Non-alcoholic fatty liver disease (NAFLD) as a neglected metabolic companion of psychiatric disorders: common pathways and future approaches

Current considerations for clinical management and care of non-alcoholic fatty liver disease: Insights from the 1st International Workshop of the Canadian NASH Network (CanNASH)

Non-alcoholic fatty liver disease (NAFLD) affects approximately 8 million Canadians. NAFLD refers to a disease spectrum ranging from bland steatosis to non-alcoholic steatohepatitis (NASH). Nearly 25% of patients with NAFLD develop NASH, which can progress to liver cirrhosis and related end-stage complications. Type 2 diabetes and obesity represent the main risk factors for the disease. The Canadian NASH Network is a national collaborative organization of health care professionals and researchers with a primary interest in enhancing understanding, care, education, and research around NAFLD, with a vision of best practices for this disease state. At the 1st International Workshop of the CanNASH network in April 2021, a joint event with the single topic conference of the Canadian Association for the Study of the Liver (CASL), clinicians, epidemiologists, basic scientists, and community members came together to share their work under the theme of NASH. This symposium also marked the initiation of collaborations between Canadian and other key opinion leaders in the field representative of international liver associations. The main objective is to develop a policy framework that outlines specific targets, suggested activities, and evidence-based best practices to guide provincial, territorial, and federal organizations in developing multidisciplinary models of care and strategies to address this epidemic.

Severe Hepatic Steatosis Is Associated With Low-Level Viremia and Advanced Fibrosis in Patients With Chronic Hepatitis B in North America

Background and Aims

The obesity epidemic has increased the risk of nonalcoholic fatty liver disease (NAFLD) in both the general and chronic hepatitis B (CHB) populations. Our study aims to determine the prevalence of NAFLD in patients with CHB based on controlled attenuation parameter (CAP) and the epidemiological, clinical, and virological factors associated with severe hepatic steatosis.

Methods

The Canadian Hepatitis B Network cohort was utilized to provide a cross-sectional description of demographics, comorbidities, antiviral treatment, and hepatits B virus (HBV) tests. Liver fibrosis and steatosis were measured by transient elastography and CAP, respectively. Any grade and severe steatosis were defined as CAP >248 and >280 dB/m, respectively. Advanced liver fibrosis was defined as transient elastography measurement >10.7 kPa.

Results

In 1178 patients with CHB (median age: 47.4%, 57.7% males, 75.7% Asian, 13% African, 6.5% White, 86% HBV e antigen negative, median HBV DNA of 2.44 log10IU/mL, 42.7% receiving treatment), the prevalence of any grade and severe steatosis was 53% and 36%, respectively. In the multivariate analysis, obesity was a significant predictor for severe steatosis (adjusted odds ratio: 5.046, 95% confidence interval: 1.22-20.93). Severe steatosis was a determinant associated with viral load (adjusted odds ratio: 0.385, 95% confidence interval: 0.20-0.75, P < .01; r = -0.096, P = .007) regardless of antiviral therapy, age, and alanine aminotransferase levels.

Conclusion

In this large multiethnic CHB population, hepatic steatosis is common. Severe steatosis is independently associated with higher fibrosis, but negatively with HBV DNA, regardless of antiviral therapy history.

Non-alcoholic Fatty Liver Disease and Depression: Evidence for Genotype × Environment Interaction in Mexican Americans

This study examines the impact of G × E interaction effects on non-alcoholic fatty liver disease (NAFLD) among Mexican Americans in the Rio Grande Valley (RGV) of South Texas. We examined potential G × E interaction using variance components models and likelihood-based statistical inference in the phenotypic expression of NAFLD, including hepatic steatosis and hepatic fibrosis (identified using vibration controlled transient elastography and controlled attenuation parameter measured by the FibroScan Device). We screened for depression using the Beck Depression Inventory-II (BDI-II). We identified significant G × E interactions for hepatic fibrosis × BDI-II. These findings provide evidence that genetic factors interact with depression to influence the expression of hepatic fibrosis.

Post-liver transplant outcomes in patients with major psychiatric diagnosis in the United States

INTRODUCTION AND OBJECTIVES

Higher rates of psychiatric disorders are reported among cirrhotic patients. This study examines the demographic and clinical outcomes post-liver transplant (LT) among cirrhotic patients with a major psychiatric diagnosis (cases) compared to those without psychiatric diagnosis (controls).

MATERIALS AND METHODS

Retrospective case control design was used among 189 cirrhotic patients who had undergone LT at Methodist University Hospital Transplant Institute, Memphis, TN between January 2006 and December 2014. Multivariable regression and Cox proportional hazard regression were conducted to compare allograft loss and all-cause mortality.

RESULTS

The study sample consisted of a matched cohort of 95 cases and 94 controls with LT. Females and those with Hepatic Encephalopathy (HE) were more likely to have psychiatric diagnosis. Patients with hepatocellular carcinoma (HCC) were twice as likely to have allograft loss. Psychiatric patients with HCC had two and a half times (HR 2.54; 95% CI: 1.20-5.37; p = 0.015) likelihood of all-cause mortality. Data censored at 1-year post-LT revealed that patients with psychiatric diagnosis have a three to four times higher hazard for allograft loss and all-cause mortality compared to controls after adjusting for covariates, whereas when the data is censored at 5 year, allograft loss and all-cause mortality have two times higher hazard ratio.

CONCLUSIONS

The Cox proportional hazard regression analysis of censored data at 1 and 5 year indicate higher allograft loss and all-cause mortality among LT patients with psychiatric diagnosis. Patients with well-controlled psychiatric disorders who undergo LT need close monitoring and medication adherence.

Non-alcoholic fatty liver disease: A patient guideline

This patient guideline is intended for all patients at risk of or living with non-alcoholic fatty liver disease (NAFLD). NAFLD is the most frequent chronic liver disease worldwide and comes with a high disease burden. Yet, there is a lot of unawareness. Furthermore, many aspects of the disease are still to be unravelled, which has an important impact on the information that is given (or not) to patients. Its management requires a close interaction between patients and their many healthcare providers. It is important for patients to develop a full understanding of NAFLD in order to enable them to take an active role in their disease management. This guide summarises the current knowledge relevant to NAFLD and its management. It has been developed by patients, patient representatives, clinicians and scientists and is based on current scientific recommendations, intended to support patients in making informed decisions.

Every Night and Every Morn: Effect of Variation in CLOCK Gene on Depression Depends on Exposure to Early and Recent Stress

The role of circadian dysregulation is increasingly acknowledged in the background of depressive symptoms, and is also a promising treatment target. Similarly, stress shows a complex relationship with the circadian system. The CLOCK gene, encoding a key element in circadian regulation has been implicated in previous candidate variant studies in depression with contradictory findings, and only a few such studies considered the interacting effects of stress. We investigated the effect of CLOCK variation with a linkage-disequilibrium-based clumping method, in interaction with childhood adversities and recent negative life events, on two phenotypes of depression, lifetime depression and current depressive symptoms in a general population sample. Methods: Participants in NewMood study completed questionnaires assessing childhood adversities and recent negative life events, the Brief Symptom Inventory to assess current depressive symptoms, provided data on lifetime depression, and were genotyped for 1054 SNPs in the CLOCK gene, 370 of which survived quality control and were entered into linear and logistic regression models with current depressive symptoms and lifetime depression as the outcome variable, and childhood adversities or recent life events as interaction variables followed by a linkage disequilibrium-based clumping process to identify clumps of SNPs with a significant main or interaction effect. Results: No significant clumps with a main effect were found. In interaction with recent life events a significant clump containing 94 SNPs with top SNP rs6825994 for dominant and rs6850524 for additive models on current depression was identified, while in interaction with childhood adversities on current depressive symptoms, two clumps, both containing 9 SNPs were found with top SNPs rs6828454 and rs711533. Conclusion: Our findings suggest that CLOCK contributes to depressive symptoms, but via mediating the effects of early adversities and recent stressors. Given the increasing burden on circadian rhythmicity in the modern lifestyle and our expanding insight into the contribution of circadian disruption in depression especially as a possible mediator of stress, our results may pave the way for identifying those who would be at an increased risk for depressogenic effects of circadian dysregulation in association with stress as well as new molecular targets for intervention in stress-related psychopathologies in mood disorders.

Sodium butyrate ameliorates non-alcoholic fatty liver disease by upregulating miR-150 to suppress CXCR4 expression

Sodium butyrate (NaB) in the gut of animals possesses the potential to modulate lipid metabolism, regulate innate immunity and protect intestinal health. Accumulating data have supported the important function of metabolites of intestinal microflora (MIM) in non-alcoholic fatty liver disease (NAFLD). This study intended to investigate the role of NaB in NAFLD and its specific mechanism. Mice were fed a high-fat diet (HFD) for 16 weeks to establish the NAFLD mouse model. The mice were intragastrically administrated MIM (200 µL/day) or NaB (200 mg/kg/day) by gavage for another 8 weeks. The morphology of liver tissues was observed by hematoxylin and eosin (H&E) staining, and the lipid deposition of liver tissues was examined by oil red O staining. The NAFLD cell model was constructed in alpha mouse liver 12 (AML12) cells by 24 hours of stimulation with 0.5 mM free fatty acids. After treatment with 10 mM NaB, AML12 cells were transfected with mimic-miR-150 or inhibitor-miR-150. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting were used to measure the contents of interleukin 1β (IL-1β), IL-6 and tumour necrosis factor α (TNF-α) and the expression of microRNA (miR)-150 and CXCR4 in liver tissues of mice and in AML12 cells. A luciferase reporter assay was applied to verify the binding relationship between miR-150 and CXCR4. The H&E and oil red O staining results showed hepatic steatosis in the liver tissues of HFD-fed mice. There were elevated contents of triacylglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), fasting blood glucose, enhanced activities of alanine aminotransferase(ALT) and aspartate aminotransferase(AST), increased homeostatic model assessment of insulin resistance scores and increased inflammatory responses in the serum of HFD-fed mice. However, intervention with MIM or NaB reversed the above trends, indicating that MIM or NaB intervention relieved hepatic steatosis in mice. HFD-fed mice had downregulated expression of miR-150, whereas the expression level was upregulated after MIM or NaB treatment. Sodium butyrate attenuated NAFLD progression by regulating miR-150. MiR-150 can negatively target CXCR4. Sodium butyrate mitigates HFD-induced NAFLD in mice by upregulating miR-150 expression to downregulate CXCR4.

Lithium therapy and weight change in people with bipolar disorder: A systematic review and meta-analysis

Lithium remains the gold standard maintenance treatment for Bipolar Disorder (BD). However, weight gain is a side effect of increasing relevance due to its metabolic implications. We conducted a systematic review and meta-analysis aimed at summarizing evidence on the use of lithium and weight change in BD. We followed the PRISMA methodology, searching Pubmed, Scopus and Web of Science. From 1003 screened references, 20 studies were included in the systematic review and 9 included in the meta-analysis. In line with the studies included in the systematic review, the meta-analysis revealed that weight gain with lithium was not significant, noting a weight increase of 0.462 Kg (p = 0158). A shorter duration of treatment was significantly associated with more weight gain. Compared to placebo, there were no significant differences in weight gain. Weight gain was significantly lower with lithium than with active comparators. This work reveals a low impact of lithium on weight change, especially compared to some of the most widely used active comparators. Our results could impact clinical decisions.

Population-based body-brain mapping links brain morphology with anthropometrics and body composition

Understanding complex body-brain processes and the interplay between adipose tissue and brain health is important for understanding comorbidity between psychiatric and cardiometabolic disorders. We investigated associations between brain structure and anthropometric and body composition measures using brain magnetic resonance imaging (MRI; n = 24,728) and body MRI (n = 4973) of generally healthy participants in the UK Biobank. We derived regional and global measures of brain morphometry using FreeSurfer and tested their association with (i) anthropometric measures, and (ii) adipose and muscle tissue measured from body MRI. We identified several significant associations with small effect sizes. Anthropometric measures showed negative, nonlinear, associations with cerebellar/cortical gray matter, and brain stem structures, and positive associations with ventricular volumes. Subcortical structures exhibited mixed effect directionality, with strongest positive association for accumbens. Adipose tissue measures, including liver fat and muscle fat infiltration, were negatively associated with cortical/cerebellum structures, while total thigh muscle volume was positively associated with brain stem and accumbens. Regional investigations of cortical area, thickness, and volume indicated widespread and largely negative associations with anthropometric and adipose tissue measures, with an opposite pattern for thigh muscle volume. Self-reported diabetes, hypertension, or hypercholesterolemia were associated with brain structure. The findings provide new insight into physiological body-brain associations suggestive of shared mechanisms between cardiometabolic risk factors and brain health. Whereas the causality needs to be determined, the observed patterns of body-brain relationships provide a foundation for understanding the underlying mechanisms linking psychiatric disorders with obesity and cardiovascular disease, with potential for the development of new prevention strategies.

Major Depressive Disorder in Older Patients as an Inflammatory Disorder: Implications for the Pharmacological Management of Geriatric Depression

Depression is a common and highly disabling condition in older adults. It is a heterogenous disorder and there is emerging evidence of a link between inflammation and depression in older patients, with a possible inflammatory subtype of depression. Persistent low-level inflammation, from several sources including psychological distress and chronic disease, can disrupt monoaminergic and glutaminergic systems to create dysfunctional brain networks. Despite the evidence for the role of inflammation in depression, there is insufficient evidence to recommend use of any putative anti-inflammatory agent in the treatment of depression in older adults at this stage. Further characterisation of markers of inflammation and stratification of participants with elevated rates of inflammatory markers in treatment trials is needed.

Probiotics as a Treatment for "Metabolic Depression"? A Rationale for Future Studies

Depression and metabolic diseases often coexist, having several features in common, e.g., chronic low-grade inflammation and intestinal dysbiosis. Different microbiota interventions have been proposed to be used as a treatment for these disorders. In the paper, we review the efficacy of probiotics in depressive disorders, obesity, metabolic syndrome and its liver equivalent based on the published experimental studies, clinical trials and meta-analyses. Probiotics seem to be effective in reducing depressive symptoms when administered in addition to antidepressants. Additionally, probiotics intake may ameliorate some of the clinical components of metabolic diseases. However, standardized methodology regarding probiotics use in clinical trials has not been established yet. In this narrative review, we discuss current knowledge on the recently used methodology with its strengths and limitations and propose criteria that may be implemented to create a new study of the effectiveness of probiotics in depressive disorders comorbid with metabolic abnormalities. We put across our choice on type of study population, probiotics genus, strains, dosages and formulations, intervention period, as well as primary and secondary outcome measures.

Nutrition-based interventions for mood disorders

Introduction: 'Nutritional Psychiatry' is an emerging area of research that has great potential as an adjunctive tool for the prevention and treatment of diverse neuropsychiatric disorders. Several nutrition-related aspects, such as obesity, dietary patterns, gut microbiome composition and gut permeability, bioactive food compounds, and nutrients can influence pathways implicated in the pathophysiology of mood disorders.Areas covered: Here, the authors review the current evidence on nutrition-mood interaction and nutrition-based treatments for the two main mood disorders, i.e., major depressive disorder and bipolar disorder.Expert opinion: Consistent evidence from observational studies has pointed out the association between a 'healthy' diet, generally characterized by a higher intake of fruits, vegetables, legumes, nuts, whole grains, and good quality sources of protein (i.e. fish and/or seafood), and decreased risk of mood disorders and the parallel association between a 'Western' diet pattern and increased risk. However, only a few clinical trials have evaluated the effect of nutritional interventions on the treatment of these conditions. The bidirectional interaction between the brain and the gut, named 'brain-gut-microbiome axis' or 'gut-brain axis', plays a key role in the link between nutrition and mood disorders. Therefore, nutrition-based strategies for gut microbiota modulation are promising fields in mood disorders.

Plasma Arginase-1 Level Is Associated with the Mental Status of Outpatients with Chronic Liver Disease

While plasma arginase-1 has been suggested as a biomarker of mental status in healthy individuals, it has not been evaluated in patients with chronic liver disease. This cross-sectional study investigated the utility of plasma arginase-1 for screening mental status in patients with chronic liver disease. This study included outpatients with chronic liver disease who underwent regular check-ups at Okayama University Hospital between September 2018 and January 2019. In addition to the standard blood tests, the plasma arginase-1 level was analyzed. The patients’ mental status was assessed using the Japanese version of the General Health Questionnaire-28 (GHQ-28). The associations between mental status and various parameters, including plasma arginase-1, were investigated using logistic regression analysis. Among 114 participating patients, 8 were excluded, comprising 6 with insufficient blood samples for plasma arginase-1 measurement and 2 with incomplete questionnaires. Multivariate binomial logistic regression analysis revealed that plasma arginase-1 was significantly and negatively associated with the GHQ-total score, especially somatic symptoms. Therefore, plasma arginase-1 may be a useful biomarker for assessing the mental status of outpatients with chronic liver disease.

Insights into the Impact of Microbiota in the Treatment of NAFLD/NASH and Its Potential as a Biomarker for Prognosis and Diagnosis

Non-alcoholic fatty liver disease (NAFLD) is an increasing cause of chronic liver illness associated with obesity and metabolic disorders, such as hypertension, dyslipidemia, or type 2 diabetes mellitus. A more severe type of NAFLD, non-alcoholic steatohepatitis (NASH), is considered an ongoing global health threat and dramatically increases the risks of cirrhosis, liver failure, and hepatocellular carcinoma. Several reports have demonstrated that liver steatosis is associated with the elevation of certain clinical and biochemical markers but with low predictive potential. In addition, current imaging methods are inaccurate and inadequate for quantification of liver steatosis and do not distinguish clearly between the microvesicular and the macrovesicular types. On the other hand, an unhealthy status usually presents an altered gut microbiota, associated with the loss of its functions. Indeed, NAFLD pathophysiology has been linked to lower microbial diversity and a weakened intestinal barrier, exposing the host to bacterial components and stimulating pathways of immune defense and inflammation via toll-like receptor signaling. Moreover, this activation of inflammation in hepatocytes induces progression from simple steatosis to NASH. In the present review, we aim to: (a) summarize studies on both human and animals addressed to determine the impact of alterations in gut microbiota in NASH; (b) evaluate the potential role of such alterations as biomarkers for prognosis and diagnosis of this disorder; and (c) discuss the involvement of microbiota in the current treatment for NAFLD/NASH (i.e., bariatric surgery, physical exercise and lifestyle, diet, probiotics and prebiotics, and fecal microbiota transplantation).

Degree Adjusted Large-Scale Network Analysis Reveals Novel Putative Metabolic Disease Genes

Simple Summary

To explore some of the low-degree but topologically important nodes in the Metabolic disease (MD) network, we propose a background-corrected betweenness centrality (BC) and identify 16 novel candidates likely to play a role in MD. MD specific protein–protein interaction networks (PPINs) were constructed using two known databasesHuman Protein Reference Database (HPRD) and BioGRID. The identified candidates have been found to play a role in diverse conditions including co-morbidities of MD, neurological and immune system-related conditions.

Abstract

A large percentage of the global population is currently afflicted by metabolic diseases (MD), and the incidence is likely to double in the next decades. MD associated co-morbidities such as non-alcoholic fatty liver disease (NAFLD) and cardiomyopathy contribute significantly to impaired health. MD are complex, polygenic, with many genes involved in its aetiology. A popular approach to investigate genetic contributions to disease aetiology is biological network analysis. However, data dependence introduces a bias (noise, false positives, over-publication) in the outcome. While several approaches have been proposed to overcome these biases, many of them have constraints, including data integration issues, dependence on arbitrary parameters, database dependent outcomes, and computational complexity. Network topology is also a critical factor affecting the outcomes. Here, we propose a simple, parameter-free method, that takes into account database dependence and network topology, to identify central genes in the MD network. Among them, we infer novel candidates that have not yet been annotated as MD genes and show their relevance by highlighting their differential expression in public datasets and carefully examining the literature. The method contributes to uncovering connections in the MD mechanisms and highlights several candidates for in-depth study of their contribution to MD and its co-morbidities.

Renaming NAFLD to MAFLD: Could the LDE System Assist in This Transition?

Our understanding of fatty liver syndromes and their relationship with the metabolic syndrome has improved over recent decades and, paralleling this, we are now at the dawn of the NAFLD (nonalcoholic fatty liver disease) to MAFLD (metabolic-associated fatty liver disease) transition. The pitfalls of NAFLD diagnosis, together with disappointing results in therapeutic trials, and the inconsistencies and risks inherent in a "negative" definition (such as "nonalcoholic") as opposed to a "positive" one (i.e., "metabolic") are predicted to facilitate the proposed renaming of NAFLD to MAFLD. However, a premature change of terminology would not necessarily address major unmet needs in this area, and may even become counterproductive. As an aid to selecting more homogeneous cohorts of patients, I propose the LDE (Liver, Determinants, Extra-hepatic) classification system which, in principle, may help to assess the natural course of disease as well as the efficacy of novel drugs in patients with NAFLD/MAFLD.

Construction and analysis of protein-protein interaction network of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a disease with multidimensional complexities. Many attempts have been made over the years to treat this disease but its incidence is rising. For this reason, the need to identify and study new candidate proteins that may be associated with NAFLD is of utmost importance. Systems-based approaches such as the analysis of protein-protein interaction (PPI) network could lead to the discovery of new proteins associated with a disease that can then be translated into clinical practice. The aim of this study is to analyze the interaction network of human proteins associated with NAFLD as well as their experimentally verified interactors and to identify novel associations with other human proteins that may be involved in this disease. Computational analysis made it feasible to detect 77 candidate proteins associated with NAFLD, having high network scores. Furthermore, clustering analysis was performed to identify densely connected regions with biological significance in this network. Additionally, gene expression analysis was conducted to validate part of the findings of this research work. We believe that our research will be helpful in extending experimental efforts to address the pathogenesis and progression of NAFLD.

Understanding Mechanisms Underlying Non-Alcoholic Fatty Liver Disease (NAFLD) in Mental Illness: Risperidone and Olanzapine Alter the Hepatic Proteomic Signature in Mice

Patients with severe mental illness have increased mortality, often linked to cardio-metabolic disease. Non-alcoholic fatty liver disease (NAFLD) incidence is higher in patients with schizophrenia and is exacerbated with antipsychotic treatment. NAFLD is associated with obesity and insulin resistance, both of which are induced by several antipsychotic medications. NAFLD is considered an independent risk factor for cardiovascular disease, the leading cause of death for patients with severe mental illness. Although the clinical literature clearly defines increased risk of NAFLD with antipsychotic therapy, the underlying mechanisms are not understood. Given the complexity of the disorder as well as the complex pharmacology associated with atypical antipsychotic (AA) medications, we chose to use a proteomic approach in healthy mice treated with a low dose of risperidone (RIS) or olanzapine (OLAN) for 28 days to determine effects on development of NAFLD and to identify pathways impacted by AA medications, while removing confounding intrinsic effects of mental illness. Both AA drugs caused development of steatosis in comparison with vehicle controls (p < 0.01) and affected multiple pathways relating to energy metabolism, NAFLD, and immune function. AA-associated alteration in autonomic function appears to be a unifying theme in the regulation of hepatic pathology.