Nonalcoholic fatty liver disease as a complication of insulin resistance

Exploring cancer-associated fibroblast-induced resistance to tyrosine kinase inhibitors in hepatoma cells using a liver-on-a-chip model

Liver cancer is a significant global contributor to cancer-related mortality. Despite available targeted therapies, resistance to tyrosine kinase inhibitors (TKIs) like sorafenib and lenvatinib poses a formidable challenge. The tumor microenvironment (TME), inhabited by cancer-associated fibroblasts (CAFs), profoundly influences this resistance. To uncover the mechanisms, a 3D microfluidic chip replicating liver architecture was fabricated to probe the intricate mechanisms of TKI resistance. The chip design mirrors the hexagonal structure of liver lobules, situating liver cancer cells at the core, encircled by fibroblasts, with rigorous assessments confirming biocompatibility and consistent cell growth. After determining the IC50 values of sorafenib and lenvatinib in 2D co-culture, a transwell setup revealed drug resistance development in co-cultured cells. Within the 3D microfluidic chip, live/dead assays highlighted elevated viability under drug exposure, emphasizing fibroblast-driven drug resistance. The study identifies AHSG and CLEC3B as potential mediators of drug resistance in co-culture, significantly upregulated in the co-cultured medium. Functional tests confirmed their roles, as introducing recombinant AHSG and CLEC3B enhanced liver cancer cell resistance to sorafenib and lenvatinib in both 2D and 3D scenarios. In conclusion, by replicating the complex TME using microfluidic technology, this study sheds light on the roles of AHSG and CLEC3B as well as possible approaches for improving the effectiveness of liver cancer treatment.

Application of machine learning in predicting non-alcoholic fatty liver disease using anthropometric and body composition indices

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, which can progress from simple steatosis to advanced cirrhosis and hepatocellular carcinoma. Clinical diagnosis of NAFLD is crucial in the early stages of the disease. The main aim of this study was to apply machine learning (ML) methods to identify significant classifiers of NAFLD using body composition and anthropometric variables. A cross-sectional study was carried out among 513 individuals aged 13 years old or above in Iran. Anthropometric and body composition measurements were performed manually using body composition analyzer InBody 270. Hepatic steatosis and fibrosis were determined using a Fibroscan. ML methods including k-Nearest Neighbor (kNN), Support Vector Machine (SVM), Radial Basis Function (RBF) SVM, Gaussian Process (GP), Random Forest (RF), Neural Network (NN), Adaboost and Naïve Bayes were examined for model performance and to identify anthropometric and body composition predictors of fatty liver disease. RF generated the most accurate model for fatty liver (presence of any stage), steatosis stages and fibrosis stages with 82%, 52% and 57% accuracy, respectively. Abdomen circumference, waist circumference, chest circumference, trunk fat and body mass index were among the most important variables contributing to fatty liver disease. ML-based prediction of NAFLD using anthropometric and body composition data can assist clinicians in decision making. ML-based systems provide opportunities for NAFLD screening and early diagnosis, especially in population-level and remote areas.

Krüppel-like Factor 9 (KLF9) Suppresses Hepatocellular Carcinoma (HCC)-Promoting Oxidative Stress and Inflammation in Mice Fed High-Fat Diet

Obesity, oxidative stress, and inflammation are risk factors for hepatocellular carcinoma (HCC). We examined, in mice, the effects of Krüppel-like factor 9 (KLF9) knockout on: adiposity, hepatic and systemic oxidative stress, and hepatic expression of pro-inflammatory and NOX/DUOX family genes, in a high-fat diet (HFD) context. Male and female Klf9^+/+ (wild type, WT) and Klf9^-/- (knockout, KO) mice were fed HFD (beginning at age 35 days) for 12 weeks, after which liver and adipose tissues were obtained, and serum adiponectin and leptin levels, liver fat content, and markers of oxidative stress evaluated. Klf9^-/- mice of either sex did not exhibit significant alterations in weight gain, adipocyte size, adipokine levels, or liver fat content when compared to WT counterparts. However, Klf9^-/- mice of both sexes had increased liver weight/size (hepatomegaly). This was accompanied by increased hepatic oxidative stress as indicated by decreased GSH/GSSG ratio and increased homocysteine, 3-nitrotyrosine, 3-chlorotyrosine, and 4HNE content. Decreased GSH to GSSG ratio and a trend toward increased homocysteine levels were observed in the corresponding Klf9^-/- mouse serum. Gene expression analysis showed a heightened pro-inflammatory state in livers from Klf9^-/- mice. KLF9 suppresses hepatic oxidative stress and inflammation, thus identifying potential mechanisms for KLF9 suppression of HCC and perhaps cancers of other tissues.

Insulin resistance and the role of gamma-aminobutyric acid

Insulin resistance (IR) is mentioned to be a disorder in insulin ability in insulin-target tissues. Skeletal muscle (SkM) and liver function are more affected by IR than other insulin target cells. SkM is the main site for the consumption of ingested glucose. An effective treatment for IR has two properties: An inhibition of β-cell death and a promotion of β-cell replication. Gamma-aminobutyric acid (GABA) can improve beta-cell mass and function. Multiple studies have shown that GABA decreases IR probably via increase in glucose transporter 4 (GLUT4) gene expression and prevention of gluconeogenesis pathway in the liver. This review focused on the general aspects of IR in skeletal muscle (SkM), liver; the cellular mechanism(s) lead to the development of IR in these organs, and the role of GABA to reduce insulin resistance.

Nutritional supplementation for nonalcohol-related fatty liver disease: a network meta-analysis

BACKGROUND

The prevalence of non-alcohol-related fatty liver disease (NAFLD) varies between 19% and 33% in different populations. NAFLD decreases life expectancy and increases risks of liver cirrhosis, hepatocellular carcinoma, and the requirement for liver transplantation. Uncertainty surrounds relative benefits and harms of various nutritional supplements in NAFLD. Currently no nutritional supplement is recommended for people with NAFLD.

OBJECTIVES

• To assess the benefits and harms of different nutritional supplements for treatment of NAFLD through a network meta-analysis • To generate rankings of different nutritional supplements according to their safety and efficacy SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, Science Citation Index Expanded, Conference Proceedings Citation Index-Science, the World Health Organization International Clinical Trials Registry Platform, and trials registers until February 2021 to identify randomised clinical trials in people with NAFLD.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or status) for people with NAFLD, irrespective of method of diagnosis, age and diabetic status of participants, or presence of non-alcoholic steatohepatitis (NASH). We excluded randomised clinical trials in which participants had previously undergone liver transplantation.

DATA COLLECTION AND ANALYSIS

We performed a network meta-analysis with OpenBUGS using Bayesian methods whenever possible and calculated differences in treatments using hazard ratios (HRs), odds ratios (ORs), and rate ratios with 95% credible intervals (CrIs) based on an available-case analysis, according to National Institute of Health and Care Excellence Decision Support Unit guidance.

MAIN RESULTS

We included in the review a total of 202 randomised clinical trials (14,200 participants). Nineteen trials were at low risk of bias. A total of 32 different interventions were compared in these trials. A total of 115 trials (7732 participants) were included in one or more comparisons. The remaining trials did not report any of the outcomes of interest for this review. Follow-up ranged from 1 month to 28 months. The follow-up period in trials that reported clinical outcomes was 2 months to 28 months. During this follow-up period, clinical events related to NAFLD such as mortality, liver cirrhosis, liver decompensation, liver transplantation, hepatocellular carcinoma, and liver-related mortality were sparse. We did not calculate effect estimates for mortality because of sparse data (zero events for at least one of the groups in the trial). None of the trials reported that they measured overall health-related quality of life using a validated scale. The evidence is very uncertain about effects of interventions on serious adverse events (number of people or number of events). We are very uncertain about effects on adverse events of most of the supplements that we investigated, as the evidence is of very low certainty. However, people taking PUFA (polyunsaturated fatty acid) may be more likely to experience an adverse event than those not receiving an active intervention (network meta-analysis results: OR 4.44, 95% CrI 2.40 to 8.48; low-certainty evidence; 4 trials, 203 participants; direct evidence: OR 4.43, 95% CrI 2.43 to 8.42). People who take other supplements (a category that includes nutritional supplements other than vitamins, fatty acids, phospholipids, and antioxidants) had higher numbers of adverse events than those not receiving an active intervention (network meta-analysis: rate ratio 1.73, 95% CrI 1.26 to 2.41; 6 trials, 291 participants; direct evidence: rate ratio 1.72, 95% CrI 1.25 to 2.40; low-certainty evidence). Data were sparse (zero events in all groups in the trial) for liver transplantation, liver decompensation, and hepatocellular carcinoma. So, we did not perform formal analysis for these outcomes. The evidence is very uncertain about effects of other antioxidants (antioxidants other than vitamins) compared to no active intervention on liver cirrhosis (HR 1.68, 95% CrI 0.23 to 15.10; 1 trial, 99 participants; very low-certainty evidence). The evidence is very uncertain about effects of interventions in any of the remaining comparisons, or data were sparse (with zero events in at least one of the groups), precluding formal calculations of effect estimates. Data were probably because of the very short follow-up period (2 months to 28 months). It takes follow-up of 8 to 28 years to detect differences in mortality between people with NAFLD and the general population. Therefore, it is unlikely that differences in clinical outcomes are noted in trials providing less than 5 to 10 years of follow-up.

AUTHORS' CONCLUSIONS

The evidence indicates considerable uncertainty about effects of nutritional supplementation compared to no additional intervention on all clinical outcomes for people with non-alcohol-related fatty liver disease. Accordingly, high-quality randomised comparative clinical trials with adequate follow-up are needed. We propose registry-based randomised clinical trials or cohort multiple randomised clinical trials (study design in which multiple interventions are trialed within large longitudinal cohorts of patients to gain efficiencies and align trials more closely to standard clinical practice) comparing interventions such as vitamin E, prebiotics/probiotics/synbiotics, PUFAs, and no nutritional supplementation. The reason for the choice of interventions is the impact of these interventions on indirect outcomes, which may translate to clinical benefit. Outcomes in such trials should be mortality, health-related quality of life, decompensated liver cirrhosis, liver transplantation, and resource utilisation measures including costs of intervention and decreased healthcare utilisation after minimum follow-up of 8 years (to find meaningful differences in clinically important outcomes).

Uric acid albumin ratio as a predictive marker of short-term mortality in patients with acute kidney injury

OBJECTIVE

We aimed to investigate uric acid and albumin ratio (UA/A) as a marker of short-term mortality in acute kidney injury (AKI). Both uric acid and albumin are strongly correlated with the development and mortality of AKI.

METHODS

The patients hospitalized from May 2019 to September 2019 for AKI were included in this study. The diagnostic odds ratio (DOR), Youden index (J), and the area under a receiver operating characteristic curve (AUROC) determined a cut-off UA/A ratio for mortality. Cox-regression analysis was performed to identify UA/A as a prognostic marker of the 30-day mortality rate.

RESULTS

A total of 171 patients with an average age of 69.20±13.0 (45.6% women) were included in the study. The average UA/A ratio was 3.3±1.5 mg/g and 2.5±1.0 mg/g in the non-survivor and survivor groups, respectively (P=0.001). The best cut-off UA/A ratio associated with mortality was determined as 2.4 mg/g with a specificity of 52% and a sensitivity of 77% (DOR, 3.6; J, 28.8; AUROC, 0.644). Thirty-day cumulative survival rates of the low and high UA/A ratio groups were 85.9±4.0% and 63.7±5.0%, respectively. The estimated survival times of the low and high UA/A ratio groups were 27.7 days (95% confidence interval [CI], 26.2-29.3) and 23.9 days (95% Cl, 22.0-25.9), respectively.

CONCLUSION

We found a direct correlation between 30-day mortality and UA/A ratio at initial presentation in AKI patients regardless of age, comorbidities, and clinical and laboratory findings, including albuminuria.

Lifestyle modifications for nonalcohol-related fatty liver disease: a network meta-analysis

BACKGROUND

The prevalence of nonalcohol-related fatty liver disease (NAFLD) varies between 19% and 33% in different populations. NAFLD decreases life expectancy and increases the risks of liver cirrhosis, hepatocellular carcinoma, and requirement for liver transplantation. There is uncertainty surrounding the relative benefits and harms of various lifestyle interventions for people with NAFLD.

OBJECTIVES

To assess the comparative benefits and harms of different lifestyle interventions in the treatment of NAFLD through a network meta-analysis, and to generate rankings of the different lifestyle interventions according to their safety and efficacy.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, Conference Proceedings Citation Index - Science, World Health Organization International Clinical Trials Registry Platform, and trials registers until February 2021 to identify randomised clinical trials in people with NAFLD.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or status) in people with NAFLD, whatever the method of diagnosis, age, and diabetic status of participants, or presence of non-alcoholic steatohepatitis (NASH). We excluded randomised clinical trials in which participants had previously undergone liver transplantation.

DATA COLLECTION AND ANALYSIS

We planned to perform a network meta-analysis with OpenBUGS using Bayesian methods and to calculate the differences in treatments using hazard ratios (HRs), odds ratios (ORs), and rate ratios (RaRs) with 95% credible intervals (CrIs) based on an available-participant analysis, according to National Institute of Health and Care Excellence Decision Support Unit guidance. However, the data were too sparse for the clinical outcomes. We therefore performed only direct comparisons (head-to-head comparisons) with OpenBUGS using Bayesian methods.

MAIN RESULTS

We included a total of 59 randomised clinical trials (3631 participants) in the review. All but two trials were at high risk of bias. A total of 33 different interventions, ranging from advice to supervised exercise and special diets, or a combination of these and no additional intervention were compared in these trials. The reference treatment was no active intervention. Twenty-eight trials (1942 participants) were included in one or more comparisons. The follow-up ranged from 1 month to 24 months. The remaining trials did not report any of the outcomes of interest for this review. The follow-up period in the trials that reported clinical outcomes was 2 months to 24 months. During this short follow-up period, clinical events related to NAFLD such as mortality, liver cirrhosis, liver decompensation, liver transplantation, hepatocellular carcinoma, and liver-related mortality were sparse. This is probably because of the very short follow-up periods. It takes a follow-up of 8 years to 28 years to detect differences in mortality between people with NAFLD and the general population. It is therefore unlikely that differences by clinical outcomes will be noted in trials with less than 5 years to 10 years of follow-up. In one trial, one participant developed an adverse event. There were no adverse events in any of the remaining participants in this trial, or in any of the remaining trials, which seemed to be directly related to the intervention.

AUTHORS' CONCLUSIONS

The evidence indicates considerable uncertainty about the effects of the lifestyle interventions compared with no additional intervention (to general public health advice) on any of the clinical outcomes after a short follow-up period of 2 months to 24 months in people with nonalcohol-related fatty liver disease. Accordingly, high-quality randomised clinical trials with adequate follow-up are needed. We propose registry-based randomised clinical trials or cohort multiple randomised clinical trials (a study design in which multiple interventions are trialed within large longitudinal cohorts of participants to gain efficiencies and align trials more closely to standard clinical practice), comparing aerobic exercise and dietary advice versus standard of care (exercise and dietary advice received as part of national health promotion). The reason for the choice of aerobic exercise and dietary advice is the impact of these interventions on indirect outcomes which may translate to clinical benefit. The outcomes in such trials should be mortality, health-related quality of life, decompensated liver cirrhosis, liver transplantation, and resource use measures including costs of intervention and decreased healthcare use after a minimum follow-up of eight years, to find meaningful differences in the clinically important outcomes.

GDF11 rapidly increases lipid accumulation in liver cancer cells through ALK5-dependent signaling

Hepatocellular carcinoma (HCC) is one of the fastest-growing causes of cancer-related mortalities worldwide and this trend is mimicked by the surge of non-alcoholic fatty liver disease (NAFLD). Altered hepatic lipid metabolism promotes HCC development through inflammation and activation of oncogenes. GDF11 is a member of the TGF-β superfamily and recent data have implicated GDF11 as an anti-aging factor that can alleviate high-fat diet induced obesity, hyperglycemia, insulin resistance and NAFLD. However, its role in hepatic lipid metabolism is still not fully delineated. The aim of the present study was to characterize the role of GDF11 in hepatic and HCC cells lipid accumulation. To achieve this, we performed imaging, biochemical, lipidomic, and transcriptomic analyses in primary hepatocytes and in HCC cells treated with GDF11 to study the GDF11-activated signaling pathways. GDF11 treatment rapidly triggered ALK5-dependent SMAD2/3 nuclear translocation and elevated lipid droplets in HCC cells, but not in primary hepatocytes. In HCC cells, ALK5 inhibition hampered GDF11-mediated SMAD2/3 signaling and attenuated lipid accumulation. Using ultra-high-performance liquid chromatography/mass spectrometry, we detected increased accumulation of longer acyl-chain di/tri-acylglycerols and glycerophospholipids. Unbiased transcriptomic analysis identified TGF-β and PI3K-AKT signaling among the top pathways/cellular processes activated in GDF11 treated HCC cells. In summary, GDF11 supplementation promotes pro-lipogenic gene expression and lipid accumulation in HCC cells. Integration of our "omics" data pointed to a GDF11-induced upregulation of de novo lipogenesis through activation of ALK5/SMAD2/3/PI3K-AKT pathways. Thus, GDF11 could contribute to metabolic reprogramming and dysregulation of lipid metabolism in HCC cells, without effects on healthy hepatocytes.

Hepatic Fibrosis Associates With Multiple Cardiometabolic Disease Risk Factors: The Framingham Heart Study

BACKGROUND AND AIMS

NAFLD is increasing in prevalence and will soon be the most common chronic liver disease. Liver stiffness, as assessed by vibration-controlled transient elastography (VCTE), correlates with hepatic fibrosis, an important predictor of liver-related and all-cause mortality. Although liver fat is associated with cardiovascular risk factors, the association between hepatic fibrosis and cardiovascular risk factors is less clear.

APPROACH AND RESULTS

We performed VCTE, assessing controlled attenuation parameter (CAP; measure of steatosis) and liver stiffness measurement (LSM) in 3,276 Framingham Heart Study adult participants (53.9% women, mean age 54.3 ± 9.1 years) presenting for a routine study visit. We performed multivariable-adjusted logistic regression models to determine the association between LSM and obesity-related, vascular-related, glucose-related, and cholesterol-related cardiovascular risk factors. The prevalence of hepatic steatosis (CAP ≥ 290 dB/m) was 28.8%, and 8.8% had hepatic fibrosis (LSM ≥ 8.2 kPa). Hepatic fibrosis was associated with multiple cardiovascular risk factors, including increased odds of obesity (OR, 1.82; 95% CI, 1.35-2.47), metabolic syndrome (OR, 1.49; 95% CI 1.10-2.01), diabetes (OR, 2.67; 95% CI, 1.21-3.75), hypertension (OR, 1.52; 95% CI, 1.15-1.99), and low high-density lipoprotein cholesterol (OR, 1.47; 95% CI, 1.09-1.98), after adjustment for age, sex, smoking status, alcohol drinks/week, physical activity index, aminotransferases, and CAP.

CONCLUSIONS

In our community-based cohort, VCTE-defined hepatic fibrosis was associated with multiple cardiovascular risk factors, including obesity, metabolic syndrome, diabetes, hypertension, and high-density lipoprotein cholesterol, even after accounting for covariates and CAP. Additional longitudinal studies are needed to determine if hepatic fibrosis contributes to incident cardiovascular disease risk factors or events.

The Effect of Curcumin Phytosome on the Treatment of Patients with Non-alcoholic Fatty Liver Disease: A Double-Blind, Randomized, Placebo-Controlled Trial

Non-alcoholic fatty liver disease (NAFLD) is a global health problem with increasing prevalence among overweight and obese patients. It is strongly associated with conditions of insulin resistance including type 2 diabetes mellitus (T2DM) and obesity. It has detrimental consequences ranged from simple steatosis to irreversible hepatic fibrosis and cirrhosis. Curcumin is a dietary polyphenol with potential effect in improving NAFLD. Therefore, the aim of this trial was to examine the effect of curcumin supplementation on various aspects of NAFLD. In this trial, a total number of 80 patients were randomised to receive either curcumin at 250 mg daily or placebo for 2 months. Lipid profiles, hepatic enzymes, anthropometric indices and hepatic fat mass were assessed at the baseline and the end of the trial, and compared within the groups. The grade of hepatic steatosis, and serum aspartate aminotransferase (AST) levels were significantly reduced in the curcumin group (p = 0.015 and p = 0.007, respectively) compared to the placebo. There was also a significant reduction in high density lipoprotein (HDL) levels and anthropometric indices in both groups with no significant differences between the two groups. Low dose phospholipid curcumin supplementation each day for 2 months showed significant reduction in hepatic steatosis and enzymes in patients with NAFLD compared to placebo. Further studies of longer duration and higher dosages are needed to assess its effect on other parameters of NAFLD including cardiovascular risk.

Exploring the Impact of Obesity on Health Care Resources and Coding in the Acute Hospital Setting: A Feasibility Study

Obesity is costly, yet there have been few attempts to estimate the actual costs of providing hospital care to the obese inpatient. This study aimed to test the feasibility of measuring obesity-related health care costs and accuracy of coding data for acute inpatients. A prospective observational study was conducted over three weeks in June 2018 in a single orthopaedic ward of a metropolitan tertiary hospital in Queensland, Australia. Demographic data, anthropometric measurements, clinical characteristics, cost of hospital encounter and coding data were collected. Complete demographic, anthropometric and clinical data were collected for all 18 participants. Hospital costing reports and coding data were not available within the study timeframe. Participant recruitment and data collection were resource-intensive, with mobility assistance required to obtain anthropometric measurements in more than half of the participants. Greater staff time and costs were seen in participants with obesity compared to those without obesity (obesity: body mass index ≥ 30), though large standard deviations indicate wide variance. Data collected suggest that obesity-related cost and resource use amongst acute inpatients require further exploration. This study provides recommendations for protocol refinement to improve the accuracy of data collected for future studies measuring the actual cost of providing hospital care to obese inpatients.

GDF11 induces mild hepatic fibrosis independent of metabolic health

BACKGROUND & AIMS

Growth Differentiation Factor 11 (GDF11) is an anti-aging factor, yet its role in liver diseases is not established. We evaluated the role of GDF11 in healthy conditions and in the transition from non-alcoholic fatty liver disease (NAFLD) to non-alcoholic steatohepatitis (NASH).

RESULTS

GDF11 mRNA levels positively correlated with NAFLD activity score and with CPT1, SREBP, PPARγ and Col1A1 mRNA levels, and associated to portal fibrosis, in morbidly obese patients with NAFLD/NASH. GDF11-treated mice showed mildly exacerbated hepatic collagen deposition, accompanied by weight loss and without changes in liver steatosis or inflammation. GDF11 triggered ALK5-dependent SMAD2/3 nuclear translocation and the pro-fibrogenic activation of HSC.

CONCLUSIONS

GDF11 supplementation promotes mild liver fibrosis. Even considering its beneficial metabolic effects, caution should be taken when considering therapeutics that regulate GDF11.

METHODS

We analyzed liver biopsies from a cohort of 33 morbidly obese adults with NAFLD/NASH. We determined the correlations in mRNA expression levels between GDF11 and genes involved in NAFLD-to-NASH progression and with pathological features. We also exposed wild type or obese mice with NAFLD to recombinant GDF11 by daily intra-peritoneal injection and monitor the hepatic pathological changes. Finally, we analyzed GDF11-activated signaling pathways in hepatic stellate cells (HSC).

Donor Fecal Microbiota Transplantation Alters Gut Microbiota and Metabolites in Obese Individuals With Steatohepatitis

The intestinal microbiota has been linked to the development and prevalence of steatohepatitis in humans. Interestingly, steatohepatitis is significantly lower in individuals taking a plant-based, low-animal-protein diet, which is thought to be mediated by gut microbiota. However, data on causality between these observations in humans is scarce. In this regard, fecal microbiota transplantation (FMT) using healthy donors is safe and is capable of changing microbial composition in human disease. We therefore performed a double-blind randomized controlled proof-of-principle study in which individuals with hepatic steatosis on ultrasound were randomized to two study arms: lean vegan donor (allogenic n = 10) or own (autologous n = 11) FMT. Both were performed three times at 8-week intervals. A liver biopsy was performed at baseline and after 24 weeks in every subject to determine histopathology (Nonalcoholic Steatohepatitis Clinical Research Network) classification and changes in hepatic gene expression based on RNA sequencing. Secondary outcome parameters were changes in intestinal microbiota composition and fasting plasma metabolomics. We observed a trend toward improved necro-inflammatory histology, and found significant changes in expression of hepatic genes involved in inflammation and lipid metabolism following allogenic FMT. Intestinal microbial community structure changed following allogenic FMT, which was associated with changes in plasma metabolites as well as markers of . Conclusion: Allogenic FMT using lean vegan donors in individuals with hepatic steatosis shows an effect on intestinal microbiota composition, which is associated with beneficial changes in plasma metabolites and markers of steatohepatitis.

Nonalcoholic Fatty Liver Disease: An Important Consideration for Primary Care Providers in Hawai'i

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. NAFLD is a broad term for both non-alcoholic fatty liver (NAFL), which describes simple fatty liver without inflammation, and non-alcoholic steatohepatitis (NASH), the more severe phenotype with hepatocellular inflammation. The population of Hawai'i is particularly vulnerable to the NAFLD and obesity epidemics due to its large proportions of high-risk ethnic minorities exposed to varying degrees of westernization. Unfortunately, primary care providers (PCPs) often face a lack of awareness on the diagnosis and disease spectrum of NAFLD. Early initiation of treatment for NAFLD is crucial to slow its progression and prevent liver-related morbidity and mortality. This review aims to raise awareness for NAFLD among PCPs in Hawai'i by summarizing the disease's epidemiology, diagnosis, and treatment. The diagnostic workup of NAFLD in the primary care setting involves exclusion of other liver disease etiologies and staging assessment of fibrosis and steatosis through non-invasive means such as serum biomarkers or elastography. Patients with overt signs and symptoms of cirrhosis or a high likelihood of advanced hepatic fibrosis should be referred to liver disease specialists. The role of PCPs in NAFLD management involves facilitating weight loss through therapeutic lifestyle modifications and treatment of comorbid cardiovascular conditions. Evidence-based pharmacologic therapies for NAFLD are available, such as vitamin E and pioglitazone, with more currently in development.

Triterpenic acids-enriched fraction from Cyclocarya paliurus attenuates insulin resistance and hepatic steatosis via PI3K/Akt/GSK3β pathway

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent form of chronic liver diseases. Cyclocarya paliurus (C. paliurus), an edible and medicinal plant in Chinese folk, has been demonstrated to ameliorate diabetes, obesity and lipid metabolism disorders. However, its effects on NAFLD and its potential molecular mechanism have not been clearly expounded.

PURPOSE

The present study was designed to explore the therapeutic potential of triterpenic acids-enriched fraction from C. paliurus (CPT), as well as its underlying mechanism in vivo and in vitro models of NAFLD.

METHODS

The metabolic effects and possible molecular mechanism of CPT were examined using HepG2 cells and primary hepatocytes (isolated from C57BL/6 J mice) models of fatty liver induced by palmitic acid (PA) and a high fat diet mouse model.

RESULTS

In high fat diet-induced C57BL/6 J mice, CPT significantly reduced liver weight index, serum alanine transaminase (ALT), aspartate transaminase (AST), triacylglycerol (TG), total cholesterol (TC) and hepatic TG, TC levels. Moreover, CPT dramatically decreased the contents of blood glucose, insulin, and insulin resistance (HOMA-IR) index. Meanwhile, CPT significantly increased the tyrosine phosphorylation level of IRS and the uptake of 2-deoxyglucose (2DG) in PA-induced HepG2 cells and primary hepatocytes fatty liver models. Furthermore, in PA-induced HepG2 cells and primary hepatocytes, CPT significantly decreased the number of lipid droplets and intracellular TG content. In addition, mechanism investigation showed that CPT increased the phosphorylation of phosphoinositide 3-kinase (PI3K), protein kinase B (Akt) and glycogen synthase-3β (GSK3β) in vivo and in vitro models, which were abrogated by PI3K inhibitor LY294002 in vitro models.

CONCLUSION

These findings indicate that CPT may exert the therapeutic effects on NAFLD via regulating PI3K/Akt/GSK3β pathway.

Histological effects and pharmacokinetics of lipopolysaccharide derived from Porphyromonas gingivalis on rat maxilla and liver concerning with progression into non-alcoholic steatohepatitis

BACKGROUND

Non-alcoholic steatohepatitis (NASH) is one of the chronic liver diseases that can develop into hepatocirrhosis. The purpose of the present study was to investigate the impact of lipopolysaccharide (LPS) from Porphyromonas gingivalis (P. gingivalis) on NASH onset, and to determine the biodistribution of double-radiolabeled LPS (R-LPS) biosynthesized in P. gingivalis.

METHODS

Rats fed a basal diet (BD) or a high-fat diet (HD) were injected with P. gingivalis-LPS or R-LPS into the palatine gingiva around the right maxillary first molar, and were classified into the following 4 groups: BD/LPS (-), BD/LPS (+), HD/LPS (-), and HD/LPS (+) or 2 groups: BD/R-LPS and HD/R-LPS.

RESULTS

Inflammation in the gingiva of the LPS (+) groups progressed significantly more than the LPS (-) groups. Furthermore, in the HD/LPS (+) liver, histologic analysis confirmed the presence of NASH, characterized by large fat droplets, ballooning degeneration, and infiltration of inflammatory cells. When ³ H, ¹⁴ C-R-LPS was injected into the palatine gingiva, radioactivity in the right palatal mucosa of HD/R-LPS rats was the highest in comparison with other regions and was significantly elevated after 24 hours compared to BD/R-LPS rats. Autoradiographic analysis of the maxilla showed distributions from the palatal mucosa to the hard palate and the interdental region. Radioactivity in organs of both BD/R-LPS and HD/R-LPS rats were mostly localized to the liver even after 24 hours.

CONCLUSION

The present study suggests that the transfer of P. gingivalis-LPS from the oral cavity to the liver plays an important role in disease exacerbation of NASH.

Association Between Serum CK-18 Levels and the Degree of Liver Damage in Fructose-Induced Metabolic Syndrome

BACKGROUND

The pathogenesis of nonalcoholic fatty liver disease as a component of metabolic syndrome (MetS) involves the activation of apoptosis in steatotic hepatocytes. Caspase-generated fragments such as cytokeratin-18 (CK-18) in patients with various hepatic impairments are investigated as markers for diagnosis and assessment of disease severity. The goal of the study was to capture early biomarkers of apoptosis and elucidate their role in assessing the presence and extent of hepatic damage in a MetS model.

MATERIALS AND METHODS

We used male Wistar rats, divided into two groups (n = 7): control and high-fructose drinking (HFD) (35% fructose corn syrup for 16 weeks). Metabolic disorders and liver damage were studied by histochemistry (hematoxylin and eosin), immunohistochemical, immunological, and biochemical testing.

RESULTS

Our results showed significant increase in liver and serum levels of CK-18 and pro/antiapoptotic Bax/Bcl2 ratio, and decreased levels of HMGB1 (marker of necrosis) in the HFD group when compared with the control. All HFD rats developed obesity, hyperglycemia, hepatomegaly, microvesicular steatosis, an imbalance in hepatic antioxidative defense by measuring malondialdehyde and sulfhydryl groups (SH) with no inflammation and fibrosis, elevated serum levels of triglycerides, tumor necrosis factor alpha (TNF-α), and C-reactive protein without changes in serum aminotransferase levels relative to the control group. As a result of the applied regression analysis, we have determined that the variables TNF-α (0.92) and SH (0.659) have a strong complex effect on hepatic CK-18 levels with predicted value of the model R = 0.9.

CONCLUSION

The elevated CK-18 serum levels in the HFD group and their association with the histological changes in the liver and biochemical indicators demonstrate the key role of apoptosis in the pathogenesis of HFD-induced liver damage and the reliability of CK-18 as a biomarker for noninvasive assessment of liver damages in MetS.

A Case of Concomitant Obstructive Sleep Apnea and Non-Alcoholic Steatohepatitis Treated With CPAP Therapy

Obstructive sleep apnea syndrome is a disorder of sleep breathing that is a result of recurrent and intermittent hypoxia during sleep induced by the repeated partial or complete collapse of the upper airway, eventually causing chronic intermittent hypoxia. Non-alcoholic fatty liver disease is divided into non-alcoholic fatty liver and non-alcoholic steatohepatitis. Animal and human studies showed that obesity is associated with chronic liver hypoxia, even in the presence of systemic normoxia causing inflammation and release of cytokines. A "two-hit" model has been proposed. The first hit is characterized by insulin resistance and excess hepatic lipid accumulation secondary to abnormal fatty acid metabolism. Oxidative stress and inflammation are thought to comprise the second hit. Gold standard for the diagnosis of non-alcoholic steatohepatitis is a liver biopsy. Many clinical scores and non-invasive tools are used for the diagnosis of non-alcoholic steatohepatitis. Conservative management with lifestyle modifications including diet, exercise and weight loss remains the therapy of choice today. We present a case report of a 39-year-old man who was diagnosed with concomitant non-alcoholic steatohepatitis and severe obstructive sleep apnea. He was started treatment with continuous positive airway pressure and demonstrated excellent adherence to therapy for 6 years, with concomitant obstructive sleep apnea and non-alcoholic steatohepatitis which reversed with prolonged optimal continuous positive airway pressure therapy. Physical examination remained unremarkable except for morbid obesity. His abdominal girth, as well as body mass index, remained unchanged. After 6 years of optimal continuous positive airway pressure therapy, liver enzymes and relevant lipid panel normalized, suggesting reversal of non-alcoholic steatohepatitis.

Dietary Flavonoids in the Prevention of T2D: An Overview

Type 2 diabetes (T2D) is a progressive metabolic disease that is increasing in prevalence globally. It is well established that insulin resistance (IR) and a progressive decline in functional β-cell mass are hallmarks of developing T2D. Obesity is a leading pathogenic factor for developing IR. Constant IR will progress to T2D when β-cells are unable to secret adequate amounts of insulin to compensate for decreased insulin sensitivity. Recently, a considerable amount of research has been devoted to identifying naturally occurring anti-diabetic compounds that are abundant in certain types of foods. Flavonoids are a group of polyphenols that have drawn great interest for their various health benefits. Results from many clinical and animal studies demonstrate that dietary intake of flavonoids might be helpful in preventing T2D, although cellular and molecular mechanisms underlying these effects are still not completely understood. This review discusses our current understanding of the pathophysiology of T2D and highlights the potential anti-diabetic effects of flavonoids and mechanisms of their actions.

Sex disparity in viral load, inflammation and liver damage in transgenic mice carrying full hepatitis B virus genome with the W4P mutation in the preS1 region

AIM

To study sex disparity in susceptibility to hepatocellular carcinoma (HCC), we created a transgenic mouse model that expressed the full hepatitis B virus (HBV) genome with the W4P mutation.

METHODS

Transgenic mice were generated by transferring the pHY92-1.1x-HBV-full genome plasmid (genotype A2) into C57Bl/6N mice. We compared serum levels of hepatitis B surface antigen (HBsAg), interleukin (IL)-6, and the liver enzymes alanine aminotransferase (ALT) and aspartate transaminase (AST), as well as liver histopathological features in male and female transgenic (W4P TG) mice and in nontransgenic littermates of 10 mo of age.

RESULTS

W4P TG males exhibited more pronounced hepatomegaly, significantly increased granule generation in liver tissue, elevated HBsAg expression in the liver and serum, and higher serum ALT and IL-6 levels compared to W4P TG females or littermate control groups.

CONCLUSION

Together, our data indicate that the W4P mutation in preS1 may contribute to sex disparity in susceptibility to HCC by causing increased HBV virion replication and enhanced IL-6-mediated inflammation in male individuals. Additionally, our transgenic mouse model that expresses full HBV genome with the W4P mutation in preS1 could be effectively used for the studies of the progression of liver diseases, including HCC.

Combination of PNPLA3 and TLL1 polymorphism can predict advanced fibrosis in Japanese patients with nonalcoholic fatty liver disease

BACKGROUND

Hepatic fibrosis is an independent risk factor for mortality and liver-related events in patients with nonalcoholic fatty liver disease (NAFLD). PNPLA3 rs738409 has been associated with fibrosis in viral and non-viral hepatitis. TLL1 rs17047200 also has been associated with developing hepatocellular carcinoma probably via hepatic fibrogenesis. We estimated the impact of these genetic polymorphisms on hepatic fibrosis in Japanese patients with NAFLD.

METHODS

We analyzed the association between these genetic variants and the backgrounds of 817 individuals who received health checkups (health check cohort) from 2012 to 2014. Then, we investigated the relationship between genetic variants and liver histology in 258 consecutive patients with biopsy-proven NAFLD in Japan (NAFLD cohort) from 2012 to 2017 (UMIN000027399).

RESULTS

The prevalence of PNPLA3 CG/GG in the NAFLD cohort was higher than that in the health check cohort (p < 0.001). The prevalence of patients with advanced fibrosis (stages 3-4) was higher for PNPLA3 genotype CG/GG than CC (p = 0.048) and for TLL1 genotype AT/TT than AA (p = 0.044). The high-risk group which had at least two risk alleles of these variants was more likely to have advanced fibrosis (p = 0.004). Multivariate analysis identified body mass index [odds ratio (OR) 1.123, serum AST (OR 1.037, p = 0.004], serum albumin (OR 0.247, p = 0.032), and genetic high risk (OR 2.632, p = 0.026) as predictors of advanced fibrosis.

CONCLUSIONS

In Japanese patients with NAFLD, individuals with risk alleles of PNPLA3 and TLL1 may have a risk of advanced fibrosis.

Involvement of Porphyromonas gingivalis in the progression of non-alcoholic fatty liver disease

BACKGROUND AND AIMS

The risk factors in the progression of nonalcoholic fatty liver disease (NAFLD) have not been fully clarified. Porphyromonas gingivalis (P.g) has been considered to be a confounding risk factor for systemic diseases. We aimed to evaluate the effect of P.g infection on risk of progression to NASH.

METHODS

(1) Serum IgG antibody titers against P.g fimbriae (fimA) in 200 biopsy-proven NAFLD patients were measured by ELISA and compared with histological findings. (2) C57BL/6J mice were fed a control diet (CD) or high-fat diet (HFD) with or without P.g-odontogenic infection and analyzed histologically. Mouse livers were analyzed using CE-TOFMS and LC-TOFMS.

RESULTS

(1) A significant correlation between fibrosis progression and antibody titers against P.g possessing fimA type 4 was identified (P = 0.0081). Multivariate analysis identified older age and type 4 P.g-positivity as risk factors for advanced fibrosis. (2) Fibrosis and steatosis were more severe in HFD P.g(+) mice compared with HFD P.g(-) mice. In metabolome analysis, fatty acid metabolism was significantly disrupted with HFD in P.g-infected mouse livers. Monounsaturated/saturated fatty acid ratios were significantly higher in the HFD P.g(+) group than in the HFD P.g(-) group (P < 0.05). Moreover, expression levels of SCD1 and ELOVL6 were significantly reduced.

CONCLUSIONS

These results suggest that P.g infection is an important risk factor for pathological progression in NAFLD. Increase in the monounsaturated/saturated fatty acid ratio may be an important change that facilitates progression of NAFLD.

Linking Nonalcoholic Fatty Liver Disease to Hepatocellular Carcinoma: From Bedside to Bench and Back

Aims and background

Nonalcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC) are two major causes of liver disease worldwide. Epidemiological and clinical data have clearly demonstrated that NAFLD and its associated metabolic abnormalities are a risk factor for HCC. Traditionally, the mechanisms whereby NAFLD acts as a risk for HCC are believed to include replicative senescence of steatotic hepatocytes and compensatory hyperplasia of progenitor cells as a reaction to chronic hepatic injury. Recent years have witnessed significant advances in our understanding of the mechanisms underlying the link between NAFLD and HCC.

Methods

In the present review, we provide an update on the pathophysiological pathways linking NAFLD and its associated metabolic derangements to malignant hepatic transformation, with a special focus on insulin resistance, adipokines, inflammation, and angiogenesis. We will also discuss the potential therapeutic implications that such molecular links carry.

Results

Although treating NAFLD could reduce the risk of malignant hepatic transformation, no long-term studies focusing on this issue have been conducted thus far. Insulin resistance, inflammation as well as derangements in adipokines and angiogenic factors associated with NAFLD are closely intertwined with the risk of developing HCC.

Conclusions

Traditional therapeutic approaches in NAFLD including metformin and statins may theoretically reduce the risk of HCC by acting on common pathophysiological pathways shared by NAFLD and HCC.

Novel SIRT1 activator MHY2233 improves glucose tolerance and reduces hepatic lipid accumulation in db/db mice

The NAD⁺-dependent deacetylase SIRT1, which is associated with the improvement of metabolic syndromes, such as type 2 diabetes, is a well-known longevity-related gene. Several in vitro and in vivo studies have shown the known protective effects of SIRT1 activators, such as resveratrol and SRT1720, on diabetes- or obesity-induced fatty liver and insulin resistance. Here, we newly synthesized 18 benzoxazole hydrochloride derivatives based on the structure of resveratrol and SRT1720. We performed an in vitro SIRT1 activity assay to identify the strongest SIRT1 activator. The assay confirmed MHY2233 to be the strongest SIRT1 activator (1.5-fold more potent than resveratrol), and docking simulation showed that the binding affinity of MHY2233 was higher than that of resveratrol and SRT1720. To investigate its beneficial effects, db/db mice were orally administered MHY2233 for 1 month, and various metabolic parameters were assessed in the serum and liver tissues. MHY2233 markedly ameliorated insulin signaling without affecting body weight in db/db mice. In particular, the mRNA expression of lipogenic genes, such as acetyl CoA carboxylase, fatty acid synthase, and sterol regulatory element-binding protein, which increased in db/db mice, decreased following oral treatment with MHY2233. In conclusion, the novel SIRT1 activator MHY2233 reduced lipid accumulation and improved insulin resistance. This finding may contribute toward therapeutic approaches for fatty liver disease and glucose tolerance.

Effect of CPAP therapy on liver disease in patients with OSA: a review

Obstructive sleep apnea (OSA) may play an important role in the progression of nonalcoholic fatty liver disease (NAFLD).The effect of continuous positive airway pressure (CPAP) treatment, the first-line therapy for OSA, on liver disease in OSA patients is still debated. We provide this review of previous studies to summarize the effects of CPAP treatment on liver disease in OSA patients in aspects of liver function, liver steatosis, fibrosis, and incidence of liver disease. CPAP treatment may be beneficial to liver disease in subjects with OSA independent of metabolic risk factors, but a sufficiently long therapeutic duration (perhaps greater than 3 months) may be needed to achieve these positive effects. Though the mechanism of impact of CPAP treatment on liver in OSA patients is unclear, the influence of CPAP treatment on the factors of the "Two-hit" hypothesis (insulin resistance, fatty acids dysregulation, oxidative stress, and inflammation) may be a reasonable explanation.

Clinical importance of epicardial adipose tissue

Different visceral fat compartments have several systemic effects and may play a role in the development of both insulin resistance and cardiovascular diseases. In the last couple of years special attention has been paid to the epicardial adipose tissue (EAT), which can be quantified by non-invasive cardiac imaging techniques. The epicardial fat is a unique fat compartment between the myocardium and the visceral pericardium sharing a common embryologic origin with the visceral fat depot. Epicardial adipose tissue has several specific roles, and its local effects on cardiac function are incorporated in the complex pathomechanism of coronary artery disease. Importantly, EAT may produce several adipocytokines and chemokines that may influence - through paracrine and vasocrine effects - the development and progression of coronary atherosclerosis. Epicardial adipose tissue volume has a relatively strong genetic dependence, similarly to other visceral fat depots. In this article, the anatomical and physiological as well as pathophysiological characteristics of the epicardial fat compartment are reviewed.

Pharmacological interventions for non-alcohol related fatty liver disease (NAFLD): an attempted network meta-analysis

BACKGROUND

Non-alcohol related fatty liver disease (commonly called non-alcoholic fatty liver disease (NAFLD)) is liver steatosis in the absence of significant alcohol consumption, use of hepatotoxic medication, or other disorders affecting the liver such as hepatitis C virus infection, Wilson's disease, and starvation. NAFLD embraces the full spectrum of disease from pure steatosis (i.e. uncomplicated fatty liver) to non-alcoholic steatohepatitis (NASH), via NASH-cirrhosis to cirrhosis. The optimal pharmacological treatment for people with NAFLD remains uncertain.

OBJECTIVES

To assess the comparative benefits and harms of different pharmacological interventions in the treatment of NAFLD through a network meta-analysis and to generate rankings of the available pharmacological treatments according to their safety and efficacy. However, it was not possible to assess whether the potential effect modifiers were similar across different comparisons. Therefore, we did not perform the network meta-analysis, and instead, assessed the comparative benefits and harms of different interventions using standard Cochrane methodology.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, Science Citation Index Expanded, the World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.com to August 2016.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or publication status) in participants with NAFLD. We excluded trials which included participants who had previously undergone liver transplantation. We considered any of the various pharmacological interventions compared with each other or with placebo or no intervention.

DATA COLLECTION AND ANALYSIS

We calculated the odds ratio (OR) and rate ratio with 95% confidence intervals (CI) using both fixed-effect and random-effects models based on an available participant analysis with Review Manager. We assessed risk of bias according to the Cochrane risk of bias tool, controlled risk of random errors with Trial Sequential Analysis, and assessed the quality of the evidence using GRADE.

MAIN RESULTS

We identified 77 trials including 6287 participants that met the inclusion criteria of this review. Forty-one trials (3829 participants) provided information for one or more outcomes. Only one trial was at low risk of bias in all domains. All other trials were at high risk of bias in one or more domains. Overall, all the evidence was very low quality. Thirty-five trials included only participants with non-alcohol related steatohepatitis (NASH) (based on biopsy confirmation). Five trials included only participants with diabetes mellitus; 14 trials included only participants without diabetes mellitus. The follow-up in the trials ranged from one month to 24 months.We present here only the comparisons of active intervention versus no intervention in which two or more trials reported at least one of the following outcomes: mortality at maximal follow-up, serious adverse events, and health-related quality of life, the outcomes that determine whether a treatment should be used. Antioxidants versus no interventionThere was no mortality in either group (87 participants; 1 trial; very low quality evidence). None of the participants developed serious adverse events in the trial which reported the proportion of people with serious adverse events (87 participants; 1 trial; very low quality evidence). There was no evidence of difference in the number of serious adverse events between antioxidants and no intervention (rate ratio 0.89, 95% CI 0.36 to 2.19; 254 participants; 2 trials; very low quality evidence). None of the trials reported health-related quality of life. Bile acids versus no interventionThere was no evidence of difference in mortality at maximal follow-up (OR 5.11, 95% CI 0.24 to 107.34; 659 participants; 4 trials; very low quality evidence), proportion of people with serious adverse events (OR 1.56, 95% CI 0.84 to 2.88; 404 participants; 3 trials; very low quality evidence), or the number of serious adverse events (rate ratio 1.01, 95% CI 0.66 to 1.54; 404 participants; 3 trials; very low quality evidence) between bile acids and no intervention. None of the trials reported health-related quality of life. Thiazolidinediones versus no interventionThere was no mortality in either group (74 participants; 1 trial; very low quality evidence). None of the participants developed serious adverse events in the two trials which reported the proportion of people with serious adverse events (194 participants; 2 trials; very low quality evidence). There was no evidence of difference in the number of serious adverse events between thiazolidinediones and no intervention (rate ratio 0.25, 95% CI 0.06 to 1.05; 357 participants; 3 trials; very low quality evidence). None of the trials reported health-related quality of life. Source of fundingTwenty-six trials were partially- or fully-funded by pharmaceutical companies that would benefit, based on the results of the trial. Twelve trials did not receive any additional funding or were funded by parties with no vested interest in the results. The source of funding was not provided in 39 trials.

AUTHORS' CONCLUSIONS

Due to the very low quality evidence, we are very uncertain about the effectiveness of pharmacological treatments for people with NAFLD including those with steatohepatitis. Further well-designed randomised clinical trials with sufficiently large sample sizes are necessary.

TRPV4 activation of endothelial nitric oxide synthase resists nonalcoholic fatty liver disease by blocking CYP2E1-mediated redox toxicity

NAFLD is a clinically progressive disease with steatosis, inflammation, endothelial dysfunction and fibrosis being the stages where clinical intervention becomes necessary. Lack of early biomarkers and absence of a FDA approved drug obstructs efforts for effective treatment. NAFLD progression is strongly linked to a balance between liver injury, tissue regeneration and the functioning of endogenous defense mechanisms. The failure of the defense pathways to resist the tissue damage arising from redox stress, one of the "multiple hits" in disease progression, give rise to heightened inflammation and occasional fibrosis. We introduce an endogenous defense mechanism in the liver that is mediated by TRPV4, a transient receptor potential calcium-permeable ion channel that responds to the cytotoxic liver environment and negatively regulates CYP2E1, a cytochrome p450 enzyme. Using Trpv4-/- mice and cultured primary cells, we show that TRPV4 is activated both by damage associated molecular pattern HMGB1 and collagen in diseased Kupffer cells that in turn activate the endothelial NOS (NOS3) to release nitric oxide (NO). The diffusible NO acts in a paracrine fashion in neighboring hepatocytes to deactivate the redox toxicity induced by CYP2E1. We also find that CYP2E1-mediated TRPV4 repression in late stages causes an unrestricted progression of disease. Thus, TRPV4 functions as a sensor of cell stress in the diseased fatty liver and constitutes an endogenous defense molecule, a novel concept with potential for therapeutic approaches against NAFLD, perhaps also against hepatic drug toxicity in general.

Porphyromonas gingivalis induced periodontitis exacerbates progression of non-alcoholic steatohepatitis in rats

Non-alcoholic steatohepatitis (NASH) is a chronic liver disease that can develop into hepatocirrhosis and hepatic carcinoma. In recent years, epidemiological and animal studies have reported that Porphyromonas gingivalis (P. gingivalis), a known periodontopathic bacteria, is closely related to NASH. However, previous studies could not demonstrate a direct relationship between periodontitis, P. gingivalis infection, and NASH. The purpose of the present study was to examine the impact of P. gingivalis-associated periodontitis on the onset and progression of NASH. Forty-two male Wistar rats were used in this study. Rats were fed a high-fat diet (HFD) for 12 weeks in order to induce fatty liver. At 4 weeks from the start of feeding, the animals were performed ligature placement around the maxillary first molar tooth in order to induce experimental periodontitis, and then a P. gingivalis slurry was applied around the ligature twice in a week for 8 weeks (HFD/Pg(+) group). Controls were given the slurry without P. gingivalis after ligature placement using the same protocol (HFD/Pg(-) group). Significant increases in alveolar bone resorption and inflammation in periodontal tissue around the molar tooth in the HFD/Pg(+) group were observed when compared with the HFD/Pg(-) group. Moreover, histological images showing NASH characterized by perivenular lipid deposition including big fatty drops, ballooning degeneration, and focal necrosis with inflammatory cells were confirmed in the liver of rats in the HFD/Pg(+) group. Significant increases in alanine aminotransaminase, aspartate aminotransferase, and C-reactive protein levels were observed in the HFD/Pg(+) group. Furthermore, endotoxin levels in serum in the HFD/Pg(+) group were significantly higher than those in the HFD/Pg(-) group. The present study demonstrated that experimental periodontitis induced by P. gingivalis led to the progression of NASH in rats with fatty liver. Increased levels of endotoxin derived from P. gingivalis infection appear to play a considerable role in the progression of NASH.

Hepatic glucose utilization in hepatic steatosis and obesity

Hepatic steatosis is associated with obesity and insulin resistance. Whether hepatic glucose utilization rate (glucose phosphorylation rate; MRglu) is increased in steatosis and/or obesity is uncertain. Our aim was to determine the separate relationships of steatosis and obesity with MRglu. Sixty patients referred for routine PET/CT had dynamic PET imaging over the abdomen for 30 min post-injection of F-18-fluorodeoxyglucose (FDG), followed by Patlak-Rutland graphical analysis of the liver using abdominal aorta for arterial input signal. The plot gradient was divided by the intercept to give hepatic FDG clearance normalized to hepatic FDG distribution volume (ml/min per 100 ml) and multiplied by blood glucose to give hepatic MRglu (μmol/min per 100 ml). Hepatic steatosis was defined as CT density of ≤40 HU measured from the 60 min whole body routine PET/CT and obesity as body mass index of ≥30 kg/m² Hepatic MRglu was higher in patients with steatosis (3.3±1.3 μmol/min per 100 ml) than those without (1.7±1.2 μmol/min per 100 ml; P<0.001) but there was no significant difference between obese (2.5±1.6 μmol/min per 100 ml) and non-obese patients (2.1±1.3 μmol/min per 100 ml). MRglu was increased in obese patients only if they had steatosis. Non-obese patients with steatosis still had increased MRglu. There was no association between MRglu and chemotherapy history. We conclude that MRglu is increased in hepatic steatosis probably through insulin resistance, hyperinsulinaemia and up-regulation of hepatic hexokinase, irrespective of obesity.

A Computational Model of Hepatic Energy Metabolism: Understanding Zonated Damage and Steatosis in NAFLD

In non-alcoholic fatty liver disease (NAFLD), lipid build-up and the resulting damage is known to occur more severely in pericentral cells. Due to the complexity of studying individual regions of the sinusoid, the causes of this zone specificity and its implications on treatment are largely ignored. In this study, a computational model of liver glucose and lipid metabolism is presented which treats the sinusoid as the repeating unit of the liver rather than the single hepatocyte. This allows for inclusion of zonated enzyme expression by splitting the sinusoid into periportal to pericentral compartments. By simulating insulin resistance (IR) and high intake diets leading to the development of steatosis in the model, we identify key differences between periportal and pericentral cells accounting for higher susceptibility to pericentral steatosis. Secondly, variation between individuals is seen in both susceptibility to steatosis and in its development across the sinusoid. Around 25% of obese individuals do not show excess liver fat, whilst 16% of lean individuals develop NAFLD. Furthermore, whilst pericentral cells tend to show higher lipid levels, variation is seen in the predominant location of steatosis from pericentral to pan-sinusoidal or azonal. Sensitivity analysis was used to identify the processes which have the largest effect on both total hepatic triglyceride levels and on the sinusoidal location of steatosis. As is seen in vivo, steatosis occurs when simulating IR in the model, predominantly due to increased uptake, along with an increase in de novo lipogenesis. Additionally, concentrations of glucose intermediates including glycerol-3-phosphate increased when simulating IR due to inhibited glycogen synthesis. Several differences between zones contributed to a higher susceptibility to steatosis in pericentral cells in the model simulations. Firstly, the periportal zonation of both glycogen synthase and the oxidative phosphorylation enzymes meant that the build-up of glucose intermediates was less severe in the periportal hepatocyte compartments. Secondly, the periportal zonation of the enzymes mediating β-oxidation and oxidative phosphorylation resulted in excess fats being metabolised more rapidly in the periportal hepatocyte compartments. Finally, the pericentral expression of de novo lipogenesis contributed to pericentral steatosis when additionally simulating the increase in sterol-regulatory element binding protein 1c (SREBP-1c) seen in NAFLD patients in vivo. The hepatic triglyceride concentration was predicted to be most sensitive to inter-individual variation in the activity of enzymes which, either directly or indirectly, determine the rate of free fatty acid (FFA) oxidation. The concentration was most strongly dependent on the rate constants for β-oxidation and oxidative phosphorylation. It also showed moderate sensitivity to the rate constants for processes which alter the allosteric inhibition of β-oxidation by acetyl-CoA. The predominant sinusoidal location of steatosis meanwhile was most sensitive variations in the zonation of proteins mediating FFA uptake or triglyceride release as very low density lipoproteins (VLDL). Neither the total hepatic concentration nor the location of steatosis showed strong sensitivity to variations in the lipogenic rate constants.

Screening for Nonalcoholic Steatohepatitis in Individuals with Type 2 Diabetes: A Cost-Effectiveness Analysis

BACKGROUND AND AIM

Individuals with type 2 diabetes are at heightened risk for nonalcoholic fatty liver disease, which gives rise to nonalcoholic steatohepatitis (NASH) and cirrhosis. Yet, current guidelines do not recommend screening for NASH among these high-risk patients. Using a simulation model, we assessed the effectiveness and cost-effectiveness of screening diabetic patients for NASH.

METHODS

A Markov model was constructed to compare two management strategies for 50-year-olds with diabetes. In the No Screening strategy, patients do not undergo screening, although NASH may be diagnosed incidentally over their lifetime. In the NASH Screening strategy, all patients receive a one-time screening ultrasound. Individuals with fatty infiltration on ultrasound then have a liver biopsy, and those found to have NASH receive medical therapy, which decreases progression to cirrhosis. Endpoints evaluated included quality-adjusted life years (QALYs) gained, costs, and incremental cost-effectiveness ratios (ICERs).

RESULTS

Screening for NASH decreased the number of individuals who developed cirrhosis by 12.9 % and resulted in an 11.9 % decrease in liver-related deaths. However, screening resulted in 0.02 fewer QALYs, due to the disutility associated with treatment, and was therefore dominated by the No Screening strategy. When the model excluded this quality-of-life decrement, screening became cost-effective, at an ICER of $42,134 per QALY.

CONCLUSIONS

Screening for NASH may improve liver-related outcomes, but is not cost-effective at present, due to side effects of therapy. As better tolerated treatments for NASH become available, even with modest efficacy, screening for NASH will become cost-effective.

Artemisia capillaris formula inhibits hepatic steatosis via an miR‑122‑induced decrease in fatty acid synthase expression in vivo and in vitro

Non‑alcoholic fatty liver disease (NAFLD) is a widespread health concern, and there is currently insufficient understanding regarding its pathogenesis and treatment. The present study aimed to explore the effects of Artemisia capillaris formula (ACF) on high‑fat diet‑induced hepatic steatosis and fatty acid‑induced intracellular lipid accumulation, by micro (mi)RNA regulation. A total of 72 Sprague‑Dawley rats were divided into six groups (n=12/group). One group was designated as the control group and fed a normal diet, and the remaining five groups were allowed ad libitum access to a high‑fat diet for eight weeks, in order to establish an NAFLD rat model. The rats were subsequently administered polyene phosphatidylcholine (PP; 0.076 g/kg body weight/day), low dose of ACF (0.462 g/kg body weight/day), middle dose of ACF (0.924 g/kg body weight/day) or high dose of ACF (1.848 g/kg body weight/day) intragastrically for four weeks. HepG2 human hepatocellular carcinoma cells were treated with oleic acid and palm acid, followed by treatment with various concentrations of ACF. Serum alanine transaminase (ALT), aspartate aminotransferase (AST), triglycerides (TG), total cholesterol (TC), high‑density lipoprotein cholesterol (HDL‑C), low‑density lipoprotein cholesterol (LDL‑C), and steatotic HepG2 human liver carcinoma cell TC and TG levels were measured. ACF and PP treatments attenuated high‑fat diet‑induced hepatic steatosis and fatty acid‑induced intracellular lipid accumulation. A modified high‑fat diet significantly increased ALT, AST, TG, TC, LDL‑C levels and decreased HDL‑C levels. Treatment with ACF and PP abrogated the increase in liver enzymes and TG, TC and LDL‑C levels, but did not influence HDL‑C levels in a high‑fat diet induced rat model of steotosis. Steatotic HepG2 cells exhibited significantly increased levels of both TG and TC. Treatment with ACF significantly decreased TC and TG levels in vivo, and ACF and PP treatment decreased the expression levels of fatty acid synthase (FASN) and increased miR‑122 in vivo and in vitro. In conclusion, these results suggested that ACF may inhibit hepatic steatosis via miR‑122‑induced downregulation of FASN in vivo and in vitro.

Artemisia annua Leaf Extract Attenuates Hepatic Steatosis and Inflammation in High-Fat Diet-Fed Mice

Artemisia annua L. (AA) is a well-known source of the antimalarial drug artemisinin. AA also has an antibacterial and antioxidant activity. However, the effect of AA extract on hepatic steatosis induced by obesity is unclear. We investigated whether AA extract prevents obesity-induced insulin resistance and hepatic steatosis in high-fat diet (HFD)-fed mice. Mice were randomly divided into groups that received a normal chow diet or HFD with or without AA for 12 weeks. We found that AA extract reduced insulin resistance and hepatic steatosis in HFD-fed mice. Western blot analysis showed that HFD-induced expression of nuclear sterol regulatory element-binding protein 1 and carbohydrate-responsive element-binding protein in the livers was decreased by AA extract. In particular, dietary administration of AA extract decreased hepatic high-mobility group box 1 and cyclooxygenase-2 expression in HFD-fed mice. AA extract also attenuated HFD-induced collagen deposition and fibrosis-related transforming growth factor-β1 and connective tissue growth factor. These data indicate that dietary AA extract has beneficial effects on hepatic steatosis and inflammation in HFD-fed mice.

Diverse roles of the nucleic acid-binding protein KHSRP in cell differentiation and disease

The single-stranded nucleic acid-binding protein KHSRP (KH-type splicing regulatory protein) modulates RNA life and gene expression at various levels. KHSRP controls important cellular functions as different as proliferation, differentiation, metabolism, and response to infectious agents. We summarize and discuss experimental evidence providing a potential link between changes in KHSRP expression/function and human diseases including neuromuscular disorders, obesity, type II diabetes, and cancer.

Pregnane X receptor activation and silencing promote steatosis of human hepatic cells by distinct lipogenic mechanisms

In addition to its well-characterized role in the regulation of drug metabolism and transport by xenobiotics, pregnane X receptor (PXR) critically impacts on lipid homeostasis. In mice, both ligand-dependent activation and knockout of PXR were previously shown to promote hepatic steatosis. To elucidate the respective pathways in human liver, we generated clones of human hepatoma HepG2 cells exhibiting different PXR protein levels, and analyzed effects of PXR activation and knockdown on steatosis and expression of lipogenic genes. Ligand-dependent activation as well as knockdown of PXR resulted in increased steatosis in HepG2 cells. Activation of PXR induced the sterol regulatory element-binding protein (SREBP) 1-dependent lipogenic pathway via PXR-dependent induction of SREBP1a, which was confirmed in primary human hepatocytes. Inhibiting SREBP1 activity by blocking the cleavage-dependent maturation of SREBP1 protein impaired the induction of lipogenic SREBP1 target genes and triglyceride accumulation by PXR activation. On the other hand, PXR knockdown resulted in up-regulation of aldo-keto reductase (AKR) 1B10, which enhanced the acetyl-CoA carboxylase (ACC)-catalyzed reaction step of de novo lipogenesis. In a cohort of human liver samples histologically classified for non-alcoholic fatty liver disease, AKR1B10, SREBP1a and SREBP1 lipogenic target genes proved to be up-regulated in steatohepatitis, while PXR protein was reduced. In summary, our data suggest that activation and knockdown of PXR in human hepatic cells promote de novo lipogenesis and steatosis by induction of the SREBP1 pathway and AKR1B10-mediated increase of ACC activity, respectively, thus providing mechanistic explanations for a putative dual role of PXR in the pathogenesis of steatohepatitis.

Insulin resistance in the liver: deficiency or excess of insulin?

In insulin-resistant states (obesity, pre-diabetes, and type 2 diabetes), hepatic production of glucose and lipid synthesis are heightened in concert, implying that insulin deficiency and insulin excess coexists in this setting. The fact that insulin may be inadequate or excessive at any one point in differing organs and tissues has many biologic ramifications. In this context the concept of metabolic compartmentalization in the liver is offered herein as one perspective of this paradox. In particular, we focus on the hypothesis that insulin resistance accentuates differences in periportal and perivenous hepatocytes, namely periportal glucose production and perivenous lipid synthesis. Subsequently, excessive production of glucose and accumulation of lipids could be expected in the livers of patients with obesity and insulin resistance. Overall, in this review, we provide our integrative perspective regarding how excessive production of glucose in periportal hepatocytes and accumulation of lipids in perivenous hepatocytes interact in insulin resistant states.

Antioxidant and Anti-Inflammatory Activities of Kenyan Leafy Green Vegetables, Wild Fruits, and Medicinal Plants with Potential Relevance for Kwashiorkor

Background. Inflammation, together with related oxidative stress, is linked with the etiology of kwashiorkor, a form of severe acute malnutrition in children. A diet rich in anti-inflammatory and antioxidant phytochemicals may offer potential for the prevention and treatment of kwashiorkor. We selected and assayed five leafy green vegetables, two wild fruits, and six medicinal plants from Kenya for their antioxidant and anti-inflammatory properties. Consensus regarding medicinal plant use was established from ethnobotanical data. Methods. Antioxidant activity and phenolic content were determined using the oxygen radical absorbance capacity (ORAC) assay and Folin-Ciocalteu procedure, respectively. Anti-inflammatory activity was assessed in vitro targeting the inflammatory mediator tumour necrosis factor-alpha (TNF-α). Results. Mangifera indica (leaves used medicinally) showed the greatest antioxidant activity (5940 ± 632 µM TE/µg) and total phenolic content (337 ± 3 mg GAE/g) but Amaranthus dubius (leafy vegetable) showed the greatest inhibition of TNF-α (IC₅₀ = 9 ± 1 μg/mL), followed by Ocimum americanum (medicinal plant) (IC₅₀ = 16 ± 1 μg/mL). Informant consensus was significantly correlated with anti-inflammatory effects among active medicinal plants (r² = 0.7639,  P = 0.0228). Conclusions. Several plant species commonly consumed by Kenyan children possess activity profiles relevant to the prevention and treatment of kwashiorkor and warrant further investigation.

RGC-32 Deficiency Protects against Hepatic Steatosis by Reducing Lipogenesis

Hepatic steatosis is associated with insulin resistance and metabolic syndrome because of increased hepatic triglyceride content. We have reported previously that deficiency of response gene to complement 32 (RGC-32) prevents high-fat diet (HFD)-induced obesity and insulin resistance in mice. This study was conducted to determine the role of RGC-32 in the regulation of hepatic steatosis. We observed that hepatic RGC-32 was induced dramatically by both HFD challenge and ethanol administration. RGC-32 knockout (RGC32(-/-)) mice were resistant to HFD- and ethanol-induced hepatic steatosis. The hepatic triglyceride content of RGC32(-/-) mice was decreased significantly compared with WT controls even under normal chow conditions. Moreover, RGC-32 deficiency decreased the expression of lipogenesis-related genes, sterol regulatory element binding protein 1c (SREBP-1c), fatty acid synthase, and stearoyl-CoA desaturase 1 (SCD1). RGC-32 deficiency also decreased SCD1 activity, as indicated by decreased desaturase indices of the liver and serum. Mechanistically, insulin and ethanol induced RGC-32 expression through the NF-κB signaling pathway, which, in turn, increased SCD1 expression in a SREBP-1c-dependent manner. RGC-32 also promoted SREBP-1c expression through activating liver X receptor. These results demonstrate that RGC-32 contributes to the development of hepatic steatosis by facilitating de novo lipogenesis through activating liver X receptor, leading to the induction of SREBP-1c and its target genes. Therefore, RGC-32 may be a potential novel drug target for the treatment of hepatic steatosis and its related diseases.

NADPH Oxidase-Derived Peroxynitrite Drives Inflammation in Mice and Human Nonalcoholic Steatohepatitis via TLR4-Lipid Raft Recruitment

The molecular events that link NADPH oxidase activation and the induction of Toll-like receptor (TLR)-4 recruitment into hepatic lipid rafts in nonalcoholic steatohepatitis (NASH) are unclear. We hypothesized that in liver, NADPH oxidase activation is key in TLR4 recruitment into lipid rafts, which in turn up-regulates NF-κB translocation to the nucleus and subsequent DNA binding, leading to NASH progression. Results from confocal microscopy showed that liver from murine and human NASH had NADPH oxidase activation, which led to the formation of highly reactive peroxynitrite, as shown by 3-nitrotyrosine formation in diseased liver. Expression and recruitment of TLR4 into the lipid rafts were significantly greater in rodent and human NASH. The described phenomenon was NADPH oxidase, p47phox, and peroxynitrite dependent, as liver from p47phox-deficient mice and from mice treated with a peroxynitrite decomposition catalyst [iron(III) tetrakis(p-sulfonatophenyl)porphyrin] or a peroxynitrite scavenger (phenylboronic acid) had markedly less Tlr4 recruitment into lipid rafts. Mechanistically, peroxynitrite-induced TLR4 recruitment was linked to increased IL-1β, sinusoidal injury, and Kupffer cell activation while blocking peroxynitrite-attenuated NASH symptoms. The results strongly suggest that NADPH oxidase-mediated peroxynitrite drove TLR4 recruitment into hepatic lipid rafts and inflammation, whereas the in vivo use of the peroxynitrite scavenger phenylboronic acid, a novel synthetic molecule having high reactivity with peroxynitrite, attenuates inflammatory pathogenesis in NASH.

Obstructive sleep apnea is associated with liver disease: a population-based cohort study

BACKGROUND

The association between obstructive sleep apnea (OSA) and the risk of liver disease is unclear. Moreover, population-based studies on the risk of liver disease among people with OSA have not yet been conducted. This study aimed to investigate the risk of subsequent development of liver disease among people with OSA.

METHODS

Using Taiwan National Health Insurance claims data, this study collected subjects from a cohort of 17,374 people with OSA who were diagnosed between 2000 and 2008. A control group of 69,496 people was selected from the same database and matched by age, gender, urbanization, income, and date of initial admission. All subjects were followed up until 2010. Liver disease incidence and risk were calculated.

RESULTS

The overall risk of liver disease among people with OSA was significantly higher than in the control group (aHR = 5.52, p <0.001). Non-alcoholic fatty liver disease, cirrhosis, and hepatitis C had significant aHRs of 5.29, 7.50, and 7.19 (all at p <0.001), respectively. In contrast, hepatitis B had the smallest aHR of 3.71.

CONCLUSIONS

The risk of liver disease was more than five times higher among people with OSA compared with the control group; this was particularly for cirrhosis and hepatitis C. Liver disease is thus a very important health issue among people with OSA.

Ameliorative potential of omega 3 fatty acids and HMG-CoA reductase inhibitors on experimentally-induced non-alcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH) has a relation to obesity. It may lead to hepatocellular carcinoma. To date, the therapeutic options are limited due to complex pathogenesis. This study aimed to investigate the effect of atorvastatin and omega 3 fatty acids on experimentally-induced NASH. Sixty male albino rats were divided into 6 equal groups; control group, high fat emulsion/sucrose (HFE/S) diet, HFE/S+carboxymethyl cellulose, HFE/S +Atorvastatin, HFE/S+Fish oil and HFE/S+Atorvastatin+Fish oil. Serum alanine aminotransferase, total cholesterol (TC), triglycerides (TG), high density lipoproteins, insulin, glucose, C-reactive protein and quantitative insulin sensitivity check index were measured. Also, hepatic TC, TG, malondialdehyde, tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6) and transforming growth factor beta 1 (TGF-β1) were determined. Liver sections were examined histopathologically. Atorvastatin improved lipid profile, inflammation and oxidative stress but did not improve insulin resistance, hepatic TGF-β1 or body weight while fish oil improved lipid profile, decreased inflammation and oxidative stress, improved insulin resistance, hepatic TGF-β1 and body weight compared to HFE/S group. Atorvastatin/fish oil combination produced significant improvement in the lipid profile, inflammation, oxidative stress, insulin resistance, hepatic TGF-β1 and body weight compared to the use of each of these drugs alone. This might be attributed to the effect of fish oil on the lipid profile, inflammatory cytokines, insulin resistance and TGF-β1 which potentiates the effect of atorvastatin on NASH.