Acute effects of recombinant human interleukin-6 on endocrine and central nervous sleep functions in healthy men

The circadian rhythm as therapeutic target in inflammatory bowel disease

The primary objectives of the management of patients with inflammatory bowel disease (IBD) are to prevent IBD flares, prevent/delay disease progression and improve patients' quality of life. To this end, one needs to identify risk factor(s) associated with flare-ups and disease progression. We posit that disruption of circadian rhythms is one of the key factors that is associated with risk of flare-up and disease progression. This hypothesis is based on published studies that show: (1) The circadian rhythm regulates many biological processes including multiple IBD-relevant biological processes that are critical in inflammatory/immune processes such as environment/microbe interaction, microbe/host interaction, intestinal barrier integrity and mucosal immunity-all central in the pathogenesis of IBD, and (2) Circadian machinery is the primary tool for the host to interact with the environment. Circadian misalignment results in a loss of preparedness of the host to respond and adjust to the environmental changes that could make the host more vulnerable to IBD flare-ups. In this review, we first provide an overview of circadian rhythms and its role in healthy and disease states. Then we present data to support our hypothesis that: (1) IBD patients have disrupted circadian rhythms ("social jet lag") and (2) circadian misalignment and associated disrupted sleep decreases the resiliency of IBD patients resulting in microbiota dysbiosis, more disrupted intestinal barrier integrity and a more aggressive disease phenotype. We also show that circadian-directed interventions have a potential to mitigate the deleterious impact of disrupted circadian and improve IBD disease course.

The association between salivary IL-6 and poor sleep quality assessed using Apple watches in stressed workers in Japan

Insomnia is a major concern among stressed workers worldwide. Although stress generally has a detrimental effect on sleep quality, the impact of biological stress, especially the immunological stress response, on sleep quality is not yet fully understood. Stressed workers were recruited through a screening process using a Brief Job Stress Questionnaire. The participants were asked to complete various occupation-related questionnaires. Additionally, saliva samples were collected to assess interleukin-6 (IL-6) levels as an immunological stress response. Subsequently, they were asked to wear an Apple Watch to record their sleep pattern for one week. Their sleep architecture was estimated using a previously published and validated method. Finally, data from 73 participants were analyzed. Our multivariable analysis revealed that shorter durations of slow-wave sleep (non-rapid eye movement sleep stage 3) were significantly associated with elevated IL-6 levels (p = 0.005) and greater daytime sleepiness (p = 0.002) after controlling for total sleep time. Our finding that a higher immunological stress response is associated with poor sleep quality contributes to a better understanding of insomnia in stressed workers and emphasizes the importance of stress management in this population.

Do nocturnal asthma attacks influence sleep parameters and inflammatory markers? A cross-sectional population-based study

PURPOSE

To evaluate the effects of nocturnal asthma on sleep parameters and inflammatory markers according to the severity of the condition in participants in the São Paulo Epidemiologic Sleep Study (EPISONO).

METHODS

Data from the 2007 and 2018 editions of the EPISONO study were utilized. Subjects completed validated sleep and respiratory questionnaires, underwent nocturnal polysomnography and spirometry tests, and provided blood samples for the assessment of inflammatory parameters.

RESULTS

Of 72 participants (67% women), 53% (n = 38) had intermittent nocturnal asthma symptoms and 47% (n = 34) had persistent asthma (mild, moderate, and severe). Individuals with persistent nocturnal symptoms had a higher body mass index (BMI), were more likely to have respiratory symptoms, and had worse lung function, a higher apnea-hypopnea index (AHI), and higher desaturation index than individuals with intermittent nocturnal symptoms. Positive associations were identified between nocturnal asthma and obstructive sleep apnea (OSA). A higher frequency of OSA was observed in participants with persistent asthma and participants with OSA were more likely to have persistent than intermittent asthma. However, there were no significant differences between the immunological parameters of those with intermittent or persistent asthma.

CONCLUSIONS

This study highlights the relevance of nocturnal symptoms as a valuable indicator of asthma severity. The findings also add to the existing body of evidence linking nocturnal asthma and OSA.

Implications of sleep disorders for periodontitis

PURPOSE

Periodontitis is a chronic inflammatory disease caused by multi-factors. Sleep is a natural physiologic process, and the sleep duration, quality, and patterns might be associated with periodontitis. Meanwhile, periodontitis might in turn induce systemic inflammation and thus impact sleep in different ways as well.

METHODS

To investigate the bidirectional relationship between sleep disorder and periodontitis, a literature search was conducted to reveal the interaction and possible mechanism between these two diseases.

RESULTS

The results show that sleep disorders can affect the progression of periodontitis via some pathomechanisms, and periodontitis also has a reverse impact on sleep.

CONCLUSION

Although the epidemiologic and clinical trials found the possible associations between sleep disorder and periodontitis, their relationship is still not that explicit. Further studies are warranted to shed light on them, to improve preventive health care.

Effects of melatonin on postoperative sleep quality: a systematic review, meta-analysis, and trial sequential analysis

PURPOSE

Postoperative sleep disturbances are common. Although several studies have examined the effect of melatonin on postoperative sleep disturbances, the results have not reached any definitive conclusion. We sought to conduct a systematic review to compare the effects of melatonin and melatonin agonists on postoperative sleep quality with those of placebo or no treatment in adult patients who underwent surgery under general or regional anesthesia.

METHODS

We searched MEDLINE, Cochrane Central Register of Controlled Trials, Embase, Web of Science, ClinicalTrials.gov, and the UMIN Clinical Trials Registry up to 18 April 2022. Randomized clinical trials examining the effects of melatonin or melatonin agonists in patients undergoing general or regional anesthesia with sedation for any surgery were eligible for inclusion. The primary outcome was sleep quality measured using a visual analog scale (VAS). The secondary outcomes were postoperative sleep duration, sleepiness, pain, opioid consumption, quality of recovery, and adverse events. A random-effects model was used to combine the results. We assessed study quality with the Cochrane Risk of Bias Tool version 2. We applied a trial sequential analysis to assess the precision of the combined results.

RESULTS

Eight studies (516 participants) were analyzed for sleep quality. Of those, four studies used only a short duration of melatonin, either on the night before and the day of surgery or only on the day of surgery. A random-effects meta-analysis showed that melatonin did not improve sleep quality measured by VAS compared with placebo (mean difference, -0.75 mm; 95% confidence interval, -4.86 to 3.35), with low heterogeneity (I2, 5%). Trial sequential analysis revealed that the accrued information size (n = 516) reached the estimated required information size (n = 295). We downgraded the certainty of the evidence because of the high risk of bias. The effect on postoperative adverse events was comparable between the melatonin and control groups.

CONCLUSION

Our results indicate that melatonin supplementation does not improve postoperative sleep quality measured with the VAS compared with placebo in adult patients (GRADE: moderate).

STUDY REGISTRATION

PROSPERO (CRD42020180167); registered 27 October 2022.

A review of cytokine-based pathophysiology of Long COVID symptoms

The Long COVID/Post Acute Sequelae of COVID-19 (PASC) group includes patients with initial mild-to-moderate symptoms during the acute phase of the illness, in whom recovery is prolonged, or new symptoms are developed over months. Here, we propose a description of the pathophysiology of the Long COVID presentation based on inflammatory cytokine cascades and the p38 MAP kinase signaling pathways that regulate cytokine production. In this model, the SARS-CoV-2 viral infection is hypothesized to trigger a dysregulated peripheral immune system activation with subsequent cytokine release. Chronic low-grade inflammation leads to dysregulated brain microglia with an exaggerated release of central cytokines, producing neuroinflammation. Immunothrombosis linked to chronic inflammation with microclot formation leads to decreased tissue perfusion and ischemia. Intermittent fatigue, Post Exertional Malaise (PEM), CNS symptoms with "brain fog," arthralgias, paresthesias, dysautonomia, and GI and ophthalmic problems can consequently arise as result of the elevated peripheral and central cytokines. There are abundant similarities between symptoms in Long COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). DNA polymorphisms and viral-induced epigenetic changes to cytokine gene expression may lead to chronic inflammation in Long COVID patients, predisposing some to develop autoimmunity, which may be the gateway to ME/CFS.

Louis EK, Przybelski SA, Morgenthaler TI, Machulda MM, Boeve BF, Petersen RC, Jack CR, Graff-Radford J, Vemuri P, Mielke MM. Sleepiness in Cognitively Unimpaired Older Adults Is Associated With CSF Biomarkers of Inflammation and Axonal Integrity

Introduction

Sleepiness has been associated with cognitive decline and dementia in the elderly. Older adults with excessive daytime sleepiness appear to be more vulnerable to longitudinal amyloid PET accumulation before the onset of the dementia. However, it remains unclear whether sleepiness is similarly associated with other biomarkers of Alzheimer's disease (AD), axonal integrity, and inflammation, which may also contribute to neurodegeneration and cognitive decline.

Methods

In this cross-sectional analysis, we identified 260 cognitively unimpaired adults (>60 years) from the Mayo Clinic Study of Aging, a population-based cohort from Olmsted County (MN), who underwent CSF quantification of AD biomarkers (Aβ42, p-tau, p-tau/Aβ42) in addition to at least one of the following biomarkers [neurofilament light chain (NfL) interleukin-6 (IL-6), IL-10, and tumor necrosis factor-α (TNF-α)]. We fit linear regression models to assess associations between sleepiness, as measured by the Epworth Sleepiness Scale (ESS), and CSF biomarkers, controlling for age, sex, APOε4 status, body mass index, hypertension, dyslipidemia, and prior diagnosis of obstructive sleep apnea.

Results

Higher ESS scores were associated with higher CSF IL-6 and NfL, but not with the other CSF biomarkers. For every ESS score point increase, there was a 0.009 ([95% CI 0.001-0.016], p = 0.033) increase in the log of IL-6 and 0.01 ([95% CI 0.002-0.018], p = 0.016) increase in the log of NfL. A sensitivity analysis showed an association between ESS scores and log of p-tau/Aβ42 only in participants with an abnormal ratio (>0.023), highly predictive of amyloid positivity. For every ESS score point increase, there was a 0.006 ([95% CI 0.001-0.012], p = 0.021) increase in the log of CSF p-tau/Aβ42.

Conclusion

Sleepiness was associated with greater CSF IL-6 and NfL levels, which could contribute to neurodegeneration or alternatively cause sleepiness. Higher NfL levels may result from sleep disruption and/or contribute to sleepiness via disturbed connectivity or damage to wake-promoting centers. Associations between sleepiness and p-tau/Aβ42 in participants with abnormal ratio suggest that amyloid positivity contributes to vulnerability to sleep disturbance, which may further amyloid accumulation in a feed-forward loop process. Prospective studies of these markers are needed to determine cause-effect relationships between these associations.

Sleep Disturbance and Alzheimer's Disease: The Glial Connection

Poor quality and quantity of sleep are very common in elderly people throughout the world. Growing evidence has suggested that sleep disturbances could accelerate the process of neurodegeneration. Recent reports have shown a positive correlation between sleep deprivation and amyloid-β (Aβ)/tau aggregation in the brain of Alzheimer's patients. Glial cells have long been implicated in the progression of Alzheimer's disease (AD) and recent findings have also suggested their role in regulating sleep homeostasis. However, how glial cells control the sleep-wake balance and exactly how disturbed sleep may act as a trigger for Alzheimer's or other neurological disorders have recently gotten attention. In an attempt to connect the dots, the present review has highlighted the role of glia-derived sleep regulatory molecules in AD pathogenesis. Role of glia in sleep disturbance and Alzheimer's progression.

Circadian rhythms and cancers: the intrinsic links and therapeutic potentials

The circadian rhythm is an evolutionarily conserved time-keeping system that comprises a wide variety of processes including sleep-wake cycles, eating-fasting cycles, and activity-rest cycles, coordinating the behavior and physiology of all organs for whole-body homeostasis. Acute disruption of circadian rhythm may lead to transient discomfort, whereas long-term irregular circadian rhythm will result in the dysfunction of the organism, therefore increasing the risks of numerous diseases especially cancers. Indeed, both epidemiological and experimental evidence has demonstrated the intrinsic link between dysregulated circadian rhythm and cancer. Accordingly, a rapidly increasing understanding of the molecular mechanisms of circadian rhythms is opening new options for cancer therapy, possibly by modulating the circadian clock. In this review, we first describe the general regulators of circadian rhythms and their functions on cancer. In addition, we provide insights into the mechanisms underlying how several types of disruption of the circadian rhythm (including sleep-wake, eating-fasting, and activity-rest) can drive cancer progression, which may expand our understanding of cancer development from the clock perspective. Moreover, we also summarize the potential applications of modulating circadian rhythms for cancer treatment, which may provide an optional therapeutic strategy for cancer patients.

Fatigue Is Common in Immunoglobulin G Subclass Deficiency and Correlates With Inflammatory Response and Need for Immunoglobulin Replacement Therapy

Purpose

Individuals with immunoglobulin G deficiency (IgGsd) often complain of fatigue. The correlation between systemic inflammation and fatigue is unknown. In this study perceived quality of life (QoL) and fatigue in individuals with IgGsd, on and off immunoglobulin replacement therapy (IgRT) were correlated to inflammatory markers in plasma to identify the subgroup that benefits from IgRT.

Method

Thirty-five IgGsd-patients were sampled on three occasions: at baseline, after being on IgRT for at least 18 months, and 18 months after discontinuation of IgRT. Short form 36, EQ-5D-5L visual analogue scale and fatigue impact scale questionnaires were used for evaluation of QoL and fatigue. Furthermore, a panel of 92 inflammatory markers were analysed in plasma. Thirty-two gender- and age-matched healthy individuals were included as controls and sampled on one occasion.

Results

QoL was lower and perceived fatigue higher in IgGsd compared to the controls. Severe fatigue and low QoL were associated with the need to restart IgRT (which is considered in IgGsd-individuals with a high burden of infections in Sweden). Twenty-five inflammatory factors were dysregulated in IgGsd and the plasma protein patterns were similar regardless of whether IgRT was ongoing or not. Enrichment analysis indicated IL-10 signalling as the most affected pathway. Severe fatigue was associated with decreased levels of the neurotrophic factors VEGFA and CSF-1.

Conclusion

Fatigue is a major contributory factor to impaired health-related QoL in IgGsd and is related to the need for IgRT. Low-grade systemic inflammation is a potential driver of fatigue. In addition to the burden of infections, we suggest the degree of fatigue should be considered when the decision to introduce IgRT is made.

Inflammatory markers in postoperative cognitive dysfunction for patients undergoing total hip arthroplasty: a meta-analysis

BACKGROUND

Postoperative cognitive dysfunction (POCD) is a poorly understood disorder, very common even after total hip arthroplasty (THA). It is widely considered that inflammation response play a role in the pathogenesis of POCD.

AIMS

The aim of the present study was to investigate whether inflammation cytokine concentrations could serve as biomarkers for POCD in patients undergoing THA.

METHODS

A systematic search of databases was conducted to retrieve publications measuring circulating inflammatory markers of patients with and without POCD after THA. Inflammatory markers identified in more than two studies were pooled. The standardized mean difference (SMD) and the 95% confidence interval (95% CI) were calculated for each outcome. Fail-safe N statistics was calculated to estimate possible publication bias.

RESULTS

The pooled incidence rate of POCD after THA by combining 11 cohort studies was 31%. A total of five inflammatory markers, CRP, S-100B, IL-1β, IL-6 and TNF-α, were assessed. Significantly higher pre-operative CRP (P = 0.012) and S-100B (P < 0.0001) as well as post-operative CPR (P = 0.005) and IL-6 (P < 0.0001) at 6 h were found in POCD compared with non-POCD patients undergoing THA. Fail-safe N statistics revealed that these results are robust.

DISCUSSION

The current evidence suggests that some of the inflammatory markers, including CRP, S-100B, and IL-6, were correlated with the occurrence of POCD after THA.

CONCLUSION

Monitor of inflammatory markers might help early diagnosis of POCD after THA and development of preventive strategies.

Pilot Study: Nutritional and Preclinical Safety Investigation of Fermented Hispidin-Enriched Sanghuangporus sanghuang Mycelia: A Promising Functional Food Material to Improve Sleep

Sleep disturbances have been the hallmark of the recent coronavirus disease 2019 pandemic. Studies have shown that once sleep is disrupted, it can lead to psychological and physical health issues which can, in turn, disrupt circadian rhythm and induce further sleep disruption. As consumers are trying to establish healthy routines, nutritional and preclinical safety investigation of fermented hispidin-enriched Sanghuangporus sanghuang mycelia (GKSS) as a novel food material for spontaneous sleep in Sprague-Dawley rats is conducted for the first time. Results showed that the nutritional analysis of GKSS including moisture, ash, crude lipid, crude protein, carbohydrate, and energy were found to be 2.4 ± 0.3%, 8.0 ± 2.5%, 1.7 ± 0.3%, 22.9 ± 1.2%, 65.1 ± 3.1%, and 367.1 ± 10.2 kcal/100 g respectively. In the 28-day repeated-dose oral toxicity study, only Sprague-Dawley male rats receiving 5 g/kg showed a slight decrease in feed consumption at week 3, but no associated clinical signs of toxicity or significant weight loss were observed. Although a significant reduction of the platelet count was found in mid- and high-dose GKSS treated male groups, such changes were noted to be within the normal range and were not correlated with relative spleen weight changes. Hence, the no observed adverse effect level (NOAEL) of GKSS was identified to be higher than 5 g/kg in rats. After the safety of GKSS is confirmed, the sleep-promoting effect of GKSS ethanolic extract enriched with hispidin was further assessed. Despite 75 mg/kg of GKSS ethanolic extract does not affect wakefulness, rapid eye movement (REM) sleep and non-REM (NREM) sleep, GKSS ethanolic extract at 150 mg/kg significantly decreased wakefulness and enhanced NREM and REM sleep. Interestingly, such effects seem to be mediated through anti-inflammatory activities via NF-E2-related factor-2 (Nrf2) signaling pathway. Taken together, these findings provide the preliminary evidence to studies support the claims suggesting that GKSS contained useful phytochemical hispidin could be considered as and is safe to use as a functional food agent or nutraceutical for relieving sleep problems mediated by Nrf2 pathway, which the results are useful for future clinical pilot study.

Gender Differences in the Context of Obstructive Sleep Apnea and Metabolic Diseases

The relationship between obstructive sleep apnea (OSA) and endocrine and metabolic disease is unequivocal. OSA, which is characterized by intermittent hypoxia and sleep fragmentation, leads to and exacerbates obesity, metabolic syndrome, and type 2 diabetes (T2D) as well as endocrine disturbances, such as hypothyroidism and Cushing syndrome, among others. However, this relationship is bidirectional with endocrine and metabolic diseases being considered major risk factors for the development of OSA. For example, polycystic ovary syndrome (PCOS), one of the most common endocrine disorders in women of reproductive age, is significantly associated with OSA in adult patients. Several factors have been postulated to contribute to or be critical in the genesis of dysmetabolic states in OSA including the increase in sympathetic activation, the deregulation of the hypothalamus-pituitary axis, the generation of reactive oxygen species (ROS), insulin resistance, alteration in adipokines levels, and inflammation of the adipose tissue. However, probably the alterations in the hypothalamus-pituitary axis and the altered secretion of hormones from the peripheral endocrine glands could play a major role in the gender differences in the link between OSA-dysmetabolism. In fact, normal sleep is also different between men and women due to the physiologic differences between genders, with sex hormones such as progesterone, androgens, and estrogens, being also connected with breathing pathologies. Moreover, it is very well known that OSA is more prevalent among men than women, however the prevalence in women increases after menopause. At the same time, the step-rise in obesity and its comorbidities goes along with mounting evidence of clinically important sex and gender differences. Metabolic and cardiovascular diseases, seen as a men's illness for decades, presently are more common in women than in men and obesity has a higher association with insulin-resistance-related risk factors in women than in men. In this way, in the present manuscript, we will review the major findings on the overall mechanisms that connect OSA and dysmetabolism giving special attention to the specific regulation of this relationship in each gender. We will also detail the gender-specific effects of hormone replacement therapies on metabolic control and sleep apnea.

Occupational Difference in Association of Poor Sleep Quality and Metabolic Syndrome: Differences between Workers and Employees

Background

Regarding insufficient data about interaction of job in association of sleep quality with metabolic syndrome (MS), this study has been designed to evaluate this association in workers and employees.

Methods

This cross-sectional study was conducted on 448 municipal staff (employee group: N = 295; worker group: N = 153) referring for periodic examinations. The relationship between sleep quality and MS and their relevant components was investigated in both groups.

Results

In the worker group, poor sleep quality was independently associated with the risk of MS by 3.04 times (P < 0.01). Among the components of metabolic syndrome, hypertriglyceridemia was associated with a greater number of sleep disorder components. There was no association between metabolic syndrome and sleep quality in the employee group.

Conclusion

Poor sleep quality exerts different effects on metabolic complications in employees and workers.

Inflammation, hippocampal volume, and cognition in schizophrenia: results from the Northern Finland Birth Cohort 1966

Increased blood interleukin-6 (IL-6) levels are a replicated abnormality in schizophrenia, and may be associated with smaller hippocampal volumes and greater cognitive impairment. These findings have not been investigated in a population-based birth cohort. The general population Northern Finland Birth Cohort 1966 was followed until age 43. Subjects with schizophrenia were identified through the national Finnish Care Register. Blood IL-6 levels were measured in n = 82 subjects with schizophrenia and n = 5373 controls at age 31. Additionally, 31 patients with schizophrenia and 63 healthy controls underwent brain structural MRI at age 34, and cognitive testing at ages 34 and 43. Patients with schizophrenia had significantly higher median (interquartile range) blood IL-6 levels than controls (5.31, 0.85-17.20, versus 2.42, 0.54-9.36, p = 0.02) after controlling for potential confounding factors. In both schizophrenia and controls, higher blood IL-6 levels were predictors of smaller hippocampal volumes, but not cognitive performance at age 34. We found evidence for increased IL-6 levels in patients with midlife schizophrenia from a population-based birth cohort, and replicated associations between IL-6 levels and hippocampal volumes. Our results complement and extend the previous findings, providing additional evidence that IL-6 may play a role in the pathophysiology of schizophrenia and associated brain alterations.

Are Anti-Inflammatory Cytokines Associated with Cognitive Impairment in Patients with Insomnia Comorbid with Depression? A Pilot Study

BACKGROUND

To distinguish insomnia comorbid with depression (ICD) from chronic insomnia disorder (CID) by exploring the relationship between serum levels of frequently overlooked anti-inflammatory cytokines and cognitive function.

METHODS

A total of 42 ICD patients, 63 CID patients, and 42 healthy control subjects were enrolled in the study. The Pittsburgh Sleep Quality Index and Hamilton Depression Rating Scale were used to assess sleep quality and depression severity, respectively. The Chinese-Beijing version of Montreal Cognitive Assessment scale (MoCA-C) and Nine-Box Maze Test (NBMT) were used to assess cognitive function. Serum levels of anti-inflammatory interleukins (IL-1RA, IL-4, IL-5, IL-10, IL-13, and IL-28A), transforming growth factor (TGF)-β1, granulocyte-macrophage colony-stimulating factor, interferon-γ, and the chemokine regulated upon activation, normal T cell expressed and secreted (RANTES) were measured by enzyme-linked immunosorbent assay.

RESULTS

The ICD group had significantly more errors in the spatial reference task (H=2.55, P_s=0.03) and spatial working memory task (H=5.67, P_s<0.01) of the NBMT, as well as lower levels of IL-1RA (H=-2.85, P_s=0.01), IL-4 (H=-3.28, P_s<0.01), IL-5 (H=-3.35, P_s<0.01), IL-10 (H=-4.46, P_s<0.01), and IL-28A (H=-2.75, P_s=0.02) than control subjects. Compared with the CID group, the ICD group had significantly more errors in the spatial reference memory task (H=-2.84, P_s=0.01) of the NBMT, and lower levels of IL-5 (H=3.41, P_s<0.01), IL-10 (H=5.30, P_s<0.01), IL-13 (H=3.89, P_s<0.01), and GM-CSF (H=2.72, P_s=0.02). A partial correlation analysis showed that the level of one or more of IL-4, IL-5, IL-10, IL-13, and TGF-β1 was positively correlated with cognitive function (MoCA-C score and/or performance in spatial memory task) in ICD patients.

CONCLUSION

ICD is a distinct condition that can be distinguished from CID based on immune dysfunction and specific types of cognitive dysfunction.

Understanding the Role of Interleukin-6 (IL-6) in the Joint and Beyond: A Comprehensive Review of IL-6 Inhibition for the Management of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic, debilitating autoimmune disorder involving inflammation and progressive destruction of the joints, affecting up to 1% of the population. The majority of patients with RA have one or more comorbid conditions, the most common being cardiovascular disease, osteoporosis, and depression, the presence of which are associated with poorer clinical outcomes and lower health-related quality of life. RA pathogenesis is driven by a complex network of proinflammatory cells and cytokines, and of these, interleukin-6 (IL-6) plays a key role in the chronic inflammation associated with RA. Through cell signaling that can be initiated by both membrane-bound and soluble forms of its receptor, IL-6 acts both locally to promote joint inflammation and destruction, and in the circulation to mediate extra-articular manifestations of RA, including pain, fatigue, morning stiffness, anemia, and weight loss. This narrative review describes the role of IL-6 in the pathogenesis of RA, its comorbidities, and extra-articular systemic manifestations, and examines the effects of the IL-6 receptor inhibitors sarilumab and tocilizumab on clinical endpoints of RA, patient-reported outcomes, and common comorbidities and extra-articular manifestations.

Sleep as a Novel Biomarker and a Promising Therapeutic Target for Cerebral Small Vessel Disease: A Review Focusing on Alzheimer's Disease and the Blood-Brain Barrier

Cerebral small vessel disease (CSVD) is a leading cause of cognitive decline in elderly people and development of Alzheimer’s disease (AD). Blood–brain barrier (BBB) leakage is a key pathophysiological mechanism of amyloidal CSVD. Sleep plays a crucial role in keeping health of the central nervous system and in resistance to CSVD. The deficit of sleep contributes to accumulation of metabolites and toxins such as beta-amyloid in the brain and can lead to BBB disruption. Currently, sleep is considered as an important informative platform for diagnosis and therapy of AD. However, there are no effective methods for extracting of diagnostic information from sleep characteristics. In this review, we show strong evidence that slow wave activity (SWA) (0–0.5 Hz) during deep sleep reflects glymphatic pathology, the BBB leakage and memory deficit in AD. We also discuss that diagnostic and therapeutic targeting of SWA in AD might lead to be a novel era in effective therapy of AD. Moreover, we demonstrate that SWA can be pioneering non-invasive and bed–side technology for express diagnosis of the BBB permeability. Finally, we review the novel data about the methods of detection and enhancement of SWA that can be biomarker and a promising therapy of amyloidal CSVD and CSVD associated with the BBB disorders.

Electroacupuncture: A New Approach for Improved Postoperative Sleep Quality After General Anesthesia

General anesthesia produces a state of drug-induced unconsciousness that is controlled by the extent and duration of administered agents. Whether inhalation or intravenous in formulation, such agents may interfere with normal sleep-wake cycles, impairing postoperative sleep quality and creating complications. Electroacupuncture is a new approach widely applied in clinical practice during recent years. This particular technology helps regulate neurotransmitter concentrations in the brain, lowering norepinephrine and dopamine levels to improve sleep quality. It also alleviates surgical pain that degrades postoperative sleep quality after general anesthesia by downregulating immune activity (SP, NK-1, and COX-1) and upregulating serotonin receptor (5-HT1AR, 5-HT2AR) and endocannabinoid expression levels. However, large-scale, multicenter studies are still needed to determine the optimal duration, frequency, and timing of electroacupuncture for such use.

Study protocol for a randomised controlled trial evaluating the effects of the orexin receptor antagonist suvorexant on sleep architecture and delirium in the intensive care unit

INTRODUCTION

Insomnia frequently occurs in patients admitted to an intensive care unit (ICU). Sleep-promoting agents may reduce rapid eye movement sleep and have deliriogenic effects. Suvorexant (Belsomra) is an orexin receptor antagonist with Food and Drug Administration (FDA) approval for the treatment of adult insomnia, which improves sleep onset and maintenance as well as subjective measures of quality of sleep. This trial will evaluate the efficacy of postoperative oral suvorexant treatment on night-time wakefulness after persistent sleep onset as well as the incidence and duration of delirium among adult cardiac surgical patients.

METHODS AND ANALYSIS

In this single-centre, randomised, double-blind, placebo-controlled trial, we will enrol 120 patients, aged 60 years or older, undergoing elective cardiac surgery with planned postoperative admission to the ICU. Participants will be randomised to receive oral suvorexant (20 mg) or placebo one time a day starting the night after extubation. The primary outcome will be wakefulness after persistent sleep onset. The secondary outcome will be total sleep time. Exploratory outcomes will include time to sleep onset, incidence of postoperative in-hospital delirium, number of delirium-free days and subjective sleep quality.

ETHICS AND DISSEMINATION

Ethics approval was obtained through the 'Committee on Clinical Investigations' at Beth Israel Deaconess Medical Center (protocol number 2019P000759). The findings will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

This trial has been registered at clinicaltrials.gov on 17 September 2019 (NCT04092894).

Interleukin-2 drives cortisol secretion in an age-, dose-, and body composition-dependent way

BACKGROUND

Interleukin-2 (IL-2), one of the proinflammatory cytokines, is used in the treatment of certain malignancies. In some studies, transient increases in cortisol and ACTH secretion occurred. Thus, this agent may be used as an experimental probe of adrenal cortisol secretion.

OBJECTIVE

This study quantifies the effects of low and moderate doses of IL-2 on cortisol secretion and assesses the modulation by age, dose and body composition.

SITE

Mayo Clinical Translational Research Unit.

SUBJECTS

Study comprised 35 healthy men, 17 young and 18 older.

METHODS

Randomized prospective double-blind saline-controlled study of IL-2 administration in two doses with concurrent 10-min blood sampling for 24 h.

OUTCOME MEASURES

Deconvolution analysis and approximate entropy of cortisol secretion.

RESULTS

Low-dose IL-2 administration increased nocturnal pulsatile cortisol secretion from 1460 ± 160 to 2120 ± 220 nmol/L/8 h in young subjects and from 1680 ± 105 to 1960 ± 125 nmol/L/8 h (treatment P < 0.0001, but more in young than older, P = 0.02). Comparable results were obtained for total cortisol secretion (P treatment <0.0001, age effect P = 0.005). The higher IL-2 dose caused a large increase in young (P < 0.0001), but not in older (P = 0.90) subjects. This dose also increased approximate entropy from 0.877 ± 0.041 to 1.024 ± 0.049 (P = 0.008), pointing to reduced secretory orderliness. Incremental cortisol (nocturnal) secretion correlated negatively with visceral fat mass (R = -0.41, P = 0.019).

CONCLUSION

In healthy men, IL-2 injection drives pulsatile cortisol secretion in a dose-dependent way in young, but not older, individuals and erodes cortisol secretory orderliness at a higher dose in young subjects. Cortisol responses are diminished with increasing abdominal visceral fat mass.

Psychologic stress and disease activity in patients with inflammatory bowel disease: A multicenter cross-sectional study

Background and aims

Psychologic stress can affect the pathogenesis of inflammatory bowel disease (IBD), but the precise contribution of psychologic stress to IBD remains unclear. We investigated the association of psychologic stress with disease activity in patients with IBD, especially in terms of mental state and sleep condition.

Methods

This was a multi-center observational study comprising 20 institutions. Data were collected using survey forms for doctors and questionnaires for patients, and the association of psychologic stress with clinical parameters was investigated. Mental state was evaluated using the Center for Epidemiologic Studies Depression (CES-D) scale, and sleep condition was evaluated by querying patients about the severity of insomnia symptoms.

Results

A total of 1078 IBD patients were enrolled, including 303 patients with Crohn’s disease and 775 patients with ulcerative colitis. Seventy-five percent of IBD patients believed that psychologic stress triggered an exacerbation of their disease (PSTE group) and 25% did not (non-PSTE group). The CES-D scores were significantly higher for patients with clinically active disease than for those in remission in the PSTE group (median (interquartile range) = 7 (4–9.5) vs. 5 (3–7), p < .0001), but not in the non-PSTE group (5 (2–8) vs. 4 (3–7), p = 0.78). Female sex and disease exacerbation by factors other than psychologic stress were independent factors of psychologic stress-triggered disease exacerbation. Also, patients with insomnia had higher disease activity than those without insomnia, especially in the PSTE group.

Conclusions

A worsened mental state correlates with disease activity in IBD patients, especially those who believe that their disease is exacerbated by psychologic stress.

Postoperative 24-h Acute Sleep Deprivation Improves Learning and Memory Through Inhibition of Tau Phosphorylation in the Hippocampal Neurons of Splenectomized Rats

PURPOSE

As tau pathology is involved in impaired postoperative learning and memory in rats, we attempted to identify the possible mechanisms by which tau pathology affects postoperative sleep deprivation.

METHODS

Adult male Sprague-Dawley rats were randomly assigned into six groups as follows: the Control group, Anaesthesia group, Surgery group, Sleep deprivation (SD) group: 24-h SD with the modified multiple platform method (MMPM), Anaesthesia and SD (ASD) group, and Surgery and SD (SSD) group. Tau396 and FOXQ1 protein expression levels in the hippocampal neurons of all groups were analysed. Changes following co-culture of hippocampal neurons with IL-6 were detected by flow cytometry.

RESULTS

Twenty-four hours of acute SD decreased the error scores on postoperative day 5 in the ASD and SSD groups compared with the Anaesthesia and Surgery groups. Compared with the tau levels in the Control group, tau levels in the Anaesthesia and Surgery groups were increased, but SD decreased the expression of tau in the ASD and SSD groups. The expression levels of tau and FOXQ1 were inversely regulated. When hippocampal neurons were co-cultured with IL-6, the same changes were observed.

CONCLUSION

Postoperative 24-h acute SD improves learning and memory through inhibition of tau phosphorylation and increases IL-6-induced expression of FOXQ1 in the hippocampal neurons of splenectomized rats.

Molecular Mechanisms of Cancer-Induced Sleep Disruption

Sleep is essential for health. Indeed, poor sleep is consistently linked to the development of systemic disease, including depression, metabolic syndrome, and cognitive impairments. Further evidence has accumulated suggesting the role of sleep in cancer initiation and progression (primarily breast cancer). Indeed, patients with cancer and cancer survivors frequently experience poor sleep, manifesting as insomnia, circadian misalignment, hypersomnia, somnolence syndrome, hot flushes, and nightmares. These problems are associated with a reduction in the patients' quality of life and increased mortality. Due to the heterogeneity among cancers, treatment regimens, patient populations and lifestyle factors, the etiology of cancer-induced sleep disruption is largely unknown. Here, we discuss recent advances in understanding the pathways linking cancer and the brain and how this leads to altered sleep patterns. We describe a conceptual framework where tumors disrupt normal homeostatic processes, resulting in aberrant changes in physiology and behavior that are detrimental to health. Finally, we discuss how this knowledge can be leveraged to develop novel therapeutic approaches for cancer-associated sleep disruption, with special emphasis on host-tumor interactions.

Neuroendocrine and neurophysiological effects of interleukin 6 in rheumatoid arthritis

RA is a chronic, systemic, autoimmune disease characterized by inflammation and degradation of the joints, causing significant negative impact on quality of life. In addition to joint disease, symptoms and co-morbidities associated with RA-namely pain, fatigue and mood disorders-are often as debilitating as the disease itself. The pro-inflammatory cytokine IL-6 plays a critical role in RA-associated pathology. However, a greater understanding of the translational effects of IL-6 outside of the immune system is needed. This review discusses our current understanding of emerging aspects of IL-6 in RA-associated pain, fatigue and mood disorders such as depression and anxiety. This review also describes the clinical effects of IL-6 inhibition on these symptoms and co-morbidities in patients with RA.

Inflammation- and angiogenesis-related biomarkers are correlated with cancer-related fatigue in colorectal cancer patients: Results from the ColoCare Study

Cancer-related fatigue is one of the most common side effects of colorectal cancer treatment and is affected by biomedical factors. We investigated the association of inflammation- and angiogenesis-related biomarkers with cancer-related fatigue. Pre-surgery (baseline) serum samples were obtained from n = 236 newly diagnosed colorectal cancer patients. Meso Scale Discovery assays were performed to measure levels of biomarkers for inflammation and angiogenesis (CRP, SAA, IL-6, IL-8, MCP-1, sICAM-1, sVCAM-1, TNFα, VEGFA and VEGFD). Cancer-related fatigue was assessed with the EORTC QLQ-30 questionnaire at baseline and 6 and 12 months post-surgery. We tested associations using Spearman's partial correlations and logistic regression analyses, adjusting for age, sex and body mass index. sICAM-1 and VEGFD showed a significant positive correlation with cancer-related fatigue at baseline and 6-, and 12-month follow-up (sICAM-1: r = 0.19, p = 0.010; r = 0.24, p = 0.004; r = 0.25, p = 0.006; VEGFD: r = 0.20, p = 0.006; r = 0.15, p = 0.06; r = 0.23, p = 0.01 respectively). Biomarkers of inflammation and angiogenesis measured prior to surgery are associated with cancer-related fatigue in colorectal cancer patients throughout various time points. Our results suggest the involvement of overexpressed sICAM-1 and VEGFD in the development of fatigue.

Health-related quality of life in patients with giant cell arteritis treated with tocilizumab in a phase 3 randomised controlled trial

Background

Patients with giant cell arteritis (GCA) treated with tocilizumab (TCZ) every week or every other week and prednisone tapering achieved superior rates of sustained remission to patients treated with placebo and prednisone tapering in a randomised controlled trial. Health-related quality of life (HRQOL) in patients from this trial is now reported.

Methods

Exploratory analyses of SF-36 PCS and MCS and domain scores, PtGA and FACIT-Fatigue were performed in patients treated with weekly subcutaneous TCZ 162 mg plus 26-week prednisone taper (TCZ-QW + Pred-26) or placebo plus 26-week or 52-week prednisone tapers (PBO + Pred-26 or PBO + Pred-52). These analyses were performed on responder and non-responder patients, including those who achieved the primary outcome and those who experienced flare and received escape prednisone doses.

Results

Baseline SF-36 PCS, MCS and domain scores were low, indicating impaired HRQOL related to GCA. At week 52, least squares mean (LSM) changes in PCS scores improved with TCZ-QW + Pred-26 but worsened in both PBO + Pred groups (p <  0.001). LSM changes in MCS scores increased with TCZ-QW + Pred-26 versus PBO + Pred-52 (p < 0.001). Treatment with TCZ-QW + Pred-26 resulted in significantly greater improvement in four of eight SF-36 domains compared with PBO + Pred-26 and six of eight domains compared with PBO + Pred-52 (p < 0.01). Improvement with TCZ-QW + Pred-26 met or exceeded minimum clinically important differences (MCID) in all eight domains compared with five domains with PBO + Pred-26 and none with PBO + Pred-52. Domain scores in the TCZ-QW + Pred-26 group at week 52 met or exceeded age- and gender-matched normative values (A/G norms). LSM changes from baseline in FACIT-Fatigue scores increased significantly with TCZ-QW + Pred-26, exceeding MCID and A/G norms (p < 0.001).

Conclusions

Patients with GCA receiving TCZ-QW + Pred-26 reported statistically significant and clinically meaningful improvement in SF-36 and FACIT-Fatigue scores compared with those receiving prednisone only. Improvements in the TCZ-QW + Pred-26 group led to recovery of HRQOL to levels at least comparable to those of A/G-matched normative values at week 52 and exceeded normative values in five of eight domains.

Trial registration

ClinicalTrials.gov, NCT01791153. Date of registration: February 13, 2013.

Non-restorative Sleep Caused by Autonomic and Electroencephalography Parameter Dysfunction Leads to Subjective Fatigue at Wake Time in Shift Workers

Sleep is a physiological state that plays important role in the recovery of fatigue. However, the relationship between the physiological status of sleep and subjective fatigue remains unknown. In the present study, we hypothesized that the non-recovery of fatigue at wake time due to non-restorative sleep might be ascribed to changes in specific parameters of electroencephalography (EEG) and heart rate variability (HRV) in poor sleepers. Twenty healthy female shift-working nurses participated in the study. Subjective fatigue was assessed using the visual analog scale (VAS) at bedtime and wake time. During sleep on the night between 2 consecutive day shifts, the EEG powers at the frontal pole, HRV based on electrocardiograms, and distal-proximal gradient of skin temperature were recorded and analyzed. The results indicated that the subjects with high fatigue on the VAS at wake time exhibited (1) a decrease in deep non-rapid eye movement (NREM) (stageN3) sleep duration in the first sleep cycle; (2) a decrease in REM latency; (3) a decrease in ultra-slow and delta EEG powers, particularly from 30 to 65 min after sleep onset; (4) a decrease in the total power of HRV, particularly from 0 to 30 min after sleep onset; (5) an increase in the very low frequency component of HRV; and (6) a smaller increase in the distal-proximal gradient of skin temperature, than those of the subjects with low fatigue levels. The correlational and structural equation modeling analyses of these parameters suggested that an initial decrease in the total power of HRV from 0 to 30 min after sleep onset might inhibit the recovery from fatigue during sleep (i.e., increase the VAS score at wake time) via its effects on the ultra-slow and delta powers from 30 to 65 min after sleep onset, stageN3 duration in the first sleep cycle, REM latency, and distal-proximal gradient of skin temperature. These findings suggest an important role of these physiological factors in recovery from fatigue during sleep, and that interventions to modify these physiological factors might ameliorate fatigue at wake time.

Sarilumab: patient-reported outcomes in rheumatoid arthritis

In the last few decades, strategies for the management of rheumatoid arthritis (RA) have been increasingly oriented toward more comprehensive control of the disease, taking into account even RA extra-articular manifestations, comorbidities, and the patient’s perception about the disease. The need for improving the shared decision-making process suggested by European League Against Rheumatism recommendations is leading to an increasing interest in the role of patient-reported outcomes (PROs) beside the usual more objective criteria for defining clinical response based on disease-activity composite indices. Measurement of such PROs as pain or fatigue may be significantly influenced by mood disorders often complicating RA, the pathogenesis of which is deeply interconnected with phlogistic processes mediated by proinflammatory cytokines. IL6 is a pleiotropic mediator involved in neuroendocrine and neuropsychological processes, besides its well known effects on immune, cardiovascular, and metabolic systems. Therefore, there is a growing body of evidence about the efficacy of IL6 blockade in PRO improvement in RA patients. Sarilumab is a monoclonal antibody binding both soluble and membrane-bound IL6Rα, inhibiting the IL6-mediated signaling pathway with favorable efficacy and safety profile. This review analyzes the importance of PROs in strategies for the management of RA and the pathogenic mechanisms linking IL6 with the patient’s perception of the disease. Moreover, the main findings from sarilumab randomized controlled trials are summarized in detail, emphasizing the potential role of this IL6 blocker in the holistic treatment of RA.

Age modification of the relationship between C-reactive protein and fatigue: findings from Understanding Society (UKHLS)

BACKGROUND

Systemic inflammation may play a role in the development of idiopathic fatigue, that is, fatigue not explained by infections or diagnosed chronic illness, but this relationship has never been investigated in community studies including the entire adult age span. We examine the association of the inflammatory marker C-reactive protein (CRP) and fatigue assessed annually in a 3-year outcome period for UK adults aged 16-98.

METHODS

Multilevel models were used to track fatigue 7, 19, and 31 months after CRP measurement, in 10 606 UK individuals. Models accounted for baseline fatigue, demographics, health conditions diagnosed at baseline and during follow-up, adiposity, and psychological distress. Sensitivity analyses considered factors including smoking, sub-clinical disease (blood pressure, anaemia, glycated haemoglobin), medications, ethnicity, and alcohol consumption.

RESULTS

Fatigue and CRP increased with age, and women had higher values than men. CRP was associated with future self-reported fatigue, but only for the oldest participants. Thus, in those aged 61-98 years, high CRP (>3 mg/L) independently predicted greater fatigue 7, 19, and 31 months after CRP measurement [odds ratio for new-onset fatigue after 7 months: 1.88, 95% confidence interval (CI) 1.21-2.92; 19 months: 2.25, CI 1.46-3.49; 31 months: 1.65, CI 1.07-2.54]. No significant longitudinal associations were seen for younger participants.

CONCLUSIONS

Our findings support previously described CRP-fatigue associations in older individuals. However, there are clear age modifications in these associations, which may reflect a contribution of unmeasured sub-clinical disease of limited relevance to younger individuals. Further work is necessary to clarify intervening processes linking CRP and fatigue in older individuals.

Neuroinflammation, cortical activity, and fatiguing behaviour during self-paced exercise

The present study aimed to identify whether or not the release of interleukin (IL)-6 and soluble (s) IL-6 receptor (R) is associated with fatiguing behaviour and changes in cortical activity during self-paced exercise. Relationships between the IL-6 and its soluble receptors, total work, reductions in power output, and changes in slow, alpha (α) and fast, beta (β) brain waves during self-paced exercise were evaluated. Different intensities and environments were used to manipulate the release of IL-6, whereby seven active males cycled for 60 min in heat stress (HS) or thermoneutral (TN) environments at a clamped rating of perceived exertion (RPE) equating to low intensity (RPE = 12) or high intensity (RPE = 16). IL-6 and sIL-6R were positively associated with total work, but not with reductions in power output. There was greater α activity in high-intensity conditions, which was associated with the reduction in power output. Both high-intensity conditions appeared to have greater β activity, and there was a positive correlation between β activity and total work and β activity and sIL-6R. We conclude that IL-6 and sIL-6R may contribute to perturbations in cortical activity and are associated with total work output, but reductions in power output are likely influenced greater by other internal and external factors.

The role of sleep in pemphigus: a review of mechanisms and perspectives

Pemphigus is an autoimmune bullous disease that causes the development of blisters and erosions on the skin and/or mucosa. Its inflammatory process is mediated by cytokines, which interact with sleep in a bidirectional manner. Pain, a frequent symptom due to pemphigus lesions, is well known to impair sleep quality. Depression is also associated with pemphigus and pro-inflammatory cytokines and may impair sleep. Additionally, a common relationship among other dermatological diseases and sleep has increasingly been described. Poor sleep quality is associated with an increased risk for autoimmune diseases, and insomnia is a comorbidity that has recently been associated with pemphigus. Thus, this review will explore the evidence supporting the likely bidirectional relationship between pemphigus and sleep quality and its possible mechanisms involved. This approach covering both pemphigus and sleep will open a research avenue for future studies focusing on the efficacy of the sleep disorders treatment in patients with pemphigus. In the long term, this may provide relevant information to dermatologists regarding new strategies for the management of pemphigus clinical condition, allowing possibly a better quality of life for the patients.

Antifatigue Effect of Luteolin-6-C-Neohesperidoside on Oxidative Stress Injury Induced by Forced Swimming of Rats through Modulation of Nrf2/ARE Signaling Pathways

Luteolin-6-C-neohesperidoside (LN) is a flavonoid isolated from moso bamboo leaf. This study was performed to evaluate the antifatigue effect of LN on a rat model undergoing the weight-loaded forced swimming test (FST). Briefly, male Sprague-Dawley rats (20-22 weeks old) were forced to undertake exhaustive swimming every other day for 3 weeks. Each swimming session was followed by the administration of distilled water, LN (25-75 mg/kg), or ascorbic acid (100 mg/kg) 1 h later. Oral administration of LN significantly improved exercise endurance; normalized alterations in energy metabolic markers; and decreased serum lactic acid, lactate dehydrogenase, and blood urea nitrogen levels of rats that underwent FST. Moreover, LN enhanced the activities of antioxidant enzymes and antioxidant capacity, as measured by enzyme activity assays, RT-PCR, and Western blotting, as well as decreasing the levels of proinflammatory cytokines such as tumor necrosis factor-α, interleukin-1β (IL-1β), and IL-6 and increasing the level of anti-inflammatory (IL-10) in the liver and skeletal muscle. These results suggested that LN reduces both physical and mental effects of chronic fatigue, probably by attenuating oxidative stress injury and inflammatory responses in the liver and skeletal muscle. This study thus supports the use of LN in functional foods for antifatigue and antioxidant effects.

The role of the brown adipose tissue in β3-adrenergic receptor activation-induced sleep, metabolic and feeding responses

Brown adipose tissue (BAT) is regulated by the sympathetic nervous system via β3-adrenergic receptors (β3-AR). Here we tested the hypothesis that pharmacological stimulation of β3-ARs leads to increased sleep in mice and if this change is BAT dependent. In wild-type (WT) animals, administration of CL-316,243, a selective β3-AR agonist, induced significant increases in non-rapid-eye movement sleep (NREMS) lasting for 4–10 h. Simultaneously, electroencephalographic slow-wave activity (SWA) was significantly decreased and body temperature was increased with a delay of 5–6 h. In uncoupling protein 1 (UCP-1) knockout mice, the middle and highest doses of the β3-AR agonist increased sleep and suppressed SWA, however, these effects were significantly attenuated and shorter-lasting as compared to WT animals. To determine if somnogenic signals arising from BAT in response to β3-AR stimulation are mediated by the sensory afferents of BAT, we tested the effects of CL-316,243 in mice with the chemical deafferentation of the intra-scapular BAT pads. Sleep responses to CL-316,243 were attenuated by ~50% in intra-BAT capsaicin-treated mice. Present findings indicate that the activation of BAT via β3-AR leads to increased sleep in mice and that this effect is dependent on the presence of UCP-1 protein and sleep responses require the intact sensory innervation of BAT.

Sleep disruption in chronic rhinosinusitis

INTRODUCTION

Chronic rhinosinusitis (CRS) is a common disease of the upper airways and paranasal sinuses with a marked decline in quality of life (QOL). CRS patients suffer from sleep disruption at a significantly higher proportion (60 to 75%) than in the general population (8-18 %). Sleep disruption in CRS causes decreased QOL and is linked to poor functional outcomes such as impaired cognitive function and depression. Areas covered: A systematic PubMed/Medline search was done to assess the results of studies that have investigated sleep and sleep disturbances in CRS. Expert commentary: These studies reported sleep disruption in most CRS patients. The main risk factors for sleep disruption in CRS include allergic rhinitis, smoking, and high SNOT-22 total scores. The literature is inconsistent with regard to the prevalence of sleep-related disordered breathing (e.g. obstructive sleep apnea) in CRS patients. Although nasal obstruction is linked to sleep disruption, the extent of sleep disruption in CRS seems to expand beyond that expected from physical blockage of the upper airways alone. Despite the high prevalence of sleep disruption in CRS, and its detrimental effects on QOL, the literature contains a paucity of studies that have investigated the mechanisms underlying this major problem in CRS.

Microarrays-Enabled Hypothesis Generation: The Suspect Role of FNBP-1 in Neuropsychiatric Pathogenesis Associated with HIV and/or HCV Infection

OBJECTIVE

The spectrum of neuropsychiatric illness (NI) associated with the Human Immunodeficiency Virus (HIV) and/or the Hepatitis C Virus (HCV) is far reaching and significantly impacts the clinical presentation and outcome of infected persons; however, the etiological and pathophysiological background remains partially understood. The present work was aimed to investigate the potential significance of formin binding protein 1 (FNBP-1)-dependent pathways in NI-pathogenesis by elaborating on previous microarray-based research in HIV and/or HCV-infected patients receiving interferon-α (IFN-α) immunotherapy via a rigorous data mining procedure.

METHODS

Using microarray data of peripheral whole blood (PB) samples obtained from HCV mono-infected persons (n=25, Affymetrix® HG-U133A_2) 12 h before and after the 1st dose of pegylated IFN-α (PegIFN-α), we re-applied the same analytical algorithm that we had developed and published in an earlier study with HIV/HCV co-infected subjects (N=28, Affymetrix® HG-U133A), in order to evaluate reproducibility of potential NI-related molecular findings in an independent cohort.

RESULTS

Among 28 gene expression profiles (HIV/HCV: N=9 vs. HCV: N=19) selected by applying different thresholds (a Mean Fold Difference value (MFD) in gene expression of ≥ 0.38 (log2) and/or P value from <0.05 to ≤ 0.1) FNBP-1 was identified as the only overlapping marker, which also exhibited a consistent upregulation in association with the development of NI in both cohorts. Previous functional annotation analysis had classified FNBP-1 as molecule with significant enrichment in various brain tissues (P<0.01).

CONCLUSION

Our current findings are strongly arguing for intensifying research into the FNBP-1-related mechanisms that may be conferring risk for or resistance to HIV- and/or HCV-related NI.

Diurnal Variation of Circulating Interleukin-6 in Humans: A Meta-Analysis

The pleiotropic cytokine interleukin-6 (IL-6) has been proposed to contribute to circadian regulation of sleepiness by increasing in the blood at night. Earlier studies have reported diurnal variation of IL-6, but phase estimates are conflicting. We have therefore performed a meta-analysis on the diurnal variation of circulating IL-6. Studies were included if they reported IL-6 in plasma or serum recorded at least twice within 24 hours in the same individual. A systematic search resulted in the inclusion of 43 studies with 56 datasets, for a total of 1100 participants. Individual participant data were available from 4 datasets with a total of 56 participants. Mixed-effects meta-regression modelling confirmed that IL-6 varied across the day, the most conspicuous effect being a trough in the morning. These results stand in contrast to earlier findings of a peak in the evening or night, and suggest that diurnal variation should be taken into account in order to avoid confounding by time of day in studies of IL-6 in plasma or serum.

Prevalence and factors associated with disturbed sleep in patients with ankylosing spondylitis and non-radiographic axial spondyloarthritis: a systematic review

This review explores the prevalence and factors associated with disturbed sleep for patients with ankylosing spondylitis and non-radiographic axial spondyloarthritis in order to clarify consistent findings in this otherwise disparate research field. The association of physical, demographic and psychological factors correlating with poor sleep was explored, and the effectiveness of interventions assessed. Ten electronic databases were searched: AMED, CINAHL, Embase, Medline, PsycINFO, PubMed, Scopus, Web of Science, OpenGrey and BASE. Following application of inclusion and exclusion criteria, 29 articles were critically assessed on the basis of methodology, experimental design, ethics and quality of sleep data, leading to the selection of 15 studies for final review. Poor sleep was reported in 35-90% of patients with axial spondyloarthritis and is more prevalent within this clinical population compared to healthy control subjects. Disturbed sleep is an important aspect of disease for patients and reflects the severity of disease activity, pain, fatigue and functional disability. However, the direction of this relationship is undetermined. Associations with age, gender, years spent in education, quality of life and depression have also been demonstrated. Anti-TNF medication is effective in reducing poor sleep, and exercise has also produced beneficial results. Future research into poor sleep should take account of its multifactorial nature. There is also a current lack of research investigating non-pharmacological interventions or combination therapies. A standardised, validated measurement of poor sleep, appropriate for regular patient screening, would be a useful first step for future research.

Factors associated with experience of fatigue, and functional limitations due to fatigue in patients with stable COPD

BACKGROUND

The aim of this study was to determine the influence of selected physiological, psychological and situational factors on experience of fatigue, and functional limitations due to fatigue in patients with stable chronic obstructive pulmonary disease (COPD).

METHODS

In total 101 patients with COPD and 34 control patients were assessed for experience of fatigue, functional limitation due to fatigue (Fatigue Impact Scale), physiological [lung function, 6-minute walk distance (6MWD), body mass index (BMI), dyspnoea, interleukin (IL)-6, IL-8, high sensitivity C-reactive protein (hs-CRP), surfactant protein D], psychological (anxiety, depression, insomnia), situational variables (age, sex, smoking, living alone, education), and quality of life.

RESULTS

Fatigue was more common in patients with COPD than in control patients (72% versus 56%, p < 0.001). Patients with COPD and fatigue had lower lung function, shorter 6MWD, more dyspnoea, anxiety and depressive symptoms, and worse health status compared with patients without fatigue (all p < 0.01). No differences were found for markers of systemic inflammation. In logistic regression, experience of fatigue was associated with depression [odds ratio (OR) 1.69, 95% confidence interval (CI) 1.28-2.25) and insomnia (OR 1.75, 95% CI 1.19-2.54). In linear regression models, depression, surfactant protein D and dyspnoea explained 35% (R(2)) of the variation in physical impact of fatigue. Current smoking and depression explained 33% (R(2)) of the cognitive impact of fatigue. Depression and surfactant protein D explained 48% (R(2)) of the psychosocial impact of fatigue.

CONCLUSIONS

Experiences of fatigue and functional limitation due to fatigue seem to be related mainly to psychological but also to physiological influencing factors, with depressive symptoms, insomnia problems and dyspnoea as the most prominent factors. Systemic inflammation was not associated with perception of fatigue but surfactant protein D was connected to some dimensions of the impact of fatigue.

Decrease of DHEA-S concentration succeeding a micro-dose thumb exertion: mood-state determinants reflect stress-biomarker responses

Background

The present study examined the effect of a micro-dose of resistance-exercise on serum DHEA-S, IL-6 and mood-state determinants. Potential relationships between mood and the biomarkers were also studied with the aim of directing research on non-invasive exercise-monitoring methods.

Methods

30 male participants (20 weightlifting-trained; 10 untrained) were separated into 3 groups of 10: weightlifting experimental (WL_EXP); untrained experimental (UT_EXP); weightlifting placebo (WL_PLA). WL_EXP and UT_EXP performed four 60-s isometric thumb exertions separated by 60-s rest intervals in a single-blinded placebo-controlled study. Participants were assessed over a 60-min post-intervention recovery period for changes in serum DHEA-S and IL-6, and mood-state determinants (vigour, tension, fatigue).

Results

DHEA-S changed in UT_EXP only; a decrease from 20- to 60-min post-exercise (Δ36.9 %, p < 0.01). DHEA-S remained below baseline at the final time-point (Δ35.3 %, p = 0.012). Tension decreased immediately post-exercise in WL_EXP (Δ86.7 %, p = 0.022), whereas UT_EXP showed a delayed decrease which continued up to 60-min post-intervention (Δ100 %, p < 0.01). Relative to fatigue scores recorded immediately post-exercise, WL_EXP decreased within the first 10-min post-intervention (Δ22.2 %, p < 0.01) whereas UT_EXP showed a delayed decrease evident at 20-min post-intervention (Δ25 %, p < 0.01). Serum IL-6 and vigour scores remained unchanged across groups (p > 0.05) and WL_PLA did not change for any measured variable (p > 0.05).

Conclusions

The authors conclude that a micro-dose of resistance-exercise can reduce serological DHEA-S concentration within 60-min of exercise cessation. Additionally, mood-state assessment in untrained individuals can be considered for non-invasively indicating exercise-induced concentration changes in the stress biomarker, DHEA-S, providing prospects for the development of safer, more sophisticated exercise-monitoring practice.

Blood-Brain Barrier Disruption Induced by Chronic Sleep Loss: Low-Grade Inflammation May Be the Link

Sleep is a vital phenomenon related to immunomodulation at the central and peripheral level. Sleep deficient in duration and/or quality is a common problem in the modern society and is considered a risk factor to develop neurodegenerative diseases. Sleep loss in rodents induces blood-brain barrier disruption and the underlying mechanism is still unknown. Several reports indicate that sleep loss induces a systemic low-grade inflammation characterized by the release of several molecules, such as cytokines, chemokines, and acute-phase proteins; all of them may promote changes in cellular components of the blood-brain barrier, particularly on brain endothelial cells. In the present review we discuss the role of inflammatory mediators that increase during sleep loss and their association with general disturbances in peripheral endothelium and epithelium and how those inflammatory mediators may alter the blood-brain barrier. Finally, this manuscript proposes a hypothetical mechanism by which sleep loss may induce blood-brain barrier disruption, emphasizing the regulatory effect of inflammatory molecules on tight junction proteins.

Positive Affect and Inflammatory Activity in Breast Cancer Survivors: Examining the Role of Affective Arousal

OBJECTIVE

Given the importance of positive affect and inflammation for well-being in cancer survivors, the current study examined the relationship between high- and low-arousal positive affect and inflammation in 186 women who completed treatment of early-stage breast cancer.

METHODS

Measures of high- and low-arousal positive affect were completed within 3 months after treatment completion (baseline). Plasma markers of inflammation, including soluble tumor necrosis factor receptor type II (sTNF-RII), C-reactive protein (CRP), and interleukin-1 receptor antagonist, were assessed at baseline and 6- and 12-month follow-up assessments.

RESULTS

Multilevel modeling analyses showed that high-arousal positive affect was associated with lower levels of sTNF-RII, a marker of TNF activity, at treatment completion and prospectively predicted maintenance of these differences through the 6- and 12-month follow-ups adjusting for biobehavioral confounds (b = -0.055, t(156) = -2.40, p = .018). However, this association was no longer significant when adjusting for fatigue. Exploratory analyses showed that low-arousal positive affect was associated with lower levels of CRP at treatment completion and through the 6- and 12-month follow-ups; this association remained significant after adjusting for fatigue and other confounds (b = -0.217, t(152) = -2.04, p = .043).

CONCLUSIONS

The relationship of high-arousal positive affect (e.g., "active") with sTNF-RII seems to be driven by the overlap of high-arousal positive affect with fatigue, whereas the relationship of low-arousal positive affect (e.g., "calm") with CRP was independent of fatigue. Future research should consider affective arousal when examining the association of positive affect with inflammation as this facet of positive affect may have important implications for interpretation of results.

Suppression of Locomotor Activity in Female C57Bl/6J Mice Treated with Interleukin-1β: Investigating a Method for the Study of Fatigue in Laboratory Animals

Fatigue is a disabling symptom in patients with multiple sclerosis and Parkinson’s Disease, and is also common in patients with traumatic brain injury, cancer, and inflammatory disorders. Little is known about the neurobiology of fatigue, in part due to the lack of an approach to induce fatigue in laboratory animals. Fatigue is a common response to systemic challenge by pathogens, a response in part mediated through action of the pro-inflammatory cytokine interleukin-1 beta (IL-1β). We investigated the behavioral responses of mice to IL-1β. Female C57Bl/6J mice of 3 ages were administered IL-1β at various doses i.p. Interleukin-1β reduced locomotor activity, and sensitivity increased with age. Further experiments were conducted with middle-aged females. Centrally administered IL-1β dose-dependently reduced locomotor activity. Using doses of IL-1β that caused suppression of locomotor activity, we measured minimal signs of sickness, such as hyperthermia, pain or anhedonia (as measured with abdominal temperature probes, pre-treatment with the analgesic buprenorphine and through sucrose preference, respectively), all of which are responses commonly reported with higher doses. We found that middle-aged orexin^-/- mice showed equivalent effects of IL-1β on locomotor activity as seen in wild-type controls, suggesting that orexins are not necessary for IL-1β -induced reductions in wheel-running. Given that the availability and success of therapeutic treatments for fatigue is currently limited, we examined the effectiveness of two potential clinical treatments, modafinil and methylphenidate. We found that these treatments were variably successful in restoring locomotor activity after IL-1β administration. This provides one step toward development of a satisfactory animal model of the multidimensional experience of fatigue, a model that could allow us to determine possible pathways through which inflammation induces fatigue, and could lead to novel treatments for reversal of fatigue.

Chrono-immunology: progress and challenges in understanding links between the circadian and immune systems

Development of inflammatory diseases, such as metabolic syndrome and cancer, is prevalent in individuals that encounter continuous disruption of their internal clock. Further, daily oscillations in susceptibility to infection as well as a multitude of other immunological processes have been described. Much progress has been made and various mechanisms have been proposed to explain circadian variations in immunity; yet much is still unknown. Understanding the crosstalk between the circadian and the immune systems will allow us to manipulate clock outputs to prevent and treat inflammatory diseases in individuals at risk. This review briefly summarizes current knowledge about circadian rhythms and their role in the immune system and highlights progress and challenges in chrono-immunological research.

Fatigue in rheumatic diseases

Fatigue is a common and important problem in many diseases including rheumatologic illnesses, and it has a negative impact on health-related quality of life. Fatigue is described as having an impact on multiple aspects of a patient's life. There is a need for knowledge about causes of and treatments for fatigue to ensure that patient outcomes are improved. There are several effective treatment strategies available for fatigue including pharmacological and non-pharmacological therapies. We aim to provide an overview of fatigue in rheumatologic disorders and some recommendations on its optimal management.

Rapid eye movement-sleep is reduced in patients with acute uncomplicated diverticulitis-an observational study

Introduction. Sleep disturbances are commonly found in patients in the postoperative period. Sleep disturbances may give rise to several complications including cardiopulmonary instability, transient cognitive dysfunction and prolonged convalescence. Many factors including host inflammatory responses are believed to cause postoperative sleep disturbances, as inflammatory responses can alter sleep architecture through cytokine-brain interactions. Our aim was to investigate alteration of sleep architecture during acute infection and its relationships to inflammation and clinical symptoms. Materials & Methods. In this observational study, we included patients with acute uncomplicated diverticulitis as a model to investigate the isolated effects of inflammatory responses on sleep. Eleven patients completed the study. Patients were admitted and treated with antibiotics for two nights, during which study endpoints were measured by polysomnography recordings, self-reported discomfort scores and blood samples of cytokines. One month later, the patients, who now were in complete remission, were readmitted and the endpoints were re-measured (the baseline values). Results. Total sleep time was reduced 4% and 7% the first (p = 0.006) and second (p = 0.014) nights of diverticulitis, compared to baseline, respectively. The rapid eye movement sleep was reduced 33% the first night (p = 0.016), compared to baseline. Moreover, plasma IL-6 levels were correlated to non-rapid eye movement sleep, rapid eye movement sleep and fatigue. Conclusion. Total sleep time and rapid eye movement sleep were reduced during nights with active diverticulitis and correlated with markers of inflammation.

Proinflammatory cytokines correlate with depression and anxiety in colorectal cancer patients

The objective of this study was to investigate whether serum cytokine levels correlate with depression and anxiety in colorectal cancer (CRC) patients. Twenty patients hospitalized for surgical resection of CRC were included in the study group and twenty healthy volunteers comprised the control group. Depression and anxiety were analyzed using the Hospital Anxiety and Depression Scale (HADS), and serum levels of IL-1β, IL-6, IL-8, IL-10, IL-12, TNF-α, and TGF-β were measured by Cytometric Bead Array. We found that more than half of CRC patients presented clinically significant levels of anxiety or depression, and 65% of them manifested a combination of severe anxiety and depression. CRC patients had increased serum levels of IL-1β, IL-6, IL-8, and TNF-α but lower IL-10 concentrations. Correlation analysis between HADS score and cytokine levels revealed a positive association of anxiety and/or depression with IL-1β, IL-6, IL-8, and TNF-α and a negative correlation with IL-10. These results indicate that circulating proinflammatory cytokines are involved in the pathophysiology of anxiety and depression in CRC patients. A better understanding of the molecular mechanisms involved in these psychological disorders will allow the design of therapeutic interventions that lead to an improved quality of life and overall survival of CRC patients.

Cancer-related fatigue--mechanisms, risk factors, and treatments

Fatigue is one of the most common adverse effects of cancer that might persist for years after treatment completion in otherwise healthy survivors. Cancer-related fatigue causes disruption in all aspects of quality of life and might be a risk factor of reduced survival. The prevalence and course of fatigue in patients with cancer have been well characterized and there is growing understanding of the underlying biological mechanisms. Inflammation seems to have a key role in fatigue before, during, and after cancer-treatment. However, there is a considerable variability in the presentation of cancer-related fatigue, much of which is not explained by disease-related or treatment-related characteristics, suggesting that host factors might be important in the development and persistence of this symptom. Indeed, longitudinal studies have identified genetic, biological, psychosocial, and behavioural risk factors associated with cancer-related fatigue. Although no current gold-standard treatment for fatigue is available, a variety of intervention approaches have shown beneficial effects in randomized controlled trials, including physical activity, psychosocial, mind-body, and pharmacological treatments. This Review describes the mechanisms, risk factors, and possible interventions for cancer-related fatigue, focusing on recent longitudinal studies and randomized trials that have targeted fatigued patients.

Why sleep is important for health: a psychoneuroimmunology perspective

Sleep has a critical role in promoting health. Research over the past decade has documented that sleep disturbance has a powerful influence on the risk of infectious disease, the occurrence and progression of several major medical illnesses including cardiovascular disease and cancer, and the incidence of depression. Increasingly, the field has focused on identifying the biological mechanisms underlying these effects. This review highlights the impact of sleep on adaptive and innate immunity, with consideration of the dynamics of sleep disturbance, sleep restriction, and insomnia on (a) antiviral immune responses with consequences for vaccine responses and infectious disease risk and (b) proinflammatory immune responses with implications for cardiovascular disease, cancer, and depression. This review also discusses the neuroendocrine and autonomic neural underpinnings linking sleep disturbance and immunity and the reciprocal links between sleep and inflammatory biology. Finally, interventions are discussed as effective strategies to improve sleep, and potential opportunities are identified to promote sleep health for therapeutic control of chronic infectious, inflammatory, and neuropsychiatric diseases.