The epidemiology of non-alcoholic fatty liver disease

Disease Progression and Pharmacological Intervention in a Nutrient-Deficient Rat Model of Nonalcoholic Steatohepatitis

BACKGROUND

There is a marked need for improved animal models of nonalcoholic steatohepatitis (NASH) to facilitate the development of more efficacious drug therapies for the disease.

METHODS

Here, we investigated the development of fibrotic NASH in male Wistar rats fed a choline-deficient L-amino acid-defined (CDAA) diet with or without cholesterol supplementation for subsequent assessment of drug treatment efficacy in NASH biopsy-confirmed rats. The metabolic profile and liver histopathology were evaluated after 4, 8, and 12 weeks of dieting. Subsequently, rats with biopsy-confirmed NASH were selected for pharmacological intervention with vehicle, elafibranor (30 mg/kg/day) or obeticholic acid (OCA, 30 mg/kg/day) for 5 weeks.

RESULTS

The CDAA diet led to marked hepatomegaly and fibrosis already after 4 weeks of feeding, with further progression of collagen deposition and fibrogenesis-associated gene expression during the 12-week feeding period. Cholesterol supplementation enhanced the stimulatory effect of CDAA on gene transcripts associated with fibrogenesis without significantly increasing collagen deposition. Pharmacological intervention with elafibranor, but not OCA, significantly reduced steatohepatitis scores, and fibrosis-associated gene expression, however, was unable to prevent progression in fibrosis scores.

CONCLUSION

CDAA-fed rats develop early-onset progressive NASH, which offers the opportunity to probe anti-NASH compounds with potential disease-modifying properties.

Adipose may actively delay progression of NAFLD by releasing tumor-suppressing, anti-fibrotic miR-122 into circulation

Nonalcoholic fatty liver disease (NAFLD) is the most common liver pathology. Here we propose tissue-cooperative, homeostatic model of NAFLD. During early stages of NAFLD the intrahepatic production of miR-122 falls, while the secretion of miRNA-containing exosomes by adipose increases. Bloodstream carries exosome to the liver, where their miRNA cargo is released to regulate their intrahepatic targets. When the deterioration of adipose catches up with the failing hepatic parenchyma, the external supply of liver-supporting miRNAs gradually tapers off, leading to the fibrotic decompensation of the liver and an increase in hepatic carcinogenesis. This model may explain paradoxical observations of the disease-associated decrease in intrahepatic production of certain miRNAs with an increase in their levels in serum. Infusions of miR-122 and, possibly, some other miRNAs may be efficient for preventing NAFLD-associated hepatocellular carcinoma. The best candidates for exosome-wrapped miRNA producer are adipose tissue-derived mesenchymal stem cells (MSCs), known for their capacity to shed large amounts of exosomes into the media. Notably, MSC-derived exosomes with no specific loading are already tested in patients with liver fibrosis. Carrier exosomes may be co-manufactured along with their cargo. Exosome-delivered miRNA cocktails may augment functioning of human organs suffering from a variety of chronic diseases.

Perioperative and prognostic implication of albumin-bilirubin-TNM score in Child-Pugh class A hepatocellular carcinoma

BACKGROUND AND AIM

A reliable classification for predicting postoperative prognosis and perioperative risk of hepatocellular carcinoma (HCC) patients is required to make a precise decision for HCC treatment. In the present study, we assessed the perioperative and prognostic importance of indocyanine green (ICG) testing, tumor-node-metastasis (TNM) stage, albumin-bilirubin (ALBI) grade, and ALBI-TNM (ALBI-T) score using consecutive resected HCC cases.

METHODS

Between 1998 and 2011, 273 consecutive patients who underwent primary and curative hepatectomy for HCC were identified. Among these 273 cases, 235 Child-Pugh class A patients were enrolled in the present study.

RESULTS

Correlation analysis showed that the value of linear predictor for ALBI grade was significantly correlated with ICG 15-minute retention rates (r = 0.51, P < 0.0001). Survival analysis for both recurrence-free survival (RFS) and overall survival (OS) showed there were significant differences between the two groups stratified by stage or ALBI-T score (stage, RFS: P = 0.01, OS: P = 0.003; ALBI-T, RFS: P < 0.0001, OS: P < 0.0001). In addition, Cox proportional hazard model identified ALBI-T score was a significant predictor for both RFS and OS (RFS, P = 0.001; OS, P = 0.004). Furthermore, ALBI-T score could predict perioperative risk in hepatectomy such as longer operation time and excessive intraoperative blood loss.

CONCLUSIONS

This study showed a robust association of ALBI-T score with postoperative HCC patient survival and perioperative risk in hepatectomy. ALBI-T score can be used as a simple and powerful tool for assessing HCC patients with further study.

Attenuation by Tetrahydrocurcumin of Adiposity and Hepatic Steatosis in Mice with High-Fat-Diet-Induced Obesity

Diet-induced obesity is strongly associated with nonalcoholic fatty-liver disease (NAFLD) and insulin resistance. We aimed to investigate the in vivo therapeutic value of tetrahydrocurcumin (THC) intervention in high-fat-diet (HFD)-induced obesity and hepatic steatosis. C57BL/6 mice were fed an HFD for 10 weeks, and then they received 20 or 100 mg/kg THC along with the HFD for another 10 weeks. Mice fed an HFD for 20 weeks experienced obesity, hepatic steatosis, hyperlipidemia, and insulin resistance. Tetrahydrocurcumin (THC) intervention for 10 weeks significantly reduced adiposity (epididymal-fat weights of 6.6 ± 0.4 g for the HFD-only group and 5.3 ± 0.8 and 5.6 ± 0.7 g for the HFD with 20 mg/kg THC and HFD with 100 mg/kg THC groups, respectively; p < 0.05) via downregulation of adipogenic factors. Inflammatory macrophage infiltration and polarization were decreased by THC in mouse epididymal adipose tissues. In the liver, THC markedly alleviated steatosis by approximately 28-37% ( p < 0.05) via the downregulation of lipogenesis, the activation of AMP-activated protein kinase (AMPK), and the increase of fatty acid oxidation. Elevated blood glucose and insulin resistance were also improved by THC, which might be caused by regulation of the hepatic insulin signaling cascade, gene transcription involved in glucose metabolism, and reduced macrophage infiltration in the liver and adipose tissue. Our results demonstrated the beneficial effects of THC-mediated intervention against obesity and NAFLD as well as other metabolic syndromes, revealing a novel therapeutic use of THC in obese populations.

Night shift work and abnormal liver function: is non-alcohol fatty liver a necessary mediator?

OBJECTIVES

Accumulated evidence implies that night shift work may trigger liver dysfunction. Non-alcoholic fatty liver (NAFL) is suggested to be a necessary mediator in this process. This study aimed to examine the relationship between night shift work and elevated level of alanine transaminase (e-ALT) of workers and investigate the potential mediation effect of NAFL.

METHODS

This study included all male workers from the baseline survey of a cohort of night shift workers. Information on demographics, lifestyle and lifetime working schedule was collected by face-to-face interview. Liver sonography was used to identify NAFL cases. Serum ALT level was detected by an automatic biochemical analyser. e-ALT was defined as ALT >40 U/L. Logistic regression models were used to evaluate ORs, and mediation analysis was employed to examine the mediation effect.

RESULTS

Among 4740 male workers, 39.5% were night shift workers. Night shift workers had an increased risk of e-ALT (OR, 1.19, 95% CI 1.00 to 1.42). With the increase in night shift years, the OR of e-ALT increased from 1.03 (95% CI 0.77 to 1.36) to 1.60 (95% CI 1.08 to 2.39) among workers without NAFL. A similar trend was not found among workers with NAFL. In addition, no significant mediation effect of NAFL in the association between night shift work and e-ALT was found.

CONCLUSIONS

Night shift work is positively associated with abnormal liver function, in particular among workers without NAFL. Shift work involving circadian disruption is likely to exert a direct effect on liver dysfunction rather than rely on the mediation effect of NAFL.

Mechanisms involved in the death of steatotic WIF-B9 hepatocytes co-exposed to benzo[a]pyrene and ethanol: a possible key role for xenobiotic metabolism and nitric oxide

We previously demonstrated that co-exposing pre-steatotic hepatocytes to benzo[a]pyrene (B[a]P), a carcinogenic environmental pollutant, and ethanol, favored cell death. Here, the intracellular mechanisms underlying this toxicity were studied. Steatotic WIF-B9 hepatocytes, obtained by a 48h-supplementation with fatty acids, were then exposed to B[a]P/ethanol (10 nM/5 mM, respectively) for 5 days. Nitric oxide (NO) was demonstrated to be a pivotal player in the cell death caused by the co-exposure in steatotic hepatocytes. Indeed, by scavenging NO, CPTIO treatment of co-exposed steatotic cells prevented not only the increase in DNA damage and cell death, but also the decrease in the activity of CYP1, major cytochrome P450s of B[a]P metabolism. This would then lead to an elevation of B[a]P levels, thus possibly suggesting a long-lasting stimulation of the transcription factor AhR. Besides, as NO can react with superoxide anion to produce peroxynitrite, a highly oxidative compound, the use of FeTPPS to inhibit its formation indicated its participation in DNA damage and cell death, further highlighting the important role of NO. Finally, a possible key role for AhR was pointed out by using its antagonist, CH-223191. Indeed it prevented the elevation of ADH activity, known to participate to the ethanol production of ROS, notably superoxide anion. The transcription factor, NFκB, known to be activated by ROS, was shown to be involved in the increase in iNOS expression. Altogether, these data strongly suggested cooperative mechanistic interactions between B[a]P via AhR and ethanol via ROS production, to favor cell death in the context of prior steatosis.

The effects of metabolic status on non-alcoholic fatty liver disease-related outcomes, beyond the presence of obesity

BACKGROUND

Metabolically healthy obesity (MHO) shows a reduced risk compared with obese patients with adverse metabolic conditions. Lean people suffering some metabolic derangements also have non-alcoholic fatty liver disease (NAFLD)-related outcomes compared with non-obese subjects with a few metabolic risks.

AIM

To define the impact of the metabolic status on the NAFLD-related outcomes, beyond the presence of obesity.

METHODS

We designed a multicentre cross-sectional study, including 1058 biopsy-proven NAFLD patients. Metabolically healthy status was strictly defined by the lack of metabolic risk factors (diabetes mellitus, low HDL, hypertriglyceridemia, arterial hypertension). Non-alcoholic steatohepatitis (NASH) and significant fibrosis (F2-F4) were identified by liver biopsy. Chronic kidney disease epidemiology collaboration equation was calculated for kidney function and the atherogenic index of plasma (AIP) for cardiovascular risk.

RESULTS

Metabolically healthy (OR 1.88; P = 0.050) and unhealthy obesity (OR 3.47: P < 0.0001), and unhealthy non-obesity (OR 3.70; P < 0.0001) were independently associated with NASH together with homeostatic model assessment (HOMA), ALT, and platelets. Significant fibrosis was more frequently observed in the presence of adverse metabolic conditions in obese (OR 3.89; P = 0.003) and non-obese patients (OR 3.92; P = 0.002), and independently associated with platelets, albumin, ALT, HOMA, and age. The number of metabolic factors determined the risk of NASH and significant fibrosis. Glomerular filtration rate was lower in unhealthy (91.7 ± 18) than healthy metabolism (95.6 ± 17) (P = 0.007). AIP was higher in adverse metabolic conditions (P = 0.0001). Metabolically unhealthy non-obesity showed higher liver damage (NASH 55.8% vs 42.4%; P < 0.05; significant fibrosis 31.7% vs 11.4%; P < 0.0001) and cardiovascular risk (P < 0.0001) than healthy obesity.

CONCLUSIONS

Metabolic unhealthy status showed a greater impact on NASH, significant fibrosis, kidney dysfunction, and atherogenic profile than obesity. However, metabolically healthy obesity was not a full healthy condition. We should focus our messages especially on patients with adverse metabolic conditions.

Evaluation of hepatic function using dynamic contrast-enhanced magnetic resonance imaging in melanocortin 4 receptor-deficient mice as a model of nonalcoholic steatohepatitis

INTRODUCTION

Melanocortin 4 receptor-deficient (MC4R-KO) mice fed a high-fat diet (HFD) develop liver pathology similar to human nonalcoholic steatohepatitis (NASH). However, although liver histology and blood biochemistry have been reported, hepatic function has not been evaluated. In the present study, we evaluated hepatic function in MC4R-KO mice fed an HFD using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with gadolinium‑ethoxybenzyl‑diethylenetriamine pentaacetic acid (Gd-EOB-DTPA).

MATERIALS AND METHODS

Wild type (WT) mice and MC4R-KO mice were fed a standard diet (SD) or an HFD for 20 weeks. The hepatic signal intensity was obtained from DCE-MRI images, and relative enhancement (RE), the time to maximum RE (T_max), and the half-life of RE elimination (T_1/2) were calculated. Histopathological analysis was then performed.

RESULTS

Histological analysis with nonalcoholic fatty liver disease activity score (NAS) revealed that MC4R-KO mice fed an HFD achieved the NAS of 5. There was moderate fibrosis in MC4R-KO mice fed an HFD. DCE-MRI with Gd-EOB-DTPA showed that T_max and T_1/2 were significantly longer in MC4R-KO mice fed an HFD compared with wild type (WT) mice (T_max, WT, 3.9 ± 0.4 min; MC4R-KO, 7.4 ± 1.5 min; T_1/2, WT, 23.7 ± 1.9 min; MC4R-KO, 62.5 ± 18.5 min). T_max and T_1/2 were significantly correlated with histopathologic score (steatosis vs. Tmax, rho = 0.48, P = 0.04; steatosis vs. T_1/2, rho = 0.50, P = 0.03; inflammation vs. Tmax, rho = 0.55, P = 0.02; inflammation vs. T_1/2, rho = 0.61, P < 0.01; ballooning vs. T_1/2, rho = 0.51, P = 0.03;fibrosis vs T_max, rho = 0.72, P < 0.01; fibrosis vs T_1/2, rho = 0.75, P < 0.01).

CONCLUSIONS

MC4R-KO mice fed an HFD developed obesity and NASH. The liver kinetics of Gd-EOB-DTPA were significantly different in MC4R-KO mice fed an HFD from WT mice, and correlated with the histopathologic score. These results suggest that MC4R-KO mice fed an HFD mimic the hepatic pathology and liver function of human NASH, and therefore might be useful for the study of hepatic dysfunction during the fibrotic stage of NASH.

High dietary intake of palm oils compromises glucose tolerance whereas high dietary intake of olive oil compromises liver lipid metabolism and integrity

PURPOSE

Palm (PO) and olive oils (OO) are the two most consumed and/or used oils in the world for food elaboration. These oils should not be confused with the solid palm stearin which is widely used in pastry making. Large number of studies was reported dealing with adverse/beneficial cardiovascular effects of PO and OO, whereas few studies were conducted to compare their potential effects on hepatic steatosis and liver lipid metabolism. The aim of this study was to compare the metabolic effects of high intake of POs (both crude and refined) and virgin OO on surrogate parameters of glucose tolerance, hepatic lipid metabolism and liver integrity.

METHODS

Thirty-two young male Wistar rats were divided into four equal groups and fed either control diet (11% energy from fat) or three high-fat diets rich in crude or refined POs or in OO (56% energy from fat), during 12 weeks. Systemic blood and liver biochemical parameters linked to glucose and lipid metabolism as well as hepatic steatosis and liver fatty acid composition were explored. The inflammation and oxidative stress status as well as the expression of several genes/proteins were also analyzed.

RESULTS

The major effects of POs intake concerned glucose metabolism and liver fatty acid composition, whereas the major effects of OO intake concerned hepatic TG accumulation, inflammation, and cytolysis.

CONCLUSIONS

In conclusion, high dietary intake of PO compromises glucose tolerance whereas high dietary intake of OO compromises hepatic lipid composition and liver integrity. However, adverse hepatic effects of OO observed in this study may not be transposed to human since, (a) the rodent model could lead to different effects than those observed in humans and (b) the average normal OO amounts ingested in the population are lower than those corresponding to a high-fat diet. So, further studies are needed to determine a maximum non-invasive dietary intake of OO.

Histopathological and biochemical changes in the development of nonalcoholic fatty liver disease induced by high-sucrose diet at different times

The high intake of sweetened drinks is associated with obesity and insulin resistance. These pathologies are directly related to the development of nonalcoholic fatty liver disease (NAFLD), considered a condition of metabolic syndrome (MS). Due to their increasing worldwide prevalence, experimental animal models have been developed to gain a better understanding of its physiopathology; notwithstanding, few studies have evaluated its progression in association with MS and ingestion of sweetened drinks. Therefore, the aim of this study was to understand the pathophysiologic characteristics of NAFLD related to sucrose concentration and time of ingestion in rats. Wistar rats were divided into 2 groups with free access to either tap water or 30% sucrose, and euthanized at 12, 16, or 20 weeks; and 2 additional groups were given free access to either 40% or 50% sucrose and were euthanized at 20 weeks. Biochemical parameters and levels of serum cytokines were measured, and histology was performed. Ingestion of 30% sucrose induced liver steatosis until 16 weeks (grade 2) and 20 weeks (grade 3). Meanwhile, during 20 weeks, 40% sucrose induced grade 5 of nonalcoholic steatohepatitis (NASH) and 50% sucrose induced grade 6 of NASH and fibrosis. This study demonstrated that increasing time of induction and concentration of sucrose ingestion resulted in a higher grade of NAFLD.

Predictive factors associated with liver fibrosis and steatosis by transient elastography in patients with HIV mono-infection under long-term combined antiretroviral therapy

INTRODUCTION

Non-alcoholic fatty liver disease is characterized by the presence of hepatic steatosis and can be associated with fibrosis progression, development of cirrhosis and liver-related complications. Data on the prevalence of liver fibrosis and steatosis in HIV patients remain contradictory in resource-limited settings. We aimed to describe the prevalence and factors associated with liver fibrosis and steatosis in patients with HIV mono-infection under long-term antiretroviral therapy (ART) in Rio de Janeiro, Brazil.

METHODS

Clinical assessment, fasting blood collection and liver stiffness measurement (LSM)/controlled attenuation parameter (CAP) by transient elastography were performed on the same day for this cross-sectional study (PROSPEC-HIV study; NCT02542020). Patients with viral hepatitis co-infection, ART-naïve or missing data were excluded. Liver fibrosis and steatosis were defined by LSM ≥ 8.0 kPa and CAP ≥ 248 dB/m respectively. HIV history, cumulative and current ART regimens were evaluated. Multivariate logistic regression models adjusted for age and gender were performed.

RESULTS

In total, 395 patients (60% female; median age of 45 (IQR, 35 to 52) years, body mass index = 25.7 (23.2 to 29.4) kg/m2 , alanine aminotransferase = 30 (23 to 42) IU/L, duration of ART for 7 (4 to 14) years) were included. LSM and CAP were reliable in 93% (n = 367) and 87% (n = 344) respectively. The prevalence of fibrosis and steatosis were 9% (95% confidence interval (CI), 7 to 13) and 35% (95% CI, 30 to 40) respectively. The following factors were associated with fibrosis (odds ratio (OR) (95% CI)): older age (per 10 years; 1.80 (1.27 to 2.55); p = 0.001) and CD4+ count <200 cells/mm3 (7.80 (2.09 to 29.09), p = 0.002). Type 2 diabetes had a trend towards the presence of liver fibrosis (2.67 (0.96 to 7.46), p = 0.061). Central obesity (10.74 (4.40 to 26.20), p < 0.001), type 2 diabetes (9.74 (3.15 to 30.10), p < 0.001), dyslipidaemia (2.61 (1.35 to 5.05), p = 0.003) and metabolic syndrome (4.28 (2.45 to 7.46), p < 0.001) were associated with steatosis. A dominant backbone ART regimen of zidovudine (AZT), d4T, ddI or ddC was associated with steatosis (1.90 (1.07 to 3.38), p = 0.028) independently of metabolic features.

CONCLUSION

Integrated strategies for preventing non-communicable diseases in people with HIV mono-infection are necessary to decrease the burden of liver diseases. Clinical Trial Number: NCT02542020.

How Much Ischemia Can the Severely Steatotic Rat Liver Tolerate?

AIM

Steatotic liver is more susceptible to ischemia-reperfusion injury than is lean liver. Our aim was to investigate the ability of the severely steatotic rat liver to sustain ischemia.

MATERIALS AND METHODS

One hundred male Wistar rats aged 12-14 weeks were included. Fifty rats were given regular diet, while the rest were given a choline-free diet for 12-14 weeks to develop severe liver steatosis. Each group was divided into the following five subgroups: Sham-operated, and 5, 10, 15 and 20 minutes of continuous vascular inflow occlusion. Serum glutamic-oxaloacetic transaminase and serum glutamic-pyruvic transaminase levels were measured at 24 hours postoperatively and the animals were surveilled for 30 days.

RESULTS

Serum transaminase levels increased as the duration of ischemia increased in lean livers (p<0.0001), without a significant impact on animal survival. Similarly, serum transaminase levels increased as the duration of ischemia increased in severely steatotic livers (p<0.0001), reaching a plateau after 15 minutes of liver ischemia. Survival was significantly affected after the same cut-off point in rats with steatotic liver (p<0.0001). Serum transaminase levels were greater in severely rats with steatotic liver than in rats with lean liver, when they were adjusted for the duration of liver ischemia. Moreover, survival was reduced when serum transaminase levels surpassed the threshold of 2,000 IU/l (p<0.0001).

CONCLUSION

Severely steatotic rat liver can safely tolerate up to 10 minutes of continuous ischemia, with survival being affected after 15 minutes or more. On the other hand, lean rat liver can safely tolerate even 20 minutes of continuous ischemia.

Phenotypical heterogeneity in responder and nonresponder male ApoE*3Leiden.CETP mice

The metabolic syndrome (MetS) is a major health issue worldwide and is associated with obesity, insulin resistance, and hypercholesterolemia. Several animal models were used to describe the MetS; however, many of them do not mimic well the MetS pathophysiology in humans. The ApoE*3Leiden.CETP mouse model overcomes part of this limitation, since they have a humanised lipoprotein metabolism and a heterogeneous response to MetS, similar to humans. The reported heterogeneity among them and their common classification refer to responder (R) and nonresponder (NR) mice; R mice show increased body weight, cholesterol, and triglycerides levels, whereas NR mice do not show this expected phenotype when fed a Western type diet. To define better the differences between R and NR mice, we focused on feeding behavior, body weight gain, glucose tolerance, and lipid parameters, and on an extensive pathological examination along with liver histology analysis. Our data confirmed that R mice resemble the pathological features of the human MetS: obesity, dysplipidemia, and glucose intolerance. NR mice do not develop the full dysmetabolic phenotype because of a severe inflammatory hepatic condition, which may heavily affect liver function. We conclude that R and NR mice are metabolically different and that NR mice have indications of severely impaired liver function. Hence, it is critical to identify and separate the respective mice to decrease data heterogeneity. Clinical chemistry and histological analysis should be used to confirm retrospectively the animals' classification. Moreover, we point out that NR mice may not be an appropriate control for studies involving ApoE*3Leiden.CETP R mice. NEW & NOTEWORTHY When compared with some other animal models, ApoE*3Leiden.CETP mice are better models to describe the metabolic syndrome. However, there is phenotypic heterogeneity between "responder" and "nonresponder" mice, the latter showing some evidence of hepatic pathology. A full phenotypic characterization and eventually postmortem analysis of the liver are warranted.

The correlation between controlled attenuation parameter and metabolic syndrome and its components in middle-aged and elderly nonalcoholic fatty liver disease patients

This study aims to investigate the correlation between controlled attenuation parameter (CAP) and metabolic syndrome (MetS) and its components in middle-aged and elderly nonalcoholic fatty liver disease (NAFLD) patients.Middle-aged and elderly patients with NAFLD, who visited our hospital from June 2016 to May 2017, were enrolled as study subjects, whereas middle-aged and elderly patients without liver disease were enrolled as controls in the same period. The prevalence of MetS, MetS components, and the different numbers of MetS components were compared among patients with different CAP values.As the CAP value increased, the prevalence of MetS, MetS components, and the different numbers of MetS components significantly increased. The CAP value was positively correlated with the prevalence of MetS, obesity, hypertriglyceridemia, hypertension, hyperglycemia, hyperuricemia, and the number of MetS components, and was negatively correlated with the prevalence of hypo-high-density-lipoprotein cholesterolemia.CAP values are closely correlated to MetS and its components in middle-aged and elder NAFLD patients. CAP may be an indicator of risk of MetS and the severity of metabolic disorders in middle-aged and elderly NAFLD patients.

Branched chain amino acid transaminase 1 (BCAT1) is overexpressed and hypomethylated in patients with non-alcoholic fatty liver disease who experience adverse clinical events: A pilot study

Background and objectives

Although the burden of non-alcoholic fatty liver disease (NAFLD) continues to increase worldwide, genetic factors predicting progression to cirrhosis and decompensation in NAFLD remain poorly understood. We sought to determine whether gene expression profiling was associated with clinical decompensation and death in patients with NAFLD, and to assess whether altered DNA methylation contributes to these changes in gene expression.

Methods

We performed a retrospective analysis of 86 patients in the Duke NAFLD Clinical Database and Biorepository with biopsy-proven NAFLD whose liver tissue was previously evaluated for gene expression and DNA methylation using array based technologies. We assessed the prospective development of liver and cardiovascular disease related outcomes, including hepatic decompensation as identified by the development of ascites, hepatic encephalopathy, hepatocellular carcinoma, or variceal bleeding as well as stroke and myocardial infarction via medical chart review.

Results

Of the 86 patients, 47 had F0-F1 fibrosis and 39 had F3-F4 fibrosis at index liver biopsy. Gene expression probe sets (n = 54,675) were analyzed; 42 genes showed significant differential expression (p<0.05) and a two-fold change in expression between patients with and without any outcome. Two expression probes of the branched chain amino-acid transaminase 1 (BCAT1) gene were upregulated (p = 0.02; fold change 2.1 and 2.2 respectively) in patients with a clinical outcome. Methylation of three of the 34 BCAT1 CpG methylation probes were significantly inversely correlated with BCAT1 expression specific to the probes predictive of clinical deterioration.

Conclusion

We found differential gene expression, correlated to changes in DNA methylation, at multiple BCAT1 loci in patients with cardiovascular outcomes and/or hepatic decompensation. BCAT1 catalyzes the transformation of alpha-ketoglutarate to glutamate and has been linked to the presence and severity of NAFLD, possibly through derangements in the balance between glutamate and alpha-ketoglutarate. Given the potential for BCAT1 to identify patients at risk for poor outcomes, and the potential therapeutic implications, these results should be validated in larger prospective studies.

A nonalcoholic fatty liver disease model in human induced pluripotent stem cell-derived hepatocytes, created by endoplasmic reticulum stress-induced steatosis

Hepatic steatosis, a reversible state of metabolic dysregulation, can promote the onset of nonalcoholic steatohepatitis (NASH), and its transition is thought to be critical in disease evolution. The association between endoplasmic reticulum (ER) stress response and hepatocyte metabolism disorders prompted us to characterize ER stress-induced hepatic metabolic dysfunction in human induced pluripotent stem cell-derived hepatocytes (hiPSC-Hep), to explore regulatory pathways and validate a phenotypic in vitro model for progression of liver steatosis. We treated hiPSC-Hep with a ratio of unsaturated and saturated fatty acids in the presence of an inducer of ER stress to synergistically promote triglyceride accumulation and dysregulate lipid metabolism. We monitored lipid accumulation by high-content imaging and measured gene regulation by RNA sequencing and reverse transcription quantitative PCR analyses. Our results show that ER stress potentiated intracellular lipid accumulation by 5-fold in hiPSC-Hep in the absence of apoptosis. Transcriptome pathway analysis identified ER stress pathways as the most significantly dysregulated of all pathways affected. Obeticholic acid dose dependently inhibited lipid accumulation and modulated gene expression downstream of the farnesoid X receptor. We were able to identify modulation of hepatic markers and gene pathways known to be involved in steatosis and nonalcoholic fatty liver disease (NAFLD), in support of a hiPSC-Hep disease model that is relevant to clinical data for human NASH. Our results show that the model can serve as a translational discovery platform for the understanding of molecular pathways involved in NAFLD, and can facilitate the identification of novel therapeutic molecules based on high-throughput screening strategies.

Summary: Our study demonstrates expanded use of human induced pluripotent stem cell-derived hepatocytes for molecular studies and drug screening, to evaluate new therapeutics with an antisteatotic mechanism of action for nonalcoholic fatty liver disease.

Sex-specific differences in hepatic steatosis in obese spontaneously hypertensive (SHROB) rats

Background

Patients with metabolic syndrome, who are characterized by co-existence of insulin resistance, hypertension, hyperlipidemia, and obesity, are also prone to develop non-alcoholic fatty liver disease (NAFLD). Although the prevalence and severity of NAFLD is significantly greater in men than women, the mechanisms by which gender modulates the pathogenesis of hepatic steatosis are poorly defined. The obese spontaneously hypertensive (SHROB) rats represent an attractive model of metabolic syndrome without overt type 2 diabetes. Although pathological manifestation caused by the absence of a functional leptin receptor has been extensively studied in SHROB rats, it is unknown whether these animals elicited sex-specific differences in the development of hepatic steatosis.

Methods

We compared hepatic pathology in male and female SHROB rats. Additionally, we examined key biochemical and molecular parameters of signaling pathways linked with hyperinsulinemia and hyperlipidemia. Finally, using methods of quantitative polymerase chain reaction (qPCR) and western blot analysis, we quantified expression of 45 genes related to lipid biosynthesis and metabolism in the livers of male and female SHROB rats.

Results

We show that all SHROB rats developed hepatic steatosis that was accompanied by enhanced expression of SREBP1, SREBP2, ACC1, and FASN proteins. The livers of male rats also elicited higher induction of Pparg, Ppara, Slc2a4, Atox1, Skp1, Angptl3, and Pnpla3 mRNAs. In contrast, the livers of female SHROB rats elicited constitutively higher levels of phosphorylated JNK and AMPK and enhanced expression of Cd36.

Conclusion

Based on these data, we conclude that the severity of hepatic steatosis in male and female SHROB rats was mainly driven by increased de novo lipogenesis. Moreover, male and female SHROB rats also elicited differential severity of hepatic steatosis that was coupled with sex-specific differences in fatty acid transport and esterification.

Electronic supplementary material

The online version of this article (10.1186/s13293-018-0202-x) contains supplementary material, which is available to authorized users.

Clinicopathologic characteristics andoutcomes of hepatocellular carcinoma associated with chronic hepatitis B versus hepatitis C infection

BACKGROUND

Hepatocellular carcinoma (HCC) is a primary liver malignancy and one of the most common cancers worldwide. Few studies in Saudi Arabia have compared the clinicopathologic characteristics of HCC caused by hepatitis B virus (HBV) versus hepatitis C virus (HCV) and their effect on patient survival and prognosis.

OBJECTIVES

Identify differences in clinicopathological characteristics and outcomes of hepatocellular carcinoma (HCC) caused by HBV versus HCV.

DESIGN

A retrospective medical records review.

SETTING

Tertiary medical center in Riyadh.

PATIENTS AND METHODS

We included all new cases of HCC with underlying HBV and HCV infection diagnosed between January 2013 and September 2017 that met inclusion criteria.

MAIN OUTCOME MEASURES

Clinical, biochemical, pathological and radiological characteristics, and survival differences were compared between HCC that developed in HBV- and HCV-infected patients.

SAMPLE SIZE

Of 253 patients evaluated, 172 patients were included in the study.

RESULTS

Of the 172 patients, 110 (64%) had HCV-associated HCC and 62 (36%) had HBV-associated HCC. More patients with HBV infection were males (P=.003) and were younger (P=.015) than HCV patients. HCV-infected patients who developed HCC had more advanced cirrhosis (P=.048). The prevalence of comorbidities and pre-existing cir.rhosis was similar in both groups. Seven patients (6.8%) with underlying HCV developed HCC in the absence of cirrhosis. Patients with HBV-associated HCC were less likely to meet Milan criteria at initial diagnosis than those with HCV-associated HCC (33.9% vs. 52.7%, respectively, P=.017). HBV-associated HCC occurred at a more advanced Barcelona Clinic Liver Cancer stage. The overall median survival and treatment outcome for each modality was comparable.

CONCLUSIONS

HBV- and HCV-associated HCC have distinct clinical and pathological characteristics, necessitating different screening policies to optimize HCC surveillance and management. However, viral etiology did not affect the treatment outcome and long-term survival.

LIMITATIONS

Conducted in a single-center, retrospective and lacks information about the use of antiviral treatment.

CONFLICT OF INTEREST

None.

Molecular Pathogenesis of Nonalcoholic Steatohepatitis- (NASH-) Related Hepatocellular Carcinoma

The proportion of obese or diabetic population has been anticipated to increase in the upcoming decades, which rises the prevalence of nonalcoholic fatty liver disease (NAFLD) and its progression to nonalcoholic steatohepatitis (NASH). Recent evidence indicates that NASH is the main cause of chronic liver diseases and it is an important risk factor for development of hepatocellular carcinoma (HCC). Although the literature addressing NASH-HCC is growing rapidly, limited data is available about the etiology of NASH-related HCC. Experimental studies on the molecular mechanism of HCC development in NASH reveal that the carcinogenesis is relevant to complex changes in signaling pathways that mediate cell proliferation and energy metabolism. Genetic or epigenetic modifications and alterations in metabolic, immunologic, and endocrine pathways have been shown to be closely related to inflammation, liver injury, and fibrosis in NASH along with its subsequent progression to HCC. In this review, we provide an overview on the current knowledge of NASH-related HCC development and emphasize molecular signaling pathways regarding their mechanism of action in NASH-derived HCC.

The association between missing teeth and non-alcoholic fatty liver disease in adults

AIMS

Long-term oral chronic inflammatory process is closely related to systemic inflammation, which is a main mechanism involved in non-alcoholic fatty liver disease (NAFLD). Tooth loss could reflect the accumulation of oral local inflammation, implying that number of missing teeth may associate with NAFLD. This study evaluated the association between missing teeth and presence of NAFLD in a general population.

MATERIALS AND METHODS

A cross-sectional study of 24,470 adults was carried out from the Tianjin Chronic Low-grade Systemic Inflammation and Health Cohort Study. The self-reported number of missing teeth (excluding third molars) was recorded and classified into four categories: 0, 1-2, 3-5, and ≥6. The NAFLD was diagnosed by the liver ultrasonography. Associations were analysed by adjusted multivariable logistic regression.

RESULTS

The multivariable-adjusted odds ratios (95% confidence interval) of NAFLD across the categories of missing teeth were as follows: in males, 1.00 (reference), 1.04 (0.93-1.16), 1.06 (0.90-1.24), and 1.40 (1.09-1.81) (p for trend = 0.04); in females, 1.00 (reference), 0.98 (0.83-1.15), 1.11 (0.90-1.37), and 1.07 (0.77-1.48) (p for trend = 0.45).

CONCLUSIONS

The number of missing teeth was associated with a higher presence of NAFLD in males but not females.

Possible Involvement of Mitochondrial Dysfunction and Oxidative Stress in a Cellular Model of NAFLD Progression Induced by Benzo[a]pyrene/Ethanol CoExposure

Exposure to xenobiotics could favor the transition of nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis in obese patients. Recently, we showed in different models of NAFL that benzo[a]pyrene (B[a]P) and ethanol coexposure induced a steatohepatitis-like state. One model was HepaRG cells incubated with stearate and oleate for 2 weeks. In the present study, we wished to determine in this model whether mitochondrial dysfunction and reactive oxygen species (ROS) overproduction could be involved in the occurrence of this steatohepatitis-like state. CRISPR/Cas9-modified cells were also used to specify the role of aryl hydrocarbon receptor (AhR), which is potently activated by B[a]P. Thus, nonsteatotic and steatotic HepaRG cells were treated with B[a]P, ethanol, or both molecules for 2 weeks. B[a]P/ethanol coexposure reduced mitochondrial respiratory chain activity, mitochondrial respiration, and mitochondrial DNA levels and induced ROS overproduction in steatotic HepaRG cells. These deleterious effects were less marked or absent in steatotic cells treated with B[a]P alone or ethanol alone and in nonsteatotic cells treated with B[a]P/ethanol. Our study also disclosed that B[a]P/ethanol-induced impairment of mitochondrial respiration was dependent on AhR activation. Hence, mitochondrial dysfunction and ROS generation could explain the occurrence of a steatohepatitis-like state in steatotic HepaRG cells exposed to B[a]P and ethanol.

Apoptosis and non-alcoholic fatty liver diseases

The number of patients with nonalcoholic fatty liver diseases (NAFLD) including nonalcoholic steatohepatitis (NASH), has been increasing. NASH causes cirrhosis and hepatocellular carcinoma (HCC) and is one of the most serious health problems in the world. The mechanism through which NASH progresses is still largely unknown. Activation of caspases, Bcl-2 family proteins, and c-Jun N-terminal kinase-induced hepatocyte apoptosis plays a role in the activation of NAFLD/NASH. Apoptotic hepatocytes stimulate immune cells and hepatic stellate cells toward the progression of fibrosis in the liver through the production of inflammasomes and cytokines. Abnormalities in glucose and lipid metabolism as well as microbiota accelerate these processes. The production of reactive oxygen species, oxidative stress, and endoplasmic reticulum stress is also involved. Cell death, including apoptosis, seems very important in the progression of NAFLD and NASH. Recently, inhibitors of apoptosis have been developed as drugs for the treatment of NASH and may prevent cirrhosis and HCC. Increased hepatocyte apoptosis may distinguish NASH from NAFLD, and the improvement of apoptosis could play a role in controlling the development of NASH. In this review, the association between apoptosis and NAFLD/NASH are discussed. This review could provide their knowledge, which plays a role in seeing the patients with NAFLD/NASH in daily clinical practice.

Development and validation of diagnostic triage criteria for liver disease from a minimum data set enabling the 'intelligent LFT' pathway for the automated assessment of deranged liver enzymes

BACKGROUND

Liver function tests (LFTs) are commonly abnormal; most patients with 'incidental' abnormal LFTs are not investigated appropriately and for those who are, current care pathways are geared to find an explanation for the abnormality by a lengthy process of investigation and exclusion, with costs to the patient and to the health service.

OBJECTIVE

To validate an intelligent automatable analysis tool (iLFT) for abnormal liver enzymes, which diagnoses common liver conditions, provides fibrosis stage and recommends management.

DESIGN

A retrospective case note review from three tertiary referral liver centres, with application of the iLFT algorithm and comparison with the clinician's final opinion as gold standard.

RESULTS

The iLFT algorithm in 91.3% of cases would have correctly recommended referral or management in primary care. In the majority of the rest of the cases, iLFT failed safe and recommended referral even when the final clinical diagnosis could have been managed in primary care. Diagnostic accuracy was achieved in 82.4% of cases, consistent with the fail-safe design of the algorithm. Two cases would have remained in primary care as per the algorithm outcome, however on clinical review had features of advanced fibrosis.

CONCLUSION

iLFT analysis of abnormal liver enzymes offers a safe and robust method of risk stratifying patients to the most appropriate care pathway as well as providing reliable diagnostic information based on a single blood draw, without repeated contacts with health services. Offers the possibility of high quality investigation and diagnosis to all patients rather than a tiny minority.

Deficiency of fibroblast growth factor 21 (FGF21) promotes hepatocellular carcinoma (HCC) in mice on a long term obesogenic diet

OBJECTIVE

Non-alcoholic fatty liver (NAFL) associated with obesity is a major cause of liver diseases which can progress to non-alcoholic steatohepatitis, cirrhosis, and hepatocellular carcinoma (HCC). Fibroblast growth factor 21 (FGF21) plays an important role in liver metabolism and is also a potential marker for NAFL. Here we aimed to test the effect of FGF21 deficiency on liver pathology in mice consuming a conventional high fat, high sucrose (HFHS) obesogenic diet for up to 52 weeks.

METHODS

C57BL6 WT and FGF21 KO mice were fed a conventional obesogenic diet and were evaluated at 16 and 52 weeks. Evaluation included metabolic assessment, liver pathology, and transcriptomic analysis.

RESULTS

With consumption of HFHS diet, FGF21 deficient mice (FGF21 KO) develop excess fatty liver within 16 weeks. Hepatic pathology progresses and at 52 weeks FGF21 KO mice show significantly worse fibrosis and 78% of mice develop HCC; in contrast only 6% of WT mice develop HCC. Well differentiated hepatocellular carcinomas in FGF21 KO mice were characterized by expanded hepatic plates, loss of reticulin network, cytologic atypia, and positive immunostaining for glutamine synthetase. Microarray analysis reveals enrichment of several fibroblast growth factor signaling pathways in the tumors.

CONCLUSIONS

In addition to attenuating inflammation and fibrosis in mice under a number of dietary challenges, we show here that FGF21 is required to limit the progression from NAFL to HCC in response to prolonged exposure to an obesogenic diet. The induction of hepatic FGF21 in response to the high fat, high sucrose obesogenic diet may play an important role in limiting progression of liver pathology from NAFL to HCC.

Green tea as a safe alternative approach for nonalcoholic fatty liver treatment: A systematic review and meta-analysis of clinical trials

This study aimed to evaluate the efficacy of green tea supplementation on nonalcoholic fatty liver disease treatment. Electronic databases, including PubMed, Scopus, Web of Science, and Google Scholar, were systematically searched up to October 30, 2017, to identify eligible trials based on the inclusion criteria. The effect size was presented as mean difference with 95% confidence intervals (CI). The meta-analysis of data from four studies indicated significant effects of green tea supplementation in altering alanine aminotransferases (-12.81 U/L; 95% CI: -18.17 to -7.45) and aspartate aminotransferases (-10.91 U/L; 95% CI: -19.66 to -2.17) blood concentrations. Likewise, a favorable effect of green tea administration was observed on body mass index (-2.08 kg/cm² ; 95% CI: -2.81 to -1.36), triacylglycerol (-31.87 mg/dl; 95% CI: -40.62 to -23.12), total cholesterol (-27.57 mg/dl; 95% CI: -36.17 to -18.98), and low-density lipoprotein cholesterol (-14.15 mg/dl; 95% CI: -23.69 to -4.60), whereas no significant effect was detected on high-density lipoprotein cholesterol concentrations (7.41 mg/dl; 95% CI: -1.49 to 16.30) and homeostasis model assessment of insulin resistance (-4.06; 95% CI: -10.22 to 2.09). This systematic review and meta-analysis of available trials suggests that there  are potential benefits of green tea supplementation on nonalcoholic fatty liver disease.

Polymorphisms in the receptor for advanced glycation end-products (RAGE) gene and circulating RAGE levels as a susceptibility factor for non-alcoholic steatohepatitis (NASH)

Non-alcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome and major cause of chronic liver disease in developed countries. Its prevalence is increasing in parallel with the prevalence of obesity and other components of the metabolic syndrome. As the liver is central to the clearance and catabolism of circulating advanced glycosylation end-products (AGEs), AGEs and their cognate receptors—RAGE (receptor for AGEs) system might be involved in NAFLD in obese patients. To examine this, we investigated four common polymorphisms of RAGE gene: 1704G/T (rs184003), G82S (rs2070600), -374T/A (rs1800624) and −429T/C (rs1800625) in 340 obese patients with metabolic syndrome. and protein levels of AGE and RAGE. This is the first study to describe association of 4 common polymorphisms with non-alcoholic steatohepatitis (NASH) as well as to examine protein levels of RAGE and AGE. Univariate analysis showed patients carrying the rs1800624 heterozygote genotype (AT) exhibited 2.36-fold increased risk of NASH (odds ratio (OR) = 2.36; 95% confidence interval (95% CI): 1.35–4.19) after adjusting for confounders. The minor allele -374 A has been shown to suppress the expression of RAGE protein. The protein levels of esRAGE, total sRAGE and AGE protein levels did not correlate with each other in obese patients with no liver disease, indicative of RAGE signaling playing an independent role in liver injury. In obese patients with non-NASH NAFLD and NASH respectively, esRAGE protein showed strong positive correlation with total sRAGE protein. Further, haplotype analysis of the 4 SNPs, indicated that haplotype G-A-T-G was significantly associated with 2-fold increased risk for NASH (OR = 2.08; 95% CI: 1.21–3.5; P = 0.006) after adjusting for confounders. In conclusion, the presented data indicate that the G-A-T-G haplotype containing minor allele at position −374 A and major allele at position −429T, 1704G, and G82S G could be regarded as a marker for NASH.

A Controlled Fermented Samjunghwan Herbal Formula Ameliorates Non-alcoholic Hepatosteatosis in HepG2 Cells and OLETF Rats

Hepatosteatosis (HS), a clinical feature of fatty liver with the excessive intracellular accumulation of triglyceride in hepatocytes, is manifested by perturbation of the maintenance of liver lipid homeostasis. Samjunghwan (SJH) is an herbal formula used mostly in Korean traditional medicine that is effective against a number of metabolic diseases, including obesity. Herbal drugs, enriched with numerous bioactive substances, possess health-protective benefits. Meanwhile, fermented herbal products enriched with probiotics are known to improve metabolic processes. Additionally, current lines of evidence indicate that probiotics-derived metabolites, termed as postbiotics, produce the same beneficial effects as their precursors. Herein, the anti-HS effects of 5-weeks naturally fermented SJH (FSJH) was investigated with FSJH-mixed chow diet in vivo using Otsuka Long-Evans Tokushima Fatty (OLETF) and Long-Evans Tokushima Otsuka (LETO) rats as animal models of HS and controls, respectively. In parallel, the anti-HS effects of postbiotic-metabolites of three bacterial strains [Lactobacillus brevis (LBB), Lactococcus lactis (LCL) and Lactobacillus plantarum (LBP)] isolated from FSJH were also evaluated in vitro using the FFAs-induced HepG2 cells. Feeding OLETF rats with FSJH-diet effectively reduced body, liver, and visceral adipose tissue (VAT) weights, produced marked hypolipidemic effects on serum and hepatic lipid parameters, decreased serum AST and ALT levels, and upregulated the HMGCOR, SREBP, and ACC, and downregulated the AMPK and LDLR gene expressions levels. Additionally, exposure of FFAs-induced HepG2 cells to postbiotic metabolic media (PMM) of bacterial strains also produced marked hypolipidemic effects on intracellular lipid contents and significantly unregulated the HMGCOR, SREBP, and ACC, and downregulated the AMPK and LDLR genes expressions levels. Overall, our results indicate that FSJH enriched with fermented metabolites could be an effective anti-HS formulation.

Glycine N-methyltransferase deletion in mice diverts carbon flux from gluconeogenesis to pathways that utilize excess methionine cycle intermediates

Glycine N-methyltransferase (GNMT) is the most abundant liver methyltransferase regulating the availability of the biological methyl donor, S-adenosylmethionine (SAM). Moreover, GNMT has been identified to be down-regulated in hepatocellular carcinoma (HCC). Despite its role in regulating SAM levels and association of its down-regulation with liver tumorigenesis, the impact of reduced GNMT on metabolic reprogramming before the manifestation of HCC has not been investigated in detail. Herein, we used ²H/¹³C metabolic flux analysis in conscious, unrestrained mice to test the hypothesis that the absence of GNMT causes metabolic reprogramming. GNMT-null (KO) mice displayed a reduction in blood glucose that was associated with a decline in both hepatic glycogenolysis and gluconeogenesis. The reduced gluconeogenesis was due to a decrease in liver gluconeogenic precursors, citric acid cycle fluxes, and anaplerosis and cataplerosis. A concurrent elevation in both hepatic SAM and metabolites of SAM utilization pathways was observed in the KO mice. Specifically, the increase in metabolites of SAM utilization pathways indicated that hepatic polyamine synthesis and catabolism, transsulfuration, and de novo lipogenesis pathways were increased in the KO mice. Of note, these pathways utilize substrates that could otherwise be used for gluconeogenesis. Also, this metabolic reprogramming occurs before the well-documented appearance of HCC in GNMT-null mice. Together, these results indicate that GNMT deletion promotes a metabolic shift whereby nutrients are channeled away from glucose formation toward pathways that utilize the elevated SAM.

The effect of antidiabetic medications on non-alcoholic fatty liver disease (NAFLD)

Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome and is prevalent in more than 50% of patients with type II diabetes. At present, there is no approved therapy for NASH. Until now, the only proven effective interventions in improving biochemical and histological features of NASH, including fibrosis, are weight loss and physical activity even without weight loss. Because of the common epidemiological and pathophysiological features between NAFLD and T2DM, many antidiabetics drugs have been tested in patients with NAFLD over the years. Among these, pioglitazone and liraglutide seem to improve some histological features of NASH but have no clear effect on fibrosis. Metformin has been largely studied in the past years without convincing evidence of improving NAFLD. Data on other compounds such as DDP-4 and SGLT-2 inhibitors are limited. The rational and results of such studies are discussed in the present review.

The Role of Diagnosis and Treatment of Underlying Liver Disease for the Prognosis of Primary Liver Cancer

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide. Underlying chronic liver disease has been associated with an increased risk of developing HCC. This study is a review of the current literature regarding the diagnosis, prognostic significance, and role of treating underlying liver disease in patients who are at risk of primary liver cancer. Relevant peer review of the English literature between 1980 and 2017 within PubMed and the Cochrane library was conducted for scientific content on current advances in managing chronic liver diseases and the development of hepatocellular carcinoma. Hepatitis C virus, hepatitis B virus (HBV), nonalcoholic steatohepatitis, autoimmune hepatitis, hereditary hemochromatosis, Wilson disease, primary biliary cirrhosis, α 1-antitrypsin deficiency, and certain drugs lead to an increased risk of developing HCC. Patients with underlying liver disease have an increased incidence of HCC. Hepatitis C virus, HBV, and hemochromatosis can directly lead to HCC without the presence of cirrhosis, while HCC related to other underlying liver diseases occurs in patients with cirrhosis. Treating the underlying liver disease and reducing the progression to cirrhosis should lead to a decreased incidence of HCC.

Challenges in diagnosing and monitoring diabetes in patients with chronic liver diseases

The prevalence and mortality of diabetes mellitus and liver disease have risen in recent years. The liver plays an important role in glucose homeostasis, and various chronic liver diseases have a negative effect on glucose metabolism with the consequent emergence of diabetes. Some aspects related to chronic liver disease can affect diagnostic tools and the monitoring of diabetes and other glucose metabolism disorders, and clinicians must be aware of these limitations in their daily practice. In cirrhotic patients, fasting glucose may be normal in up until 23% of diabetes cases, and glycated hemoglobin provides falsely low results, especially in advanced cirrhosis. Similarly, the performance of alternative glucose monitoring tests, such as fructosamine, glycated albumin and 1,5-anhydroglucitol, also appears to be suboptimal in chronic liver disease. This review will examine the association between changes in glucose metabolism and various liver diseases as well as the particularities associated with the diagnosis and monitoring of diabetes in liver disease patients. Alternatives to routinely recommended tests will be discussed.

Role of gut microbiota and oxidative stress in the progression of non-alcoholic fatty liver disease to hepatocarcinoma: Current and innovative therapeutic approaches

Non-alcoholic fatty liver disease (NAFLD) represents the most common chronic liver disease in industrialized countries. NAFLD progresses through the inflammatory phase of non-alcoholic steatohepatitis (NASH) to fibrosis and cirrhosis, with some cases developing liver failure or hepatocellular carcinoma (HCC). Liver biopsy remains the gold standard approach to a definitive diagnosis of NAFLD and the distinction between simple steatosis and NASH. The pathogenesis of NASH is still not clear. Several theories have been proposed ranging from the "Two Hit Theory" to the "Multiple Hit Theory". However, the general consensus is that the gut microbiota, oxidative stress, and mitochondrial damage play key roles in the pathogenesis of NASH. The interaction between the gut epithelia and some commensal bacteria induces the rapid generation of reactive oxygen species (ROS). The main goal of any therapy addressing NASH is to reverse or prevent progression to liver fibrosis/cirrhosis. This problem represents the first "Achilles' heel" of the new molecules being evaluated in most ongoing clinical trials. The second is the inability of these molecules to reach the mitochondria, the primary sites of energy production and ROS generation. Recently, a variety of non-pharmacological and pharmacological treatment approaches for NASH have been evaluated including vitamin E, the thiazolidinediones, and novel molecules related to NASH pathogenesis (including obeticholic acid and elafibranor). Recently, a new isoform of human manganese superoxide dismutase (MnSOD) was isolated and obtained in a synthetic recombinant form designated rMnSOD. This protein has been shown to be a powerful antioxidant capable of mediating ROS dismutation, penetrating biological barriers via its uncleaved leader peptide, and reducing portal hypertension and fibrosis in rats affected by liver cirrhosis. Based on these distinctive characteristics, it can be hypothesized that this novel recombinant protein (rMnSOD) potentially represents a new and highly efficient adjuvant therapy to counteract the progression from NASH to HCC.

Co-exposure to benzo[a]pyrene and ethanol induces a pathological progression of liver steatosis in vitro and in vivo

Hepatic steatosis (i.e. lipid accumulation) and steatohepatitis have been related to diverse etiologic factors, including alcohol, obesity, environmental pollutants. However, no study has so far analyzed how these different factors might interplay regarding the progression of liver diseases. The impact of the co-exposure to the environmental carcinogen benzo[a]pyrene (B[a]P) and the lifestyle-related hepatotoxicant ethanol, was thus tested on in vitro models of steatosis (human HepaRG cell line; hybrid human/rat WIF-B9 cell line), and on an in vivo model (obese zebrafish larvae). Steatosis was induced prior to chronic treatments (14, 5 or 7 days for HepaRG, WIF-B9 or zebrafish, respectively). Toxicity and inflammation were analyzed in all models; the impact of steatosis and ethanol towards B[a]P metabolism was studied in HepaRG cells. Cytotoxicity and expression of inflammation markers upon co-exposure were increased in all steatotic models, compared to non steatotic counterparts. A change of B[a]P metabolism with a decrease in detoxification was detected in HepaRG cells under these conditions. A prior steatosis therefore enhanced the toxicity of B[a]P/ethanol co-exposure in vitro and in vivo; such a co-exposure might favor the appearance of a steatohepatitis-like state, with the development of inflammation. These deleterious effects could be partly explained by B[a]P metabolism alterations.

Return-to-health effect of modern combined antiretroviral therapy potentially predisposes HIV patients to hepatic steatosis

Prevalence and risk factors for hepatic steatosis (HS) in the human immunodeficiency virus (HIV)-positive population of western countries are controversially discussed and potentially confounded by coinfection with viral hepatitis. Significant HS (more than 10% of hepatocytes) can be accurately assessed using controlled attenuation parameter (CAP) determination. Aim of this study was to assess prevalence and factors associated with significant HS in HIV monoinfected patients.A total of 364 HIV-infected patients (289 monoinfected) were included in this prospective, cross-sectional study. All patients underwent CAP determination. Steatosis was classified as S1 (significant steatosis) with CAP > 238 dB/m, S2 with CAP > 260 dB/m, and S3 with CAP > 292 dB/m. Multivariable logistic regression analyses were performed to assess the factors associated with HS in this cohort.Significant HS was detected in 118 monoinfected patients (149 in the total cohort). In the total cohort as well as in the monoinfected patients alone, HS grade distribution showed a similar pattern (S1:29%, S2:34%, and S3:37%). Interestingly, patients with HS had a longer history of HIV infection and combined antiretroviral therapy (cART). Interalia, age, gender, ethnicity, and metabolic factors were strongly associated with HS, while body mass index (BMI), triglyceride, and glycated hemoglobin (HbA1c) levels were independently associated with significant HS.HS is highly prevalent among HIV monoinfected patients. Although metabolic risk factors, such as obesity and poorly controlled diabetes, are independently associated with HS in HIV monoinfected patients, cART and control of HIV seem to play an indirect role in the development of HS, probably through the return-to-health effect.

Olive oil lessened fatty liver severity independent of cardiometabolic correction in patients with non-alcoholic fatty liver disease: A randomized clinical trial

OBJECTIVES

Olive oil has health benefits for the correction of metabolic diseases. We aimed to evaluate the effect of olive oil consumption on the severity of fatty liver and cardiometabolic markers in patients with non-alcoholic fatty liver disease.

METHODS

This randomized, double-blind, clinical trial was conducted on 66 patients with non-alcoholic fatty liver disease. Patients were divided to receive either olive or sunflower oil, each 20 g/d for 12 wk. A hypocaloric diet (-500 kcal/d) was recommended to all participants. Fatty liver grade, liver enzymes, anthropometric parameters, blood pressure, serum lipid profile, glucose, insulin, malondialdehyde, total antioxidant capacity, and interleukin-6 were assessed pre- and postintervention.

RESULTS

Fatty liver grade, weight, waist circumference, and blood pressure significantly decreased in both groups. Sunflower oil significantly reduced serum aspartate and alanine aminotransferases and olive oil only decreased serum aspartate aminotransferase. Fat-free mass and skeletal muscle mass significantly reduced after the consumption of sunflower oil and serum triacylglycerols and fat mass significantly declined after the ingestion of olive oil. Among these variables, only changes in fatty liver grade (-0.29 ± 0.46 in sunflower oil versus -0.75 ± 0.45 in olive oil; P < 0.001), skeletal muscle mass (-0.71 ± 1.36 in sunflower oil versus +0.45 ± 2.8 in olive oil; P = 0.04), and body fat percentage (+0.38 ± 5.2% in sunflower oil versus -3.4 ± 5.5% in olive oil; P = 0.04) were significantly different between the groups.

CONCLUSIONS

Olive oil may alleviate the severity of fatty liver independent of correcting cardiometabolic risk factors. Low-calorie diets may benefit patients with non-alcoholic fatty liver disease additionally through mitigation of obesity, blood pressure, and liver enzymes.

Serum autotaxin levels are correlated with hepatic fibrosis and ballooning in patients with non-alcoholic fatty liver disease

AIM

To examine the relationship between serum autotaxin (ATX) concentrations and clinicopathological findings in non-alcoholic fatty liver disease (NAFLD) patients.

METHODS

One hundred eighty-six NAFLD patients who had undergone liver biopsy between 2008 and 2017 were retrospectively enrolled. Serum samples were collected at the time of biopsy and ATX was measured by enzyme immunoassays. Sera obtained from 160 healthy, non-obese individuals were used as controls. Histological findings were graded according to an NAFLD scoring system and correlations with serum ATX were calculated by Spearman's test. Diagnostic accuracy was evaluated using the area under the receiver operating characteristic curve (AUC). Cut-off values were identified by the Youden index, and the nearest clinically applicable value to the cutoff was considered the optimal threshold for clinical convenience.

RESULTS

Serum ATX levels were significantly higher in NAFLD patients than in controls (0.86 mg/L vs 0.76 mg/L, P < 0.001) and correlated significantly with ballooning score and fibrosis stage (r = 0.36, P < 0.001 and r = 0.45, P < 0.001, respectively). Such tendencies were stronger in female patients. There were no remarkable relationships between ATX and serum alanine aminotransferase, lipid profiles, or steatosis scores. The AUC values of ATX for predicting the presence of fibrosis (≥ F1), significant fibrosis (≥ F2), severe fibrosis (≥ F3), and cirrhosis (F4), were all more than 0.70 in respective analyses.

CONCLUSION

Serum ATX levels may at least partially reflect histological severity in NAFLD.

Clinicopathological and immunological characteristics and outcome of concomitant coeliac disease and non-alcoholic fatty liver disease in adults: a large prospective longitudinal study

Objective

Concomitant non-alcoholic fatty liver disease (NAFLD) and coeliac disease (CD) have not been adequately studied. This study investigated the frequency of CD among NAFLD patients and the clinicopathological and immunological patterns and outcome of concomitant NAFLD and CD.

Design

This prospective longitudinal study screened patients with NAFLD for CD (tissue transglutaminase antibodies (TTGA); anti-TTGA and antiendomysial antibodies (EMA)). Patients with concomitant NAFLD and CD and patients with either NAFLD or CD were enrolled and followed. Duodenal biopsy, transient elastography, tumour necrosis factor (TNF)-alpha, transforming growth factor-beta, interleukins (ILs) 1, 6, 10, 15 and 17, folic acid and vitamins B12 and D were performed at baseline and 1 year after gluten-free diet (GFD).

Results

CD was confirmed in 7.2% of patients with NAFLD. Refractory anaemia and nutritional deficiencies were frequent in patients with concomitant NAFLD and CD who had advanced intestinal and hepatic lesions, higher levels of TNF-α, IL-15 and IL-17 compared with patients with CD and NAFLD. Patients concomittant CD and NAFLD showed clinical response to GFD, but intestinal histological improvement was suboptimal. Combining EMA-IgA or anti-TTGA with either IL-15 or IL-17 enhances the prognostic performance of both tests in predicting histological response to GFD.

Conclusion

Concomitant NAFLD and CD is not uncommon. Recurrent abdominal symptoms, refractory anaemia, nutritional deficiencies in patients with NAFLD warrant screening for CD. The study has important clinical implications since failure in diagnosing CD in patients with NAFLD patients results in marked intestinal and hepatic damage and suboptimal response to GFD that can be alleviated by early diagnosis and initiation of GFD.

Components of metabolic syndrome increase the risk of mortality in nonalcoholic fatty liver disease (NAFLD)

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the United States. Metabolic syndrome (MS) components are highly prevalent in NAFLD. Our aim is to assess the relationship of NAFLD and MS with long-term outcome of mortality.The Third National Health and Nutrition Examination Survey (NHANES) was utilized. NAFLD was diagnosed by ultrasound in the presence of hepatic steatosis and no other causes of chronic liver disease. History of MS and its components were obtained from self-reported NHANES questionnaires. Mortality was obtained from Mortality-Linkage File, through December 31, 2011. Chi-square test was used for categorical variables and Cox proportional models estimated hazard ratios with 95% confidence interval.NAFLD cohort (n = 3613) had a median age of 43 years, 73% white, and 50% male. NAFLD group with at least one MS condition was significantly older, had higher body mass index, more likely to have insulin resistance, and heart disease compared to NAFLD group without MS. Over 19-years of follow-up, 1039 people died. Compared to NAFLD patients without MS, presence of one MS component increased the risk of mortality at 8-year (2.6% vs 4.7%) and 16-year (6% vs 11.9%) (P < .001). After adjusting for socio-demographic factors, NAFLD with all MS components was associated with overall, cardiac and liver-mortality. Increased number of MS components was associated with lower survival (P < .0001).Patients with NAFLD and MS have higher mortality risk compared to NAFLD patients without MS. These NAFLD patients should be prioritized for the development of treatment regimens.

Alogliptin alleviates hepatic steatosis in a mouse model of nonalcoholic fatty liver disease by promoting CPT1a expression via Thr172 phosphorylation of AMPKα in the liver

Pioglitazone (PIO) has been reported to be effective for nonalcoholic fatty liver disease (NAFLD) and alogliptin (ALO) may have efficacy against NAFLD progression in patients with type 2 diabetes mellitus (T2DM). The present study examined the effectiveness of ALO in a rodent model of NAFLD and diabetes mellitus. KK‑Ay mice were used to produce an NAFLD model via administration of a choline‑deficient (CD) diet. To examine the effects of alogliptin, KK‑Ay mice were provided with a CD diet with 0.03% ALO and/or 0.02% PIO orally for 8 weeks. Biochemical parameters, pathological alterations and hepatic mRNA levels associated with fatty acid metabolism were assessed. Severe hepatic steatosis was observed in KK‑Ay mice fed with a CD diet, which was alleviated by the administration of ALO and/or PIO. ALO administration increased the hepatic carnitine palmitoyltransferase 1a (CPT1a) mRNA expression level and enhanced the Thr172 phosphorylation of AMP‑activated protein kinase α (AMPKα) in the liver. PIO administration tended to decrease the hepatic fatty acid synthase mRNA expression level and increase the serum adiponectin level. Homeostasis model of assessment‑insulin resistance values tended to improve with ALO and PIO administration. ALO and PIO alleviated hepatic steatosis in KK‑Ay mice fed with a CD diet. ALO increased hepatic mRNA expression levels associated with fatty acid oxidation. In addition, the results of the present study suggested that ALO promotes CPT1a expression via Thr172 phosphorylation of AMPKα.

Nonalcoholic fatty liver disease, cholesterol gallstones, and cholecystectomy: new insights on a complex relationship

PURPOSE OF REVIEW

Gallstone disease (GSD) and nonalcoholic fatty liver disease (NAFLD often coexist in a given patient and both conditions are associated to obesity and insulin resistance. The relationship between GSD and NAFLD is complex and bidirectional. In the present review, we summarize the existing information on the complex link between GSD and NAFLD and the potential implications for patient care.

RECENT FINDINGS

Several clinical studies and systematic reviews have addressed the association between NAFLD and GSD underscoring that NAFLD is an independent risk factor for GSD. Conversely, GSD has been found also to be an independent risk factor for NAFLD with GSD potentially being linked to greater disease severity. In addition to the data showing association of NAFLD and GSD, recent evidence has also showed that cholecystectomy may itself be a risk factor for NAFLD development. The complex and bidirectional relationship between these diseases is partially explained by a number of common pathogenic links but the precise underlying mechanisms of the association of GSD and NAFLD need to be better delineated. Also, although the mechanisms of the promotional effect of cholecystectomy on NAFLD development are unknown, recent findings unveiling new aspects of gallbladder physiology and endocrine actions of bile acids provide a framework to advance research in this field.

SUMMARY

In this review, we address the different aspects of the complex association between NAFLD and GSD. The potential underlying mechanisms and recent information on endocrine actions of bile acids and the gallbladder are reviewed.

Radiologic Imaging in Nonalcoholic Fatty Liver Disease and Nonalcoholic Steatohepatitis

The article reviews the multimodality (ultrasound, computed tomography, and magnetic resonance [MR]) imaging appearance of nonalcoholic fatty liver disease (NAFLD) and discusses the radiologic diagnostic criteria as well as the sensitivity and specificity of these imaging methods. The authors review the role of both ultrasound and MR elastography for the diagnosis of fibrosis and for the longitudinal evaluation of patients following therapeutic intervention. Lastly, the authors briefly discuss the screening and diagnosis of hepatocellular carcinoma in patients with NAFLD, as there are special considerations in this population.

Diet switch and omega-3 hydroxy-fatty acids display differential hepatoprotective effects in an obesity/nonalcoholic fatty liver disease model in mice

AIM

To study the effect of 18-hydroxy-eicosapentaenoic acid (18-HEPE) and 17-hydroxy-docosahexaenoic acid (17-HDHA) in a murine model of obesity/nonalcoholic fatty liver disease.

METHODS

C57BL/6 mice were fed with standard chow diet (CD) or high-fat, fructose-enriched diet (HFD) for 16 wk. Then, three groups were treated for 14 d with either, diet switch (HFD for CD), 18-HEPE, or 17-HDHA. Weight and fasting glucose were recorded on a weekly basis. Insulin tolerance test was performed at the end of treatment. Histological analysis (HE and Masson’s trichrome stain) and determination of serum insulin, glucagon, glucagon-like peptide 1 (GLP-1), glucose-dependent insulinotropic polypeptide, adiponectin and resistin were carried out as well as liver proteins by western blot.

RESULTS

Mice treated with hydroxy-fatty acids 18-HEPE and 17-HDHA displayed no weight loss or improved insulin sensitivity. However, these mice groups showed a significant amelioration on serum GLP-1, adiponectin and resistin levels. Also, a significant reduction on inflammatory infiltrate was observed at both portal and lobular zones. Furthermore, up-regulation of PPARα/γ protein levels was observed in liver tissue and it was associated with decreased levels of NF-κB also determined by western blot analysis. On the other hand, diet switch regimen resulted in a marked improvement in most parameters including: weight loss, increased insulin sensitivity, decreased steatosis, restored levels of insulin, glucagon, leptin, adiponectin and resistin. However, no significant changes were observed regarding inflammatory infiltrate in this last group.

CONCLUSION

18-HEPE and 17-HDHA differentially exert hepatoprotective effects through up-regulation of nuclear receptors PPARα/γ and amelioration of serum adipokines profile.

Epigenetically mediated inhibition of S-adenosylhomocysteine hydrolase and the associated dysregulation of 1-carbon metabolism in nonalcoholic steatohepatitis and hepatocellular carcinoma

The substantial rise in the prevalence of nonalcoholic steatohepatitis (NASH), an advanced form of nonalcoholic fatty liver disease, and the strong association between NASH and the development of hepatocellular carcinoma indicate the urgent need for a better understanding of the underlying mechanisms. In the present study, by using the Stelic animal model of NASH and NASH-derived liver carcinogenesis, we investigated the role of the folate-dependent 1-carbon metabolism in the pathogenesis of NASH. We demonstrated that advanced NASH and NASH-related liver carcinogenesis are characterized by a significant dysregulation of 1-carbon homeostasis, with diminished expression of key 1-carbon metabolism genes, especially a marked inhibition of the S-adenosylhomocysteine hydrolase ( Ahcy) gene and an increased level of S-adenosyl-l-homocysteine (SAH). The reduction in Ahcy expression was associated with gene-specific cytosine DNA hypermethylation and enrichment of the gene promoter by trimethylated histone H3 lysine 27 and deacetylated histone H4 lysine 16, 2 main transcription-inhibiting markers. These results indicate that epigenetically mediated inhibition of Ahcy expression may be a driving force in causing SAH elevation and subsequent downstream disturbances in transsulfuration and transmethylation pathways during the development and progression of NASH.-Pogribny, I. P., Dreval, K., Kindrat, I., Melnyk, S., Jimenez, L., de Conti, A., Tryndyak, V., Pogribna, M., Ortega, J. F., James, S. J., Rusyn, I., Beland, F. A. Epigenetically mediated inhibition of S-adenosylhomocysteine hydrolase and the associated dysregulation of 1-carbon metabolism in nonalcoholic steatohepatitis and hepatocellular carcinoma.

Role of Inflammasomes in the Development of Gastrointestinal Diseases

Many diseases of the gastrointestinal tract have been attributed to chronic inflammation, and a few have identified the role of inflammasomes in their pathogenesis. Inflammasomes are a group of protein complexes comprising of several intracellular proteins that link the sensing of microbial products and metabolic stress to the proteolytic activation of the proinflammatory cytokines. Recent studies have implicated activation of several families of NOD-like receptors (NLRs) which are major components of inflammasomes in the development and exacerbation of many diseases of human systems. In this chapter, we discuss the role of inflammasomes in some of the most prevalent diseases of the gastrointestinal tract and highlight potential targets for treatment.