Stress-induced redistribution of immune cells--from barracks to boulevards to battlefields: a tale of three hormones--Curt Richter Award winner

The maternal leukocyte count at admission for labor is indicative of early maternal postpartum infectious morbidity and adverse neonatal outcome

OBJECTIVES

Investigate the association between maternal leukocyte count at admission for labor and postpartum infectious maternal morbidity (PPIM) following vaginal delivery.

STUDY DESIGN

Retrospective cohort study, 2005-2017. Afebrile women, term, singleton, vaginal delivery included. Maternal leukocyte/differential at admission for labor and 24 h postpartum were analyzed as continuous values and quintiles. Pre/postpartum difference (Δleukocyte) was calculated. The primary outcome was maternal PPIM, early and late. The secondary outcome was adverse neonatal outcomes (ANO).

RESULTS

58,174 eligible deliveries out of168,979 (34.4 %); 1068 (1.8 %) women with PPIM. The rate rose linearly from 1.4 % for the lowest admission for labor leukocyte quantile to 2.7 % for the highest quantile, p for trend <0.001. The women with early PPIM had significantly higher admission levels of leukocytes (mean): 12.04 ± 3.43 vs. 11.18 ± 2.86 × 10^3/μl; neutrophils, 9.48 ± 3.46 vs. 8.40 ± 2.67 × 10^3/μl; and monocytes 0.76 ± 0.25 vs. 0.72 ± 0.23 × 10^3/μl); p < 0.001 for all. The mean leukocyte count for women with PPIM diagnosis, including only postpartum fever, was 12.06 ± 2.64; significantly higher than in the non-PPIM group, p = 0.014. A Δleukocyte value of >3.7 × 10^3/μl is significantly associated with PPIM, aOR 2.10 [1.82-2.41]. No significant association between leukocyte count or Δleukocyte and maternal readmission rate due to infectious complications. 386 neonates (0.7 %) had records of ANO and 64 neonates (0.1 %) had records of neonatal sepsis, positive linear association; p for trend < 0.001. The maternal Δleukocyte value of >3.7 × 10^3/μl was found to be significantly associated with the risk for ANO, aOR 1.5[1.19-1.90].

CONCLUSION

In healthy women, an elevated level of the leukocyte count at admission for labor and the Δleukocyte are significant risk predictors of PPIM and ANO.

Adaptive Stress Coping in Awake Bruxism

Numerous studies have analyzed the relationship between psychological factors and bruxism. However, the data are often obscured by the lack of precise diagnostic criteria and the variety of the psychological questionnaires used. The purpose of this study is to determine the association between awake bruxism and psychological factors (anxiety, depression, sociability, stress coping, and personality traits). With this aim, 68 participants (13 males) completed a battery of psychological questionnaires, a self-reported bruxism questionnaire, and a clinical examination. Based on their scores on the bruxism questionnaire and the clinical examination, subjects were divided into two groups. Subjects who met the criteria for “probable awake bruxism” were assigned to the case group (n = 29, five males). The control group (n = 39, nine males) was composed of subjects who showed no signs or symptoms of bruxism in the examination nor in the questionnaire. The probable awake bruxism group presented significantly higher levels of trait and state anxiety, symptoms of somatization, and neuroticism than the control group. Despite this, and when their problem coping strategies were considered, awake bruxers showed higher levels in Positive Reappraisal (p < 0.05), a strategy generally considered as adaptive. In conclusion, although awake bruxers in our study showed larger levels of anxiety, somatization, and neuroticism, they also displayed more adapted coping strategies, while according to previous data TMD patients (which generally also present high levels of anxiety, somatization and neuroticism) might tend to present less adaptive coping styles. Thus, awake bruxism may play a positive role in stress coping, which would be compatible with the hypothesis of mastication as a means of relieving psychological tension. This finding should be further confirmed by future research comparing TMD patients with definitive awake bruxers and controls and using larger and more representative samples.

Arrival cortisol measurement in veal calves and its association with body weight, protein fractions, animal health and performance

Male dairy calves are exposed to an accumulation of transport, social and environmental stressors while transferred to fattening units. As a consequence, calves show high cortisol concentrations upon arrival at the veal facility. Whether cortisol levels as measured on arrival can be associated with animal health, welfare and production results is currently unknown. The first objective of this prospective cohort study was to determine possible associations of arrival serum cortisol concentration with health and production variables of veal calves and other arrival predictors like body weight and γ-globulin concentration. The second aim was to investigate potential clustering of arrival risk factors in veal calves for developing bovine respiratory disease (BRD) based on arrival body weight, serum cortisol concentration, total protein and protein fractions. In total, 105 male Holstein calves from two consecutive production cycles in a single, commercial white veal farm were blood sampled directly at arrival on the farm to determine serum cortisol, total protein and protein fractions. All calves were weighed the day after arrival and clinical signs, average daily weight gain (ADG) and carcass weight were collected. Also, all calves of both production cohorts were repeatedly examined by thoracic ultrasonography at the onset of group respiratory disease symptoms (2-3 weeks after arrival) and four weeks later. Linear and logistic mixed models together with k-means clustering were used for statistical analyses. Calves showed on average high, but individually variable serum cortisol concentrations (mean value = 96.6 ng/mL ± standard deviation (SD) = 48.8; Range (R) = 50.0-317 ng/mL). Arrival cortisol, body weight and γ-globulin content were not significantly associated. Serum cortisol and albumin concentrations at arrival were associated with chronic, unresponsive pneumonia. For each increase of serum cortisol concentration by 10 ng/mL, the odds for lung consolidation of ≥1 cm in depth at the second ultrasonography increased, odds ratio (OR) = 1.03 (95 % confidence interval (CI) = 1.01-1.06; P < 0.050). For every decrease in serum albumin concentration by 1g/L, the OR for developing pneumonia was 1.23 (95 % CI= 1.04-1.46; P < 0.015). Additionally, two clusters of calves were identified based upon arrival status: a low risk cluster with below average stress-induced cortisol values, above average body weight, no acute phase response (APR) and no failure of passive immune transfer (FPIT), and a high risk cluster with above average cortisol values, below average body weight, APR and FPIT. High risk calves had higher odds for developing clinical BRD (OR= 3.88 (95 % CI=1.20-12.53; P < 0.020)) and lung consolidation ≥1 cm in depth at week 6-7 after arrival (OR= 3.93 (95 % CI=1.34-11.53; P < 0.013)). Avoiding high cortisol levels upon arrival of calves is important for animal welfare, but also for reduction of the prevalence of chronic, unresponsive pneumonia and the associated need for (repeated) antimicrobial treatment and production losses.

Unique maternal immune and functional microbial profiles during prenatal stress

Maternal stress during pregnancy is widespread and is associated with poor offspring outcomes, including long-term mental health issues. Prenatal stress-induced fetal neuroinflammation is thought to underlie aberrant neurodevelopment and to derive from a disruption in intrauterine immune homeostasis, though the exact origins are incompletely defined. We aimed to identify divergent immune and microbial metagenome profiles of stressed gestating mice that may trigger detrimental inflammatory signaling at the maternal-fetal interface. In response to stress, maternal glucocorticoid circuit activation corresponded with indicators of systemic immunosuppression. At the maternal-fetal interface, density of placental mononuclear leukocytes decreased with stress, yet maternal whole blood leukocyte analysis indicated monocytosis and classical M1 phenotypic shifts. Genome-resolved microbial metagenomic analyses revealed reductions in genes, microbial strains, and metabolic pathways in stressed dams that are primarily associated with pro-inflammatory function. In particular, disrupted Parasutterella excrementihominis appears to be integral to inflammatory and metabolic dysregulation during prenatal stress. Overall, these perturbations in maternal immunological and microbial regulation during pregnancy may displace immune equilibrium at the maternal-fetal interface. Notably, the absence of and reduction in overt maternal inflammation during stress indicates that the signaling patterns driving fetal outcomes in this context are more nuanced and complex than originally anticipated.

Effect of β-Alanine Supplementation on Monocyte Recruitment and Cognition During a 24-Hour Simulated Military Operation

Wells, AJ, Varanoske, AN, Coker, NA, Kozlowski, GJ, Frosti, CL, Boffey, D, Harat, I, Jahani, S, Gepner, Y, and Hoffman, JR. Effect of β-alanine supplementation on monocyte recruitment and cognition during a 24-hour simulated military operation. J Strength Cond Res 34(11): 3042-3054, 2020-Sustained military operations (SUSOPs) result in psychological stress and cognitive dysfunction, which may be related to the recruitment of classical monocytes into the brain. This study examined the effect of beta-alanine (BA) on cognition and monocyte recruitment during a simulated 24-hour SUSOP. Nineteen healthy men ingested 12-g/d BA or placebo for 14 days before an SUSOP. Monocyte chemoattractant protein-1 (MCP-1), C-C chemokine receptor-2 (CCR2), and macrophage-1-antigen (CD11b) expression were assessed through multiplex assay and flow cytometry. Psychological stress and cognition were assessed through Automated Neuropsychological Assessment Metrics (ANAM). A composite measure of cognition (COGcomp) was generated from throughput scores extracted from 7 ANAM cognitive tests. Assessments occurred at baseline (0H), 12 hours (12H), 18 hours (18H), and 24 hours (24H). Significance was accepted at p ≤ 0.05. No significant effect of BA was noted for any variable (p's > 0.05). The frequency and severity of symptoms of psychological stress increased significantly at 18 and 24H compared with 0 and 12H (p's < 0.05). COGcomp decreased significantly at 18 and 24H compared with 0 and 12H (p's ≤ 0.001). MCP-1 peaked at 18H was significantly lower at 24H compared with 18H but remained elevated at 24H compared with 0H (p's < 0.001). CCR2 expression was significantly lower at 12 (p = 0.031), 18, and 24H (p's < 0.001). CD11b expression was significantly higher at 12H (p = 0.039) and 24H (p's = 0.003). MCP-1 was negatively associated with COGcomp (β = -0.395, p = 0.002, r2 = 0.174). Neither CCR2 or CD11b was related to COGcomp (p's > 0.05). Cognitive dysfunction during SUSOPs is related to serum concentrations of MCP-1 but is not influenced by BA supplementation.

Investigating the True Effect of Psychological Variables Measured Prior to Arthroplastic Surgery on Postsurgical Outcomes: A P-Curve Analysis

Patients' presurgical psychological profiles have been posited to predict pain and function following arthroplastic surgery of the hip and knee. Nevertheless, findings are conflicting, and this may be rooted in biased reporting that makes the determination of evidential value difficult. This ambiguity may have negative consequences for researchers and governmental agencies, as these rely on findings to accurately reflect reality. P-Curve analyses were used to establish the presence of evidential value and selective reporting in a sample of studies examining the effect of presurgical psychological predictors on outcomes following knee and hip arthroplastic surgery. A systematic search of the literature revealed 26 relevant studies. The examined sets of studies indicate that there is evidential value for the effect of depression on pain intensity and function, anxiety on pain intensity and function, pain catastrophizing on pain intensity, as well as the combined effects of all psychological predictors on pain intensity and function. The presence of evidential value was inconclusive for the effect of optimism on pain intensity. There were no signs that any results were influenced by biased reporting. The results highlight the importance of patients' psychological profiles in predicting surgical outcomes, which represent a promising avenue for future treatment approaches. PERSPECTIVE: The effects of P-hacking are difficult to detect and might be at the root of conflicting findings pertaining to the predictive properties of presurgical psychological variables on postsurgical outcomes. P-Curve analysis allows the determination of evidential value underlying these relationships and detection of P-hacking to ensure that findings are not the result of selective reporting.

Immunological effects of Chondrus armatus carrageenans and their low molecular weight degradation products

Ability of high molecular weight (HMW) κ- and λ-carrageenans of the red marine algae Chondrus armatus and their low molecular weight degradation products (LMWDPs) (0.7-20 and 10-170 kDa respectively) to influence functional properties (motility and phagocytosis) of murine peritoneal macrophages was assessed in this study as an in vitro and a weeklong feeding experiment. We demonstrated that, with an exception of one, all carrageenan samples at 100 μg/ml increased cellular motility and dose-dependently decreased phagocytic activity; LMWDPs of λ-carrageenan suppressed motility and had no effect on phagocytosis. Oral administration of all the carrageenan samples at 100 μg/kg/day for 7 days to mice had no effect on their clinical appearance, body weight, weight of their liver, spleen or thymus or development of noticeable changes to their inner organs. All samples induced a shift of the cell composition of the peritoneal cavity towards macrophages. Consumption of LMWDPs of κ-carrageenan resulted in development of leukopenia, however, no changes to relative WBC count were introduced by either of the samples. All samples decreased murine peritoneal macrophages phagocytic activity, with λ-samples possessing higher efficacy than their κ-counterparts; all LMWDPs stimulated peritoneal macrophages motility, with κ-samples possessing higher efficacy than their λ-counterparts In conclusion, we have shown that κ- and λ-carrageenans of the C. armatus and their LMWDPs suppress phagocytotic activity of peritoneal macrophages under both in vitro and in vivo conditions. This allows them to be viewed as pharmacologically active substances andpropagates the need for their further investigation as such.

Stress and coping in women with breast cancer:unravelling the mechanisms to improve resilience

Breast cancer diagnosis, surgery, adjuvant therapies and survivorship can all be extremely stressful. In women, concerns about body image are common as a result of the disease and can affect interpersonal relationships, possibly leading to social isolation, increasing the likelihood for mood disorders. This is particularly relevant as women are at greater risk to develop anxiety and depressive symptoms in response to highly stressful situations. Here we address the mechanisms and the pathways activated as a result of stress and contributing to changes in the pathophysiology of breast cancer, as well as the potential of stress management factors and interventions in buffering the deleterious effects of chronic stress in a gender perspective. An improved understanding of the biological mechanisms linking stress-management resources to health-relevant biological processes in breast cancer patients could reveal novel therapeutic targets and help clarifying which psychosocial interventions can improve cancer outcomes, ultimately offering a unique opportunity to improve contemporary cancer treatments.

Ecoimmune reallocation in a native lizard in response to the presence of invasive, venomous fire ants in their shared environment

Exposure to stressors over prolonged periods can have fitness-relevant consequences, including suppression of immune function. We tested for effects of presence of an invasive species threat on a broad panel of immune functions of a coexisting lizard. Eastern fence lizards (Sceloporus undulatus) have been exposed to invasive fire ants (Solenopsis invicta) for over 80 years. Fire ants sting and envenomate lizards, causing physiological stress, but we do not have a comprehensive understanding of the broad immune consequences of lizard exposure to fire ant presence. We conducted a suite of immune measures on fence lizards caught from areas with long histories of fire ant invasion and lizards from areas not yet invaded by fire ants. The effect of fire ant presence on immunity varied depending on the immune component measured: within fire ant invaded areas, some portions of immunity were suppressed (lymphocytic cell-mediated immunity, complement), some were unaffected (phagocytic respiratory burst, natural antibodies), and some were enhanced (anti-fire ant immunoglobulin M, basophils) compared to within uninvaded areas. Rather than fire ants being broadly immunosuppressing, as generally assumed, the immune response appears to be tailored to this specific stressor: the immune measures that were enhanced are important to the lizards' ability to handle envenomation, whereas those that were unaffected or suppressed are less critical to surviving fire ant encounters. Several immune measures were suppressed in reproductive females when actively producing follicles, which may make them more susceptible to immunosuppressive costs of stressors such as interactions with fire ants.

Association between increased neutrophil-to-lymphocyte ratio and postoperative delirium in elderly patients with total hip arthroplasty for hip fracture

BACKGROUND

Delirium is a common complication in elderly patients with total hip arthroplasty (THA) for hip fracture. The mechanism of postoperative delirium (POD) is associated with the neuroinflammatory process. The aim of this study was to the incidence and perioperative risk factors of POD and investigate whether NLR could serve as a potential marker for POD in elderly patients with THA for hip fracture.

METHODS

This was a multicenter prospective study, we included elderly patients with THA for hip fracture under general anesthesia. Receiver operating characteristic (ROC) curve was performed to identify the optimal cut point of NLR for POD. The relationship between NLR and POD was analyzed by multivariable analysis.

RESULTS

Seven hundred eighty patients (mean age 73.33 ± 7.66) were eligible for inclusion in the study. 23.33% (182/780) of patients had POD. ROC curve analysis showed that the optimal cut point of NLR for POD was NLR ≥ 3.5. Compared with no POD, higher NLR, older age, diabetes, and higher neutrophil count were more likely in patients with POD(P < 0.05). Multivariate logistic regression analysis showed that NLR ≥ 3.50 [adjusted odds ratio(aOR), 3.93; confidence interval (CI), 2.47-6.25; P < 0.001)], older age (aOR, 1.04; 95%CI, 1.02-1.07; P = 0.001), diabetes (aOR, 1.58; 95% CI, 1.06-2.36; P = 0.025),higher neutrophil count (aOR, 1.25; 95%CI, 1.15-1.35; P < 0.001) were associated with increased risk of POD.

CONCLUSIONS

Older age, diabetes, higher neutrophil count, and NLR ≥ 3.5 were independent risk factors for POD, and NLR can be used as a potential marker for prediction of delirium in elderly patients with THA for hip fracture.

SARS-CoV-2 (COVID-19) and the Endocrine System

As SARS-CoV-2 (COVID-19) overtakes the world, causing moderate to severe disease in about 15% of infected patients, COVID-19 is also found to have widespread effects throughout the body with a myriad of clinical manifestations including the endocrine system. This manuscript reviews what is known about the impact of COVID-19 on the pathophysiology and management of diabetes (both outpatient and inpatient) as well as pituitary, adrenal, thyroid, bone, and gonadal function. Findings in this area are evolving, and long-term effects of infection remain an active area of further research.

Mid-life microbiota crises: middle age is associated with pervasive neuroimmune alterations that are reversed by targeting the gut microbiome

Male middle age is a transitional period where many physiological and psychological changes occur leading to cognitive and behavioural alterations, and a deterioration of brain function. However, the mechanisms underpinning such changes are unclear. The gut microbiome has been implicated as a key mediator in the communication between the gut and the brain, and in the regulation of brain homeostasis, including brain immune cell function. Thus, we tested whether targeting the gut microbiome by prebiotic supplementation may alter microglia activation and brain function in ageing. Male young adult (8 weeks) and middle-aged (10 months) C57BL/6 mice received diet enriched with a prebiotic (10% oligofructose-enriched inulin) or control chow for 14 weeks. Prebiotic supplementation differentially altered the gut microbiota profile in young and middle-aged mice with changes correlating with faecal metabolites. Functionally, this translated into a reversal of stress-induced immune priming in middle-aged mice. In addition, a reduction in ageing-induced infiltration of Ly-6C^hi monocytes into the brain coupled with a reversal in ageing-related increases in a subset of activated microglia (Ly-6C⁺) was observed. Taken together, these data highlight a potential pathway by which targeting the gut microbiome with prebiotics can modulate the peripheral immune response and alter neuroinflammation in middle age. Our data highlight a novel strategy for the amelioration of age-related neuroinflammatory pathologies and brain function.

Retrospective analysis of the lifetime endocrine response of southern right whale calves to gull wounding and harassment: A baleen hormone approach

Physiological measurements are informative in assessing the relative importance of stressors that potentially impact the health of wildlife. Kelp Gulls, Larus dominicanus (KG), resident to the region of Península Valdés, Argentina, have developed a unique behavior of landing on the backs of southern right whale adults and calves, Eubalaena australis (SRW), where they feed on their skin and blubber. This parasitic behavior results in large open wounds on the dorsal surface of the whale. Coincidently, the SRW population off the coast of Península Valdés has experienced elevated calf mortality. We quantified levels of glucocorticoids and thyroid hormone extracted from baleen of dead calves to evaluate, retrospectively, the endocrine response of whale calves to gull wounding and harassment. Baleen accumulates hormones as it grows, allowing evaluation of long-term trends in physiological condition. While glucocorticoids (GCs) are known to increase in response to stressors such as disturbance, the metabolic hormone triiodothyronine (T₃) has been shown to decrease under sustained food deprivation but is largely unaffected by disturbance stress. We quantified lifetime patterns of GCs and T₃ in baleen recovered at necropsy from 36 southern right whale calves with varying severity of wounding from KGs. GC levels in baleen correlated positively with the degree of wounding, while T₃ levels remained stable irrespective of the severity of the wounding. Our results suggest no evidence of malnutrition in low vs. severely wounded whales. However, the positive correlation of GCs with wound severity indicates that heavily wounded calves are suffering high levels of physiological stress before they die. This suggests that KG wounding may have contributed to the high southern right whale calf mortality observed in the Península Valdés region of Argentina.

On the winter enhancement of adaptive humoral immunity: hypothesis testing in desert hamsters (Phodopus roborovskii: Cricetidae, Rodentia) kept under long-day and short-day photoperiod

We tested the winter immunity enhancement hypothesis (WIEH) on male desert hamsters (Phodopus roborovskii) kept under long-day (LD) and short-day (SD) photoperiods. We assumed that under SD in a laboratory, the adaptive humoral immune responsiveness to the antigenic challenge would be enhanced due to the lack of winter physical stressors and food shortages and/or because of the action of an endogenous winter bolstering mechanism, while under LD the immune responsiveness would be suppressed by the activity of the reproductive system. The results support the WIEH in part. We did not find a difference in antibody production in response to sheep erythrocytes between SD and LD hamsters, but SD males had the lower number of granulocytes and the higher number of lymphocytes in white blood cell counts. Reproductive activity was lower in SD males. These males demonstrated an increase in their mass-specific resting metabolic rate, their mass-specific maximal metabolic rate and their level of cortisol. The result of a generalized linear model analysis indicates the negative effect on secondary immunoresponsiveness to sheep erythrocytes of mid-ventral gland size, the organ characterizing individual reproductive quality, and designates a tradeoff between antibody production and reproductive effort. The mass-independent maximal metabolic rate also negatively affected antibody production, indicating a tradeoff between maximal aerobic performance and the adaptive immune function. The higher stress in SD males seems to be the most likely reason for the lack of the effect of daylight duration on antibody production.

Reflections on Bruce S. McEwen's contributions to stress neurobiology and so much more

The authors highlight, from a firsthand perspective, Bruce S. McEwen's seminal influence on the field of stress neurobiology and beyond, and how these investigations have yielded important insights, principles and critical questions that continue to guide stress research today. Featured are discussion of: 1) the important inverted-U relationship between stress/glucocorticoids and optimal physiological function, 2) stress adaptation and the role of adaptive stress responses, 3) mechanisms by which the short-term stress response promotes heightened immune function and immunity, and 4) the far reaching impact of the theoretical framework of allostasis and allostatic load-concepts that have created new bridges between stress physiology, biomedical sciences, health psychology and sociology.

Predictive value of preoperative and postoperative peripheral lymphocyte difference in hepatitis B virus-related hepatocellular cancer patients: Based on the analysis of dynamic nomogram

BACKGROUND

Inflammation plays an important role in the progression and prognosis of hepatocellular carcinoma (HCC). Our aim is to explore the prognostic value of preoperative and postoperative peripheral lymphocyte differences and to develop a dynamic prognosis nomogram in hepatitis B virus-related HCC patients.

METHODS

Important indicators related to overall survival (OS) are screened out by Cox proportional hazard models. The receiver operating characteristic curves, decision curve analysis curves, net reclassification improvement, and integrated discrimination improvement were used to evaluate the performance of the model.

RESULTS

Lymphocyte (L) difference was an independent risk factor. It was further verified that the performance of the nomogram was significantly improved after the L difference was incorporated into the nomogram. The nomogram generated had the area under curves of 0.779, 0.775, and 0.793 at 3, 5, and 7 years after surgery, respectively. Our nomogram models showed significantly better performance in predicting the HCC prognosis compared to other models. And online webserver and scoring system table was built based on the proposed nomogram for convenient clinical use.

CONCLUSIONS

It is newly found that L difference is an effective predictor of OS, and the nomogram based on this indicator can accurately predict the prognosis of HCC patients.

Stress and Alzheimer's disease: A senescence link?

Chronic stress has been shown to promote numerous aging-related diseases, and to accelerate the aging process itself. Of particular interest is the impact of stress on Alzheimer's disease (AD), the most prevalent form of dementia. The vast majority of AD cases have no known genetic cause, making it vital to identify the environmental factors involved in the onset and progression of the disease. Age is the greatest risk factor for AD, and measures of biological aging such as shorter telomere length, significantly increase likelihood for developing AD. Stress is also considered a crucial contributor to AD, as indicated by a formidable body of research, although the mechanisms underlying this association remain unclear. Here we review human and animal literature on the impact of stress on AD and discuss the mechanisms implicated in the interaction. In particular we will focus on the burgeoning body of research demonstrating that senescent cells, which accumulate with age and actively drive a number of aging-related diseases, may be a key mechanism through which stress drives AD.

Neuroimmune Mechanisms and Sex/Gender-Dependent Effects in the Pathophysiology of Mental Disorders

Innate and adaptive immune mechanisms have emerged as critical regulators of CNS homeostasis and mental health. A plethora of immunologic factors have been reported to interact with emotion- and behavior-related neuronal circuits, modulating susceptibility and resilience to mental disorders. However, it remains unclear whether immune dysregulation is a cardinal causal factor or an outcome of the pathologies associated with mental disorders. Emerging variations in immune regulatory pathways based on sex differences provide an additional framework for discussion in these psychiatric disorders. In this review, we present the current literature pertaining to the effects that disrupted immune pathways have in mental disorder pathophysiology, including immune dysregulation in CNS and periphery, microglial activation, and disturbances of the blood-brain barrier. In addition, we present the suggested origins of such immune dysregulation and discuss the gender and sex influence of the neuroimmune substrates that contribute to mental disorders. The findings challenge the conventional view of these disorders and open the window to a diverse spectrum of innovative therapeutic targets that focus on the immune-specific pathophenotypes in neuronal circuits and behavior. SIGNIFICANCE STATEMENT: The involvement of gender-dependent inflammatory mechanisms on the development of mental pathologies is gaining momentum. This review addresses these novel factors and presents the accumulating evidence introducing microglia and proinflammatory elements as critical components and potential targets for the treatment of mental disorders.

Sleep enhances numbers and function of monocytes and improves bacterial infection outcome in mice

Sleep strongly impacts both humoral and cellular immunity; however, its acute effects on the innate immune defense against pathogens are unclear. Here, we elucidated in mice whether sleep affects the numbers and functions of innate immune cells and their defense against systemic bacterial infection. Sleep significantly increased numbers of classical monocytes in blood and spleen of mice that were allowed to sleep for six hours at the beginning of the normal resting phase compared to mice kept awake for the same time. The sleep-induced effect on classical monocytes was neither caused by alterations in corticosterone nor myelopoiesis, bone marrow egress or death of monocytes and did only partially involve Gαi-protein coupled receptors like chemokine receptor 2 (CCR2), but not the adhesion molecules intercellular adhesion molecule 1 (ICAM-1) or lymphocyte function-associated antigen 1 (LFA-1). Notably, sleep suppressed the expression of the clock gene Arntl in splenic monocytes and the sleep-induced increase in circulating classical monocytes was abrogated in Arntl-deficient animals, indicating that sleep is a prerequisite for clock-gene driven rhythmic trafficking of classical monocytes. Sleep also enhanced the production of reactive oxygen species by monocytes and neutrophils. Moreover, sleep profoundly reduced bacterial load in blood and spleen of mice that were allowed to sleep before systemic bacterial infection and consequently increased survival upon infection. These data provide the first evidence that sleep enhances numbers and function of innate immune cells and therewith strengthens early defense against bacterial pathogens.

Coping strategies and stress-induced natural killer cell redistribution in women with eating disorders

BACKGROUND

Patients with eating disorders (ED) are very sensitive and responsive to psychosocial stress. Stress response includes changes in immune cell distribution and may be modulated by the capability to cope with stressors. Thus, the present study sought to analyze the association between coping strategies and immune response (natural killer [NK] cell redistribution following psychosocial stress) in patients with anorexia nervosa (AN) and bulimia nervosa (BN) and healthy controls (HC).

METHOD

Twenty-four AN patients, 29 BN patients, and 58 HC were studied. A multidimensional assessment tool, the COPE Inventory, was used to assess coping strategies. The number of NK cells was quantified in peripheral blood before and after the application of the Trier Social Stress Test (TSST). Potentially mediating variables, such as weight status, severity of eating pathology, depression, anxiety, and impulsivity were controlled.

RESULTS

The three groups differed in intensity and direction of cell redistribution: The TSST was followed in BN patients by a significant decrease in the number of NK cells, whereas HC displayed a moderate decrease and AN a clear increase. Specific correlations between coping strategies and NK cell mobilization were found, especially in BN patients (positive for "planning" and negative for "substance abuse").

CONCLUSION

Recognition and subsequent modification of the dysfunctional coping strategies used by patients with ED could contribute to improving their immune status, strengthening their resilience and increasing their ability to overcome the disease.

Social Safety Theory: A Biologically Based Evolutionary Perspective on Life Stress, Health, and Behavior

Social Safety Theory hypothesizes that developing and maintaining friendly social bonds is a fundamental organizing principle of human behavior and that threats to social safety are a critical feature of psychological stressors that increase risk for disease. Central to this formulation is the fact that the human brain and immune system are principally designed to keep the body biologically safe, which they do by continually monitoring and responding to social, physical, and microbial threats in the environment. Because situations involving social conflict, isolation, devaluation, rejection, and exclusion historically increased risk for physical injury and infection, anticipatory neural-immune reactivity to social threat was likely highly conserved. This neurocognitive and immunologic ability for humans to symbolically represent and respond to potentially dangerous social situations is ultimately critical for survival. When sustained, however, this multilevel biological threat response can increase individuals' risk for viral infections and several inflammation-related disease conditions that dominate present-day morbidity and mortality.

Determination of Psychological Stress, Serum Immune Parameters, and Cortisol Levels in Patients With Human Papilloma Virus

PURPOSE

Because the results of studies investigating the relation between human papilloma virus (HPV) infection and the effects of psychological stress are inconsistent, this study was conducted to expand on previous research by analyzing patient stress levels, serum immune parameters, and cortisol levels in patients with clinical HPV manifestations. It also looked for differences in clinical manifestations of HPV depending on patient level of experienced stress.

METHODS

This cross-sectional study included 213 subjects (94 women and 119 men aged ≥18 years; average age, 41 years) with clinical manifestations of HPV infection (165 subjects with extragenital manifestations and 48 with genital manifestations) who were treated at the Department of Dermatovenerology, Karlovac General Hospital, from January 1, 2012, to December 31, 2015. Psychological, neurohormonal and immune parameters (serum values of leukocytes, alpha₂-globulins, beta-globulins, albumins, and proteins), and serum cortisol levels were analyzed. Questionnaires were used to determine patients' perception of stress: the Recent Life Changes Questionnaire, the Perceived Stress Scale, and the Brief Cope Test. One group of subjects had confirmed stressful experiences, defined by the Recent Life Changes Questionnaire as a period of 1 year with at least 500 life change units; the control group included patients with no significant stressful experiences.

FINDINGS

Patients with confirmed significant stress experience had a statistically significant higher degree of perception of stress. There were no statistically significant differences in terms of the impact of stress on clinical HPV manifestations (genital and extragenital), sex, lesional duration, or recurrence. In patients with significant stress experience, significantly higher values of leukocytes (6.68 × 10⁹/L), alpha₂-globulins (6.85 g/L), and beta-globulins (7.33 g/L) were observed. Adaptive coping and a lower perception of stress significantly reduced the chances of having extragenital manifestations by 2.63 times. A higher perception of stress significantly increased the likelihood of genital manifestations.

IMPLICATIONS

Although this study found that stress increased the values of leukocytes, alpha₂-globulins, and beta-globulins, no evidence was found that it affected clinical manifestations of HPV infection. The redundancy of the immune system could account for this finding. This study is among the first to investigate the correlation between psychological, neurohormonal, and immune indicators of stress.

Local sympathetic neurons promote neutrophil egress from the bone marrow at the onset of acute inflammation

The sympathetic nervous system plays critical roles in the differentiation, maturation and recruitment of immune cells under homeostatic conditions, and in responses to environmental stimuli, although its role in the migratory control of immune cells during acute inflammation remains unclear. In this study, using an advanced intravital bone imaging system established in our laboratory, we demonstrated that the sympathetic nervous system locally regulates neutrophil egress from the bone marrow for mobilization to inflammatory foci. We found that sympathetic neurons were located close to blood vessels in the bone marrow cavity; moreover, upon lipopolysaccharide (LPS) administration, local sympathectomy delayed neutrophil egress from the bone marrow and increased the proportion of neutrophils that remained in place. We also showed that vascular endothelial cells produced C-X-C motif chemokine ligand 1 (CXCL1), which is responsible for neutrophil egress out of the bone marrow. Its expression was up-regulated during acute inflammation, and was suppressed by β-adrenergic receptor blockade, which was accompanied with inhibition of neutrophil egress into the systemic circulation. Furthermore, systemic β-adrenergic signaling blockade decreased the recruitment of neutrophils in the lung under conditions of acute systemic inflammation. Taken together, the results of this study first suggested a new regulatory system, wherein local sympathetic nervous activation promoted neutrophil egress by enhancing Cxcl1 expression in bone marrow endothelial cells in a β-adrenergic signaling-dependent manner, contributing to the recruitment of neutrophils at the onset of inflammation in vivo.

Modifiable Cardiovascular Risk, Hematopoiesis, and Innate Immunity

Unhealthy diet, lack of exercise, psychosocial stress, and insufficient sleep are increasingly prevalent modifiable risk factors for cardiovascular disease. Accumulating evidence indicates that these risk factors may fuel chronic inflammatory processes that are active in atherosclerosis and lead to myocardial infarction and stroke. In concert with hyperlipidemia, maladaptive immune system activities can contribute to disease progression and increase the probability of adverse events. In this review, we discuss recent insight into how the above modifiable risk factors influence innate immunity. Specifically, we focus on pathways that raise systemic myeloid cell numbers and modulate immune cell phenotypes, reviewing hematopoiesis, leukocyte trafficking, and innate immune cell accumulation in cardiovascular organs. Often, relevant mechanisms that begin with lifestyle choices and lead to cardiovascular events span multiple organ systems, including the central nervous, endocrine, metabolic, hematopoietic, immune and, finally, the cardiovascular system. We argue that deciphering such pathways provides not only support for preventive interventions but also opportunities to develop biomimetic immunomodulatory therapeutics that mitigate cardiovascular inflammation.

Fatigue in inflammatory rheumatic disorders: pathophysiological mechanisms

Today, inflammatory rheumatic disorders are effectively treated, but many patients still suffer from residual fatigue. This work presents pathophysiological mechanisms of fatigue. First, cytokines can interfere with neurotransmitter release at the preterminal ending. Second, a long-term increase in serum concentrations of proinflammatory cytokines increase the uptake and breakdown of monoamines (serotonin, noradrenaline and dopamine). Third, chronic inflammation can also decrease monoaminergic neurotransmission via oxidative stress (oxidation of tetrahydrobiopterin [BH4]). Fourth, proinflammatory cytokines increase the level of enzyme indoleamine-2, 3-dioxygenase activity and shunt tryptophan away from the serotonin pathway. Fifth, oxidative stress stimulates astrocytes to inhibit excitatory amino acid transporters. Sixth, astrocytes produce kynurenic acid that acts as an antagonist on the α7-nicotinic acetylcholine receptor to inhibit dopamine release. Jointly, these actions result in increased glutamatergic and decreased monoaminergic neurotransmission. The above-described pathophysiological mechanisms negatively affect brain functioning in areas that are involved in fatigue.

Effect of Dog Presence on Stress Levels in Students under Psychological Strain: A Pilot Study

As university students face many stressful situations, especially during the examination period, this study focused on the use of animal-assisted activities (AAAs) with a dog as a means of relieving students’ stress before a final exam. The aim was to determine whether a 10-min interaction with a dog affected subjectively evaluated stress and mood, objective blood pressure, and heart rate. Ninety-three female students (mean age = 22.5 years; standard deviation = 3.8 years) were divided into three groups according to their preference. The first group underwent AAAs (n = 26), the second group chose a relaxation technique (n = 28), and the last one was a control group (n = 39). Physiological values were measured using a pressure gauge and the subjective feelings of stress and mood were evaluated by the Likert scale 1–5. The AAA group showed significant improvement after 10 min of interaction in both mood and stress, with no change in heart rate and blood pressure. The remaining groups showed a significant decrease in blood pressure, but not in heart rate, with different evaluations of mood and stress. AAAs with a dog appear to be effective in improving students’ mood and stress without affecting their physiological parameters.

High intensity interval exercise increases the frequency of peripheral PD-1+ CD8+ central memory T-cells and soluble PD-L1 in humans

Exercise can exert anti-inflammatory effects in an intensity-dependent manner; however, the mechanisms mediating these effects are continually being established. Programme Death Receptor-1 (PD-1) is a membrane bound receptor that maintains immune tolerance by dampening immune cell interactions, such as those mediated by cytotoxic T-cell lymphocytes (CD8⁺). The aim of this study was to characterise sub-populations of CD8⁺ T-cells with regards to their expression of PD-1 before and immediately after exercise. Interleukin (IL)-6, soluble PD-1 (sPD-1) and its ligand (sPD-L1) were also quantified in plasma. Eight individuals (mean ​± ​SD: age 29 ​± ​5 years; BMI 24.2 ​± ​3.4 ​kg ​m²; V˙O_2max 44.5 ​± ​6.4 ​ml ​kg⁻¹·min⁻¹) undertook two time and energy-matched cycling bouts in a counterbalanced study design: one of moderate intensity (MOD) and a bout of high intensity interval exercise (HIIE). Both MOD and HIIE increased the number, but not the proportion of circulating CD8⁺ PD-1+ cells, with no differences between trials. Within the CD8⁺ PD-1+ pool, the expression of PD-1 increased on central memory cells following HIIE only (fold change: MOD 1.0 vs HIIE +1.4), as well the concentration of CD8+PD-1+ memory cells within the circulation (cells/uL: MOD -0.4 vs HIIE +5.8). This response composed a very small part of the exercise-induced CD8⁺ lymphocytosis (Pre-Ex: 0.38% to Post-Ex: 0.69%; p ​> ​0.05). sPD-L1 and IL-6 concentration increased in tandem following MOD and HIIE (r ​= ​0.57; P ​= ​0.021), with a reciprocal decline in sPD-1 observed. The current data demonstrate that PD-1+ CD8⁺ lymphocytes were mobilised following both MOD and HIIE. Both the number of central memory CD8⁺ T-cells expressing PD-1 and the expression level on these cells were increased following HIIE only. This intensity-dependent phenotypic response, in conjunction with increased circulatory sPD-L1 may represent an aspect of the anti-inflammatory response to exercise and warrants further investigation.

•

PD-1 is a membrane-bound T-cell receptor that regulates immune tolerance.

•

We explored phenotypic changes in PD-1+ T-cells after exercise.

•

Circulating PD-1+ CD8⁺ T-cells increased after moderate and high intensity interval exercise (HIIE).

•

Central memory CD8⁺ T-cell number and expression increased after HIIE only.

•

Post-exercise levels of soluble PD-1 Ligand increased and correlated with IL-6.

Deficiency of O-linked-glycosylation regulates activation of T cells and aggravates Concanavalin A-induced liver injury

OBJECTIVE

Protein glycosylation is involved in immunological recognition and immune cell activation. The role of O-glycosylation in Concanavalin A (Con A)-induced autoimmune hepatitis (AIH) was elucidated in the present study.

METHODS

Mice were intravenously injected with Con A (10 mg/kg) to establish an AIH mouse model. Here, 24 h prior to administration of Con A, experimental mice were intragastrically administrated with O-glycosylation inhibitor (benzyl-α-GalNAc) at doses of 1 and 5 mg/kg, respectively, while control mice were administrated with the same volume of saline. Before and after administration of Con A for 6 and 12 h, mice were sacrificed and their plasma and livers were collected to score liver injury. Peripheral blood, spleen, and thymus were collected for flow cytometry analysis. The expression levels of neutrophilic alkaline phosphatase-3 (NALP3) and NALP6 in liver were evaluated as well.

RESULTS

Pre-treatment with benzyl-α-GalNAc increased the serum transaminase levels and induced more infiltration and necrosis in livers of Con A administrated mice. The levels of some pro-inflammation cytokines also increased in administrated mice. In addition, pretreatment with benzyl-α-GalNAc up-regulated the expression levels of NALP3 and NALP6. And benzyl-α-GalNAc inhibited the levels of apoptosis of thymus cells and influenced activation of T cells in peripheral blood and spleen of Con A administrated mice, especially that accelerated the physiological progression of CD4⁺CD25^-CD69⁺ subset.

CONCLUSION

The present research demonstrated that benzyl-α-GalNAc aggravated Con A-induced AIH, and the role of the O-glycosylation inhibitor as the aggravation may be related to regulation of the levels of cytokines, as well as influencing proliferation of T cells.

The role of the microbiota in acute stress-induced myeloid immune cell trafficking

There has been a growing recognition of the involvement of the gastrointestinal microbiota in the development of stress-related disorders. Acute stress leads to activation of neuroendocrine systems, which in turn orchestrate a large-scale redistribution of innate immune cells. Both these response systems are independently known to be primed by the microbiota, even though much is still unclear about the role of the gastrointestinal microbiota in acute stress-induced immune activation. In this study, we investigated whether the microbiota influences acute stress-induced changes in innate immunity using conventionally colonised mice, mice devoid of any microbiota (i.e. germ-free, GF), and colonised GF mice (CGF). We also explored the kinetics of stress-induced immune cell mobilisation in the blood, the spleen and mesenteric lymph nodes (MLNs). Mice were either euthanised prior to stress or underwent restraint stress and were then euthanised at various time points (i.e. 0, 45- and 240-minutes) post-stress. Plasma adrenaline and noradrenaline levels were analysed using ELISA and immune cell levels were quantified using flow cytometry. GF mice had increased baseline levels of adrenaline and noradrenaline, of which adrenaline was normalised in CGF mice. In tandem, GF mice had decreased circulating levels of LY6C^hi and LY6C^mid, CCR2+ monocytes, and granulocytes, but not LY6C-, CX3CR1+ monocytes. These deficits were normalised in CGF mice. Acute stress decreased blood LY6C^hi and LY6C^mid, CCR2+ monocytes while increasing granulocyte levels in all groups 45 min post-stress. However, only GF mice showed stress-induced changes in LY6C^hi monocytes and granulocytes 240 min post-stress, indicating impairments in the recovery from acute stress-induced changes in levels of specific innate immune cell types. LY6C-, CX3CR1+ monocytes remained unaffected by stress, indicating that acute stress impacts systemic innate immunity in a cell-type-specific manner. Overall, these data reveal novel cell-type-specific changes in the innate immune system in response to acute stress, which in turn are impacted by the microbiota. In conclusion, the microbiota influences the priming and recovery of the innate immune system to an acute stressor and may inform future microbiota-targeted therapeutics aimed at modulating stress-induced immune activation in stress-related disorders.

Suppression of the innate cancer-killing activity in human granulocytes by stress reaction as a possible mechanism for affecting cancer development

Psychological stress may be linked to cancer incidence; however, more direct evidence is required to support this viewpoint. In this study, we investigated the effects of stress on immunosurveillance against cancer cells using a previously established examination stress model. We showed that the cancer killing activity (CKA) of granulocytes (also known as polymorphic nuclear cells, PMNs) is sharply reduced during examination stress stimulation in some donors who are psychologically sensitive to examination stress, with the concentration of plasma stress hormones (cortisone, epinephrine, and norepinephrine) increasing accordingly. The effects of stress hormones on immune cell CKA were also investigated under two in vitro co-incubation conditions, with all three hormones found to exert inhibitory effects on the CKA of PMNs and mononuclear cells. We showed that stress triggered the release of stress hormones which had profound inhibitory effects on the innate anticancer functions of PMNs. These results provide a possible explanation for the relationship between psychological stress and cancer incidence.

Early-Life Adversity, Systemic Inflammation and Comorbid Physical and Psychiatric Illnesses of Adult Life

Recently, the evidence of increased immune activation in patients with schizophrenia has suggested a role for the immune system in the development of psychosis. However, what is causing this increased immune activation and how this leads to the development of psychopathology remain still unclear. In this chapter we discuss the evidence about the role of childhood trauma as possible underlying cause of the increased immune activation in patients with schizophrenia. According to preclinical and clinical models, early adverse events can disrupt the homeostatic control of immune responses and lead to enduring inflammatory dysregulation at a peripheral and central level. In fact, persisting systemic inflammation may facilitate peripheral tissues damage and breach the blood-brain barrier, leading to microglia activation and to neuroinflammation.Such chronic immune dysregulation also appear to partially explain the frequent comorbidity between psychosis and metabolic abnormalities, which have previously mainly considered as side effect of antipsychotic treatment.Overall, this evidence suggests that early stress may contribute to development of schizophrenia spectrum disorders through a modulation of the peripheral and central immune system and support the immune pathways as possible future therapeutic approach for psychosis.

Immune response to stress induction as a predictor of cognitive-behavioral therapy outcomes in adolescent mood disorders: A pilot study

Cognitive-behavioral therapy (CBT) alleviates symptoms of depression in youth with bipolar disorder (BD) and major depressive disorder (MDD). Empirical research has linked inflammatory markers to depressive symptoms and acute psychosocial stress; however, a gap remains as to whether immune response to stress may serve as a putative mechanism of treatment. This preliminary pilot study determined the modest feasibility of assessing psychobiological response to stress as a predictor of CBT outcomes for youth with mood disorders. We evaluated whether participation in a 10-session group-CBT intervention for mood disorders altered inflammatory response to a laboratory psychosocial stress induction and if this alteration in immune stress responsivity was related to a decrease in depressive symptoms. Thirty-four youth (age M = 15.03, SD = 1.91) diagnosed with BD or MDD participated in a 10-session CBT group and pre- and post-group assessments; twenty-eight participants who completed the group had usable cytokine data. Pre- and post-group assessments included stress induction with the Trier Social Stress Test (TSST) during which inflammatory cytokines were measured at baseline (time 0) and after the TSST at 30, 60, and 90 min. Results suggest it is modestly feasible to measure immune response to stress alongside CBT treatment for adolescent mood disorders. Our findings were mixed; across seven cytokines, hierarchical linear models indicated two cytokines, IL6 and IL12, were sensitive to acute laboratory stress. We also found significant correlations between life stress, inflammation, and depression both pre- and post- CBT group. Inflammation pre-group, as measured by IL12 and IL1 β predicted depressive symptoms following treatment. Although we did not find significant within-subject reductions in inflammation, chronic stress predicted changes in IL β, signaling the central role of chronic stress. This study offers preliminary evidence that immune responsivity to stress induction could serve as a mechanism of treatment for mood disorders in youth, indicating a potential marker for more personalized model of healthcare.

Contrasting Responses of Lizards to Divergent Ecological Stressors Across Biological Levels of Organization

It is frequently hypothesized that animals employ a generalized "stress response," largely mediated by glucocorticoid (GC) hormones, such as corticosterone, to combat challenging environmental conditions. Under this hypothesis, diverse stressors are predicted to have concordant effects across biological levels of an organism. We tested the generalized stress response hypothesis in two complementary experiments with juvenile and adult male Eastern fence lizards (Sceloporus undulatus). In both experiments, animals were exposed to diverse, ecologically-relevant, acute stressors (high temperature or red imported fire ants, Solenopsis invicta) and we examined their responses at three biological levels: behavioral; physiological (endocrine [plasma corticosterone and blood glucose concentrations] and innate immunity [complement and natural antibodies]); and cellular responses (gene expression of a panel of five heat-shock proteins in blood and liver) at 30 or 90 min post stress initiation. In both experiments, we observed large differences in the cellular response to the two stressors, which contrasts the similar behavioral and endocrine responses. In the adult experiment for which we had innate immune data, the stressors affected immune function independently, and they were correlated with CORT in opposing directions. Taken together, these results challenge the concept of a generalized stress response. Rather, the stress response was context specific, especially at the cellular level. Such context-specificity might explain why attempts to link GC hormones with life history and fitness have proved difficult. Our results emphasize the need for indicators at multiple biological levels and whole-organism examinations of stress.

Social Stress Mobilizes Hematopoietic Stem Cells to Establish Persistent Splenic Myelopoiesis

Psychosocial stress accelerates myelopoietic production of monocytes and neutrophils that contributes to a variety of health complications ranging from atherosclerosis to anxiety. Here, we show that social stress in mice mobilizes hematopoietic stem progenitor cells (HSPCs) from the bone marrow that enter circulation, engraft into the spleen, and establish a persistent extramedullary hematopoietic depot. These splenic progenitors actively proliferate and differentiate into multiple cell types, including monocytes, neutrophils, and erythrocytes. Splenic erythropoiesis partially abrogates stress-induced anemia. Repeated injection with isoprenaline induces progenitor mobilization to the spleen, identifying a key role for β-adrenergic signaling. Moreover, protracted splenic production of CD11b⁺ cells persists for at least 24 days after the cessation of social stress. Thus, chronic stress establishes a persistent extramedullary hematopoietic depot that can modify a wide range of chronic disease processes and alter homeostasis of the bi-directional regulatory axis between the nervous and immune systems.

Preemptive Anti-Stress Response Effects of Oxycodone Versus Sufentanil for Patients Undergoing Cardiac Valve Replacement-A Randomized Controlled Trial

Patients undergoing cardiac valve replacement may experience cardiovascular adverse events during the preoperative period before anesthesia. The study was to compare the preemptive anti-stress response effects of oxycodone versus sufentanil for patients undergoing cardiac valve replacement. Ninety-four patients were enrolled and assigned to group Oxy, group Suf and group NS. Patients in group Oxy were administrated with oxycodone 0.1 mg/kg, group Suf received sufentanil 0.1 μg/kg and group NS were given equivalent volume of normal saline. The primary outcomes included serum levels of cortisol, norepinephrine, and adrenaline. The secondary outcomes involved bispectral index value and the observer's assessment of awareness/sedation grade, levels of mean arterial pressure, heart rate, and the adverse reactions. Compared to group NS, the serum levels of cortisol at T₁ to T₅ (P < .05), and levels of norepinephrine and adrenaline at T₃ to T₅ (P < .05) in group Oxy and Suf were lower. The bispectral index value and observer's assessment of awareness/sedation grade T₁ to T₂ (P < .05) in group Suf were lower than those in group Oxy and NS. Compared with group NS, the levels of mean arterial pressure and heart rate in group Oxy and Suf at T₃ to T₅ (P < .05) were lower. The incidence of coughing was significantly higher in group Suf (23.3%), but not in group NS (6.7%), than that in group Oxy (3.3%). The preemptive analgesia of oxycodone may be used to inhibit the stress response, without leading to excessive sedation and respiratory depression, which may also help to stabilize hemodynamics during preoperative period.

Exacerbation of ozone-induced pulmonary and systemic effects by β2-adrenergic and/or glucocorticoid receptor agonist/s

Agonists of β₂ adrenergic receptors (β₂AR) and glucocorticoid receptors (GR) are prescribed to treat pulmonary diseases. Since ozone effects are mediated through the activation of AR and GR, we hypothesized that the treatment of rats with relevant therapeutic doses of long acting β₂AR agonist (LABA; clenbuterol; CLEN) and/or GR agonist (dexamethasone; DEX) would exacerbate ozone-induced pulmonary and systemic changes. In the first study, male 12-week-old Wistar-Kyoto rats were injected intraperitoneally with vehicle (saline), CLEN (0.004 or 0.02 mg/kg), or DEX (0.02 or 0.1 mg/kg). Since dual therapy is commonly used, in the second study, rats received either saline or combined CLEN + DEX (each at 0.005 or 0.02 mg/kg) one day prior to and on both days of exposure (air or 0.8ppm ozone, 4 hr/day x 2-days). In air-exposed rats CLEN, DEX or CLEN + DEX did not induce lung injury or inflammation, however DEX and CLEN + DEX decreased circulating lymphocytes, spleen and thymus weights, increased free fatty acids (FFA) and produced hyperglycemia and glucose intolerance. Ozone exposure of vehicle-treated rats increased bronchoalveolar lavage fluid protein, albumin, neutrophils, IL-6 and TNF-α. Ozone decreased circulating lymphocytes, increased FFA, and induced hypeerglycemia  and glucose intolerance. Drug treatment did not reverse ozone-induced ventillatory changes, however, lung effects (protein and albumin leakage, inflammation, and IL-6 increase) were exacerbated by CLEN and CLEN + DEX pre-treatment in a dose-dependent manner (CLEN > CLEN + DEX). Systemic effects induced by DEX and CLEN + DEX but not CLEN in air-exposed rats were analogous to and more pronounced than those induced by ozone. These data suggest that adverse air pollution effects might be exacerbated in people receiving LABA or LABA plus glucocorticoids.

Association Between Noninfectious Uveitis and Psychological Stress

Importance

Uveitis involves dysregulation of the ocular immune system. Stress has been shown to affect immune function, but it is unclear whether there is an association between stress and uveitis.

Objective

To determine whether having uveitis is associated with psychological stress.

Design, Setting, and Participants

A cross-sectional, case-control study including a self-administered survey, medical records review, and diurnal salivary cortisol test was conducted at a university-based uveitis clinic and comprehensive eye clinic. Participants included 146 consecutive adults with noninfectious uveitis and age-matched controls with no eye disease. The study was conducted from December 1, 2017, to March 14, 2018.

Main Outcomes and Measures

Participants completed the self-administered, Cohen 10-item Perceived Stress Scale (PSS-10), a demographics questionnaire. Responses to each question were categorized on a 5-point Likert scale, with total scores ranging from 0 (no stress) to 40 (high stress). In addition, participants submitted 3 salivary cortisol samples. Those with uveitis were classified as having recently active or controlled disease through medical records review. The prespecified primary analysis was a linear regression of PSS-10 score and uveitis correcting for age, sex, educational level, employment, and median income. Secondary analyses included comparing PSS-10 scores in patients with recently active and controlled uveitis, determining predictors of stress, and comparing diurnal salivary cortisol between uveitis and control groups.

Results

Of 146 eligible patients, 17 declined participation and 9 consented but were excluded because they did not complete both questionnaires, resulting in 120 patients (80 uveitis; 40 controls) in the final analysis. Eighty participants (66.7%) were women, and 70 (58.3%) were white. Median age was 40 years (interquartile range, 29-59 years). Having uveitis was associated with a 4.3-point increase in PSS-10 score (95% CI, 1.8 to 6.9; P = .002). There was no significant difference in PSS-10 scores between patients with recently active and controlled uveitis (1.0 point greater for patients with active uveitis; 95% CI, -2.0 to 3.9; P = .52). Factors associated with increased PSS-10 score in patients with uveitis included female sex (coefficient, 4.0; 95% CI, 1.6 to 6.5; P = .002), current immunomodulatory therapy (coefficient, 2.5; 95% CI, -0.3 to 5.2; P = .08), history of depression (coefficient, 3.8; 95% CI, 0.8 to 6.8; P = .02), and having posterior or panuveitis (coefficient, 2.6; 95% CI, 0.8 to 4.4; P = .006). Of the 70 participants (58.3%) who had testable samples for cortisol analysis, diurnal salivary cortisol levels did not significantly differ between uveitis and nonuveitis groups.

Conclusions and Relevance

These findings suggest that patients with uveitis have higher levels of psychological stress compared with controls, yet no significant difference was identified in the stress of patients with active vs controlled uveitis. Consequently, comprehensive treatment for noninfectious uveitis may be able to address the psychological results of this disease.

Beta-2 Adrenergic and Glucocorticoid Receptor Agonists Modulate Ozone-Induced Pulmonary Protein Leakage and Inflammation in Healthy and Adrenalectomized Rats

We have shown that acute ozone inhalation activates sympathetic-adrenal-medullary and hypothalamus-pituitary-adrenal stress axes, and adrenalectomy (AD) inhibits ozone-induced lung injury and inflammation. Therefore, we hypothesized that stress hormone receptor agonists (β2 adrenergic-β2AR and glucocorticoid-GR) will restore the ozone injury phenotype in AD, while exacerbating effects in sham-surgery (SH) rats. Male Wistar Kyoto rats that underwent SH or AD were treated with vehicles (saline + corn oil) or β2AR agonist clenbuterol (CLEN, 0.2 mg/kg, i.p.) + GR agonist dexamethasone (DEX, 2 mg/kg, s.c.) for 1 day and immediately prior to each day of exposure to filtered air or ozone (0.8 ppm, 4 h/day for 1 or 2 days). Ozone-induced increases in PenH and peak-expiratory flow were exacerbated in CLEN+DEX-treated SH and AD rats. CLEN+DEX affected breath waveform in all rats. Ozone exposure in vehicle-treated SH rats increased bronchoalveolar lavage fluid (BALF) protein, N-acetyl glucosaminidase activity (macrophage activation), neutrophils, and lung cytokine expression while reducing circulating lymphocyte subpopulations. AD reduced these ozone effects in vehicle-treated rats. At the doses used herein, CLEN+DEX treatment reversed the protection offered by AD and exacerbated most ozone-induced lung effects while diminishing circulating lymphocytes. CLEN+DEX in air-exposed SH rats also induced marked protein leakage and reduced circulating lymphocytes but did not increase BALF neutrophils. In conclusion, circulating stress hormones and their receptors mediate ozone-induced vascular leakage and inflammatory cell trafficking to the lung. Those receiving β2AR and GR agonists for chronic pulmonary diseases, or with increased circulating stress hormones due to psychosocial stresses, might have altered sensitivity to air pollution.

The Practical Use of White Cell Inflammatory Biomarkers in Prediction of Postoperative Delirium after Cardiac Surgery

: Introduction: Postoperative delirium (POD) is associated with unfavorable outcomes. It may result from neuroinflammation and oxidative stress. The aim of this study was to evaluate the role of routinely available inflammatory markers derived from white blood cell count (WBC), for prognostic value in diagnosing delirium after cardiac surgery.

METHODS

We performed an analysis of data collected from patients undergoing planned coronary artery bypass grafting (CABG). Differential WBC and CRP concentration were evaluated preoperatively (T0) and postoperatively at day 1 (T1), 3 (T3), 5 (T5) after CABG. Differences in neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and platelet-to-WBC ratio (PWR) between patients with (Del+) and without delirium (Del-) were evaluated. Patients were screened using CAM-ICU.

RESULTS

We included 968 patients in the study. Incidence of delirium was 13.3%. In the group with POD, the majority of patients were men (87/129, 67.44%), and the mean age was 72 years. Preoperative WBC (8.21 ± 3.04 G/l vs. 7.55 ± 1.86 G/l, p = 0.029) were higher and mean platelet count was lower (217.7 ± 69.07 G/l vs. 227.44 ± 59.31 G/l, p = 0.031) in patients with POD. Lower pre-operative PLR values (109.87 ± 46.38 vs. 120.36 ± 52.98, p = 0.026) and PWR values (27.69 7.50 vs. 31.32 9.88 p < 0.001) were found in patients with POD. Association was strongest for PWR and remained significant at T1 (p < 0.001), T3 (p < 0.001) and T5 (p < 0.001). Basing on coefficients of logistic regression a model for optimal prediction of POD was calculated: CARDEL Index = 0.108 × Age + 0.341 × HBA1C - 0.049 × PWR with AUC of 0.742 (p < 0.001).

CONCLUSIONS

The results of this study show that lower pre-operative levels of PLR and PWR were associated with POD after cardiac surgery. Pre-operative PWR showed strongest correlation with POD and may be a potential new biomarker associated with postoperative delirium. CARDEL prognosis index composed of age, HbA1c and PWR is good at predicting development of delirium after CABG.

Association between chronotype and body mass index: The role of C-reactive protein and the cortisol response to stress

BACKGROUND

Chronotype influences several physiological systems, including the immune system and the hypothalamus-pituitary-adrenal (HPA)-axis. Previous research has shown that evening chronotype is associated with adverse metabolic health outcomes and obesity. However, the exact mechanisms underlying the observed differences in metabolic function between "morning" and "evening" types remain to be explored.

OBJECTIVE

To investigate the relationship of chronotype with inflammatory and neuroendocrine stress markers and to explore their mediating and moderating roles in the association between chronotype and body mass index (BMI).

METHODS

Twenty-eight healthy young adults (50% women), mean age 23.8 ± 3.3 (SD) years, underwent a standardized laboratory stress test (Trier Social Stress Test, TSST). Concentrations of plasma C-reactive protein (CRP) at baseline and of salivary cortisol before and after the onset of the stressor were analyzed. Heart rate was measured continuously. Chronotype was assessed with the Morningness-Eveningness Questionnaire (MEQ).

RESULTS

Lower MEQ scores (i.e. evening tendency) were associated with higher BMI (r = -.40, p < .05), elevated CRP concentrations (r = -.42, p < .05) and higher cortisol responses to acute stress (r = -.53, p < .01). The relationship between MEQ score and BMI was mediated by CRP concentrations (b = -0.03, CI 95%: -0.08 to -0.007, p < .05). In addition, we observed a moderating effect of the cortisol stress response on this mediated relationship (b = 0.005, CI 95%: 0.0002 to 0.01, p < .05), such that the mediated relationship was stronger in individuals with a higher cortisol response.

CONCLUSION

Enhanced pro-inflammatory state and a higher cortisol response to stress may underlie the effect of evening chronotype on obesity risk and adverse metabolic health outcomes.

Effects of Transportation and Relocation on Immunologic Measures in Cynomolgus Macaques (Macaca fascicularis)

NHP are a small, but critical, portion of the animals studied in research laboratories. Many NHP are imported or raised at one facility and subsequently moved to another facility for research purposes. To improve our understanding of the effects of transportation and relocation on the NHP immune system, to minimize potential confounds associated with relocation, and to maximize study validity, we examined the phenotype and function of PBMC in cynomolgus macaques (Macaca fascicularis) that were transported approximately 200 miles by road from one facility to another. We evaluated the phenotype of lymphocyte subsets through flow cytometry, mitogen-specific immune responses of PBMC in vitro, and plasma levels of circulating cytokines before transportation, at approximately 24 h after arrival (day 2), and after 30 d of acclimation. Analyses of blood samples revealed that the CD3+ and CD4+ T-cell counts increased significantly, whereas NK+, NKT, and CD14+ CD16+ nonclassical monocyte subsets were decreased significantly on day 2 after relocation compared with baseline. We also noted significantly increased immune cell function as indicated by mitogen-specific proliferative responses and by IFNγ levels on day 2 compared with baseline. After 30 d of acclimation, peripheral blood CD4+ T-cells and monocyte counts were higher than baseline, whereas B-cell numbers were lower. The mitogen-induced responses to LPS and IFNγ production after stimulation with pokeweed mitogen or phytohemagglutinin remained significantly different from baseline. In conclusion, the effects of transportation and relocation on immune parameters in cynomolgus monkeys are significant and do not fully return to baseline values even after 30 d of acclimation.

Neuroendocrine Regulation of Tumor-Associated Immune Cells

Mounting preclinical and clinical evidence continues to support a role for the neuroendocrine system in the modulation of tumor biology and progression. Several studies have shown data supporting a link between chronic stress and cancer progression. Dysregulation of the sympathetic nervous system (SNS) and the hypothalamic-pituitary-adrenal (HPA) axis has been implicated in promoting angiogenesis, tumor cell proliferation and survival, alteration of the immune response and exacerbating inflammatory networks in the tumor microenvironment. Here, we review how SNS and HPA dysregulation contributes to disturbances in immune cell populations, modifies cancer biology, and impacts immunotherapy response. We also highlight several interventions aimed at circumventing the adverse effects stress has on cancer patients.

Characteristics, Risk Factors And Outcome Of Early-Onset Delirium In Elderly Patients With First Ever Acute Ischemic Stroke - A Prospective Observational Cohort Study

Introduction

Post-stroke delirium is a common clinical problem, occurring in 10% to 48% of patients. It has been associated with longer hospitalization times, increased mortality and worse functional outcome. In early phase of stroke, it may be regarded as particularly difficult to differentiate from other neurological symptoms. For practical purposes, there is a need to identify simple pre-operative laboratory parameters that may aid delirium diagnosis early after stroke. Our aim was to identify the incidence of early-onset (first 24 hrs) post-stroke delirium, its risk factors and outcomes (complications and mortality) in patients with first-ever acute ischemic stroke (AIS).

Material and methods

A retrospective analysis of a prospective observational study (NCT03944694) was performed. Patients were screened for delirium using CAM-ICU method. Clinical and laboratory data were collected, including baseline inflammatory parameters.

Results

Final analysis included 760 patients, 121 (15.9%) developed delirium. Patients with delirium were older (75.9±13.5 years, p<0.001). Most common complications in the delirium group were pulmonary (57.8% vs 21.4%, p<0.001), cardiac (38.8% vs 13.6%, p<0.001) and renal (13.2% vs 7.5%, p=0.038). Neutrophil-to-lymphocyte ratio (NLR) (6.71±9.65 vs 4.55±5.51, p<0.001), C-reactive protein level (32.59±65.94 vs 15.70±38.56, p<0.001) and troponin T level (72.59±180.15 vs 26.85±77.62, p<0.001) were higher in delirious patients and platelet-to white blood cell count ratio (PWR) (23.42±9.51 vs 27.13±10.58, p<0.001) was lower. Multivariable logistic regression showed that atrial fibrillation (OR 1.651, p=0.049), higher Rankin score on admission (OR 1.689, p<0.001), hemianopia (OR 2.422, p=0.003) and PWR <20.22 (OR 2.197, p=0.002) were independently associated with delirium. Kaplan–Meier curves indicated that mortality increased for patients with delirium at 3 months (p<0.001) and 1 year (p<0.001) after AIS.

Conclusion

Atrial fibrillation, higher Rankin score, hemianopia and lower PWR were independently associated with early onset delirium in patients with first ever AIS. This confirms that deprivation of senses and early generalized inflammatory response are critical for delirium development.

Exercise training, circulating cytokine levels and immune function in cancer survivors: A meta-analysis

BACKGROUND

Anti-cancer therapies lead to chronic non-resolving inflammation and reduced immune function. One potential therapy is exercise training, but the effectiveness of these interventions to improve immune-related outcomes, the gaps in the literature, and recommendations to progress the field need to be determined.

OBJECTIVES

(1) to conduct separate meta-analyses in cancer survivors to determine the effects of exercise training on pro- and anti-inflammatory markers, and immune cell proportions and function; and (2) to perform subgroup analyses to determine whether exercise modality, cancer type, and specific markers help to explain heterogeneity in each meta-analysis.

DATA SOURCES

Electronic databases (PubMed/MEDLINE, EMBASE, CENTRAL, and CINAHL) from inception to March 2018. The reference lists of eligible articles and relevant reviews were also checked.

STUDY SELECTION

Inclusion criteria were adult cancer survivors from randomized controlled trials performing structured exercise intervention (aerobic, resistance or combined training or Tai Chi/yoga) compared to usual care control group and included pro-inflammatory, anti-inflammatory, and/or immune cell outcomes.

APPRAISAL AND SYNTHESIS METHODS

A total of 5349 potentially eligible articles were identified, of which 26 articles (27 trials) met the inclusion criteria. Effect sizes were calculated as standardized mean differences (SMD), where <0.2 was defined as trivial, 0.2-0.3 as small, 0.4-0.8 as moderate, and >0.8 as a large effect.

RESULTS

Exercise training decreased pro-inflammatory markers (SMD: -0.2, 95% CI: -0.4, -0.1, p < 0.001). Sub-group analysis for the pro-inflammatory markers indicated that combined aerobic and resistance training had the greatest effect (SMD: -0.3, 95% CI: -0.5, -1.9, p < 0.001), that prostate (SMD: -0.5, 95% CI: -0.8, 0.1, p = 0.004) and breast cancer populations were most responsive (SMD: -0.2, 95% CI: -0.3, -0.1, p = 0.001), and that C-reactive protein (SMD: -0.5, 95% CI: -0.9, -0.06, p = 0.025) and tumor necrosis factor (SMD: -0.3, 95% CI: -0.5, -0.06, p = 0.004) were the most sensitive to change. Exercise training tended to decrease anti-inflammatory markers (p = 0.072) but had no effect on natural killer or natural killer T cell proportions or cytotoxic activity.

CONCLUSIONS

Exercise training reduces pro-inflammatory markers in cancer survivors, with the strongest evidence for combined training and for prostate and breast cancer survivors. Further research is warranted to determine if these changes are clinically relevant or are associated with improvements in symptoms. To strengthen future research, focusing on novel immune populations that include functional parameters and standardized reporting of key immune outcomes is recommended.

Monocyte mobilisation, microbiota & mental illness

The gastrointestinal microbiome has emerged as a key player in regulating brain and behaviour. This has led to the strategy of targeting the gut microbiota to ameliorate disorders of the central nervous system. Understanding the underlying signalling pathways in which the microbiota impacts these disorders is crucial for the development of future therapeutics for improving CNS functionality. One of the major pathways through which the microbiota influences the brain is the immune system, where there is an increasing appreciation for the role of monocyte trafficking in regulating brain homeostasis. In this review, we will shed light on the role of monocyte trafficking as a relay of microbiota signals in conditions where the central nervous system is in disorder, such as stress, peripheral inflammation, ageing, traumatic brain injury, stroke, multiple sclerosis, Alzheimer's disease and Parkinson's disease. We also cover how the gastrointestinal microbiota is implicated in these mental illnesses. In addition, we aim to discuss how the monocyte system can be modulated by the gut microbiota to mitigate disorders of the central nervous system, which will lead to novel microbiota-targeted strategies.

Activation of the kynurenine pathway and mitochondrial respiration to face allostatic load in a double-hit model of stress

Allostasis is the process by which the body's physiological systems adapt to environmental changes. Chronic stress increases the allostatic load to the body, producing wear and tear that could, over time, become pathological. In this study, young adult male Wistar Kyoto rats were exposed to an unpredictable chronic mild stress (uCMS) protocol to increase allostatic load. First, physiological systems which may be affected by extended uCMS exposure were assessed. Secondly, 5 weeks of uCMS were used to investigate early adaptations in the previously selected systems. Adverse experiences during developmentally sensitive periods like adolescence are known to severely alter the individual stress vulnerability with long-lasting effects. To elucidate how early life adversity impacts stress reactivity in adulthood, an additional group with juvenile single-housing (JSH) prior to uCMS was included in the second cohort. The aim of this work was to assess the impact of chronic stress with or without adversity during adolescence on two domains known to be impacted in numerous stress-related disorders: mitochondrial energy metabolism and the immune system. Both, uCMS and adolescence stress increased kynurenine and kynurenic acid in plasma, suggesting a protective, anti-oxidant response from the kynurenine pathway. Furthermore, uCMS resulted in a down-regulation of immediate early gene expression in the prefrontal cortex and hippocampus, while only rats with the double-hit of adolescent stress and uCMS demonstrated increased mitochondrial activity in the hippocampus. These results suggest that early life adversity may impact on allostatic load by increasing energetic requirements in the brain.

The good side of "stress"

Stress has both a good and bad side which are discussed in terms of the concepts of allostasis and allostatic load and overload. Stressful experiences can cause health damaging behaviors which lead to allostatic load and overload and accelerate disease processes.

Glucocorticoids mediate stress induction of the alarmin HMGB1 and reduction of the microglia checkpoint receptor CD200R1 in limbic brain structures

Exposure to stressors primes neuroinflammatory responses to subsequent immune challenges and stress-induced glucocorticoids (GCs) play a mediating role in this phenomenon of neuroinflammatory priming. Recent evidence also suggests that the alarmin high-mobility group box-1 (HMGB1) and the microglial checkpoint receptor CD200R1 serve as proximal mechanisms of stress-induced neuroinflammatory priming. However, it is unclear whether stress-induced GCs play a causal role in these proximal mechanisms of neuroinflammatory priming; this forms the focus of the present investigation. Here, we found that exposure to a severe acute stressor (inescapable tailshock) induced HMGB1 and reduced CD200R1 expression in limbic brain regions and pharmacological blockade of GC signaling (RU486) mitigated these effects of stress. To confirm these effects of RU486, adrenalectomy (ADX) with basal corticosterone (CORT) replacement was used to block the stress-induced increase in GCs as well as effects on HMGB1 and CD200R1. As with RU486, ADX mitigated the effects of stress on HMGB1 and CD200R1. Subsequently, exogenous CORT was administered to determine whether GCs are sufficient to recapitulate the effects of stress. Indeed, exogenous CORT induced expression of HMGB1 and reduced expression of CD200R1. In addition, exposure of primary microglia to CORT also recapitulated the effects of stress on CD200R1 suggesting that CORT acts directly on microglia to reduce expression of CD200R1. Taken together, these findings suggest that GCs mediate the effects of stress on these proximal mechanisms of neuroinflammatory priming.