Prenatal immunologic predictors of postpartum depressive symptoms: a prospective study for potential diagnostic markers

Inflammatory biomarkers and perinatal depression: A systematic review

BACKGROUND

Approximately 10 to 20% of pregnant women worldwide experience perinatal depression (PND), a depressive episode with onset during pregnancy or after childbirth. We performed a systematic review to identify, summarize and discuss studies on inflammatory biomarkers described in relation to PND.

METHOD

Inclusion criteria defined the selection of observational studies written in English, French, Spanish or Portuguese, that evaluate analytical levels of inflammatory molecules (protein levels) in biological fluids in women, with a diagnosis of depression using ICD/DSM diagnostic criteria or depressive symptoms assessed by standardized psychometric instruments, during pregnancy and/or postpartum. Case reports, experimental studies, reviews, qualitative analysis, meta-analysis, gray literature or replicated data were excluded. Three electronic databases were used for search (Pubmed, Web of Science and PsychInfo) and quality assessment of selected studies were performed using the Newcastle-Ottawa Scale. Data extraction included study design; number of subjects; obstetric information; tools and timepoints of depression and inflammatory markers assessment.

RESULTS

56 studies (sample size for cross-sectional and case-control studies ranging from 10 to 469; sample size for longitudinal studies ranging from 26 to 467), where the major aim was to analyze the association between depression and inflammatory biomarkers during pregnancy and postpartum period were included in this systematic review. Overall, the findings of our systematic review lend support to the hypothesis that several inflammatory markers may be associated with peripartum depressive symptoms. The associations were somewhat different looking at pregnancy compared to the delivery time-point and postpartum, and mainly referred to increased levels of IL-6, IL-8, CRP and TNF-α among depressed.

DISCUSSION

In summary, our systematic review findings provide evidence supporting the hypothesis that several inflammatory markers may correlate with peripartum depressive symptoms. However, our work also highlighted notable differences in the timing of biological sampling for inflammatory markers and in the methodologies used to assess depression during the perinatal period. Additionally, variations were observed in how inflammatory biomarkers and depression were approached, including their classification as exposure or outcome variables, and the timing of assessments. It is essential for future research to investigate the influence of biological fluids and the timing of assessments for both inflammatory biomarkers and depression to gain a deeper understanding of their association. This comprehensive exploration is pivotal for elucidating the intricate relationship between inflammation and perinatal depression.

Efficacy and safety of celecoxib for treatment of mild to moderate postpartum depression: a randomized, double-blind, placebo-controlled trial

PURPOSE

Evidence has demonstrated the roles of inflammatory processes in pathogenesis of depression. We aim to assess the effects of adjunctive celecoxib with cognitive behavioral therapy (CBT), an anti-inflammatory agent, in treatment of postpartum depression and on levels of Brain-derived neurotrophic factor (BDNF) and inflammatory cytokines.

METHODS

This was a randomized, double-blind, placebo-controlled trial to investigate the effects of adjunctive celecoxib with CBT on postpartum depression. Fifty outpatient women with postpartum depression, participated in this study. Patients randomly received either a celecoxib capsule twice a day or a placebo capsule twice a day for 6 weeks. Patients were assessed using the Hamilton Depression Rating Scale (HDRS) and the adverse event checklist at baseline and weeks 2, 4, and 6.

RESULTS

Patients in the celecoxib group showed a greater decline in HDRS scores from baseline to all three study time points compared to the placebo group (p = 0.12 for week 2, p = 0.001 for week 4, p < 0.001 for week 6). Rate of response to treatment was significantly higher in the celecoxib group compared to the placebo group at week 4 (60 vs 24%, p = 0.010) and week 6 (96 vs 44%, p < 0.001). Rate of remission was significantly higher in the celecoxib group compared to the placebo group at week 4 (52 vs 20%, p = 0.018) and week 6 (96 vs 36%, p < 0.001). Levels of most inflammatory markers were significantly lower in the celecoxib group compared to the placebo group at week 6. Levels of BDNF were significantly higher in the celecoxib group compared to the placebo group at week 6 (p < 0.001).

CONCLUSIONS

Findings suggest adjunctive celecoxib is an effective treatment for the improvement of postpartum depressive symptoms.

Regulatory T-cell phenotypes in prenatal psychological distress

BACKGROUND

Experiencing symptoms of psychological distress during pregnancy is common and has been linked to dysregulated immune functioning. In this context, immunoregulatory function is especially relevant because of its crucial role in establishment and maintenance of healthy pregnancy. However, little research has examined associations between women's prenatal psychological distress and immunoregulatory biomarkers. We investigated how symptoms of depression, anxiety, and stress relate to circulating levels of regulatory T-cells (Tregs).

MATERIALS AND METHODS

Pregnant Latina women were assessed at around 12 weeks of pregnancy (N = 82). These assessments included blood draws and self-report questionnaires assessing symptoms of depression, state anxiety, pregnancy-related anxiety, and perceived stress. Flow cytometry on PBMCs was used to quantify circulating Tregs, defined as CD3+CD4+CD25hiCD127loFoxP3+, and subpopulations positive for one of the following intra- or extracellular markers, CD45RA, CTLA-4, Helios, PD-1, TIM-3, and TIGIT. We collected 82 samples at 12 weeks. Multivariable linear regressions tested for associations between symptoms of psychological distress and Treg concentrations, adjusted for gestational age.

RESULTS

State anxiety symptoms at 12 weeks were negatively associated with parent Treg cell levels (b = -4.02, p = 0.023) and subpopulations Helios+ (b = -3.29, p = 0.019) and TIM3+ (b = -3.17, p = 0.008). Perceived stress was negatively associated with the PD-1+ subpopulation at 12 weeks (b = -4.02, p = 0.023). Depression was not related to Tregs or the subpopulations.

CONCLUSION

Our observation that symptoms of anxiety and stress are related to tolerogenic immunology suggests a possible biomechanism explaining correlations of maternal mood disorders with adverse outcomes for mothers and offspring.

Treg cell: Critical role of regulatory T-cells in depression

Depression is a highly prevalent disorder of the central nervous system. The neuropsychiatric symptoms of clinical depression are persistent and include fatigue, anorexia, weight loss, altered sleep patterns, hyperalgesia, melancholia, anxiety, and impaired social behaviours. Mounting evidences suggest that neuroinflammation triggers dysregulated cellular immunity and increases susceptibility to psychiatric diseases. Neuroimmune responses have transformed the clinical approach to depression because of their roles in its pathophysiology and their therapeutic potential. In particular, activated regulatory T (Treg) cells play an increasingly evident role in the inflammatory immune response. In this review, we summarized the available data and discussed in depth the fundamental roles of Tregs in the pathogenesis of depression, as well as the clinical therapeutic potential of Tregs. We aimed to provide recent information regarding the potential of Tregs as immune-modulating biologics for the treatment and prevention of long-term neuropsychiatric symptoms of depression.

Inflammatory pathophysiological mechanisms implicated in postpartum depression

Postpartum Depression (PPD) is a serious psychiatric disorder of women within the first year after delivery. It grievously damages women's physical and mental health. Inflammatory reaction theory is well-established in depression, and also has been reported associated with PPD. This review summarized the inflammatory pathophysiological mechanisms implicated in PPD, including decreased T cell activation, increased proinflammatory cytokines secretion, active kynurenine pathway, and initiated NLRP3 inflammasome. Clinical and preclinical research are both gathered. Potential therapeutical alternatives targeting the inflammatory mechanisms of PPD were introduced. In addition, this review briefly discussed the differences of inflammatory mechanisms between PPD and depression. The research of inflammation in PPD is limited and seems just embarking, which indicates the direction we can further study. As a variety of risky factors contribute to PPD collectively, therapy for women with PPD should be comprehensive, and clinical heterogeneity should be taken into consideration. As PPD has a predictability, early clinical screening and interventions are also needed. This review aims to help readers better understand the inflammatory pathological mechanisms in PPD, so as to identify biomarkers and potential therapeutic targets in the future.

Longitudinal assessment of inflammatory markers in the peripartum period by depressive symptom trajectory groups

Objective

Mechanisms driving temporal fluctuations of inflammatory markers during pregnancy, and how these might differ between distinct perinatal depressive trajectories, are not well understood. The aim of this study was to investigate cytokines levels over the course of pregnancy in women with different trajectories of depressive symptoms peripartum, and relate the levels to levels of non-pregnant controls.

Methods

Based on the Edinburgh Postnatal Depression Scale and/or selective serotonin reuptake inhibitors use, 131 women were categorized into: no (n = 65); antepartum (APD, n = 19), postpartum (PPD, n = 17) and persistent (n = 30) depressive symptoms. Plasma samples (n = 386) were analyzed for levels of interleukin (IL)-8, IL-18, Tumor necrosis factor-α, macrophage colony-stimulating factor (M-CSF), vascular endothelial growth factor A (VEGF-A) and fractalkine, at four different time-points (twice during pregnancy, during childbirth, and postpartum) using Bio-Plex Pro Human Cytokine Assays. Generalized linear mixed models were applied to analyze the associations between cytokine levels, time-point, perinatal depressive symptom trajectory group and their interaction.

Results

For all markers but VEGF-A, pregnancy was associated with higher cytokine levels compared to the non-pregnant controls, with delivery being the most prominent time-point. For M-CSF, IL-18 and VEGF-A, levels were back to the non-pregnant status at postpartum week 8. An effect of perinatal depressive symptom trajectory groups on cytokine levels was found for VEGF-A. Women with PPD and women with APD had lower levels of VEGF-A throughout the study period compared to women with persistent depression, and women with PPD had lower levels compared to non-depressed women.

Conclusions

Lower levels of VEGF-A were noted among women in some trajectories of depressive symptoms peripartum. The peripartum period is a time of tremendous immune system adaptations. Standardization of time-points for cytokine measurements in studies of perinatal depression are important in order to draw valid conclusions on the role of the immune system in perinatal depression.

Inflammatory and neurodegenerative pathophysiology implicated in postpartum depression

Postpartum depression (PPD) is the most common psychiatric complication associated with pregnancy and childbirth with debilitating symptoms that negatively impact the quality of life of the mother as well as inflict potentially long-lasting developmental impairments to the child. Much of the theoretical pathophysiology put forth to explain the emergence of PPD overlaps with that of major depressive disorder (MDD) and, although not conventionally described in such terms, can be seen as neurodegenerative in nature. Framing the disorder from the perspective of the well-established inflammatory theory of depression, symptoms are thought to be driven by dysregulation, and subsequent hyperactivation of the body's immune response to stress. Compounded by physiological stressors such as drastic fluctuations in hormone signaling, physical and psychosocial stressors placed upon new mothers lay bare a number of significant vulnerabilities, or points of potential failure, in systems critical for maintaining healthy brain function. The inability to compensate or properly adapt to meet the changing demands placed upon these systems has the potential to damage neurons, hinder neuronal growth and repair, and disrupt neuronal circuit integrity such that essential functional outputs like mood and cognition are altered. The impact of this deterioration in brain function, which includes depressive symptoms, extends to the child who relies on the mother for critical life-sustaining care as well as important cognitive stimulation, accentuating the need for further research.

The role of inflammation in the pathogenesis of perinatal depression and offspring outcomes

The role of inflammation in the pathogenesis of depression is becoming increasingly apparent, but its role in perinatal depression is less well-studied. Pregnancy and the postpartum are characterised by distinct and changing inflammatory profiles throughout, which makes the study of depression-related alterations in this period complex. This review presents literature discussing a role for the immune system in both antenatal and postnatal depression. Furthermore, literature investigating the role of the maternal immune system on breast milk composition and offspring immunological and behavioural outcomes is discussed, before concluding with suggestions for future work as this developing field grows.

Metabolite trajectories across the perinatal period and mental health: A preliminary study of tryptophan-related metabolites, bile acids and microbial composition

Depression and anxiety during pregnancy and postpartum are common, but affected women differ in timing, trajectories, and extent of symptoms. The objective of this pilot, feasibility study is to analyze trajectories of serotonin and tryptophan-related metabolites, bile acid metabolites, and microbial composition, in relation to psychiatric history and current symptoms across the perinatal period. Serum and fecal samples were collected from 30 women at three times points in the perinatal period and assayed with LC-MS/MS and 16S sequencing respectively. We defined mean trajectories for each metabolite, clustered individuals by metabolite trajectories, tested associations between metabolites, and examined metabolite levels in relation to microbial composition. Findings of note include: (1) changes in kynurenine and the ratio of kynurenic acid to kynurenine from second trimester to third trimester were strongly associated with baseline primary and secondary bile acids. (2) Secondary bile acid UDCA and its conjugated forms were associated with lower bacterial diversity and levels of Lachnospiraceae, a taxa known to produce Short Chain Fatty Acids. (3) History of anxiety was associated with UDCA levels, but history of major depression was not associated with any of the bile acids. (4) There was a trend towards lower dietary fiber for those with history of anxiety or depression. Overall, our results reveal substantial temporal variation in tryptophan-related metabolites and in bile acid metabolites over the perinatal period, with marked inter-individual variability. Trajectories of TRP -related metabolites, primary and secondary bile acids, and the absence or presence of microbes that produce Short Chain Fatty Acids (SCFAs) considered in concert have the potential to differentiate individuals based on perinatal adaptations that may impact mental and overall health.

A new molecular risk pathway for postpartum mood disorders: clues from steroid sulfatase-deficient individuals

Postpartum mood disorders develop shortly after childbirth in a significant proportion of women. These conditions are associated with a range of symptoms including abnormally high or low mood, irritability, cognitive disorganisation, disrupted sleep, hallucinations/delusions, and occasionally suicidal or infanticidal ideation; if not treated promptly, they can substantially impact upon the mother's health, mother-infant bonding, and family dynamics. The biological precipitants of such disorders remain unclear, although large changes in maternal immune and hormonal physiology following childbirth are likely to play a role. Pharmacological therapies for postpartum mood disorders can be effective, but may be associated with side effects, concerns relating to breastfeeding, and teratogenicity risks when used prophylactically. Furthermore, most of the drugs that are used to treat postpartum mood disorders are the same ones that are used to treat mood episodes during non-postpartum periods. A better understanding of the biological factors predisposing to postpartum mood disorders would allow for rational drug development, and the identification of predictive biomarkers to ensure that 'at risk' mothers receive earlier and more effective clinical management. We describe new findings relating to the role of the enzyme steroid sulfatase in maternal postpartum behavioural processes, and discuss how these point to a novel molecular risk pathway underlying postpartum mood disorders. Specifically, we suggest that aberrant steroid hormone-dependent regulation of neuronal calcium influx via extracellular matrix proteins and membrane receptors involved in responding to the cell's microenvironment might be important. Testing of this hypothesis might identify novel therapeutic targets and predictive biomarkers.

Postpartum Depression: Current Status and Possible Identification Using Biomarkers

Postpartum depression (PPD) is a serious health issue that can affect about 15% of the female population within after giving birth. It often conveys significant negative consequences to the offsprings. The symptoms and risk factors are somewhat similar to those found in non-postpartum depression. The main difference resides in the fact that PPD is triggered by postpartum specific factors, including especially biological changes in the hormone levels. Patients are usually diagnosed using a questionnaire onsite or in a clinic. Treatment of PPD often involves psychotherapy and antidepressant medications. In recent years, there have been more researches on the identification of biological markers for PPD. In this review, we will focus on the current research status of PPD, with an emphasis on the recent progress made on the identification of PPD biomarkers.

Pregnancy associated epigenetic markers of inflammation predict depression and anxiety symptoms in response to discrimination

Latina mothers, who have one of the highest fertility rates among ethnic groups in the United States (US), often experience discrimination. Psychosocial influences during pregnancy, such as discrimination stress, promotes inflammation. However, the role of epigenetic markers of inflammation as a mediator between, and predictor of, maternal discrimination stress and neuropsychiatric outcomes has not been extensively studied. The current study investigates the role of DNA methylation at FOXP3 Treg-cell-specific demethylated region (TSDR), as a marker of regulatory T (Treg) cells that are important negative regulators of inflammation, and the promoter of tumour necrosis factor-alpha (TNF-α) gene, an important pro-inflammatory cytokine, in relation to discrimination stress during pregnancy and depression and anxiety symptomatology.

A sample of 148 Latina women residing in the US (mean age 27.6 years) were assessed prenatally at 24–32 weeks’ gestation and 4–6 weeks postnatally for perceived discrimination exposure (Everyday Discrimination Scale, EDS), emotional distress (depression, anxiety, perinatal-specific depression), acculturation, and acculturative stress. DNA methylation levels at the FOXP3 and TNFα promoter regions from blood samples collected at the prenatal stage were assessed by bisulphite pyrosequencing.

Regression analyses showed that prenatal EDS associated with postnatal emotional distress, depression and anxiety symptoms only in those individuals with higher than mean levels of FOXP3 TSDR and TNFα promoter methylation; no such significant associations were found in those with lower than mean levels of methylation for either. We further found that these relationships were mediated by TNFα only in those with high FOXP3 TSDR methylation, implying that immunosuppression via TNFα promoter methylation buffers the impact of discrimination stress on postpartum symptomatology. These results indicate that epigenetic markers of immunosuppression and inflammation play an important role in resilience or sensitivity, respectively, to prenatal stress.

Biomarker screening for antenatal depression in women who underwent caesarean section: a matched observational study with plasma Lipidomics

BACKGROUND

Antenatal depression is a prevalent mental disorder in women who have undergone caesarean section, and it often presages adverse postoperative outcomes. Because of the lack of a laboratory-based diagnostic strategy, antenatal depression is mainly determined by a psychologist's subjective judgment based on a structured clinical interview for established diagnostic criteria. However, the diagnostic accuracy rate for depression by non-psychiatrists is relatively low. Thus, this study aimed to use lipidomics to identify potential biomarkers related to antenatal depression in women who have undergone caesarean section.

METHODS

The study was designed as a matched prospective observational study. Singleton pregnant women scheduled to receive elective caesarean section, were screened for eligibility. Women diagnosed with major antenatal depression were matched with non-antenatal depression controls in terms of age (±1 year) and BMI (±1 kg/m²), and blood samples of the included matched pairs were collected. Subsequently, lipidomics of the plasma samples were performed using Ultra Performance Liquid Chromatography-mass spectrometry analysis to explore the differentially expressed lipids in women with or without antenatal depression.

RESULTS

In total, 484 pregnant women were screened; 66 subjects were recruited, including 33 subjects with major antenatal depression and 33 matched controls without antenatal depression. Thirty-five differentially expressed lipid metabolites were identified (P < 0.05). The area under the receiver operating characteristic curve of these lipid metabolites was 0.7 or larger; the area under curve for cholesterol sulfate was 0.823 (95% CI: 0.716-0.930), and that of PC (18:2 (2E, 4E)/0:0) was 0.778 (95%CI: 0.662-0.895). In the conditional logistic stepwise regression analysis, cholesterol sulfate (P = 0.009) and PC (18:2 (2E, 4E)/0:0) (P = 0.035) were also identified as effective predictive risk factors for antenatal depression.

CONCLUSIONS

Women who had undergone caesarean section and experienced antenatal depression presented a significantly differentially expressed profile of plasma lipidomics compared to those who did not experience antenatal depression. Cholesterol sulfate and PC (18:2 (2E, 4E)/0:0) may be effective and specific lipidic biomarkers for the prediction of antenatal depression.

TRIAL REGISTRATION

China Clinical Trial Registration Center registration number: ChiCTR1800016230 ; date of registration: 21/05/2018.

Intergenerational transmission of depression: clinical observations and molecular mechanisms

Maternal mental illness can have a devastating effect during the perinatal period, and has a profound impact on the care that the baby receives and on the relationships that the baby forms. This review summarises clinical evidence showing the effects of perinatal depression on offspring physical and behavioural development, and on the transmission of psychopathology between generations. We then evaluate a number of factors which influence this relationship, such as genetic factors, the use of psychotropic medications during pregnancy, the timing within the perinatal period, the sex of the foetus, and exposure to maltreatment in childhood. Finally, we examine recent findings regarding the molecular mechanisms underpinning these clinical observations, and identify relevant epigenetic and biomarker changes in the glucocorticoid, oxytocin, oestrogen and immune systems, as key biological mediators of these clinical findings. By understanding these molecular mechanisms in more detail, we will be able to improve outcomes for both mothers and their offspring for generations.

[Inflammatory Biomarkers and Postpartum Depression: A Systematic Review of Literature]

OBJECTIVE

Postpartum Depression (PPD) affects over 15% new mothers. Its etiology is multifactorial and still partly unknown. Some hypotheses suggest a link with inflammation. This review aims to explore the existence of inflammatory biomarkers associated with PPD. The possibility of potential adjunct treatments, linked with these biomarkers, will be discussed.

METHOD

The systematic review of literature was performed using in PubMed, PsycInfo and Embase, and 25 articles were included. Various biomarkers were identified. The most often studied are C-reactive protein (CRP), interleukins 6 and 10, tumor necrosis factor-alpha and interferon-gamma.

RESULTS

Although few results appear as significant during the various testing times, the dosage of some inflammation biomarkers, including CRP, at the very end of pregnancy or immediately after delivery could predict PPD. Interactions between inflammation and the corticotropic axis could explain PPD onset. Epigenetic mechanisms could lead to pro-inflammatory state. Several therapeutics provide interest due to their anti-inflammatory property.

CONCLUSIONS

Further studies are needed to assess these biomarkers value as predictive factors of PPD and to consider adjunct treatments to antidepressants. If this value is confirmed, the inflammatory marker dosage, in particular CRP, could help to provide early screening of women at risk of PPD, parallel of the clinical evaluation. A zinc supplementation could then be offered.

Predictors of Postpartum Depression: A Comprehensive Review of the Last Decade of Evidence

Postpartum depression (PPD) is one of the most frequent complications of childbirth affecting ~500,000 women annually (prevalence 10% to 15%). Despite the documented adverse outcomes for mother and child, there remains a great need to develop prospective approaches to identify women at risk. This review examines some of the best-characterized molecular and clinical risk factors for PPD. We illustrate that this is a growing literature but there remains a lack of reliable molecular predictors for PPD. Current best predictors are clinical assessments for psychiatric history and adverse life events, highlighting the need for increased depression screening across the perinatal period.

Postpartum Depression: Pathophysiology, Treatment, and Emerging Therapeutics

Postpartum depression (PPD) is common, disabling, and treatable. The strongest risk factor is a history of mood or anxiety disorder, especially having active symptoms during pregnancy. As PPD is one of the most common complications of childbirth, it is vital to identify best treatments for optimal maternal, infant, and family outcomes. New understanding of PPD pathophysiology and emerging therapeutics offer the potential for new ways to add to current medications, somatic treatments, and evidence-based psychotherapy. The benefits and potential harms of treatment, including during breastfeeding, are presented.

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.

Neurotrophins and neuroinflammation in fetuses exposed to maternal depression and anxiety disorders during pregnancy: a comparative study on cord blood

In recent years, there have been changes in the approach to maternal psychiatric disorders and their effects on the fetus, with the focus redirected to the search for biological markers. Neurotrophic factors and inflammatory processes have received particular attention in the past few years. According to the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), the study sample (n = 136) consisted of three groups: mothers with major depressive disorder (MDD group, n = 25), mothers with anxiety disorder (AD group, n = 18), and mothers without any psychiatric disorders (not diagnosed (ND) group, n = 93). During the delivery/cesarean section, a blood sample was obtained from the umbilical cord. Serum concentrations of BDNF, NT-3, FGF2, TNF-α, and neopterin were determined by enzyme-linked immunosorbent assay (ELISA), according to the manufacturer's procedure. Clinical and biochemical characteristics were assessed. We did not find a significant difference among the three study groups with regard to BDNF, NT-3, and TNF-α levels. The ANOVA test indicated statistically significant differences in FGF2 levels and neopterin between the study groups. The newborns of mothers with AD had significantly higher FGF2 levels and significantly higher neopterin levels when compared with those of mothers with MDD and healthy mothers. The present study sheds light on the effects of higher FGF2 and neopterin levels in fetuses exposed to AD. Our results should be replicated through further prospective studies with a larger sample size.

Heritability of plasma neopterin levels in the Old Order Amish

BACKGROUND

We examined the heritability of neopterin, a biomarker for cell-mediated immunity and oxidative stress, and potentially for psychiatric disorders, in the Old Order Amish.

METHODS

Plasma neopterin levels were determined in 2015 Old Order Amish adults. Quantitative genetic procedures were used to estimate heritability of neopterin.

RESULTS

Heritability of log-neopterin was estimated at 0.07 after adjusting for age, gender, and household (p=0.03). The shared household effect was 0.06 (p<0.02).

CONCLUSIONS

We found a low heritability of neopterin and small household effect, suggesting that non-household environmental factors are more important determinants of variance of neopterin levels in the Amish.

Seasonality of blood neopterin levels in the Old Order Amish

Seasonal changes in non-human animals and seasonal affective disorder (SAD) in humans are associated with immune activation in winter relative to summer. We intended to measure seasonal variation in neopterin, a marker of cellular immunity, and its interactions with gender and seasonality of mood. We studied 320 Amish from Lancaster, PA, USA (men = 128; 40%) with an average age [Standard deviation (SD)] of 56.7 (13.9) years. Blood neopterin level was measured with enzyme-linked immunosorbent assay (ELISA). Seasonality was measured with Seasonal Pattern Assessment Questionnaire (SPAQ). Statistical analysis included analysis of covariance (ANCOVAs) and multivariate linear regression. We also investigated interactions of seasonal differences in neopterin with gender, seasonality scores and estimation of SAD diagnosis. We found a significantly higher neopterin level in winter than in summer (p = 0.006). There were no significant gender or seasonality interactions. Our study confirmed the hypothesized higher neopterin level in winter. A cross sectional design was our major limitation. If this finding will be replicated by longitudinal studies in multiple groups, neopterin could be used to monitor immune status across seasons in demographically diverse samples, even if heterogeneous in gender distribution, and degree of seasonality of mood.

Perinatal Major Depression Biomarkers: A systematic review

Postpartum depression, now termed perinatal depression by the DSM-5, is a clinically relevant disorder reaching 15% of incidence. Although it is quite frequent and associated with high social dysfunction, only recently its underpinning biological pathways have been explored, while multiple and concomitant risk factors have been identified (e.g. psychosocial stress). Peripartum depression usually has its onset during the third trimester of pregnancy or in the postpartum, being one of the most common medical complications in new mothers. Purpose of the present review is to summarize the state of art of biological biomarkers involved in the pathogenesis of perinatal depression, in view of the fact that suboptimal prenatal milieu can induce permanent damage in subsequent offspring life and have a negative impact on mother-child relationship. Furthermore, parents' biological changes due to medical/psychiatric disorders or stress exposure could influence offspring life: a concept known as 'intergenerational transmission', acting by variations into gametes and the gestational uterine environment. Given the evidence that perinatal mental disorders involve risks for the mother and offspring, the search for reliable biomarkers in high-risk mothers actually represents a medical priority to prevent perinatal depression.

Microglia Transcriptome Changes in a Model of Depressive Behavior after Immune Challenge

Depression symptoms following immune response to a challenge have been reported after the recovery from sickness. A RNA-Seq study of the dysregulation of the microglia transcriptome in a model of inflammation-associated depressive behavior was undertaken. The transcriptome of microglia from mice at day 7 after Bacille Calmette Guérin (BCG) challenge was compared to that from unchallenged Control mice and to the transcriptome from peripheral macrophages from the same mice. Among the 562 and 3,851 genes differentially expressed between BCG-challenged and Control mice in microglia and macrophages respectively, 353 genes overlapped between these cells types. Among the most differentially expressed genes in the microglia, serum amyloid A3 (Saa3) and cell adhesion molecule 3 (Cadm3) were over-expressed and coiled-coil domain containing 162 (Ccdc162) and titin-cap (Tcap) were under-expressed in BCG-challenged relative to Control. Many of the differentially expressed genes between BCG-challenged and Control mice were associated with neurological disorders encompassing depression symptoms. Across cell types, S100 calcium binding protein A9 (S100A9), interleukin 1 beta (Il1b) and kynurenine 3-monooxygenase (Kmo) were differentially expressed between challenged and control mice. Immune response, chemotaxis, and chemokine activity were among the functional categories enriched by the differentially expressed genes. Functional categories enriched among the 9,117 genes differentially expressed between cell types included leukocyte regulation and activation, chemokine and cytokine activities, MAP kinase activity, and apoptosis. More than 200 genes exhibited alternative splicing events between cell types including WNK lysine deficient protein kinase 1 (Wnk1) and microtubule-actin crosslinking factor 1(Macf1). Network visualization revealed the capability of microglia to exhibit transcriptome dysregulation in response to immune challenge still after resolution of sickness symptoms, albeit lower than that observed in macrophages. The persistent transcriptome dysregulation in the microglia shared patterns with neurological disorders indicating that the associated persistent depressive symptoms share a common transcriptome basis.

Shen-Qi-Jie-Yu-Fang exerts effects on a rat model of postpartum depression by regulating inflammatory cytokines and CD4(+)CD25(+) regulatory T cells

BACKGROUND

Shen-Qi-Jie-Yu-Fang (SJF) is composed of eight Chinese medicinal herbs. It is widely used in traditional Chinese medicine for treating postpartum depression (PPD). Previous studies have shown that SJF treats PPD through the neuroendocrine mechanism.

AIM

To further investigate the effect of SJF on the immune system, including the inflammatory response system and CD4(+)CD25(+) regulatory T (Treg) cells.

MATERIALS AND METHODS

Sprague Dawley rats were used to create an animal model of PPD by inducing hormone-simulated pregnancy followed by hormone withdrawal. After hormone withdrawal, the PPD rats were treated with SJF or fluoxetine for 1, 2, and 4 weeks. Levels of Treg cells in peripheral blood were measured by flow cytometry analysis. Serum interleukin (IL)-1β and IL-6 were evaluated by enzyme-linked immunosorbent assay, and gene and protein expressions of IL-1RI, IL-6Rα, and gp130 in the hippocampus were observed by reverse-transcription polymerase chain reaction and Western blot.

RESULTS

Serum IL-1β in PPD rats increased at 2 weeks and declined from then on, while serum IL-6 increased at 1, 2, and 4 weeks. Both IL-1β and IL-6 were downregulated by SJF and fluoxetine. Changes in gene and protein expressions of IL-1RI and gp130 in PPD rats were consistent with changes in serum IL-1β, and were able to be regulated by SJF and fluoxetine. The levels of Treg cells were negatively correlated with serum IL-1β and IL-6, and were decreased in PPD rats. The levels of Treg cells were increased by SJF and fluoxetine.

CONCLUSION

Dysfunction of proinflammatory cytokines and Tregs in different stages of PPD was attenuated by SJF and fluoxetine through the modulation of serum concentrations of IL-1β and IL-6, expressions of IL-1RI, and gp130 in the hippocampus, and CD4(+)CD25(+) Treg cells in peripheral blood.

Mechanisms of Inflammation-Associated Depression: Immune Influences on Tryptophan and Phenylalanine Metabolisms

Metabolic parameters have a direct role in the regulation of immune cell function. Thereby the inflammation-induced metabolism of aromatic amino acids, most importantly of tryptophan and phenylalanine, plays a central role. In addition, neuropsychiatric conditions that go along with disorders that are characterized by acute or chronic inflammation, such as the development of depression, decreased quality of life or cognitive impairments, are connected to disturbed amino acid and subsequent neurotransmitter metabolism.The bioanalytical procedures for the determination of concentrations of tryptophan and phenylalanine and their respective first stable intermediates kynurenine and tyrosine as well as some analytical finesses and potential sources of errors are discussed in this chapter. Monitoring of these immunometabolic parameters throughout therapies in addition to biomarkers of immune response and inflammation such as neopterin can be useful to determine disease progression but also to plan psychiatric interventions timely, thus to establish personalized treatments.

The role of reproductive hormones in postpartum depression

Despite decades of research aimed at identifying the causes of postpartum depression (PPD), PPD remains common, and the causes are poorly understood. Many have attributed the onset of PPD to the rapid perinatal change in reproductive hormones. Although a number of human and nonhuman animal studies support the role of reproductive hormones in PPD, several studies have failed to detect an association between hormone concentrations and PPD. The purpose of this review is to examine the hypothesis that fluctuations in reproductive hormone levels during pregnancy and the postpartum period trigger PPD in susceptible women. We discuss and integrate the literature on animal models of PPD and human studies of reproductive hormones and PPD. We also discuss alternative biological models of PPD to demonstrate the potential for multiple PPD phenotypes and to describe the complex interplay of changing reproductive hormones and alterations in thyroid function, immune function, hypothalamic-pituitary-adrenal (HPA) axis function, lactogenic hormones, and genetic expression that may contribute to affective dysfunction. There are 3 primary lines of inquiry that have addressed the role of reproductive hormones in PPD: nonhuman animal studies, correlational studies of postpartum hormone levels and mood symptoms, and hormone manipulation studies. Reproductive hormones influence virtually every biological system implicated in PPD, and a subgroup of women seem to be particularly sensitive to the effects of perinatal changes in hormone levels. We propose that these women constitute a "hormone-sensitive" PPD phenotype, which should be studied independent of other PPD phenotypes to identify underlying pathophysiology and develop novel treatment targets.