Liver-brain inflammation axis

Fatigued Patients with Chronic Liver Disease Have Subtle Aberrations of Sleep, Melatonin and Cortisol Circadian Rhythms

AIMS

We sought to examine whether disturbances in central and peripheral circadian rhythms were related to the experience of fatigue in patients with chronic liver disease (CLD).

METHODS

Fatigued and non-fatigued patients with compensated CLD were enrolled in a prospective pilot study. Patients underwent a one week evaluation of free-living sleep and physical activity patterns, followed by a 24-hour admission, during which they underwent serial blood sampling, polysomnography, a 6-minute walk test and continuous core temperature measurements under standardized conditions. Blood samples were analyzed for liver tests, melatonin levels, lipids, and cortisol. Circadian rhythms were analyzed using single cosinor analyses.

RESULTS

Six fatigued and six non-fatigued patients were studied; five participants had cirrhosis. Fatigue severity was positively associated higher peak melatonin levels (rho=0.59, p=0.04) and a delay in night-time melatonin peak and inversely associated with sleep efficiency (rho=-0.63, p=0.04). Polysomnography, 6-minute walk test, and core temperature measurements did not differ significantly between the fatigued and non-fatigued patients. Although liver enzymes, bilirubin and albumin demonstrated a circadian pattern, it was not associated with fatigue. Fatigued patients showed a blunted and delayed cortisol rhythm and fatigue was strongly correlated with cortisol amplitude (rho=-0.77, p=0.004) and phase (r=-0.66, p=0.02).

CONCLUSION

Subtle aberrations in melatonin and adrenal circadian rhythms, as well as reduced sleep efficiency, likely contribute to fatigue in patients with CLD. These abnormalities may ultimately be a therapeutic target to improve quality of life for fatigued patients with CLD.

Voluntary exposure to a toxin: the genetic influence on ethanol consumption

Ethyl alcohol is a toxin that, when consumed at high levels, produces organ damage and death. One way to prevent or ameliorate this damage in humans is to reduce the exposure of organs to alcohol by reducing alcohol ingestion. Both the propensity to consume large volumes of alcohol and the susceptibility of human organs to alcohol-induced damage exhibit a strong genetic influence. We have developed an integrative genetic/genomic approach to identify transcriptional networks that predispose complex traits, including propensity for alcohol consumption and propensity for alcohol-induced organ damage. In our approach, the phenotype is assessed in a panel of recombinant inbred (RI) rat strains, and quantitative trait locus (QTL) analysis is performed. Transcriptome data from tissues/organs of naïve RI rat strains are used to identify transcriptional networks using Weighted Gene Coexpression Network Analysis (WGCNA). Correlation of the first principal component of transcriptional coexpression modules with the phenotype across the rat strains, and overlap of QTLs for the phenotype and the QTLs for the coexpression modules (module eigengene QTL) provide the criteria for identification of the functionally related groups of genes that contribute to the phenotype (candidate modules). While we previously identified a brain transcriptional module whose QTL overlapped with a QTL for levels of alcohol consumption in HXB/BXH RI rat strains and 12 selected rat lines, this module did not account for all of the genetic variation in alcohol consumption. Our search for QTL overlap and correlation of coexpression modules with phenotype can, however, be applied to any organ in which the transcriptome has been measured, and this represents a holistic approach in the search for genetic contributors to complex traits. Previous work has implicated liver/brain interactions, particularly involving inflammatory/immune processes, as influencing alcohol consumption levels. We have now analyzed the liver transcriptome of the HXB/BXH RI rat panel in relation to the behavioral trait of alcohol consumption. We used RNA-Seq and microarray data to construct liver transcriptional networks, and identified a liver candidate transcriptional coexpression module that explained 24% of the genetic variance in voluntary alcohol consumption. The transcripts in this module focus attention on liver secretory products that influence inflammatory and immune signaling pathways. We propose that these liver secretory products can interact with brain mechanisms that affect alcohol consumption, and targeting these pathways provides a potential approach to reducing high levels of alcohol intake and also protecting the integrity of the liver and other organs.

Banxia-houpu decoction restores glucose intolerance in CUMS rats through improvement of insulin signaling and suppression of NLRP3 inflammasome activation in liver and brain

ETHNOPHARMACOLOGICAL RELEVANCE

Banxia-houpu decoction is a famous formula in traditional Chinese medicine (TCM) with the powerful anti-depressant activity.

AIM OF THE STUDY

This study aimed to investigate the effect of Banxia-houpu decoction on glucose intolerance associated with anhedonia in chronic unpredictable mild stress (CUMS) rats, then to explore its underlying pharmacological mechanisms.

MATERIALS AND METHODS

After 6-week CUMS procedure, male Wistar rats were given Banxia-houpu decoction (3.29 and 6.58g/kg, intragastrically) for 6 weeks. Sucrose solution consumption test was employed to evaluate the anhedonia behavior. Oral glucose tolerance test (OGTT) was used to determine glucose tolerance. Serum levels of corticosterone, corticotropin-releasing factor (CRF), insulin and interleukin-1 beta (IL-1β) were measured by commercial enzyme-linked immunosorbent assay kits, respectively. Furthermore, the key proteins for insulin signaling, as well as nod-like receptor family pyrin domain containing 3 (NLRP3) inflammasome, were analyzed by Western blot in periphery liver and brain regions hypothalamus, hippocampus and prefrontal cortex, respectively.

RESULTS

Banxia-houpu decoction significantly increased sucrose solution consumption and decreased serum corticosterone and CRF levels in CUMS rats, further demonstrating its antidepressant activity. More importantly, Banxia-houpu decoction improved glucose tolerance in OGTT in this animal model. Furthermore, it protected against CUMS-induced insulin signaling impairment in the liver, as well as hypothalamus and prefrontal cortex in rats. Although without significant effect on serum IL-1β levels, Banxia-houpu decoction inhibited NLRP3 inflammasome activation in the liver, hypothalamus, hippocampus and prefrontal cortex of CUMS rats, respectively.

CONCLUSIONS

The present study demonstrates that Banxia-houpu decoction suppresses NLRP3 inflammasome activation and improves insulin signaling impairment in both periphery liver and brain regions in CUMS rats, possibly contributing to its anti-depressive effect with glucose tolerance improvement. These results may provide the evidence that Banxia-houpu decoction is a potential antidepressant with the advantage to reduce the risk of comorbid depression with type 2 diabetes mellitus.

Unveiling Cerebral Leishmaniasis: parasites and brain inflammation in Leishmania donovani infected mice

Visceral leishmaniasis (VL) is a systemic disease with multifaceted clinical manifestations, including neurological signs, however, the involvement of the nervous system during VL is underestimated. Accordingly, we investigated both brain infection and inflammation in a mouse model of VL. Using bioluminescent Leishmania donovani and real-time 2D-3D imaging tools, we strikingly detected live parasites in the brain, where we observed a compartmentalized dual-phased inflammation pattern: an early phase during the first two weeks post-infection, with the prompt arrival of neutrophils and Ly6Chigh macrophages in an environment presenting a variety of pro-inflammatory mediators (IFN-γ, IL-1β, CXCL-10/CXCR-3, CCL-7/CCR-2), but with an intense anti-inflammatory response, led by IL-10; and a re-inflammation phase three months later, extremely pro-inflammatory, with novel upregulation of mediators, including IL-1β, TNF-α and MMP-9. These new data give support and corroborate previous studies connecting human and canine VL with neuroinflammation and blood-brain barrier disruption, and conclusively place the brain among the organs affected by this parasite. Altogether, our results provide convincing evidences that Leishmania donovani indeed infects and inflames the brain.

Anatomical changes correlated with chronic pain in forensic medicine

This study was performed to determine the relationships between chronic pain and anatomic changes that may occur in the body. Autopsies were performed on fatalities that required death investigation in Linn County, IA, or adjacent and nearby areas. Persons with chronic pain were older than the control population at the time of death. Diabetes, hypertension and depression were more common in persons with chronic pain. Certain causes of death may also have been related to chronic pain. The heart, lungs, liver, spleen and kidneys were significantly heavier in persons with chronic pain; emphysema and pleural and abdominal adhesions were more common in persons with chronic pain. There appear to have been diffuse changes in the body related to chronic pain. These changes may have been mediated by a number of systemic mechanisms that are involved with chronic pain, including cardiovascular activity, the immune system, the neuroendocrine system and others.

Protective Role of the Hepatic Vagus Nerve against Liver Metastasis in Mice

OBJECTIVE(S)

Although accumulating evidence has shown that the autonomic nervous system is involved in liver pathology, its role in regulating cancer development remains unclear. The purpose of this study was to elucidate its detailed mechanisms.

METHODS

A mouse model of liver metastasis of colorectal cancer was used. To elucidate the potential mechanisms involved, we examined the effect of selective hepatic vagotomy on the survival rate and liver-to-body weight. We further evaluated the possible involvement of the hepatic sympathetic nerve fibers in this model.

RESULTS

The mortality rate and the liver-to-body weight ratio after cancer inoculation were significantly higher in the vagotomized mice than in the sham-operated mice. The vagotomized mice exhibited a transient decrease in hepatic norepinephrine levels following cancer inoculation. Interestingly, the vagotomy-induced exacerbation of liver metastasis was attenuated by supplementary norepinephrine or phenylephrine, a selective α1-adrenoceptor agonist, but not by clonidine, a selective α2-adrenoceptor agonist.

CONCLUSION

Collectively, these results suggest that the hepatic vagus nerve may play a protective role against liver metastasis. Hepatic sympathetic nerves may also be involved as a protective efferent loop, possibly acting through the α1-adrenoceptor.

Non-alcoholic fatty liver disease induces signs of Alzheimer's disease (AD) in wild-type mice and accelerates pathological signs of AD in an AD model

Background

Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease afflicting about one third of the world’s population and 30 % of the US population. It is induced by consumption of high-lipid diets and is characterized by liver inflammation and subsequent liver pathology. Obesity and consumption of a high-fat diet are known to increase the risk of Alzheimer’s disease (AD). Here, we investigated NAFLD-induced liver inflammation in the pathogenesis of AD.

Methods

WT and APP-Tg mice were fed with a standard diet (SD) or a high-fat diet (HFD) for 2, 5 months, or 1 year to induce NAFLD. Another set of APP-Tg mice were removed from HFD after 2 months and put back on SD for 3 months.

Results

During acute phase NAFLD, WT and APP-Tg mice developed significant liver inflammation and pathology that coincided with increased numbers of activated microglial cells in the brain, increased inflammatory cytokine profile, and increased expression of toll-like receptors. Chronic NAFLD induced advanced pathological signs of AD in both WT and APP-Tg mice, and also induced neuronal apoptosis. We observed decreased brain expression of low-density lipoprotein receptor-related protein-1 (LRP-1) which is involved in β-amyloid clearance, in both WT and APP-Tg mice after ongoing administration of the HFD. LRP-1 expression correlated with advanced signs of AD over the course of chronic NAFLD. Removal of mice from HFD during acute NAFLD reversed liver pathology, decreased signs of activated microglial cells and neuro-inflammation, and decreased β-amyloid plaque load.

Conclusions

Our findings indicate that chronic inflammation induced outside the brain is sufficient to induce neurodegeneration in the absence of genetic predisposition.

Electronic supplementary material

The online version of this article (doi:10.1186/s12974-015-0467-5) contains supplementary material, which is available to authorized users.

Effect of Regular Exercise on Inflammation Induced by Drug-resistant Staphylococcus aureus 3089 in ICR mice

Obesity is often associated with irregular dietary habits and reduced physical activity. Regular exercise induces a metabolic response that includes increased expression of various cytokines, signaling proteins and hormones, and reduced adipocyte size. In this study, mice performed a swimming exercise for 10 min/day, 5 days/week for 3 weeks. We then investigated the effect of this exercise regimen on inflammation induced by infection with drug-resistant Staphylococcus aureus strain 3089 (DRSA). In humans, DRSA causes dermatitis and pneumonitis. Similarly, DRSA induced inflammatory pneumonitis in both no-exercise (No-EX) and swim-trained (SW-EX) ICR mice. Regular exercise increased levels of the pro-inflammatory cytokines TNF-α and IL-1β and nitric oxide in both serum and whole lung tissue in SW-EX, as compared to No-EX control mice. Moreover, levels of the antimicrobial peptide cathelicidin were significantly increased in visceral adipose tissue and whole lung tissue in the SW-EX group, and this was accompanied by a reduction in the size of visceral adipocytes. In addition, levels of the inflammation marker peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1) were not increased in the lung tissue of SW-EX mice. These findings suggest that in these model mice, regular exercise strengthens immune system responses, potentially preventing or mitigating infectious disease.

Has bioscience reconciled mind and body?

AIMS AND OBJECTIVES

The aim of this discursive paper is to explore the question 'has biological science reconciled mind and body?'.

BACKGROUND

This paper has been inspired by the recognition that bioscience has a historical reputation for privileging the body over the mind. The disregard for the mind (emotions and behaviour) cast bioscience within a 'mind-body problem' paradigm. It has also led to inherent limitations in its capacity to contribute to understanding the complex nature of health.

DESIGN

This is a discursive paper.

METHODS

Literature from the history and sociology of science and psychoneuroimmunology (1975-2015) inform the arguments in this paper. The historical and sociological literature provides the basis for a socio-cultural debate on mind-body considerations in science since the 1970s. The psychoneuroimmunology literature draws on mind-body bioscientific theory as a way to demonstrate how science is reconciling mind and body and advancing its understanding of the interconnections between emotions, behaviour and health.

RESULTS

Using sociological and biological evidence, this paper demonstrates how bioscience is embracing and advancing its understanding of mind-body interconnectedness. It does this by demonstrating the emotional and behavioural alterations that are caused by two common phenomena; prolonged, chronic peripheral inflammation and prolonged psychological stress. The evidence and arguments provided has global currency that advances understanding of the inter-relationship between emotions, behaviour and health.

CONCLUSIONS

This paper shows how bioscience has reconciled mind and body. In doing so, it has advanced an understanding of science's contribution to the inter-relationship between emotions, behaviour and health.

RELEVANCE TO CLINICAL PRACTICE

The biological evidence supporting mind-body science has relevance to clinical practice for nurses and other healthcare professions. This paper discusses how this evidence can inform and enhance clinical practice directly and through research, education and policy.

Microglia-dependent alteration of glutamatergic synaptic transmission and plasticity in the hippocampus during peripheral inflammation

Peripheral inflammatory diseases are often associated with behavioral comorbidities including anxiety, depression, and cognitive dysfunction, but the mechanism for these is not well understood. Changes in the neuronal and synaptic functions associated with neuroinflammation may underlie these behavioral abnormalities. We have used a model of colonic inflammation induced by 2,4,6-trinitrobenzenesulfonic acid in Sprague Dawley rats to identify inflammation-induced changes in hippocampal synaptic transmission. Hippocampal slices obtained 4 d after the induction of inflammation revealed enhanced Schaffer collateral-induced excitatory field potentials in CA1 stratum radiatum. This was associated with larger-amplitude mEPSCs, but unchanged mEPSC frequencies and paired-pulse ratios, suggesting altered postsynaptic effects. Both AMPA- and NMDA-mediated synaptic currents were enhanced, and analysis of AMPA-mediated currents revealed increased contributions of GluR2-lacking receptors. In keeping with this, both transcripts and protein levels of the GluR2 subunit were reduced in hippocampus. Both long-term potentiation (LTP) and depression (LTD) were significantly reduced in hippocampal slices taken from inflamed animals. Chronic administration of the microglial/macrophage activation inhibitor minocycline to the inflamed animals both lowered the level of the cytokine tumor necrosis factor α in the hippocampus and completely abolished the effect of peripheral inflammation on the field potentials and synaptic plasticity (LTP and LTD). Our results reveal profound synaptic changes caused by a mirror microglia-mediated inflammatory response in hippocampus during peripheral organ inflammation. These synaptic changes may underlie the behavioral comorbidities seen in patients.

A review of the neuro- and systemic inflammatory responses in post concussion symptoms: Introduction of the "post-inflammatory brain syndrome" PIBS

Post-concussion syndrome is an aggregate of symptoms that commonly present together after head injury. These symptoms, depending on definition, include headaches, dizziness, neuropsychiatric symptoms, and cognitive impairment. However, these symptoms are common, occurring frequently in non-head injured controls, leading some to question the existence of post-concussion syndrome as a unique syndrome. Therefore, some have attempted to explain post-concussion symptoms as post-traumatic stress disorder, as they share many similar symptoms and post-traumatic stress disorder does not require head injury. This explanation falls short as patients with post-concussion syndrome do not necessarily experience many key symptoms of post-traumatic stress disorder. Therefore, other explanations must be sought to explain the prevalence of post-concussion like symptoms in non-head injury patients. Many of the situations in which post-concussion syndrome like symptoms may be experienced such as infection and post-surgery are associated with systemic inflammatory responses, and even neuroinflammation. Post-concussion syndrome itself has a significant neuroinflammatory component. In this review we examine the evidence of neuroinflammation in post-concussion syndrome and the potential role systemic inflammation plays in post-concussion syndrome like symptoms. We conclude that given the overlap between these conditions and the role of inflammation in their etiologies, a new term, post-inflammatory brain syndromes (PIBS), is necessary to describe the common outcomes of many different inflammatory insults. The concept of post-concussion syndrome is in its evolution therefore, the new term post-inflammatory brain syndromes provides a better understanding of etiology of its wide-array of symptoms and the wide array of conditions they can be seen in.

Systemic inflammation is associated with increased intrahepatic resistance and mortality in alcohol-related acute-on-chronic liver failure

BACKGROUND & AIMS

Acute-on-chronic liver failure (ACLF) is characterized by acute deterioration of cirrhosis, systemic inflammation and multi-organ failure. Inflammation is also key to the pathobiology of portal hypertension. This study aims to define the relationship between systemic and hepatic haemodynamics in patients with ACLF.

METHODS

Sixty patients with alcoholic cirrhosis were prospectively enrolled - stable cirrhosis (SC, n = 27), acute decompensation without ACLF (AD, n = 14) and ACLF (n = 19) - and managed with standard therapy. Systemic and hepatic haemodynamic studies were performed, and patients were followed up for 3 months. Plasma norepinephrine, cytokine profile, nitrate/nitrite and malondialdehyde levels were measured.

RESULTS

Three-month mortality was as follows: SC - none; AD - 14%; ACLF - 47.2% (P < 0.001). Mean arterial pressure was lowest in the ACLF group (P < 0.001). ACLF patients had significantly higher hepatic vein pressure gradient (HVPG), while the hepatic blood flow was markedly reduced with an increase in intrahepatic resistance, which predicted mortality (AUROC: 0.87, P < 0.0001). In ACLF, the severity of intrahepatic resistance correlated with markers of inflammatory response, norepinephrine levels, creatinine levels and severity of encephalopathy. Modelling data showed that the high norepinephrine levels in ACLF may contribute to the right shift of the HVPG-hepatic blood flow relationship and its levels correlated with inflammatory markers and mortality (AUROC: 0.90; P < 0.0001).

CONCLUSIONS

The disturbances in systemic and hepatic haemodynamics in alcohol-related ACLF are associated with dysregulated inflammation, multi-organ failure and marked activation of the sympathetic nervous system. These abnormalities predict high mortality rates in alcohol-related ACLF patients.

Shared symptoms and putative biological mechanisms in chronic liver disease: implications for biobehavioral research

Liver disease affects over 25 million people in the United States and, despite advances in medical management resulting in increased survival, a majority of these individuals report multiple co-occurring symptoms that severely impair functioning and quality of life. The purpose of this review is to (1) propose defining these co-occurring symptoms as a symptom cluster of chronic liver disease (CLD), (2) discuss putative underlying biological mechanisms related to CLD, including the liver-gut-brain axis and influence of the microbiome, and (3) discuss the implications for biobehavioral research in this patient population. Biobehavioral research focusing on the interrelated, and possibly synergistic, mechanisms of these symptoms may lead to the development and testing of targeted symptom management interventions for improving function and quality of life in this growing patient population.

Risk of developing depressive disorders following rheumatoid arthritis: a nationwide population-based study

Background & Aims

To evaluate the risk of depressive disorders among rheumatoid arthritis (RA) by using the Taiwan National Health Insurance Research Database (NHIRD).

Methods

We conducted a retrospective study of a matched cohort of 18 285 participants (3 657 RA patients and 14 628 control patients) who were selected from the NHIRD. Patients were observed for a maximum of 10 years to determine the rates of newly diagnosed depressive disorders, and Cox regression was used to identify the risk factors associated with depressive disorders in RA patients.

Results

During the 10-year follow-up period, 205 (11.2 per 1000 person-years) RA patients and 384 (5.1 per 1000 person-years) control patients were diagnosed with depressive disorders. In RA patients, most depressive disorders (n = 163, 80%) developed with five years of being diagnosed with RA. The incidence risk ratio of depressive disorders between RA patients and control patients was 2.20 (95% confidence interval [CI], 1.84–2.61, P<.001). After adjusting for age, sex, and comorbidities, RA patients were 2.06 times more likely to develop depressive disorders (95% CI, 1.73–2.44, P<.001) compared with the control patients. Hyperthyroidism (HR = 1.67) was an independent risk factor for depressive disorders in patients with RA.

Conclusions

The likelihood of developing depressive disorders is greater among RA patients than among patients without RA. Symptoms of depression should be sought in patients with RA.

Anxiety and depressive disorders among patients with esophageal cancer in Taiwan: a nationwide population-based study

BACKGROUND

The comorbidity of depression with anxiety disorders is associated with poorer treatment outcomes, worse quality of life, poorer adherence to treatment, and greater suicide risk in cancer patients.

OBJECTIVE

To assess the risk of comorbid anxiety and depressive disorders after the diagnosis of esophageal cancer compared with a matched cohort by using the Taiwan National Health Insurance Research Database (NHIRD).

METHODS

We conducted a retrospective study of 28,454 patients (14,227 patients with esophageal cancer and 14,227 matched patients) who were selected from the NHIRD. Patients were observed for a maximum of 12 years to determine the incidence of new-onset anxiety and depressive disorders for which antidepressants had been prescribed. A Cox regression analysis was performed to identify the risk factors associated with anxiety and depressive disorders in esophageal cancer patients.

RESULTS

The cumulative incidence of anxiety and depressive disorders in the esophageal cancer patients was significantly higher than that in the matched cohort (P < .001). The adjusted hazard ratio (HR) was 2.24 (95 % confidence interval, CI = 1.95-2.56, P < .001) in the esophageal cancer cohort compared with the matched cohort. Independent risk factors for developing anxiety and depressive disorders among the patients with esophageal cancer included cirrhosis, cerebrovascular disease, and surgical treatment.

CONCLUSION

Esophageal cancer may be a prominent risk factor for anxiety and depressive disorders. Based on our data, we suggest that attention should be focused on esophageal cancer patients with comorbid cirrhosis and cerebrovascular disease and those who have received surgical interventions.

Fasting Induces IL-1 Resistance and Free-Fatty Acid-Mediated Up-Regulation of IL-1R2 and IL-1RA

OBJECTIVE

Weight-loss is a near societal obsession and many diet programs use significant calorie restriction including fasting/short term starvation to generate rapid effects. Fasting is also a well-recognized cause of immunosuppression especially within the innate immune system. In this study, we sought to determine if the IL-1 arm of the neuroimmune system was down-regulated by a 24 h fast and how fasting might generate this effect.

DESIGN

Mice were allowed ad libitum access to food or had food withheld for 24 h. Expression of the endogenous IL-1 antagonists, IL-1 receptor type 2 (IL-1R2), and IL-1 receptor antagonist (IL-1RA) was determined as were sickness behaviors before and after IL-1β administration.

RESULTS

Fasting markedly increased gene expression of IL-1R2 (83-fold in adipose tissue, 9.5-fold in liver) and IL-1RA (68-fold in liver). Fasted mice were protected from IL-1β-induced weight-loss, hypoglycemia, loss of locomotor, and social anxiety. These protections were coupled to a large positive interaction of fasting and IL-1β on IL-1R2 gene expression in adipose tissue and liver (2.6- and 1.6-fold, respectively). Fasting not only increased IL-1RA and IL-1R2 protein 2.5- and 3.2-fold, respectively, in liver but also increased IL-1R2 1.8-fold in adipose tissue. Fasting, in turn, triggered a 2.4-fold increase in plasma free-fatty acids (FFAs) and a 2.1-fold increase in plasma corticosterone. Inhibition, of glucocorticoid action with mifepristone did not impact fasting-dependent IL-1R2 or IL-1RA gene expression. Administration of the FFA, palmitate, to mice increased liver IL-1R2 and IL-1RA gene expression by 14- and 11-fold, respectively.

CONCLUSION

These findings indicate that fasting augments expression of endogenous IL-1 antagonists inducing IL-1 resistance. Fasting-induced increases in plasma FFAs appears to be a signal that drives immunosuppression during fasting/short term starvation.

Risk of depressive disorder following non-alcoholic cirrhosis: a nationwide population-based study

BACKGROUND & AIMS

To evaluate the risk of depressive disorders among non-alcoholic patients by using the Taiwan National Health Insurance Research Database (NHIRD).

METHODS

We conducted a retrospective study of a matched cohort of 52 725 participants (10 545 non-alcoholic cirrhotic patients and 42 180 control patients) who were selected from the NHIRD. Patients were observed for a maximum of 11 years to determine the rates of newly onset depressive disorders, and Cox regression was used to identify the risk factors associated with depressive disorders in cirrhotic patients.

RESULTS

During the 11-year follow-up period, 395 (3.75%) non-alcoholic cirrhotic patients and 1 183 (2.80%) control patients were diagnosed with depressive disorders. The incidence risk ratio of depressive disorders between non-alcoholic cirrhotic patients and control patients was 1.76 (95% CI, 1.57-1.98, P<.001). After adjusting for age, sex, and comorbidities, non-alcoholic cirrhotic patients were 1.75 times more likely to develop depressive disorders (95% CI, 1.56-1.96, P<.001) compared with the control patients. The hazard ratios for patients younger than 60 years old (1.31) and female (1.25) indicated that each is an independent risk factor for depressive disorders in non-alcoholic cirrhotic patients.

CONCLUSIONS

The likelihood of developing depressive disorders is greater among non-alcoholic cirrhotic patients than among patients without cirrhosis. Symptoms of depression should be sought in patients with cirrhosis.

Liver-brain interactions in inflammatory liver diseases: implications for fatigue and mood disorders

Chronic inflammatory liver diseases are often accompanied by behavior alterations including fatigue, mood disorders, cognitive dysfunction and sleep disturbances. These altered behaviors can adversely affect patient quality of life. The communication pathways between the inflamed liver and the brain that mediate changes in central neural activity leading to behavior alterations during liver inflammation are poorly understood. Neural and humoral communication pathways have been most commonly implicated as driving peripheral inflammation to brain signaling. Classically, the cytokines TNFα, IL-1β and IL-6 have received the greatest scientific attention as potential mediators of this communication pathway. In mice with liver inflammation we have identified a novel immune-mediated liver-to-brain communication pathway whereby CCR2(+) monocytes found within the peripheral circulation transmigrate into the brain parenchyma in response to MCP-1/CCL2 expressing activated microglia. Inhibition of cerebral monocyte infiltration in these mice significantly improved liver inflammation associated sickness behaviors. Importantly, in recent work we have found that at an earlier time point, when cerebral monocyte infiltration is not evident in mice with liver inflammation, increased monocyte:cerebral endothelial cell adhesive interactions are observed using intravital microscopy of the brain. These monocyte:cerebral endothelial cell adhesive interactions are P-selectin mediated, and inhibition of these interactions attenuated microglial activation and sickness behavior development. Delineating the pathways that the periphery uses to communicate with the brain during inflammatory liver diseases, and the central neurotransmitter systems that are altered through these communication pathways (e.g., serotonin, corticotrophin releasing hormone) to give rise to liver inflammation-associated sickness behaviors, will allow for the identification of novel therapeutic targets to decrease the burden of debilitating symptoms in these patients.

P-selectin-mediated monocyte-cerebral endothelium adhesive interactions link peripheral organ inflammation to sickness behaviors

Sickness behaviors, such as fatigue, mood alterations, and cognitive dysfunction, which result from changes in central neurotransmission, are prevalent in systemic inflammatory diseases and greatly impact patient quality of life. Although, microglia (resident cerebral immune cells) and cytokines (e.g., TNFα) are associated with changes in central neurotransmission, the link between peripheral organ inflammation, circulating cytokine signaling, and microglial activation remains poorly understood. Here we demonstrate, using cerebral intravital microscopy, that in response to liver inflammation, there is increased monocyte specific rolling and adhesion along cerebral endothelial cells (CECs). Peripheral TNFα-TNFR1 signaling and the adhesion molecule P-selectin are central mediators of these monocyte-CEC adhesive interactions which were found to be closely associated with microglial activation, decreased central neural excitability and sickness behavior development. Similar monocyte-CEC adhesive interactions were also observed in another mouse model of peripheral organ inflammation (i.e., 2,4-dinitrobenzene sulfonic acid-induced colitis). Our observations provide a clear link between peripheral organ inflammation and cerebral changes that impact behavior, which can potentially allow for novel therapeutic interventions in patients with systemic inflammatory diseases.

Exploration of a symptoms experience in people with obesity-related nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a highly prevalent condition strongly associated with obesity that can result in premature death. Little is known about the symptoms experience in this progressive disease, preventing health care providers from intervening in the early stages.

PURPOSE

This study explicated symptoms in persons with NAFLD at higher risk of disease progression defined as the presence of one or two copies of the PNPLA3 (rs738409)-G allele.

METHOD

Guided by the Symptoms Experience Model, 42 persons older than 21 years of age with diagnosed NAFLD were recruited from Western Michigan specialty offices in this cross-sectional descriptive study design. The Memorial Symptom Assessment Scale was used to measure the symptoms experience.

DISCUSSION

Participants (97%) experienced 1 or more symptoms (average number of symptoms 12.02, standard deviation = 8.817). There was no statistically significant relationship between symptoms and the PNPLA3 (rs738409) variants. Significant predictors of mean frequency, severity, and distress of symptoms (the Total Memorial Symptom Scale) (F[15, 25] = 2.609, p = .016) were identified.

CONCLUSION

People with NAFLD experience an average of 12 symptoms.

Probiotic Lactobacillus reuteri attenuates the stressor-enhanced severity of Citrobacter rodentium infection

Stressor exposure has been shown to enhance host susceptibility and the severity of a plethora of illnesses, including gastrointestinal disease. In mice, susceptibility to Citrobacter rodentium has been shown to be dependent on host genetics as well as the composition of the intestinal microbiota, but the effects of stressor exposure on this gastrointestinal pathogen have not been elucidated fully. Previously, our lab showed that exposure to the prolonged-restraint stressor prior to a challenge with C. rodentium alters the intestinal microbiota community structure, including a reduction of beneficial genera such as Lactobacillus, which may contribute to stressor-enhanced C. rodentium-induced infectious colitis. To test the effects of stressor exposure on C. rodentium infection, we exposed resistant mice to a prolonged-restraint stressor concurrent with pathogen challenge. Exposure to prolonged restraint significantly enhanced C. rodentium-induced infectious colitis in resistant mice, as measured by increases in colonic histopathology, colonic inflammatory mediator gene production, and pathogen translocation from the colon to the spleen. It was further tested if the beneficial bacterium Lactobacillus reuteri could reduce the stressor-enhanced susceptibility to C. rodentium-enhanced infectious colitis. While L. reuteri treatment did not reduce all aspects of stressor-enhanced infectious colitis, it did significantly reduce pathogen translocation from the colon to the spleen. Taken together, these data demonstrate the deleterious effects that prolonged stressor exposure can have at the onset of a gastrointestinal infection by its ability to render a resistant mouse highly susceptible to C. rodentium. Probiotic treatment ameliorated the systemic manifestations of stress on colonic infection.

In vitro antioxidant capacity and anti-inflammatory activity of seven common oats

Oats are gaining increasing scientific and public interest for their purported antioxidant-associated health benefits. Most reported studies focused on specific oat extracts or particular oat components, such as β-glucans, tocols (vitamin E), or avenanthramides. Studies on whole oats with respect to antioxidant and anti-inflammatory activities are still lacking. Here the antioxidant and anti-inflammatory activities from whole oat groats of seven common varieties were evaluated. All oat varieties had very similar oxygen radical absorption capacity compared with other whole grains. In an anti-inflammatory assay, oat variety CDC Dancer inhibited tumor necrosis factor-α induced nuclear factor-kappa B activation by 27.5% at 2 mg/ml, whereas variety Deiter showed 13.7% inhibition at a comparable dose. Avenanthramide levels did not correlate with the observed antioxidant and anti-inflammatory activities. Further investigations are needed to pinpoint the specific antioxidant and anti-inflammatory compounds, and potential synergistic and/or matrix effects that may help explain the mechanisms of oat's anti-inflammatory actions.