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Differential effects of active versus passive coping on secretory immunity

This study examined the acute immunological effects of two laboratory stressors, expected to evoke distinct patterns of cardiac autonomic activity; namely an “active coping” time-paced memory test, and a “passive coping” stressful video showing surgical operations. We measured salivary S-IgA, IgA-subclasses (IgA1, IgA2), and secretory component (SC). SC is responsible for the transport of S-IgA across the epithelium, and thus a rate-determining step in S-IgA secretion. Thirty-two male undergraduates were subjected to both stressors and a control video (a didactic television program). The memory test induced a typical “fight-flight” response, characterized by increases in heart rate and blood pressure in association with a decrease in cardiac preejection period (PEP) and vagal tone. The surgical video produced a “conservation-withdrawal”-like response, characterized by an enhanced vagal tone, a decrease in heart rate, and a moderate sympathetic coactivation (as indicated by a shortened PEP and an increased systolic pressure). The memory test induced an increase in the concentration and, to a lesser extent, in the output of S-IgA, IgA], and SC. The output of IgA2 was not significantly affected. For the surgical video, a different pattern emerged: During stressor exposure S-IgA remained unaffected, against the background of a small increase in SC output. However, 10 min after the surgical video S-IgA levels had decreased. This decrease in S-IgA was paralleled by a decrease in IgA1, but not IgA2. We conclude that acute stress can have both enhancing and suppressive effects on secretory immunity, the IgA1 subclass in particular. The mechanisms that underlie these divergent responses may include stressor-specific patterns of autonomic activation.

Maternal long-chain polyunsaturated fatty acid status during early pregnancy: Association with child behavioral problems and the role of autonomic nervous system activity

Background & aims
The prenatal environment, including availability of critical nutrients, has a profound impact on offspring development. The present study examined the association between maternal long-chain polyunsaturated fatty acid (LC-PUFA) status during pregnancy and later child behavioral problems at the age of 5–6 years. In light of evidence of autonomic nervous system (ANS) dysregulation in some behavioral problems, study further tested if the above association is statistically mediated by cardiac ANS activity.
Methods
Data was collected as part of the Amsterdam Born Children and their Development-study and complete data were available for 1717 mothers and their offspring. Maternal LC-PUFA status was assessed during early pregnancy (mean gestation = 12.7, SD = 2.5 weeks) and quantified as levels of docosahexenoic acid (DHA), arachidonic acid (AA), eicosapentaenoic acid (EPA), as well as the ratio of n-6:n-3 fatty acids. Child emotional problems and peer problems (internalizing problems), as well as conduct problems and inattention/hyperactivity (externalizing problems), were assessed using the Strengths and Difficulties Questionnaire as rated by the mother and teacher at 5–6 years. Child cardiac respiratory sinus arrhythmia (RSA), pre-ejection period (PEP), and heart rate (HR) were utilized as measures of ANS activity at 5–6 years.
Results
The results confirmed an association between maternal LC-PUFA status and internalizing behavioral problems as rated by the mother, as shown for DHA (β = −0.11;p < 0.01), EPA (β = -0.22;p < 0.05), and n-6:n-3 LC-PUFA (β = 0.17;p < 0.01). Statistical mediation was only demonstrated for HR. No associations were observed between LC-PUFA status and externalizing behavioral problems. Conclusions The present results are consistent with a role of maternal LC-PUFA status in internalizing behavioral problems as rated by the mother. These results were not observed when problem behavior was rated by the teacher. Analyses did not yield strong evidence supporting ANS activity as a possible mediator in this relationship.

Acute stress reactivity and intrusive memory development: a randomized trial using an adjusted trauma film paradigm

Understanding the neurobiological and cognitive processes underlying the development of posttraumatic stress disorder (PTSD) and its specific symptoms may facilitate preventive intervention development. Severe traumatic stress and resulting biological stress system activations can alter contextual memory processes. This may provide a neurobiological explanation for the occurrence of intrusive memories following trauma. Investigating the associations between temporal aspects and individual variation in peri- and post-traumatic hypothalamic pituitary adrenal (HPA) axis and sympathetic nervous system (SNS) stress reactivity and memory processing may increase our understanding of intrusive symptom development. The experimental trauma film paradigm is commonly used for this purpose but lacks robust SNS and HPA axis activation. Here, we performed an RCT to investigate the effect of an adjusted trauma film paradigm containing an added brief psychosocial stressor on HPA and SNS stress reactivity throughout the experiment and intrusive memory frequency in the following week in healthy males (N = 63, mean age = 22.3). Secondary, we investigated effects on film-related declarative memory accuracy and intrusion-related characteristics, and associations between acute HPA and SNS stress reactivity, film-related memory, glucocorticoid receptor functioning and intrusion frequency and characteristics. Participants were randomized to the socially-evaluated cold pressor test (seCPT n = 29) or control condition (warm water n = 34) immediately prior to a trauma film. Linear Mixed Models revealed increased acute SNS and cortisol reactivity, lower recognition memory accuracy and more intrusions that were more vivid and distressing during the following week in the seCPT compared to control condition. Linear regression models revealed initial associations between cortisol and alpha amylase reactivity during the experimental assessment and subsequent intrusions, but these effects did not survive multiple comparison corrections. Thus, with this adjustment, we increased the translational value of the trauma film paradigm as it appears to elicit a stronger stress response that is likely more comparable to real-life trauma. The adapted paradigm may be useful to investigate individual variation in biological and cognitive processes underlying early post-trauma PTSD symptoms and could advance potential preventive interventions.