Global Epidemiology of Nonalcoholic Fatty Liver Disease and Perspectives on US Minority Populations

Inhibition of MLKL Attenuates Necroptotic Cell Death in a Murine Cell Model of Ischaemia Injury

BACKGROUND

Steatosis in donor livers poses a major risk of organ dysfunction due to their susceptibility to ischaemia-reperfusion (I/R) injury during transplant. Necroptosis, a novel form of programmed cell death, is orchestrated by receptor-interacting protein kinase 1 (RIPK1), receptor-interacting protein kinase 3 (RIPK3) and mixed-lineage kinase domain-like pseudokinase (MLKL), has been implicated in I/R injury. Here we investigated the mechanisms of cell death pathways in an in vitro model of hepato-steatotic ischaemia.

METHODS

Free fatty acid (FFA) treated alpha mouse liver 12 (AML-12) cells were incubated in oxygen-glucose-deprivation (OGD) conditions as seen during ischaemia.

RESULTS

We found that OGD triggered upregulation of insoluble fraction of RIPK3 and MLKL in FFA + OGD cells compared to FFA control cells. We report that intervention with small interfering (si) MLKL and siRIPK3 significantly attenuated cell death in FFA + OGD cells. Absence of activated CASPASE8 and cleaved-CASPASE3, no change in the expression of CASPASE1 and prostaglandin-endoperoxide synthase 2 (Ptgs2) in FFA + OGD treated cells compared to FFA control cells indicated that apoptosis, pyroptosis and ferroptosis, respectively, are unlikely to be active in this model.

CONCLUSION

Our findings indicate that RIPK3-MLKL dependent necroptosis contributed to cell death in our in vitro model. Both MLKL and RIPK3 are promising therapeutic targets to inhibit necroptosis during ischaemic injury in fatty liver.

Pharmacological activation of REV-ERBα improves nonalcoholic steatohepatitis by regulating intestinal permeability

BACKGROUND AND OBJECTIVES

The gut-liver axis plays an important role in the pathogenesis of nonalcoholic steatohepatitis (NASH), and increased intestinal permeability causes transfer of endotoxin to the liver, which activates the immune response, ultimately leading to hepatic inflammation. Nuclear receptor Rev-erbα is a critical regulator of circadian rhythm, cellular metabolism, and inflammatory responses. However, the role and mechanism of Rev-erbα in gut barrier function and NASH remain unclear. In the present study, we investigated the involvement of Rev-erbα in the regulation of intestinal permeability and the treatment of NASH.

METHODS AND RESULTS

The expression of tight junction-related genes and Rev-erbs decreased in the jejunum, ileum and colon of mice with high cholesterol, high fat diet (CL)-induced NASH. Chromatin immunoprecipitation analysis indicated that REV-ERBα directly bound to the promoters of tight junction genes to regulate intestinal permeability. Pharmacological activation of REV-ERBα by SR9009 protected against lipopolysaccharide-induced increased intestinal permeability both in vitro and in vivo, and these effects were associated with the activation of autophagy and decreased apoptotic signaling of epithelial cells. In addition, the chronopharmacological effects of SR9009 were more potent at Zeitgeber time 0 (ZT0) than at ZT12, which was contrary to the rhythm of Rev-erbs in the gastrointestinal tract. The administration of SR9009 attenuated hepatic lipid accumulation, insulin resistance, inflammation, and fibrosis in mice with CL diet-induced NASH, which might be partly attributed to the enhancement of intestinal barrier function.

CONCLUSION

Chronopharmacological activation of REV-ERBα might be a potential strategy to treat intestinal barrier dysfunction-related disorders and NASH.

The Natural History of NAFLD, a Community-Based Study at a Large Health Care Delivery System in the United States

Nonalcoholic fatty liver disease (NAFLD) is a global public health problem. However, the natural history of NAFLD is incomplete. This is a retrospective cohort study of patients identified with NAFLD by diagnosis codes in a large, community-based health care delivery system. The objectives were (1) to follow patients from initial NAFLD presentation through progression to cirrhosis and/or decompensated cirrhosis to liver cancer, liver transplant, and death for up to 10 years; and (2) to conduct disease progression analysis restricted to patients with NAFLD identified as having diabetes at baseline. A total of 98,164 patients with full NAFLD and 26,488 with diabetes were divided into three baseline prevalent states: (1) no cirrhosis, (2) compensated cirrhosis, and (3) decompensated cirrhosis. In baseline patients without cirrhosis, annual rates of compensated cirrhosis, decompensated cirrhosis, and death were 0.28%, 0.31%, and 0.63% per year, respectively. With baseline compensated cirrhosis, the annual rates of decompensation and death were 2.4% and 6.7% per year. Finally, in those with decompensated cirrhosis at baseline, the death rate was 8.0% per year. In those without cirrhosis and with cirrhosis at baseline, the rates of liver cancer and death were increased approximately 2-fold in the diabetic subpopulation compared with the full NAFLD cohort. Age and comorbidities increased with increasing disease severity. Cox proportional hazards regression analysis showed that cirrhosis was strongly associated with death and liver cancer, and that diabetes was associated with a significant increase in the hazard of both liver cancer and death (2.56 [2.04-3.20] and 1.43 [1.35-1.52]), respectively. Conclusion: The findings of this community-based study further our understanding of the natural history of NAFLD and demonstrate that diabetes is a major factor in the progression of this disease.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

N-Acetyl Cysteine Targets Hepatic Lipid Accumulation to Curb Oxidative Stress and Inflammation in NAFLD: A Comprehensive Analysis of the Literature

Impaired adipose tissue function and insulin resistance remain instrumental in promoting hepatic lipid accumulation in conditions of metabolic syndrome. In fact, enhanced lipid accumulation together with oxidative stress and an abnormal inflammatory response underpin the development and severity of non-alcoholic fatty liver disease (NAFLD). There are currently no specific protective drugs against NAFLD, and effective interventions involving regular exercise and healthy diets have proved difficult to achieve and maintain. Alternatively, due to its antioxidant and anti-inflammatory properties, there has been growing interest in understanding the therapeutic effects of N-acetyl cysteine (NAC) against metabolic complications, including NAFLD. Here, reviewed evidence suggests that NAC blocks hepatic lipid accumulation in preclinical models of NAFLD. This is in part through the effective regulation of a fatty acid scavenger molecule (CD36) and transcriptional factors such as sterol regulatory element-binding protein (SREBP)-1c/-2 and peroxisome proliferator-activated receptor gamma (PPARγ). Importantly, NAC appears effective in improving liver function by reducing pro-inflammatory markers such as interleukin (IL)-6 IL-1β, tumour necrosis factor alpha (TNF-α) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). This was primarily through the attenuation of lipid peroxidation and enhancements in intracellular response antioxidants, particularly glutathione. Very few clinical studies support the beneficial effects of NAC against NAFLD-related complications, thus well-organized randomized clinical trials are still necessary to confirm its therapeutic potential.

CML/RAGE Signal Bridges a Common Pathogenesis Between Atherosclerosis and Non-alcoholic Fatty Liver

Non-alcoholic fatty liver disease (NAFLD) has become a common chronic disease in the world. NAFLD is not only a simple intrahepatic lesion, but also affects the occurrence of a variety of extrahepatic complications. In particular, cardiovascular complications are particularly serious, which is the main cause of death in patients with NAFLD. To study the relationship between NAFLD and AS may be a new way to improve the quality of life in patients with NAFLD. As we all known, inflammatory response plays an important role in the occurrence and development of NAFLD and AS. In this study, we found that the accumulation of Nε-carboxymethyllysine (CML) in the liver leads to hepatic steatosis. CML can induce the expression of interleukin (IL-1β), interleukin (IL-6), tumor necrosis factor (TNF-α), C-reactionprotein (CRP) by binding with advanced glycosylation end-product receptor (RAGE) and accelerate the development of AS. After silencing RAGE expression, the expression of pro-inflammatory cytokines was inhibited and liver and aorta pathological changes were relieved. In conclusion, CML/RAGE signal promotes the progression of non-alcoholic fatty liver disease and atherosclerosis. We hope to provide new ideas for the study of liver vascular dialogue in multi organ communication.

Diseases with health disparities as drivers of COVID-19 outcome

The COVID-19 pandemic has forced our society to come face to face with complex issues that were once theoretical but are now being played out in real time. As data from the pandemic accumulates, it is clear that COVID-19 is impacting some parts of society more than others. Unfortunately, there is an almost complete overlap between COVID-19 risk factors and conditions that are already represented as health disparities, such as hypertension, diabetes, heart disease, lung disease and immune disorders. In this review, we discuss our current understanding of the physiological and pathophysiological pathways that link these diseases to COVID-19 outcome. An increased awareness of the factors underlying this issue, both societal and medical, is needed to understand the long-term implications and possible solutions needed going forward.

Herbicide Widespread: The Effects of Pethoxamid on Nonalcoholic Fatty Liver Steatosis In Vitro

Pethoxamid is a widespread herbicidal product, presenting itself as an extremely flexible active substance and with a high potential for use as an herbicide for preemergence. The emergence of multiple resistance in crops has been addressed using combinations of preemergence and postemergence herbicides in the same seeding-harvest cycle. A winning combination of pethoxamid and glyphosate mainly affected the acidobacteria population. Glyphosate scientific literature has demonstrated an observational link between herbicide exposure and liver disease in human subjects. Identifying and ranking the risk to the public that pethoxamid could exert on target organs has not been evaluated so far. Due to similarities to glyphosate, we did look at the effect of pethoxamid on impaired liver cells HepG2, using a nonalcoholic fatty liver disease (NAFLD) cell model in vitro. Pethoxamid was cytotoxic starting at 1 ppm. Fatty acid accumulation (FA) was enhanced while low doses of pethoxamid slightly decreased LDH protein expression compared to FA-treated HepG2. The same trend was observed for cytochrome c. Based on our data, we can argue that NAFLD hepatic cells react to pethoxamid trying detoxifying strategies, ready to undergo cell death to avoid further degeneration. Downregulation of cytochrome can lead to the hypothesis that pethoxamid should not induce herbicide resistance.

Active vitamin D impedes the progression of non-alcoholic fatty liver disease by inhibiting cell senescence in a rat model

OBJECTIVE

Non-alcoholic fatty liver disease (NAFLD) refers to an accumulation of excess fat in liver due to causes other than alcohol use. The relationship between vitamin D (VD) and NAFLD has been previously studied. Therefore, we aimed to explore the mechanism involved active VD regulating the progression of NAFLD by inhibiting cell senescence and to provide a potential approach for further nutritional treatment of NAFLD.

METHODS

Following the induction with high-fat diet and intraperitoneal injection of corn oil, the successfully established NAFLD rat models were treated with 1,25(OH)₂D₃ at 1μg/kg, 5μg/kg or 10μg/kg. Meanwhile, the levels of factors related to oxidative stress, cell senescence, the p53-p21 signaling pathway and inflammation in liver were determined. Then, cell senescence was also measured by using senescence-associated β-galactosidase (SAβ-gal) staining.

RESULTS

It was also found that active VD increased the concentration of VD in serum and VDR in liver of NAFLD rats, and alleviated hepatic fibrosis. Besides, treatment of 1,25(OH)₂D₃ at 1μg/kg, 5μg/kg or 10μg/kg reduced oxidative stress and inflammation, inhibited the p53-p21 signaling pathway and consequent cell senescence. Furthermore, treatment of 1,25(OH)₂D₃ at a dosage of 5μg/kg made the most impact on these factors.

CONCLUSION

Collectively, the evidences from this study demonstrated that active VD could alleviate the development of NAFLD through blocking the p53-p21 signaling pathway, which provided a novel nutritional therapeutic insight for NAFLD.

Outcomes of liver transplantation using moderately steatotic liver from donation after cardiac death (DCD)

Background

Liver grafts from donation after cardiac death (DCD) with moderate steatosis (MS) are generally considered unsui for liver transplantation (LT) because DCD and MS are independent risk factors of poor prognosis of LT. Many centers have begun to accept this type of liver graft. However, the clinical outcomes are indeed controversial. This study aimed to examine the outcomes after LT of using such liver grafts.

Methods

This study retrospectively reviewed our experiences in 80 allografts from May 2015 to September 2019. A total of 16 allografts using MS liver grafts from DCD (MS-DCD group) were compared with a matched control group of 64 allografts using a nonsteatotic liver graft (NS group) (1:4 ratio). Postoperative outcomes, including primary nonfunction (PNF), initial poor function (IPF), postoperative complications, and graft/patient survival rates, were extracted for pooled analysis.

Results

Recipient and surgical characteristics of patients and clinical data of donors between MS-DCD group and NS group were balanced. No significant differences were observed in hepatitis B virus (HBV) infection, model for end-stage liver disease (MELD) score, cold ischemia time (CIT), donor risk index, warm ischemia time (WIT). A significant difference was detected in the incidence of initial poor function (IPF) (11/16 vs. 26/64; P=0.02), and the average peak value of aspartate transaminase (AST) (3,469 vs. 1,295; P<0.01) was significantly higher in the steatosis group. Meanwhile, alanine transaminase (ALT) was only higher on day 1, and international normalized ratio (INR) level was only higher on days 1 and 3 and disappeared on day 7. The serum total bilirubin (TB) was the same between the two groups. Postoperative complications were similar between the two groups. The 90-day, 1-year, and 3-year survival rates in patients and grafts between the two groups were similar (patient survival(MS-DCD group vs. NS group): 75% vs. 85.9%, 75% vs. 78.1%, 68.8% vs. 71.9%, log-rank test, P=0.77; graft survival(MS-DCD group vs. NS group): 75% vs. 84.4%, 75% vs. 75%, 68.8% vs. 68.8%, log-rank test, P=0.79).

Conclusions

After rigorous evaluation, it was found that moderately steatotic liver from DCD is an effective means to expand the source of liver supply.

Microsteatosis in Livers From Donation After Circulatory Death Donors Is Associated With Inferior Outcomes Following Liver Transplantation

The acceptable threshold remains unknown for the percentage of macrosteatosis (MaS) and microsteatosis (MiS) to yield optimal outcomes after donation after circulatory death (DCD) liver transplantation (LT). The purpose of this analysis was to determine the impact of donor liver MaS and MiS on DCD LT outcomes. Using the Organ Procurement and Transplantation Network database, we analyzed pretransplant biopsy results from adult, solitary, DCD livers transplanted between January 1, 2006, and December 31, 2017. Kaplan-Meier analysis was used to assess graft and patient survival based on MaS and MiS severity. MiS was divided into the groups MiS ≤10% and >10%. MaS was divided into the groups MaS ≤15% and >15%. Of 7757 recovered DCD livers, 11.4% (n = 885) were biopsied and transplanted. Patients who received DCD livers with MaS >15% had significantly worse patient survival (P < 0.04), and those with MiS >10% demonstrated inferior graft and patient survival (P < 0.02). In multivariate analyses including known risk factors, both MaS >15% and MiS >10% were associated with increased risk of graft failure and patient mortality (P < 0.03). Recipient and donor age >60 years were also associated with increased risk of graft failure and patient death. This analysis demonstrates that MaS >15% and MiS >10% are additional risk factors for graft loss and patient mortality in DCD LT.

Racial disparities in nonalcoholic fatty liver disease clinical trial enrollment: A systematic review and meta-analysis

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) has a heterogeneous distribution across racial and ethnic groups, with a disproportionate burden among Hispanics. Although there are currently no approved therapies for treatment of NAFLD, several therapies have been investigated in clinical trials.

AIM

To analyze the inclusion of racial and ethnic minority groups in clinical trials for NAFLD.

METHODS

We performed a systematic review of North American, English-language, prospective studies for NAFLD therapies published from 2005 to 2019. Racial and ethnic enrollment data were recorded for each eligible study. Meta-analysis was performed to compute pooled prevalence of different racial and ethnic groups, followed by further subgroup analyses. These analyses were based on diagnosis of non-alcoholic steatohepatitis (NASH) and timing of study on enrollment by ethnicity. Descriptive statistics were performed to compare racial and ethnic study enrollment to previously reported NAFLD population prevalence.

RESULTS

Thirty-eight studies met criteria for inclusion in the systematic review. When reported, median age of enrolled subjects was 49 years (range 41.5-58) with 56% female participants. NAFLD was defined through biopsy findings in 79% (n = 30) of the studies. Of the included articles, treatment modalities ranged from medications (n = 28, 74%), lifestyle interventions (n = 5, 13%), bariatric surgery (n = 4, 11%) and phlebotomy (n = 1, 2%). Twenty-eight studies (73%) included racial and/or ethnic demographic information, while only 17 (45%) included information regarding Hispanic participation. Of the 2983 patients enrolled in all eligible trials, a total of only 346 (11.6%) Hispanic participants was reported. Meta-analysis revealed a pooled Hispanic prevalence of 24.3% (95% confidence interval 16.6-32.0, I² 94.6%) among studies documenting Hispanic enrollment. Hispanic enrollment increased over time from 15% from 2005-2014 to 37% from 2015-2019.

CONCLUSION

In a meta-analysis of NAFLD trials, documentation of racial/ethnic demographic data occurred in less than half of studies. Standardization of reporting of race/ethnicity and targeted interventions toward minority recruitment are needed to improve diversity of enrollment.

Identification of CYP46A1 as a new regulator of lipid metabolism through CRISPR-based whole-genome screening

Abnormal lipid droplet (LD) metabolism causes a variety of disorders, especially to nonalcoholic fatty liver disease (NAFLD). But the mechanism of abnormal aggregation of LD is still not fully elucidated. Here, Genome-wide CRISPR-Cas9 knockout (GeCKO) screening was employed to identify candidate genes regulating LD metabolism in L02 cell. We analyzed simultaneously the transcriptomics of liver tissues of NAFLD to find potential genes involved in pathogenesis of NAFLD. After integration these data, we found that the expression of 43 candidate genes from the GeCKO screening was also decreased in tissues of NAFLD patients. Many of these 43 overlapping genes have been reported to play an important role in the formation of LD. Subsequently, we focused on CYP46A1, one of 43 candidate genes and mitochondria-related genes. We confirmed that the protein expression of CYP46A1 is deceased in tissues of NAFLD patients. Downregulation or overexpression of CYP46A1 affected LD accumulation in vitro. Deficiency of CYP46A1 impaired mitochondrial morphology and function, which may be responsible for the accumulation of LD. In summary, this study explored regulatory factors of LD accumulation at the whole-genome level, and demonstrated that CYP46A1 regulated LD formation involving in NAFLD pathogenesis. It provides new clues for studying the molecular mechanisms of diseases related to abnormal lipid metabolism.

Necroptosis in Hepatosteatotic Ischaemia-Reperfusion Injury

While liver transplantation remains the sole treatment option for patients with end-stage liver disease, there are numerous limitations to liver transplantation including the scarcity of donor livers and a rise in livers that are unsuitable to transplant such as those with excess steatosis. Fatty livers are susceptible to ischaemia-reperfusion (IR) injury during transplantation and IR injury results in primary graft non-function, graft failure and mortality. Recent studies have described new cell death pathways which differ from the traditional apoptotic pathway. Necroptosis, a regulated form of cell death, has been associated with hepatic IR injury. Receptor-interacting protein kinase 3 (RIPK3) and mixed-lineage kinase domain-like pseudokinase (MLKL) are thought to be instrumental in the execution of necroptosis. The study of hepatic necroptosis and potential therapeutic approaches to attenuate IR injury will be a key factor in improving our knowledge regarding liver transplantation with fatty donor livers. In this review, we focus on the effect of hepatic steatosis during liver transplantation as well as molecular mechanisms of necroptosis and its involvement during liver IR injury. We also discuss the immune responses triggered during necroptosis and examine the utility of necroptosis inhibitors as potential therapeutic approaches to alleviate IR injury.

Non-alcoholic fatty liver disease: A review with clinical and pathological correlation

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in North America and Europe, with increasing prevalence in other regions of the world. Its spectrum encompass steatosis, non-alcoholic steatohepatitis (NASH), fibrosis and cirrhosis. It is considered as the manifestation of metabolic syndrome in liver, and its development and progression is influenced by complex interaction of environmental and genetic factors. In this review we discuss the histopathological features, differential diagnoses, and the commonly used grading and staging systems of NAFLD. NAFLD associated with other diseases, histological changes after therapeutic intervention and recurrence or occurrence of NAFLD after liver transplantation are also addressed.

N-Acetylcysteine Reduced Ischemia and Reperfusion Damage Associated with Steatohepatitis in Mice

N-acetylcysteine (NAC) is a pharmacological alternative with great potential for reducing the deleterious effects of surgical procedures on patients with steatohepatitis. We evaluated the effect of NAC on hepatic ischemia/reperfusion (I/R) injury in C57BL/6J mice, 8 weeks-old, weighing 25-30 g, with steatohepatitis induced by a methionine- and choline-deficient (MCD) diet. Groups: MCD group (steatohepatitis), MCD-I/R group (steatohepatitis plus 30 min of 70% liver ischemia and 24 h of reperfusion), MCD-I/R+NAC group (same as MCD-I/R group plus 150 mg/kg NAC 15 min before ischemia), and control group (normal AIN-93M diet). Liver enzymes and histopathology; nitrite and TBARS (thiobarbituric acid reactive substances) levels; pro-inflammatory cytokines; antioxidants enzymes; Nrf2 (nuclear factor erythroid-2-related factor 2) expression; and apoptosis were evaluated. In the group treated with NAC, reductions in inflammatory infiltration; AST (aspartate aminotransferase), nitrite, and TBARS levels; GPx (gutathione peroxidase) activity; cytokines synthesis; and number of apoptotic cells were observed while the GR (glutathione reductase) activity was increased. No differences were observed in Nfr2 expression or in SOD (superoxide dismutase), CAT (catalase), and GST (glutathione S-transferase) activities. Thus, it may be concluded that NAC exerts beneficial effects on mice livers with steatohepatitis submitted to I/R by reducing oxidative stress, inflammatory response, and cell death.

Estimated Cardiorespiratory Fitness Attenuates the Impacts of Sarcopenia and Obesity on Non-Alcoholic Fatty Liver in Korean Adults

This population-based, cross-sectional study examined the preventive role of non-exercise-based estimation of cardiorespiratory fitness (eCRF) against the impacts of sarcopenia and obesity on the non-alcoholic fatty liver (NAFL) in Korean adults. Data were obtained from the 2008–2011 Korea National Health and Nutrition Examination Surveys IV and V (n = 14,015 Koreans aged ≥ 18 years, 64% women). eCRF was calculated with the age- and sex-specific algorithms, and classified as lower (lowest 25%), middle (middle 50%) and upper (highest 25%). Individuals were classified as optimal (i.e., the absence of both sarcopenia and obesity), sarcopenia (i.e., the presence of sarcopenia), obesity (i.e., the presence of obesity) or sarcopenic obesity (i.e., the coexistence of sarcopenia and obesity). Limited to the sarcopenia phenotype, the adjusted odds ratio (OR) of NAFL was 2.2 (95% confidence interval, CI, 1.5–3.1) for the lower eCRF, 1.6 (95% CI, 1.3–2.1) for the middle eCRF and 2.1 (95% CI, 1.4–3.1) for the upper eCRF, compared to the optimal phenotype. Limited to the obesity phenotype, the adjusted OR of NAFL was 2.9 (95% CI, 2.0–4.2) for the lower eCRF, 3.5 (95% CI, 2.7–4.6) for the middle eCRF and 1.8 (95% CI, 1.2–2.8) for the upper eCRF, compared to the optimal phenotype. Limited to the sarcopenic obesity phenotype, the adjusted OR of NAFL was 5.9 (95% CI, 4.3–8.2) for the lower eCRF, 4.2 (95% CI, 3.2–5.5) for the middle eCRF and 2.5 (95% CI, 1.5–4.1) for the upper eCRF, compared to the optimal phenotype. The current findings suggest that high eCRF attenuates the individual and synergistic impacts of sarcopenia and obesity on NAFL in Korean adults.

Synbiotics Alter Fecal Microbiomes, But Not Liver Fat or Fibrosis, in a Randomized Trial of Patients With Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

Dysbiosis of the intestinal microbiota has been associated with nonalcoholic fatty liver disease (NAFLD). We investigated whether administration of a synbiotic combination of probiotic and prebiotic agents affected liver fat content, biomarkers of liver fibrosis, and the composition of the fecal microbiome in patients with NAFLD.

METHODS

We performed a double-blind phase 2 trial of 104 patients with NAFLD in the United Kingdom. Participants (mean age, 50.8 ± 12.6 years; 65% men; 37% with diabetes) were randomly assigned to groups given the synbiotic agents (fructo-oligosaccharides, 4 g twice per day, plus Bifidobacterium animalis subspecies lactis BB-12; n = 55) or placebo (n = 49) for 10-14 months. Liver fat content was measured at the start and end of the study by magnetic resonance spectroscopy, and liver fibrosis was determined from a validated biomarker scoring system and vibration-controlled transient elastography. Fecal samples were collected at the start and end of the study, the fecal microbiome were analyzed by 16S ribosomal DNA sequencing.

RESULTS

Mean baseline and end-of-study magnetic resonance spectroscopy liver fat percentage values were 32.3% ± 24.8% and 28.5% ± 20.1% in the synbiotic group and 31.3% ± 22% and 25.2% ± 17.2% in the placebo group. In the unadjusted intention-to-treat analysis, we found no significant difference in liver fat reduction between groups (β = 2.8; 95% confidence interval, -2.2 to 7.8; P = .30). In a fully adjusted regression model (adjusted for baseline measurement of the outcome plus age, sex, weight difference, and baseline weight), only weight loss was associated with a significant decrease in liver fat (β = 2; 95% confidence interval, 1.5-2.6; P = .03). Fecal samples from patients who received the synbiotic had higher proportions of Bifidobacterium and Faecalibacterium species, and reductions in Oscillibacter and Alistipes species, compared with baseline; these changes were not observed in the placebo group. Changes in the composition of fecal microbiota were not associated with liver fat or markers of fibrosis.

CONCLUSIONS

In a randomized trial of patients with NAFLD, 1 year of administration of a synbiotic combination (probiotic and prebiotic) altered the fecal microbiome but did not reduce liver fat content or markers of liver fibrosis. (ClinicalTrials.gov, Number: NCT01680640).

Epidemiology of non-alcoholic and alcoholic fatty liver diseases

Liver diseases are fast emerging as global health priorities. Fatty liver is described in the setting of non-alcoholic fatty liver disease (NAFLD) as well as alcoholic liver disease (ALD), the pathogenesis of excess fat being different in the two conditions while both are important components of the changing face of burden of liver diseases worldwide. They are intimately associated with a globalized economy and an increasingly homogenous socio- cultural order with a westernized lifestyle. The accompanying adoption of a progressively sedentary life, consumption of diet dense in calories facilitate development of NAFLD while a spiraling upward trend in alcohol use along with earlier age of drinking as well as increased amount of per capita alcohol consumption increases the prevalence of ALD globally. Adverse health outcomes in NAFLD as well as ALD are caused not only by progressive liver fibrosis that is the most significant factor for liver related and all-cause mortality in both but also by non-liver (cardiovascular, cancer, accidents, neurological) clinical outcomes that calls for a multidisciplinary and social approach to these conditions. We present here an outline of facets of epidemiology of both NAFLD as well as ALD along with its' public health implications. A broad-based integrated approach that incorporates social, behavioral as well as biological targets need to be undertaken at a health system level in a planned manner for these evolving liver health priorities that disproportionately challenges the low- and middle-income countries of Asia, South America and Africa.

Burden of Disease due to Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is rapidly becoming the most common liver disease in both Western populations and other parts of the world. This review discusses the prevalence and incidence of NAFLD in various regions around the world. The methodology used to identify the epidemiology and classify the stages of the disease is described. The impact of the disease on individuals, looking at both liver-related and extrahepatic consequences of the disease, is then discussed. Finally, the economic and societal impact of the disease is discussed.

The Effects of RKI-1447 in a Mouse Model of Nonalcoholic Fatty Liver Disease Induced by a High-Fat Diet and in HepG2 Human Hepatocellular Carcinoma Cells Treated with Oleic Acid

Background

This study aimed to investigate the effects of RKI-1447, a selective inhibitor of Rho-associated ROCK kinases, in a mouse model of nonalcoholic fatty liver disease (NAFLD) induced by a high-fat diet, and in oleic acid-treated HepG2 human hepatocellular carcinoma cells in vitro.

Material/Methods

Four study groups of mice included: the control group; the high-fat diet (HFD) group; the HFD+RKI-1447 (2 mg/kg) group; and the HFD+RKI-1447 (8 mg/kg) group. Mice were fed a high-fat diet for 12 weeks. Mice in the HFD+RKI-1447 groups were fed a high-fat diet for 12 weeks and treated with RKI-1447 twice weekly for three weeks. The HepG2 human hepatocellular carcinoma cells were treated with or without RKI-1447 for 2 h and treated with oleic acid for 24 h.

Results

In the mouse model of NAFLD, RKI-1447 reduced insulin resistance and the levels of alanine aminotransferase (ALT), aspartate transaminase (AST), total cholesterol, triglyceride, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), malondialdehyde (MDA), and superoxide dismutase (SOD). RKI-1447 reduced the histological changes in the mouse model of NAFLD in mice fed a high-fat diet and significantly inhibited the generations of triglyceride, IL-6, and TNF-α. RKI-1447 reduced the levels of oxidative stress in HepG2 cells treated with oleic acid and significantly down-regulated the expression of RhoA, ROCK1, ROCK2, toll-like receptor 4 (TLR4), p-TBK1, and p-IRF3. RKI-1447 treatment also inhibited RhoA expression.

Conclusions

In a mouse model of NAFLD, RKI-1447 inhibited ROCK and modulated insulin resistance, oxidative stress, and inflammation through the ROCK/TLR4/TBK1/IRF3 pathway.

New Perspectives on Genetic Prediction for Pediatric Metabolic Associated Fatty Liver Disease

Non-alcoholic or recently re-defined metabolic associated fatty liver disease (MAFLD), a spectrum of progressive hepatic disease, has become a public health issue in obese children and adolescents. MAFLD is a complex metabolic disease strongly associated with obesity and insulin resistance. It is not known why not every obese subject will develop MAFLD. Different ethnic/racial groups display differences in MAFLD prevalence, indicating genetic factor plays a role. In the past two decades, sequence variations in genetic loci, including PNPLA3, TM6SF2, GCKR, MBOAT7, HSD17B13, etc. have been shown to confer susceptibility to MAFLD in children and adults. This review article provides an updated viewpoint of genetic predictors related to pediatric MAFLD. We discuss whether these susceptible genes can be clinically used for risk stratification and personalized care. Understanding human genetics and molecular mechanisms can give important information not only for prediction of risk but also on how to design drugs. In view of current epidemic of MAFLD worldwide, it is necessary to identify which children with MAFLD progress rapidly and need earlier intervention. In the future, a comprehensive analysis of individualized genetic and environmental factors may help assess the risk of children with MAFLD and personalize their treatment.

Pin1 Plays Essential Roles in NASH Development by Modulating Multiple Target Proteins

Pin1 is one of the three known prolyl-isomerase types and its hepatic expression level is markedly enhanced in the obese state. Pin1 plays critical roles in favoring the exacerbation of both lipid accumulation and fibrotic change accompanying inflammation. Indeed, Pin1-deficient mice are highly resistant to non-alcoholic steatohepatitis (NASH) development by either a high-fat diet or methionine-choline-deficient diet feeding. The processes of NASH development can basically be separated into lipid accumulation and subsequent fibrotic change with inflammation. In this review, we outline the molecular mechanisms by which increased Pin1 promotes both of these phases of NASH. The target proteins of Pin1 involved in lipid accumulation include insulin receptor substrate 1 (IRS-1), AMP-activated protein kinase (AMPK) and acetyl CoA carboxylase 1 (ACC1), while the p60 of the NF-kB complex and transforming growth factor β (TGF-β) pathway appear to be involved in the fibrotic process accelerated by Pin1. Interestingly, Pin1 deficiency does not cause abnormalities in liver size, appearance or function. Therefore, we consider the inhibition of increased Pin1 to be a promising approach to treating NASH and preventing hepatic fibrosis.

Diet-Induced Rat Model of Gradual Development of Non-Alcoholic Fatty Liver Disease (NAFLD) with Lipopolysaccharides (LPS) Secretion

Background: Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver disorders in industrialized Western countries. The prevalence of the disease is estimated to range from 4% to 46% worldwide. The aim of study was to develop an animal model with gradual NAFLD development. Methods: Sprague-Dawley rats were fed a high-fat and high-cholesterol (HFHCh) diet. The rats from the study and control groups were sacrificed after 2, 4, 8, 12, 16, and 20 weeks of dietary exposure. Results: Analysis of biochemical parameters showed that after only two weeks, ALT and cholesterol concentration in serum were elevated. After 4 weeks, TNF-α and HOMA-IR were significantly higher compared to the control group. NAFLD progression started after 12 weeks of diet-weight gain and increased LPS secretions were noticed. During the experiment, rats induced steatosis (from stage 0/1 after 4 weeks to stage 2/3 after 20 weeks), inflammation (from stage 0/1 after 4 weeks to stage 1/2 after 20 weeks), and fibrosis (from stage 1 after 12 weeks to stage 2 after 20 weeks). Conclusion: We can assume that the presented model based on the HFHCh diet induced gradual development of NAFLD. We confirmed that the animal NAFLD model increases LPS secretions during disease progression.

Disparities in Hepatocellular Carcinoma Incidence in California: An Update

BACKGROUND

Given changes in hepatocellular carcinoma (HCC) incidence and the ethnodemographic landscape, we analyzed recent HCC incidence patterns and trends in California.

METHODS

Using 47,992 primary, invasive HCC cases diagnosed from 1988 to 2014 from the California Cancer Registry, we calculated age-adjusted incidence rates (IR), annual percent change (APC), and 95% confidence intervals (CI) by sex, race/ethnicity, and nativity among Hispanics and Asian ethnic groups.

RESULTS

Compared with non-Hispanic Whites (NHW), all other racial/ethnic groups had higher HCC incidence. Vietnamese had the highest IRs (males: 47.4, 95% CI, 45.3-49.5; females: 14.1, 95% CI, 13.0-15.3). Foreign-born Chinese, Japanese, Korean, and Vietnamese had higher incidence than U.S.-born. The reverse was observed for Hispanic males, whereas no differences by nativity were seen for Hispanic females. IRs increased most for NHWs. Among Asians, male and female Filipinos and Japanese males experienced rate increases, whereas male and female Koreans and Chinese males experienced rate decreases. U.S.-born male and female Hispanics and Japanese had higher APCs than foreign-born, as did Filipino males, whereas Chinese males had a reverse pattern. Annual increases in HCC incidence slowed down in recent years for U.S.-born Hispanic males and females and stabilized among male NHWs and non-Hispanic Blacks. For some Asian groups, early time periods exhibited increasing/stable APCs, whereas later time periods showed decreasing APCs.

CONCLUSIONS

We found significant racial/ethnic and nativity differences in HCC IRs and trends.

IMPACT

With changing trends, closer surveillance of HCC incidence by disaggregated race/ethnicity and nativity is warranted among Hispanics and Asians.

Degradation of splicing factor SRSF3 contributes to progressive liver disease

Serine rich splicing factor 3 (SRSF3) plays a critical role in liver function and its loss promotes chronic liver damage and regeneration. As a consequence, genetic deletion of SRSF3 in hepatocytes caused progressive liver disease and ultimately led to hepatocellular carcinoma. Here we show that SRSF3 is decreased in human liver samples with non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), or cirrhosis that was associated with alterations in RNA splicing of known SRSF3 target genes. Hepatic SRSF3 expression was similarly decreased and RNA splicing dysregulated in mouse models of NAFLD and NASH. We showed that palmitic acid-induced oxidative stress caused conjugation of the ubiquitin like NEDD8 protein to SRSF3 and proteasome mediated degradation. SRSF3 was selectively neddylated at lysine11 and mutation of this residue (SRSF3-K11R) was sufficient to prevent both SRSF3 degradation and alterations in RNA splicing. Finally prevention of SRSF3 degradation in vivo partially protected mice from hepatic steatosis, fibrosis and inflammation. These results highlight a neddylation-dependent mechanism regulating gene expression in the liver that is disrupted in early metabolic liver disease and may contribute to the progression to NASH, cirrhosis and ultimately hepatocellular carcinoma.

Association between Lysosomal Dysfunction and Obesity-Related Pathology: A Key Knowledge to Prevent Metabolic Syndrome

Obesity causes various health problems, such as type 2 diabetes, non-alcoholic fatty liver disease, and cardio- and cerebrovascular diseases. Metabolic organs, particularly white adipose tissue (WAT) and liver, are deeply involved in obesity. WAT contains many adipocytes with energy storage capacity and secretes adipokines depending on the obesity state, while liver plays pivotal roles in glucose and lipid metabolism. This review outlines and underscores the relationship between obesity and lysosomal functions, including lysosome biogenesis, maturation and activity of lysosomal proteases in WAT and liver. It has been revealed that obesity-induced abnormalities of lysosomal proteases contribute to inflammation and cellular senescence in adipocytes. Previous reports have demonstrated obesity-induced ectopic lipid accumulation in liver is associated with abnormality of lysosomal proteases as well as other lysosomal enzymes. These studies demonstrate that lysosomal dysfunction in WAT and liver underlies part of the obesity-related pathology, raising the possibility that strategies to modulate lysosomal function may be effective in preventing or treating the metabolic syndrome.

Ability of prebiotic polysaccharides to activate a HIF1α-antimicrobial peptide axis determines liver injury risk in zebrafish

Natural polysaccharides have received much attention for their ability to ameliorate hepatic steatosis induced by high-fat diet. However, the potential risks of their use have been less investigated. Here, we show that the exopolysaccharides (EPS) from Lactobacillus rhamnosus GG (LGG) and L. casei BL23 reduce hepatic steatosis in zebrafish fed a high-fat diet, while BL23 EPS, but not LGG EPS, induce liver inflammation and injury. This is due to the fact that BL23 EPS induces gut microbial dysbiosis, while LGG EPS promotes microbial homeostasis. We find that LGG EPS, but not BL23 EPS, can directly activate intestinal HIF1α, and increased HIF1α boosts local antimicrobial peptide expression to facilitate microbial homeostasis, explaining the distinct compositions of LGG EPS- and BL23 EPS-associated microbiota. Finally, we find that liver injury risk is not confined to Lactobacillus-derived EPS but extends to other types of commonly used natural polysaccharides, depending on their HIF1α activation efficiency.

Ursodeoxycholic acid is a GPBAR1 agonist and resets liver/intestinal FXR signaling in a model of diet-induced dysbiosis and NASH

Obeticholic acid (OCA) is a farnesoid-X-receptor (FXR) ligand, shown effective in reducing steatosis and fibrosis in NASH patients. However, OCA causes major side effects including pruritus, while increases the risk for liver decompensation in cirrhotic patients. Ursodeoxycholic acid (UDCA), is a safe and unexpensive bile acid used in the treatment of liver disorders whose mechanism of action is poorly defined. Here we have compared the effects of OCA and UDCA in a mouse model of NASH. In mice exposed to a diet rich in fat/cholesterol and fructose (HFD-F), treatment with OCA or UDCA effectively prevented body weight gain, insulin resistance, as demonstrated by OGTT, and AST plasma levels. After 12 weeks HFD-F mice developed liver microvesicular steatosis, inflammation and mild fibrosis, increased expression of inflammatory (TNFα, IL6, F4/80) and fibrosis (αSma, Col1α1, Tgfβ) markers, reduced liver expression of FXR, dysregulated liver FXR signaling and elevated levels of Tauro-α and β-muricholic acid (T-α and βMCA), two FXR antagonists in mice. Both compounds prevented these changes and improved liver histopathology. OCA reduced primary bile acid synthesis worsening the T-CA/T-βMCA ratio. UDCA effectively transactivated GPBAR1 in vitro. By RNAseq analysis we found that among over 2400 genes modulated by the HFD-F, only 32 and 60 genes were modulated by OCA and UDCA, with only 3 genes (Dbp, Adh7, Osgin1) being modulated by both agents. Both agents partially prevented the intestinal dysbiosis. CONCLUSIONS: UDCA is a GPBAR1 ligand and exerts beneficial effects in a rodent model of NASH by activating non-overlapping pathway with OCA.

The anti-inflammatory potential of diet and nonalcoholic fatty liver disease: the ATTICA study

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is correlated with low-grade inflammation and dietary habits. Until today, there have been limited epidemiologic data assessing the role of diet's inflammatory potential on NAFLD. The aim was to evaluate the relationship between an anti-inflammatory diet, as reflected by the Dietary Anti-Inflammation Index (D-AII), and NAFLD among cardiovascular disease (CVD)-free adults.

METHODS

ATTICA is a prospective, population-based study that recruited 3042 adults without pre-existing CVD from the Greek population (Whites; age ⩾18 years; 1514 men and 1528 women). D-AII was calculated using a standard procedure. The baseline study captured various sociodemographic, lifestyle and clinical characteristics as well as hepatic markers. These were used to calculate four NAFLD assessment indices: triglyceride-glucose (TyG) index, fatty liver index (FLI), hepatic steatosis index (HSI), and NAFLD Fatty Liver Score (NAFLD-FLS). Specific cutoffs were applied to capture NAFLD.

RESULTS

D-AII showed a significant inverse association with NAFLD, applying the four indices with NAFLD cutoffs [odds ratio (OR) with 95% confidence interval (CI); TyG (0.95, 0.93-0.98); HSI (0.89, 0.86-0.92); FLI (0.88, 0.85-0.91); NAFLD-FLS (0.89, 0.86-0.92)], after adjusting for various confounders. Participants in the highest D-AII tertile had lower odds of having NAFLD, compared with those in the lowest D-AII tertile [(OR, 95% CI); TyG (0.33, 0.24-0.47); HSI (0.13, 0.08-0.23); FLI (0.05, 0.02-0.11); NAFLD-FLS (0.13, 0.07-0.23)]. Anti-inflammatory nutrition was related to lower odds of NAFLD among daily alcohol drinkers and individuals with metabolic syndrome.

CONCLUSIONS

Anti-inflammatory diet is an important predictor of NAFLD among adults without pre-existing CVD. Adherence to a high anti-inflammatory diet seems to contribute to NAFLD prevention.

Transcriptome Analysis of Dual FXR and GPBAR1 Agonism in Rodent Model of NASH Reveals Modulation of Lipid Droplets Formation

Non-alcoholic steatohepatitis (NASH) is a progressive, chronic, liver disease whose prevalence is growing worldwide. Despite several agents being under development for treating NASH, there are no drugs currently approved. The Farnesoid-x-receptor (FXR) and the G-protein coupled bile acid receptor 1 (GPBAR1), two bile acid activated receptors, have been investigated for their potential in treating NASH. Here we report that BAR502, a steroidal dual ligand for FXR/GPBAR1, attenuates development of clinical and liver histopathology features of NASH in mice fed a high fat diet (HFD) and fructose (F). By RNAseq analysis of liver transcriptome we found that BAR502 restores FXR signaling in the liver of mice feed HFD-F, and negatively regulates a cluster of genes including Srebf1 (Srepb1c) and its target genes-fatty acid synthase (Fasn) and Cell death-inducing DFF45-like effector (CIDE) genes, Cidea and Cidec-involved in lipid droplets formation and triglycerides storage in hepatocytes. Additionally, BAR502 increased the intestinal expression of Fgf15 and Glp1 and energy expenditure by white adipose tissues. Finally, exposure to BAR502 reshaped the intestinal microbiota by increasing the amount of Bacteroidaceae. In conclusion, we have shown that dual FXR/GPBAR1 agonism might have utility in treatment of NASH.

Circadian Clock Genes in the Metabolism of Non-alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a common disease, which is characterized by the accumulation of triglycerides in the hepatocytes without excess alcohol intake. Circadian rhythms can participate in lipid, glucose, and cholesterol metabolism and are closely related to metabolism seen in this disease. Circadian clock genes can modulate liver lipid metabolism. Desynchrony of circadian rhythms and the influences imparted by external environmental stimuli can increase morbidity. By contrast, synchronizing circadian rhythms can help to alleviate the metabolic disturbance seen in NAFLD. In this review, we have discussed the current research connections that exist between the circadian clock and the metabolism of NAFLD, and we have specifically focused on the key circadian clock genes, Bmal1, Clock, Rev-Erbs, Rors, Pers, Crys, Nocturnin, and DECs.

Incidence of Recurrent NASH-Related Allograft Cirrhosis

BACKGROUND

Cirrhosis secondary to nonalcoholic steatohepatitis (NASH) is projected to become the leading indication for liver transplantation (LT) in the USA in the next decade. The long-term implications of post-LT NASH, specifically on the development of allograft cirrhosis, are not well known.

METHODS

A retrospective cohort of patients at a single large center undergoing LT for NASH from 2000 to 2015 was identified using a prospectively collected database. A total of 226 patients undergoing LT for NASH were identified. Mean follow-up for the cohort was 7 years. Seventy-five percent of patients underwent at least one liver biopsy post-LT.

RESULTS

Eighty-one patients (36%) developed recurrence of biopsy-proven NASH. Fifteen patients developed bridging fibrosis but only four patients (1.8%) progressed to recurrent NASH cirrhosis at a mean of 9 years post-LT. Body mass index at the time of LT was statistically higher in the NASH allograft cirrhosis group. Recurrent disease was less common and less severe in those transplanted with black donors. All four patients with recurrent NASH cirrhosis developed evidence of portal hypertension, but all remained alive at follow-up.

CONCLUSION

Although recurrent NASH following LT is common, the development of allograft cirrhosis is rare. These findings are useful when counseling patients and important to consider during their post-LT care.

Synthesis of new derivatives of boehmeriasin A and their biological evaluation in liver cancer

Two series of boehmeriasin A analogs have been synthesized in short and high yielding processes providing derivatives differing either in the alkaloid's pentacyclic scaffold or its peripheral substitution pattern. These series have enabled, for the first time, comparative studies into key biological properties revealing a new lead compound with exceptionally high activity against liver cancer cell lines in the picomolar range for both well (Huh7, Hep3B and HepG2) and poorly (Mahlavu, FOCUS and SNU475) differentiated cells. The cell death was characterized as apoptosis by cytochrome-C release, PARP protein cleavage and SubG1 cell cycle arrest. Subsequent testing associated apoptosis via oxidative stress with in situ formation of reactive oxygen species (ROS) and altered phospho-protein levels. Compound 19 decreased Akt protein phosphorylation which is crucially involved in liver cancer tumorigenesis. Given its simple synthetic accessibility and intriguing biological properties this new lead compound could address unmet challenges within liver cancer therapy.

A Pathophysiological Model of Non-Alcoholic Fatty Liver Disease Using Precision-Cut Liver Slices

Non-alcoholic fatty liver disease (NAFLD) is a common liver disorder closely related to metabolic syndrome. NAFLD can progress to an inflammatory state called non-alcoholic steatohepatitis (NASH), which may result in the development of fibrosis and hepatocellular carcinoma. To develop therapeutic strategies against NAFLD, a better understanding of the molecular mechanism is needed. Current in vitro NAFLD models fail to capture the essential interactions between liver cell types and often do not reflect the pathophysiological status of patients. To overcome limitations of commonly used in vitro and in vivo models, precision-cut liver slices (PCLSs) were used in this study. PCLSs, prepared from liver tissue obtained from male Wistar rats, were cultured in supraphysiological concentrations of glucose, fructose, insulin, and palmitic acid to mimic metabolic syndrome. Accumulation of lipid droplets was visible and measurable after 24 h in PCLSs incubated with glucose, fructose, and insulin, both in the presence and absence of palmitic acid. Upregulation of acetyl-CoA carboxylase 1 and 2, and of sterol responsive element binding protein 1c, suggests increased de novo lipogenesis in PCLSs cultured under these conditions. Additionally, carnitine palmitoyltransferase 1 expression was reduced, which indicates impaired fatty acid transport and disrupted mitochondrial β-oxidation. Thus, steatosis was successfully induced in PCLSs with modified culture medium. This novel ex vivo NAFLD model could be used to investigate the multicellular and molecular mechanisms that drive NAFLD development and progression, and to study potential anti-steatotic drugs.

High prevalence of non-alcoholic fatty liver disease and metabolic risk factors in Guatemala: A population-based study

BACKGROUND

There are no data on the prevalence of non-alcoholic fatty liver disease (NAFLD) in general population samples in Guatemala or in other Central American countries. The prevalence and distribution of NAFLD and its associated risk factors were evaluated in a population-based sample of adults in Guatemala.

METHODS

Cross-sectional study of 411 men and women 40 years of age or older residing in urban and rural areas of Guatemala. Metabolic outcomes included obesity, central obesity, hypercholesterolemia, diabetes, and metabolic syndrome (MetS). Liver disease outcomes included elevated liver enzymes, elevated Fatty Liver Index (FLI), and elevated FIB-4 score.

RESULTS

The overall prevalence of obesity, central obesity, diabetes, and MetS were 30.9, 74.3, 21.6, and 64.2%, respectively. The fully-adjusted prevalence ratios (95% CI) for obesity, central obesity, diabetes, and MetS comparing women to men were 2.83 (1.86-4.30), 1.72 (1.46-2.02), 1.18 (1.03-1.34), and 1.87 (1.53-2.29), respectively. The overall prevalence of elevated liver enzymes (ALT or AST), elevated FLI, and elevated FIB-4 scores were 38.4, 60.1, and 4.1%, respectively. The fully-adjusted prevalence ratios (95% CI) for elevated liver enzymes (either ALT or AST) and elevated FLI score comparing women to men were 2.99 (1.84-4.86) and 1.47 (1.18-1.84), respectively.

CONCLUSIONS

The prevalence of metabolic abnormalities and liver outcomes in this general population study was very high. The prevalence of metabolic and liver abnormalities was particularly high among women, an observation that could explain the atypical 1:1 male to female ratio of liver cancer in Guatemala.

Compound C Protects Mice from HFD-Induced Obesity and Nonalcoholic Fatty Liver Disease

OBJECTIVES

The aim of this study was to investigate the effects of compound C on an in vivo mouse model of high-fat diet- (HFD-) induced obesity and hepatosteatosis.

METHODS

C57BL/6 mice were fed with a standard diet (n = 5) for 16 weeks and then injected saline once a day for 4 weeks as the normal chow group. Mice (n = 10) were fed with HFD for 16 weeks to induce obesity and hepatosteatosis and then divided into two groups: HFD + vehicle group injected with the vehicle solution (saline) and HFD + compound C group injected with compound C in saline (5 mg/kg i.p., once a day) for 4 weeks. Liver histology was observed. The expression levels of genes related to lipid metabolism and proinflammation in liver tissue were examined. NLRP3 inflammasome expression in liver tissue was detected by the western blot assay. HepG2 cells were pretreated with compound C and/or AICAR for 1 h and then treated with palmitic acid (PA) for 3 h. The cells were collected, and mRNA levels were determined.

RESULTS

There was a significant reduction in body-weight gain and daily food intake in the HFD + compound C group compared with the HFD + vehicle group (p < 0.05). The glucose tolerance test (GTT) and insulin tolerance test (ITT) showed that compound C alleviated insulin resistance. Histology analysis showed a significant reduction of hepatic steatosis by compound C. Compound C also significantly decreased fatty acid synthesis genes, while increased fatty acid oxidation genes. Furthermore, compound C significantly reduced the expression of proinflammatory markers and NLRP3 inflammasome (p < 0.05). Compound C enhanced mRNA levels of SOD1, SOD2, catalase, GPx1, and GPx4 and reduced the p-AMPK/AMPK ratio, which were stimulated by palmitic acid (PA). The effect was enhanced by AICAR.

CONCLUSION

Our data suggest that compound C is a potent NAFLD suppressor and an attractive therapeutic target for hepatic steatosis and related metabolic disorders.

A nationwide survey on non-B, non-C hepatocellular carcinoma in Japan: 2011-2015 update

BACKGROUND

We previously reported that the incidence of hepatocellular carcinoma (HCC) with non-viral etiologies increased rapidly between 1991 and 2010 in Japan.

METHODS

To update this investigation, we enrolled patients who were initially diagnosed as having non-B, non-C HCC at participating hospitals between 2011 and 2015. In addition to the patient characteristics investigated in the previous report, we also investigated the duration of alcohol consumption. The overall survival rate was analyzed using the Kaplan-Meier method, and the hazard function against the body mass index (BMI) was plotted using cubic splines.

RESULTS

A total of 2087 patients were enrolled. The proportion of patients with non-viral etiologies has continued to increase from 10.0% in 1991 to 32.5% in 2015. Patients were also older (median ages, 70-73 years) and more obese (median BMIs, 23.9-24.2 kg/m²), and the proportions of patients with diabetes mellitus (46.1% to 51.6%), hypertension (42.7% to 58.6%), dyslipidemia (14.6% to 22.9%), and fatty liver (24.0% to 28.8%) had all increased significantly. There was a significant inverse relationship between the duration and the amount of daily alcohol consumption. The improvement in the overall survival was relatively small, with a decreased proportion of patients under surveillance (41.3% to 31.6%). A hazard function plot showed a curve similar to that in our previous report, with a lowest hazard of ~ 26 kg/m².

CONCLUSIONS

The proportion of HCC patients with non-viral etiologies continues to increase in Japan. Lifetime total amount of alcohol consumption may be a risk factor.

Caspase Recruitment Domain Protein 6 Protects Against Hepatic Steatosis and Insulin Resistance by Suppressing Apoptosis Signal-Regulating Kinase 1

The rapidly increasing prevalence of metabolic disorders associated with nonalcoholic fatty liver disease (NAFLD) warrants further study of the underlying mechanisms to identify key regulators as targets for the development of therapeutic interventions. Caspase recruitment domain protein 6 (Card6), as a member of the CARD family that regulates cell death and immunity, may potentially control this process. Indeed, Card6 down-regulation was found to be closely associated with the fatty livers observed in NAFLD patients, obese mice, and a palmitate-treated hepatocyte model. Gain-of-function and loss-of-function Card6 mouse models demonstrated that Card6 protected mice from insulin resistance, hepatic steatosis, and inflammatory responses upon high-fat diet administration. Mechanistically, Card6 interacted with and inhibited apoptosis signal-regulating kinase 1 (Ask1) and its subsequent downstream c-Jun N-terminal kinase/p38 signaling. Furthermore, Ask1 was sufficient to mediate Card6 function, and the interaction between Ask1 and Card6 was absolutely required for Card6 function in vivo. Adenovirus-mediated Card6 overexpression in the liver effectively ameliorated insulin resistance and hepatic steatosis in ob/ob mice. Therefore, we identified Card6 as an important negative regulator in NAFLD. Conclusion: Targeting Ask1 by Card6 may be a good strategy to develop a therapeutic method against NAFLD.

Impact of Smoking Cessation in Donor Candidates for Living Donor Liver Transplantation

BACKGROUND

The relationship between smoking cessation and weight gain is well recognized. Examining the link between smoking cessation and weight gain in donor candidates for living donor liver transplantation (LDLT) is an important topic because of the influence of weight gain on the liver. This study assessed body weight (BW) changes after smoking cessation in donor candidates for LDLT.

METHODS

The 27 donor candidates were retrospectively analyzed. The smoking status was determined based on questionnaires administered at the initial presentation, and the candidates were divided into 2 groups: recent quitters and nonsmokers. The changes in BW were compared between the groups.

RESULTS

The recent quitters group included 10 (37.0%) candidates, and the nonsmokers group included 17 (63.0%). In the nonsmokers group, 1 candidate had gained weight since the initial presentation. In contrast, in the recent quitters group, 70.0% of candidates had gained weight since the initial presentation (P < .01). The change in BW from the initial presentation was greater in recent quitters than in nonsmokers (+1.6 kg [+2.4%] vs -0.5 kg [-0.9%]; P < .01). Two candidates in the recent quitters group gained ≥ 5 kg [8%] of weight. One of these 2 candidates was judged to be in a donor-inadequate status because of the appearance of fatty liver.

CONCLUSIONS

Weight gain due to smoking cessation was observed in donor candidates for LDLT. The amount of weight gain after smoking cessation is highly individualized, so everyone concerned with LDLT must be alert to its potential development.

Pharmacological interventions for non-alcoholic fatty liver disease: a systematic review and network meta-analysis

AIM

Several drugs have been used for treating non-alcoholic fatty liver disease (NAFLD). The present study is a network meta-analysis of such drugs.

DESIGN, SETTING AND PATIENTS

Randomised clinical trials comparing drug interventions in patients with NAFLD were analysed. OR and weighted mean difference (95 % CI) were the effect estimates for categorical and numerical outcomes, respectively. Random-effects model was used to generate pooled estimates. Surface under the cumulative ranking curve was used to rank the treatments.

MAIN OUTCOME MEASURES

Proportion of responders was the primary outcome measure and non-alcoholic steatohepatitis scores, liver enzymes, lipid profile, body mass index, homeostatic model assessment of insulin resistance, intrahepatic fat and adverse events were the key secondary outcomes.

RESULTS

116 studies were included in the systematic review and 106 in the meta-analysis. Elafibranor, gemfibrozil, metadoxine, obeticholic acid, pentoxifylline, pioglitazone, probiotics, telmisartan, vildagliptin and vitamin E significantly increased the response rate than standard of care. Various other drugs were observed to modify the secondary outcomes favourably. Probiotics was found with a better response in children; and elafibranor, obeticholic acid, pentoxifylline and pioglitazone in patients with type 2 diabetes mellitus. The quality of evidence observed was either low or very low.

CONCLUSION

In patients with NAFLD, several drugs have been shown to have variable therapeutic benefit. However, the estimates and the inferences should be considered with extreme caution as it might change with the advent of future head-to-head clinical trials.

Non-alcoholic fatty liver disease-associated hepatocellular carcinoma: effect of hepatic steatosis on major hepatocellular carcinoma features at MRI

OBJECTIVE:

To evaluate the effect of hepatic steatosis on LI-RADS® major features at MRI in patients with non-alcoholic fatty liver disease (NAFLD)-associated hepatocellular carcinoma (HCC).

METHODS:

HCC and liver parenchyma features at MRI from 48 consecutive patients with NAFLD and histology proven HCC (mean ± SD; 4.5 ± 3.4 cm) were independently reviewed by three radiologists. Inter-rater agreement was determined by prevalence/bias-adjusted kappa. Hepatic fat signal fraction (FS%) was independently calculated. HCC features were compared by FS% at MRI using logistic regression analysis and histologic steatosis grade using Cochran-Armitage test for trend, stratified by cirrhotic liver morphology or histologic fibrosis stage. Receiver operating characteristic curves were generated to determine the sensitivity and specificity for major HCC features by FS%.

RESULTS:

Major HCC features included arterial phase hyperenhancement (APHE) in 45 (93%), portal venous phase washout (PVWO) in 30 (63%), delayed phase washout (DPWO) in 38 (79%) and enhancing "capsule" in 34 (71%). Cirrhotic morphology was present in 22 (46%). Inter-rater agreement was 0.75 for APHE, 0.42-0.58 for PVWO, 0.58-0.71 for DPWO and 0.38-0.67 for enhancing "capsule". There was an 18%, 14% and 22% increase in the odds of absent PVWO, DPWO and capsule appearance for every 1% increase in hepatic FS% in patients with non-cirrhotic liver morphology (p = 0.011, 0.040 and 0.029, respectively). Hepatic FS% ≥ 14.8% had a sensitivity and specificity of 64 and 100% for absent PVWO and 71 and 90% for absent DPWO in patients with non-cirrhotic liver morphology.

CONCLUSION:

Absent washout and capsule appearance are associated with increasing hepatic steatosis in patients with non-cirrhotic, NAFLD-associated HCC.

ADVANCES IN KNOWLEDGE:

In patients with non-cirrhotic, non-alcoholic fatty liver disease (NAFLD)-associated hepatocellular carcinoma (HCC), absent HCC washout and capsule appearance are associated with increasing hepatic steatosis, thereby potentially impacting the noninvasive imaging diagnosis of HCC in these patients. Lack of washout or capsule appearance in steatotic livers at MRI may require alternative criteria for the diagnosis of HCC in patients with non-cirrhotic NAFLD.

Future of Treatment for Nonalcoholic Steatohepatitis: Can the Use of Safe, Evidence-Based, Clinically Proven Supplements Provide the Answer to the Unmet Need?

The epidemic of nonalcoholic fatty liver disease (NAFLD) has created a real and unmet therapeutic need. The long regulatory pathway and the focus on selected subsets of patients with established and advanced disease are some of the current obstacles to providing effective treatment for the majority of NAFLD patients. The complexity of the disease pathogenesis, which involves multiple mechanisms, requires targeting of more than one pathway or a combination-based therapy. Although the drugs being developed may prevent progression to cirrhosis or may decrease negative liver outcomes, their effects on cardiometabolic health and cancer prevention remain unknown. Providing expensive compounds to a large proportion of the population for long-term use would place an economic burden on health care providers. Thus, there is a missed opportunity for early intervention in the course of the disease, by providing agents that improve cardiometabolic status and the progression of fatty liver toward steatohepatitis. Several natural supplements have the potential to meet these needs. This review discusses some of the major obstacles to drug development for NASH treatment. Milestones in bringing evidenced-based, scientifically proven, patent-protected, clinically tested, safe compounds to patients with NAFLD or NASH within a relatively short period of time are presented. The regulatory, intellectual property, manufacturing, and clinical development steps, along with applicable timelines, are discussed. These compounds may provide a possible solution to the challenges associated with the treatment of the majority of patients.

Changes in the immune system - the key to diagnostics and therapy of patients with non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is one of the most common pathologies of that organ. The development of the disease involves a variety of mechanisms, including insulin resistance, oxidative stress, endoplasmic reticulum stress, endotoxins from the intestinal flora and genetic predispositions. Additionally, clinical data suggest that the presence of NAFLD is associated with excessive activation of the immune system. For practical purposes, attention should be paid to the moment when the subjects predisposed to NAFLD develop inflammatory infiltration and signs of fibrosis in the liver (non-alcoholic steatohepatitis - NASH). Their presence is an important risk factor for hepatic cirrhosis, hepatic failure, and hepatocellular carcinoma, as well as for the occurrence of cardiovascular events. Regardless of the diagnostic methods used, including laboratory tests and imaging, liver biopsy remains the gold standard to identify and differentiate patients with NAFLD and NASH. The search for other, safer, cheaper and more readily available diagnostic tests is still being continued. Attention has been drawn to the usefulness of markers of immune status of the organism, not only for the diagnosis of NASH, but also for the identification of NAFLD patients at risk of disease progression. Despite the effectiveness of medication, no recommendations have been established for pharmacotherapy of NAFLD. Data indicate the primary need for non-pharmacological interventions to reduce body weight. However, there is evidence of the applicability of certain drugs and dietary supplements, which, by their effect on the immune system, inhibit its excessive activity, thus preventing the progression of NAFLD to NASH.

Nonalcoholic Fatty Liver Disease in Inflammatory Bowel Disease: Prevalence and Risk Factors

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is common in inflammatory bowel diseases (IBD). Herein, NAFLD prevalence and risk factors in a large IBD cohort were evaluated and compared to that of a non-IBD sample.

METHODS

Crohn's disease/ulcerative colitis outpatients referred to IBD service of our Gastroenterology Unit were enrolled. Subjects affected by functional and motor gastrointestinal disorders, in whom IBD was ruled out, referred to general outpatient service in the same area, were considered as nonIBD group. Exclusion criteria were based on previous diagnosis of nonNAFLD chronic liver diseases and secondary causes of fat liver overload. Characteristics of IBD and liver status were collected. Risk factors for metabolic syndrome were analyzed. Ultrasonographic presence and degree of steatosis were assessed. Data were examined by univariate and multivariate analyses.

RESULTS

For this study 465 IBD and 189 non-IBD subjects were consecutively enrolled. NAFLD was found in 28.0% and 20.1% in IBD and non-IBD subjects, respectively (P = 0.04). IBD patients with NAFLD were younger than non-IBD ones. There was no significant difference in steatosis grade and association between NAFLD and IBD behavior, extension, activity, and drugs. In the IBD group, multivariate analysis demonstrated that NAFLD was independently associated to metabolic syndrome (OR=2.24, 95%CI 1.77-28.81), diabetes (OR=1.71, 95%CI 1.43-12.25), fasting blood glucose (OR=1.36, 95%CI 1.13-1.68), and abdominal circumference (OR=1.68, 95%CI 1.15-14.52).

CONCLUSIONS

NAFLD is more common and occurs at a younger age in IBD than in nonIBD subjects. However, further investigation is required to ascertain possible NAFLD pathogenic IBD-related factors other than conventional/metabolic ones. 10.1093/ibd/izy051_video1izy051.video15774874877001.

Omega-3 fatty acids and non-alcoholic fatty liver disease: Evidence of efficacy and mechanism of action

For many years it has been known that high doses of long chain omega-3 fatty acids are beneficial in the treatment of hypertriglyceridaemia. Over the last three decades, there has also been a wealth of in vitro and in vivo data that has accumulated to suggest that long chain omega-3 fatty acid treatment might be beneficial to decrease liver triacylglycerol. Several biological mechanisms have been identified that support this hypothesis; notably, it has been shown that long chain omega-3 fatty acids have a beneficial effect: a) on bioactive metabolites involved in inflammatory pathways, and b) on alteration of nuclear transcription factor activities such as peroxisome proliferator-activated receptors (PPARs), sterol regulatory element-binding protein 1c (SREBP-1c) and carbohydrate-responsive element-binding protein (ChREBP), involved in inflammatory pathways and liver lipid metabolism. Since the pathogenesis of non alcoholic fatty liver disease (NAFLD) begins with the accumulation of liver lipid and progresses with inflammation and then several years later with development of fibrosis; it has been thought in patients with NAFLD omega-3 fatty acid treatment would be beneficial in treating liver lipid and possibly also in ameliorating inflammation. Meta-analyses (of predominantly dietary studies and small trials) have tended to support the assertion that omega-3 fatty acids are beneficial in decreasing liver lipid, but recent randomised controlled trials have produced conflicting data. These trials have suggested that omega-3 fatty acid might be beneficial in decreasing liver triglyceride (docosahexanoic acid also possibly being more effective than eicosapentanoic acid) but not in decreasing other features of steatohepatitis (or liver fibrosis). The purpose of this review is to discuss recent evidence regarding biological mechanisms by which long chain omega-3 fatty acids might act to ameliorate liver disease in NAFLD; to consider the recent evidence from randomised trials in both adults and children with NAFLD; and finally to discuss key 'known unknowns' that need to be considered, before planning future studies that are focussed on testing the effects of omega-3 fatty acid treatment in patients with NAFLD.

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.