Raised cortisol:DHEAS ratios in the elderly after injury: potential impact upon neutrophil function and immunity

The rates of septicemia in older adults with prostate cancer treated with abiraterone or enzalutamide: A population-based study

INTRODUCTION

Prostate cancer (PCa) is the most common non-cutaneous tumor among American men. Androgen receptor signaling inhibitors such as abiraterone and enzalutamide have been approved for similar disease states among patients with advanced PCa. Existing data suggest using steroids is associated with an increased risk of infection. Because abiraterone is usually prescribed with prednisone, we sought to compare the risk of septicemia in patients using abiraterone vs. enzalutamide.

MATERIALS AND METHODS

We utilized the SEER-Medicare-linked data and used negative binomial regression models to compare the changes in the rates of septicemia-related hospitalizations six months pre- and post-abiraterone and enzalutamide initiation.

RESULTS

We found that the incidence of septicemia-related hospitalizations increased 2.77 fold within six months of initiating abiraterone (incidence rate ratio [IRR]: 2.77, 95% confidence interval [CI]: 2.17-3.53) 1.97 fold within six months of starting enzalutamide (IRR: 1.97, 95% CI: 1.43-2.72). However, the difference in the changes did not reach statistical significance (interaction IRR: 0.71, 95% CI: 0.48-1.06).

DISCUSSION

The findings suggest that both abiraterone and enzalutamide are associated with an increased risk of septicemia-related hospitalizations. However, the difference in the increase of septicemia risk following the two treatments did not reach statistical significance. Further studies are warranted to understand the mechanisms at play.

DHEA and response to antidepressant treatment: A Mendelian Randomization analysis

Treatment response is hard to predict and detailed mechanisms unknown. Lower levels of the dehydroepiandrosterone sulphate (DHEA(S)) - a precursor to testosterone and estrogen - have been associated to depression and to response to antidepressant treatment. Previous studies however may have been ridden by confounding and reverse causation. The aim of this study is to evaluate whether higher levels of DHEA(S) are causally linked to response to antidepressants using mendelian randomization (MR). We performed a Two-sample MR analysis using data the largest publicly available GWAS of DHEA(S) levels (n = 14,846) using eight common genetic variants associated to DHEA(S) (seven single nucleotide polymorphisms and one variant rs2497306) and the largest GWAS of antidepressant response (n = 5218) using various MR methods (IVW, MR Egger, Weighted mean, weighted mode, MR-PRESSO) and single SNP analysis. We further investigated for pleiotropy conducting a look up on PhenoScanner and GWAS Catalog. Results show no evidence for DHEA(S) gene risk score from any of MR methods, however, we found a significant association on individual variant analysis for rs11761538, rs17277546, and rs2497306. There was some evidence for heterogeneity and pleiotropy. This is the first paper to show some evidence for a causal association of genetically-predicted DHEA and improvement of depressive symptoms. The effect is not a simple linear effect, and we were unable to dissect whether the effect was direct effect of DHEA(S), mediated by DHEA(S) or on the pathway is not yet clear. Further studies using more refined instrumental variables will help clarify this association.

Age-related Changes in the Adrenal Cortex: Insights and Implications

Aging is characterized by a gradual decline in physiological function. This process affects all organs including the adrenal cortex, which normally functions to produce essential steroid hormones including mineralocorticoids, glucocorticoids, and androgens. With increasing age, features such as reduced adrenal cortex size, altered zonation, and increased myeloid immune cell infiltration substantially alter the structure and function of the adrenal cortex. Many of these hallmark features of adrenal cortex aging occur both in males and females, yet are more enhanced in males. Hormonally, a substantial reduction in adrenal androgens is a key feature of aging, which is accompanied by modest changes in aldosterone and cortisol. These hormonal changes are associated with various pathological consequences including impaired immune responses, decreased bone health, and accelerated age-related diseases. One of the most notable changes with adrenal aging is the increased incidence of adrenal tumors, which is sex dimorphic with a higher prevalence in females. Increased adrenal tumorigenesis with age is likely driven by both an increase in genetic mutations as well as remodeling of the tissue microenvironment. Novel antiaging strategies offer a promising avenue to mitigate adrenal aging and alleviate age-associated pathologies, including adrenal tumors.

Counteracting Immunosenescence-Which Therapeutic Strategies Are Promising?

Aging attenuates the overall responsiveness of the immune system to eradicate pathogens. The increased production of pro-inflammatory cytokines by innate immune cells under basal conditions, termed inflammaging, contributes to impaired innate immune responsiveness towards pathogen-mediated stimulation and limits antigen-presenting activity. Adaptive immune responses are attenuated as well due to lowered numbers of naïve lymphocytes and their impaired responsiveness towards antigen-specific stimulation. Additionally, the numbers of immunoregulatory cell types, comprising regulatory T cells and myeloid-derived suppressor cells, that inhibit the activity of innate and adaptive immune cells are elevated. This review aims to summarize our knowledge on the cellular and molecular causes of immunosenescence while also taking into account senescence effects that constitute immune evasion mechanisms in the case of chronic viral infections and cancer. For tumor therapy numerous nanoformulated drugs have been developed to overcome poor solubility of compounds and to enable cell-directed delivery in order to restore immune functions, e.g., by addressing dysregulated signaling pathways. Further, nanovaccines which efficiently address antigen-presenting cells to mount sustained anti-tumor immune responses have been clinically evaluated. Further, senolytics that selectively deplete senescent cells are being tested in a number of clinical trials. Here we discuss the potential use of such drugs to improve anti-aging therapy.

Immunosenescence, Inflammaging, and Frailty: Role of Myeloid Cells in Age-Related Diseases

The immune system is the central regulator of tissue homeostasis, ensuring tissue regeneration and protection against both pathogens and the neoformation of cancer cells. Its proper functioning requires homeostatic properties, which are maintained by an adequate balance of myeloid and lymphoid responses. Aging progressively undermines this ability and compromises the correct activation of immune responses, as well as the resolution of the inflammatory response. A subclinical syndrome of "homeostatic frailty" appears as a distinctive trait of the elderly, which predisposes to immune debilitation and chronic low-grade inflammation (inflammaging), causing the uncontrolled development of chronic and degenerative diseases. The innate immune compartment, in particular, undergoes to a sequela of age-dependent functional alterations, encompassing steps of myeloid progenitor differentiation and altered responses to endogenous and exogenous threats. Here, we will review the age-dependent evolution of myeloid populations, as well as their impact on frailty and diseases of the elderly.

Immune modulation after traumatic brain injury

Traumatic brain injury (TBI) induces instant activation of innate immunity in brain tissue, followed by a systematization of the inflammatory response. The subsequent response, evolved to limit an overwhelming systemic inflammatory response and to induce healing, involves the autonomic nervous system, hormonal systems, and the regulation of immune cells. This physiological response induces an immunosuppression and tolerance state that promotes to the occurrence of secondary infections. This review describes the immunological consequences of TBI and highlights potential novel therapeutic approaches using immune modulation to restore homeostasis between the nervous system and innate immunity.

Advanced age is associated with changes in alveolar macrophages and their responses to the stress of traumatic injury

Alveolar macrophages (AMs) are tissue-resident cells of the lower airways that perform many homeostatic functions critical for pulmonary health and protection against pathogens. However, little is known about the factors that shape AMs during healthy aging. In these studies, we sought to characterize age-related changes in AM phenotype, function, and responses to a physiologic stressor, that is, distal injury. Age was associated with a wide range of changes in cell surface receptor and gene expression by AMs, reflecting a unique alternatively activated phenotype. AMs from aged mice also exhibited markers of cellular senescence along with down-regulation of genes involved in growth and cell cycle pathways relative to young controls. Furthermore, AMs from aged mice showed a stunted transcriptional response to distal injury compared with AMs from young mice. Many changes were found to involve glucocorticoid-regulated genes, and corticosteroid treatment of primary AMs ex vivo revealed diminished transcriptional responses in cells from aged animals. These results demonstrate that there is a complex age-dependent AM phenotype associated with dysregulated stress hormone signaling that may interfere with AM responses to physiologic stressors and could contribute to AM dysfunction and the decline of pulmonary immunity during healthy aging.

Physical Activity Influences Cortisol and Dehydroepiandrosterone (Sulfate) Levels in Older Adults: A Systematic Review and Meta-Analysis

Age-related changes affect the ratio between two steroid hormones of the hypothalamic-pituitary-adrenal axis, cortisol and dehydroepiandrosterone (sulfate) (DHEA[S]). Physical activity (PA) may buffer the effects of chronic stress and counteract the aging decline of DHEA(S). Therefore, a systematic review was conducted to understand how PA influences physiological markers of cortisol and/or DHEA(S) and whether there is a difference in observational associations or experimental effects in older adults aged 65 years and older. A narrative synthesis was performed on nine observational studies, and meta-analyses were performed on 22 randomized controlled trials. There was low- to moderate-quality evidence that regular PA beneficially reduces cortisol and increases DHEA(S) levels. Subgroup analyses showed no clinically important differences between men and women, different exercise modalities, or health states. The findings cautiously suggest that regular PA of older adults' own choice that they find enjoyable could be recommended to improve cortisol and/or DHEA(S) levels.

An integrated analysis and comparison of serum, saliva and sebum for COVID-19 metabolomics

The majority of metabolomics studies to date have utilised blood serum or plasma, biofluids that do not necessarily address the full range of patient pathologies. Here, correlations between serum metabolites, salivary metabolites and sebum lipids are studied for the first time. 83 COVID-19 positive and negative hospitalised participants provided blood serum alongside saliva and sebum samples for analysis by liquid chromatography mass spectrometry. Widespread alterations to serum-sebum lipid relationships were observed in COVID-19 positive participants versus negative controls. There was also a marked correlation between sebum lipids and the immunostimulatory hormone dehydroepiandrosterone sulphate in the COVID-19 positive cohort. The biofluids analysed herein were also compared in terms of their ability to differentiate COVID-19 positive participants from controls; serum performed best by multivariate analysis (sensitivity and specificity of 0.97), with the dominant changes in triglyceride and bile acid levels, concordant with other studies identifying dyslipidemia as a hallmark of COVID-19 infection. Sebum performed well (sensitivity 0.92; specificity 0.84), with saliva performing worst (sensitivity 0.78; specificity 0.83). These findings show that alterations to skin lipid profiles coincide with dyslipidaemia in serum. The work also signposts the potential for integrated biofluid analyses to provide insight into the whole-body atlas of pathophysiological conditions.

Case report: Catheter related blood stream infection caused by Candida vulturna

Candida vulturna is a newly emerging candida species belong to Candida haemulonii species complex of Metschnikowiaceae family. Numerous clinical samples have been reported to isolate C. vulturna since discovery. We report a case of catheter related blood stream infection in which C. vulturna was isolated from blood in patient after prolong antibiotic therapy for recurrent infection of retroperitoneal cyst. The blood isolate was identified to species level by molecular assay targeting D1/D2 regions of 26s rDNA gene. The patient improved with administration of intravenous micafungin despite lack of antifungal susceptibility breakpoints.

Applying machine learning to explore the association between biological stress and near misses in emergency medicine residents

Physician stress is associated with near misses and adverse medical events. However, little is known about physiological mechanisms linking stress to such events. We explored the utility of machine learning to determine whether the catabolic stress hormone cortisol and the anabolic, anti-stress hormone dehydroepiandrosterone sulfate (DHEA-S), as well as the cortisol to DHEA-S ratio relate to near misses in emergency medicine residents during active duty in a trauma 1 emergency department. Compared to statistical models better suited for inference, machine learning models allow for prediction in situations that have not yet occurred, and thus better suited for clinical applications. This exploratory study used multiple machine learning models to determine possible relationships between biomarkers and near misses. Of the various models tested, support vector machine with radial bias function kernels and support vector machine with linear kernels performed the best, with training accuracies of 85% and 79% respectively. When evaluated on a test dataset, both models had prediction accuracies of around 80%. The pre-shift cortisol to DHEA-S ratio was shown to be the most important predictor in interpretable models tested. Results suggest that interventions that help emergency room physicians relax before they begin their shift could reduce risk of errors and improve patient and physician outcomes. This pilot demonstrates promising results regarding using machine learning to better understand the stress biology of near misses. Future studies should use larger groups and relate these variables to information in electronic medical records, such as objective and patient-reported quality measures.

Functions of dehydroepiandrosterone in relation to breast cancer

Although DHEA sulfate (DS) is the most abundant steroid in the circulation, breast fluid contains an approximately 80-fold greater concentration than serum. Transport of DS into cells requires organic anion transporting polypeptides (OATPs), which are specific for cell type, cell location, and substrate, but may have a broader specificity for housekeeping functions. Specific classes, which may be modified by soluble factors including neutral steroids, have been identified in the breast. After transport, DS may be cleaved to DHEA by ubiquitous sulfatases, which may be modified by the cell milieu, or DHEA may enter by diffusion. Synthesis from cholesterol does not occur because CYP17B12 and cytochrome b5 are lacking in breast tissues. Case-control studies reveal a positive association of serum DS with risk of breast cancer. The association is even greater with DHEA, particularly in postmenopausal women with HR + invasive tumors. Metabolites of DHEA, androstenedione and testosterone, are associated with breast cancer but DHEA is likely to have an independent role as well. Mechanisms by which DHEA may promote breast cancer relate to its effect in increasing circulating IGF-I, by inhibiting the suppressive effect of glucocorticoids, and by promoting retention of pre-adipocytes with aromatase activity. In addition, DHEA may interact with the G-protein coupled receptor GPER for stimulation of miR-21 and subsequent activation of the MAPK pathway. DHEA also has antitumor properties that relate to stimulation of immunity, suppression of inflammation, and elevation of adipose tissue adiponectin synthesis. The net effect may depend on the which factors predominate.

A prospective, phase II, single-centre, cross-sectional, randomised study investigating Dehydroepiandrosterone supplementation and its Profile in Trauma: ADaPT

INTRODUCTION

The improvements in short-term outcome after severe trauma achieved through early resuscitation and acute care can be offset over the following weeks by an acute systemic inflammatory response with immuneparesis leading to infection, multiorgan dysfunction/multiorgan failure (MOF) and death. Serum levels of the androgen precursor dehydroepiandrosterone (DHEA) and its sulfate ester DHEAS, steroids with immune-enhancing activity, are low after traumatic injury at a time when patients are catabolic and immunosuppressed. Addressing this deficit and restoring the DHEA(S) ratio to cortisol may provide a range of physiological benefits, including immune modulatory effects.

OBJECTIVE

Our primary objective is to establish a dose suitable for DHEA supplementation in patients after acute trauma to raise circulating DHEA levels to at least 15 nmol/L. Secondary objectives are to assess if DHEA supplementation has any effect on neutrophil function, metabolic and cytokine profiles and which route of administration (oral vs sublingual) is more effective in restoring circulating levels of DHEA, DHEAS and downstream androgens.

METHODS AND ANALYSIS

A prospective, phase II, single-centre, cross-sectional, randomised study investigating Dehydroepiandrosterone supplementation and its profile in trauma, with a planned recruitment between April 2019 and July 2021, that will investigate DHEA supplementation and its effect on serum DHEA, DHEAS and downstream androgens in trauma. A maximum of 270 patients will receive sublingual or oral DHEA at 50, 100 or 200 mg daily over 3 days. Females aged ≥50 years with neck of femur fracture and male and female major trauma patients, aged 16-50 years with an injury severity score ≥16, will be recruited.

ETHICS AND DISSEMINATION

This protocol was approved by the West Midlands - Coventry and Warwickshire Research Ethics Committee (Reference 18/WM/0102) on 8 June 2018. Results will be disseminated via peer-reviewed publications and presented at national and international conferences.

TRIAL REGISTRATION

This trial is registered with the European Medicines Agency (EudraCT: 2016-004250-15) and ISRCTN (12961998). It has also been adopted on the National Institute of Health Research portfolio (CPMS ID:38158).

TRIAL PROGRESSION

The study recruited its first patient on 2 April 2019 and held its first data monitoring committee on 8 November 2019. DHEA dosing has increased to 100 mg in both male cohorts and remains on 50 mg in across all female groups.

The Consequences of Aging On the Response to Injury and Critical Illness

Changing demographic trends have led to an increase in the overall geriatric trauma patient volume. Furthermore, the intersection of aging and injury can be problematic because geriatric patients have multiple comorbidities, geriatric-specific syndromes, and reduced physiological reserve. Despite mounting evidence that frail geriatric patients have inferior outcomes following trauma, very few studies have examined the effect of aging on the biological response to injury. In the present article, we review the current literature and explore the pathophysiological rationale underlying observed data, available evidence, and future directions on this topic.

An update in toxicology of ageing

The field of ageing research has been rapidly advancing in recent decades and it had provided insight into the complexity of ageing phenomenon. However, as the organism-environment interaction appears to significantly affect the organismal pace of ageing, the systematic approach for gerontogenic risk assessment of environmental factors has yet to be established. This puts demand on development of effective biomarker of ageing, as a relevant tool to quantify effects of gerontogenic exposures, contingent on multidisciplinary research approach. Here we review the current knowledge regarding the main endogenous gerontogenic pathways involved in acceleration of ageing through environmental exposures. These include inflammatory and oxidative stress-triggered processes, dysregulation of maintenance of cellular anabolism and catabolism and loss of protein homeostasis. The most effective biomarkers showing specificity and relevancy to ageing phenotypes are summarized, as well. The crucial part of this review was dedicated to the comprehensive overview of environmental gerontogens including various types of radiation, certain types of pesticides, heavy metals, drugs and addictive substances, unhealthy dietary patterns, and sedentary life as well as psychosocial stress. The reported effects in vitro and in vivo of both recognized and potential gerontogens are described with respect to the up-to-date knowledge in geroscience. Finally, hormetic and ageing decelerating effects of environmental factors are briefly discussed, as well.

Aging and Allostasis: Using Bayesian Network Analytics to Explore and Evaluate Allostatic Markers in the Context of Aging

Allostatic load reflects the cumulative strain on organic functions that may gradually evolve into overt disease. Our aim was to evaluate the allostatic parameters in the context of aging, and identify the parameters that may be suitable for an allostatic load index for elderly people (>60 years). From previously published studies, 11 allostatic (bio)markers could be identified that sustain sufficient variability with aging to capture meaningful changes in health status. Based on reported statistics (prevalence of a biomarker and its associated outcome, and/or an odds/risk ratio relating these two), seven of these could be adopted in a Bayesian Belief Network (BBN), providing the probability of “disturbed” allostasis in any given elder. Additional statistical analyses showed that changes in IL-6 and BMI contributed the most to a “disturbed” allostasis, indicating their prognostic potential in relation to deteriorating health in otherwise generally healthy elderly. In this way, and despite the natural decline in variance that irrevocably alters the prognostic relevance of most allostatic (bio)markers with aging, it appeared possible to outline an allostatic load index specifically for the elderly. The allostatic parameters here identified might consequently be considered a useful basis for future quantitative modelling in the context of (healthy) aging.

Endocrine-Disrupting Chemicals' (EDCs) Effects on Tumour Microenvironment and Cancer Progression: Emerging Contribution of RACK1

Endocrine disruptors (EDCs) can display estrogenic and androgenic effects, and their exposure has been linked to increased cancer risk. EDCs have been shown to directly affect cancer cell regulation and progression, but their influence on tumour microenvironment is still not completely elucidated. In this context, the signalling hub protein RACK1 (Receptor for Activated C Kinase 1) could represent a nexus between cancer and the immune system due to its roles in cancer progression and innate immune activation. Since RACK1 is a relevant EDCs target that responds to steroid-active compounds, it could be considered a molecular bridge between the endocrine-regulated tumour microenvironment and the innate immune system. We provide an analysis of immunomodulatory and cancer-promoting effects of different EDCs in shaping tumour microenvironment, with a final focus on the scaffold protein RACK1 as a pivotal molecular player due to its dual role in immune and cancer contexts.

Beyond Glucocorticoids: Integrating Dehydroepiandrosterone (DHEA) into Animal Welfare Research

Animal welfare researchers are committed to identifying novel measures for enhancing the quality of life of individual animals. Recently, welfare scientists have emphasized the need for tracking multiple indicators of an animal's behavioral, emotional and mental health. Researchers are currently focused on integrating non-invasive physiological biomarkers to gain insight into an individual's welfare status. Most commonly, the animal welfare community has analyzed glucocorticoid hormones and their metabolites as a measure of stress. While glucocorticoids provide valuable information about hypothalamic-pituitary-adrenal (HPA) axis activity, there are limitations to utilizing these hormones as the sole measure of long-term stress and welfare. Other biomarkers, such as dehydroepiandrosterone and its sulfate ester-collectively referred to as DHEA(S)-help provide a more complete picture of HPA activity. DHEA(S) counteracts the effects glucocorticoids by having anti-aging, immune-enhancing and neuroprotective properties. Recent studies have examined the ratio of glucocorticoids to DHEA(S) as a way to better understand how the HPA axis is functioning. There is evidence that this ratio serves as an indicator of immune function, mental health, cognitive performance and overall welfare. We review studies that employed the glucocorticoid:DHEA(S) ratio, outline methodological considerations and discuss how researchers can integrate glucocorticoids, DHEA(S) and the glucocorticoid:DHEA(S) ratio into welfare assessments.

Neuroendocrine Modulation of the Immune Response after Trauma and Sepsis: Does It Influence Outcome?

Although the treatment of multiple-injured patients has been improved during the last decades, sepsis and multiple organ failure (MOF) still remain the major cause of death. Following trauma, profound alterations of a large number of physiological systems can be observed that may potentially contribute to the development of sepsis and MOF. This includes alterations of the neuroendocrine and the immune system. A large number of studies focused on posttraumatic changes of the immune system, but the cause of posttraumatic immune disturbance remains to be established. However, an increasing number of data indicate that the bidirectional interaction between the neuroendocrine and the immune system may be an important mechanism involved in the development of sepsis and MOF. The aim of this article is to highlight the current knowledge of the neuroendocrine modulation of the immune system during trauma and sepsis.

Protocol for understanding acute sarcopenia: a cohort study to characterise changes in muscle quantity and physical function in older adults following hospitalisation

BACKGROUND

Older adults are vulnerable to the effects of acute sarcopenia (acute muscle insufficiency) following hospitalisation. However, this condition remains poorly characterised to date. It is hypothesised that acute sarcopenia arises due to a combination of bed rest and inflammatory surge. This study aims to characterise changes in muscle quantity and function, determining which factors (clinical and biological) are most predictive, and how these relate to change in physical function at 13 weeks.

METHODS

This study will include three groups of patients aged 70 years and older; patients undergoing elective colorectal surgery, patients admitted for emergency abdominal surgery, and patients admitted under general medicine with acute bacterial infections. Changes in muscle quantity (Bilateral Anterior Thigh Thickness with ultrasound and bioelectrical impedance analysis) and muscle function (muscle strength, physical performance) within 1 week of hospitalisation or surgery will be characterised, with follow-up of patients at 13 weeks. Physical function will be measured using the Patient Reported Outcome Measures Information System, and the Short Physical Performance Battery (or gait speed alone within 1 week of surgery).

DISCUSSION

This study will fully characterise changes in muscle quantity and function in hospitalised older adults and enable risk stratification towards targeted interventions in clinical practice. The results of this study will inform further research involving interventions to ameliorate changes.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03858192 ; Prospectively registered 28th February 2019.

Environmental enrichment modulates inflammation during development in long-evans rats (Rattus norvegicus)

It is unknown whether increased production of pro-inflammatory mediators during the life span is caused by aging per se or via the combination of a cumulative allostatic load due to life challenges. This study aimed to investigate the long-term effects of stress and environmental enrichment on the inflammatory status associated with aging in rats. Animals were assigned to the following five treatment groups: chronic stress with and without environmental enrichment; acute stress with and without environmental enrichment; control animals. Enrichment was provided as an open field containing novel objects (30 min three times per week). Animals assigned to chronic stress groups were exposed to predator sound stressors (e.g., hawk sound) for 30 min daily, while animals assigned to acute stress groups were exposed once a week for 30 min. The interaction between the hypothalamic-pituitary-adrenal axis and the immune system was investigated by measuring metabolized dehydroepiandrosterone (DHEA) levels and peripheral levels of the cytokines IL-6 and IL-10. Results suggested that inflamm-aging was more pronounced in animals with low DHEA levels, which in turn were affected by exposure to environmental enrichment and acute stress. This study showed that environmental enrichment and acute stress can significantly attenuate disruptions in DHEA production, consequently contributing to improved neuroimmune function of aging animals.

Mapping the Steroid Response to Major Trauma From Injury to Recovery: A Prospective Cohort Study

CONTEXT

Survival rates after severe injury are improving, but complication rates and outcomes are variable.

OBJECTIVE

This cohort study addressed the lack of longitudinal data on the steroid response to major trauma and during recovery.

DESIGN

We undertook a prospective, observational cohort study from time of injury to 6 months postinjury at a major UK trauma centre and a military rehabilitation unit, studying patients within 24 hours of major trauma (estimated New Injury Severity Score (NISS) > 15).

MAIN OUTCOME MEASURES

We measured adrenal and gonadal steroids in serum and 24-hour urine by mass spectrometry, assessed muscle loss by ultrasound and nitrogen excretion, and recorded clinical outcomes (ventilator days, length of hospital stay, opioid use, incidence of organ dysfunction, and sepsis); results were analyzed by generalized mixed-effect linear models.

FINDINGS

We screened 996 multiple injured adults, approached 106, and recruited 95 eligible patients; 87 survived. We analyzed all male survivors <50 years not treated with steroids (N = 60; median age 27 [interquartile range 24-31] years; median NISS 34 [29-44]). Urinary nitrogen excretion and muscle loss peaked after 1 and 6 weeks, respectively. Serum testosterone, dehydroepiandrosterone, and dehydroepiandrosterone sulfate decreased immediately after trauma and took 2, 4, and more than 6 months, respectively, to recover; opioid treatment delayed dehydroepiandrosterone recovery in a dose-dependent fashion. Androgens and precursors correlated with SOFA score and probability of sepsis.

CONCLUSION

The catabolic response to severe injury was accompanied by acute and sustained androgen suppression. Whether androgen supplementation improves health outcomes after major trauma requires further investigation.

Free light chains as an emerging biomarker in saliva: Biological variability and comparisons with salivary IgA and steroid hormones

BACKGROUND

Salivary free light chains (FLCs) are an emerging biomarker in health and behavioural research. However, little is known regarding biological variability of salivary FLCs and how they relate to other established salivary biomarkers. This study aimed to investigate the diurnal and day-to-day variation of salivary FLCs and their relationship with salivary IgA and steroid hormones.

METHODS

A total of 46 healthy adults participated in studies exploring the biological variability of FLCs. Diurnal variation was investigated by collecting saliva samples immediately upon waking, 0.5 h, 3 h, 6 h, 9 h and 14 h post-waking. Saliva samples were assessed for FLCs, IgA, cortisol and dehydroepiandrosterone (DHEA). Between-day variation in FLCs and IgA was assessed by collecting saliva samples immediately upon waking for seven consecutive days. Participants underwent a dental examination to exclude oral health as a potential confounding variable. Within and between-person day-to day variation was explored in relation to a range of different factors: awakening time, sleep, exercise, well-being and alcohol consumption.

RESULTS

Salivary secretion rates of FLCs decreased following waking and up to 3 h post-waking and then plateaued. This same pattern was observed for IgA. DHEA was stable upon waking and higher levels were seen in the morning with significantly lower levels thereafter. Cortisol levels significantly increased 0.5 h post-waking then continued to decline across the day. FLCs were significantly correlated with IgA but not cortisol or DHEA. Both FLCs and IgA parameters showed day-to-day variability, with coefficients of variation ≥ 40%. Earlier waking time was significantly correlated with higher FLC and IgA secretion rates. Inter-person differences in saliva parameter variability were observed but the degree of variation in FLCs and IgA was related within person. Inter-person day-to-day variation appeared to be uninfluenced by lifestyle or behavioural factors.

CONCLUSIONS

Saliva FLCs secretion exhibits diurnal fluctuation that mirrors IgA fluctuation. Findings strongly indicate salivary FLC secretion is orchestrated by local plasma cells. FLCs and IgA both showed notable variability day-to-day, which was similar within person and influenced by awakening time. FLCs offer a promising adjunct to IgA in the measurement of oral immune activation.

High perceived stress in women is linked to oxidation, inflammation and immunosenescence

Chronic stress situations lead to an impairment of immune response and higher oxidative and inflammatory stress, which are important underlying mechanisms of the ageing process. However, given that the physiological stress response depends on the subjective appraisal of a given stressor, the aim of the study was to investigate the effect that different degrees of perceived stress have, regardless of their type, on immune functions, oxidative and inflammatory stress and ageing rate of women (30-50 years old). For that purpose, a group of 49 women was classified, according to their scores obtained in the perceived stress scale (PSS), into low (n = 23), moderate (n = 14) and high (n = 12) degree of perceived stress. The immune functions studied were: neutrophil and lymphocyte chemotaxis, neutrophil phagocytic capacity, natural killer activity, lymphoproliferation and LPS-stimulated cytokine release. Basal cytokine release was studied as an inflammatory stress marker. Antioxidant (superoxide dismutase, glutathione peroxidase and reductase activities, and reduced glutathione) and oxidant compounds (oxidized glutathione and malondialdehyde) were also investigated in whole blood as markers of oxidative stress. The results show that, in general, women with a moderate or high degree of perceived stress have a worse immune functionality and higher oxidative and inflammatory stress compared to women with low stress perception. In addition, a positive correlation was found between PSS scores and the biological age of each woman (P ≤ 0.001). In conclusion, high levels of perceived stress in women are associated with a higher oxidative and inflammatory stress and immunosenescence, which seem to accelerate their ageing rate.

Dehydroepiandrosterone: a potential therapeutic agent in the treatment and rehabilitation of the traumatically injured patient

Severe injuries are the major cause of death in those aged under 40, mainly due to road traffic collisions. Endocrine, metabolic and immune pathways respond to limit the tissue damage sustained and initiate wound healing, repair and regeneration mechanisms. However, depending on age and sex, the response to injury and patient prognosis differ significantly. Glucocorticoids are catabolic and immunosuppressive and are produced as part of the stress response to injury leading to an intra-adrenal shift in steroid biosynthesis at the expense of the anabolic and immune enhancing steroid hormone dehydroepiandrosterone (DHEA) and its sulphated metabolite dehydroepiandrosterone sulphate (DHEAS). The balance of these steroids after injury appears to influence outcomes in injured humans, with high cortisol: DHEAS ratio associated with increased morbidity and mortality. Animal models of trauma, sepsis, wound healing, neuroprotection and burns have all shown a reduction in pro-inflammatory cytokines, improved survival and increased resistance to pathological challenges with DHEA supplementation. Human supplementation studies, which have focused on post-menopausal females, older adults, or adrenal insufficiency have shown that restoring the cortisol: DHEAS ratio improves wound healing, mood, bone remodelling and psychological well-being. Currently, there are no DHEA or DHEAS supplementation studies in trauma patients, but we review here the evidence for this potential therapeutic agent in the treatment and rehabilitation of the severely injured patient.

Effects of nucleotide supplementation on growth performance, nutrient digestibility, and immune blood profiles related to foot-and-mouth disease in vaccinated growing pigs

A 6 wk trial was conducted to evaluate the effects of nucleotide supplementation in improving performance, nutrient digestibility, and immune blood profiles so as to reduce foot-and-mouth disease (FMD) vaccine stress in growing pigs. A total of 120 growing pigs [(Yorkshire × Landrace) × Duroc] with an average body weight (BW) of 25.76 ± 1.83 kg were used. Pigs were allocated to one of three treatments (eight pens per treatment; three barrows and two gilts per pen) based on BW and sex. Pigs were injected with FMD vaccine at 84 d of age (2 wk after experiment started). Dietary treatments consisted of (1) CON: corn–soybean-meal-based diet, (2) NUC1: CON + 0.5% nucleotide, and (3) NUC2: CON + 1.0% nucleotide. In the current study, the growth performance of gain:feed ratio (G:F), the apparent total tract digestibility of dry matter and nitrogen was linearly (P < 0.05) increased with the increasing level of nucleotide. After injection, the concentration of cortisol and epinephrine was decreased (P < 0.05) linearly in nucleotide treatments. In conclusion, nucleotide supplementation to FMD vaccinated pigs showed positive effects on improving performance, immune system health, and reducing vaccine stress in growing pigs.

Short- and long-term mortality in major non-cardiac surgical patients admitted to the intensive care unit

BACKGROUND

The aim of this register-based cohort study was to characterize patients admitted to the intensive care unit (ICU) following non-cardiac surgery and identify risk factors associated with 30-days, 90-days and 1-year mortality after ICU admission.

METHODS

Patients aged 18+ years admitted to the intensive care unit within 30-days of non-cardiac surgery at four Capital Region hospitals in Denmark between January 2005 and December 2014 were included. Patients were identified through the Danish National Patient Register. The outcomes were 30-days, 90-days and 1-year mortality after ICU admission. Unadjusted and multivariate logistic regression analyses were performed to identify independent risk factors of mortality.

RESULTS

The study included 3311 ICU patients. Gastrointestinal surgery accounted for 71.3%, orthopaedic surgery for 18.4% and urologic surgery for 10.2% of the population. For the total population, the median length of stay in hospital was 18 days (9-36, 25th-75th percentile) and 2 days (1-4, 25th-75th percentile) in the ICU. Thirty-days, 90-days and 1-year mortality were 37.8%, 44.5% and 51.2% respectively. Mortality within the ICU was 22.3% while the post-ICU in-hospital mortality was 19.4%. Higher age, comorbidity, delayed ICU admission, acute surgery, and gastrointestinal and orthopaedic surgery increased 30-days, 90-days and 1-year mortality.

CONCLUSIONS

Short- and long-term mortality in non-cardiac surgical patients admitted to the ICU is very high, especially among the elderly comorbid patients undergoing acute surgery. Future research should focus on targeting clinically modifiable risk factors and performing tailored treatment for these high-risk patients.

A High Serum Cortisol/DHEA-S Ratio Is a Risk Factor for Sarcopenia in Elderly Diabetic Patients

Context

Elderly patients with type 2 diabetes mellitus (T2DM) have a high prevalence of frailty and/or sarcopenia. Sarcopenia is thought to be related to discordant secretions of the adrenal hormones cortisol and dehydroepiandrosterone (DHEA), as well as the sulfate ester of DHEA (DHEA-S). The current study sought to evaluate the risk factors for sarcopenia in elderly patients with T2DM.

Design and Patients

We enrolled 108 consecutive elderly patients aged ≥65 years with T2DM (mean age, 76.2 ± 7.3 years; 43.5% males). Sarcopenia was assessed and diagnosed based on the Asian version of the diagnostic criteria regarding muscular strength, physical function, and muscle mass. We assessed various physical parameters, blood tests, and atherosclerosis markers and statistically determined the risk factors for sarcopenia.

Results

Multiple regression analysis showed that the independent risk factors for sarcopenia were a serum cortisol/DHEA-S ratio ≥0.2, diastolic blood pressure <70 mm Hg, Hb concentration <13 g/dL, and an ankle brachial index <1.0. The strongest risk factor for sarcopenia was a serum cortisol/DHEA-S ratio ≥0.2. An increase in the serum cortisol/DHEA-S ratio reflected higher cortisol values and lower DHEA-S values in patients with sarcopenia compared with those in nonsarcopenic patients. The concentrations of cortisol and DHEA-S, as well as the cortisol/DHEA-S ratio, changed in accordance with the severity of sarcopenia.

Conclusions

A relative increase in cortisol may reflect the presence of stress and stimulate muscle catabolism, whereas a relative decrease in DHEA-S may cause a decrease in the anabolic action of DHEA on muscle; the combination of these factors may lead to sarcopenia.

Exercise training-induced changes in metabolic syndrome parameters, carotid wall thickness, and thyroid function in middle-aged women with subclinical hypothyroidism

This study analyzed the differences in effects of a 12-week combination of exercise training program with resistance training and aerobic exercises on the risk factors of metabolic syndrome, carotid wall thickness, and thyroid function, between subclinical hypothyroidism patients and obese groups, in middle-aged women. Subjects consisted of either 20 middle-aged women in the subclinical hypothyroidism (SCH) group or 20 obese (body mass indices [BMI], ≥ 25 kg/m²) women without hypothyroidism in the obese (OB) group. The body composition, blood lipid factors, hormones associated with thyroid functions, blood pressure (BP), and carotid intima-media thickness were measured, while physical fitness was ascertained. In the SCH group, waist circumference (WC) and high-density lipoprotein cholesterol values were outside the normal ranges, while WC and systolic BP (SBP) were outside the normal ranges in the OB group. Following the 12-week training program, significantly positive changes occurred in body fat percentage, sit and reach test results, and SBP (p < 0.05) in the SCH group, while in the OB group, significantly positive changes in BMI, WC, sit and reach test results, SBP, and diastolic BP (DBP, p < 0.05) were observed. In addition, both groups showed significant decreases in intima-media thickness of the right carotid bifurcation (p < 0.05). However, in the two groups, the 12-week exercise training program did not have similar significant impact on the hormones related to thyroid functions and blood lipids. Therefore, further research on exercise training that can effectively induce changes in the hormones associated with thyroid functions in patients with subclinical hypothyroidism is necessary.

Aging, inflammation and cancer

Aging is a key aspect of neoplasia at the level of cells, individuals and populations. Unrestrained expression and production of inflammatory mediators is a key feature of aging at the cellular and organism level. Inflammatory cells and mediators are a key component of the tumor microenvironment and drive tumor progression. Non-resolving smoldering inflammation increases the risk of cancer (the extrinsic pathway connecting inflammation and cancer). In the intrinsic pathway, genetic events that cause neoplasia (oncogenes and oncosupressor genes) orchestrate the construction of cancer-related inflammation. We argue that uncontrolled smoldering inflammation drives carcinogenesis in aging and acts as a common denominator linking aging and cancer.

Prognostic Value of Dehydroepiandrosterone Sulfate for Patients With Cardiovascular Disease: A Systematic Review and Meta-Analysis

BACKGROUND

The aim of the present study was to estimate the impact of dehydroepiandrosterone sulfate (DHEAS) on the prognosis of patients with cardiovascular disease by performing a systematic review and meta-analysis.

METHODS AND RESULTS

The Embase, PubMed, Web of Science, CNKI, and WanFang databases were searched up to September 5, 2016, to identify eligible studies. The quality of each study was assessed using the Newcastle-Ottawa Scale. The association between DHEAS, either on admission or at discharge, and cardiovascular disease outcomes were reviewed. The overall risk ratio for the effect of DHEAS on all-cause mortality and fatal and nonfatal cardiovascular events was pooled using a fixed-effects or a random-effects model. The publication bias was evaluated using funnel plots. Twenty-five studies were included for systematic review. The follow-up duration ranged from 1 to 19 years. Eighteen studies were included in the meta-analysis. We found that lower DHEAS levels indicated a significant increased risk for all-cause mortality (risk ratio, 1.47; 95% CI, 1.38-1.56 [P<0.00001]), fatal cardiovascular event (risk ratio, 1.58; 95% CI, 1.30-1.91 [P<0.00001]), and nonfatal cardiovascular event (risk ratio, 1.42; 95% CI, 1.24-1.62 [P<0.0001]) in patients with cardiovascular disease.

CONCLUSIONS

Patients with cardiovascular disease who have lower DHEAS levels may have poorer prognosis than those with higher DHEAS levels.

Cortisol and DHEA in development and psychopathology

Dehydroepiandrosterone (DHEA) and cortisol are the most abundant hormones of the human fetal and adult adrenals released as end products of a tightly coordinated endocrine response to stress. Together, they mediate short- and long-term stress responses and enable physiological and behavioral adjustments necessary for maintaining homeostasis. Detrimental effects of chronic or repeated elevations in cortisol on behavioral and emotional health are well documented. Evidence for actions of DHEA that offset or oppose those of cortisol has stimulated interest in examining their levels as a ratio, as an alternate index of adrenocortical activity and the net effects of cortisol. Such research necessitates a thorough understanding of the co-actions of these hormones on physiological functioning and in association with developmental outcomes. This review addresses the state of the science in understanding the role of DHEA, cortisol, and their ratio in typical development and developmental psychopathology. A rationale for studying DHEA and cortisol in concert is supported by physiological data on the coordinated synthesis and release of these hormones in the adrenal and by their opposing physiological actions. We then present evidence that researching cortisol and DHEA necessitates a developmental perspective. Age-related changes in DHEA and cortisol are described from the perinatal period through adolescence, along with observed associations of these hormones with developmental psychopathology. Along the way, we identify several major knowledge gaps in the role of DHEA in modulating cortisol in typical development and developmental psychopathology with implications for future research.

Dehydroepiandrosterone improves the ovarian reserve of women with diminished ovarian reserve and is a potential regulator of the immune response in the ovaries

Diminished ovarian reserve (DOR) has a high morbidity rate worldwide and has become a primary cause of infertility. DOR is a daunting obstacle in in vitro fertilization (IVF) and leads to poor ovarian response, high cancellation rates, poor IVF outcomes, and low pregnancy rates. Abnormal autoimmune function may also contribute to DOR. Dehydroepiandrosterone (DHEA) is a C19 androgenic steroid. DHEA is secreted mainly by the adrenal gland, and its secretion declines with age. DHEA has a pro-inflammatory immune function that opposes cortisol. The cortisol to DHEA ratio increases with age, which may lead to decreased immune function. DHEA supplementation helps improve this situation. A number of clinical case control studies and several prospective randomized clinical trials have observed a positive effect of DHEA supplementation in women with DOR. However, the underlying mechanism by which DHEA improves ovarian reserve remains unclear. DHEA functions as an immune regulator in many different tissues in mammals and may also play an important role in regulating the immune response in the ovaries. The conversion of DHEA to downstream sex steroids may allow it to regulate the immune response there. DHEA can also enhance the Th1 immune response and regulate the balance of the Th1/Th2 response. DHEA treatment can increase selective T lymphocyte infiltration in mice, resulting in a decline in the CD4+ T lymphocyte population and an upregulation of the CD8+ T lymphocyte population in ovarian tissue, thus regulating the balance of CD4+/CD8+ T cells. This review mainly focuses on how DHEA supplementation affects regulation of the immune response in the ovaries.

Response to an Escherichia coli K88 oral challenge and productivity of weanling pigs receiving a dietary nucleotides supplement

BACKGROUND

Dietary nucleotides, considered as antibiotics alternative, were shown to have positive effects on intestinal hyperaemia, systemic immunity, small-intestinal growth, and hepatic composition in pigs. However, there is no previous research on nucleotide supplementation in weanling pigs under an oral challenged E. coli K88. Therefore, 2 experiments were conducted to investigate the effects of dietary nucleotides on weanling pig growth performance, nutrient digestibility, fecal score, and blood profile after being orally challenged with E. coli K88.

METHODS

In Exp. 1, a total of 140 weanling pigs [8.33 ± 0.33 kg of body weight (BW), 28-d old] were used in this 42-d feeding trial. Pigs were distributed into 1 of 4 treatments, 5 pigs/pen (3 barrows and 2 gilts) and 7 pens/treatment. Treatments were a control basal diet (CON) or the CON supplemented with 150 (R150), 220 (R220), or 275 (R275) mg/kg to give the three treatment diets. In Exp. 2, 28 weanling pigs (BW = 8.40 ± 0.22 kg, 28-d old) were distributed into 1 of 4 treatments to give 1 pig/pen and 7 pens/treatment in a 42-d feeding and challenge trial. Dietary treatments were the same as in Exp. 1. On d 14, all those pigs (BW = 13.3 ± 0.15 kg, 42-d old) were orally dosed with 1.5 mL suspension containing 10(10) cfu/mL of E. coli K88. Twenty four hours after challenge, blood and excreta samples were collected from each pigs for analysis. Fecal scores were measured on d 7, 14, 21, and 28 of the study.

RESULTS

In Exp. 1, overall BW, average daily gain (ADG), gain/feed (G/F) ratio, and nutrient digestibilities were lower (P < 0.05) in CON group compared with the nucleotides fed pigs. In Exp. 2, after challenge, IgA, IgM, and IGF-I were higher (P < 0.05) in the nucleotide groups compared with CON. However, the nucleotide groups had lower (P < 0.05) cortisol and TNF-α compared with CON. Fecal E. coli counts and fecal score for the nucleotide groups were lower (P < 0.05) than for CON.

CONCLUSIONS

In conclusion, dietary nucleotides supplementation could improve growth performance, nutrient digestibility, immune status, microbial balance, reduce diarrhea, and provide protection against enterotoxigenic E. coli K88 infection in weanling pigs.

Older Patients Are Immunocompromised by Cytokine Depletion and Loss of Innate Immune Function After HIP Fracture Surgery

PURPOSE/INTRODUCTION

We have examined the immune status of elderly patients who underwent surgery for a hip fracture, an injury associated with poor postoperative outcomes, to identify specific immune defects.

METHODS

In a cohort observational study, 16 patients undergoing surgery for hip fractures had immune function evaluation prior to surgery, and then at 3 and 7 days postoperatively, using flow cytometry for phenotype and for monocyte and granulocyte phagocytic function and respiratory burst. Serum samples were stored and batch analyzed using a human cytokine 25-plex panel.

RESULTS

We report significant loss of innate immune function, related specifically to reduced granulocyte numbers by day 7 (P < .0001, flow cytometry; P < .05 white blood cells), and although granulocyte ability to take up opsonized Escherichia coli was increased (P < .05), the ability of those cells to generate a respiratory burst was reduced at days 3 and 7 (P < .05). Monocyte respiratory burst was also significantly reduced (P < .05). Serum cytokine levels indicated very poor T-cell function.

CONCLUSION

We have demonstrated that the antimicrobial immune response is profoundly reduced after surgery in elderly patients with hip fractures. The effect was sustained up to 7 days postoperatively, identifying these patients as particularly vulnerable to bacterial infections.

Immunesenescence and inflammaging: A contributory factor in the poor outcome of the geriatric trauma patient

Compared to younger patients, traumatic injury in older patients is associated with increased mortality and a range of adverse outcomes such as higher rates of infectious episodes, longer length of hospital stay and poor functional outcome at follow up. Data emerging from human and murine-based studies suggest age-related changes in immune function, collectively termed immunesenescence, and the chronic sub-clinical systemic inflammatory state of older adults, termed inflammaging, may contribute to these poor outcomes. Here, we review the findings of these studies, whose results demonstrate that the geriatric trauma patient elicits an immune response to injury that is distinct to that of younger adults, being characterised by reduced immune cell activation, impaired function and abnormal haematopoiesis, defects that are accompanied by an altered inflammatory response that fails to return to a homeostatic baseline in the days following injury. Although considerable evidence is accumulating that demonstrates clear and significant age-related differences in the immune and inflammatory response to traumatic injury, our current understanding of the mechanism(s) that underlie these changes is limited. Future studies that provide a mechanistic explanation for the unique immune and inflammatory response of older adults to traumatic injury are therefore essential if we are to determine whether manipulation of the immune system has potential as a future therapeutic strategy by which to improve the outcome of the geriatric trauma patient.

Development of depressive symptoms post hip fracture is associated with altered immunosuppressive phenotype in regulatory T and B lymphocytes

Hip fracture is a common physical trauma in older adults that is also associated with a high incidence of new onset depression. The immune system declines with age and is also compromised by physical and psychological stress. This study examined whether hip fracture and depressive symptoms had additive effects upon the aged immune system that might contribute to poor health outcomes after hip fracture. We assessed the frequency of regulatory T cells, T_regs (CD4⁺ CD25⁺ Foxp3⁺) and IL10 production by CD4 T cells, and the frequency and IL10 production by regulatory B cells, B_regs (CD19⁺ CD24^hi CD38^hi) in 101 hip fracture patients (81 female) 6 weeks after injury and 43 healthy age-matched controls (28 female). 38 hip fracture patients (37 %) developed depressive symptoms. Hip fracture did not have an effect on circulating T_regs frequency but a significant reduction in the frequency of B_regs was observed in patients who developed depression compared with non-depressed patients (p = 0.001) or healthy controls (p < 0.001). B_regs also showed a significant decline in IL10 production in depressed hip fracture patients compared with controls (p = 0.04) and non-depressed patients (p = 0.01). In contrast, there was an increase in IL10 production by CD4 T cells in hip fracture patients with new onset depression compared to hip fracture patients without depression (p = .04) and healthy controls (p = .02). We conclude that the reduced immunity associated with new onset depression post hip fracture could include a contribution by heightened T_regs function.

Altered neutrophil functions in elderly patients during a 6-month follow-up period after a hip fracture

BACKGROUND

Fracture of the hip (HF) is a significant cause of morbidity and mortality in elderly individuals. HF is an acute stress that triggers a state of inflammation which may affect immune responses and physical recovery.

METHODS

Longitudinal study of the impact of HF on the functions of polymorphonuclear neutrophils (PMNs) in elderly subjects. Data were recorded prior to surgery, 6weeks and 6months later.

RESULTS

PMN functions were severely impaired shortly after HF (chemotaxis, phagocytosis, superoxide production) but there was a time-related recovery of some PMN functions (chemotaxis, phagocytosis) over time, except in the case of superoxide production. Whereas FcγRII (CD32) expression remained unchanged, FcγRIII (CD16) increased from low values before surgery to levels of controls 6months post-surgery. This was also the case for the C5a complement receptor and CD11b. TLR2 and TLR4 expressions were unchanged. Cytokine and chemokine secretions by stimulated PMN were altered. TNFα and IL-10 secretions were increased following HF but IL-8 secretion was decreased. Impaired PMN functions prior to surgery were related to alterations in PI3K and NF-κB signaling pathways. Recovery of these functions paralleled increased PI3K activity, although superoxide production remained low. Sustained activation of the NF-κB pathway by TNFα has been reported to involve upregulation of IKKβ kinase activity. Activated IKKβ kinase inhibits ERK1/2 and results in concomitant downstream inhibition of NADPH oxidase complex which can account for sustained impaired production of ROS in HF patients.

CONCLUSION

Our data showed that the stress caused by HF negatively affects initial PMN responses shortly after the event and that may negatively influence clinical outcomes such as resolving long-term inflammation and recovery, as well as explaining susceptibility to opportunistic infections.

NK cell immunesenescence is increased by psychological but not physical stress in older adults associated with raised cortisol and reduced perforin expression

NK cell cytotoxicity (NKCC) reduces with age and this has been associated previously with increased mortality. The immune response is also modulated by stress, and here, we assessed the effect of the physical stress of hip fracture and the psychological stress of depression on NKCC in an aged immune system. NKCC was assessed in 101 hip fracture patients (81 female) 6 weeks and 6 months after injury and in 50 healthy age-matched controls (28 female). Thirty-eight patients were depressed at 6 weeks post-injury, and NKCC was reduced in patients who developed depression compared with non-depressed hip fracture patients (p = 0.004) or controls (p < 0.02). NKCC remained lower in the depressed patients compared to those without depression 6 months post-fracture (p = 0.017). We found reduced expression of perforin in NK cells of depressed hip fracture patients compared with controls at 6 weeks (p = 0.001) post-fracture. Serum cortisol levels were also elevated in patients with depression compared to non-depressed patients at 6 weeks (p = 0.01) and 6 months (p = 0.05). NK cells treated with dexamethasone showed a concentration-dependent reduction in NKCC and perforin expression. We propose that depression is the major factor affecting NK cell immunity after hip fracture.

Depressive symptoms post hip fracture in older adults are associated with phenotypic and functional alterations in T cells

Background

Ageing is accompanied by reduced immunity, termed immunesenescence. The immune system does not act in isolation and is sensitive to both psychological and physical stress. Hip fracture is a common physical stressor in older adults with a high incidence of new onset depression, which relates to poorer prognosis. We therefore set out to examine the possible synergistic effects of physical stress (hip fracture) and psychological stress (depressive symptoms) on the aged immune system.

Results

T cell phenotype and function was assessed in 101 hip fracture patients (81 female) 6 weeks after hip fracture and 43 healthy age-matched controls (26 female). 38 fracture patients had depressive symptoms at 6 weeks. T cell frequency (p = .01) and numbers (p = .003) were both lower in depressed hip fracture patients compared to healthy controls. The frequency of senescent CD28^-ve (p = .001), CD57^+ve (p = .001), KLRG1^+ve (p = .03) CD8 T cells, as well as senescent CD28^-ve CD4^+ve (p = .01) and CD57^+ve CD4^+ve (p = .003) T cells were higher in depressed hip fracture patients compared with healthy controls and the frequency of CD28^-ve CD8 T cells was also higher when compared to patients with hip fracture alone (p = .01). Additionally, activated CD69^+ve (p = .005) and HLADR^+ve (p < .001) CD8 T cells, were also higher in depressed hip fracture patients compared to healthy controls. On examining cytokine production by activated T cells, a significant increase in TNFα (p = .03) and IL6 (p = .04) production was observed in CD4 T cells from hip fracture patients with depressive symptoms compared to healthy controls.

Conclusions

As none of the patients in the study had a prior history of depression, our data suggest that the development of depressive symptoms in hip fracture patients is associated with altered T cell phenotype and increased pro-inflammatory function which is not seen in patients who do not develop depression after hip fracture. Treating depressive symptoms promptly in hip fracture patients may therefore improve immunity and outcomes in these patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s12979-014-0025-5) contains supplementary material, which is available to authorized users.

The systemic immune response to trauma: an overview of pathophysiology and treatment

Improvements in the control of haemorrhage after trauma have resulted in the survival of many people who would otherwise have died from the initial loss of blood. However, the danger is not over once bleeding has been arrested and blood pressure restored. Two-thirds of patients who die following major trauma now do so as a result of causes other than exsanguination. Trauma evokes a systemic reaction that includes an acute, non-specific, immune response associated, paradoxically, with reduced resistance to infection. The result is damage to multiple organs caused by the initial cascade of inflammation aggravated by subsequent sepsis to which the body has become susceptible. This Series examines the biological mechanisms and clinical implications of the cascade of events caused by large-scale trauma that leads to multiorgan failure and death, despite the stemming of blood loss. Furthermore, the stark and robust epidemiological finding--namely, that age has a profound influence on the chances of surviving trauma irrespective of the nature and severity of the injury--will be explored. Advances in our understanding of the inflammatory response to trauma, the impact of ageing on this response, and how this information has led to new and emerging treatments aimed at combating immune dysregulation and reduced immunity after injury will also be discussed.

Post-traumatic immunosuppression is reversed by anti-coagulated salvaged blood transfusion: deductions from studying immune status after knee arthroplasty

Major trauma increases vulnerability to systemic infections due to poorly defined immunosuppressive mechanisms. It confers no evolutionary advantage. Our objective was to develop better biomarkers of post-traumatic immunosuppression (PTI) and to extend our observation that PTI was reversed by anti-coagulated salvaged blood transfusion, in the knowledge that others have shown that non-anti-coagulated (fibrinolysed) salvaged blood was immunosuppressive. A prospective non-randomized cohort study of patients undergoing primary total knee arthroplasty included 25 who received salvaged blood transfusions collected post-operatively into acid-citrate-dextrose anti-coagulant (ASBT cohort), and 18 non-transfused patients (NSBT cohort). Biomarkers of sterile trauma included haematological values, damage-associated molecular patterns (DAMPs), cytokines and chemokines. Salvaged blood was analysed within 1 and 6 h after commencing collection. Biomarkers were expressed as fold-changes over preoperative values. Certain biomarkers of sterile trauma were common to all 43 patients, including supranormal levels of: interleukin (IL)-6, IL-1-receptor-antagonist, IL-8, heat shock protein-70 and calgranulin-S100-A8/9. Other proinflammatory biomarkers which were subnormal in NSBT became supranormal in ASBT patients, including IL-1β, IL-2, IL-17A, interferon (IFN)-γ, tumour necrosis factor (TNF)-α and annexin-A2. Furthermore, ASBT exhibited subnormal levels of anti-inflammatory biomarkers: IL-4, IL-5, IL-10 and IL-13. Salvaged blood analyses revealed sustained high levels of IL-9, IL-10 and certain DAMPs, including calgranulin-S100-A8/9, alpha-defensin and heat shock proteins 27, 60 and 70. Active synthesis during salvaged blood collection yielded increasingly elevated levels of annexin-A2, IL-1β, Il-1-receptor-antagonist, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-17A, IFN-γ, TNF-α, transforming growth factor (TGF)-β1, monocyte chemotactic protein-1 and macrophage inflammatory protein-1α. Elevated levels of high-mobility group-box protein-1 decreased. In conclusion, we demonstrated that anti-coagulated salvaged blood reversed PTI, and was attributed to immune stimulants generated during salvaged blood collection.

Bereavement reduces neutrophil oxidative burst only in older adults: role of the HPA axis and immunesenescence

Background

The effect of the chronic stress of bereavement on immunity is poorly understood. Previous studies have demonstrated negative effects on immunity in older adults, and those who report higher depressive symptoms. The aim of the present study was to compare the effect of bereavement on neutrophil function in healthy young and old adults, also assessing serum levels of the stress hormones, cortisol and dehydroepiandrosterone sulphate (DHEAS). 41 young (mean age 32 years) and 52 older adults (mean age 72 years), bereaved and non-bereaved, took part in the study. They completed questionnaires on socio-demographic and health behaviour characteristics, as well as psychosocial variables, and provided a blood sample for analysis of neutrophil function (phagocytosis and reactive oxygen species (ROS) production) and stress hormone analysis.

Results

Bereaved participants in both age groups reported more symptoms of depression and anxiety than controls and scored moderately highly on bereavement-specific questionnaires for these symptoms. Despite this, young bereaved participants showed robust neutrophil function when compared to age-matched non-bereaved controls, and comparable stress hormone levels, while reduced neutrophil ROS production and raised stress hormone levels (cortisol:DHEAS ratio) were seen in the older bereaved group compared to their age-matched controls.

Conclusions

Reduced neutrophil function among older bereaved participants may be the result of the inability to maintain stress hormone balance, specifically the cortisol:DHEAS ratio.