Review article: new treatments in non-alcoholic fatty liver disease

Phosphorylation: new star of pathogenesis and treatment in steatotic liver disease

Steatotic liver disease poses a serious threat to human health and has emerged as one of the most significant burdens of chronic liver disease worldwide. Currently, the research mechanism is not clear, and there is no specific targeted drug for direct treatment. Phosphorylation is widely regarded as the most common type of protein modification, closely linked to steatotic liver disease in previous studies. However, there is no systematic review to clarify the relationship and investigate from the perspective of phosphorylation. Phosphorylation has been found to mainly regulate molecule stability, affect localization, transform molecular function, and cooperate with other protein modifications. Among them, adenosine 5'-monophosphate-activated protein kinase (AMPK), serine/threonine kinase (AKT), and nuclear factor kappa-B (NF-kB) are considered the core mechanisms in steatotic liver disease. As to treatment, lifestyle changes, prescription drugs, and herbal ingredients can alleviate symptoms by influencing phosphorylation. It demonstrates the significant role of phosphorylation as a mechanism occurrence and a therapeutic target in steatotic liver disease, which could be a new star for future exploration.

Effects of silymarin use on liver enzymes and metabolic factors in metabolic dysfunction-associated steatotic liver disease: a systematic review and meta-analysis

Background

Fatty liver disease comprises a wide range of related liver disorders affecting mainly people who drink no or minimal amounts of alcohol. Silymarin is a member of the Carduus marianum family that has been used for centuries to treat different diseases. There is little evidence supporting its efficacy in humans.

Objectives

To evaluate the effects of Silymarin in patients with non alcoholic fatty liver disease (NAFLD) or recently renamed metabolic dysfunction-associated steatotic liver disease (MASLD).

Methods

We searched PubMed, SCOPUS, Web of Science, and Cochrane Library for relevant clinical trials assessing the use of silymarin in patients with NAFLD. A risk of bias assessment was performed using Cochrane's risk of bias tool. We included the following outcomes: alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyl transferase (GGT), total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL) (mg/dL), degree of fibrosis resolution, low-density lipoprotein (LDL), and HOMA-IR. We analyzed continuous data using mean difference (MD) and relative 95% confidence interval (CI).

Results

We included nine clinical trials. We found that silymarin significantly reduced the levels of ALT (MD= -17.12 [-28.81, -4.43]), (P < 0.004), AST (MD= -12.56 [-19.02, -6.10]), (P < 0.0001) and TG (MD = -22.60 [-23.83, -21.38]) (p < 0.00001). It also improved HDL (MD= 2.13 [1.60, 2.66]), (P < 0.01)). There was no significant difference regarding GGT (P=o.07), TC (P= 0.52), LDL (P= 0.06), HOMA-IR (P= 0.06) and BMI (p=0.1).One study reported significant improvement in the degree of fibrosis (P = 0.023).

Conclusion

Silymarin treatment significantly reduces biochemical and transaminase levels in patients with MASLD.

Inflammatory signaling in NASH driven by hepatocyte mitochondrial dysfunctions

Liver steatosis, inflammation, and variable degrees of fibrosis are the pathological manifestations of nonalcoholic steatohepatitis (NASH), an aggressive presentation of the most prevalent chronic liver disease in the Western world known as nonalcoholic fatty liver (NAFL). Mitochondrial hepatocyte dysfunction is a primary event that triggers inflammation, affecting Kupffer and hepatic stellate cell behaviour. Here, we consider the role of impaired mitochondrial function caused by lipotoxicity during oxidative stress in hepatocytes. Dysfunction in oxidative phosphorylation and mitochondrial ROS production cause the release of damage-associated molecular patterns from dying hepatocytes, leading to activation of innate immunity and trans-differentiation of hepatic stellate cells, thereby driving fibrosis in NASH.

Non-alcoholic Steatohepatitis: From Pathophysiology to Clinical Practice

Non-alcoholic steatohepatitis (NASH) is becoming a global disease with significant associated comorbidities. To date, there are no commercialized drugs to treat NASH, outside of India; however, there is an abundance of new molecular entities which are in clinical development, some in phase III trials. Many of these trials have created an especially heavy demand for USA-based subjects. Hepatologists currently play a major role in the diagnosis, treatment and clinical-trial enrolment of patients with NASH. However, NASH has a strong metabolic component, with patients often carrying comorbid diseases, such as type 2 diabetes mellitus, obesity, hyperlipidaemia, hypothyroidism and sex steroid disorders. The primary care physician, internist and endocrinologist stand at a pivotal position in the NASH healthcare delivery system, as many of the diseases they commonly encounter are associated with a higher risk of developing NASH. Specialty society practice guidelines are evolving regarding the identification and care of patients with NASH. This review of the literature, and assessment of IQVIA's proprietary patient claims database of diagnosis codes, patient encounters and treatments, substantiates the importance of the primary care provider and endocrinologist in the clinical care and clinical research of patients with NASH.

Integrated Transcriptomic and Translatomic Inquiry of the Role of Betaine on Lipid Metabolic Dysregulation Induced by a High-Fat Diet

An excessive high-fat/energy diet is a major cause of obesity and linked complications, such as non-alcoholic fatty liver disease (NAFLD). Betaine has been shown to effectively improve hepatic lipid metabolism. However, the mechanistic basis for this improvement is largely unknown. Herein, integration of mRNA sequencing and ribosome footprints profiling (Ribo-seq) was used to investigate the means by which betaine alleviates liver lipid metabolic disorders induced by a high-fat diet. For the transcriptome, gene set enrichment analysis demonstrated betaine to reduce liver steatosis by up-regulation of fatty acid beta oxidation, lipid oxidation, and fatty acid catabolic processes. For the translatome, 574 differentially expressed genes were identified, 17 of which were associated with the NAFLD pathway. By combined analysis of transcriptome and translatome, we found that betaine had the greater effect on NAFLD at the translational level. Further, betaine decreased translational efficiency (TE) for IDI1, CYP51A1, TM7SF2, and APOA4, which are related to lipid biosynthesis. In summary, this study demonstrated betaine alleviating lipid metabolic dysfunction at the translational level. The transcriptome and translatome data integration approach used herein provides for a new understanding of the means by which to treat NAFLD.

Network pharmacology-based investigation to explore the effect and mechanism of Erchen decoction against the nonalcoholic fatty liver disease

This study aimed to uncover the potential mechanism of Erchen decoction (ECD) on the amelioration of nonalcoholic fatty liver disease (NAFLD). Network pharmacology and bioinformatics were used to determine the active components of ECD and its potential target in treating NAFLD. High fat diet (HFD)-induced NAFLD mice model was used. Liver tissues were stained with hematoxylin and eosin, and Oil Red O. Serum lipid profiles and hepatic inflammatory molecules in lipopolysaccharide (LPS)/Toll-like receptor-4 (TLR-4) pathway were confirmed by enzyme-linked immunosorbent assay. Intestinal barrier function, including intestinal epithelial tight junction (IETJ) proteins, fecal short-chain fatty acids (SCFAs) concentration and intestinal microbiota composition, was also assessed. Screening relevant databases revealed 123 active components and 158 potential target proteins in ECD, as well as 1,783 differential genes for NAFLD. Enrichment analyses predicted that the regulation of LPS, cholesterol metabolism and inflammatory pathways might be the underlying mechanisms of ECD in NAFLD treatment. ECD ameliorated the multi-profiles of NAFLD and reversed the high levels of inflammatory molecules such as, serum LPS, hepatic TLR-4, tumor necrosis factor-α, and interleukin-1β. Additionally, ECD upregulated the concentration levels of IETJ proteins and fecal SCFAs. 16s RNA sequencing indicated that ECD can improve the gut microbiota, such as Akkermansia, Clostridium XIVa, Coprococcus, and Ruminococcus. The current study demonstrated that ECD can reverse the HFD-induced intestinal barrier dysfunction, thereby reducing the LPS translocation and alleviating the hepatic inflammation, and eventually exhibiting a protective effect against NAFLD.

Administration of hydro-alcoholic extract of spinach improves oxidative stress and inflammation in high-fat diet-induced NAFLD rats

Background

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide. The aim of this study was to evaluate the effects of hydro-alcoholic extract of spinach (HES) on hepatic and serum measurements of NAFLD in a rat model.

Methods

In the prevention phase, 18 Sprague–Dawley rats were fed a high-fat diet, a high-fat diet plus 400 mg/kg HES, or a chow diet for seven weeks. For the treatment phase, after the induction of NAFLD, they were fed a high-fat diet, a high-fat diet plus 400 mg/kg HES, a chow diet, or a chow diet plus 400 mg/kg HES for four weeks (n = 6).

Results

Administration of HES combined with high-fat diet in rats was associated with decreased food intake (P < 0.01), weight loss (P = 0.01), and increased superoxide dismutase (SOD) (P = 0.02) enzyme activity in the liver, at the end of the prevention phase. hs-CRP (P < 0.05), PTX-3 (P < 0.05), and TNF-α (P < 0.05) gene expression in the liver were decreased and PPAR-γ (P < 0.05) gene expression in the liver was increased by spinach intake, both in the prevention and treatment phases. Furthermore, administration of spinach in the treatment phase increased serum TAC (P = 0.03) and hepatic GPX (P = 0.01) enzyme activity.

Conclusion

Taking into account the potential beneficial effects of HES on prevention and treatment of NAFLD in the present study, to confirm these findings, we propose that further clinical trials be conducted on human subjects with NAFLD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-021-03396-x.

Effects of sodium-glucose co-transporter 2 inhibitors on liver parameters and steatosis: A meta-analysis of randomized clinical trials

AIMS

Non-alcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease in Western countries and a common comorbidity with type 2 diabetes (T2D). It lacks effective pharmacotherapy. We aimed to summarize the evidence on the effects of sodium-glucose co-transporter 2 (SGLT2) inhibitors on liver structure and function.

MATERIALS AND METHODS

Meta-analysis of randomized clinical trials in PubMed, Web of Science and ClinicalTrials.gov from their inception to April 2019. Trials evaluating liver function and/or structure and comparing SGLT2 inhibitors with placebo or other oral antidiabetic drugs in patients with T2D were included. Twenty studies (from 3033) were included. A total of 1950 patients with T2D, with or without NAFLD, were treated with SGLT2 inhibitors for at least 8 weeks, and 1900 patients were used as controls. Independent extraction was carried out by two observers. This study was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis.

RESULTS

SGLT2 inhibitors induced a significant decrease in serum alanine (-7.43U/L, [95%CI -12.14, -2.71], p < 0.01), in aspartate aminotransferases (-2.83U/L, [-4.71, -0.95], p < 0.01), as well as in gamma glutamyl transferase (-8.21U/L, [-9.52, -6.91], p < 0.01), and an increase in total plasma bilirubin (8.19% [0.79, 15.59], p < 0.01), comparing with placebo or other oral antidiabetic drugs. SGLT2 inhibitors treatment was associated with a decrease in liver steatosis (-3.39% [-6.01, -0.77], p < 0.0.1).

CONCLUSIONS

Treatment with SGLT2 inhibitors improves liver structure and function in patients with T2D. This meta-analysis suggests that SGLT2 inhibitors are a promising pharmacological approach for treatment of NAFLD.

Integrative transcriptomics and metabolomics explore the mechanism of kaempferol on improving nonalcoholic steatohepatitis

Kaempferol has been confirmed to be effective in improving metabolic diseases such as diabetes and obesity. However, its effect and mechanism in nonalcoholic steatohepatitis (NASH) are unclear. We aim to confirm whether kaempferol could improve NASH and find the corresponding differential genes and metabolites. Transcriptomics combined with metabolomics was used to investigate the alterations in genes and metabolites expression after kaempferol treatment in mice with high-fat-diet-induced NASH. The results showed that kaempferol reduced the level of alanine transaminase (ALT), low-density lipoprotein cholesterol (LDL-C), and total cholesterol (TC) in serum and triglyceride (TG), lipid droplets, and inflammatory cell infiltration in liver. Further, 277 differentially expressed genes (DEGs) were identified through liver transcriptomics and the five most obvious DEGs were found to be CYP2b9, Cyp4a12b, Mup17, Mup7, and Mup16, which revealed that HFD induced fatty acid degradation, ribosome, and glyoxylic acid and dicarboxylic acid metabolism. Nine serum metabolites (methylcysteine, l-tryptophan, adrenic acid, d-2-hydroxyglutaric acid, tartaric acid, p-cresol sulfate, l-alanine, l-tryosine, and glutaconic acid) and 3 liver differential metabolites (gallic acid, γ-lindenic acid, and l-phenylalanine) were also identified, while the pathways were mainly involved in phenylalanine, tyrosine, and tryptophan biosynthesis; and phenylalanine metabolism. Integrating transcriptomics and metabolomics analyses indicated that kaempferol possesses the ability to improve NASH associated with energy metabolism, lipid metabolism, oxidative stress, and inflammation-related pathways. This study provides a powerful means of multiomics data integration and reveals the potent therapy and biomarkers for kaempferol.

Non-coding RNA crosstalk with nuclear receptors in liver disease

The dysregulation of nuclear receptors (NRs) underlies the pathogenesis of a variety of liver disorders. Non-coding RNAs (ncRNAs) are defined as RNA molecules transcribed from DNA but not translated into proteins. MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are two types of ncRNAs that have been extensively studied for regulating gene expression during diverse cellular processes. NRs as therapeutic targets in liver disease have been exemplified by the successful application of their pharmacological ligands in clinics. MiRNA-based reagents or drugs are emerging as flagship products in clinical trials. Advancing our understanding of the crosstalk between NRs and ncRNAs is critical to the development of diagnostic and therapeutic strategies. This review summarizes recent findings on the reciprocal regulation between NRs and ncRNAs (mainly on miRNAs and lncRNAs) and their implication in liver pathophysiology, which might be informative to the translational medicine of targeting NRs and ncRNAs in liver disease.

Retrospective analysis of a dedicated care pathway for nonalcoholic fatty liver disease in an integrated US healthcare system demonstrates support of weight management and improved ALT

Background

A care pathway for nonalcoholic fatty liver disease (NAFLD) in Kaiser Permanente San Diego, California was instituted in August 2017 to improve efficiency of disease staging and promote lifestyle modification.

Methods

The NAFLD Care Pathway includes: (1) patient education (2) vibration controlled transient elastography (VCTE) examination (3) hepatology consultation for VCTE ≥ 8 kPa and (4) referral to weight management (WM). Patients referred to the pathway during the first 6 months of its implementation were studied for adherence to its components and impact on weight change and ALT values in the 12 months following referral. Retrospective assessment of WM participation, change in weight, and change in ALT were evaluated in the 12-months following referral and compared to changes 12-months prior. Student’s t-test or Wilcoxon signed rank test were used as appropriate (p < 0.05).

Results

632 patients were included. 575 (91.0%) completed VCTE examination with mean liver stiffness 8.5 kPa (SD 9.2). 52 patients had mean liver stiffness ≥ 15 kPa. 180/632 (28.5%) attended NAFLD education. 153/632 (24.2%) were offered hepatology clinic and 136/153 (88.9%) completed at least 1 appointment. Participation in WM was 24/632 (3.8%) prior to referral and 67/632 (10.6%) after referral and increased among patients who attended NAFLD education. Mean weight change following referral was − 0.69 kg (SD 6.58 kg) among patients without WM and − 7.78 kg (SD 13.43 kg) with WM. Overall, 44.2% of participants experienced weight gain after referral, 40.8% had weight loss < 5% and 15% had weight loss ≥ 5%. Variables associated with weight loss included WM (p < 0.0001) and higher liver stiffness (p = 0.0066). Mean ALT change was − 15.2 (SD 38.5) U/L without WM and − 28.8 (SD 29.6) U/L with WM.

Conclusions

A care pathway for NAFLD within a large, integrated healthcare system provides non-invasive disease staging and minimizes hepatology clinic utilization to those with more advanced disease. Referral was associated with increased enrollment in WM, weight loss, and decreased ALT. Given its impact on healthcare resources, strategies to improve NAFLD identification, staging, and promotion of lifestyle modification are imperative.

Volixibat in adults with non-alcoholic steatohepatitis: 24-week interim analysis from a randomized, phase II study

BACKGROUND & AIMS

Volixibat is an inhibitor of the apical sodium-dependent bile acid transporter (ASBT) that has been hypothesized to improve non-alcoholic steatohepatitis (NASH) by blocking bile acid reuptake and stimulating hepatic bile acid production. We studied the safety, tolerability and efficacy of volixibat in patients with NASH.

METHODS

In this double-blind, phase II dose-finding study, adults with ≥5% steatosis and NASH without cirrhosis (N = 197) were randomized to receive volixibat (5, 10 or 20 mg) or placebo once daily for 48 weeks. The endpoints of a predefined interim analysis (n = 80), at week 24, were: ≥5% reduction in MRI-proton density fat fraction and ≥20% reduction in serum alanine aminotransferase levels. The primary endpoint was a ≥2-point reduction in non-alcoholic fatty liver disease activity score without worsening fibrosis at week 48.

RESULTS

Volixibat did not meet either interim endpoint; the study was terminated owing to lack of efficacy. In participants receiving any volixibat dose, mean serum 7-alpha-hydroxy-4-cholesten-3-one (C4; a biomarker of bile acid synthesis) increased from baseline to week 24 (+38.5 ng/ml [SD 53.18]), with concomitant decreases in serum total cholesterol (-14.5 mg/dl [SD 28.32]) and low-density lipoprotein cholesterol (-16.1 mg/dl [SD 25.31]). These changes were generally dose-dependent. On histological analysis, a greater proportion of participants receiving placebo (38.5%, n = 5/13) than volixibat (30.0%, n = 9/30) met the primary endpoint. Treatment-emergent adverse events (TEAEs) were mainly mild or moderate. No serious TEAEs were related to volixibat. Diarrhoea was the most common TEAE overall and the most common TEAE leading to discontinuation.

CONCLUSIONS

Increased serum C4 and decreased serum cholesterol levels provide evidence of target engagement. However, inhibition of ASBT by volixibat did not elicit a liver-related therapeutic benefit in adults with NASH.

LAY SUMMARY

A medicine called volixibat has previously been shown to reduce cholesterol levels in the blood. This study investigated whether volixibat could reduce the amount of fat in the liver and reduce liver injury in adults with an advanced form of non-alcoholic fatty liver disease. Volixibat did not reduce the amount of fat in the liver, nor did it have any other beneficial effect on liver injury. Participants in the study generally tolerated the side effects of volixibat and, as in previous studies, the main side effect was diarrhoea. These results show that volixibat is not an effective treatment for people with fatty liver disease.

CLINICAL TRIAL IDENTIFIER

NCT02787304.

The therapeutic potential of C-C chemokine receptor antagonists in nonalcoholic steatohepatitis

Pooled prevalence of nonalcoholic fatty liver disease (NAFLD) globally is about 25%. Nonalcoholic steatohepatitis (NASH) with advanced fibrosis has been linked with substantial morbidity and mortality, without having to-date any licensed treatment. C-C chemokine receptor (CCR) antagonists have been investigated as candidates for the treatment of NASH. Inhibition of CCR2 is expected to mitigate hepatic inflammation, through reducing the activation of Kupffer cells, as well as the infiltration of monocytes and macrophages into the liver. Inhibition of CCR5 is expected to mitigate hepatic fibrogenesis, through impairing the activation of hepatic stellate cells, as well as to mitigate hepatic inflammation, through impairing the activation of Kupffer cells and macrophages. Cenicriviroc (CVC) is the first in class, dual inhibitor of CCR2 and CCR5. After exhibiting favorable results in animal models, CVC was shown to be beneficial in NASH patients with more severe fibrosis at a phase 2b trial (CENTAUR) and is currently at a phase 3 clinical trial (AURORA). Apart from CVC, other CCR5 mono-antagonists, such as maraviroc, are under evaluation in clinical trials with human immunodeficiency virus patients with NAFLD. The aim of this review was to summarize existing evidence on CVC and other CCR antagonists in NASH patients, primarily focusing on their clinical efficacy and safety.

Molecular mechanisms of hepatic insulin resistance in nonalcoholic fatty liver disease and potential treatment strategies

The prevalence of nonalcoholic fatty liver disease (NAFLD) in the general population is estimated at 25 %, and there is currently no effective treatment of NAFLD. Although insulin resistance (IR) is not the only factor causing the pathogenesis of NAFLD, hepatic IR has a cause-effective relationship with NAFLD. Improving hepatic IR is a potential therapeutic strategy to treat NAFLD. This review highlights the molecular mechanisms of hepatic IR in the development of NAFLD. Available data on potential drugs including glucagon-like peptide 1 receptor (GLP-1) agonists, peroxisome proliferator-activated receptor (PPAR-γ/α/δ) agonists, farnesoid X receptor (FXR) agonists, etc. are carefully discussed.

CONTROL: A randomized phase 2 study of obeticholic acid and atorvastatin on lipoproteins in nonalcoholic steatohepatitis patients

BACKGROUND & AIMS

Nonalcoholic steatohepatitis (NASH) is a chronic and severe form of nonalcoholic fatty liver disease that can progress to cirrhosis and hepatocellular carcinoma and is a risk factor for cardiovascular disease. Although NASH has no approved treatments, obeticholic acid (OCA), a synthetic bile acid and farnesoid X receptor (FXR) agonist, was shown to improve histological features of NASH and fibrosis. Considering that FXR activation influences plasma lipoprotein concentrations, the Combination OCA aNd sTatins for monitoRing Of Lipids (CONTROL) study evaluated how statins can regulate lipoprotein metabolism with OCA treatment in patients with NASH.

METHODS

This randomized, double-blind, placebo-controlled, phase 2 study began with a 5-week screening/statin washout; 84 patients with NASH were randomly assigned (1:1:1:1) to receive placebo or 5 mg, 10 mg or 25 mg OCA once daily during the 16-week double-blind phase. Concurrent once daily atorvastatin (10 mg/days) was initiated at Week 4 with subsequent titration. Enrolled patients had biopsy-confirmed diagnosis of NASH with no evidence of hepatic decompensation. Plasma was collected to analyse lipoprotein parameters.

RESULTS

At Week 4, all OCA groups had an increase from baseline in mean low-density lipoprotein cholesterol (LDLc) and mean LDL particle concentration (LDLpc), mostly owing to large, less atherogenic LDLc particles. Atorvastatin 10 mg decreased LDLc and LDLpc levels below baseline in all OCA groups by Week 8; higher doses did not provide additional clinical benefits.

CONCLUSIONS

The CONTROL study showed that OCA-induced increases in LDLc in patients with NASH were mitigated with atorvastatin. The combination of OCA and atorvastatin was generally safe and well tolerated (NCT02633956).

MiR-29 Regulates de novo Lipogenesis in the Liver and Circulating Triglyceride Levels in a Sirt1-Dependent Manner

MicroRNAs (miRNAs) are known regulators of lipid homeostasis. We recently demonstrated that miR-29 controls the levels of circulating cholesterol and triglycerides, but the mechanisms remained unknown. In the present study, we demonstrated that systemic delivery of locked nucleic acid inhibitor of miR-29 (LNA29) through subcutaneous injection effectively suppresses hepatic expression of miR-29 and dampens de novo lipogenesis (DNL) in the liver of chow-fed mice. Next, we used mice with liver-specific deletion of Sirtuin 1 (L-Sirt1 KO), a validated target of miR-29, and demonstrated that the LNA29-induced reduction of circulating triglycerides, but not cholesterol, is dependent on hepatic Sirt1. Moreover, lipidomics analysis revealed that LNA29 suppresses hepatic triglyceride levels in a liver-Sirt1 dependent manner. A comparative transcriptomic study of liver tissue from LNA29-treated wild-type/floxed and L-Sirt1 KO mice identified the top candidate lipogenic genes and hepatokines through which LNA29 may confer its effects on triglyceride levels. The transcriptomic analysis also showed that fatty acid oxidation (FAO) genes respond differently to LNA29 depending on the presence of hepatic Sirt1. Overall, this study demonstrates the beneficial effects of LNA29 on DNL and circulating lipid levels. In addition, it provides mechanistic insight that decouples the effect of LNA29 on circulating triglycerides from that of circulating cholesterol.

From "two hit theory" to "multiple hit theory": Implications of evolution of pathogenesis concepts for treatment of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is becoming a burgeoning and burdensome public health problem worldwide, along with diabetes and metabolic syndrome. In the NAFLD spectrum, non-alcoholic steatohepatitis can progress to hepatic fibrosis, especially progressive fibrosis, which can lead to cirrhosis or even hepatocellular carcinoma. However, the pathogenesis of NAFLD is extremely complex and has not yet been fully elucidated, thus there is a lack of effective treatment. In recent years, the classic "two-hit" hypothesis has been gradually surpassed and supplemented by a great deal of findings, and the "multiple hit" hypothesis has been proposed and is being accepted. The study on the interaction among cellular and molecular mechanisms, environmental and genetic factors has revealed a number of critical targets in the pathogenesis of NAFLD, providing broad directions for the development of diagnostic markers and targeted therapeutic drugs. Here we elaborate the latest advances in understanding the pathogenesis of NAFLD from multiple perspectives, in order to analyze and evaluate the prospect of developing diagnostic biomarkers and therapeutic targets based on those pathogeneses.

A multidisciplinary approach to the management of NAFLD is associated with improvement in markers of liver and cardio-metabolic health

Non-alcoholic fatty liver disease (NAFLD) is a globally prevalent health problem, associated in its more severe forms with increased liver-related and cardiovascular-related morbidity and mortality. We established a multidisciplinary metabolic hepatology clinic in 2014 and have analysed the clinical data to evaluate the effectiveness of this service. Patients with NAFLD (n=165) who had attended two or more appointments were included. Prespecified clinical data were collected prospectively at clinic appointments and analysed retrospectively. Interventions offered included lifestyle advice, signposting to weight loss services and pharmacological treatment of diabetes and cardiovascular risk factors. Median follow-up was 13 months (range: 2-34). 59% (n=97) of patients had type 2 diabetes mellitus (T2DM). 53% (n=87) underwent liver biopsy of whom 18% (n=16) had cirrhosis. Median alanine aminotransferase (ALT) reduced by 11 IU/L (p<0.0001), median weight reduced by 3.3 kg (p=0.0005). There were significant reductions in HbA1c, total cholesterol and liver stiffness. Specifically, in patients with T2DM, HbA1c decreased by 4 mmol/mol (p=0.01) with significant reductions in ALT, weight and total cholesterol. Relative cardiovascular risk assessed by the QRISK3 score reduced in the whole cohort and in those with T2DM. Health economic modelling suggested the clinic intervention among those patients with poorly controlled T2DM was cost-effective. In conclusion, a multidisciplinary approach to the management of patients with NAFLD in this observational cohort study was associated with improvements in liver-related and cardio-metabolic related health parameters and with evidence of cost-effectiveness in patients with poorly controlled T2DM.

Improvement of non-invasive markers of NAFLD from an individualised, web-based exercise program

BACKGROUND

Lifestyle modifications remain the cornerstone of treatment in non-alcoholic fatty liver disease (NAFLD). However, they requently fail related to the inability of patients to implement lasting changes.

AIMS

To evaluate the effects of a short, web-based, individualised exercise program on non-invasive markers of hepatic steatosis, inflammation and fibrosis.

METHODS

Patients with histologically confirmed NAFLD underwent an 8-week, web-based, individualised exercise program that contained bidirectional feedback.

RESULTS

Forty-four patients entered the study and 41 completed the assigned training goal (93.2%). In the completer population, 8 weeks of individualised exercise increased the VO_2peak by 12.2% compared to baseline (P < .001). ALT and AST decreased by 14.3% (P = .002) and 18.2% (P < .001) and remained at this level until follow-up 12 weeks after the intervention. Markers of inflammation including hsCRP, ferritin, and M30 decreased. In parallel, gut microbiota exhibited increased metagenomic richness (P < .05) and at the taxonomic levels Bacteroidetes and Euryarchaeota increased whereas Actinobacteria phylum decreased. Surrogate scores of steatosis and fibrosis including the fatty liver index (FLI), FiB-4, APRI and transient elastography showed significant reductions. In parallel, a marker of procollagen-3 turnover (PRO-C3) decreased while C4M2, reflecting type IV collagen, degradation increased suggesting beneficial hepatic fibrosis remodelling from exercise. Also, an enhancement in health-related quality of life was reported.

CONCLUSION

The current study underlines the plausibility and potential of an 8 week individualised web-based exercise program in NAFLD. Clinical trial number: NCT02526732.

Nonalcoholic Fatty Liver Disease and Diabetes: Part II: Treatment

Nonalcoholic fatty liver disease (NAFLD) and diabetes are common metabolic disorders that are often comorbid conditions. Among many proposed treatments, weight reduction is the only approved option for NAFLD to date. However, it is not easy to maintain weight loss by lifestyle modification alone; pharmacological treatments are helpful in this regard. Although many drugs have been investigated, pioglitazone could be a first-line therapy in patients with NAFLD and diabetes. Many more drugs are currently being developed and investigated, and it is likely that combination strategies will be used for future treatment of NAFLD and diabetes. Attention should be paid to the management of NAFLD and diabetes and efforts should be made to intervene early and individualize treatment of NAFLD in patients with diabetes.

Non-alcoholic fatty liver disease: causes, diagnosis, cardiometabolic consequences, and treatment strategies

The prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing worldwide. In some patients with NAFLD, isolated steatosis can progress to advanced stages with non-alcoholic steatohepatitis (NASH) and fibrosis, increasing the risk of cirrhosis and hepatocellular carcinoma. Furthermore, NAFLD is believed to be involved in the pathogenesis of common disorders such as type 2 diabetes and cardiovascular disease. In this Review, we highlight novel concepts related to diagnosis, risk prediction, and treatment of NAFLD. First, because NAFLD is a heterogeneous disease, the advanced stages of which seem to be strongly affected by comorbidities such as insulin resistance and type 2 diabetes, early use of reliable, non-invasive diagnostic tools is needed, particularly in patients with insulin resistance or diabetes, to allow the identification of patients at different disease stages. Second, although the strongest genetic risk alleles for NAFLD (ie, the 148Met allele in PNPLA3 and the 167Lys allele in TM6SF2) are associated with increased liver fat content and progression to NASH and cirrhosis, these alleles are also unexpectedly associated with an apparent protection from cardiovascular disease. If consistent across diverse populations, this discordance in NAFLD-related risk prediction between hepatic and extrahepatic disease might need to be accounted for in the management of NAFLD. Third, drug treatments assessed in NAFLD seem to differ with respect to cardiometabolic and antifibrotic efficacy, suggesting the need to better identify and tailor the most appropriate treatment approach, or to use a combination of approaches. These emerging concepts could contribute to the development of a multidisciplinary approach for endocrinologists and hepatologists working together in the management of NAFLD.

Folate receptor-beta expression as a diagnostic target in human & rodent nonalcoholic steatohepatitis

INTRODUCTION

Nonalcoholic steatohepatitis (NASH) afflicts 20-36% of individuals with nonalcoholic fatty liver disease (NAFLD). A lipotoxic hepatic environment, altered innate immune signaling and inflammation are defining features of progression to NASH. Activated resident liver macrophages express folate receptor beta (FR-β) which may be an indicator of progression from steatosis to NASH. The goals of this study were to characterize FR-β protein expression in human NAFLD and rodent models of NASH, and demonstrate liver targeting of an FR-β imaging agent to the liver of a rodent NASH model using FR-β.

METHODS

Rat liver lysates from methionine choline deficient (MCD) fed rats, high fat diet (HFD) and methionine choline sufficient (MC+) rat controls were analyzed for hepatic FR-β protein. The FR-β-targeted agent, Etarfolatide was injected into MCD and MC + -fed C57BL/6 mice for efficient FastSPECT hepatic imaging. Additionally, FR-β expression across the stages of human NAFLD from normal to NASH was assessed.

RESULTS

FastSPECT images show targeting of Etarfolatide to the liver of mice fed 8 weeks of MCD diet but not control-fed mice. The MCD rat model exhibited significantly increased protein expression of hepatic FR-β in contrast to HFD or normal samples. Similarly human liver samples categorized as NASH Fatty or NASH Not Fatty showed elevated FR-β protein when compared to normal liver. FR-β transcript expression levels were elevated across both NASH Fatty and NASH Not Fatty samples.

CONCLUSION

The findings in this study indicate that FR-β expression in NASH may be harnessed to target agents directly to the liver.

A round trip from nonalcoholic fatty liver disease to diabetes: molecular targets to the rescue?

Evidence suggests a close relationship between nonalcoholic fatty liver disease (NAFLD) and type two diabetes (T2D). On the grounds of prevalence of disease, both conditions account for a significant financial cost for health care systems and individuals. Aim of this review article is to explore the epidemiological basis and the putative molecular mechanisms underlying the association of NAFLD with T2D. Epidemiological studies have shown that NAFLD is associated to the development of incident T2D and either reversal or improvement of NAFLD will result into decreased risk of developing incident T2D. On the other side of the coin data have shown that T2D will worsen the course of NAFLD doubling the risk of disease progression (i.e. evolution from simple steatosis to advanced fibrosis, cirrhosis, hepatocellular carcinoma, liver transplant and death). Conversely, NAFLD will contribute to metabolic decompensation of T2D. The pathogenesis of T2D in NAFLD patients may be mediated by several hepatokines impairing metabolic control. Among these, Fetuin-B, which causes glucose intolerance and is increased in patients with T2D and NAFLD with fibrosis is one of the most promising. T2D may affect the progression of NAFLD by acting at different levels of the pathogenic cascade involving gut microbiota and expanded, inflamed, dysfunctional adipose tissue. In conclusion, T2D and NAFLD are mutually, closely and bi-directionally associated. An improved understanding of molecular pathogenesis underlying this bi-directional association may allow us to be able to prevent the development of T2D by halting the progression of NAFLD.

Insights into the Epidemiology, Pathogenesis, and Therapeutics of Nonalcoholic Fatty Liver Diseases

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease which affects ≈25% of the adult population worldwide, placing a tremendous burden on human health. The disease spectrum ranges from simple steatosis to steatohepatitis, fibrosis, and ultimately, cirrhosis and carcinoma, which are becoming leading reasons for liver transplantation. NAFLD is a complex multifactorial disease involving myriad genetic, metabolic, and environmental factors; it is closely associated with insulin resistance, metabolic syndrome, obesity, diabetes, and many other diseases. Over the past few decades, countless studies focusing on the investigation of noninvasive diagnosis, pathogenesis, and therapeutics have revealed different aspects of the mechanism and progression of NAFLD. However, effective pharmaceuticals are still in development. Here, the current epidemiology, diagnosis, animal models, pathogenesis, and treatment strategies for NAFLD are comprehensively reviewed, emphasizing the outstanding breakthroughs in the above fields and promising medications in and beyond phase II.

Inhibition of sodium glucose cotransporter 2 (SGLT2) delays liver fibrosis in a medaka model of nonalcoholic steatohepatitis (NASH)

The rise in the incidence of nonalcoholic steatohepatitis (NASH) has necessitated the development of an effective prevention methodology. An antidiabetic drug, belonging to the group of sodium glucose cotransporter 2 (SGLT2) inhibitors, has been tested for its therapeutic effect on NASH; however, no studies to date have demonstrated the preventive effect of an SGLT2 inhibitor on the histological progression of steatosis and fibrosis in a sequential manner in animal models. In the present study, we examined the effect of the SGLT2 inhibitor, tofogliflozin (Tofo), on NASH liver tissue using medaka as an animal model, maintaining a feeding amount and drug concentration in all animal bodies. We generated a medaka NASH model by feeding d‐rR/Tokyo medaka a high‐fat diet and administered Tofo by dissolving the drug directly in the water of the feeding tank. Thereafter, the effects of Tofo on body weight (BW), liver weight, hepatotoxicity, fatty infiltration, and fibrotic changes in the liver were examined. We report here that SGLT2 is expressed in medaka fish and that Tofo inhibits the accumulation of fatty tissue and delays the progression of liver fibrosis in the medaka NASH model by inhibiting increases in blood sugar, serum lipids, and transaminase, irrespective of changes in BW. These results suggest that Tofo is effective for treating NASH and that the medaka model may be useful for developing new therapeutic drugs for this disease.

Asking the Right Questions With Animal Models: Methionine- and Choline-Deficient Model in Predicting Adverse Drug Reactions in Human NASH

In the past few decades, great conceptual and technological advances have been made in the field of toxicology, but animal model-based research still remains one of the most widely used and readily available tools for furthering our current knowledge. However, animal models are not perfect in predicting all systemic toxicity in humans. Extrapolating animal data to accurately predict human toxicities remains a challenge, and researchers are obligated to question the appropriateness of their chosen animal model. This paper provides an assessment of the utility of the methionine- and choline-deficient (MCD) diet fed animal model in reflecting human nonalcoholic steatohepatitis (NASH) and the potential risks of adverse drug reactions and toxicities that are associated with the disease. As a commonly used NASH model, the MCD model fails to exhibit most metabolic abnormalities in a similar manner to the human disease. The MCD model, on the other hand, closely resembles human NASH histology and reflects signatures of drug transporter alterations in humans. Due to the nature of the MCD model, it should be avoided in studies of NASH pathogenesis, metabolic parameter evaluation, and biomarker identification. But it can be used to accurately predict altered drug disposition due to NASH-associated transporter alterations.

An internet-based approach for lifestyle changes in patients with NAFLD: Two-year effects on weight loss and surrogate markers

BACKGROUND & AIMS

Interventions aimed at lifestyle changes are pivotal for the treatment of non-alcoholic fatty liver disease (NAFLD), and web-based programs might help remove barriers in both patients and therapists.

METHODS

In the period 2010-15, 716 consecutive NAFLD cases (mean age, 52; type 2 diabetes, 33%) were treated in our Department with structured programs. The usual protocol included motivational interviewing and a group-based intervention (GBI), chaired by physicians, dietitians and psychologists (five weekly meetings, n = 438). Individuals who could not attend GBI entered a web-based intervention (WBI, n = 278) derived from GBI, with interactive games, learning tests, motivational tests, and mail contacts with the center. The primary outcome was weight loss ≥10%; secondary outcomes were alanine aminotransferase within normal limits, changes in lifestyle, weight, alanine aminotransferase, and surrogate markers of steatosis and fibrosis.

RESULTS

GBI and WBI cohorts had similar body mass index (mean, 33 kg/m²), with more males (67% vs. 45%), younger age, higher education, and more physical activity in the WBI group. The two-year attrition rate was higher in the WBI group. Healthy lifestyle changes were observed in both groups and body mass index decreased by almost two points;the 10% weight target was reached in 20% of WBI cases vs. 15% in GBI (not significant). In logistic regression analysis, after adjustment for confounders and attrition rates, WBI was not associated with a reduction of patients reaching short- and long-term 10% weight targets. Liver enzymes decreased in both groups, and normalized more frequently in WBI. Fatty liver index was reduced, whereas fibrosis remained stable (NAFLD fibrosis score) or similarly decreased (Fib-4).

CONCLUSION

WBI is not less effective than common lifestyle programs, as measured by significant clinical outcomes associated with improved histological outcomes in NAFLD. eHealth programs may effectively contribute to NAFLD control.

LAY SUMMARY

In patients with non-alcoholic fatty liver disease, participation in structured lifestyle programs may be jeopardized by job and time constraints. A web-based intervention may be better suited for young, busy patients, and for those living far from liver units. The study shows that, following a structured motivational approach, a web-based, interactive intervention coupled with six-month face-to-face meetings is not inferior to a standard group-based intervention with respect to weight loss, adherence to healthy diet and habitual physical activity, normalization of liver enzymes, and stable surrogate markers of fibrosis.

The chemokine system and its role in obesity

The chemokine system is a complex arrangement of molecules that attract leukocytes to the site of injury or inflammation. This chemotactic behavior gives the system the name "Chemokine." The intricate and redundant nature of the chemokine system has made it a subject of ongoing scientific investigation. Obesity is characterized as low-grade systemic or chronic inflammation that is responsible for the release of cytokines, adipokines, and chemokines. Excessive tissue fat expansion triggers the release of chemokines, which in turn attract various leukocytes and activate the resident immune surveillance system, eventually leading to worsening of obesity and other related comorbidities. To date, 50 chemokines and 20 chemokine receptors that belong to the G-protein-coupled receptor family have been discovered, and over the past two decades, the physiological and pathological roles of many of these chemokines and their receptors have been elucidated. The objective of this review is to present an update on the link between chemokines and obesity under the light of recent knowledge.

Pharmacotherapy of type 2 diabetes in patients with chronic liver disease: focus on nonalcoholic fatty liver disease

INTRODUCTION

Pharmacotherapy used to treat type 2 diabetes mellitus (T2DM) is facing a paradigm shift in clinical practice with recent cardiovascular (CV) outcome trials having a substantial impact on drug prescription with treatment having a more tailored approach. In patients with T2DM, the issue of chronic liver disease is multifaceted. However, a clinical evidence is emerging on the beneficial effect of antidiabetic medications on nonalcoholic fatty liver disease (NAFLD).

AREAS COVERED

The authors provide a synopsis on the current and upcoming pharmacotherapy for NAFLD, including the challenges with their development, focusing on drugs for T2DM. Clinical data on the potential benefits and safety issues are assessed with the aim of proposing an individualized algorithm for patient management. Both MEDLINE and ClinicalTrials.Gov are used to derive the relevant information.

EXPERT OPINION

Considering the pivotal role of insulin resistance in NAFLD, insulin sensitizers should be the treatment of choice. Accordingly, pioglitazone is the only drug with a significant effect on liver fibrosis, the driver of disease progression and long-term outcome. Among new glucose-lowering drugs, glucagon-like-peptide 1 receptor agonists or sodium-glucose cotransporter type 2 inhibitors have shown positive effects in phase II studies and are qualifying as potential candidates for NAFLD treatment in diabetes.

Cross-Species Molecular Imaging of Bile Salts and Lipids in Liver: Identification of Molecular Structural Markers in Health and Disease

The liver is the primary organ involved in handling of bile salts, a class of amphipathic molecules with signaling activities as well as desired and detrimental detergent actions. To allow in-depth investigation of functions of bile salts in healthy and diseased liver, the spatial distribution of bile salt species within the liver needs to be studied. Therefore, the aim of our study was to determine hepatic bile salt distribution and identify specific lipid markers that define the structural elements of the liver. Matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) was used to monitor the spatial distribution of bile salts and lipids in liver sections of rat, dog, and patients with unaffected and cholestatic parenchyma. MALDI-MSI in negative ion mode showed the local presence of a variety of bile salts, predominantly taurine-conjugates, as localized patches of varying sizes (representing the bile ducts) throughout the liver tissue. Specific molecular markers were identified for the connective tissue (phosphatidic acids, e.g., [PA (18:0_18:1)–H]⁻), the liver parenchyma (phosphatidylinositols, e.g., [PI (18:0_20:4)-H]⁻), and the bile ducts (hydroxylated-sulfatides, e.g., [ST–OH (18:1_24:0)-H]⁻). One of these sulfatides (at m/z 906.6339) was found to be uniquely localized in a thin lining on the inside of the bile duct, colocalized with cytokeratins, and encased luminal bile salts. A similar distribution of the aforementioned sulfatide was observed, albeit in constricted ductular structures, in the liver of a patient with a mild clinical phenotype of primary sclerosing cholangitis (PSC). In contrast, sulfatides were virtually absent in the liver of patients with PSC and a severe clinical phenotype, with (atypical) cholanoids (e.g., the bile alcohol 5-cyprinolsulfate) abundant in the extra-ductular space and glyco(cheno)deoxycholic acid-3-sulfate localized to fibrotic connective tissue. The latter two molecular species were able to discriminate between healthy liver tissue (n = 3) and tissue from PSC patients with a severe clinical phenotype (n = 3). In conclusion, the distinct structural elements of the mammalian liver are characterized by specific classes of lipids. We propose that (hydroxylated-)sulfatides are specific molecular markers of the bile duct.

Type and Pattern of Alcohol Consumption is Associated With Liver Fibrosis in Patients With Non-alcoholic Fatty Liver Disease

INTRODUCTION

It is unclear whether low levels of alcohol are harmful in patients with non-alcoholic fatty liver disease (NAFLD). We aimed to determine whether quantity, binge pattern consumption, or type of alcohol was associated with liver fibrosis in patients with NAFLD.

METHODS

Previous and current alcohol consumption was assessed in NAFLD patients undergoing liver biopsy. All subjects currently consumed <210 g per week (male) or <140 g per week (female). Binge consumption was defined as ≥4 standard drinks (female) or ≥5 standard drinks (male) in one sitting. Liver biopsies were scored according to the NASH CRN system with F3/4 fibrosis defined as advanced.

RESULTS

Among 187 patients (24% with advanced fibrosis), the median weekly alcohol consumption was 20 (2.3-60) g over an average of 18 years. Modest consumption (1-70 g per week) was associated with lower mean fibrosis stage compared to lifetime abstainers (p < 0.05) and a decreased risk of advanced fibrosis (OR 0.33, 95% CI 0.14-0.78, p = 0.01). The association with reduced fibrosis was not seen in subjects drinking in a binge-type fashion. Exclusive wine drinkers but not exclusive beer drinkers, had lower mean fibrosis stage and lower odds of advanced fibrosis (OR 0.20, 95% CI 0.06-0.69, p = 0.01), compared to lifetime abstinent subjects. No interaction between gender and alcohol quantity, type, or binge consumption on fibrosis was observed.

DISCUSSION

Modest (1-70 g per week) alcohol consumption, particularly wine in a non-binge pattern, is associated with lower fibrosis in patients with NAFLD. Prospective longitudinal studies into fibrosis progression, cardiovascular outcomes, and mortality are required before clinical recommendations can be made.

New insights into genetic predisposition and novel therapeutic targets for nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease in the United States affecting 80-100 million Americans. NAFLD encompasses a spectrum of diseases ranging from excess liver fat (nonalcoholic fatty liver or NAFL), to necro-inflammation (nonalcoholic steatohepatitis or NASH), to fibrosis/ cirrhosis, and malignant transformation (hepatocellular carcinoma). Susceptibility to NAFLD is highly variable and it remains unclear why some patients with NAFLD exhibit NASH, whereas patients with known risk factors have NAFL only. The reasons for this variability can be a partially attributed to differences in genetic background. In the last decade, there have been multiple genome wide association studies, which have enriched our understanding of the genetic basis of NAFLD. The I148M PNPLA3 (patatin-like phospholipase domain-containing protein 3) variant has been identified as the major common genetic determinant of NAFLD. Variants with moderate effect size like TM6SF2, MBOAT7 and GCKR have also been shown to have a significant contribution. New research has uncovered major pathways leading to disease development and progression; therefore, multiple medications are being developed and tested for the treatment of advanced NAFLD. These agents target metabolic mechanisms as well as inflammation and fibrosis pathways. Several randomized clinical trials (RCTs) are evaluating the efficacy of these novel agents on histological improvement of disease severity and decreasing liver-related outcomes. FDA-approved medications for NASH and NASH-related fibrosis are expected by 2020.

Practical Diagnosis and Staging of Nonalcoholic Fatty Liver Disease: A Narrative Review

As the rates of obesity increase worldwide, the prevalence of nonalcoholic fatty liver disease (NAFLD) has risen and it is now the most common cause of liver disease in the developed world. A significant proportion of patients with NAFLD develop nonalcoholic steatohepatitis and progressive liver fibrosis, which can lead to cirrhosis and its complications. NAFLD should be suspected in individuals who have central obesity and metabolic risk factors. A diagnosis of NAFLD can be made when patients have evidence of steatosis on imaging or if they have raised liver enzymes with a background of metabolic risk factors, provided other causes of liver disease and excessive alcohol consumption are excluded. Making a specific diagnosis of NAFLD is important so that affected individuals can receive specific treatment and be monitored for its complications. The stage of liver fibrosis is the most important prognostic factor so must be assessed in all patients; a number of simple blood tests and imaging modalities allow accurate fibrosis staging without the need for liver biopsy. The aim of this narrative review is to provide a practical overview relating to the diagnosis and staging of NAFLD using noninvasive tests that are widely available in primary and secondary care.

Screening for therapeutic trials and treatment indication in clinical practice: MACK-3, a new blood test for the diagnosis of fibrotic NASH

BACKGROUND

The composite histological endpoint comprising nonalcoholic steatohepatitis (NASH) and NAFLD activity score ≥4 and advanced fibrosis (F ≥ 2) ("fibrotic NASH") is becoming an important diagnostic target in NAFLD: it is currently used to select patients for inclusion in phase III therapeutic trials and will ultimately be used to indicate treatment in clinical practice once the new drugs are approved.

AIM

To develop a new blood test specifically dedicated for this new diagnostic target of interest.

METHODS

Eight Hundred and forty-six biopsy-proven NAFLD patients from three centres (Angers, Nice, Antwerp) were randomised into derivation and validation sets.

RESULTS

The blood fibrosis tests BARD, NFS and FIB4 had poor accuracy for fibrotic NASH with respective AUROC: 0.566 ± 0.023, 0.654 ± 0.023, 0.732 ± 0.021. In the derivation set, fibrotic NASH was independently predicted by AST, HOMA and CK18; all three were combined in the new blood test MACK-3 (hoMa, Ast, CK18) for which 90% sensitivity and 95% specificity cut-offs were calculated. In the validation set, MACK-3 had a significantly higher AUROC (0.847 ± 0.030, P ≤ 0.002) than blood fibrosis tests. Using liver biopsy in the grey zone between the two cut-offs (36.0% of the patients), MACK-3 provided excellent accuracy for the diagnosis of fibrotic NASH with 93.3% well-classified patients, sensitivity: 90.0%, specificity: 94.2%, positive predictive value: 81.8% and negative predictive value: 97.0%.

CONCLUSION

The new blood test MACK-3 accurately diagnoses fibrotic NASH. This new test will facilitate patient screening and inclusion in NAFLD therapeutic trials and will enable the identification of patients who will benefit from the treatments once approved.

Genetic and Epigenetic Regulation in Nonalcoholic Fatty Liver Disease (NAFLD)

Genetics and epigenetics play a key role in the development of several diseases, including nonalcoholic fatty liver disease (NAFLD). Family studies demonstrate that first degree relatives of patients with NAFLD are at a much higher risk of the disease than the general population. The development of the Genome Wide Association Study (GWAS) technology has allowed the identification of numerous genetic polymorphisms involved in the evolution of diseases (e.g., PNPLA3, MBOAT7). On the other hand, epigenetic changes interact with inherited risk factors to determine an individual’s susceptibility to NAFLD. Modifications of the histones amino-terminal ends are key factors in the maintenance of chromatin structure and gene expression (cAMP-responsive element binding protein H (CREBH) or SIRT1). Activation of SIRT1 showed potential against the physiological mechanisms related to NAFLD. Abnormal DNA methylation represents a starting point for cancer development in NAFLD patients. Besides, the evaluation of circulating miRNA profiles represents a promising approach to assess and non-invasively monitor liver disease severity. To date, there is no approved pharmacologic therapy for NAFLD and the current treatment remains weight loss with lifestyle modification and exercise. In this review, the status of research into relevant genetic and epigenetic modifiers of NAFLD progression will be discussed.

Global epidemiology of non-alcoholic fatty liver disease/non-alcoholic steatohepatitis: What we need in the future

The estimated prevalence of non-alcoholic fatty liver disease (NAFLD) worldwide is approximately 25%. However, the real prevalence of NAFLD and the associated disorders is unknown mainly because reliable and applicable diagnostic tests are lacking. This is further complicated by the lack of consensus on the terminology of different entities such as NAFLD or nonalcoholic steatohepatitis (NASH). Although assessing fatty infiltration in the liver is simple by ultrasound, the gold standard for the assessment of fibrosis, the only marker of progression towards more severe liver disease is still liver biopsy. Although other non-invasive tests have been proposed, they must still be validated in large series. Because NAFL/NAFLD/NASH and related metabolic diseases represent an economic burden, finding an inexpensive method to diagnose and stage fatty liver is a priority. A translational approach with the use of cell and/or animal models could help to reach this goal.

Nonalcoholic fatty liver disease and chronic vascular complications of diabetes mellitus

Nonalcoholic fatty liver disease (NAFLD) and diabetes mellitus are common diseases that often coexist and might act synergistically to increase the risk of hepatic and extra-hepatic clinical outcomes. NAFLD affects up to 70-80% of patients with type 2 diabetes mellitus and up to 30-40% of adults with type 1 diabetes mellitus. The coexistence of NAFLD and diabetes mellitus increases the risk of developing not only the more severe forms of NAFLD but also chronic vascular complications of diabetes mellitus. Indeed, substantial evidence links NAFLD with an increased risk of developing cardiovascular disease and other cardiac and arrhythmic complications in patients with type 1 diabetes mellitus or type 2 diabetes mellitus. NAFLD is also associated with an increased risk of developing microvascular diabetic complications, especially chronic kidney disease. This Review focuses on the strong association between NAFLD and the risk of chronic vascular complications in patients with type 1 diabetes mellitus or type 2 diabetes mellitus, thereby promoting an increased awareness of the extra-hepatic implications of this increasingly prevalent and burdensome liver disease. We also discuss the putative underlying mechanisms by which NAFLD contributes to vascular diseases, as well as the emerging role of changes in the gut microbiota (dysbiosis) in the pathogenesis of NAFLD and associated vascular diseases.

The Emerging Role of GLP-1 Receptors in DNA Repair: Implications in Neurological Disorders

Glucagon-like peptide-1 (GLP-1) is originally found as a metabolic hormone (incretin) that is able to regulate blood-glucose levels via promoting synthesis and secretion of insulin. GLP-1 and many analogues are approved for treatment of type II diabetes. Accumulating results imply that GLP-1 performs multiple functions in various tissues and organs beyond regulation of blood-glucose. The neuroprotective function of GLP-1 has been extensively explored during the past two decades. Three of our previous studies have shown that apurinic/apyrimidinic endonuclease 1 (APE1) is the only protein of the base excision repair (BER) pathway able to be regulated by oxidative stress or exogenous stimulations in rat primary cortical neurons. In this article, we review the role of APE1 in neurodegenerative diseases and its relationship to neuroprotective mechanisms of the activated GLP-1 receptor (GLP-1R) in neurodegenerative disorders. The purpose of this article is to provide new insight, from the aspect of DNA damage and repair, for studying potential treatments in neurodegenerative diseases.