Nonalcoholic Fatty Liver Disease: Epidemiology, Pathogenesis, Natural History, Diagnosis, and Current Treatment Options

The effects of simvastatin-loaded nanoliposomes on human multilineage liver fibrosis microtissue

In this in vitro study, for the first time, we evaluate the effects of simvastatin-loaded liposome nanoparticles (SIM-LipoNPs) treatment on fibrosis-induced liver microtissues, as simvastatin (SIM) has shown potential benefits in the non-alcoholic fatty liver disease process. We developed multicellular liver microtissues composed of hepatic stellate cells, hepatoblastoma cells and human umbilical vein endothelial cells. The microtissues were supplemented with a combination of palmitic acid and oleic acid to develop fibrosis models. Subsequently, various groups of microtissues were exposed to SIM and SIM-LipoNPs at doses of 5 and 10 mg/mL. The effectiveness of the treatments was evaluated by analysing cell viability, production of reactive oxygen species (ROS) and nitric oxide (NO), the expression of Kruppel-like factor (KLF) 2, and pro-inflammatory cytokines (interleukin(IL)-1 α, IL-1 β, IL-6 and tumour necrosis factor-α), and the expression of collagen I. Our results indicated that SIM-LipoNPs application showed promising results. SIM-LipoNPs effectively amplified the SIM-klf2-NO pathway at a lower dosage compatible with a high dosage of free SIM, which also led to reduced oxidative stress by decreasing ROS levels. SIM-LipoNPs administration also resulted in a significant reduction in pro-inflammatory cytokines and Collagen I mRNA levels, as a marker of fibrosis. In conclusion, our study highlights the considerable therapeutic potential of using SIM-LipoNPs to prevent liver fibrosis progress, underscoring the remarkable properties of SIM-LipoNPs in activating the KLF2-NO pathway and anti-oxidative and anti-inflammatory response.

The impact of piperine on the metabolic conditions of patients with NAFLD and early cirrhosis: a randomized double-blind controlled trial

Non-alcoholic fatty liver disease (NAFLD) is a metabolic dysfunction of the liver defined as an abnormal accumulation of fat within the liver without secondary triggers like alcohol consumption or viral hepatitis. Piperine, the bio-active ingredient of black pepper, can exert a significant function in treatment of individuals with NAFLDand early cirrhosis. We investigated the impact of piperine consumption with a duration of 12 weeks on patients with NAFLD and early cirrhosis compared toplacebo consumption. In a double-blind study, patients with NAFLD and early stage of cirrhosis were haphazardly distributed into case and control groups. They were prescribed a placebo and 5 mg of piperine for 12 weeks, respectively. The demographic and laboratory parameters of individuals were assessed as the baseline and after the duration of piperine intake. Piperine with a daily dosage of 5 mg could significantly decrease hepatic enzymes and glucose, and alleviate dyslipidemia in the case arm rather than the control arm. Moreover, HOMA levels and insulin resistance were reduced in case participants compared to the control counterparts. In the absence of approved medicinal intervention for patients with NAFLD, and regarding the favorable impact of piperine on NAFLD more studies on this subject are warranted.

Atorvastatin on Treatment of Nonalcoholic Fatty Liver Disease Patients

Non-alcoholic fatty liver disease (NAFLD) is a condition in which excess fat builds up in the liver, often related to obesity and insulin resistance, which can lead to inflammation and scarring of the liver tissue. While efforts have been made to develop effective treatments for NAFLD, the need for pharmaceutical interventions remains unmet. Large clinical trials investigating the association between statin use and NAFLD are scarce, leading to contradictory results. Statins play a crucial role in cholesterol synthesis in the liver. Several studies have demonstrated that statins possess anti-inflammatory, anti-thrombotic, and anti-fibrotic properties. These properties make statins potentially useful in preventing the progression of NAFLD from simple steatosis to more severe forms like non-alcoholic steatohepatitis (NASH) and fibrosis. The results indicate that statin use is associated with a lower prevalence of NASH and fibrosis and may have a preventive effect on NAFLD.

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.

Saturated fatty acid-enriched small extracellular vesicles mediate a crosstalk inducing liver inflammation and hepatocyte insulin resistance

Background & Aims

Lipotoxicity triggers non-alcoholic fatty liver disease (NAFLD) progression owing to the accumulation of toxic lipids in hepatocytes including saturated fatty acids (SFAs), which activate pro-inflammatory pathways. We investigated the impact of hepatocyte- or circulating-derived small extracellular vesicles (sEV) secreted under NAFLD conditions on liver inflammation and hepatocyte insulin signalling.

Methods

sEV released by primary mouse hepatocytes, characterised and analysed by lipidomics, were added to mouse macrophages/Kupffer cells (KC) to monitor internalisation and inflammatory responses. Insulin signalling was analysed in hepatocytes exposed to conditioned media from sEV-loaded macrophages/KC. Mice were i.v. injected sEV to study liver inflammation and insulin signalling. Circulating sEV from mice and humans with NAFLD were used to evaluate macrophage-hepatocyte crosstalk.

Results

Numbers of sEV released by hepatocytes increased under NAFLD conditions. Lipotoxic sEV were internalised by macrophages through the endosomal pathway and induced pro-inflammatory responses that were ameliorated by pharmacological inhibition or deletion of Toll-like receptor-4 (TLR4). Hepatocyte insulin signalling was impaired upon treatment with conditioned media from macrophages/KC loaded with lipotoxic sEV. Both hepatocyte-released lipotoxic sEV and the recipient macrophages/KC were enriched in palmitic (C16:0) and stearic (C18:0) SFAs, well-known TLR4 activators. Upon injection, lipotoxic sEV rapidly reached KC, triggering a pro-inflammatory response in the liver monitored by Jun N-terminal kinase (JNK) phosphorylation, NF-κB nuclear translocation, pro-inflammatory cytokine expression, and infiltration of immune cells into the liver parenchyma. sEV-mediated liver inflammation was attenuated by pharmacological inhibition or deletion of TLR4 in myeloid cells. Macrophage inflammation and subsequent hepatocyte insulin resistance were also induced by circulating sEV from mice and humans with NAFLD.

Conclusions

We identified hepatocyte-derived sEV as SFA transporters targeting macrophages/KC and activating a TLR4-mediated pro-inflammatory response enough to induce hepatocyte insulin resistance.

Impact and Implications

Small extracellular vesicles (sEV) released by the hepatocytes under non-alcoholic fatty liver disease (NAFLD) conditions cause liver inflammation and insulin resistance in hepatocytes via paracrine hepatocyte-macrophage-hepatocyte crosstalk. We identified sEV as transporters of saturated fatty acids (SFAs) and potent lipotoxic inducers of liver inflammation. TLR4 deficiency or its pharmacological inhibition ameliorated liver inflammation induced by hepatocyte-derived lipotoxic sEV. Evidence of this macrophage-hepatocyte interactome was also found in patients with NAFLD, pointing to the relevance of sEV in SFA-mediated lipotoxicity in NAFLD.

Derivation and Validation of a Model to Predict Clinically Significant Portal Hypertension Using Transient Elastography and FIB-4

BACKGROUND

Liver biopsy and hepatic venous pressure gradient (HVPG), the gold standard for assessing advanced fibrosis (AF) and clinically significant portal hypertension (CSPH), are invasive, costly, and time-consuming.

GOAL

We investigated if the combination of fibrosis index based on 4 factors (FIB-4) and liver stiffness measure (LSM) can identify AF and more importantly, CSPH.

PATIENTS AND METHODS

Patients with chronic liver disease referred for transjugular liver biopsy were analyzed retrospectively. FIB-4 and LSM were compared with liver histology for diagnosing AF. FIB-4, LSM, and platelet count were compared with HVPG for diagnosing CSPH. Optimal cutoffs for predicting CSPH were determined by grid search. A composite log-odds to predict CSPH was derived from logistic regression using LSM, FIB-4, and gender. Internal bootstrap validation and external validation were performed.

RESULTS

A total of 142 patients were included in the derivation; 42.3% had AF, and 11.3% had CSPH using the current gold standards. The area under the receiver operating characteristic curve (AUROC) for LSM, FIB-4, and their combination to predict AF were 0.7550, 0.7049, and 0.7768, respectively. LSM, FIB-4, and platelet count predicted CSPH with AUROC 0.6818, 0.7532, and 0.7240, respectively. LSM plus FIB-4 showed the best performance in predicting CSPH with AUROC 0.8155. Based on LSM, FIB-4, and gender, a novel model-the Portal Hypertension Assessment Tool (PHAT)-was developed to predict CSPH. PHAT score ≥-2.76 predicted CSPH with sensitivity 94%, specificity 67%, positive predictive value 27%, negative predictive value 99%, and accuracy 70%. In internal and external validation, AUROCs for the model were 0.8293 and 0.7899, respectively.

CONCLUSION

A model consisting of FIB-4, LSM, and gender can identify CSPH among patients with chronic liver disease.

Impairment of patient-reported outcomes among patients with non-alcoholic fatty liver disease: a registry-based study

BACKGROUND

Patients with non-alcoholic fatty liver disease (NAFLD) and more advanced fibrosis tend to have more impairment in their health-related quality of life and other patient-reported outcomes (PROs).

AIM

To assess the association of PROs with select non-invasive tests (NITs) for fibrosis including FAST, Agile 3+ and Agile 4 scores METHODS: We enrolled patients with an established diagnosis of NAFLD who were seen in a tertiary care clinic into the NAFLD/NASH Registry. The FAST, Agile 3+ and Agile 4 scores were calculated using liver stiffness measurements by transient elastography and laboratory parameters. PROs were assessed using FACIT-F, CLDQ-NASH and WPAI instruments (total of 17 domain and summary scores).

RESULTS

There were 1509 patients with NAFLD (mean age: 49 ± 11 years, 50% men, 41% employed, 30% advanced fibrosis and 20% cirrhosis). The mean FAST, Agile 3+ and Agile 4 scores were 0.39 ± 0.26, 0.35 ± 0.31 and 0.12 ± 0.23, respectively. Subjects with lower FAST, Agile 3+ and Agile 4 scores had the highest scores in select domains of FACIT-F, CLDQ-NASH and WPAI (p < 0.05 in comparison to subjects with elevated or high-risk NIT scores). Correlations with continuous NITs were significantly negative for Emotional and Functional well-being (FACIT-F), Activity/energy, Systemic symptoms, Worry and total scores (CLDQ-NASH), and Activity of WPAI (p < 0.05); the strongest was for Worry (CLDQ-NASH) with FAST (R = -0.17, p < 0.0001). The PRO scores of patients with NAFLD were lower than those of matched patients with chronic hepatitis B (p < 0.05 for 9/17 domain and summary scores).

CONCLUSION

Patients with NAFLD and high FAST, Agile 3+ or Agile 4 scores experience impairment of health-related quality of life.

Vitamin D-Related Genetic Variations and Nonalcoholic Fatty Liver Disease: A Systematic Review

Background: Studies have demonstrated the link between vitamin-D-related genetic variations and nonskeletal outcomes. We aimed to identify all available data on the association of vitamin-D-related genetic variations with nonalcoholic fatty liver disease (NAFLD). Methods: Potentially eligible studies were identified from Embase and Medline databases from inception to June 2022 using a search strategy that comprised terms for “Vitamin D” and “NAFLD”. Eligible studies must report the association between vitamin D-related genetic variations and presence, severity or response to treatment of NAFLD. Data were extracted from each eligible study. Results: A total of 3495 articles were identified. After a systematic review, twelve studies were included. A total of 26 genetic variations were identified. Presence of NAFLD was associated with variations of GC (rs222054, rs222020, rs10011000, rs7041), VDR (rs2228570, rs11168287, rs10783219, rs4752), CYP24A1 (rs3787557, rs6068816, rs2296241, rs2248359) and CYP27B1 (rs4646536). Severity of NAFLD was associated with variations of GC (rs4588), VDR (rs2228570, rs4334089), CYP2R1 (rs10741657), DHCR7 (rs1544410, rs3829251, rs12785878) and CYP24A1 (rs3787557, rs6068816, rs6097809, rs6127119, rs2248359, rs3787554, rs4809960, rs6022999). Response to calcitriol treatment was associated with variation of VDR (rs10735810). Conclusions: Multiple vitamin D-related genetic variations were associated with NAFLD, indicating the role of vitamin D in the pathogenesis of NAFLD.

The Economic Burden of Non-Alcoholic Steatohepatitis: A Systematic Review

BACKGROUND

The global prevalence of non-alcoholic steatohepatitis (NASH) is increasing, such that NASH is predicted to become the leading cause of liver transplantation (LT) in the US by 2025. Despite this, data on the economic burden of NASH are limited.

OBJECTIVES

This systematic literature review aimed to summarise and critically evaluate studies reporting on the economic burden of NASH and identify evidence gaps for subsequent research.

METHODS

Medline, EMBASE, the Cochrane Library and EconLit were searched up to 6 January 2021 for English language articles published from January 2010 to January 2021 inclusive that reported economic outcomes of a NASH population or subpopulation. Evidence was presented and synthesised using narrative data analysis, and quality was assessed by two reviewers using an 11-item checklist developed for economic evaluations and adapted to cost of illness.

RESULTS

Fourteen studies were included, of which five presented data on costs and resource use, four on costs only and five on resource use only. Overall, NASH is associated with a significant and increasing economic burden in terms of healthcare resource utilisation (HCRU) and direct and indirect costs. This burden was higher among NASH patients with advanced (fibrosis stage 3-4) versus early (fibrosis stage 0-2) disease, symptomatic versus asymptomatic disease and for patients with complications or comorbidities versus those without. In LT patients, those with NASH as the primary indication had greater HCRU and higher costs compared with non-NASH indications such as hepatitis B and C viruses. Considerable variability in HCRU and costs was seen across the US and Europe, with the highest costs seen in the US. The quality of the included studies was variable, and the studies themselves were heterogeneous in terms of study methodology, patient populations, comorbidities, follow-up time and outcomes measured.

CONCLUSIONS

This review highlights a general scarcity of NASH-specific economic outcomes data. Despite this, the identified studies show that NASH is associated with a significant economic burden in terms of increased HCRU, and high direct medical and non-medical costs and societal burden that increases with disease severity or when patients have complications or comorbidity. More national-level NASH prevalence data are needed to generate accurate forecasts of HCRU and costs in the coming decades.

FUNDING

Novo Nordisk A/S, Søborg, Denmark.

Label-free metabolic imaging of non-alcoholic-fatty-liver-disease (NAFLD) liver by volumetric dynamic optical coherence tomography

Label-free metabolic imaging of non-alcoholic fatty liver disease (NAFLD) mouse liver is demonstrated ex vivo by dynamic optical coherence tomography (OCT). The NAFLD mouse is a methionine choline-deficient (MCD)-diet model, and two mice fed the MCD diet for 1 and 2 weeks are involved in addition to a normal-diet mouse. The dynamic OCT is based on repeating raster scan and logarithmic intensity variance (LIV) analysis that enables volumetric metabolic imaging with a standard-speed (50,000 A-lines/s) OCT system. Metabolic domains associated with lipid droplet accumulation and inflammation are clearly visualized three-dimensionally. Particularly, the normal-diet liver exhibits highly metabolic vessel-like structures of peri-vascular hepatic zones. The 1-week MCD-diet liver shows ring-shaped highly metabolic structures formed with lipid droplets. The 2-week MCD-diet liver exhibits fragmented vessel-like structures associated with inflammation. These results imply that volumetric LIV imaging is useful for visualizing and assessing NAFLD abnormalities.

The mitochondrial pyruvate carrier at the crossroads of intermediary metabolism

Pyruvate metabolism, a central nexus of carbon homeostasis, is an evolutionarily conserved process and aberrant pyruvate metabolism is associated with and contributes to numerous human metabolic disorders including diabetes, cancer, and heart disease. As a product of glycolysis, pyruvate is primarily generated in the cytosol before being transported into the mitochondrion for further metabolism. Pyruvate entry into the mitochondrial matrix is a critical step for efficient generation of reducing equivalents and ATP and for the biosynthesis of glucose, fatty acids, and amino acids from pyruvate. However, for many years, the identity of the carrier protein(s) that transported pyruvate into the mitochondrial matrix remained a mystery. In 2012, the molecular-genetic identification of the mitochondrial pyruvate carrier (MPC), a heterodimeric complex composed of protein subunits MPC1 and MPC2, enabled studies that shed light on the many metabolic and physiological processes regulated by pyruvate metabolism. A better understanding of the mechanisms regulating pyruvate transport and the processes affected by pyruvate metabolism may enable novel therapeutics to modulate mitochondrial pyruvate flux to treat a variety of disorders. Herein, we review our current knowledge of the MPC, discuss recent advances in the understanding of mitochondrial pyruvate metabolism in various tissue and cell types, and address some of the outstanding questions relevant to this field.

Nonalcoholic Steatohepatitis (NASH) and Atherosclerosis: Explaining Their Pathophysiology, Association and the Role of Incretin-Based Drugs

Nonalcoholic steatohepatitis (NASH) is the most severe manifestation of nonalcoholic fatty liver disease (NAFLD), a common complication of type 2 diabetes, and may lead to cirrhosis and hepatocellular carcinoma. Oxidative stress and liver cell damage are the major triggers of the severe hepatic inflammation that characterizes NASH, which is highly correlated with atherosclerosis and coronary artery disease. Regarding drug therapy, research on the role of GLP-1 analogues and DPP4 inhibitors, novel classes of antidiabetic drugs, is growing. In this review, we outline the association between NASH and atherosclerosis, the underlying molecular mechanisms, and the effects of incretin-based drugs, especially GLP-1 RAs, for the therapeutic management of these conditions.

Empagliflozin Improves Liver Steatosis and Fibrosis in Patients with Non-Alcoholic Fatty Liver Disease and Type 2 Diabetes: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

INTRODUCTION

To evaluate the efficacy of empagliflozin compared to pioglitazone in patients with non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes (T2DM).

METHODS

In this prospective randomized, double-blind, placebo-controlled trial, we assigned 106 patients with NAFLD and T2DM to receive empagliflozin 10 mg (n = 35), pioglitazone 30 mg (n = 34), or placebo (n = 37) for 24 weeks. Liver fat content and liver stiffness were measured using fibroscans. Body composition assessment was performed by dual-energy x-ray absorptiometry (DEXA) scans. The primary end point was change from baseline in liver steatosis, using the controlled attenuation parameter (CAP) score.

RESULTS

A borderline significant decrease in CAP score was observed with empagliflozin compared to placebo, mean difference: - 29.6 dB/m (- 39.5 to - 19.6) versus - 16.4 dB/m (- 25.0 to - 7.8), respectively; p = 0.05. Using multivariate analysis, we observed a significant reduction in the placebo-corrected change in liver stiffness measurement (LSM) with empagliflozin compared to pioglitazone: - 0.77 kPa (- 1.45, - 0.09), p  = 0.02, versus 0.01 kPa (95% CI - 0.70, 0.71, p  = 0.98), p for comparison = 0.03. Changes in serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT), fasting insulin, homeostatic model assessment for insulin resistance (HOMA-IR), HOMA2-IR, fibrosis-4 index (FIB4 index), NAFLD fibrosis score, aspartate aminotransferase to platelet ratio index (APRI), android/gynecoid ratio (A/G ratio), and skeletal muscle index (SMI) were comparable between the two treatment groups, while significant reductions of the body weight and visceral fat area were observed only in the empagliflozin group (p  < 0.001 and p  = 0.01, respectively) and both were increased in the placebo and pioglitazone groups. There were no serious adverse events in either group.

CONCLUSION

Treatment for 24 weeks with empagliflozin, in contrast to pioglitazone, was associated with improvement of liver steatosis and fibrosis in patients with NAFLD and T2DM. In addition, body weight and abdominal fat area were decreased in the empagliflozin group.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials (IRCT), IRCT20190122042450N3.

Evaluating the Efficacy of Carum Copticum Seeds on the Treatment of Patients with Nonalcoholic Fatty Liver Disease: A Multi-Center, Randomized, Triple–Blind, Placebo-Controlled Clinical Trial Study

Background: The increased prevalence of Nonalcoholic Fatty Liver Disease (NAFLD) has caused several concerns. Besides, there are concerns about the side effects of the drugs used to treat this condition. Since the current treatments are not effective in treating NAFLD, developing a novel therapeutic option based on some medicinal plants is necessary. Few studies have investigated the natural drugs and their effects (e.g., extracts of Carum Copticum Seeds (CCS)) on these patients. Objectives: The current study intended to evaluate the safety and efficacy of CCS extracts on liver enzymes, serum lipids, as well as the grade of fatty liver, and anthropometric measurements in patients with nonalcoholic fatty liver disease. Methods: In this multi-center, randomized, triple-blind, placebo-controlled clinical trial study, 90 patients with grades of 1 to 3 of nonalcoholic fatty liver disease referred to two medical centers located in Tehran (Iran) in 2019 are examined. Diet and exercise were recommended for patients three times a day in eight weeks, in addition to taking 500 mg capsules (aqueous extracts of Ajwain seeds and placebo for treatment and placebo groups). Results: Medical records of 68 patients were reviewed, 48 (71%) male and 20 (29%) female. Both groups were similar concerning demographic and baseline characteristics. The total score of the Leeds questionnaire [-14.03 vs. -7.49, P = 0.048], Triglyceride (TG) [-4.45 vs. 10.03, P = 0.017], and Alanine Aminotransferase (ALT) [-14.71 vs. -4.79, P = 0.012] were significantly changed in the treatment group compared to the control group. Nevertheless, a different situation was observed for Aspartate Aminotransferase (AST) [-7.08 vs. -4.84, P = 0.314], Fasting Blood Sugar (FBS) [-2.88 vs. -2.81, P = 0.207], and Body Mass Index (BMI) [-0.59 vs. -0.39, P = 0.095]. Although a significant change was found in both groups, the amount of decline was similar for both groups. In both groups, the cholesterol, High-Density Lipoprotein (HDL), and Low-Density Lipoprotein (LDL) did not change significantly. The sonographic findings indicated significantly higher improvements in the intervention group than the placebo group (RR = 2.43, 95% CI (1.15-5.65), and P value = 0.034). Conclusions: The result of this study supports the efficacy of Carum copticum seeds in the treatment of nonalcoholic fatty liver disease patients. It was found that CCS with a significant reduction in ALT, TG, and relative reduction of BMI can help physicians to manage other metabolic disorders associated with NAFLD, such as obesity and hyperlipidemia.

Efficacy of combining pentoxiphylline and vitamin E versus vitamin E alone in non-alcoholic steatohepatitis- A randomized pilot study

BACKGROUND AND AIM

Non-alcoholic steatohepatitis (NASH) is the most prevalent cause of chronic liver disease. Vitamin E (VE), an anti-oxidant, has shown improvement in NAFLD activity score (NAS) but not fibrosis. Pentoxiphylline (PTX), an anti-TNF-alpha agent, has been reported to reduce hepatic inflammation and fibrosis. We evaluated combination of these drugs in NASH patients.

METHODS

In a prospective study, consecutive histologically proven patients with NASH were randomized to receive either PTX, 400 mg thrice daily and VE 400 IU twice daily (group PTVE, n = 36) or VE alone (group VE, n = 33). Clinical, dietary and biochemical follow-up was done till 12 months. Primary end-point was change in alanine aminotransferase (ALT)  levels.   RESULTS: Both groups were comparable at baseline. On a strict diet and lifestyle modification regimen, both groups had similar reduction in body mass index and waist circumference. There was a similar reduction in ALT levels in the two groups. Metabolically, patients in PTVE group had greater reduction in fasting insulin levels and homeostatic model assessment of insulin resistance (HOMA-IR) than VE group (p = 0.05). Tumor necrosis factor alpha (TNFα) levels were also significantly lower in PTVE group from 6 months onwards. Twelve (10%) patients had repeat liver biopsy (7 in group PTVE, 5 in group VE) with no difference in reduction of NAS score (p = 0.45). However, there was a significant fibrosis regression in PTVE compared to VE group (p = 0.003).

CONCLUSIONS

These data show greater efficacy of a combination of PTX and VE in achieving fibrosis regression compared to VE alone with better metabolic homeostasis and amelioration of the pro-inflammatory status.

TRIAL REGISTRATION

Clinical Trials Registry no. NCT01384578.

NAFLD-related HCC

Nonalcoholic fatty liver disease (NAFLD) is one of the major drivers for the rising trend in hepatocellular carcinoma (HCC). Over the past three decades, the incidence of both NAFLD and HCC have increased two- to threefold. It has been forecasted that the number of patients with NAFLD in the Unites States will reach 101 million by 2030; global increase is also foreseen. This trend will likely continue to translate into increased HCC in the Unites States and across the globe. In this chapter, we summarize the current evidence linking NAFLD, metabolic syndrome, particularly obesity and type 2 diabetes mellitus, and HCC. We describe the main molecular mechanisms connecting these metabolic perturbations and hepatocarcinogenesis.

Effect of Empagliflozin on Liver Steatosis and Fibrosis in Patients With Non-Alcoholic Fatty Liver Disease Without Diabetes: A Randomized, Double-Blind, Placebo-Controlled Trial

Introduction

Despite the high prevalence of non-alcoholic fatty liver disease (NAFLD) and its associated co-morbidities, no efficient treatment in a high percentage of individuals is available. Beneficial effects of sodium–glucose co-transporter 2 inhibitors on fatty liver have been investigated in people with type 2 diabetes (T2DM). The aim of this study was to explore the effect of empagliflozin on liver steatosis and fibrosis in patients with NAFLD without T2DM.

Methods

In this prospective randomized, double-blind, placebo-controlled clinical trial, participants with NAFLD were randomized to empagliflozin (10 mg/day) (n = 43) or placebo (n = 47) for 24 weeks. Hepatic steatosis and fibrosis were assessed using transient elastography to measure the controlled attenuation parameter (CAP) and liver stiffness measurement (LSM). The primary outcome was the change in CAP score at 24 weeks.

Results

There was significant decrease in CAP score in both groups but no significant difference was observed between the two groups (P = 0.396). LSM was significantly decreased in the empagliflozin-treated group (6.03 ± 1.40 to 5.33 ± 1.08 kPa; P = 0.001), while no change was found in the placebo group. In subgroups analysis of patients with significant steatosis at baseline (CAP ≥ 302 dB/m), steatosis significantly improved in the empagliflozin group (37.2% vs. 17%; P = 0.035). There was a significant decrease in the grade of liver fat on visual analysis of ultrasound images, AST, ALT, and fasting insulin levels in the empagliflozin group, while no changes were observed in the placebo group.

Conclusions

Empagliflozin improves liver steatosis and, more importantly, measures of liver fibrosis in patients with NAFLD without T2DM.

Trial registration

ClinicalTrials.gov identifier, IRCT20190122042450N1.

The Protective Effect of Cynara Cardunculus Extract in Diet-Induced NAFLD: Involvement of OCTN1 and OCTN2 Transporter Subfamily

Hyperlipidemia and insulin-resistance are often associated with Non-Alcoholic Fatty Liver Disease (NAFLD) thereby representing a true issue worldwide due to increased risk of developing cardiovascular and systemic disorders. Although clear evidence suggests that circulating fatty acids contribute to pathophysiological mechanisms underlying NAFLD and hyperlipidemia, further studies are required to better identify potential beneficial approaches for counteracting such a disease. Recently, several artichoke extracts have been used for both reducing hyperlipidemia, insulin-resistance and NAFLD, though the mechanism is unclear. Here we used a wild type of Cynara Cardunculus extract (CyC), rich in sesquiterpens and antioxidant active ingredients, in rats fed a High Fat Diet (HFD) compared to a Normal Fat Diet (NFD). In particular, in rats fed HFD for four consecutive weeks, we found a significant increase of serum cholesterol, triglyceride and serum glucose. This effect was accompanied by increased body weight and by histopathological features of liver steatosis. The alterations of metabolic parameters found in HFDs were antagonised dose-dependently by daily oral supplementation of rats with CyC 10 and 20 mg/kg over four weeks, an effect associated to significant improvement of liver steatosis. The effect of CyC (20 mg/kg) was also associated to enhanced expression of both OCTN1 and OCTN2 carnitine-linked transporters. Thus, present data suggest a contribution of carnitine system in the protective effect of CyC in diet-induced hyperlipidemia, insulin-resistance and NAFLD.

Atorvastatin and Vitamin E Accelerates NASH Resolution by Dietary Intervention in a Preclinical Guinea Pig Model

Despite affecting millions of patients worldwide, no pharmacological treatment has yet proved effective against non-alcoholic steatohepatitis (NASH) induced liver fibrosis. Current guidelines recommend lifestyle modifications including reductions in dietary energy intake. Recently, therapy with atorvastatin and vitamin E (vitE) has been recommended, although clinical studies on the resolution of hepatic fibrosis are inconclusive. Targeting NASH-induced hepatic end-points, this study evaluated the effects of atorvastatin and vitE alone or in combination with a dietary intervention in the guinea pig NASH model. Guinea pigs (n = 72) received 20 weeks of high fat feeding before allocating to four groups: continued HF feeding (HF), HF diet with atorvastatin and vitE (HF+), low-fat diet (LF) and low-fat with atorvastatin and vitE (LF+), for four or eight weeks of intervention. Both LF and LF+ decreased liver weight, cholesterol and plasma dyslipidemia. LF+ further improved hepatic histopathological hallmarks (p < 0.05), liver injury markers aspartate aminotransferase (AST) and alanine aminotransferase (ALT) (p < 0.05) and reduced the expression of target genes of hepatic inflammation and fibrosis (p < 0.05), underlining an increased effect on NASH resolution in this group. Collectively, the data support an overall beneficial effect of diet change, and indicate that atorvastatin and vitE therapy combined with a diet change act synergistically in improving NASH-induced endpoints.

Fermented black radish (Raphanus sativus L. var. niger) attenuates methionine and choline deficient diet-induced nonalcoholic fatty liver disease in mice

As one of the wide-ranging form of chronic liver disease, there are only limited therapeutic options for nonalcoholic fatty liver disease (NAFLD). We evaluated whether fermented black radish (Raphanus sativus L. var. niger; FBR) ameliorates lipid accumulation, inflammation, and hepatic fibrosis, which are characteristics of the pathogenesis of NAFLD. Fermented black radish treatment reduced lipid accumulation in 3T3-L1 adipocytes, which appeared to be associated with the downregulation of adipogenic transcription factors, including sterol regulatory element-binding protein 1c, CCAAT/enhancer-binding protein α, peroxisome proliferator-activated receptor γ, and lipid accumulation-related genes including adipocyte protein-2 and fatty acid synthase. Administration of FBR to C57BL/6J mice challenged with methionine and choline deficient (MCD) diet significantly attenuated the increased serum levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and triglyceride. In addition, treatment with FBR interestingly repressed the hepatic inflammation induced with MCD diet, by lowering the expression of inducible nitric oxide synthase and suppressing the inactivation of macrophages and Kupffer cells in the liver. Fermented black radish was also shown to mitigate liver fibrosis through the inhibition of alpha-smooth muscle actin, transforming growth factor beta-1, and collagen type I alpha 1 chain. Our results indicate that FBR ameliorates NAFLD and its related metabolic disease by regulating multiple pathways, suggesting that FBR may be an effective dietary supplement for ameliorating NAFLD.

Inhibition of TREM-1 attenuates inflammation and lipid accumulation in diet-induced nonalcoholic fatty liver disease

In the liver tissues of obese diabetic or nondiabetic patients, triggering receptor expressed on myeloid cells-1 (TREM-1) is usually found to be upregulated, thus leading to upregulation of various inflammatory cytokines and lipid accumulation. On the other hand, nonalcoholic fatty liver disease (NAFLD), characterized by excess lipid accumulation, and inflammatory injury in liver, is becoming an epidemic disease, globally. In the present study, we aimed to investigate the biological role and the underlying mechanisms of TREM-1 in NAFLD. upregulation of TREM-1 occurred in high-fat diet (HFD)-induced mice NAFLD model and oleic acid-treated HepG2 and primary mouse hepatocytes cell model at messenger RNA and protein levels. Functional studies established that overexpression of TREM-1 displayed hyperlipidemia, and increased in inflammatory indicators and lipid accumulation-related genes, which was ameliorated by knockdown of TREM-1. Our results also showed that obvious lipid accumulation and inflammatory injury occurred in the liver tissue of HFD-fed mice, while treatment with lentiviral vector short hairpin TREM showed marked improvement in tissue morphology and architecture and less lipid accumulation, thus deciphering the mechanism through which knockdown of TREM-1 ameliorated the inflammatory response and lipid accumulation of NAFLD mice through inactivation of the nuclear factor-κB (NF-κB) and PI3K/AKT signal pathways, respectively. In conclusion, TREM-1/NF-κB and TREM-1/PI3K/AKT axis could be an important mechanism in ameliorating the inflammatory response and lipid accumulation, respectively, thus shedding light on the development of novel therapeutics to the treatment of NAFLD.

Haptoglobin 2 Allele is Associated With Histologic Response to Vitamin E in Subjects With Nonalcoholic Steatohepatitis

BACKGROUND

Haptoglobin (Hp) genotype has been linked to oxidative stress and cardiovascular outcomes in response to vitamin E (VitE) among patients with diabetes mellitus. Its effect on histologic response to VitE in nonalcoholic steatohepatitis (NASH) is unknown.

GOALS

Our objective was to determine if Hp genotype associates with response to VitE in patients with NASH.

STUDY

A post hoc analysis of 228 patients receiving VitE or placebo in 2 clinical trials was performed. Regression analysis was used to assess the effect of VitE versus placebo, by Hp genotype (1-1, 2-1, or 2-2), on histologic features and laboratory markers of nonalcoholic fatty liver disease, comparing baseline to end of treatment values. An interaction term was included in the regression models to assess differential treatment effect across Hp genotype.

RESULTS

Hp 2-2 patients treated with VitE versus placebo showed significant histologic improvement (51% vs. 20%; OR=4.2; P=0.006), resolution of steatohepatitis (44% vs. 12%; OR=6.2; P=0.009), decrease in nonalcoholic fatty liver disease Activity Score (NAS) (-2.2 vs. -0.6; P=0.001), and decrease in liver enzymes alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and γ-glutamyl transpeptidase. Hp 2-1 patients on VitE versus placebo showed improved resolution of steatohepatitis, NAS and liver enzymes. Hp 1-1 patients showed no significant improvement in histology or liver enzymes. VitE had no effect on fibrosis stage in any group. Regression analysis showed incremental benefit of having Hp 2-2 or 2-1 versus 1-1 for all liver enzyme.

CONCLUSIONS

Hp 2 allele is associated with greater histologic and biological improvement in NASH with VitE treatment compared with the Hp 1 allele.

Pathogenesis of NASH: The Impact of Multiple Pathways

Purpose of review

Advancing our understanding of the mechanisms that underlie NASH pathogenesis.

Recent findings

Recent findings on NASH pathogenesis have expanded our understanding of its complexity including: (1) there are multiple parallel hits that lead to NASH; (2) the microbiota play an important role in pathogenesis, with bacterial species recently shown to accurately differentiate between NAFL and NASH patients; (3) the main drivers of liver cell injury are lipotoxicity caused by free fatty acids (FFAs) and their derivatives combined with mitochondrial dysfunction; (4) decreased endoplasmic reticulum (ER) efficiency with increased demand for protein synthesis/folding/repair results in ER stress, protracted unfolded protein response, and apoptosis; (5) upregulated proteins involved in multiple pathways including JNK, CHOP, PERK, BH3-only proteins, and caspases result in mitochondrial dysfunction and apoptosis; and (6) subtypes of NASH in which these pathophysiological pathways vary may require patient subtype identification to choose effective therapy.

Summary

Recent pathogenesis studies may lead to important therapeutic advances, already seen in patients treated with ACC, ASK1 and SCD1 inhibitors and FXR agonists. Further advancing our understanding of mechanisms underlying NASH pathogenesis and the complex interplay between them will be crucial for developing effective therapies.

Modeling the Western Diet for Preclinical Investigations

Rodent models have been invaluable for biomedical research. Preclinical investigations with rodents allow researchers to investigate diseases by using study designs that are not suitable for human subjects. The primary criticism of preclinical animal models is that results are not always translatable to humans. Some of this lack of translation is due to inherent differences between species. However, rodent models have been refined over time, and translatability to humans has improved. Transgenic animals have greatly aided our understanding of interactions between genes and disease and have narrowed the translation gap between humans and model animals. Despite the technological innovations of animal models through advances in genetics, relatively little attention has been given to animal diets. Namely, developing diets that replicate what humans eat will help make animal models more relevant to human populations. This review focuses on commonly used rodent diets that are used to emulate the Western dietary pattern in preclinical studies of obesity and type 2 diabetes, nonalcoholic liver disease, maternal nutrition, and colorectal cancer.

Current and future pharmacologic treatment of nonalcoholic steatohepatitis

PURPOSE OF REVIEW

Nonalcoholic steatohepatitis (NASH), the aggressive form of nonalcoholic fatty liver disease (NAFLD), can progress to cirrhosis and hepatocellular cancer in 5-15% of patients and is rapidly becoming the leading cause for end-stage liver disease. Dietary caloric restriction and exercise, currently the cornerstone of therapy for NAFLD, can be difficult to achieve and maintain, underscoring the dire need for pharmacotherapy. This review presents the agents currently used in managing NAFLD and their pharmacologic targets. It also provides an overview of NAFLD agents currently under development.

RECENT FINDINGS

Therapies for NASH can be broadly classified into agents that target the metabolic perturbations driving disease pathogenesis (such as insulin resistance and de novo lipogenesis) and agents that target downstream processes including cell stress, apoptosis, inflammation, and fibrosis. Modulation of peroxisome proliferator-activator receptors, farnesoid-X-receptors, and the glucagon-like peptide 1 pathway have been shown to improve liver histology. The intestinal microbiome and metabolic endotoxemia are novel targets that are currently under review. Antioxidants such as vitamin E, and more recently anti-inflammatory agents such as apoptosis signal-regulating kinase 1 inhibitors show promise as therapy for NASH. Several antifibrotic agents including cysteine-cysteine motif chemokine receptor type 2 and type 5 antagonists have been shown to inhibit the progression of fibrosis toward cirrhosis.

SUMMARY

There are currently several agents in the drug pipeline for NASH. Within the next few years, the availability of therapeutic options for NAFLD will hopefully curb the rising trend of NAFLD-related end stage liver disease.