Examination of the role of obesity in the association between childhood trauma and inflammation during pregnancy

Inflammation as a mediator between adverse childhood experiences and adult depression: A meta-analytic structural equation model

Exposure to adverse childhood experiences (ACEs) confers a higher risk of developing depression in adulthood, yet the mediation of inflammation remains under debate. To test this model, we conducted a systematic review and two-stage structural equation modelling meta-analysis of studies reporting correlations between ACEs before age 18, inflammatory markers and depression severity in adulthood. Scopus, Pubmed, Medline, PsycInfo, and CINAHL were searched up to 2 October 2023. Twenty-two studies reporting data on C-reactive protein (CRP, n = 12,935), interleukin-6 (IL-6, n = 4108), tumour necrosis factor-α (TNF-α, n = 2256) and composite measures of inflammation (n = 1674) were included. Unadjusted models revealed that CRP (β = 0.003, 95 % LBCI 0.0002 to 0.0068), IL-6 (β = 0.003, 95 % LBCI 0.001 to 0.006), and composite inflammation (β = 0.009, 95 % LBCI 0.004 to 0.018) significantly mediated the association between ACEs and adult depression. The mediation effects no longer survived after adjusting for BMI; however, a serial mediation model revealed that BMI and IL-6 sequentially mediated the association between ACEs and depression (β = 0.002, 95 % LBCI 0.0005 to 0.0046), accounting for 14.59 % and 9.94 % of the variance of IL-6 and depressive symptoms, respectively. Due to the cross-sectional nature of assessment of inflammation and depression findings should be approached with caution; however, results suggest that complex interactions of psychoneuroimmunological and metabolic factors underlie the association between ACEs and adulthood depression.

Inflammatory burden of adolescents with childhood maltreatment: results from baseline data of a school cohort

Increasing studies have investigated inflammatory burden of adults with childhood adversity, but less is known about how childhood maltreatment affects the inflammation level of adolescents. Baseline data of a school cohort of physical and mental health status and life experience survey on primary and secondary school students in Anhui Province, China was used. Childhood maltreatment of children and adolescents was assessed by Chinese version of Childhood Trauma Questionnaire-Short Form (CTQ-SF). Urine samples were collected to assess levels of soluble urokinase Plasminogen Activator Receptor (suPAR), C-reactive protein (CRP) and cytokines interleukin-6 (IL-6) by enzyme-linked immunosorbent assay (ELISA). Logistic regression was conducted to examine the association between childhood maltreatment exposure and risk of high inflammation burden. A total of 844 students were included with mean age 11.41 ± 1.57 years old. Adolescents with emotional abuse were significantly more likely to have high level of IL-6 (OR = 3.59, 95% CI 1.16-11.14). In addition, adolescents with emotional abuse were more likely to show high IL-6 and high suPAR combination (OR = 33.41, 95% CI 1.69-659.22), and high IL-6 and low CRP combination (OR = 4.34, 95% CI 1.29-14.55). Subgroup analyses showed that emotional abuse was associated with high IL-6 burden among boys or adolescents with depression. Childhood emotional abuse was positively associated with higher burden of IL-6. Early detection and prevention of emotional abuse for children and adolescents, especially for boys or adolescents with depression status, may be helpful for preventing elevated inflammatory burden and related health problems.

Inflammatory mediation of the relationship between early adversity and major depressive disorder: A systematic review

Early adverse experience is related to psychiatric illness that occurs decades later. The mechanisms underlying this phenomenon have not been fully identified. There is a translational and clinical literature linking early adversity with Major Depressive Disorder (MDD) and inflammation. We reviewed articles that examine whether inflammation mediates this relationship.

METHODS

Literature review of PUB MED, CINAHL and APA Psycinfo articles that explicitly examine inflammation as a mediator between early adversity and depression using ((((((((((adversity) OR (trauma)) OR (maltreatment)) OR (child abuse)) AND (inflammation)) OR (inflammatory cytokines)) OR (crp)) OR (il-6)) OR (tnf)) AND (mediates)) AND (depression))))))))) as key words.

RESULTS

2842 articles were initially identified. 1338 non-human studies were excluded and 512 more were filtered out as reviews. The remaining 992 titles and, when necessary, abstracts and manuscripts were reviewed and 956 were removed as being of other non-related phenomena. Four additional studies were added by hand searching the references of remaining studies. Out of these 40, 15 explicitly examined inflammation as a mediator of the relationship between early adversity and later depression. Approximately half (8/15) showed evidence that inflammation mediated the relationship between early adversity and depression. Sensitivity analyses showed that studies taking place in clinical populations, in youth and those that used the Adverse Childhood Events Scale to measure adversity, and IL-6 and TNF-α (as opposed to CRP) to measure inflammation were most likely to show mediation.

CONCLUSIONS

There is evidence to support the model of inflammation mediating the relationship between early adversity and depression. Certain measures in clinical populations appear more likely to support this model. Further study with more standardized, robust methods will help to answer this question more definitively and may elucidate a subtype of depression related to early adversity by alterations in immune function.

Maternal exposure to childhood maltreatment and adverse birth outcomes

Exposure to traumatic events during pregnancy may influence pregnancy and birth outcomes. Growing evidence suggests that exposure to traumatic events well before pregnancy, such as childhood maltreatment (CM), also may influence the course of pregnancy and risk of adverse birth outcomes. We aimed to estimate associations between maternal CM exposure and small-for-gestational-age birth (SGA) and preterm birth (PTB) in a diverse US sample, and to examine whether common CM-associated health and behavioral sequelae either moderate or mediate these associations. The Measurement of Maternal Stress (MOMS) Study was a prospective cohort study that enrolled 744 healthy English-speaking participants ≥ 18 years with a singleton pregnancy, who were < 21 weeks at enrollment, between 2013 and 2015. CM was measured via the Childhood Trauma Questionnaire (CTQ) and participants above the moderate/severe cut-off for any of the five childhood abuse and neglect scales were assigned to the CM-exposed group. Common CM-associated health (obesity, depressive symptoms, hypertensive disorders) and behavioral (substance use) sequelae were obtained from standardized questionnaires and medical records. The main outcomes included PTB (gestational age < 37 weeks at birth) and SGA (birthweight < 10%ile for gestational age) abstracted from the medical record. Multivariable logisitic regression was used to test associations between CM, sequeale, and birth outcomes, and both moderation and mediation by CM-related sequelae were tested. Data were available for 657/744 participants. Any CM exposure was reported by 32% of participants. Risk for SGA birth was 61% higher among those in the CM group compared to the non-CM group (14.1% vs. 7.6%), and each subsequent form of CM that an individual was exposed to corresponded with a 27% increased risk for SGA (aOR 1.27, 95% CI 1.05, 1.53). There was no significant association between CM and PTB (9.3% vs. 13.0%, aOR 1.07, 95% CI 0.58, 1.97). Of these sequelae only hypertensive disorders were associated with both CM and SGA and hypertensive disorders of pregnancy did not mediate the association between CM and SGA. Our findings indicate that maternal CM exposure is associated with increased risk for SGA birth and highlight the importance of investigating the mechanisms whereby childhood adversity sets the trajectory for long-term and intergenerational health issues.

Maternal early life stress is associated with pro-inflammatory processes during pregnancy

Early life stress (ELS) is common in the United States and worldwide, and contributes to the development of psychopathology in individuals with these experiences and their offspring. A growing body of research suggests that early life stress may contribute to adverse health partly through modulation of immune (and particularly inflammatory) responses. Therefore, increased maternal prenatal inflammation has been proposed as a mechanistic pathway by which the observed cross-generational effects of parental early life stress on child neuropsychiatric outcomes may be exerted. We examined associations between early life stress and molecular markers of inflammation (specifically pro-inflammatory gene expression and receptor-mediated transcription factor activity) and a commonly studied circulating marker of inflammation (C-Reactive Protein) in a diverse group of women in or near their third trimester of pregnancy, covarying for age, race/ethnicity, BMI, concurrent infection, concurrent perceived stress, and per capita household income. Mothers who experienced higher levels of early life stress had significantly increased pro-inflammatory (NF-κB) and decreased anti-viral (IRF) transcription factor activity. Transcripts that were up or down regulated in mothers with high ELS were preferentially derived from both CD16+ and CD16- monocytes. Early life stress was not associated with elevated CRP. Taken together, these findings provide preliminary evidence for an association between ELS and a pro-inflammatory transcriptional phenotype during pregnancy that may serve as a mechanistic pathway for cross-generational transmission of the effects of early life stress on mental and physical health.

The association between victimization and inflammation: A meta-analysis

BACKGROUND

To meta-analyze the existing studies examining the association of childhood and adulthood victimization with inflammation and to explore the moderating variables that affect these relationships.

METHODS

Relevant work published before 28th February 2021 was identified by searching five major databases. We analyzed the cross-sectional data extracted from cross-sectional and longitudinal studies using the random-effects model to estimate the correlation (r) as the pooled effect size and further conducted subgroup analyses and sensitivity analyses.

RESULTS

A total of 37 articles finally met the inclusion criteria, including studies for C-reactive protein (CRP) (k = 23; N_CRP = 11,780), interleukin-6 (IL-6) (k = 31; N_IL-6 = 8943), and tumor necrosis factor-alpha (TNF-α) (k = 14; N_TNF-α = 4125). Overall, victimization has a significantly positive association with inflammation, with a small effect size (r = 0.122). Specifically, effect sizes were the largest for TNF-a (r = 0.152), followed by IL-6 (r = 0.119), and CRP (r = 0.084). Additionally, the effect sizes for victimization against children were r = 0.145 (k = 6) for childhood victimization - childhood inflammation, and r = 0.139 (k = 27) for childhood victimization - adulthood inflammation, which appear to be larger than that of victimization against adults (r = 0.039; k = 2).

LIMITATIONS

Only a small number of studies on adult victimization were included. In addition, we only analyzed the cross-sectional relationship and did not have sufficient data to compare different types of victimization and single vs. multiple victimizations.

CONCLUSIONS

Victimization is associated with a heightened inflammatory response. As victimization against children may have a stronger effect than victimization against adults, prevention of victimization targeting the childhood period may be necessary. Studies with more robust methodologies (i.e., representative, longitudinal, and multi-country designs) are needed to confirm these findings and to unpack the underlying mechanisms.

IL-6 and IL-8: An Overview of Their Roles in Healthy and Pathological Pregnancies

Interleukin-6 (IL-6) is an acknowledged inflammatory cytokine with a pleiotropic action, mediating innate and adaptive immunity and multiple physiological processes, including protective and regenerative ones. IL-8 is a pro-inflammatory CXC chemokine with a primary function in attracting and activating neutrophils, but also implicated in a variety of other cellular processes. These two ILs are abundantly expressed at the feto-maternal interface over the course of a pregnancy and have been shown to participate in numerous pregnancy-related events. In this review, we summarize the literature data regarding their role in healthy and pathological pregnancies. The general information related to IL-6 and IL-8 functions is followed by an overview of their overall expression in cycling endometrium and at the feto-maternal interface. Further, we provide an overview of their involvement in pregnancy establishment and parturition. Finally, the implication of IL-6 and IL-8 in pregnancy-associated pathological conditions, such as pregnancy loss, preeclampsia, gestational diabetes mellitus and infection/inflammation is discussed.

Influence of adipose tissue immune dysfunction on childhood obesity

In recent decades, a dramatic rise has been observed in the prevalence of obesity in childhood and adolescence, along with an increase in fetal microsomia rates. The increased risk of obesity during this key period in development negatively affects the health of the individual later in life. Immune cells residing and recruited to white adipose tissue have been highlighted as important factors contributing to the pathogenesis of childhood obesity. Immune dysfunction in the context of obesity begins early in childhood, which is different from the pathological characteristics and influencing factors of adipose immunity in adults. Here, we explore the current understanding of the roles of childhood and early life events that result in high risks for obesity by influencing adipose tissue immune dysfunction under the pathological condition of obesity. Such knowledge will help in determining the mechanisms of childhood and early life obesity in efforts to ameliorate chronic inflammation-related metabolic diseases.

Exposure to childhood maltreatment and systemic inflammation across pregnancy: The moderating role of depressive symptomatology

BACKGROUND

Childhood maltreatment (CM) has long-term consequences for dysregulation of the immune system which is particularly pronounced when mental and physical health sequelae have manifested. Higher proinflammatory state has been shown in non-pregnant state in association with CM as well as with depression, one of the most frequent and pernicious psychiatric sequelae of CM. During pregnancy, however, this association is less clear. Given the important role of maternal inflammatory state during pregnancy for fetal, pregnancy, and birth outcomes, we sought to examine the association between CM and proinflammatory state during pregnancy considering the moderating role of maternal depressive symptoms characterized serially across pregnancy.

METHODS

A prospective, longitudinal study of 180 healthy pregnant women was conducted with serial assessments in early (12.98 ± 1.71 weeks gestation), mid (20.53 ± 1.38 weeks gestation) and late (30.42 ± 1.4 weeks gestation) pregnancy. Maternal history of CM was assessed with the Childhood Trauma Questionnaire (CTQ) and the total score was used as an indicator of CM experience. Maternal depressive symptoms were assessed at each pregnancy visit with the Center for Epidemiologic Studies Depression Scale (CES-D). Serum concentrations of tumor necrosis factor (TNF)-α and interleukin (IL)-6 were obtained at each pregnancy visit and combined to a composite maternal proinflammatory score. Linear mixed effects models were employed to assess the association between CTQ score, CES-D score, and proinflammatory score during pregnancy, adjusting for potential confounders.

RESULTS

Gestational age was associated with the proinflammatory score (B = 0.02; SE = 0.00; p < .001), indicating an increase in inflammation across gestation. Neither CTQ score nor depressive symptoms were independently associated with the proinflammatory score (ps > 0.28). However, the interaction between CTQ score and depressive symptoms was associated with the proinflammatory score (B = 0.03, SE = 0.01, p < .05), indicating higher inflammation across pregnancy with increasing levels of depressive symptoms during pregnancy in women with higher CTQ scores. Exploratory analyses suggested that this interaction was mainly driven by CTQ subscale scores assessing experiences of abuse rather than neglect.

CONCLUSIONS

These findings suggest a moderating role of maternal depressive symptoms during pregnancy on the association of early life stress with inflammation and thus highlight the importance of the timely assessment of both CM exposure and depressive symptoms which might allow for the development of targeted and individualized interventions to impact inflammation during pregnancy and to ameliorate the detrimental long-term effects of CM. The current findings add to a better understanding of the prenatal biological pathways that may underlie intergenerational transmission of maternal CM.

Childhood adversity, prenatal depression, and maternal inflammation across pregnancy

Background

To examine whether change in neutrophil-lymphocyte ratio, a marker of systemic inflammation, differs by childhood adversity and prenatal depression.

Methods

Prenatal complete blood count data were used to calculate neutrophil-lymphocyte ratio in first and third trimesters. The Adverse Childhood Experiences scale measured childhood adversity, and the Patient Health Questionnaire-9 measured depression. This is a secondary analysis of a study of predictors of risk for sleep-disordered breathing.

Results

Participants were 98 pregnant women, mean age 30 years (SD = 5), mean body mass index of 35 kg/m² (SD = 7), 61% identified as white, and 28% identified as Hispanic. Women who reported childhood sexual abuse history displayed greater increase in neutrophil-lymphocyte ratio over pregnancy relative to women without childhood sexual abuse. Change in neutrophil-lymphocyte ratio across pregnancy did not differ by prenatal depression.

Conclusion

Experiences of sexual abuse in childhood may impact markers of systemic inflammation in pregnancy.

Stress-Related Mental Health Disorders and Inflammation in Pregnancy: The Current Landscape and the Need for Further Investigation

Many studies have focused on psychoimmunological mechanisms of risk for stress-related mental health disorders. However, significantly fewer studies have focused on understanding mechanisms of risk for stress-related disorders during pregnancy, a period characterized by dramatic changes in both the innate and adaptive immune systems. The current review summarizes and synthesizes the extant literature on the immune system during pregnancy, as well as the sparse existing evidence highlighting the associations between inflammation and mood, anxiety, and fear-related disorders in pregnancy. In general, pregnant persons demonstrate lower baseline levels of systemic inflammation, but respond strongly when presented with an immune challenge. Stress and trauma exposure may therefore result in strong inflammatory responses in pregnant persons that increases risk for adverse behavioral health outcomes. Overall, the existing literature suggests that stress, trauma exposure, and stress-related psychopathology are associated with higher levels of systemic inflammation in pregnant persons, but highlight the need for further investigation as the existing data are equivocal and vary based on which specific immune markers are impacted. Better understanding of the psychoimmunology of pregnancy is necessary to reduce burden of prenatal mental illness, increase the likelihood of a successful pregnancy, and reduce the intergenerational impacts of prenatal stress-related mental health disorders.

Co-occurrence of preconception maternal childhood adversity and opioid use during pregnancy: Implications for offspring brain development

Understanding of the effects of in utero opioid exposure on neurodevelopment is a priority given the recent dramatic increase in opioid use among pregnant individuals. However, opioid abuse does not occur in isolation-pregnant individuals abusing opioids often have a significant history of adverse experiences in childhood, among other co-occurring factors. Understanding the specific pathways in which these frequently co-occurring factors may interact and cumulatively influence offspring brain development in utero represents a priority for future research in this area. We highlight maternal history of childhood adversity (CA) as one such co-occurring factor that is more prevalent among individuals using opioids during pregnancy and which is increasingly shown to affect offspring neurodevelopment through mechanisms beginning in utero. Despite the high incidence of CA history in pregnant individuals using opioids, we understand very little about the effects of comorbid prenatal opioid exposure and maternal CA history on fetal brain development. Here, we first provide an overview of current knowledge regarding effects of opioid exposure and maternal CA on offspring neurodevelopment that may occur during gestation. We then outline potential mechanistic pathways through which these factors might have interactive and cumulative influences on offspring neurodevelopment as a foundation for future research in this area.

Inflammation and early life stress: An updated review of childhood trauma and inflammatory markers in adulthood

Inflammation, as a neurobiological consequence of childhood trauma, has frequently been reported across research, however, recent investigations suggest this relationship may be dependent on specificities such as type of trauma, type of inflammatory marker, and additional mediatory variables - such as body mass index (BMI), age, and sex. As an updated version of a previous review by Baumeister et al., the current review comprised a search of PubMed, which identified 37 articles that collectively assessed 4 inflammatory markers (CRP, IL-6, TNFα and IL-1β). A review of the studies revealed predominantly non-significant associations between childhood trauma and elevated levels of all inflammatory markers in adulthood. However, in line with previous research, discrepancies in significance arose when considering type of trauma, type of inflammatory marker, and additional variables. Compared to neglect, abuse showed greater significant associations with elevated inflammatory markers in adulthood, though this was dependent on the individual subtypes (emotional, physical or sexual). Mediation analyses reported BMI as a significant mediator, though, when controlled for, no significant differences were found. Sex differences were reported but investigations were sparse. Future research should investigate the mediatory role of sex differences in the inflammatory effects of childhood trauma. Many studies in the review were restricted by use of the same trauma measure - the Childhood Trauma Questionnaire. To assess greater variety of trauma types, future studies should utilize other standardized measures to explore these avenues.

Maternal Serum Cytokine Concentrations in Healthy Pregnancy and Preeclampsia

The maternal immune response is essential for successful pregnancy, promoting immune tolerance to the fetus while maintaining innate and adaptive immunity. Uncontrolled, increased proinflammatory responses are a contributing factor to the pathogenesis of preeclampsia. The Th1/Th2 cytokine shift theory, characterised by bias production of Th2 anti-inflammatory cytokine midgestation, was frequently used to reflect the maternal immune response in pregnancy. This theory is simplistic as it is based on limited information and does not consider the role of other T cell subsets, Th17 and Tregs. A range of maternal peripheral cytokines have been measured in pregnancy cohorts, albeit the changes in individual cytokine concentrations across gestation is not well summarised. Using available data, this review was aimed at summarising changes in individual maternal serum cytokine concentrations throughout healthy pregnancy and evaluating their association with preeclampsia. We report that TNF-α increases as pregnancy progresses, IL-8 decreases in the second trimester, and IL-4 concentrations remain consistent throughout gestation. Lower second trimester IL-10 concentrations may be an early predictor for developing preeclampsia. Proinflammatory cytokines (TNF-α, IFN-γ, IL-2, IL-8, and IL-6) are significantly elevated in preeclampsia. More research is required to determine the usefulness of using cytokines, particularly IL-10, as early biomarkers of pregnancy health.

Maternal childhood adversity and inflammation during pregnancy: Interactions with diet quality and depressive symptoms

Inflammatory processes are a candidate mechanism by which early adversity may be biologically embedded and subsequently lead to poorer health outcomes; in pregnancy, this has been posited as a pathway for intergenerational transmission of adversity. Studies in non-pregnant adults suggest that factors such as mood, diet, BMI, and social support may moderate associations between childhood trauma history and inflammation in adulthood, though few studies have examined these associations among pregnant women. In a sample of healthy pregnant women (N = 187), we analyzed associations between maternal childhood adversity, including maltreatment and non-optimal caregiving experiences, with circulating Interleukin-6 (IL-6) levels during trimesters 2 (T2) and 3 (T3) of pregnancy. We also assessed whether these associations were moderated by psychosocial and lifestyle factors including depressive symptoms, social support, physical activity, and diet quality. History of childhood maltreatment was not associated with IL-6 in either T2 or T3 of pregnancy, either independently or in interaction with depressive symptom severity. However, in there was a significant positive association between childhood maltreatment and IL-6 in Trimester 2 in the context of poorer diet quality (p = 0.01), even after adjusting for BMI. Additionally, the quality of caregiving women received in childhood was associated with levels of IL-6 in Trimester 3, but only via interaction with concurrent depressive symptoms (p = 0.02). These findings provide evidence that for those with a history of childhood adversity, levels of inflammatory cytokines in pregnancy may be more sensitive to depressive symptoms and diet quality.

Pro-inflammatory immune cell gene expression during the third trimester of pregnancy is associated with shorter gestational length and lower birthweight

PROBLEM

Altered maternal immune function predicts risk for shorter gestation and low birthweight. Few studies examine associations between prenatal immune cell gene expression and gestational length or birthweight. No studies examine which cell types drive associations. The purpose of this study is to explore associations between peripheral blood immune cell gene expression and gestational length and birthweight, using transcript origin analysis.

METHOD OF STUDY

Eighty-nine women were drawn from the Community Child Health Network cohort. Third trimester maternal dried blood spots were used for genome-wide transcriptional (mRNA) profiling. Gestational length and birthweight were obtained from medical charts. Covariates were age, race/ethnicity, pre-pregnancy body mass index, smoking, gestational age at blood sampling, and pregnancy infections. Associations between gene expression profiles and gestational length and birthweight were tested using general linear models. The Transcription Element Listening System (TELiS) bioinformatics analysis quantified upstream transcription factor activity. Transcript origin analysis identified leukocyte subsets mediating observed effects.

RESULTS

Shorter gestation was predicted by increased NF-kB (TFBM ratio = -0.582 ± 0.172, P < .001) and monocyte activity (diagnosticity score = 0.172 ± 0.054, P < .001). Longer gestation was associated with increased dendritic cell activity (diagnosticity score = 0.194 ± 0.039, P < .001). Increased AP-1 activity predicted lower birthweight (TFBM ratio = -0.240 ± 0.111, P = .031). Dendritic cells and CD4+ and CD8+ T cells predicted birthweight-related gene expression differences (diagnosticity score P's < 0.021).

CONCLUSION

Higher third trimester pro-inflammatory gene expression predicted shorter gestation and lower birthweight. Variations in monocyte and dendritic cell biology contributed to both effects, and T-cell biology contributed to higher birthweight. These analyses clarify the role of myeloid/lymphoid lineage immune regulation in pregnancy outcomes.

Elevated pro-inflammatory gene expression in the third trimester of pregnancy in mothers who experienced stressful life events

BACKGROUND

Stress exposure is associated with risk for adverse pregnancy outcomes, potentially in part through dysregulated immune and inflammatory activity. Evidence suggests that stress during pregnancy is associated with inflammation during pregnancy, consistent with risk for preterm birth. However, research has not tested whether complementary changes are reflected in immune cell gene expression, or upstream regulation of inflammation. The purpose of this study was to test associations between preconception and prenatal stress exposure and third trimester immune cell gene expression, focusing specifically on sets of genes previously linked to stress in non-pregnant samples: Pro-inflammatory genes, and antiviral and antibody genes.

METHODS

A sample of 116 low-income, diverse women was recruited from 5 U.S. sites by the Community Child and Health Network at the birth of a child. This study is of the subgroup of women who became pregnant again over the two-year follow-up period, and provided information on stressful life events that occurred both preconception and during the third trimester of the subsequent pregnancy. Dried blood spots (DBS) were collected in the third trimester of pregnancy, and used for gene expression analysis.

RESULTS

Women with more prenatal stressful life events had higher expression of pro-inflammatory genes when compared to those with fewer life events, and the effect was driven by increased activation of pro-inflammatory transcription factors, NF-κB and AP-1. Preconception stressful life event exposure was not associated with gene expression profiles. When entered into models simultaneously, only prenatal stressful life events were associated with up-regulation of pro-inflammatory genes. No differences between high or low stress groups emerged for antiviral or antibody genes.

CONCLUSIONS

Prenatal stress exposure was associated with up-regulated pro-inflammatory gene expression during pregnancy, and increased activity of NF-κB and AP-1. In contrast, stress occurring preconception was not associated with gene expression. These results are consistent with the hypothesis that stress-induced activation of pro-inflammatory transcriptional pathways in pregnancy, but not earlier, may increase risk for inflammation-driven adverse pregnancy outcomes.

Innate immune activation and depressive and anxious symptoms across the peripartum: An exploratory study

BACKGROUND

There are complex associations between immune function and mental illness, yet studies in the perinatal period focus primarily on individual inflammatory markers and depressive symptoms only, cross-sectionally. We sought to examine associations between both depressive and anxious symptoms and immune activation longitudinally across the peripartum.

METHODS

We measured mood (Beck Depression Inventory, BDI-1 A) and anxiety (State-Trait Anxiety Inventory, STATE) and levels of 23 cytokines at 5 points in pregnancy and postpartum in 51 women. Within subject cytokine trajectories over time by depressive and anxious symptom grouping were assessed using linear mixed effects models with random intercept and slope. We also undertook an exploratory cluster analysis based on third trimester cytokine values.

RESULTS

Based on categorical BDI scores, IL-6 (p <  0.001), IL-15 (p =  0.047), GCSF (p = 0.003), and CCL3 (p < .001) were significantly different across time, with IL-6 (p <  0.001), IL-15 (p =  0.003), and CCL3 (p <  0.001) higher at the third trimester visit in more depressed subjects. Based on categorical STATE scores, GM-CSF significantly decreased across pregnancy for the less anxious group (p = 0.016), but not for the more anxious, and CCL3 (p = 0.017), CXCL8 (p = 0.011), and IL-6 (p < 0.001) were higher at the third trimester visit for more anxious subjects. In exploratory cluster analysis based on cytokine level, there were no differences in mood or anxiety scores, but significant differences by race/ethnicity and overweight/obesity status. Women with higher pro-inflammatory cytokine values are more likely to be Hispanics (69.2% vs. 21.4%, p =  0.015), but less likely to be African American (23.1% vs. 60.7%, p = 0.015) or overweight/obese (25% vs. 69.2%, p =  0.016) compared to women with lower pro-inflammatory cytokine values.

CONCLUSION

We identified a pro-inflammatory burst at the third trimester, indicative of innate immune activation, in women with higher levels of both depressive and anxious symptoms, as well as differences in pro-inflammatory changes across time. We also found significant differences in cytokine levels by race, ethnicity, and overweight/obesity status. These results point the way toward future longitudinal work that considers race/ethnicity, timing, and weight status, and evaluates perinatal mood and anxiety disorders in the context of changing immune functioning across the peripartum.

Childhood adversity impact on gut microbiota and inflammatory response to stress during pregnancy

BACKGROUND

Adverse childhood experiences (ACEs), such as abuse or chronic stress, program an exaggerated adult inflammatory response to stress. Emerging rodent research suggests that the gut microbiome may be a key mediator in the association between early life stress and dysregulated glucocorticoid-immune response. However, ACE impact on inflammatory response to stress, or on the gut microbiome, have not been studied in human pregnancy, when inflammation increases risk of poor outcomes. The aim of this study was to assess the relationships among ACE, the gut microbiome, and cytokine response to stress in pregnant women.

METHODS

Physically and psychiatrically healthy adult pregnant women completed the Adverse Childhood Experiences Questionnaire (ACE-Q) and gave a single stool sample between 20 and 26 weeks gestation. Stool DNA was isolated and 16S sequencing was performed. Three 24-hour food recalls were administered to assess dietary nutrient intake. A subset of women completed the Trier Social Stress Test (TSST) at 22-34 weeks gestation; plasma interleukin-6 (IL-6), interleukin-1β (IL-1β), high sensitivity C-reactive protein (hsCRP), tumor necrosis factor α (TNF-α), and cortisol were measured at four timepoints pre and post stressor, and area under the curve (AUC) was calculated.

RESULTS

Forty-eight women completed the ACE-Q and provided stool; 19 women completed the TSST. Women reporting 2 or more ACEs (high ACE) had greater differential abundance of gut Prevotella than low ACE participants (q = 5.7 × 10^-13). Abundance of several gut taxa were significantly associated with cortisol, IL-6, TNF-α and CRP AUCs regardless of ACE status. IL-6 response to stress was buffered among high ACE women with high intake of docosahexaenoic acid (DHA) (p = 0.03) and eicosapentaenoic acid (EPA) (p = 0.05).

DISCUSSION

Our findings suggest that multiple childhood adversities are associated with changes in gut microbiota composition during pregnancy, and such changes may contribute to altered inflammatory and glucocorticoid response to stress. While preliminary, this is the first study to demonstrate an association between gut microbiota and acute glucocorticoid-immune response to stress in a clinical sample. Finally, exploratory analyses suggested that high ACE women with high dietary intake of ω-3 polyunsaturated fatty acids (PUFAs) had a dampened inflammatory response to acute stress, suggesting potentially protective effects of ω-3s in this high-risk population. Given the adverse effects of inflammation on pregnancy and the developing fetus, mechanisms by which childhood adversity influence the gut-brain axis and potential protective factors such as diet should be further explored.

Pathways linking childhood abuse history and current socioeconomic status to inflammation during pregnancy

Women who have experienced significant adversities during childhood and adulthood are at risk for excessive inflammation during pregnancy, but the mechanisms are unclear. Using structural equation modeling, we examined pathways from childhood abuse history and current socioeconomic status (SES) to inflammatory markers through indicators of health risk, recent stressors, and psychological distress in 214 women assessed at mid-pregnancy (5-31 weeks gestation). Self-reported data on socioeconomic indicators, childhood trauma history, pre-pregnancy body mass index (BMI), smoking, sleep quality, interpersonal conflict, recent life events, perceived stress, and depressive symptoms were collected, and serum levels of C-reactive protein (CRP) and interleukin (IL)-6 were determined. In separate models, pre-pregnancy BMI, sleep quality, and interpersonal conflict statistically explained the relationship between adversity and inflammation. These three intermediate variables were then entered into a multiple mediation analysis to examine unique effects. Childhood abuse history and current SES both demonstrated significant indirect effects on CRP through pre-pregnancy BMI, and current SES showed a significant indirect effect on IL-6 through all intermediate variables. When examining each indirect pathway individually, pre-pregnancy BMI and interpersonal conflict emerged as parallel pathways by which low current SES leads to elevated IL-6; the indirect pathway through sleep quality was no longer significant. Pre-pregnancy BMI and interpersonal conflict are two independent mechanisms by which adversity is associated with increased inflammation during pregnancy. Women who have been exposed to significant adversity may be at particular risk for obesity, sleep disruption, and interpersonal conflict, with implications for immune dysregulation during pregnancy.