Evaluation of Biomarkers of NAFLD in a Cohort of Morbidly Obese Patients

Higher pNRF2, SOCS3, IRF3, and RIG1 Tissue Protein Expression in NASH Patients versus NAFL Patients: pNRF2 Expression Is Concomitantly Associated with Elevated Fasting Glucose Levels

Non-alcoholic fatty liver disease (NAFLD) embraces simple steatosis in non-alcoholic fatty liver (NAFL) to advanced non-alcoholic steatohepatitis (NASH) associated with inflammation, fibrosis, and cirrhosis. NAFLD patients often have metabolic syndrome and high risks of cardiovascular and liver-related mortality. Our aim was to clarify which proteins play a role in the progression of NAFL to NASH. The study investigates paraffin-embedded samples of 22 NAFL and 33 NASH patients. To detect potential candidates, samples were analyzed by immunohistochemistry for the proteins involved in innate immune regulation, autophagy, apoptosis, and antioxidant defense: IRF3, RIG-1, SOCS3, pSTAT3, STX17, SGLT2, Ki67, M30, Caspase 3, and pNRF2. The expression of pNRF2 immunopositive nuclei and SOCS3 cytoplasmic staining were higher in NASH than in NAFL (p = 0.001); pNRF2 was associated with elevated fasting glucose levels. SOCS3 immunopositivity correlated positively with RIG1 (r = 0.765; p = 0.001). Further, in NASH bile ducts showed stronger IRF3 immunostaining than in NAFL (p = 0.002); immunopositive RIG1 tissue was higher in NASH than in NAFL (p = 0.01). Our results indicate that pNRF2, SOCS3, IRF3, and RIG1 are involved in hepatic lipid metabolism. We suggest that they may be suitable for further studies to assess their potential as therapeutics.

Effects of Orlistat or Telmisartan on the Serum Free Fatty Acids in Non-alcoholic Fatty Liver Disease Patients: An Open-Labeled Randomized Controlled Study

BACKGROUND

One of the important inducers of inflammatory responses and accumulation of fat in hepatocytes is free fatty acids which ultimately lead to the development of non-alcoholic fatty liver disease. Patients with non-alcoholic fatty liver disease have high levels of plasma free fatty acids which are usually associated with type 2 diabetes and components of metabolic syndrome including dyslipidemia. Objective of this research is to investigate the effects of orlistat (a lipase enzyme inhibitor) or telmisartan (an angiotensin receptor blocker) on the serum free fatty acids in non-alcoholic fatty liver disease patients taking into consideration the baseline lipid profile.

METHODS

This open-label clinical trial was carried out in the Department of Pharmacology, College of Medicine at the University of Sulaimani in cooperation with Shar Teaching Hospital in Sulaimani city-Kurdistan Region of Iraq. A total number of 74 non-alcoholic fatty liver disease patients were recruited and grouped randomly into group I (n = 25) treated with orlistat (120 mg/day orally) for 12 weeks, group II (n = 24) treated with telmisartan (20 mg/day orally) for 8 weeks, and group III (n = 25) treated with placebo (carboxy- methyl cellulose) once daily. Fasting serum level of free fatty acid and lipid profile including total cholesterol, triglyceride, high-density lipoprotein, and non-high-density lipoproteins were determined.

RESULTS

Orlistat and telmisartan significantly reduced the triglyceride-glucose index and free fatty acid levels (P < .001) in patients with non-alcoholic fatty liver diseases.

CONCLUSION

Short-term treatment with orlistat or telmisartan produce effective and significant reductions in FFAs in patients with non-alcoholic fatty liver disease compared to placebo. Orlistat effectively reduces the free fatty acid irrespective of the baseline lipid profile.

Significance of Simple Steatosis: An Update on the Clinical and Molecular Evidence

Non-alcoholic fatty liver disease (NAFLD) is defined clinicopathologically by the accumulation of lipids in >5% of hepatocytes and the exclusion of secondary causes of fat accumulation. NAFLD encompasses a wide spectrum of liver damage, extending from simple steatosis or non-alcoholic fatty liver (NAFL) to non-alcoholic steatohepatitis (NASH)—the latter is characterized by inflammation and hepatocyte ballooning degeneration, in addition to the steatosis, with or without fibrosis. NAFLD is now the most common cause of chronic liver disease in Western countries and affects around one quarter of the general population. It is a multisystem disorder, which is associated with an increased risk of type 2 diabetes mellitus as well as liver- and cardiovascular-related mortality. Although earlier studies had suggested that NAFL is benign (i.e., non-progressive), cumulative evidence challenges this dogma, and recent data suggest that nearly 25% of those with NAFL may develop fibrosis. Importantly, NAFLD patients are more susceptible to the toxic effects of alcohol, drugs, and other insults to the liver. This is likely due to the functional impairment of steatotic hepatocytes, which is virtually undetectable by current clinical tests. This review provides an overview of the current evidence on the clinical significance of NAFL and discusses the molecular basis for NAFL development and progression.

Characterization of two types of intranuclear hepatocellular inclusions in NAFLD

Nuclear inclusions (NI) are a common finding in hepatocytes from patients with liver disease especially in diabetes mellitus and non-alcoholic fatty liver disease (NAFLD) but studies examining the shape and content of these inclusions in detail are lacking. In this study we define two distinct types of NI in NAFLD: inclusions bounded by the nuclear membrane, containing degenerative cell organelles and heterolysosomes (type1) and inclusions with deposits of glycogen but without any kind of organelles and delimiting membrane (type2). NI in 77 paraffin-embedded patients of NAFLD including NAFL and non-alcoholic steatohepatitis (NASH) were analyzed. In 4–12% of type1 NI immunopositivity for the autophagy-associated proteins LC3B, ubiquitin, p62/sequestosome1, cathepsin D and cathepsin B were detected with co-localizations of ubiquitin and p62; type2 NI showed no immunoreactivity. Three-dimensional reconstructions of isolated nuclei revealed that NI type1 are completely enclosed within the nucleus, suggesting that NI, although probably derived from cytoplasmic invaginations, are not just simple invaginations. Our study demonstrates two morphologically different types of inclusions in NAFLD, whereby both gained significantly in number in advanced stages. We suggest that the presence of autophagy-associated proteins and degenerated organelles within type1 NI plays a role in disease progression.

Liver parameters as part of a non-invasive model for prediction of all-cause mortality after myocardial infarction

INTRODUCTION

Liver parameters are associated with cardiovascular disease risk and severity of stenosis. It is unclear whether liver parameters could predict the long-term outcome of patients after acute myocardial infarction (AMI). We performed an unbiased analysis of the predictive value of serum parameters for long-term prognosis after AMI.

MATERIAL AND METHODS

In a retrospective, observational, single-center, cohort study, 569 patients after AMI were enrolled and followed up until 6 years for major adverse cardiovascular events, including cardiac death. Patients were classified into non-survivors (n = 156) and survivors (n = 413). Demographic and laboratory data were analyzed using ensemble feature selection (EFS) and logistic regression. Correlations were performed for serum parameters.

RESULTS

Age (73; 64; p < 0.01), alanine aminotransferase (ALT; 93 U/l; 40 U/l; p < 0.01), aspartate aminotransferase (AST; 162 U/l; 66 U/l; p < 0.01), C-reactive protein (CRP; 4.7 U/l; 1.6 U/l; p < 0.01), creatinine (1.6; 1.3; p < 0.01), γ-glutamyltransferase (GGT; 71 U/l; 46 U/l; p < 0.01), urea (29.5; 20.5; p < 0.01), estimated glomerular filtration rate (eGFR; 49.6; 61.4; p < 0.01), troponin (13.3; 7.6; p < 0.01), myoglobin (639; 302; p < 0.01), and cardiovascular risk factors (hypercholesterolemia p < 0.02, family history p < 0.01, and smoking p < 0.01) differed significantly between non-survivors and survivors. Age, AST, CRP, eGFR, myoglobin, sodium, urea, creatinine, and troponin correlated significantly with death (r = -0.29; 0.14; 0.31; -0.27; 0.20; -0.13; 0.33; 0.24; 0.12). A prediction model was built including age, CRP, eGFR, myoglobin, and urea, achieving an AUROC of 77.6% to predict long-term survival after AMI.

CONCLUSIONS

Non-invasive parameters, including liver and renal markers, can predict long-term outcome of patients after AMI.

Effects of combined therapy with resveratrol, continuous and interval exercises on apoptosis, oxidative stress, and inflammatory biomarkers in the liver of old rats with non-alcoholic fatty liver disease

CONTEXT

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder.

OBJECTIVE

Effects of combined therapy with resveratrol, interval and continuous exercises on oxidative stress, inflammation, and apoptosis in the liver of rats with NAFLD.

METHODS

NAFLD rats were organised in patient, saline, resveratrol (RSV), continuous exercise, interval exercise, continuous exercise + RSV, and interval exercise + RSV groups.

RESULTS

Resveratrol supplementation alone or in combination with interval and continuous training significantly decreased malondialdehyde and TNF-α level (p < .05), while the levels of catalase; superoxide dismutase and IL-10 were significantly increased (p < .05). Although RSV alone significantly decreased the percentage of apoptotic cells (17.12%), its combination with interval (10.74%), and continuous (14.85%) exercise training demonstrated higher anti-apoptotic activity (p < .05).

CONCLUSIONS

Although resveratrol alone has an antioxidant, anti-apoptotic and anti-inflammatory properties, combined therapy with interval, and continuous training can be more effective to mitigate these abnormalities in NAFLD patients.

Non-invasive assessment of NAFLD as systemic disease-A machine learning perspective

Background & aims

Current non-invasive scores for the assessment of severity of non-alcoholic fatty liver disease (NAFLD) and identification of patients with non-alcoholic steatohepatitis (NASH) have insufficient performance to be included in clinical routine. In the current study, we developed a novel machine learning approach to overcome the caveats of existing approaches.

Methods

Non-invasive parameters were selected by an ensemble feature selection (EFS) from a retrospectively collected training cohort of 164 obese individuals (age: 43.5±10.3y; BMI: 54.1±10.1kg/m²) to develop a model able to predict the histological assessed NAFLD activity score (NAS). The model was evaluated in an independent validation cohort (122 patients, age: 45.2±11.75y, BMI: 50.8±8.61kg/m²).

Results

EFS identified age, γGT, HbA1c, adiponectin, and M30 as being highly associated with NAFLD. The model reached a Spearman correlation coefficient with the NAS of 0.46 in the training cohort and was able to differentiate between NAFL (NAS≤4) and NASH (NAS>4) with an AUC of 0.73. In the independent validation cohort, an AUC of 0.7 was achieved for this separation. We further analyzed the potential of the new model for disease monitoring in an obese cohort of 38 patients under lifestyle intervention for one year. While all patients lost weight under intervention, increasing scores were observed in 15 patients. Increasing scores were associated with significantly lower absolute weight loss, lower reduction of waist circumference and basal metabolic rate.

Conclusions

A newly developed model (http://CHek.heiderlab.de) can predict presence or absence of NASH with reasonable performance. The new score could be used to detect NASH and monitor disease progression or therapy response to weight loss interventions.

Effects of resveratrol, exercises and their combination on Farnesoid X receptor, Liver X receptor and Sirtuin 1 gene expression and apoptosis in the liver of elderly rats with nonalcoholic fatty liver

Background

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder. This study aims to consider effects of resveratrol, exercise and their combination on Farnesoid X receptor (Fxr), the liver X receptor (Lxr) and Sirtuin 1 (Sirt 1) genes expression in the liver of elderly rats with NAFLD.

Methods

Rats with NAFLD were randomly divided into seven groups including patient, saline, resveratrol (RSV), interval exercise, continuous exercise, interval exercise + RSV and continuous exercise + RSV. Levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) in the liver tissue were measured using specific ELISA kits. A TUNEL assay kit was used for the assessment of hepatic cells apoptosis. Lipid profiles were considered by measuring the serum triglyceride, cholesterol, LDL, and HDL. Expression of Sirt1, Lxr and Fxr genes was considered using RT-PCR.

Results

Resveratrol administration alone or combined with exercise training significantly improved the expression of Sirt1, Lxr and Fxr genes (p < 0.05) in the hepatic tissue of rats with NAFLD, while levels of AST, ALT, ALP enzymes, as well as apoptotic cells were significantly decreased (p < 0.05).

Discussion

Although resveratrol alone improves the expression of Sirt1, Lxr and Fxr, as well as liver function, combined therapy with exercise training is more effective to improve NAFLD.

SPARC expression is associated with hepatic injury in rodents and humans with non-alcoholic fatty liver disease

Mechanisms that control progression from simple steatosis to steato-hepatitis and fibrosis in patients with non-alcoholic fatty liver disease (NAFLD) are unknown. SPARC, a secreted matricellular protein, is over-expressed in the liver under chronic injury. Contribution of SPARC accumulation to disease severity is largely unknown in NAFLD. We assessed the hypothesis that SPARC is increased in livers with more necrosis and inflammation and could be associated with more fibrosis. qrt-PCR, immunohistochemistry, and ELISA were employed to localize and quantify changes in SPARC in 62 morbidly obese patients with NAFLD/NASH and in a mouse model of diet-induced-NASH. Results were correlated with the severity of NAFLD/NASH. In obese patients 2 subgroups were identified with either high SPARC expression (n = 16) or low SPARC expression (n = 46) in the liver, with a cutoff of 1.2 fold expression. High expression of SPARC paralleled hepatocellular damage and increased mRNA expression of pro-fibrogenic factors in the liver. In line with these findings, in the NASH animal model SPARC knockout mice were protected from inflammatory injury, and showed less inflammation and fibrosis. Hepatic SPARC expression is associated with liver injury and fibrogenic processes in NAFLD. SPARC has potential as preventive or therapeutic target in NAFLD patients.

Investigating Molecular Connections of Non-alcoholic Fatty Liver Disease with Associated Pathological Conditions in West Virginia for Biomarker Analysis

Non-alcoholic fatty liver disease (NAFLD) is a disease characterized by a steatosis of the liver that may progress to more serious pathological conditions including: nonalcoholic steatohepatitis (NASH), fibrosis, and cirrhosis. As the prevalence of NAFLD has increased worldwide in recent years, pathophysiology and risk factors associated with disease progression of NAFLD are at the focus of many studies. NAFLD is related to and shares common serum biomarkers with cardiovascular disease (CVD), type 2 diabetes mellitus (T2DM), obesity, and metabolic syndrome (MetS). West Virginia (WV) is a state with some of the highest rates of CVD, obesity and diabetes mellitus. As NAFLD is closely related to these diseases, it is of particular interest in WV. Currently there is no cost-effective, standardized method used clinically to detect NAFLD prior to the onset of reversible complications. At this time, the diagnosis of NAFLD is made with costly radiologic studies and invasive biopsy. These studies are only diagnostic once changes to hepatic tissue have occurred. The diagnosis of NAFLD by traditional methods may not allow for successful intervention and may not be readily available in areas with already sparse medical resources. In this literature review, we identify a list of biomarkers common among CVD, T2DM, obesity, MetS and NAFLD. From this research we propose the following biomarkers are good candidates for inclusion in a panel of biomarkers for the early detection of NAFLD: adiponectin, AST, ALT, apo-B, CK18, CPS1, CRP, FABP-1, ferritin, GGT, GRP78, HDL-C, IGF-1, IL-1β, 6, 8, 10, IRS-2PAI-1, leptin, lumican, MDA SREBP-1c and TNF-α. Creating and implementing a biomarker panel for the early detection and attenuation of NAFLD, prior to the onset of irreversible complication would provide maximum benefit and decrease the disease burden on the patients and healthcare system of WV.

NON-ALCOHOLIC STEATOHEPATITIS IN PATIENTS WITH OBESITY: INTERCONNECTION BETWEEN BODY MASS, CHANGES OF LIPID METABOLISM AND CONCOMITANT PATHOLOGY OF BILIARY TRACT

Aim – to study the main indices of lipid blood spectrum, which changes lead to DL formation, depending of body mass index (BMI) and concomitant pathology of biliary tract in patients with NASH and obesity. Materials and methods. There were examined 100 patients with NASH in combination with obesity and BT pathology, in which during sonographic or morphological study of bioptat of the liver were revealed the signs of hepatic steatosis. Among patients were 40 men and 60 women. The mean age of patients – (54,68±1,15) years old. The control group included 20 practically healthy persons (PHP). BMI was determined by Quetelet formula. Depending of the degree of BMI increase all patients with NASH and obesity were divided into three groups: 1 group – with BМI 25-29,9 kg/m2 – EBM; 2 group – with BMI 30-34,9 kg/m2 – obesity of I degree; 3 group – with BMI 35-39,9 kg/m2 – obesity of ІІ degree. All examined patients had concomitant pathology from BT side. Depending on BT pathology all patients were also divided into 3 groups: NASH with chronic non-calculous cholecystitis (CNC); NASH with chronic calculous cholecystitis (CCC); NASH in patients after laparoscopic cholecystectomy (LCE) with concomitant postcholecystectomical syndrome (PCES). For characteristic of lipid exchange were determined the general cholesterol (GCS), general lipids (GL), triglycerides (TG), lipoproteins of the low density (LDL), lipoproteins of the high density (HDL). DL phenotype was determined by D.S. Fredrickson classification with modern additions. Results. Analysis of lipid changes in patients with NASH demonstrated the reliable increase of GCS with parallel rise of TG, GL, LDL, fixed at increase of BMI relative to PHP (р<0,05, р<0,001) and to patients of other groups (р<0,05). Maximal values of GCS, TG, GL and also LDL were determined in 2 and 3 groups of observation at obesity of I and II degrees. There was registered the reliable decrease of HDL content in most patients of 3 group relative to the ones of 2 group, (р<0,01) and of 1 one. The level of GCS, TG, GL and LDL was almost equally increased in all groups of observation of NASH: with concomitant CNC, CCC and in patients with PCES relative to PSP, (р<0,001). HDL indices were equally decreased at concomitant CNC and CCC relative to the patients with PCES background with HDL level within physiological norm (р<0,001, рF=0,009). There are separated two main phenotypes of DL: IIa and IIb that were typical for patients with NASH and obesity with BT pathology. It was established, that IIb phenotype of dyslipidemia was most often observed in patients with BMI 30-34,9 kg/m2 and 35-39,9 kg/m2. Discussion. There were determined the features of changes of lipid blood spectrum of in this category of patients that are manifested by variability of disorders from hypercholesterolemia and hypertriglyceridemia on the background of increase of GCS, TG, GL, LDL and decrease of HDL. The progression of lipid disorders in patients with NASH in combination with obesity and BT pathology depends on increase of BMI parameters. The concomitant pathology from BT side partially influenced the indices of lipid blood spectrum. Thus, the low level of HDL in patients with NASH in combination with obesity and concomitant CNC and CCC can be explained by the intense inflammatory processes in BT, attended with disorder of indices of lipid profile with decrease of HDL and increase of GCS, TG, GL, LDL. Conclusion. Progression of intensity of lipid disorders in patients with NASH in combination with obesity and BT pathology depends on increase of BMI parameters. The concomitant BT pathology partially influences the parameters of lipid blood spectrum. HDL was equally decreased in all patients with NASH at CNC and CCC relative to patients with concomitant PCES and HDL level within physiological norm. At NASH in combination with obesity at increase of BMI the DL phenomena more often appear in patients. There are separated two main phenotypes of dyslipidemias: IIa and IIb.

Genome-scale metabolic modelling of hepatocytes reveals serine deficiency in patients with non-alcoholic fatty liver disease

Several liver disorders result from perturbations in the metabolism of hepatocytes, and their underlying mechanisms can be outlined through the use of genome-scale metabolic models (GEMs). Here we reconstruct a consensus GEM for hepatocytes, which we call iHepatocytes2322, that extends previous models by including an extensive description of lipid metabolism. We build iHepatocytes2322 using Human Metabolic Reaction 2.0 database and proteomics data in Human Protein Atlas, which experimentally validates the incorporated reactions. The reconstruction process enables improved annotation of the proteomics data using the network centric view of iHepatocytes2322. We then use iHepatocytes2322 to analyse transcriptomics data obtained from patients with non-alcoholic fatty liver disease. We show that blood concentrations of chondroitin and heparan sulphates are suitable for diagnosing non-alcoholic steatohepatitis and for the staging of non-alcoholic fatty liver disease. Furthermore, we observe serine deficiency in patients with NASH and identify PSPH, SHMT1 and BCAT1 as potential therapeutic targets for the treatment of non-alcoholic steatohepatitis.

Hyaluronic acid as a non-invasive biomarker of liver fibrosis

Chronic liver diseases may cause inflammation and progressive scarring, over time leading to irreversible hepatic damage (cirrhosis). As a result, the need to assess and closely monitor individuals for risk factors of components of matrix deposition and degradation, as well as the severity of the fibrosis using biomarkers, has been increasingly recognized.

AIM

Our aim is to review the use of biomarker for diagnosing and defining the severity of liver fibrosis.

METHODS

A systematic literature review was done using the terms "hyaluronic acid" and "liver fibrosis" as well as the name of each biomarker or algorithm known to be employed. PubMed and Google Scholar were searched, and English language articles indexed between January 2010 and October 2014 in which HA was used as a marker of liver fibrosis were retrieved, regardless of the underlying liver disease. Each author read the publications separately and the results were analyzed and discussed.

RESULTS

Biomarkers offer a potential prognostic or diagnostic indicator for disease manifestation, progression, or both. Serum biomarkers, including HA, have been used for many years. Emerging biomarkers such as metalloproteinases have been proposed as tools that provide valuable complementary information to that obtained from traditional biomarkers. Moreover, markers of extracellular matrix degradation provide powerful predictions of risk. In order for biomarkers to be clinically useful in accurately diagnosing and treating disorders, age-specific reference intervals that account for differences in gender and ethnic origin are a necessity.

CONCLUSIONS

This review attempts to provide a comprehensive analysis of the emerging risk biomarkers of liver fibrosis and to describe the clinical significance and analytical considerations of each biomarker pointing out sentinel features of disease progression.

NLRP3 inflammasome activation is required for fibrosis development in NAFLD

NLR inflammasomes, caspase 1 activation platforms critical for processing key pro-inflammatory cytokines, have been implicated in the development of nonalcoholic fatty liver disease (NAFLD). As the direct role of the NLRP3 inflammasome remains unclear, we tested effects of persistent NLRP3 activation as a contributor to NAFLD development and, in particular, as a modulator of progression from benign hepatic steatosis to steatohepatitis during diet-induced NAFLD. Gain of function tamoxifen-inducible Nlrp3 knock-in mice allowing for in vivo temporal control of NLRP3 activation and loss of function Nlrp3 knockout mice were placed on short-term choline-deficient amino acid-defined (CDAA) diet, to induce isolated hepatic steatosis or long-term CDAA exposure, to induce severe steatohepatitis and fibrosis, respectively. Expression of NLRP3 associated proteins was assessed in liver biopsies of a well-characterized group of patients with the full spectrum of NAFLD. Nlrp3(-/-) mice were protected from long-term feeding CDAA-induced hepatomegaly, liver injury, and infiltration of activated macrophages. More importantly, Nlrp3(-/-) mice showed marked protection from CDAA-induced liver fibrosis. After 4 weeks on CDAA diet, wild-type (WT) animals showed isolated hepatic steatosis while Nlrp3 knock-in mice showed severe liver inflammation, with increased infiltration of activated macrophages and early signs of liver fibrosis. In the liver samples of patients with NAFLD, inflammasome components were significantly increased in those patients with nonalcoholic steatohepatitis (NASH) when compared to those with non-NASH NAFLD with mRNA levels of pro-IL1 beta correlated to levels of COL1A1. Our study uncovers a crucial role for the NLRP3 inflammasome in the development of NAFLD. These findings may lead to novel therapeutic strategies aimed at halting the progression of hepatic steatosis to the more severe forms of this disease. Key message: Mice with NLRP3 inflammasome loss of function are protected from diet-induced steatohepatitis. NLRP3 inflammasome gain of function leads to early and severe onset of diet-induced steatohepatitis in mice. Patients with severe NAFLD exhibit increased levels of NLRP3 inflammasome components and levels of pro-IL1β mRNA correlate with the expression of COL1A1.

The Wide and Complex Field of NAFLD Biomarker Research: Trends

Background. Nonalcoholic fatty liver disease is now acknowledged as a complex public health issue linked to sedentary lifestyle, obesity, and related disorders like type 2 diabetes and metabolic syndrome. Aims. We aimed to retrieve its trends out of the huge amount of published data. Therefore, we conducted an extensive literature search to identify possible biomarker and/or biomarker combinations by retrospectively assessing and evaluating common and novel biomarkers to predict progression and prognosis of obesity related liver diseases. Methodology. We analyzed finally 62 articles accounting for 157 cohorts and 45,288 subjects. Results. Despite the various approaches, most cohorts were considerably small and rarely comparable. Also, we found that the same standard parameters were measured rather than novel biomarkers. Diagnostics approaches appeared incomparable. Conclusions. Further collaborative investigations on harmonizing ways of data acquisition and identifying such biomarkers for clinical use are necessary to yield sufficient significant results of potential biomarkers.

Fetuin-A mRNA expression is elevated in NASH compared with NAFL patients

Fetuin-A is a pro-inflammatory protein expressed by hepatocytes. Its course in morbidly obese patients with NAFLD (non-alcoholic fatty liver disease) following weight loss by BAS (bariatric surgery) has not been fully elucidated yet. In the present study, we prospectively examined the effects of weight loss on various metabolic factors at 4 weeks and 6 months after surgery. Blood and liver tissues were retrieved from 108 morbidly obese NAFLD patients before/during BAS, and 50 of these individuals met the criteria for NASH (non-alcoholic steatohepatitis). Fetuin-A expression was measured by qPCR (quantitative real-time PCR), Western blotting and immunohistochemistry. Hepatocyte apoptosis was quantified via M30 (caspase-cleaved cytokeratin-18 fragments). Plasma concentrations of adiponectin and fetuin-A were determined by ELISA. Serum-derived parameters were additionally taken at 4 weeks and 6 months post-operatively. In addition, primary human hepatocytes were treated with NEFA (non-esterified fatty acid) to investigate changes in fetuin-A. BMI (body mass index) decreased significantly from 53.0±1.1 to 36.4±1.9 kg/m2 in the NAFL group and from 53.3±1.1 to 37.6±1.2 kg/m2 in the NASH group (P<0.0001) at 6 months post-surgery. This was associated with diminishing M30 and M65 (total cytokeratin-18) levels over 6 months after surgery. Adiponectin levels increased continuously in NASH patients, whereas NAFL patients plateaued at 4 weeks post-operatively. Hepatic fetuin-A mRNA and protein expression was elevated before surgery-induced weight loss. However, plasma concentrations of fetuin-A increased signficantly in NASH patients 4 weeks post-operatively. Treatment of hepatocytes with NEFA led to up-regulation of fetuin-A expression. BAS probably has a beneficial effect on NAFLD, as indicated by reduced hepatocyte apoptosis and improved adipokine profiles. In addition, fetuin-A expression is more prominent in NASH.

Novel algorithm for non-invasive assessment of fibrosis in NAFLD

Introduction

Various conditions of liver disease and the downsides of liver biopsy call for a non-invasive option to assess liver fibrosis. A non-invasive score would be especially useful to identify patients with slow advancing fibrotic processes, as in Non-Alcoholic Fatty Liver Disease (NAFLD), which should undergo histological examination for fibrosis.

Patients/Methods

Classic liver serum parameters, hyaluronic acid (HA) and cell death markers of 126 patients undergoing bariatric surgery for morbid obesity were analyzed by machine learning techniques (logistic regression, k-nearest neighbors, linear support vector machines, rule-based systems, decision trees and random forest (RF)). Specificity, sensitivity and accuracy of the evaluated datasets to predict fibrosis were assessed.

Results

None of the single parameters (ALT, AST, M30, M60, HA) did differ significantly between patients with a fibrosis score 1 or 2. However, combining these parameters using RFs reached 79% accuracy in fibrosis prediction with a sensitivity of more than 60% and specificity of 77%. Moreover, RFs identified the cell death markers M30 and M65 as more important for the decision than the classic liver parameters.

Conclusion

On the basis of serum parameters the generation of a fibrosis scoring system seems feasible, even when only marginally fibrotic tissue is available. Prospective evaluation of novel markers, i.e. cell death parameters, should be performed to identify an optimal set of fibrosis predictors.

Free fatty acids repress small heterodimer partner (SHP) activation and adiponectin counteracts bile acid-induced liver injury in superobese patients with nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in industrialized countries and may proceed to steatohepatitis (NASH). Apoptosis and free fatty acid (FFA)-induced lipotoxicity are important features of NASH pathogenesis. We have shown a hepatoprotective effect of adiponectin in steatotic livers of hepatitis C virus (HCV) patients and recent data links bile acid (BA) metabolism to the pathogenesis of NAFLD. The aim of this study was to identify potential interactions between BA and FFA metabolism in NAFLD. Liver biopsies and serum samples from 113 morbidly obese patients receiving bariatric surgery, healthy individuals, and moderately obese NAFLD patients were studied. Serum FFA, BA, and M30 were increased in NASH versus simple steatosis, while adiponectin was significantly decreased. The NAFLD activity score (NAS) score correlated with BA levels and reversely with adiponectin. Adiponectin reversely correlated with CD95/Fas messenger RNA (mRNA) and hepatocellular apoptosis. The BA transporter high-affinity Na+ /taurocholate cotransporter (NTCP) and the BA synthesizing enzyme cholesterol 7 alpha-hydroxylase (CYP7A1) were significantly up-regulated in obese patients and hepatoma cells exposed to FFA. Up-regulation of NTCP and CYP7A1 indicate failure to activate small heterodimer partner (SHP) upon farnesoid X receptor (FXR) stimulation by increasing BA concentrations. In line with the NAS score, adiponectin levels were reversely correlated with BA levels. Adiponectin correlated with NTCP and affects Cyp7A1 expression both in vivo and in vitro.

CONCLUSION

BA synthesis and serum BA levels correlated with disease severity in NAFLD, while adiponectin is reversely correlated. FFA exposure prevented SHP-mediated repression of NTCP and Cyp7A1 expression, which lead to increased BA synthesis and uptake. In NASH, BA accumulation induced hepatocyte cell death and late FXR activation failed to prevent hepatocyte injury due to decreased adiponectin levels. Early treatment with FXR ligands and/or adiponectin-receptor agonists might prevent NASH.