the included studies (I² = 54.38%, P = 0.01). Subgroup analysis showed that high ratio of n-6/n-3 PUFAs in blood had no significant association with depression (OR = 1.15, 95%CI: 0.88∼1.50), while high ratio of n-6/n-3 PUFAs in dietary supplements was positively associated with depression (OR = 1.32, 95%CI: 1.16∼1.51).

Conclusion

This meta-analysis confirmed the association between high ratio of n-6/n-3 PUFAs and the risk of depression. High ratio of n-6/n-3 PUFAs in dietary supplementation was positively associated with depression, but had no significant association in the blood. This study suggested that lowering the dietary intake of the ratio of n-6/n-3 PUFAs would be beneficial in the prevention of depression.

Gestational diabetes mellitus decreased umbilical cord blood polyunsaturated fatty acids: a meta-analysis of observational studies

BACKGROUND

Polyunsaturated fatty acid (PUFA) is important for the development of the fetal brain, and the retina. Gestational diabetes mellitus (GDM) may influence maternal and fetal fatty acid metabolism, in turn affecting fetal growth and development. In several studies, maternal and fetal PUFA metabolic differences have been reported between mothers with and without GDM, but not in other studies. Thus, the aim of this meta-analysis (registration number: CRD42020220448) was to compare levels of linoleic acid (LA), α-linolenic acid (ALA), arachidonic acid (AA), docosahexaenoic acid (DHA), and total n-3 and n-6 PUFA between mothers with and without GMD and their fetuses.

METHODS

We performed a meta-analysis of observational studies on maternal and fetal fatty acid metabolism, published until May 2021. In addition, we performed subgroup analysis depending on the analyzed tissues (plasma/serum, erythrocyte membrane, or placenta) and the expression modes of fatty acids (concentration or percentage).

RESULTS

We included 24 observational studies involving 4335 maternal datasets and 12 studies involving 1675 fetal datasets in the meta-analysis. Levels of AA, DHA, and n-6 and n-3 PUFA were lower in the cord blood of mothers with GDM than in controls (P  <  0.05). Compared to that in controls, in erythrocyte membranes, the percentages of AA, DHA, and n-6 and n-3 PUFA in total fatty acid were lower in mothers with GDM (P  <  0.05), but in plasma/serum, the percentages of AA, DHA, and n-6 PUFA in total fatty acid were higher in mothers with GDM (P  <  0.05).

CONCLUSIONS

GDM appears to influence the transfer of PUFAs from mothers to fetuses. The percentage of PUFAs in maternal plasma/serum was higher, and that in erythrocyte membranes was lower in mothers with GDM compared to those with normal glucose tolerance.

Exploring the therapeutic potential of omega-3 fatty acids in depression

Omega-3 fatty acids have been acknowledged for their number of holdings on an individual's health. Not only in physical valuation but also in managing psychiatric disorders, omega-3 fatty acids have been found to be a powerful formula. It is proclaimed that depressive patients suffer anomaly with the levels of omega-3 polyunsaturated fatty acids in the body, coupled with insignificant EPA and DHA. Enhancement in brain functioning, neuronal functions, and paying attention in interacting with the brain cells are some of the additional tasks, being performed by the supplementation of omega-3 fatty acids. The leading and primary source via dietary supplementation involves the involvement of fish and fish products. These are hypothesized to be the best and dominant source for omega-3 fatty acids. Consumption of omega-3 fatty acid is well safe, that physician highly favors intake of these supplements, remarkably in the case of pregnant women. However, treating this serious life-threatening mental disorder leads to many adverse effects when treated with antidepressants. The dose range includes 1g/d to 10g/d, which is to be incorporated by the patient. It is also tested that the combination of EPA and DHA is found to be more efficacious for a person in treating and preventing depressive symptoms. Some studies verify the supplementation of omega-3 fatty acids in diet was coequally productive and successful with minimal side effects when analyzed with antidepressants. Despite these facts, much research is still needed and presently in process for long-term safety and studying the role of omega-3 fatty acids in human health.

Controversies involving the use of SSRIs during pregnancy and the increased risk of having a child with autism spectrum disorders – a case report and literature review

Introduction: There is an ongoing debate as to whether the use of selective serotonin reuptake inhibitors (SSRIs) by pregnant women increases the risk of developing autism spectrum disorders (ASD) in the offspring.

Aim: The aim of the study was to

1) present, based on a case report, the potential factors that may affect the development of ASD in a child,

2) review the literature on the risk of ASD in the case of using SSRIs by a pregnant woman.

Case report: The case report concerns a child of a 33-year-old patient, previously treated for an episode of depression at the age of 23. At the beginning of the 15th week of planned pregnancy, when she was 28 years old, sleep disturbances were observed. Over the next few weeks, she gradually developed a full-blown depressive syndrome which required the use of sertraline. The child was born through a natural delivery, a healthy boy, who was diagnosed with ASD at the age of 2.5 years, which was the trigger for the development of the third episode of depression in the patient.

Conclusions: The results of the research indicate that SSRIs can penetrate the placental barrier, influencing the processes of serotoninergic transmission in the fetus, disrupting neurodevelopmental processes. On the other hand, a higher risk of ASD development in children of depressed mothers who do not use pharmacotherapy was confirmed, compared to the general population and in the case of the occurrence of depressive episodes in mother in the past and in relation to the male fetuses. The greater risk of ASD in children of mothers who take SSRIs may not only be associated with the medication itself but also with the presence of depression and the probable common genetic basis for both disorders. In each case, other risk factors for the development of ASD should also be taken into consideration, e.g. vitamin D3 deficiencies, unsaturated fatty acids, oxytocin levels, the presence of intestinal dysbiosis.

The efficacy of probiotics and/or n-3 long-chain polyunsaturated fatty acids intervention on maternal prenatal and postnatal depressive and anxiety symptoms among overweight and obese women

BACKGROUND

Maternal depression and anxiety may endanger well-being of both mother and child. We investigated the efficacy of probiotics and/or fish oil (FO) in modifying pre- and postnatal depressive and anxiety symptoms. Symptom trajectories were identified and the influence of lifestyle factors on symptoms was evaluated.

METHODS

Overweight women (n = 439) were randomized to intervention groups (probiotics+FO, probiotics+placebo, FO+placebo, placebo+placebo) from early pregnancy until six months postpartum, and assessed for depressive and anxiety symptoms with Edinburgh Postnatal Depression Scale (EPDS) and Anxiety subscale of Symptoms Checklist (SCL-90) at early and late pregnancy and three, six and 12 months postpartum. Latent growth mixture modeling was used to model the symptom courses. Dietary quality and physical activity were assessed with validated indices.

RESULTS

Symptom scores were generally low. Statistically significant intervention effect was seen during pregnancy (p = 0.017): EPDS scores increased (by 1.11 points) in the FO+probiotics group and decreased (by 0.85 points) in the FO+placebo group. At 12 months postpartum, FO+placebo group had lower EPDS scores compared to probiotics+placebo group (p = 0.039). No differences in SCL scores were seen in response to the intervention. Irrespective of the intervention, three depressive and two anxiety symptoms trajectories were identified. Dietary quality correlated negatively with depressive symptoms in early pregnancy and six months postpartum and with anxiety symptoms in early pregnancy. Perinatal events including mother-reported colic were related to symptoms.

LIMITATIONS

Secondary outcomes of the primary trial.

CONCLUSIONS

Intervention had a modest impact on depressive symptoms. Diet and obstetric events were associated with depressive and anxiety symptoms.

Omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation for prevention and treatment of perinatal depression: a systematic review and meta-analysis of randomized-controlled trials

BACKGROUND

Available interventions for preventing and treating perinatal depression remain unsatisfactory.

AIMS

We examined the prophylactic and therapeutic effects, as well as adverse effects, of n-3 PUFA supplementation in reducing depressive symptoms during perinatal periods.

METHODS

We included randomized, placebo-controlled trials that reported the changes of depression severity after the perinatal participants received n-3 PUFA supplementation. After the comprehensive searches in October 2019, we selected the trials, extracted the data, and assessed the quality of included trials. We compared the standardized mean differences (SMD) of depression score changes between groups using a random-effect model.

RESULTS

We included 11 trials in the meta-analysis and one more trial for qualitative analysis (N = 3,181). The pooled standardized mean of decreased depression scores revealed no statistically significant difference between the n-3 PUFA and the placebo groups (N = 920, SMDs = -0.05, 95% CI -0.20 to 0.10, I² = 21%). The pooled SMDs showed no statistically significant efficacy of n-3 PUFA supplementation for prevention (N = 779, SMDs = -0.03, 95% CI -0.20 to 0.13, I² = 24%) and treatment (N = 141, SMDs = -0.14, 95% CI -0.55 to 0.27, I² = 31%) of perinatal depression. The efficacy of n-3 PUFA supplementation was not associated with the daily doses of DHA, EPA, or DHA plus EPA. No trial reported any serious adverse effect of n-3 PUFA supplements.

CONCLUSIONS

Although n-3 PUFA supplementation may improve maternal and infant outcomes, our meta-analysis found insufficient evidence to determine its benefit for perinatal depression.

Importance of EPA and DHA Blood Levels in Brain Structure and Function

Brain structure and function depend on a constant and sufficient supply with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) by blood. Blood levels of EPA and DHA reflect dietary intake and other variables and are preferably assessed as percentage in erythrocytes with a well-documented and standardized analytical method (HS-Omega-3 Index^®). Every human being has an Omega-3 Index between 2 and 20%, with an optimum of 8–11%. Compared to an optimal Omega-3 Index, a lower Omega-3 Index was associated with increased risk for total mortality and ischemic stroke, reduced brain volume, impaired cognition, accelerated progression to dementia, psychiatric diseases, compromises of complex brain functions, and other brain issues in epidemiologic studies. Most intervention trials, and their meta-analyses considered EPA and DHA as drugs with good bioavailability, a design tending to produce meaningful results in populations characterized by low baseline blood levels (e.g., in major depression), but otherwise responsible for many neutral results and substantial confusion. When trial results were evaluated using blood levels of EPA and DHA measured, effects were larger than comparing EPA and DHA to placebo groups, and paralleled epidemiologic findings. This indicates future trial design, and suggests a targeted use EPA and DHA, based on the Omega-3 Index.

Brain Responses to Emotional Stimuli after Eicosapentaenoic Acid and Docosahexaenoic Acid Treatments in Major Depressive Disorder: Toward Personalized Medicine with Anti-Inflammatory Nutraceuticals

N-3 polyunsaturated fatty acid supplements improve the symptoms of major depressive disorder (MDD) in randomized-controlled trials and meta-analyses, with the higher efficacy from anti-inflammatory eicosapentaenoic acid (EPA) than brain-dominant docosahexaenoic acid (DHA). To investigate the specific brain mechanisms of the anti-inflammatory anti-depressant nutraceutical compounds, we recruited 24 MDD subjects in this double-blind, head-to-head study with a 12-week EPA or DHA treatment (clinical trial registration number: NCT03871088). The depression severity was assessed by Hamilton depression rating scale (HAM-D). Brain responses to emotional stimuli were measured by a 3-Tesla MRI. The correlation between HAM-D scores and brain responses also were tested. Compared to 18 healthy controls, the brain responses of untreated 24 MDD patients mainly revealed hypoactivity in the regions associated with emotion perception and emotion control when processing positive emotion. After treatment, more remitted MDD patients have been observed in the EPA as compared to the DHA groups. In addition, the EPA, but not DHA, treatment revealed increased activity in the regions associated with emotion perception and cognitive control when processing positive emotion. The correlation analysis further revealed negative correlation between HAM-D scores and brain responses in cognitive control regions. The results of this study may imply the compensatory brain responses of cognitive and emotion controls by EPA but not DHA and underpin personalized medicine with anti-inflammatory nutraceuticals toward depression treatments.

Low Omega-3 intake is associated with high rates of depression and preterm birth on the country level

Low circulating levels of long chain omega-3 polyunsaturated fatty acids (LC omega-3 PUFA) have been linked to major depressive disorder (MDD) and preterm birth (PTB), and prenatal depression associates with PTB. We therefore hypothesized that low Omega-3 intake would associate with higher MDD and PTB rates on the country-level. To test this hypothesis, we obtained country-level estimates for omega-3 intake, MDD prevalence, PTB rate, and per capita income for 184 countries in 2010. We then estimated the LC omega-3 PUFA levels that these intakes produce by accounting for direct consumption and the endogenous conversion of ingested plant-based precursors. Penalized splines indicated that MDD and PTB rates decreased linearly with increasing LC omega-3 PUFA, up to ~ 1000 mg/day for MDD and up to ~ 550 mg/day for PTB. Adjusted linear regression models below these thresholds revealed that a one standard deviation increase in LC omega-3 PUFA (380 mg/day) was associated with an MDD decrease of 5 cases/1000 people and a PTB decrease of 15 cases/1000 livebirths. In light of the extensive prior evidence on the individual-level, these findings indicate that low intake of LC omega-3 PUFA and its precursors may be elevating MDD and PTB rates in 85% of the countries studied.

Acute EPA-induced learning and memory impairment in mice is prevented by DHA

Eicosapentaenoic acid (EPA), an omega-3 fatty acid, has been widely used to prevent cardiovascular disease (CVD) and treat brain diseases alone or in combination with docosahexaenoic acid (DHA). However, the impact of EPA and DHA supplementation on normal cognitive function and the molecular targets of EPA and DHA are still unknown. We show that acute administration of EPA impairs learning and memory and hippocampal LTP in adult and prepubescent mice. Similar deficits are duplicated by endogenously elevating EPA in the hippocampus in the transgenic fat-1 mouse. Furthermore, the damaging effects of EPA are mediated through enhancing GABAergic transmission via the 5-HT₆R. Interestingly, DHA can prevent EPA-induced impairments at a ratio of EPA to DHA similar to that in marine fish oil via the 5-HT_2CR. We conclude that EPA exhibits an unexpected detrimental impact on cognitive functions, suggesting that caution must be exercised in omega-3 fatty acid supplementation and the combination of EPA and DHA at a natural ratio is critical for learning and memory and synaptic plasticity.

Acute administration of EPA impairs learning and memory and hippocampal LTP in mice that was mediated through enhancing GABAergic transmission via the 5-HT₆R. DHA can prevent EPA-induced impairments at a ratio of EPA to DHA similar to that in marine fish oil via the 5-HT_2CR.

Dietary intake of fish and n-3 polyunsaturated fatty acids and risk of postpartum depression: a nationwide longitudinal study - the Japan Environment and Children's Study (JECS)

BACKGROUND

Pregnant women require increased levels of n-3 polyunsaturated fatty acids (PUFAs) due to the demands of the growing fetus. Although some evidence indicates that maternal intake of fish and n-3 PUFAs is associated with reduced risk of postpartum depression, the results are inconsistent.

METHODS

We investigated whether dietary consumption of fish and/or n-3 PUFAs during pregnancy is associated with a reduced risk of maternal postpartum depression at 6 months after delivery and of serious mental illness at 1 year in a Japanese population. After exclusion and multiple imputation from a dataset comprising 103 062 pregnancies obtained in the Japan Environment and Children's Study, we evaluated 84 181 and 81 924 women at 6 months and 1 year after delivery, respectively.

RESULTS

Multivariable logistic regression showed a reduced risk of postpartum depression at 6 months in the second to fifth quintiles v. the lowest quintile for fish and n-3 PUFA intake, with trend tests also revealing a significant linear association. At 1 year after delivery, fish intake was associated with a reduced risk of serious mental illness in the second to fifth quintiles v. the lowest quintile for fish and in the third to fifth quintiles v. the lowest quintile for n-3 PUFA intake, with trend tests also revealing a significant linear association.

CONCLUSIONS

Women with higher fish and/or n-3 PUFA intake showed reduced risk of postpartum depression at 6 months after delivery and of serious mental illness at 1 year after delivery.

Prenatal risk factors for internalizing and externalizing problems in childhood

BACKGROUND

A growing body of research has documented the effects of prenatal risk factors on a wide spectrum of adverse offspring health outcomes. Childhood behavior problems, such as externalizing and internalizing problems, are no exception. This comprehensive literature review aims to summarize and synthesize current research about commonly experienced prenatal risk factors associated with internalizing and externalizing problems, with a focus on their impact during childhood and adolescence. Potential mechanisms as well as implications are also outlined.

DATA SOURCES

The EBSCO, Web of Science, PubMed, Google Scholar, and Scopus databases were searched for studies examining the association between prenatal risk factors and offspring internalizing/externalizing problems, using keywords "prenatal" or "perinatal" or "birth complications" in combination with "internalizing" or "externalizing". Relevant articles, including experimental research, systematic reviews, meta-analyses, cross-sectional and longitudinal cohort studies, and theoretical literature, were reviewed and synthesized to form the basis of this integrative review.

RESULTS

Prenatal risk factors that have been widely investigated with regards to offspring internalizing and externalizing problems encompass health-related risk factors, including maternal overweight/obesity, substance use/abuse, environmental toxicant exposure, maternal infection/inflammation, as well as psychosocial risk factors, including intimate partner violence, and anxiety/depression. Collectively, both epidemiological and experimental studies support the adverse associations between these prenatal factors and increased risk of emotional/behavioral problem development during childhood and beyond. Potential mechanisms of action underlying these associations include hormonal and immune system alterations. Implications include prenatal education, screening, and intervention strategies.

CONCLUSIONS

Prenatal risk factors are associated with a constellation of offspring internalizing and externalizing problems. Identifying these risk factors and understanding potential mechanisms will help to develop effective, evidence-based prevention, and intervention strategies.

Human Gut-Microbiota Interaction in Neurodegenerative Disorders and Current Engineered Tools for Its Modeling

The steady increase in life-expectancy of world population, coupled to many genetic and environmental factors (for instance, pre- and post-natal exposures to environmental neurotoxins), predispose to the onset of neurodegenerative diseases, whose prevalence is expected to increase dramatically in the next years. Recent studies have proposed links between the gut microbiota and neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. Human body is a complex structure where bacterial and human cells are almost equal in numbers, and most microbes are metabolically active in the gut, where they potentially influence other target organs, including the brain. The role of gut microbiota in the development and pathophysiology of the human brain is an area of growing interest for the scientific community. Several microbial-derived neurochemicals involved in the gut-microbiota-brain crosstalk seem implicated in the biological and physiological basis of neurodevelopment and neurodegeneration. Evidence supporting these connections has come from model systems, but there are still unsolved issues due to several limitations of available research tools. New technologies are recently born to help understanding the causative role of gut microbes in neurodegeneration. This review aims to make an overview of recent advances in the study of the microbiota-gut-brain axis in the field of neurodegenerative disorders by: (a) identifying specific microbial pathological signaling pathways; (b) characterizing new, advanced engineered tools to study the interactions between human cells and gut bacteria.

The efficacy and safety of omega-3 fatty acids on depressive symptoms in perinatal women: a meta-analysis of randomized placebo-controlled trials

Omega-3 fatty acids (FA), as a nutrient, has been proven effective in major depressive disorder (MDD), however, the results of monotherapy in perinatal depression (PND) remain unclear. To examine the efficacy and safety of omega-3 fatty acids (FA) monotherapy for perinatal depression (PND) compared with placebo. PubMed, Embase, PsycINFO, MEDLINE, Cochrane Library, and CINAHL were searched from inception up to November 2019. The reference lists of relevant review articles and included studies were also reviewed. Randomized placebo-controlled trials examining the efficacy and safety of omega-3 FA monotherapy in perinatal women with depressive symptoms were included. Pooled standard mean differences (SMD) were calculated and random-effects models were adopted for all analyses. Subgroups analyses and meta-regression were performed to quantify characteristics of the subjects and trials influencing the omega-3 response. In addition, meta-regression was conducted to identify the source of heterogeneity. The study protocol was registered at PROSPERO, CRD42020159542. Eight eligible randomized placebo-controlled trials were included involving 638 participants. There was a significant effect of omega-3 FA on perinatal depression. Omega-3 with higher ratio of EPA/DHA (≥1.5) had significant efficacy both in mild-to-moderate pregnant and postpartum depression with low incidence of side effects. Among the included trials reporting adverse effects, there was no significant difference in incidence of gastrointestinal and neurologic events between the omega-3 and placebo groups. There was no evidence of publication bias. Our findings suggested that omega-3 FA significantly improved depressive symptoms in perinatal women regardless of pregnant or postpartum and well-tolerated. Furthermore, the omega-3 response was linked to higher EPA proportion in omega-3 formula and mild- to-moderate depression.

Polybrominated diphenyl ether (PBDE) and poly- and perfluoroalkyl substance (PFAS) exposures during pregnancy and maternal depression

BACKGROUND

Experimental studies in rodents suggest that polybrominated diphenyl ethers (PBDEs) and poly- and perfluoroalkyl substances (PFAS) may contribute to depressive symptoms. Few studies have examined the impact of these chemicals on depression in adults.

OBJECTIVE

To examine the associations between serum PBDE and PFAS concentrations during pregnancy and repeated measures of depressive symptoms in women assessed from pregnancy to 8 years postpartum.

METHODS

This study was based on 377 women from the Health Outcomes and Measures of the Environment Study, a birth cohort in Cincinnati, OH (USA). PBDEs (BDE-28, -47, -99, -100, -153, and ∑PBDEs) and PFAS (perfluorooctanoate [PFOA], perfluorooctane sulfonate [PFOS], perfluorohexane sulfonate [PFHxS], perfluorononanoate [PFNA]) were quantified in maternal serum at 16 ± 3 weeks gestation. Depressive symptoms were measured using the Beck Depression Inventory-II (BDI-II) at ~20 weeks gestation and up to seven times during postpartum visits (4 weeks, 1, 2, 3, 4, 5, and 8 years). We used linear mixed models to estimate covariate-adjusted associations between chemical concentrations and repeated measures of BDI-II. Multinomial logistic regression models were used to estimate the relative risk ratios of having a medium or high depression trajectory.

RESULTS

We found that a 10-fold increase in BDE-28 at 16 ± 3 weeks gestation was associated with significantly increased BDI-II scores (β = 2.5 points, 95% confidence interval [CI] 0.8, 4.2) from pregnancy to 8 years postpartum. Significant positive associations were also observed with BDE-47, -100, -153, and ∑PBDEs. A 10-fold increase in ∑PBDEs was associated with a 4.6-fold increased risk (95% CI 1.8, 11.8) of a high trajectory for BDI-II compared to a low trajectory. We observed no significant associations between PFAS and BDI-II scores.

CONCLUSION

PBDEs during pregnancy were associated with more depressive symptoms among women in this cohort.

Persistently High Levels of Maternal Antenatal Inflammation Are Associated With and Mediate the Effect of Prenatal Environmental Adversities on Neurodevelopmental Delay in the Offspring

BACKGROUND

Prenatal exposure to environmental adversities, including maternal overweight/obesity, diabetes/hypertensive disorders, or mood/anxiety disorders, increases the risk for adverse neurodevelopmental outcomes in children. However, the underlying biological mechanisms remain elusive. We tested whether maternal antenatal inflammation was associated with the number of neurodevelopmental delay areas in children and whether it mediated the association between exposure to any prenatal environmental adversity and child neurodevelopmental delay.

METHODS

Mother-child dyads (N = 418) from the PREDO (Prediction and Prevention of Preeclampsia and Intrauterine Growth Restriction) study were followed up to 10.8 years. We analyzed maternal plasma high-sensitivity C-reactive protein and glycoprotein acetyls at 3 consecutive antenatal time points, measured maternal body mass index in early pregnancy, extracted data on diabetes/hypertensive disorders in pregnancy from medical records, and extracted data on mood/anxiety disorders until childbirth from the Care Register for Health Care. To estimate the number of neurodevelopmental delay areas in children across cognitive, motor, and social functioning, we pooled data from the Care Register for Health Care on psychological development disorders with mother-reported Ages and Stages Questionnaire data on developmental milestones.

RESULTS

Higher levels of maternal high-sensitivity C-reactive protein and glycoprotein acetyls at and across all 3 antenatal time points were associated with 1.30- to 2.36-fold (p values < .02) increased relative risk for higher number of areas of child neurodevelopmental delay. Higher maternal inflammation across the 3 time points also mediated the effect of any prenatal environmental adversity on child neurodevelopmental delay.

CONCLUSIONS

Higher levels of maternal inflammation, especially when persisting throughout pregnancy, increase a child's risk of neurodevelopmental delay and mediate the effect of prenatal environmental adversity on child neurodevelopmental delay.

PPAR and functional foods: Rationale for natural neurosteroid-based interventions for postpartum depression

Allopregnanolone, a GABAergic neurosteroid and progesterone derivative, was recently approved by the Food and Drug Administration for the treatment of postpartum depression (PPD). Several mechanisms appear to be involved in the pathogenesis of PPD, including neuroendocrine dysfunction, neuroinflammation, neurotransmitter alterations, genetic and epigenetic modifications. Recent evidence highlights the higher risk for incidence of PPD in mothers exposed to unhealthy diets that negatively impact the microbiome composition and increase inflammation, all effects that are strongly correlated with mood disorders. Conversely, healthy diets have consistently been reported to decrease the risk of peripartum depression and to protect the body and brain against low-grade systemic chronic inflammation. Several bioactive micronutrients found in the so-called functional foods have been shown to play a relevant role in preventing neuroinflammation and depression, such as vitamins, minerals, omega-3 fatty acids and flavonoids. An intriguing molecular substrate linking functional foods with improvement of mood disorders may be represented by the peroxisome-proliferator activated receptor (PPAR) pathway, which can regulate allopregnanolone biosynthesis and brain-derived neurotropic factor (BDNF) and thereby may reduce inflammation and elevate mood. Herein, we discuss the potential connection between functional foods and PPAR and their role in preventing neuroinflammation and symptoms of PPD through neurosteroid regulation. We suggest that healthy diets by targeting the PPAR-neurosteroid axis and thereby decreasing inflammation may offer a suitable functional strategy to prevent and safely alleviate mood symptoms during the perinatal period.

Clinical Efficacy and Biological Regulations of ω-3 PUFA-Derived Endocannabinoids in Major Depressive Disorder

BACKGROUND

Endocannabinoids (ECs) are one type of bioactive endogenous neuroinflammatory mediator derived from polyunsaturated fatty acids (PUFAs), which may regulate the emotional processes. Here, we assessed the effect of ω-3 PUFAs on EC levels, which may be the novel targets for the ω-3 PUFAs' antidepressive effects.

METHODS

We conducted a 12-week double-blind, nonplacebo, randomized controlled trial. Eighty-eight major depressive disorder (MDD) participants were randomly assigned to receive eicosapentaenoic acid (EPA, 3.0 g/day), docosahexaenoic acid (DHA, 1.4 g/day), or a combination of EPA (1.5 g/d) and DHA (0.7 g/day). Eighty-five participants completed the trial, and their clinical remission and plasma PUFA-derived EC levels (pmol/mL) were measured.

RESULTS

The cumulative rates of clinical remission were significantly higher in the EPA and EPA + DHA groups than the DHA group (51.85 and 53.84 vs. 34.37%; p =0.027 and p =0.024, respectively). EPA and EPA + DHA treatments increased the eicosapentaenoylethanolamide (EPEA) levels compared to DHA treatment (0.33 ± 0.18 and 0.35 ± 0.24 vs. 0.08 ± 0.12; p =0.002 and p =0.001, respectively), while EPA + DHA treatment increased the docosahexaenoylethanolamide levels more than EPA treatment (1.34 ± 2.09 vs. 0.01 ± 1.79; p =0.006). Plasma EPEA levels were positively correlated with rates of clinical remission (hazard ratio: 1.60, 95% confidence interval: 1.08-2.39).

CONCLUSIONS

Treatments enriched with EPA increased plasma EPEA levels, which was positively associated with clinical remission. This finding may suggest that levels of plasma EPEA play a potential novel endogenous therapeutic target in MDD.

Omega-3 Fatty Acids in Pregnancy-The Case for a Target Omega-3 Index

Scientific societies recommend increasing intake of docosahexaenoic acid (DHA) by 200 mg/day during pregnancy. However, individually, clinical events correlate quite strongly with levels of eicosapentaenoic acid (EPA) and DHA in blood, but these levels poorly correlate with amounts ingested. EPA and DHA in erythrocytes (Omega-3 Index) have a low biologic variability. If analyzed with a standardized analytical procedure (HS-Omega-3 Index^®), analytical variability is low. Thus, the largest database of any fatty acid analytical method was provided. Pregnant women in Germany had a mean Omega-3 Index below the target range suggested for cardiovascular disease of 8–11%, with large interindividual variation, and quite independent of supplementation with EPA and DHA. In Germany, premature birth is a major health issue. Premature birth and other health issues of pregnant women and their offspring correlate with levels of EPA and DHA in blood and can be reduced by increasing intake of EPA and DHA, according to individual trials and pertinent meta-analyses. Very high intake or levels of EPA and DHA may also produce health issues, like bleeding, prolonged gestation, or even premature birth. While direct evidence remains to be generated, evidence from various scientific approaches supports that the target range for the Omega-3 Index of 8–11% might also pertain to pregnancy and lactation.

Impact of erythrocyte long-chain omega-3 polyunsaturated fatty acid levels in early pregnancy on birth outcomes: findings from a Belgian cohort study

OBJECTIVE

To examine the association between maternal erythrocyte long-chain omega-3 PUFA (n-3 LCPUFA), measured in early pregnancy, and pregnancy and birth outcomes.

STUDY DESIGN

One hundred and eight healthy women with a singleton pregnancy were included. Erythrocyte fatty acids were analyzed using gas chromatography. Gestational length, birth anthropometric measures, and pregnancy-associated complications were collected from hospital medical records.

RESULTS

We observed significant positive associations between maternal docosahexaenoic acid (DHA) levels (p = 0.024) and omega-3 index values (p = 0.021) and gestational length in adjusted linear regression models. Each point in maternal DHA level was associated with 2.19 days longer gestational duration (β = 2.19; 95% CI 0.29-4.09). No consistent associations were found between n-3 PUFA levels and composite pregnancy outcome.

CONCLUSION

These findings suggest that the gestational length is positively affected by maternal n-3 LCPUFA status as soon as the early stages of pregnancy.

Association of dietary n-3 polyunsaturated fatty acids intake with depressive symptoms in midlife women

BACKGROUND

To study the association of n-3 polyunsaturated fatty acid (n-3 PUFA) intake from diet with depressive symptoms in midlife women.

METHODS

Data for this cross-sectional study were retrieved from baseline assessment of the Study of Women's Health Across the Nation (SWAN). Logistic regression and restricted cubic spline models were performed to examine the association n-3 PUFA intake with depressive symptoms.

RESULTS

A total of 3054 women aged 42-52 years were included in the present study. In overall midlife women, n-3 PUFA intake was not significantly associated with depressive symptoms (CES-D score ≥16) after adjustment for potential confounders. In early perimenopausal women, n-3 PUFA intake was inversely associated with depressive symptoms after adjustment for potential confounders. The fully adjusted OR with 95% CI of depressive symptoms were 0.062 (0.009-0.457) in the highest quartile (n-3 PUFAs intake was categorized by quartiles) compared with the lowest quartile for n-3 PUFA intake. Restricted cubic spline analyses showed that n-3 PUFA intake were dose-response inversely associated with depressive symptoms in early perimenopausal women. However, in premenopausal women, no significant association between depressive symptoms and n-3 PUFA intake was observed.

LIMITATIONS

This was a cross-sectional study, limiting causal inferences.

CONCLUSION

Dietary n-3 PUFA may be inversely associated with depressive symptoms in early perimenopausal women, but not in premenopausal women.

Metabolomic evidence for the therapeutic effect of gentiopicroside in a corticosterone-induced model of depression

BACKGROUND

Depression is a disease that seriously threatens the quality of human life. To explore the effect of gentiopicroside on depression, this study investigated the therapeutic effect of gentiopicroside on corticosterone-induced depressionin vivo and in vitro by using metabolomic methods.

METHODS

A total of 36 rats were randomly assigned to three groups: a normal group, model group (depression), and treatment group (depression + gentiopicroside). Corticosterone was administrated to induce depression-like model rats. Morris water maze test was used to validated the behavior performance. The hippocampus of rats was obtained for metabolomic detection. Metabolites that were differentially expressed between the groups were extracted for Heatmap, Go, and pathway enrichment analyses. Finally, neuronal cells were cultured and examined to validated the effect of gentiopicroside.

RESULTS

Corticosterone injured rats learning capacity, and decreased the levels of 5-HT, and reversed by gentiopicroside delivery. Metabolites obtained from the hippocampus of rats in the three groups were subjected to a principal component analysis (PCA). Go and pathway enrichment analyses revealed the involvement of sphingolipid metabolism et al. Gentiopicroside could inhibit apoptosis caused by corticosterone, and also decrease neuronal cell proliferation and BDNF levels in vitro. Arachidonic acid (ARA) reversed the protective effect of gentiopicroside on neuronal cells.

CONCLUSION

These findings suggest that gentiopicroside reduces apoptosis and increases the proliferation of hippocampus cells in depressed animals by regulating metabolites. Moreover, our study provides a new basis for the clinical treatment of depression and demonstrates the potential efficacy of gentiopicroside in this area of pathology.

Perinatal dietary omega-3 fatty acid deficiency reduces maternal nurturing behavior in rats: dissociation from elevated pro-inflammatory signaling

Objectives: Maternal-pup nurturing behavior has previously been shown to impact offspring neurodevelopment independent of diet. Here we investigated the effects of perinatal maternal n-3 fatty acid deficiency on maternal-pup nurturing behavior and potential associations with pro-inflammatory signaling.Methods: Eight-week-old virgin female Long-Evans hooded rats were randomized to a control diet containing alpha-linolenic acid (ALA, 18:3n-3) (CON, n = 10) or an ALA-free diet (Deficient, DEF, n = 11) 30 d prior to mating. On postnatal day 2 (P2) litters were culled to eight per dam. On P3, P6, and P9 dams and their litters were video recorded and maternal nurturing behaviors, including licking/grooming of pups and arched-back nursing, were scored by a blinded rater. Following weaning on P21, dam postmortem central (prefrontal cortex, PFC) and peripheral (red blood cell, RBC) fatty acid composition and central (PFC IL-1β, IL-2, IL-6, TNFα, cPLA₂, COX-2 mRNA) and peripheral (plasma IL-1β, IL-2, IL-6, TNFα, CRP) pro-inflammatory biostatus assessed.Results: DEF dams exhibited significantly lower RBC (p ≤ 0.0001) and PFC (p ≤ 0.0001) docosahexaenoic acid (DHA) levels compared with CON dams. Irrespective of diet dams exhibited significantly lower RBC, but not PFC, DHA levels compared with non-parous rats. DEF dams exhibited less licking/grooming (p = 0.008), arched-back nursing (p ≤ 0.0001) and blanket nursing (p = 0.003), and exhibited more passive nursing (p = 0.003) but not time off pups (p = 0.1), compared with CON dams. PFC and plasma inflammatory measures did not differ significantly between groups.Discussion: Perinatal dietary n-3 fatty acid deficiency reduces maternal nurturing behavior and this effect is not associated with enduring elevations in pro-inflammatory signaling.

Trim the fat: the role of omega-3 fatty acids in psychopharmacology

The American Psychiatric Association (APA) currently recommends the use of omega-3 fatty acid supplementation for depressive disorders, impulse-control disorders, and psychotic disorders in treatment guidelines. This review examines the evidence for efficacy of omega-3 fatty acids in depressive disorders, bipolar disorder, anxiety disorders, post-traumatic stress disorder (PTSD), and psychosis. Meta-analysis of randomized-controlled trials of omega-3 fatty acids for depression are inconclusive, with strong evidence of publication bias, sizable heterogeneity between included studies, and substantial methodological shortcomings in included trials. The large amount of heterogeneity in findings of RCTs of omega-3 fatty acids for unipolar depression is likely attributable to highly heterogeneous sample populations that are given different omega-3 supplements [which differ widely in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) content, ratio, and dosage] as either adjunctive or monotherapy of other existing treatments, and then measure several different outcomes of depression symptomatology with likely incomplete blinding. Evidence of efficacy of omega-3 supplementation in treating psychosis, PTSD, anxiety, and bipolar mania is minimal. The current guidelines recommending the use of omega-3 fatty acids in adulthood psychiatric conditions should be revisited, especially given several recent negative studies examining the effects of omega-3 fatty acids for cardiovascular disease. Recommending likely ineffective treatment to patients, no matter how benign the side-effect profile, has opportunity cost (e.g. other more effective medications or therapies not being utilized) and likely affects patient compliance with other evidence-based treatments.

Imbalance between Omega-6 and Omega-3 Polyunsaturated Fatty Acids in Early Pregnancy Is Predictive of Postpartum Depression in a Belgian Cohort

While studies revealed that the omega-3 polyunsaturated fatty acids (n-3 PUFA) and their mediators would be able to regulate several biological processes involved into the development of postpartum depression (PPD), evidence from observational studies remains mixed. The aim of the present study was to investigate the association between maternal erythrocyte n-3 PUFA, measured in early pregnancy, and the risk of PPD. A Belgian cohort of 72 healthy women was screened. Erythrocyte fatty acids were analysed using gas chromatography. PPD was assessed using the Bromley Postnatal Depression Scale by phone interview one year after delivery. We observed a significant negative association between docosahexaenoic acid (DHA) levels and the risk of postpartum depression in the adjusted model (p = 0.034). Higher n-6/n-3 and arachidonic acid (AA)/eicosapentaenoic acid (EPA) ratios were significantly associated with an increased odds of PPD (p = 0.013 and p = 0.043, respectively). Women with an omega-3 index <5% had a 5-fold increased risk of depressive episode than did those with an omega-3 index ≥5% (OR 5.22 (95% CI 1.24–21.88)). A low n-3 PUFA status, alone and combined with high n-6 PUFA status, in early pregnancy was associated with a greater risk of PPD. Management of maternal n-3 PUFA deficiency can be a simple, safe and cost-effective strategy for the prevention of this major public health issue.

Importance of n-3 PUFA consumption during pregnancy: perception discrepancies between pregnant women and gynaecologists-obstetricians in Belgium

OBJECTIVE

n-3 PUFA during pregnancy have been subject to intense research interest, but also much controversy, creating a situation of confusion among patients and health-care providers. The present study was carried out to explore knowledge, attitude and practices regarding n-3 PUFA in two independent populations of pregnant women and gynaecologists-obstetricians in Belgium and to assess the relationship between the pregnant women's attributes and their n-3 PUFA status measured by the omega-3 index.

DESIGN

Cross-sectional study. Knowledge, attitude and practices were collected by self-administered questionnaires while laboratory data were available for each pregnant woman.

SETTING

During the first antenatal hospital appointment (for the pregnant women) and by email (for the gynaecologists-obstetricians).ParticipantsWomen in early pregnancy (n 122) and gynaecologists-obstetricians (n 67).

RESULTS

Marked discrepancies in perception were evidenced between the pregnant women and health-care providers. While 82 % of the women attached high importance to n-3 PUFA during pregnancy, only a third of the gynaecologists-obstetricians did. About 35 % of the women declared paying particular attention to their consumption of n-3 PUFA. After adjusting for sociodemographic characteristics, these positive dietary practices were significantly associated with higher omega-3 index (P=0·04). Overall, 43·3 % of professionals did not provide any information about n-3 PUFA to their pregnant patients and 46·3 % did not take any preventive actions.

CONCLUSIONS

Evidence-based guidelines, refreshment training and communication tools are needed to improve awareness and clinical practices among caregivers regarding n-3 PUFA to benefit both mothers and their children.

Role of Soluble Epoxide Hydrolase in Metabolism of PUFAs in Psychiatric and Neurological Disorders

Inflammation plays a key role in the pathogenesis of a number of psychiatric and neurological disorders. Soluble epoxide hydrolases (sEH), enzymes present in all living organisms, metabolize epoxy fatty acids (EpFAs) to corresponding 1,2-diols by the addition of a molecule of water. Accumulating evidence suggests that sEH in the metabolism of polyunsaturated fatty acids (PUFAs) plays a key role in inflammation. Preclinical studies demonstrated that protein expression of sEH in the prefrontal cortex, striatum, and hippocampus from mice with depression-like phenotype was higher than control mice. Furthermore, protein expression of sEH in the parietal cortex from patients with major depressive disorder was higher than controls. Interestingly, Ephx2 knock-out (KO) mice exhibit stress resilience after chronic social defeat stress. Furthermore, the sEH inhibitors have antidepressant effects in animal models of depression. In addition, pharmacological inhibition or gene KO of sEH protected against dopaminergic neurotoxicity in the striatum after repeated administration of MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) in an animal model of Parkinson’s disease (PD). Protein expression of sEH in the striatum from MPTP-treated mice was higher than control mice. A number of studies using postmortem brain samples showed that the deposition of protein aggregates of α-synuclein, termed Lewy bodies, is evident in multiple brain regions of patients from PD and dementia with Lewy bodies (DLB). Moreover, the expression of the sEH protein in the striatum from patients with DLB was significantly higher compared with controls. Interestingly, there was a positive correlation between sEH expression and the ratio of phosphorylated α-synuclein to α-synuclein in the striatum. In the review, the author discusses the role of sEH in the metabolism of PUFAs in inflammation-related psychiatric and neurological disorders.

Complementary Health Practices for Treating Perinatal Depression

This article provides a focused review of the evidence for several complementary health approaches (ie, omega-3 fatty acids, folate, vitamin D, selenium, zinc, magnesium, B vitamins, physical activity, yoga) in the treatment of perinatal depression. There is evidence that some of these treatments may be reasonable to consider in women during pregnancy or the postpartum period. However, there are little data on the comparative safety and efficacy of these relative to traditional treatments (eg, psychotherapy, pharmacotherapy). Adequately powered high-quality studies are necessary to determine the role of complementary health practices for treating perinatal depression.

Essential Role of Keap1-Nrf2 Signaling in Mood Disorders: Overview and Future Perspective

Depression is one of the most common mood disorders with a high rate of relapse. Accumulating evidence suggests that the transcription factor Kelch-like erythroid cell-derived protein with CNC homology (ECH)-associated protein 1 (Keap1)-Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) system plays a key role in inflammation which is involved in depression. Preclinical studies demonstrated that the protein expressions of Keap1 and Nrf2 in the prefrontal cortex (PFC), CA3 and dentate gyrus (DG) of hippocampus in mice with depression-like phenotype were lower than control mice. In the learned helplessness paradigm, the protein levels of Keap1 and Nrf2 in the PFC and DG of hippocampus from rats with depression-like phenotype were also lower than control and resilient rats. Furthermore, rodents with depression-like phenotype have higher levels of pro-inflammatory cytokines. Interestingly, Nrf2 knock-out (KO) mice exhibit depression-like phenotype, and higher serum levels of pro-inflammatory cytokines compared with wild-type mice. Furthermore, Nrf2 KO mice have lower expression of brain-derived neurotrophic factor (BDNF) in the PFC, and CA3 and DG of hippocampus compared to wild-type mice. 7,8-Dihydroxyflavone, a TrkB agonist, showed antidepressant effects in Nrf2 KO mice, by stimulating BDNF-TrkB in the PFC, CA3, and DG. Pretreatment with sulforaphane, a naturally occurring Nrf2 activator, prevented depression-like phenotype in mice after inflammation, or chronic social defeat stress. Interestingly, dietary intake of 0.1% glucoraphanin (a precursor of sulforaphane) containing food during juvenile and adolescent stages of mice could prevent depression-like phenotype in adulthood after chronic social defeat stress. Moreover, the protein expressions of Keap1 and Nrf2 in the parietal cortex from major depressive disorder and bipolar disorder were lower than controls. These findings suggest that Keap1-Nrf2 system plays a key role in the stress resilience which is involved in the pathophysiology of mood disorders. It is, therefore, possible that dietary intake of cruciferous vegetables including glucoraphanin (or SFN) may prevent or minimize relapse from remission, induced by stress and/or inflammation in depressed patients. In the review, the author would like to discuss the role of Keap1-Nrf2 system in mood disorders.