Diagnosis and therapy of nonalcoholic steatohepatitis

Pin1 Exacerbates Non-Alcoholic Fatty Liver Disease by Enhancing Its Activity through Binding to ACC1

Non-alcoholic fatty liver disease (NAFLD) is a clinicopathological syndrome characterized by diffuse hepatocellular steatosis due to fatty deposits in hepatocytes, excluding alcohol and other known liver injury factors. However, there are no specific drugs for the clinical treatment of NAFLD. Therefore, research on the pathogenesis of NAFLD at the cellular and molecular levels is a promising approach to finding therapeutic targets and developing targeted drugs for NAFLD. Pin1 is highly expressed during adipogenesis and contributes to adipose differentiation, but its specific mechanism of action in NAFLD is unclear. In this study, we investigated the role of Pin1 in promoting the development of NAFLD and its potential mechanisms in vitro and in vivo. First, Pin1 was verified in the NAFLD model in vitro using MCD diet-fed mice by Western Blot, RT-qPCR and immunohistochemistry (IHC) assays. In the in vitro study, we used the oleic acid (OA) stimulation-induced lipid accumulation model and examined the lipid accumulation in each group of cells by oil red O staining as well as BODIPY staining. The results showed that knockdown of Pin1 inhibited lipid accumulation in hepatocytes in an in vitro lipid accumulation model and improved lipid indices and liver injury levels. Moreover, in vivo, WT and Pin1-KO mice were fed a methionine-choline deficient (MCD) diet for 4 weeks to induce the NAFLD model. The effects of Pin1 on lipid accumulation, hepatic fibrosis, and oxidative stress were evaluated by biochemical analysis, glucose and insulin tolerance tests, histological analysis, IHC, RT-qPCR and Western blot assays. The results indicate that Pin1 knockdown significantly alleviated hepatic steatosis, fibrosis and inflammation in MCD-induced NAFLD mice, improved glucose tolerance and alleviated insulin resistance in mice. Further studies showed that the AMPK/ACC1 signalling pathway might take part in the process by which Pin1 regulates NAFLD, as evidenced by the inhibition of the AMPK/ACC1 pathway. In addition, immunofluorescence (IF), coimmunoprecipitation (Co-IP) and GST pull-down experiments also showed that Pin1 interacts directly with ACC1 and inhibits ACC1 phosphorylation levels. Our study suggests that Pin1 promotes NAFLD progression by inhibiting the activation of the AMPK/ACC1 signalling pathway, and it is possible that this effect is achieved by Pin1 interacting with ACC1 and inhibiting the phosphorylation of ACC1.

Potential therapeutic implications of histidine catabolism by the gut microbiota in NAFLD patients with morbid obesity

The gut microbiota contributes to the pathophysiology of non-alcoholic fatty liver disease (NAFLD). Histidine is a key energy source for the microbiota, scavenging it from the host. Its role in NAFLD is poorly known. Plasma metabolomics, liver transcriptomics, and fecal metagenomics were performed in three human cohorts coupled with hepatocyte, rodent, and Drosophila models. Machine learning analyses identified plasma histidine as being strongly inversely associated with steatosis and linked to a hepatic transcriptomic signature involved in insulin signaling, inflammation, and trace amine-associated receptor 1. Circulating histidine was inversely associated with Proteobacteria and positively with bacteria lacking the histidine utilization (Hut) system. Histidine supplementation improved NAFLD in different animal models (diet-induced NAFLD in mouse and flies, ob/ob mouse, and ovariectomized rats) and reduced de novo lipogenesis. Fecal microbiota transplantation (FMT) from low-histidine donors and mono-colonization of germ-free flies with Enterobacter cloacae increased triglyceride accumulation and reduced histidine content. The interplay among microbiota, histidine catabolism, and NAFLD opens therapeutic opportunities.

Serum vitamin D is associated with ultrasound-defined hepatic fibrosis

BACKGROUND

Evidences from population-based investigations on the exact relationship between vitamin D and the severity of liver fibrosis remain debated and conflicting. Here, we aim to explore the relationship between serum vitamin D and ultrasound-defined advanced hepatic fibrosis in the US participants with nonalcoholic fatty liver disease (NAFLD).

METHODS

In the retrospective study, individuals with intact information on interesting variables from the 2017-2018 National Health and Nutrition Examination Survey (NHANES) were included. NAFLD was diagnosed on the basis of controlling attenuation parameter (CAP) value≥ 274 dB/m without causes of other chronic hepatic diseases. We identified advanced fibrosis grades (F2) by liver stiffness measurement (LSM) score of ≥ 8.2 kPa in NAFLD patients. The impact of elevated serum vitamin D on the prevalence of hepatic fibrosis was assessed by multivariate logistic regression models on the basis of the NHANES recommended weights.

RESULTS

The study involved 1624 subjects with NAFLD in total, and 305 (18.28 %, weighted%) of whom were diagnosed with advanced hepatic fibrosis according to the definition based on parameters obtained from vibration controlled transient elastography (VCTE). In the multivariate logistic regression analysis, serum vitamin D presented a negative relationship to hepatic fibrosis with lower odds in patients with hepatic steatosis after being adjusted for potential confounding factors (fully adjusted: OR=0.47, 95 % CI: 0.24-0.90, p = 0.034). Our subgroup analysis revealed that the inverse relationship was still existed in males (fully adjusted: OR = 0.34, 95 % CI: 0.17-0.70, p = 0.014), non-obese subjects (fully adjusted: OR = 0.20, 95 % CI: 0.04-0.89, p = 0.042) and participants below 60 years (fully adjusted: OR = 0.43, 95 % CI: 0.21-0.90, p = 0.033), whereas in models adjusted for the potential confounding factors, no statistically significant correlation was noted in females, obese subjects or subjects with age≥ 60 years.

CONCLUSIONS

This large population-based investigation indicated that elevated serum vitamin D reduced the onset of advanced fibrosis diagnosed by ultrasound in males, non-obese subjects and younger participants with NAFLD.

Triglyceride glucose-waist circumference: the optimum index to screen nonalcoholic fatty liver disease in non-obese adults

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is easily neglected in the non-obese population. TyG index (triglyceride glucose Index) and TG/HDL-c (triglyceride to high-density lipoprotein cholesterol) are new indicators to evaluate insulin resistance (IR). Fibroscan is a non-invasive way to assess hepatic steatosis [by control attenuation parameters (CAP)] and fibrosis [by liver stiffness measurement (LSM)].The purpose of this study was to explore the correlation of TyG and its combination with obesity indicators [TyG-waist circumference (WC), TyG-body mass index (BMI)] and TG/HDL-c with CAP and LSM.

METHOD

One thousand seven hundred seventy-six adults (age ≥ 20 years, BMI < 30 kg/m2) in the National Health and Nutrition Examination Survey (NHANES) 2017-2018 were included. The correlations of CAP and LSM to the indexes were assessed by generalized linear models.. Receiver operating characteristic (ROC) curve was performed to evaluate the diagnostic capability of the indicators on NAFLD and liver stiffness.

RESULTS

Survey-weighted percentage of NAFLD in non-obese was 38.6%. In the fully adjusted models, there were positive associations of TyG, TyG-BMI, TyG-WC and TG/HDL-c to CAP, with the βs of 24.810, 0.704, 0.29 and 2.983 (all p < 0.05), respectively. There were positive associations of TyG, TyG-BMI, TyG-WC, and TG/HDL-c to NAFLD, with ORs of 3.387, 1.03, 1.010 and 1.281 ((all p < 0.05)).The positive association was detected for TG/HDL-c and TyG-WC and LSM with βs of 0.057 and 0.004(p = 0.021 and p = 0.003).TyG-WC were positively associated with liver stiffness with OR of 1.006(95%CI = 1.002, 1.012). Furthermore, the TyG-WC had the strongest diagnostic capability (ROC = 0.806; 95%CI: 0.785-0.826) on NAFLD in non-obese participants, with a specificity of 0.737 and sensitivity of 0.746.

CONCLUSION

In US non-obese population, the TyG, TyG-BMI, TyG-WC, and TG/HDL-c are positively correlated with CAP and NAFLD. TyG-WC has clinical importance in identifying NAFLD in the non-obese population.

Impact of nonalcoholic fatty liver disease-related metabolic state on depression

Nonalcoholic fatty liver disease (NAFLD), also recently referred as metabolic (dysfunction)-associated fatty liver disease (MAFLD), is characterized by hepatocyte steatosis in the setting of metabolic risk conditions and in the absence of an underlying precursor, for instance alcohol consumption, hepatotropic viruses and hepatotoxic drugs. A possible association between NAFLD and depression has been proposed, owing to intersecting pathophysiological pathways. This narrative review aimed to summarize the current evidence that illustrate the potential pathophysiological and clinical linkage between NAFLD-related metabolic state and depression. Prefrontal cortex lesions are suggested to be a consequence of liver steatosis-associated systematic hyperinflammatory state, a phenomenon also occurring in depression. In addition, depressive symptoms are present in neurotransmitter imbalances. These abnormalities seem to be correlated with NAFLD/MAFLD, in terms of insulin resistance (IR), ammonia and gut dysbiosis' impact on serotonin, dopamine, noradrenaline levels and gamma aminobutyric acid receptors. Furthermore, reduced levels of nesfatin-1 and copine-6-associated BDNF (brain-derived neurotrophic factor) levels have been considered as a probable link between NAFLD and depression. Regarding NAFLD-related gut dysbiosis, it stimulates mediators including lipopolysaccharides, short-chain fatty acids and bile acids, which play significant role in depression. Finally, western diet and IR, which are mainstay components of NAFLD/MAFLD, are, also, substantiated to affect neurotransmitters in hippocampus and produce neurotoxic lipids that contribute to neurologic dysfunction, and thus trigger emotional disturbances, mainly depressive symptoms.

Influence of AFP on surgical outcomes in non-B non-C patients with curative resection for hepatocellular carcinoma

To study the clinical and prognostic features of non-B non-C alpha-fetoprotein (AFP)(-)-hepatocellular carcinoma (HCC) (NBNC-AFP(-)-HCC) and the relationship between the prognostic features of HCC and hepatitis B virus surface antigen (HBsAg) status and AFP. We enrolled 227 patients who underwent hepatic resection for HCC between January 1998 and December 2007 at Sun Yat-sen University Cancer Center, all of whom were diagnosed with HCC by pathology. All patients were stratified into one of four groups (B-AFP(+)-HCC, B-AFP(-)-HCC, NBNC-AFP(+)-HCC, and NBNC-AFP(-)-HCC) according to AFP levels and HBsAg status. The clinicopathologic and survival characteristics of NBNC-AFP(-)-HCC patients were compared with those of all other three groups. Out of the 105 NBNC-HCC patients, 43 patients (40.9%) had AFP-negative HCC. There were some differences in factors between the B-AFP(+) and NBNC-AFP(-) patients, such as age, body mass index (BMI), diabetes, and ALT (P < 0.05). On univariate analysis, tumour size, secondary tumour, and portal invasion were prognostic factors for overall survival (OS) and disease-free survival (DFS) (P < 0.05). Cox multivariate regression analysis suggested that tumour size and tumour number (P < 0.05) were independent predictors. In addition, compared with the B-AFP(+)-HCC, B-AFP(-)-HCC, and NBNC-AFP(+)-HCC groups, the NBNC-AFP(-)-HCC patients had the best DFS (P < 0.05). Compared with the B-AFP(+)-HCC and NBNC-AFP(+)-HCC groups, the NBNC-AFP(-)-HCC patients had better OS (P < 0.05), and survival rates were similar to those of B-AFP(-)-HCC patients. NBNC-AFP(-)-HCC patients had a relatively favourable prognosis. It can serve as a useful marker in predicting the risk of tumour recurrence in the early stages.

Sex-specific associations of the urinary fourteen-metal mixture with NAFLD and liver fibrosis among US adults: A nationally representative study

Although previous studies have examined the hepatotoxicity of single metal exposure, the associations between metal mixture and non-alcoholic fatty liver disease (NAFLD) or fibrosis remain unclear. This study investigated the associations of urinary metal mixture with the risks of NAFLD and liver fibrosis in US adults using data from the National Health and Nutrition Examination Survey (NHANES) from 2017.01 to 2020.03. Vibration-controlled transient elastography was used to detect the controlled attenuation parameter (CAP) and liver stiffness measurement (LSM), which are indicators of NAFLD and liver fibrosis respectively. Three novel mixture modeling approaches including the Bayesian kernel machine regression (BKMR), weighted quantile sum (WQS) regression and quantile g-computation (qgcomp) were used to estimate the associations of the urinary fourteen-metal mixture with Ln CAP and Ln LSM. There were 2283 adults aged over 18 years (1209 women and 1074 men) were included. Among women, urinary metal mixture was positively associated with Ln CAP in the BKMR and qgcomp models (both P < 0.05). However, no significantly associations of urinary metal mixture with Ln CAP were observed among men in all models (all P > 0.05). The metal mixture was not associated with Ln LSM in the three models regardless of genders (all P > 0.05). In conclusion, we observed sex-specific associations between urinary metal mixture and the prevalence of NAFLD in US adults. These findings emphasize the role of environmental heavy metal exposure in the development of NAFLD, and confirm the need for more prospective cohort studies on sex-specific manner.

Associations of phthalates with NAFLD and liver fibrosis: A nationally representative cross-sectional study from NHANES 2017 to 2018

OBJECTIVE

Although phthalates are common environmental pollutants, few studies have focused on the relationship of phthalates exposure with non-alcoholic fatty liver disease (NAFLD) or liver fibrosis, and especially, the alternative phthalates have been questioned in recent years about whether they are better choices. Thus, this study aimed to explore the associations of exposure to major phthalates or alternative phthalates with NAFLD and liver fibrosis.

METHODS

Data of 1450 adults from the National Health and Nutrition Examination Survey (NHANES) 2017-2018 were collected. The urinary metabolite concentrations of di-2-ethylhexyl phthalate (DEHP), diisononyl phthalate (DINP) and diisodecyl phthalate (DIDP) were detected. Controlled attenuation parameter (CAP) and median liver stiffness measurement (LSM) were acquired for quantitative diagnosis of NAFLD and liver fibrosis by vibration-controlled transient elastography. Multivariate logistic regression analysis and linear regression analysis were performed to examine the associations between phthalates and NAFLD and liver fibrosis.

RESULTS

After adjustment of the potential factors, the prevalence of NAFLD was significantly elevated among those in the fourth quartile of mono-(2-ethyl-5-carboxypentyl) phthalate (OR, 95%CI = 2.719, 1.296, 5.700, P = 0.016), mono (2-ethyl-5-hydroxyhexyl) phthalate (OR, 95%CI = 2.073, 1.111, 3.867, P = 0.037). No significant association was found between the alternative phthalates and NAFLD. The similar result was gained by linear regression analysis that MECPP was still significantly associated with Ln CAP (Q4 vs. Q1: β, 95%CI = 0.067, 0.017, 0.118, P = 0.027). After adjustment for the same covariates, no significant association between phthalates and liver fibrosis was found in logistics regression analysis.

CONCLUSIONS

All in all, higher prevalence of NAFLD is correlated with DEHP but not DINP or DIDP in American adults. There is no significant relationship between phthalates and liver fibrosis defined as LSM ≥ 8 Kpa. Nevertheless, further research is needed to provide evidence of causality.

Clinical Relevance of Selenium with Liver Stiffness and Steatosis Detected by Transient Elastography in Adults

The associations between selenium and liver stiffness and steatosis remain uncertain. This study aimed to explore the clinical relevance of selenium with liver stiffness and steatosis in adults from the 2017-2018 National Health and Nutrition Examination Survey. Subjects with excessive alcohol consumption and hepatitis B or C infection were excluded. Liver stiffness and steatosis were detected by transient elastography. Dietary selenium intakes and blood selenium concentrations were included as exposures. In multivariate analysis without adjustment for obesity, higher dietary selenium intakes (tertile 3 vs. tertile 1) were positively associated with liver stiffness in females (odds ratio (95% confidence interval): 2.64 (1.88-3.70)), and were positively associated with liver steatosis overall (1.54 (1.20-1.97)) and also in males (1.55 (1.06-2.26)). In multivariate analysis without adjustment for obesity, higher blood selenium concentrations (tertile 3 vs. tertile 1) were positively associated with liver steatosis overall (1.33 (1.02-1.76)) and also in males (1.56 (1.13-2.16)). After further adjustment for obesity, the abovementioned associations remain significant between dietary selenium intakes and liver stiffness in females (2.29 (1.69-3.12)) and liver steatosis overall (1.37 (1.01-1.86)), and between blood selenium concentrations and liver steatosis in males (1.67 (1.25-2.21)). Dose-response analysis showed that the abovementioned associations were linear. However, dietary selenium intakes meeting the recommended daily allowance (≥ 55 µg/day) were not associated with liver stiffness (0.99 (0.62-1.55)) and steatosis (1.01 (0.69-1.49)). In conclusion, higher dietary selenium intakes and blood selenium concentrations were positively associated with liver stiffness and steatosis, and obesity may partially account for the observed associations.

Accurate and generalizable quantitative scoring of liver steatosis from ultrasound images via scalable deep learning

BACKGROUND

Hepatic steatosis is a major cause of chronic liver disease. Two-dimensional (2D) ultrasound is the most widely used non-invasive tool for screening and monitoring, but associated diagnoses are highly subjective.

AIM

To develop a scalable deep learning (DL) algorithm for quantitative scoring of liver steatosis from 2D ultrasound images.

METHODS

Using multi-view ultrasound data from 3310 patients, 19513 studies, and 228075 images from a retrospective cohort of patients received elastography, we trained a DL algorithm to diagnose steatosis stages (healthy, mild, moderate, or severe) from clinical ultrasound diagnoses. Performance was validated on two multi-scanner unblinded and blinded (initially to DL developer) histology-proven cohorts (147 and 112 patients) with histopathology fatty cell percentage diagnoses and a subset with FibroScan diagnoses. We also quantified reliability across scanners and viewpoints. Results were evaluated using Bland-Altman and receiver operating characteristic (ROC) analysis.

RESULTS

The DL algorithm demonstrated repeatable measurements with a moderate number of images (three for each viewpoint) and high agreement across three premium ultrasound scanners. High diagnostic performance was observed across all viewpoints: Areas under the curve of the ROC to classify mild, moderate, and severe steatosis grades were 0.85, 0.91, and 0.93, respectively. The DL algorithm outperformed or performed at least comparably to FibroScan control attenuation parameter (CAP) with statistically significant improvements for all levels on the unblinded histology-proven cohort and for “= severe” steatosis on the blinded histology-proven cohort.

CONCLUSION

The DL algorithm provides a reliable quantitative steatosis assessment across view and scanners on two multi-scanner cohorts. Diagnostic performance was high with comparable or better performance than the CAP.

Amelioratory Effect of Resistant Starch on Non-alcoholic Fatty Liver Disease via the Gut-Liver Axis

Non-alcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome with a global prevalence. Impaired gut barrier function caused by an unhealthy diet plays a key role in disrupting the immune-metabolic homeostasis of the gut-liver axis (GLA), leading to NAFLD. Therefore, dietary interventions have been studied as feasible alternative therapeutic approaches to ameliorate NAFLD. Resistant starches (RSs) are prebiotics that reduce systemic inflammation in patients with metabolic syndrome. The present review aimed to elucidate the mechanisms of the GLA in alleviating NAFLD and provide insights into how dietary RSs counteract diet-induced inflammation in the GLA. Emerging evidence suggests that RS intake alters gut microbiota structure, enhances mucosal immune tolerance, and promotes the production of microbial metabolites such as short-chain fatty acids (SCFAs) and secondary bile acids. These metabolites directly stimulate the growth of intestinal epithelial cells and elicit GPR41/GPR43, FXR, and TGR5 signaling cascades to sustain immune-metabolic homeostasis in the GLA. The literature also revealed the dietary-immune-metabolic interplay by which RSs exert their regulatory effect on the immune-metabolic crosstalk of the GLA and the related molecular basis, suggesting that dietary intervention with RSs may be a promising alternative therapeutic strategy against diet-induced dysfunction of the GLA and, ultimately, the risk of developing NAFLD.

The role of Resolvin D1 in liver diseases

The liver is a parenchymatous organ closely related to immunity, detoxification and metabolism of the three major nutrients. The inflammatory response is a protective mechanism of the body to eliminate harmful stimuli. However, continuous inflammatory stimulation leads to occurrence of many liver diseases and brings great social burden. Resolvin D1, a member of the specialized pro-resolving lipid mediators family, exerts anti-inflammatory, anti-oxidant stress, anti-fibrosis, anti-apoptotic, and anti-tumor effects by binding to ALX/FPR2 or GPR32. RvD1 plays an important role and has great therapeutic potential in liver diseases, which has been validated in multiple models of preclinical disease. This review will provide a detailed summary of the role of RvD1 in different liver diseases, including acute liver injury, liver ischemia/reperfusion injury, non-alcoholic fatty liver disease, liver fibrosis, and liver cancer, so as to help people have a more comprehensive understanding of RvD1 and promote its further research.

Models to Predict Development or Recurence of Hepatocellular Carcinoma (HCC) in Patients with Advanced Hepatic Fibrosis

Purpose of Review

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death in the United States (U.S.).¹ The purpose of this review is to highlight published models that predict development of HCC and estimate risk of HCC recurrence after treatments.

Recent Findings

There have been several models created for both de novo HCC and HCC recurrence, with the more recent models using a combination of age, sex, decompensation, and laboratory values (platelet count, albumin, bilirubin), and liver disease etiology to predict both 5 and 10-year HCC incidence. For chronic hepatitis C, sustained virologic response has been a useful component of understanding HCC risk reduction. BMI and diabetes have been utilized in non-alcoholic fatty liver disease (NAFLD) models to predict HCC risk. For HCC recurrence after treatment (for both surgical resection and liver transplant), tumor size and number, vascular invasion, alpha-fetoprotein (AFP) and neutrophil to lymphocyte ratio (NLR) are all components of HCC recurrence risk models.

Summary

Although numerous HCC risk prediction models have been established over the last several years, challenges remain including how to best incorporate these models into clinical practice, improve surveillance for NAFLD-HCC development, and determine timing and duration of post-resection recurrence surveillance.

Hepatic galectin-3 is associated with lipid droplet area in non-alcoholic steatohepatitis in a new swine model

Non-alcoholic fatty liver disease (NAFLD) is currently a growing epidemic disease that can lead to cirrhosis and hepatic cancer when it evolves into non-alcoholic steatohepatitis (NASH), a gap not well understood. To characterize this disease, pigs, considered to be one of the most similar to human experimental animal models, were used. To date, all swine-based settings have been carried out using rare predisposed breeds or long-term experiments. Herein, we fully describe a new experimental swine model for initial and reversible NASH using cross-bred animals fed on a high saturated fat, fructose, cholesterol, cholate, choline and methionine-deficient diet. To gain insight into the hepatic transcriptome that undergoes steatosis and steatohepatitis, we used RNA sequencing. This process significantly up-regulated 976 and down-regulated 209 genes mainly involved in cellular processes. Gene expression changes of 22 selected transcripts were verified by RT-qPCR. Lipid droplet area was positively associated with CD68, GPNMB, LGALS3, SLC51B and SPP1, and negatively with SQLE expressions. When these genes were tested in a second experiment of NASH reversion, LGALS3, SLC51B and SPP1 significantly decreased their expression. However, only LGALS3 was associated with lipid droplet areas. Our results suggest a role for LGALS3 in the transition of NAFLD to NASH.

PNPLA3 genotype and fibrosis-4 index predict cardiovascular diseases of Japanese patients with histopathologically-confirmed NAFLD

Background

Reliable noninvasive predictors of the top three causes of death [cardiovascular diseases (CVDs), malignancies, and liver-related events in patients with non-alcoholic fatty liver disease (NAFLD)] have not yet been determined.

Methods

We retrospectively investigated the incidence of three complications [CVDs, malignancy (except for liver cancer), and liver-related events] in 477 Japanese patients with histo-pathologically confirmed NAFLD for a median follow-up of 5.9 years. In addition to histological findings, we also investigated noninvasive predictors.

Results

A score of ≥ 2.67 for the noninvasive diagnosis of stage 4 fibrosis based on the Fibrosis-4 (FIB-4) index indicated a high level area under the receiver operating characteristic (AUROC) curve (0.90), sensitivity (82.9%), specificity (86.4%), and negative predictive value [(NPV) of 98.5%]. The yearly incidence rates of CVDs, malignancies, and liver-related events were found to be 1.04%, 0.83%, and 0.30%, respectively. Multivariate analysis identified a FIB-4 index ≥ 2.67 score as a significant and independent, noninvasive predictor of these three complications. Furthermore, the cumulative incidence rates of CVDs were significantly different among the three genotypes of PNPLA3. PNPLA3 genotype CC, chronic kidney disease (CKD), and FIB-4 index ≥ 2.67 was could be attributed to these three significant CVD risk factors. The rates of CVDs were significantly different among the three subgroups based on the combination of risk factors. In malignancy (except for liver cancer), the incidence rate of colon cancer was 25.0%; in particular, the rate in females was 53.8%.

Conclusions

Our results highlighted the importance of the PNPLA3 genotype and FIB-4 index ≥ 2.67 on the incidence of complications in Japanese patients with NAFLD, especially the incidence of CVDs. Early diagnosis, based on the presence of one or more risk factors, and early treatment might improve the prognosis for NAFLD patients.

Dynamics of Circulating miR-122 Predict Liver Cancer and Mortality in Japanese Patients with Histopathologically Confirmed NAFLD and Severe Fibrosis Stage

INTRODUCTION

It is unclear whether the relationships between changes in fibrosis and circulating microRNA-122 (miR-122) dynamics might influence the prognosis of nonalcoholic fatty liver disease (NAFLD).

METHODS

This study investigates the impact of serum miR-122 dynamics and histological changes on the incidence of liver cancer and mortality in 81 Japanese NAFLD patients who underwent serial liver biopsies. The median interval between the first and second liver biopsies was 2.9 years.

RESULTS

The fibrosis stage scores indicated progression, no change, and improvement (a decrease of one point or more) in 21.0%, 56.8%, and 22.2% of the patients, respectively. There were 64 patients in the high-risk group who had no improvement in stage scores. Among these, the miR-122 levels were significantly lower in 7 patients with liver cancer than those of the 54 patients who had no liver cancer at the second liver biopsy. The cumulative rates of liver cancer were significantly higher in cases with miR-122 ratios <0.5 (serum miR-122 level at second biopsy to that at first biopsy) than those with ratios ≥0.5. The cumulative survival rates in cases with miR-122 ratios <0.5 tended to be lower than those with ratios ≥0.5. Of the 64 high-risk patients, 39 indicated stage 2 or greater (severe fibrosis stage) at the first liver biopsy and also showed similar results of cumulative liver cancer and survival rates.

CONCLUSIONS

Longitudinal examination of serial liver biopsies indicated that the circulating miR-122 dynamics might be useful in predicting the prognosis for NAFLD patients with severe fibrosis stage and no improvement of the stage scores.

Chlorella vulgaris is an effective supplement in counteracting non-alcoholic fatty liver disease-related complications through modulation of dyslipidemia, insulin resistance, and inflammatory pathways

This study was aimed to investigate the effect of microalgae Chlorella vulgaris (C. vulgaris) on nonalcoholic fatty liver disease (NAFLD)-related complications induced by high-fat diet (HFD). Fifty adult male rats were divided into six groups. Control group and HFD group treated with or without C. vulgaris 5% and 10%. Biochemical parameters in serum were measured by spectrophotometric and enzyme-linked immunosorbent assay (ELISA) methods. The relative gene expression levels of Tumor Necrosis Factor-alpha (TNF-α), NF-kappa B (NF-ƙB), and p38 Mitogen-Activated Protein Kinases (p38 MAPK) in the liver were assessed by using quantitative real-time PCR, while the protein levels of NF-ƙB and TNF-α in the liver homogenate were determined by ELISA. The effects of HFD significantly were reversed by C. vulgaris, especially at a 10% dose. Therefore, it can be concluded that C. vulgaris therapeutically could be useful to improve NAFLD and its complications. PRACTICAL APPLICATIONS: It is established that NAFLD is associated with the resistance to insulin, dyslipidemia, and inflammation. Accordingly, modulating of these conditions may be useful in the management of NAFLD. Our results showed the effectiveness of C. vulgaris against NAFLD-related complication through the alleviating insulin resistance, dyslipidemia and also down-regulation of inflammatory genes in p38 MAPK/TNF-α/NF-ƙB pathway. The results of our study may be useful for scientist to prepare an effective supplement from C. vulgaris to overcoming NAFLD-related complications.

Prevalence and factors associated with NAFLD detected by vibration controlled transient elastography among US adults: Results from NHANES 2017-2018

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is increasingly common in the adult population. In the United States, the overall burden of NAFLD is unknown due to challenges with population-level NAFLD detection. The purpose of this study was to estimate prevalence of NAFLD and significant NAFLD fibrosis and identify factors associated with them in the U.S.

METHODS

Data came from the 2017-2018 cycle of National Health and Nutrition Examination Survey. We defined NAFLD by controlled attenuation parameter (CAP) scores of ≥248 dB/m in absence of excessive alcohol use and viral hepatitis. We defined significant fibrosis as Vibration controlled transient elastography (VCTE) liver stiffness measurements (LSM) value ≥7.9 kPa. We calculated the adjusted odds ratio (OR) and 95% confidential intervals (CI) for associations with NAFLD and significant NAFLD fibrosis using multivariable logistic regression.

RESULTS

Overall, among 4,024 individuals aged ≥20 years included in the analysis, 56.7% had NAFLD by CAP. In comparison, when defined by elevated liver enzymes, NAFLD prevalence was 12.4%. The prevalence of significant NAFLD fibrosis by VCTE LSM was 14.5%. NAFLD prevalence increased with age, was higher among men than women and among Hispanics compared with non-Hispanic whites. Individuals who were obese, had metabolic syndrome (MetS) and type 2 diabetes were more likely to have NAFLD compared to those that who were not obese or without MetS/diabetes. Inadequate physical activity (OR = 1.57, 95% CI: 1.18-2.08) was also a factor associated with NAFLD. MetS, high waist circumstance, diabetes and hypertension were independently associated with significant NAFLD fibrosis.

CONCLUSIONS

NAFLD and significant NAFLD fibrosis are highly prevalent in U.S. general population.

Dynamics of Serum Retinol and Alpha-Tocopherol Levels According to Non-Alcoholic Fatty Liver Disease Status

The available data on the association between micronutrients in the blood and non-alcoholic fatty liver disease (NAFLD) are limited. To investigate the clinical implications of this relationship, we sought to identify the difference in the serum levels of vitamins A and E according to NAFLD status using data from the seventh Korea National Health and Nutrition Examination Survey. In this cross-sectional study of the Korean population, NAFLD and its severity were defined using prediction models. Differences in the prevalence and severity of NAFLD were analyzed according to serum retinol (vitamin A) and alpha (α)-tocopherol (vitamin E) levels. Serum levels of retinol and α-tocopherol were positively correlated with the prevalence of NAFLD. In most prediction models of the NAFLD subjects, serum retinol deficiency was significantly correlated with advanced fibrosis, while serum α-tocopherol levels did not differ between individuals with or without advanced fibrosis. Similar trends were also noted with cholesterol-adjusted levels of α-tocopherol. In summary, while circulating concentrations of retinol and α-tocopherol were positively associated with the presence of NAFLD, advanced liver fibrosis was only correlated with serum retinol levels. Our findings could provide insight into NAFLD patient care at a micronutrient level.

Serum lipocalin-2 is a potential biomarker for the clinical diagnosis of nonalcoholic steatohepatitis

Background/Aims

Nonalcoholic steatohepatitis (NASH) is a progressive form of nonalcoholic fatty liver disease (NAFLD) characterized by hepatic steatosis, inflammation, hepatocellular injury, and fibrosis. We aimed to investigate the usefulness of a key biomarker, lipocalin-2 (LCN2), for the detection of NASH progression.

Methods

A mouse NASH model was established using a high-fat diet and a high-sugar drinking water. Gene expression profile of the NASH model was analyzed using RNA sequencing. Moreover, 360 NAFLD patients (steatosis, 83; NASH, 277), 40 healthy individuals, and 87 patients with alcoholic fatty liver disease were recruited.

Results

Inflammatory infiltration, focal necrosis in the leaflets, steatosis, and fibrosis were documented in the mouse liver. In total, 504 genes were differentially expressed in the livers of NASH mice, and showed significant functional enrichment in the inflammation-related category. Upregulated liver LCN2 was found to be significantly interactive with various interleukins and toll-like receptors. Serum LCN2 levels were significantly increased in NAFLD patients. Serum LCN2 levels were correlated with steatosis, intralobular inflammation, semiquantitative fibrosis score, and nonalcoholic fatty liver disease activity score. The area under the curve of serum LCN2 was 0.987 with a specificity of 100% and a sensitivity of 93.5% for NASH diagnosis, and 0.977 with almost the same specificity and sensitivity for steatosis.

Conclusions

LCN2 might be involved in the transition from NAFL to NASH by mediating inflammation. Serum LCN2 levels might be a novel biomarker for the diagnosis of NASH.

Systemic Overexpression of GDF5 in Adipocytes but Not Hepatocytes Alleviates High-Fat Diet-Induced Nonalcoholic Fatty Liver in Mice

OBJECTIVE

Our recent study demonstrated that growth differentiation factor 5 (GDF5) could promote white adipose tissue thermogenesis and alleviate high-fat diet- (HFD-) induced obesity in fatty acid-binding protein 4- (Fabp4-) GDF5 transgenic mice (TG). Here, we further investigated the effects of systemic overexpression of the GDF5 gene in adipocytes HFD-induced nonalcoholic fatty liver disease (NAFLD).

METHODS

Fabp4-GDF5 TG mice were administered an HFD feeding. NAFLD-related indicators associated with lipid metabolism and inflammation were measured. A GDF5 lentiviral vector was constructed, and the LO2 NAFLD cell model was induced by FFA solution (oleic acid and palmitic acid). The alterations in liver function, liver lipid metabolism, and related inflammatory indicators were analyzed.

RESULTS

The liver weight was significantly reduced in the TG group, which was in accordance with the significantly downregulated expression of TNFα, MCP1, Aim2, and SREBP-1c and significantly upregulated expression of CPT-1α and ACOX2 in TG mouse livers. Compared to that of cells in the FAA-free control group, LO2 cells with in situ overexpression of GDF5 developed lipid droplets after FFA treatment; the levels of triglycerides, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were significantly increased in both the GDF5 lentivirus and control lentivirus groups compared with those of the FAA-free group. Additionally, the levels of FAS, SREBP-1, CPT-1α, and inflammation-associated genes, such as ASC and NLRC4, were unaltered despite GDF5 treatment.

CONCLUSION

Systemic overexpression of GDF5 in adipose tissue in vivo significantly reduced HFD-induced NAFLD liver damage in mice. The overexpression of GDF5 in hepatocytes failed to improve lipid accumulation and inflammation-related reactions induced by mixed fatty acids, suggesting that the protective effect of GDF5 in NAFLD was mainly due to the reduction in adipose tissue and improvements in metabolism. Hence, our study suggests that the management of NAFLD should be targeted to reduce the overall amount of body fat and improve metabolic status before the progression to nonalcoholic steatohepatitis occurs.

Performance of non-invasive fibrosis scores in non-alcoholic fatty liver disease with and without morbid obesity

BACKGROUND

Non-invasive scores, such as the non-alcoholic fatty liver disease (NAFLD) Fibrosis Score (NFS), are increasingly used for liver fibrosis assessment in patients with NAFLD. The aim of this study was to assess the applicability and reliability of non-invasive fibrosis scores in NAFLD patients with and without morbid obesity.

METHODS

Three hundred sixty-eight patients with biopsy-proven NAFLD identified between January 2012 and December 2015 were studied; 225 with morbid obesity (biopsy obtained during bariatric surgery) and 143 patients without (termed as "conventional").

RESULTS

Median age was 47 years, 57% were female. Median body mass index (BMI) was 42.9 kg/m² with significant differences between our conventional and morbidly obese patients (BMI 29.0 vs. 50.8 kg/m², p < 0.001). Overall, 42% displayed mild/moderate and 16% advanced liver fibrosis (stage III/IV). All tested scores were significantly linked to fibrosis stage (p < 0.001 for all). FIB-4 (AUROC 0.904), APRI (AUROC 0.848), and NFS (AUROC 0.750) were identified as potent predictors of advanced fibrosis, although NFS overestimated fibrosis stage in morbid obesity. Limiting BMI to a maximum of 40 kg/m² improved NFS' overall performance (AUROC 0.838). FIB-4 > 1.0 indicated high probability of advanced fibrosis (OR = 29.1). FIB-4 predicted advanced fibrosis independently from age, sex, BMI, and presence of morbid obesity.

CONCLUSIONS

Our data suggest that FIB-4 score is an accurate predictor of advanced fibrosis in NAFLD throughout all BMI stages. Without adjustment, NFS tends to overestimate fibrosis in morbidly obese NAFLD patients. This problem may be solved by implementation of an upper BMI limit (for NFS) or adjustment of diagnostic thresholds.

The Role of Elastography in Non-Alcoholic Fatty Liver Disease

The most common liver disease in developing countries is non-alcoholic fatty liver disease (NAFLD). This involves the abnormal accumulation of lipids in the liver, the pathogenesis of the disease being related to dyslipidemia, obesity, insulin resistance and type 2 diabetes. Most often, the diagnosis of NAFLD is incidental, when performing routine blood tests or when performing a transabdominal ultrasound. The NAFLD spectrum ranges from simple forms of hepatic steatosis to the most advanced form of the disease, steatohepatitis (NASH), which in evolution can cause inflammation, fibrosis, cirrhosis of the liver and even liver cancer. For the evaluation of the prognosis and the clinical evolution, the most important parameter to define is the degree of liver fibrosis. Currently, the gold standard remains the liver biopsy, the differentiation between NAFLD and NASH being made only on the basis of histological analysis. However, liver biopsy is an invasive procedure, with numerous risks such as bleeding, lesions of the other organs and complications related to anesthesia, which significantly reduces its widespread use. Moreover, the risk of a false negative result and the increased costs of the procedure further limits its use in current practice. For this reason, non-invasive methods of evaluating the degree of liver fibrosis have gained ground in recent years. Imaging techniques such as elastography have shown promising results in evaluating and staging NAFLD. The aim of this article is to review the current status of the non-invasive tests for the assessment of NAFLD with a focus on the ultrasound-based elastography techniques.

Association of vitamin D supplementation with serum leptin and metabolic parameters in Egyptian patients with non-alcoholic steatohepatitis: a prospective study

Background

Nonalcoholic steatohepatitis (NASH) is the progressive form of NAFLD, a common cause of liver disease, with increased chance of progression to liver fibrosis, cirrhosis, and hepatocellular carcinoma. Circulating leptin is increased in patients with NASH. It is an independent positive predictor of the severity of hepatic steatosis. Vitamin D is a lipophilic molecule essential to maintain calcium and phosphate balance. Moreover, it has antifibrotic, antiproliferative, and anti-inflammatory effects on the liver. Vitamin D deficiency is a worldwide condition and very common in patients with NASH. Low serum vitamin D has been shown to predispose to intrahepatic lipid accumulation leading to NAFLD. The aim of this study was to investigate the association of vitamin D supplementation with serum leptin and metabolic parameters in Egyptian patients with non-alcoholic steatohepatitis

Results

Patients with NASH group had statistically significant higher values of diastolic blood pressure (94.3 ± 11.9 mmHg, p < 0.0001), glycated hemoglobin (8.0 ± 2.4%, p < 0.0001), fasting blood sugar (165.6 ± 62.0 mg/dL, p < 0.0001), fasting insulin level (24.2 ± 3.0 μU/ml, p < 0.0001), homeostatic model assessment of insulin resistance (HOMA-IR) (1.8 ± 0.7, p < 0.0001), alanine transferase (ALT) (78.2 ± 36.7 U/L, p < 0.0001), aspartate transferase (AST) (108.6 ± 85.6 U/L, p < 0.0001), NAFLD fibrosis score (− 0.78 ± 0.9, p < 0.0001), total cholesterol (233.0 ± 40.9 mg/dL, p = 0.0011), low-density lipoprotein (117.5 ± 41.6 mg/dL, p = 0.0084), and triglycerides (229.7 ± 62.1 mg/dL, p < 0.0001) than the control group. Moreover, they had lower serum vitamin D level (15.6 ± 6.6 ng/ml, p = 0.0004) and higher serum leptin level (35.9 ± 28.4 ng/ml, p < 0.0001) than the control group. Following vitamin D supplementation, there was a statistically significant reduction in HbA1c (6.8 ± 1.3%, p = 0.0055), fasting blood sugar (136.1 ± 32.7 mg/dL, p = 0.0094), fasting insulin level (22.9 ± 1.8 μU/ml, p = 0.0236), HOMA-IR (1.4 ± 0.4, p = 0.0026), ALT (55.3 ± 21.3 U/L, p = 0.0010), AST (73.1 ± 54.2 U/L, p = 0.0297), and triglycerides (203.6 ± 49.8 mg/dL, p = 0.0415) in patients with NASH. There was a statistically significant increase in serum vitamin D level (33.0 ± 7.6 ng/ml, p < 0.0001) and decrease in serum leptin level (23.5 ± 12.9 ng/ml, p = 0.0140) after treatment.

Conclusions

Vitamin D supplementation in patients with NASH in a dose of 4000 IU/day for 12 weeks improves severity of hepatic inflammation, decreases insulin resistance, improves glycemic control, corrects dyslipidemia, and protects against lipotoxicity by inhibition of serum leptin.

Non-invasive predictors of prognosis of Asian patients with histopathologically-confirmed lean nonalcoholic fatty liver disease

BACKGROUND

The prognostic factors of morbidity and mortality in patients with lean NAFLD (body mass index < 25.0 kg/m2) are unknown.

METHODS

In this retrospective study, 446 Japanese patients with histopathologically-confirmed NAFLD (lean NAFLD, n = 170) were followed for liver events, cardiovascular events, type 2 diabetes mellitus, and non-liver malignancies. The median observation period was 4.6 years. We also investigated the predictors of severe fibrosis (stage 3-4) and mortality in lean NAFLD patients.

RESULTS

Glycolipid metabolic markers, liver function tests, NAFLD fibrosis score (NFS), and histological scoring were significantly lower in lean NAFLD patients than in non-lean NAFLD. The incidence of liver cancer was higher while that of T2DM was lower in lean NAFLD. Kaplan-Meier analysis showed no significant difference in overall survival between the lean and non-lean NAFLD. Multivariate analysis of data of lean NAFLD identified NFS ≥ - 1.455 as significant independent predictor of severe fibrosis, while history of liver cancer and NFS ≥ - 1.455 were predictors of overall survival.

CONCLUSIONS

Although patients with lean NAFLD have better histopathological and biochemical profile compared to patients with non-lean NAFLD, the prognosis is not different between the two groups. Lean NAFLD patients with NFS ≥ - 1.455 or history of liver cancer should be monitored carefully during follow-up.

Nonalcoholic fatty liver disease and alcohol-related liver disease: From clinical aspects to pathophysiological insights

Two major causes of steatohepatitis are alcohol and metabolic syndrome. Although the underlying causes of alcohol-related liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH) differ, there are certain similarities in terms of the mode of disease progression and underlying pathophysiological mechanisms. Further, excessive alcohol consumption is often seen in patients with metabolic syndrome, and alcoholic hepatitis exacerbation by comorbidity with metabolic syndrome is an emerging clinical problem. There are certain ethnic differences in the development of both NAFLD and ALD. Especially, Asian populations tend to be more susceptible to NAFLD, and genetic polymorphisms in patatin-like phospholipase domain-containing 3 (PNPLA3) play a key role in both NAFLD and ALD. From the viewpoint of pathophysiology, cellular stress responses, including autophagy and endoplasmic reticulum (ER) stress, are involved in the development of cellular injury in steatohepatitis. Further, gut-derived bacterial products and innate immune responses in the liver most likely play a profound role in the pathogenesis of both ALD and NASH. Though the recent progress in the treatment of viral hepatitis has reduced the prevalence of viral-related development of hepatocellular carcinoma (HCC), non-viral HCC is increasing. Alcohol and metabolic syndrome synergistically exacerbate progression of steatohepatitis, resulting in carcinogenesis. The gut-liver axis is a potential therapeutic and prophylactic target for steatohepatitis and subsequent carcinogenesis.

TERT Promoter Mutation in Serum Cell-Free DNA Is a Diagnostic Marker of Primary Hepatocellular Carcinoma in Patients with Nonalcoholic Fatty Liver Disease

INTRODUCTION

It remains unclear whether TERT promoter mutation (TERT C228T) in serum cell-free DNA (cfDNA) is useful for the diagnosis of hepatocellular carcinoma (HCC) in patients with nonalcoholic fatty liver disease (NAFLD).

METHODS

In this retrospective study, we analyzed the relationships between TERT C228T in serum cfDNA and levels of AFP and PIVKAII in 57 Japanese patients with histopathologically confirmed NAFLD background, consisting of 36 patients with HCC and 21 without HCC. We also examined the liver-related survival rate and HCC recurrence rate after the initial treatment for HCC. TERT C228T was detected using a highly sensitive method based on wild-type blocking PCR (detection limit in excess of 0.7% mutant-type DNA).

RESULTS

In all of the 57 patients, multivariate analysis identified TERT C228T positive as significant determinant of primary HCC. In the 36 patients with HCC, the percentage of patients positive for TERT C228T was 63.9%. The percentage of patients positive for TERT C228T with normal AFP and PIVKAII was 35.3%. The positive predictive value and specificity for prediction of BCLC stage 0 or A were both high. In 6 patients, TERT C228T was repeatedly negative during follow-up but became positive at the time of HCC diagnosis. Four patients who underwent HCC surgical resection had well-differentiated solitary HCC measuring <30 mm, and all were TERT C228T positive with normal AFP and PIVKAII. TERT C228T status had no influence on the cumulative liver-related survival rate and HCC recurrence rate.

CONCLUSIONS

Our results highlight the superiority of TERT C228T in serum cfDNA compared with AFP and PIVKAII in the early diagnosis of primary HCC in NAFLD patients.

Nonalcoholic Fatty Liver Disease Is an Independent Risk Factor for Nephrolithiasis in Women: Findings from NHANES III

Objective: To determine if radiologically diagnosed nonalcoholic fatty liver disease (NAFLD) is an independent risk factor for nephrolithiasis using data from National Health and Nutrition Examination Survey III (NHANES III). Patients and Methods: NHANES III participants aged 20-74 years who underwent hepatobiliary ultrasound were classified as with NAFLD (moderate or severe hepatic steatosis in absence of other known causes of liver disease; n = 2498) or without NAFLD (controls; n = 9361). Risk of nephrolithiasis caused by NAFLD was estimated using logistic regression with propensity score adjustment. Secondary outcomes included medical stone management, lithotripsy, and surgical stone removal. Results: Participants with NAFLD were older (48.7 ± 0.4 vs 43.3 ± 0.3 years, p < 0.001) and exhibited greater prevalence of all components of metabolic syndrome: obesity (48% vs 21%), impaired glucose tolerance (17% vs 11%), diabetes mellitus (15% vs 6%), hypertension (36% vs 24%), and gout (4% vs 2%) (all p < 0.001). After adjusting for demographic, lifestyle, and metabolic factors, NAFLD was associated with increased risk nephrolithiasis (odds ratio [OR] = 1.29, 95% confidence interval [CI] [1.02-1.61], p = 0.03). The association persisted in women (OR = 1.65, 95% CI [1.17-2.32], p = 0.004) but not in men (OR = 1.04, 95% CI [0.77-1.40], p = 0.80). NAFLD was not associated with increased occurrence of medical management (OR = 1.31, 95% CI [0.84-2.05], p = 0.24), lithotripsy (OR = 1.61, 95% CI [0.83-3.33], p = 0.20), or surgical stone removal (OR = 0.83, 95% CI [0.48-1.44], p = 0.52). Conclusions: In a large U.S. population-based cross-sectional analysis, NAFLD was found to be associated with increased risk of nephrolithiasis in women after adjusting for demographic, clinical, and metabolic factors.

CCN1 promotes hepatic steatosis and inflammation in non-alcoholic steatohepatitis

Non-alcoholic fatty liver disease (NAFLD) is characterized by increased uptake and accumulation of lipids in hepatocytes. Simple steatosis may progress to non-alcoholic steatohepatitis (NASH) with inflammation, hepatocellular injury and fibrosis. CCN1 is an important matrix protein that regulates cell death and promotes immune cell adhesion and may potentially control this process. The role of CCN1 in NASH remains unclear. We investigated the role of CCN1 in the pathogenesis of steatohepatitis. CCN1 upregulation was found to be closely related with steatosis in patients with NASH, obese mice and a FFA-treated hepatocyte model. Controlling the expression of CCN1 in murine NASH models demonstrated that CCN1 increased the severity of steatosis and inflammation. From the sequence results, we found that fatty acid metabolism genes were primarily involved in the MCD mice overexpressing CCN1 compared to the control. Then, the expression of fatty acid metabolism genes was determined using a custom-designed pathway-focused qPCR-based gene expression array. Expression analysis showed that CCN1 overexpression significantly upregulated the expression of fatty acid metabolism-associated genes. In vitro analysis revealed that CCN1 increased the intracellular TG content, the pro-inflammatory cytokines and the expression level of apoptosis-associated proteins in a steatosis model using murine primary hepatocytes. We identified CCN1 as an important positive regulator in NASH.

Drug-Induced Steatosis and Steatohepatitis: The Search for Novel Serum Biomarkers Among Potential Biomarkers for Non-Alcoholic Fatty Liver Disease and Non-Alcoholic Steatohepatitis

Drug-induced steatosis (DIS) and drug-induced steatohepatitis (DISH) are two of several types of drug-induced liver injury (DILI). They can be caused by various drugs and may present as acute, potentially lethal disorders or as chronic slowly progressive liver injury. Despite the fact that they are distinct disorders, the slow progressive forms of DIS and DISH are often confused with or misdiagnosed as non-alcoholic fatty liver disease (NAFLD) or non-alcoholic steatohepatitis (NASH), which are much more common and, by definition, not caused by drugs. Currently the only way to identify DIS is via imaging studies or a liver biopsy, while DISH can be identified only through liver biopsy. In addition, diagnosis of either DIS or DISH requires an exhaustive clinical evaluation and comprehensive causality assessment to rule out other possible causes and determine the association with the suspected drug. Furthermore, it is difficult, using existing methods, to monitor the progression of DIS and DISH and to determine the underlying mechanism. Therefore, there is a great unmet need for non-invasive biomarkers that will be able to identify the development of DIS or DISH during drug development and to monitor for progression or regression of the disorder during treatment or following drug discontinuation. Recent developments in the fields of NAFLD and NASH have introduced several novel biomarkers that show promise for the diagnosis, monitoring, and severity assessment of these common diseases. Given the significant overlap in possible underlying mechanisms and histological pattern between NAFLD/NASH and DIS/DISH, these postulated NAFLD and NASH biomarkers may have a potential application to DIS and DISH. This article reviews the existing medical literature and other publically available information pertaining to novel serum biomarkers for NAFLD and NASH, and explores the concurrent identification of these biomarkers for DIS and DISH.

CircularRNA as novel biomarkers in liver diseases

The liver is an essential organ that is primarily responsible for digestion and eliminating toxic substances from the body. After the industrial revolution, Western diet and lifestyle changes have increased the incidence of several liver diseases, including non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), liver cirrhosis, and hepatocellular carcinoma (HCC). NAFLD and NASH are mostly asymptomatic at early stages, and the disease progression from NAFLD to life-threatening HCC remains not fully understood. Circular RNA (circRNA) is consist of a circular structure, and the circRNA-microRNA(miRNA)-mRNA axes have been shown to be involved in several cellular events, including apoptosis, vascularization, metastasis, etc. The highly stable structure of circRNAs has enabled themselves to be used as putative biomarkers of several diseases. Here, we conducted a literature review and discussed the identified roles of circRNAs in NAFLD, NASH, liver cirrhosis, and HCC. For example, deficiency of circRNA_0046366 and circRNA_0046367 has been shown as the characteristics of NAFLD, and restoration of these circRNAs ameliorates the oxidative stress, lipotoxicity, and disease severity in NAFLD. Silencing of circ_0071410 was shown to alleviate hepatic stellate activation, the key step of liver cirrhosis. CDR1 and circ_0067934 can facilitate the invasion and metastasis of HCC, while circMTO1 negatively regulates the progression of HCC. Although several research works have been conducted, the whole picture of circRNA-related underlying mechanisms is unclear. Future works using high-throughput bioinformatic approaches will be needed to delineate the role of circRNAs in liver diseases and to further develop novel diagnostics and therapeutics.

Baicalein reduces hepatic fat accumulation by activating AMPK in oleic acid-induced HepG2 cells and high-fat diet-induced non-insulin-resistant mice

Nonalcoholic fatty liver disease (NAFLD) has become the most common liver disease worldwide; thus, a dietary supplement that can restrict hepatic fat accumulation is needed.

Mechanisms of liver fibrosis and its role in liver cancer

Hepatic fibrogenesis is a pathophysiological outcome of chronic liver injury hallmarked by excessive accumulation of extracellular matrix proteins. Fibrosis is a dynamic process that involves cross-talk between parenchymal cells (hepatocytes), hepatic stellate cells, sinusoidal endothelial cells and both resident and infiltrating immune cells. In this review, we focus on key cell-types that contribute to liver fibrosis, cytokines, and chemokines influencing this process and what it takes for fibrosis to regress. We discuss how mitochondria and metabolic changes in hepatic stellate cells modulate the fibrogenic process. We also briefly review how the presence of fibrosis affects development of hepatocellular carcinoma.

Circulating MicroRNA-122 and Fibrosis Stage Predict Mortality of Japanese Patients With Histopathologically Confirmed NAFLD

The impact of circulating microRNA‐122 (miR‐122) on mortality in patients with histopathologically confirmed nonalcoholic fatty liver disease (NAFLD) remains unclear. We analyzed the overall survival rates in 441 Japanese patients with histopathologically confirmed NAFLD after a median follow‐up period of 4.7 years. We also determined the clinicopathologic, genetic, and epigenetic parameters, including serum miR‐122 levels, for prediction of mortality. Of the 441 study patients, 21 (4.8%) died during the follow‐up period. The cumulative survival rates were 95.4% and 90.6% at the end of 5 and 10 years, respectively. Multivariate analysis identified history of liver cancer (presence; hazard ratio [HR], 4.94; 95% confidence interval [CI], 1.84‐13.3), serum miR‐122 (<1.00 fold change; HR, 4.35; 95% CI, 0.06‐0.83), and fibrosis‐4 index (FIB‐4 index) (≥1.30; HR, 15.7; 95% CI, 2.01‐122) as significant risk factors of mortality. Cumulative survival rates varied significantly among patients with none/one risk factor, two risk factors, and three risk factors; particularly, the survival rate of patients with three risk factors was significantly lower than those with two risk factors and none/one risk factor. Two or more risk factors were identified in 17 of 21 (81.0%) death cases. Conclusion: The importance of serum miR‐122 and FIB‐4 index as risk factors for mortality in Japanese patients with histopathologically confirmed NAFLD is shown. Early diagnosis based on the presence of more than one risk factor and early treatment might improve the prognosis.

Low vitamin D level was associated with metabolic syndrome and high leptin level in subjects with nonalcoholic fatty liver disease: a community-based study

Background

This study aimed to evaluate the association between serum vitamin D levels and nonalcoholic fatty liver disease (NAFLD) parameters, such as metabolic syndrome (MS), inflammatory cytokines (tumor necrosis factor, high sensitive C-reactive protein) and adipokines (adiponectin, leptin).

Methods

From August 2013 to August 2016, a community-based study was performed in the north-eastern region of Taiwan. All subjects received a demographic survey, blood testing and abdominal ultrasonography (US). The vitamin D level was evaluated by quartile divide or used the classification of deficiency (< 20 ng/ml), insufficiency (20–30 ng/ml) and sufficiency (> 30 ng/ml).

Results

Subjects were divided into NAFLD group and normal control (subjects number = 564 in each group) following abdominal US study and matching age and gender. The mean age was 57.1 years in NAFLD group and 57.5 in control group. Subjects in NAFLD group had a lower mean vitamin D than those in the control group (28.5 ± 9.5 ng/ml vs. 29.9 ± 10.2 ng/ml, P = 0.018). Subjects with serum vitamin D deficiency or insufficiency had higher odds for MS than those with sufficient vitamin D levels [deficiency vs. sufficiency, adjusted odds ratio (aOR) =1.860 (95% CI = 1.234–2.804), P = 0.003; insufficiency vs. sufficiency, aOR = 1.669 (95% CI = 1.237–2.251), P = 0.001]. Similarly, subjects in the lowest quartile of vitamin D had higher odds for MS than those in the highest quartile of vitamin D (aOR = 2.792, 95% CI = 1.719–4.538, P < 0.001). Vitamin D level was positively correlated with age and male, but negatively correlated with serum leptin level.

Conclusion

Subjects with low vitamin D level had higher odds for MS, but higher levels of leptin, compared to those with high vitamin D levels.

Dual-Specificity Phosphatase 26 Protects Against Nonalcoholic Fatty Liver Disease in Mice Through Transforming Growth Factor Beta-Activated Kinase 1 Suppression

Nonalcoholic fatty liver disease (NAFLD), which has a wide global distribution, includes different stages ranging from simple steatosis to nonalcoholic steatohepatitis, advanced fibrosis, and liver cirrhosis according to the degree of severity. Chronic low-grade inflammation, insulin resistance, and lipid accumulation are the leading causes of NAFLD. To date, no effective medicine for NAFLD has been approved by governmental agencies. Our study demonstrated that the expression of dual-specificity phosphatase 26 (Dusp26), a member of the Dusp protein family, was decreased in the liver tissue of mice with hepatic steatosis and genetically obese (ob/ob) mice. In our study, hepatic steatosis, inflammatory responses, and insulin resistance were exacerbated in liver-specific Dusp26-knockout (KO) mice but ameliorated in liver-specific Dusp26-transgenic mice induced by a high-fat diet. In addition, the degree of liver fibrosis was aggravated in high-fat high-cholesterol diet-induced Dusp26-KO mice. We further found that the binding of Dusp26 to transforming growth factor beta-activated kinase 1 (TAK1) to block the phosphorylation of TAK1 regulated the TAK1-p38/c-Jun NH2-terminal kinase signaling axis to alleviate hepatic steatosis and metabolic disturbance. Conclusion: These findings suggest that Dusp26 is a good TAK1-dependent therapeutic target for NAFLD.

Hepatic steatosis and reduction in steatosis following bariatric weight loss surgery differs between segments and lobes

OBJECTIVES

The purpose of this study was to (1) evaluate proton density fat fraction (PDFF) distribution across liver segments at baseline and (2) compare longitudinal segmental PDFF changes across time points in adult patients undergoing a very low-calorie diet (VLCD) and subsequent bariatric weight loss surgery (WLS).

METHODS

We performed a secondary analysis of data from 118 morbidly obese adult patients enrolled in a VLCD-WLS program. PDFF was estimated using magnitude-based confounder-corrected chemical-shift-encoded (CSE) MRI in each hepatic segment and lobe at baseline (visit 1), after completion of VLCD (visit 2), and at 1, 3, and 6 months (visits 3-5) following WLS. Linear regressions were used to estimate the rate of PDFF change across visits. Lobar and segmental rates of change were compared pairwise.

RESULTS

Baseline PDFF was significantly higher in the right lobe compared to the left lobe (p < 0.0001). Lobar and segmental PDFF declined by 3.9-4.5% per month between visits 1 and 2 (preoperative period) and by 4.3-4.8% per month between visits 1 and 3 (perioperative period), but no significant pairwise differences were found in slope between segments and lobes. For visits 3-5 (postoperative period), lobar and segmental PDFF reduction was much less overall (0.4-0.8% PDFF per month) and several pairwise differences were significant; in each case, a right-lobe segment had greater decline than a left-lobe segment.

CONCLUSIONS

Baseline and longitudinal changes in fractional fat content in the 5-month postoperative period following WLS vary across segments, with right-lobe segments having higher PDFF at baseline and more rapid reduction in liver fat content.

KEY POINTS

• Baseline and longitudinal changes in liver fat following bariatric weight loss surgery vary across liver segments. • Methods that do not provide whole liver fat assessment, such as liver biopsy, may be unreliable in monitoring longitudinal changes in liver fat following weight loss interventions.

Pathophysiological, Molecular and Therapeutic Issues of Nonalcoholic Fatty Liver Disease: An Overview

Nonalcoholic Fatty Liver Disease (NAFLD) represents the leading cause of liver disease in developed countries but its diffusion is currently also emerging in Asian countries, in South America and in other developing countries. It is progressively becoming one of the main diseases responsible for hepatic insufficiency, hepatocarcinoma and the need for orthotopic liver transplantation. NAFLD is linked with metabolic syndrome in a close and bidirectional relationship. To date, NAFLD is a diagnosis of exclusion, and liver biopsy is the gold standard for diagnosis. NAFLD pathogenesis is complex and multifactorial, mainly involving genetic, metabolic and environmental factors. New concepts are constantly arising in the literature promising new diagnostic and therapeutic tools. One of the challenges will be to better characterize not only NAFLD development but overall NAFLD progression, in order to better identify NAFLD patients at higher risk of metabolic, cardiovascular and neoplastic complications. This review analyses NAFLD epidemiology and the different prevalence of the disease in distinct groups, particularly according to sex, age, body mass index, type 2 diabetes and dyslipidemia. Furthermore, the work expands on the pathophysiology of NAFLD, examining multiple-hit pathogenesis and the role of different factors in hepatic steatosis development and progression: genetics, metabolic factors and insulin resistance, diet, adipose tissue, gut microbiota, iron deposits, bile acids and circadian clock. In conclusion, the current available therapies for NAFLD will be discussed.

Recent research trends and updates on nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD), together with metabolic syndrome and obesity, has shown a rapid increase in prevalence worldwide and is emerging as a major cause of chronic liver disease and liver transplantation. Among the various phenotypes of NAFLD, nonalcoholic steatohepatitis (NASH) is highly likely to progress to development of end-stage liver disease and cardiometabolic disease, resulting in liver-related and non-liver-related mortality. Nonetheless, there is no standardized pharmacotherapy against NASH and many drugs are under development in ongoing clinical trials. To develop a successful anti-NASH drug, it is necessary to select an appropriate target population and treatment outcomes depending on whether the mode of action is anti-metabolic, anti-inflammatory or anti-fibrotic. Recently, innovative surrogate markers have been investigated to replace hard outcomes such as liver histology and mortality and reduce the clinical trial duration. Currently, several drugs with fast track designation are being tested in phase III clinical trials, and many other drugs have moved into phase II clinical trials. Both lean NAFLD and typical obese NAFLD have been extensively studied and genetic variants such as PNPLA3 and TM6SF2 have been identified as significant risk factors for lean NAFLD. In the near future, noninvasive biomarkers and effective targeted therapies for NASH and associated fibrosis are required to develop precision medicine and tailored therapy according to various phenotypes of NAFLD.

Accuracy of non-invasive scoring systems for diagnosing non-alcoholic steatohepatitis-related fibrosis: Multicenter validation study

AIM

Hepatic fibrosis is the most important factor for estimating the prognosis of patients with non-alcoholic fatty liver disease (NAFLD). A novel non-invasive scoring system, the FM-fibro index, showed high accuracy in a pilot study. The purpose of this study was to validate the efficacy of the FM-fibro index in a multicenter cohort.

METHODS

Among 18 institutions, we analyzed 400 Japanese patients with biopsy-proven NAFLD. We evaluated the accuracies of the FM-fibro index, CA-fibro index, and European Liver Fibrosis (ELF) panel by area under the receiver operator characteristics curves (AUROC). The FM-fibro index includes three formulas for type IV collagen 7S, hyaluronic acid, and vascular cell adhesion molecule-1.

RESULTS

Among 400 patients, 205 were women, and the median age was 56 years. The histological distribution of Matteoni types 1, 2, 3, and 4 was 11, 40, 15, and 334, and the distribution of hepatic fibrosis stages 0 to 4 was 67, 183, 55, 63, and 32, respectively. The AUROCs of the FM-fibro index, CA-fibro index, and ELF panel for non-alcoholic steatohepatitis (NASH)-related fibrosis were 0.7178/0.7095/0.7065, 0.7093, and 0.7245, respectively. The sensitivity and specificity of the FM-fibro index for predicting NASH-related fibrosis was 0.5359/0.5210/0.4641 and 0.8333/0.8182/0.8788, respectively. The accuracy of the FM-fibro index was not significantly different from that of the CA-fibro index or the ELF panel.

CONCLUSIONS

The FM-fibro index can predict NASH-related fibrosis with sufficient accuracy compared with previous scoring systems. Further analyses that verify the accuracy of the FM-fibro index to distinguish significant or advanced fibrosis in patients with NAFLD are awaited. (UMIN-CTR: UMIN000018158).

Hepatocellular carcinoma is the most common liver-related complication in patients with histopathologically-confirmed NAFLD in Japan

BACKGROUND

The incidence of liver-related events, cardiovascular events and type 2 diabetes mellitus in patients with histopathologically confirmed NAFLD remains unclear.

METHODS

We retrospectively investigated the incidence of liver events, cardiovascular events, malignancy, and type 2 diabetes mellitus in 402 Japanese patients with histopathologically confirmed NAFLD for a median follow-up of 4.2 years. We also investigated predictors of the development of hepatocellular carcinoma and type 2 diabetes mellitus in these patients.

RESULTS

The rate of liver-related events per 1000 person years was 4.17 (hepatocellular carcinoma, 3.67; hepatic encephalopathy, 1.60; esophago-gastric varices, 2.43; ascites, 0.80; and jaundice, 0.40). The rate of cardiovascular events and type 2 diabetes mellitus was 5.73 and 9.95, respectively. Overall mortality was 3.33 (liver-related events, 1.25; cardiovascular events, 0.42; and malignancies other than hepatocellular carcinoma, 0.83), in patients free of previous or current malignancies. Multivariate analyses identified old age (≥70 years) and advanced fibrosis stage 4 as significant determinants of hepatocellular carcinoma development, and hepatocyte steatosis (> 33%), female sex, and serum ferritin (≤80 μg/l) as significant determinants of type 2 diabetes mellitus development in these patients.

CONCLUSIONS

Our results highlighted the importance of cardiovascular and liver-related events in Japanese patients with histopathologically-confirmed NAFLD. Hepatocellular carcinoma was the most common liver-related event, and the incidence of hepatocellular carcinoma was more than half of that of cardiovascular events.

Male-specific association between subclinical hypothyroidism and the risk of non-alcoholic fatty liver disease estimated by hepatic steatosis index: Korea National Health and Nutrition Examination Survey 2013 to 2015

Non-alcoholic fatty liver disease (NAFLD) is a prevalent liver disease encompassing a broad spectrum of pathologic changes in the liver. Metabolic derangements are suggested to be main causes of NAFLD. As thyroid hormone is a main regulator of energy metabolism, there may be a link between NAFLD and thyroid function. In previous studies, the association between NAFLD and thyroid function was not conclusive. The aim of this study was to clarify the relationship between NAFLD and thyroid function, focusing on subclinical hypothyroidism, using nationwide survey data representing the Korean population. NAFLD was defined as a hepatic steatosis index of 36 or higher. Based on the analysis of nationwide representative data, subclinical hypothyroidism was related to a high risk of NAFLD in males, but not in females. Our study showed that thyroid function might play a substantial role in the development of NAFLD, especially in males. Further study to elucidate the underlying mechanism of gender specific association of mild thyroid dysfunction and NAFLD would be required.

Nonalcoholic fatty liver disease: current concepts, epidemiology and management strategies

Nonalcoholic fatty liver disease (NAFLD) is now the most prevalent liver disease in the world. It involves a spectrum of conditions from hepatic steatosis to nonalcoholic steatohepatitis and liver fibrosis, and is a major cause of cirrhosis and hepatocellular carcinoma. It is defined by presence of steatosis in 5% of hepatocytes or more in the absence of other causes of fatty liver. The metabolic syndrome is the major known risk factor for NAFLD. Dietary contributors such as high fructose intake and coffee consumption appear to increase and decrease the risk of disease respectively, but these links are unclear. Genetic associations have also been identified. The estimated prevalence of the disease varies according to diagnostic method and population demographics. It appears to be a major issue in Europe with population studies showing up to 50% of the individuals are affected while in the USA one in three adults are estimated to have NAFLD. Laboratory investigations and ultrasound are typically first-line investigations. Fibrosis may be assessed noninvasively through transient elastography and biomarkers but liver biopsy remains the gold standard to quantify hepatic damage. Associated comorbidities include cardiovascular disease and chronic kidney disease. Weight loss, dietary changes and exercise are recommended in management. Medications should be considered to manage underlying risk factors including insulin resistance. Surgical options include bariatric procedures and liver transplantation. The combination of rising prevalence and significant potential complications warrant further research into NAFLD, particularly in areas with research gaps including Eastern Europe.

A systematic review of the present and future of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the Western world. Ongoing research has furthered our understanding of NAFLD, the nature of progression of this disease, and its impact on morbidity and mortality. An active form of NAFLD is non-alcoholic steatohepatitis (NASH); it is the most severe subtype, without any current recommended therapies, according to the European Medicines Agency. The development of new therapies presents challenges, notably due to the slow progression of NASH and the clinically relevant endpoints.

Correlating new data with effective treatment regimens is an emerging challenge, which will increase our understanding of the factors affecting the NAFLD course. This can enable more appropriate non-invasive prognostic assessments, which can focus on specifically at-risk NAFLD populations for tailored individual treatment. This review article aims to highlight the current developments in the field of NAFLD: pathogenesis, epidemiology, diagnosis, clinical features, and available treatment, including novel targets and therapies.

Prostaglandin I2 suppresses the development of diet-induced nonalcoholic steatohepatitis in mice

Nonalcoholic steatohepatitis (NASH) is a hepatic manifestation of metabolic syndrome. Although the prostaglandin (PG)I₂ receptor IP is expressed broadly in the liver, the role of PGI₂-IP signaling in the development of NASH remains to be determined. Here, we investigated the role of the PGI₂-IP system in the development of steatohepatitis using mice lacking the PGI₂ receptor IP [IP-knockout (IP-KO) mice] and beraprost (BPS), a specific IP agonist. IP-KO and wild-type (WT) mice were fed a methionine- and choline-deficient diet (MCDD) for 2, 5, or 10 wk. BPS was administered orally to mice every day during the experimental periods. The effect of BPS on the expression of chemokine and inflammatory cytokines was examined also in cultured Kupffer cells. WT mice fed MCDD developed steatohepatitis at 10 wk. IP-KO mice developed steatohepatitis at 5 wk with augmented histologic derangements accompanied by increased hepatic monocyte chemoattractant protein-1 (MCP-1) and TNF-α concentrations. After 10 wk of MCDD, IP-KO mice had greater hepatic iron deposition with prominent oxidative stress, resulting in hepatocyte damage. In WT mice, BPS improved histologic and biochemical parameters of steatohepatitis, accompanied by reduced hepatic concentration of MCP-1 and TNF-α. Accordingly, BPS suppressed the LPS-stimulated Mcp-1 and Tnf-α mRNA expression in cultured Kupffer cells prepared from WT mice. PGI₂-IP signaling plays a crucial role in the development and progression of steatohepatitis by modulating the inflammatory response, leading to augmented oxidative stress. We suggest that the PGI₂-IP system is an attractive therapeutic target for treating patients with NASH.-Kumei, S., Yuhki, K.-I., Kojima, F., Kashiwagi, H., Imamichi, Y., Okumura, T., Narumiya, S., Ushikubi, F. Prostaglandin I₂ suppresses the development of diet-induced nonalcoholic steatohepatitis in mice.