The Natural Course of Non-Alcoholic Fatty Liver Disease

Components of metabolic syndrome increase the risk of mortality in nonalcoholic fatty liver disease (NAFLD)

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the United States. Metabolic syndrome (MS) components are highly prevalent in NAFLD. Our aim is to assess the relationship of NAFLD and MS with long-term outcome of mortality.The Third National Health and Nutrition Examination Survey (NHANES) was utilized. NAFLD was diagnosed by ultrasound in the presence of hepatic steatosis and no other causes of chronic liver disease. History of MS and its components were obtained from self-reported NHANES questionnaires. Mortality was obtained from Mortality-Linkage File, through December 31, 2011. Chi-square test was used for categorical variables and Cox proportional models estimated hazard ratios with 95% confidence interval.NAFLD cohort (n = 3613) had a median age of 43 years, 73% white, and 50% male. NAFLD group with at least one MS condition was significantly older, had higher body mass index, more likely to have insulin resistance, and heart disease compared to NAFLD group without MS. Over 19-years of follow-up, 1039 people died. Compared to NAFLD patients without MS, presence of one MS component increased the risk of mortality at 8-year (2.6% vs 4.7%) and 16-year (6% vs 11.9%) (P < .001). After adjusting for socio-demographic factors, NAFLD with all MS components was associated with overall, cardiac and liver-mortality. Increased number of MS components was associated with lower survival (P < .0001).Patients with NAFLD and MS have higher mortality risk compared to NAFLD patients without MS. These NAFLD patients should be prioritized for the development of treatment regimens.

Non-alcoholic fatty liver disease: controlling an emerging epidemic, challenges, and future directions

Non-alcoholic fatty liver disease (NAFLD) affects over 30% of the United States population and is projected to become a leading cause of chronic liver disease by 2020. As a result, the economic and societal burden of NAFLD is far-reaching. The cost of managing NAFLD complications has an estimated 10 year economic burden of $908 billion. This review provides an overview of current knowledge on NAFLD, with emphasis on identifying gaps in its diagnosis and management, and proposes future directions to address these limitations. Despite the increasing prevalence of NAFLD, there is limited knowledge and practice regarding its natural history, staging, diagnosis, and management. Though a challenging task, opportunities for bridging these gaps should focus on the development of noninvasive biomarkers, the elucidation of biological pathways, the creation of up-to-date screening guidelines, and the organization of clinical trials of longer duration to determine clinical endpoints and assess the safety of new treatment options.

Chymase Inhibitor as a Novel Therapeutic Agent for Non-alcoholic Steatohepatitis

Non-alcoholic steatohepatitis (NASH) is characterized by inflammation and fibrosis, in addition to steatosis, of the liver, but no therapeutic agents have yet been established. The mast cell protease chymase can generate angiotensin II, matrix metalloproteinase-9 and transforming growth factor-β, all of which are associated with liver inflammation or fibrosis. In animal models of NASH, augmented chymase has been observed in the liver. In histological analysis, chymase inhibitor prevented hepatic steatosis, inflammation, and fibrosis. Chymase inhibitor also attenuated the augmentation of angiotensin II, matrix metalloproteinase-9, and transforming growth factor-β observed in the liver of NASH. Oxidative stress, inflammatory markers, and collagen were attenuated by chymase inhibition. Moreover, chymase inhibitor showed a mitigating effect on established NASH, and survival rates were significantly increased by treatment with chymase inhibitor. In this review, we propose that chymase inhibitor has potential as a novel therapy for NASH.

Therapeutic application of GPR119 ligands in metabolic disorders

GPR119 belongs to the G protein-coupled receptor family and exhibits dual modes of action upon ligand-dependent activation: pancreatic secretion of insulin in a glucose-dependent manner and intestinal secretion of incretins. Hence, GPR119 has emerged as a promising target for treating type 2 diabetes mellitus without causing hypoglycaemia. However, despite continuous efforts by many major pharmaceutical companies, no synthetic GPR119 ligand has been approved as a new class of anti-diabetic agents thus far, nor has any passed beyond phase II clinical studies. Herein, we summarize recent advances in research concerning the physiological/pharmacological effects of GPR119 and its synthetic ligands on the regulation of energy metabolism, and we speculate on future applications of GPR119 ligands for the treatment of metabolic diseases, focusing on non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease phenotypes in patients with inflammatory bowel disease

Non-alcoholic fatty liver disease (NAFLD) can be detected in up to 33.6% of inflammatory bowel disease (IBD) patients, often in absence of metabolic risk factors. Nevertheless, most of previous studies on such issue were conducted within the IBD population only. The primary aim of this study was to compare clinical and metabolic features of NAFLD in patients with and without IBD (w/o IBD) and to identify specific NAFLD phenotypes within the IBD population. Among 223 NAFLD patients, 78 patients with IBD were younger compared to 145 without (w/o) IBD, were less likely to have altered liver enzymes, had lower mean body weight, smaller waist circumference and lower body mass index (BMI); at the same time, MetS was more prevalent among patients w/o IBD (56.6 vs. 23.1%, p < 0.001). Within IBD population, patients with severe IBD showed more often severe steatosis (S3) at ultrasound (US) (32.1 vs. 16.6%, p = 0.01), compared to mild-to-moderate disease. Independent risk factors for S3 US steatosis in IBD patients at the multivariate logistic regression analysis were: more than 1 IBD relapse per year during disease history (OR 17.3, 95% CI 3.6-84), surgery for IBD (OR 15.1, 95% CI 3.1-73.7) and more extensive intestinal involvement (OR 19.4, 95% CI 3.4-110.9); the ongoing anti-Tumor Necrosis Factor alpha (antiTNFα) therapy was the only independent factor which protect toward the presence of altered liver enzymes (OR 0.15, 95% CI 0-0.8, p = 0.02). In conclusion, NAFLD in IBD patients is different from that in patients w/o IBD, who seem to develop different NAFLD phenotypes according to intestinal disease clinical course. More severe IBD seem to predict the presence of more severe steatosis. Therapy with antiTNFα antibodies could prevent alteration of liver enzymes in such population.

Hypothermic Machine Preservation of the Liver: State of the Art

PURPOSE OF REVIEW

In this review, we highlight which livers may benefit from additional treatment before implantation and describe the concept of hypothermic machine liver perfusion. Furthermore, we explain why cold oxygenated perfusion concepts could potentially lead to a breakthrough in this challenging field of transplantation. Accordingly, we summarize recent clinical applications of different hypothermic perfusion approaches.

RECENT FINDINGS

The impact of end-ischemic, hypothermic liver perfusion in liver transplantation is currently assessed by two multicenter, randomized controlled trials. Recently, new applications of hypothermic perfusion showed promising results and recipients were protected from severe intrahepatic biliary complications, despite the use of very extended criteria grafts including donation after circulatory death livers.

SUMMARY

Hypothermic machine liver perfusion is beneficial for high-risk livers and protects recipients from most feared complications. Importantly, such easy approach is currently implemented in several European centers and new markers obtained from perfusate may improve the prediction of liver function in the future.

circRNA_0046366 inhibits hepatocellular steatosis by normalization of PPAR signaling

AIM

To investigate micro (mi)R-34a-antagonizing circular (circ)RNA that underlies hepatocellular steatosis.

METHODS

The effect of circRNA on miR-34a was recognized by the miRNA response element (MRE), and validated by the dual-luciferase reporter assay. Its association with hepatocellular steatosis was investigated in HepG2-based hepatocellular steatosis induced by free fatty acids (FFAs; 2:1 oleate:palmitate) stimulation. After normalization of the steatosis-related circRNA by expression vector, analysis of miR-34a activity, peroxisome proliferator-activated receptor (PPAR)α level, and expression of downstream genes were carried out so as to reveal its impact on the miR-34a/PPARα regulatory system. Both triglyceride (TG) assessment and cytopathological manifestations uncovered the role of circRNA in miR-34a-dependent hepatosteatogenesis.

RESULTS

Bioinformatic and functional analysis verified circRNA_0046366 to antagonize the activity of miR-34a via MRE-based complementation. In contrast to its lowered level during FFA-induced hepatocellular steatosis, circRNA_0046366 up-regulation abolished the miR-34a-dependent inhibition of PPARα that played a critical role in metabolic signaling pathways. PPARα restoration exerted transcriptional improvement to multiple genes responsible for lipid metabolism. TG-specific lipolytic genes [carnitine palmitoyltransferase 1A (CPT1A) and solute-carrier family 27A (SLC27A)] among these showed significant increase in their expression levels. The circRNA_0046366-related rebalancing of lipid homeostasis led to dramatic reduction of TG content, and resulted in the ameliorated phenotype of hepatocellular steatosis.

CONCLUSION

Dysregulation of circRNA_0046366/miR-34a/PPARα signaling may be a novel epigenetic mechanism underlying hepatocellular steatosis. circRNA_0046366 serves as a potential target for the treatment of hepatic steatosis.

Neonatal overfeeding in mice aggravates the development of methionine and choline-deficient diet-induced steatohepatitis in adulthood

Overfeeding in early life is associated with obesity and insulin resistance in adulthood. In the present study, a well-characterized mouse model was used to investigate whether neonatal overfeeding increases susceptibility to the development of non-alcoholic steatohepatitis (NASH) following feeding with a methionine and choline- deficient (MCD) diet. Neonatal overfeeding was induced by adjusting litters to 3 pups per dam (small litter size, SL) in contrast to 10 pups per dam as control (normal litter size, NL). At 11 weeks of age, mice were fed with standard (S) or a methionine and choline-deficient (MCD) diet for 4 weeks. Glucose tolerance tests, tissue staining with haematoxylin and eosin, oil-red O and immunohistochemistry for F4/80, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting were performed. Compared with NL mice, SL mice exhibited higher body weight gain from 2 weeks of age throughout adulthood, and more profound glucose intolerance as adults. Sterol regulatory element-binding protein 1c and fatty acid synthase mRNA expression levels in liver were upregulated in SL mice at 3 weeks of age. MCD diet induced typical NASH, especially in SL-MCD mice, evidenced by marked fat accumulation, macrovescular steatosis, ballooned hepatocytes, inflammatory cells infiltration and tumour necrosis factor-α mRNA upregulation in the liver, as well as increased alanine aminotransferase and aspartate aminotransferase levels in the serum. There were no significant differences in liver fibrosis in all groups. Overfeeding during early life exhibited effect with administration of MCD diet in inducing adverse effects on the metabolic function and in promoting the progression of NASH in mice, possibly mediated through dysregulated lipid metabolism in hepatocytes and aggravated hepatic inflammation.

The Antidiabetic Drug Lobeglitazone Protects Mice From Lipogenesis-Induced Liver Injury via Mechanistic Target of Rapamycin Complex 1 Inhibition

Non-alcoholic fatty liver disease (NAFLD) is a metabolic disorder closely linked with type II diabetes (T2D). The progression of NAFLD is associated with the induction of lipogenesis through hyperactivation of the mechanistic target of rapamycin complex 1 (mTORC1) pathway. An increase in lipogenesis induces endoplasmic reticulum (ER) stress and accelerates oxidative liver injury in the pathogenesis of NAFLD. Lobeglitazone, one of thiazolidinediones (TZDs), is used as an antidiabetic drug to lower serum glucose level through an increase in insulin sensitivity. It is known to improve pathological symptoms in animals and humans with NAFLD. However, the underlying molecular mechanism of the protective effects of lobeglitazone against NAFLD has not been elucidated. Here, we show that under the physiological condition of acute lipogenesis, lobeglitazone inhibits hepatic lipid synthesis, the subsequent ER stress, and ω-oxidation of fatty acids by inhibiting the mTORC1 pathway. As a result, lobeglitazone protected mice from lipogenesis-induced oxidative liver injury. Taken together, lobeglitazone might be a suitable drug for the treatment of patients with diabetes and NAFLD.

Trend over time in hepatic fibrosis score in a cohort of type 2 diabetes patients

AIMS

The prevalence and progression of hepatic fibrosis and its correlated factors in type 2 diabetes (T2DM) are poorly known. We aimed to define the percentage of T2DM patients who progress to fibrosis and the factors associated with disease progression.

METHODS

Data from the electronic health records of 1527 patients with diagnosed T2DM and nonalcoholic fatty liver disease (NAFLD), as diagnosed by the Fatty Liver Index, were extracted from the AMD Annals database, which collects data from the Italian network of diabetes clinics. For the main analysis, we evaluated variables associated with Fibrosis 4 [FIB-4] score at baseline and at 3-year follow-up to determine their role in predicting FIB-4 at 3 years and the risk of hepatic fibrosis in T2DM.

RESULTS

High-risk of advanced fibrosis was detected in 13.1% of patients at baseline and in 18.1% at 3 years, LDL cholesterol, and body-mass index, correlated negatively with baseline FIB-4 scores, whereas gamma glutamil transerasi correlated positively . The FIB-4 score at 3 years was associated with lower values of baseline renal function, LDL, and BMI; however, the baseline FIB-4 score was the strongest predictor for the FIB-4 score at 3 years.

CONCLUSIONS

The prevalence of and progression to hepatic fibrosis within 3 years in patients with T2DM is not negligible. Patients with a higher likelihood of liver scarring differ from those with hepatic steatosis. Differently from NAFLD, the FIB-4 score is inversely correlated with insulin resistance and appears to increase independent of classic metabolic factors.

Non-alcoholic Fatty Liver Disease: A Clinical Update

Non-alcoholic fatty liver disease (NAFLD) is currently the most common chronic liver disease in developed countries because of the obesity epidemic. The disease increases liver-related morbidity and mortality, and often increases the risk for other comorbidities, such as type 2 diabetes and cardiovascular disease. Insulin resistance related to metabolic syndrome is the main pathogenic trigger that, in association with adverse genetic, humoral, hormonal and lifestyle factors, precipitates development of NAFLD. Biochemical markers and radiological imaging, along with liver biopsy in selected cases, help in diagnosis and prognostication. Intense lifestyle changes aiming at weight loss are the main therapeutic intervention to manage cases. Insulin sensitizers, antioxidants, lipid lowering agents, incretin-based drugs, weight loss medications, bariatric surgery and liver transplantation may be necessary for management in some cases along with lifestyle measures. This review summarizes the latest evidence on the epidemiology, natural history, pathogenesis, diagnosis and management of NAFLD.

Quantitative assessment of liver fibrosis reveals a nonlinear association with fibrosis stage in nonalcoholic fatty liver disease

Accurate staging of liver fibrosis is crucial to guide therapeutic decisions for patients with nonalcoholic fatty liver disease (NAFLD). Digital image analysis has emerged as a promising tool for quantitative assessment of fibrosis in chronic liver diseases. We sought to determine the relationship of histologic fibrosis stage with fiber amounts quantified in liver biopsy specimens for the better understanding of NAFLD progression. We measured area ratios of collagen and elastin fibers in Elastica van Gieson-stained biopsy tissues from 289 patients with NAFLD from four hospitals using an automated computational method and examined their correlations with Brunt's fibrosis stage. As a secondary analysis, we performed multivariable logistic regression analysis to assess the associations of the combined area ratios of collagen and elastin with noninvasive fibrosis markers. The combined fiber area ratios correlated strongly with Brunt's stage (Spearman correlation coefficient, 0.78; P < 0.0001), but this relationship was nonlinear (P = 0.007) with striking differences between stage 4 (median area ratios, 12.3%) and stages 0-3 (2.1%, 2.8%, 4.3%, and 4.8%, respectively). Elastin accumulation was common in areas of thick bridging fibrosis and thickened venous walls but not in areas of perisinusoidal fibrosis. The highest tertile of the combined fiber area ratios was associated with the fibrosis-4 index and serum type IV collagen 7s domain (7s collagen) levels, whereas the upper two tertiles of the fiber amounts significantly associated with body mass index, aspartate aminotransferase, and 7s collagen in the multivariable analysis. Conclusion: Quantitative fibrosis assessment reveals a nonlinear relationship between fibrosis stage and fiber amount, with a marked difference between stage 4 and stage 3 and much smaller differences among stages 0-3, suggesting a heterogeneity in disease severity within NAFLD-related cirrhosis. (Hepatology Communications 2018;2:58-68).

Altered pharmacokinetics of rosiglitazone in a mouse model of non-alcoholic fatty liver disease

BACKGROUND

Severe forms of non-alcoholic fatty liver disease (NAFLD) adversely affect the liver physiology and hence the pharmacokinetics of drugs. Here, we investigated the effect of NAFLD on the pharmacokinetics of rosiglitazone, an insulin sensitizer used in the treatment of type 2 diabetes.

METHODS

Male C57BL/6 mice were divided into two groups. The first group (n=14) was fed with normal chow feed and the second group (n=14) was fed with 60% high-fat diet (HFD) and 40% high fructose liquid (HFL) for 60 days to induce NAFLD. The development of NAFLD was confirmed by histopathology, liver triglyceride levels and biochemical estimations, and used for pharmacokinetic investigations. Rosiglitazone was administered orally at 30 mg/kg dose. At predetermined time points, blood was collected and rosiglitazone concentrations were determined using LC/MS/MS. Plasma concentrations were subjected to non-compartmental analysis using Phoenix WinNonlin (6.3), and the area under the plasma concentration-time curve (AUC) was calculated by the linear-up log-down method.

RESULTS

HFD and HFL diet successfully induced NAFLD in mice. Rosiglitazone pharmacokinetics in NAFLD animals were altered significantly as compared to healthy mice. Rosiglitazone exposure increased significantly in NAFLD mice (2.5-fold higher AUC than healthy mice). The rosiglitazone oral clearance was significantly lower and the mean plasma half-life was significantly longer in NAFLD mice as compared to healthy mice.

CONCLUSIONS

The NAFLD mouse model showed profound effects on rosiglitazone pharmacokinetics. The magnitude of change in rosiglitazone pharmacokinetics is similar to that observed in humans with moderate to severe liver disease. The present animal model can be utilized to study the NAFLD-induced changes in the pharmacokinetics of different drugs.

Microcirculatory disturbances and cellular changes during progression of hepatic steatosis to liver tumors

Non-alcoholic fatty liver disease is closely associated with metabolic syndrome and comprises a pathological spectrum of liver disease ranging from steatosis to steatohepatitis and can progress to fibrosis/cirrhosis and hepatocellular carcinoma. In 2013, a mouse model was described that mimics non-alcoholic fatty liver disease progression from steatohepatitis to tumors in a short time span and with high incidence. As microcirculatory disturbances play a crucial role in liver disease, the suitability of the steatosis-inflammation-tumor model for microcirculatory studies was assessed. Herein, we present a comprehensive view on morphological, microvascular, cellular, and functional aspects of non-alcoholic fatty liver disease progression in the steatosis-inflammation-tumor model using intravital microscopy, biochemical, and histological techniques. Mice develop steatohepatitis, mild fibrosis, and liver tumors at ages of 6, 12, and 20 weeks, respectively. Non-alcoholic fatty liver disease progression was accompanied by several general aspects of disease severity like increasing liver/body weight index, non-alcoholic fatty liver disease activity score, and hepatocellular apoptosis. Intravital microscopic analysis revealed significant changes in hepatic microcirculation with increasing structural alterations, elevated leukocyte adherence, and impaired nutritive perfusion. Non-alcoholic fatty liver disease was further characterized by a lower sinusoidal density with a striking rise at 20 weeks. The characteristic microcirculatory changes make the model a convenient tool for analysis of microcirculation during progression from steatosis to liver tumor. Impact statement Significant alterations of microcirculation contribute to progression of NAFLD, a chronic liver disease with increasing medical and socio-economic impact. Characterization of microcirculation in a NAFLD model reflecting all relevant stages of disease progression was still missing. Thus, we evaluated microcirculatory and cellular changes in a steatosis-inflammation-tumor model using in vivo microscopy. Analyses revealed increasing structural alterations, elevated leukocyte-endothelial interaction, and impaired nutritive perfusion. Thus, this model is suitable for further studies investigating therapeutic approaches targeting these progressive microcirculatory disturbances.

Nation-wide trends in non-alcoholic steatohepatitis (NASH) in patients with and without diabetes between 2004-05 and 2014-15 in England

AIMS

There are no national studies evaluating the epidemiology of non-alcoholic steatohepatitis (NASH) in England. NASH is becoming an increasingly important health issue given the inexorable rise in obesity and diabetes. We evaluated the rates of NASH in people with and without diabetes from 2004-2005 to 2014-2015.

METHODS

We identified cases of biopsy-proven NASH in people with and without diabetes in England over an eleven-year period using Hospital Episode Statistics. We estimated incidence rates for each year. Negative binomial regression models were fitted to test trends.

RESULTS

Over the study period, people without diabetes recorded a 3% reduction in admission rates per year (incidence rate ratio (IRR) (95% CI) 0.97 (0.96-0.98), p<0.001), whilst there was an increase in admission rates in people with diabetes (IRR (95% CI) 1.01 (1.00-1.02), p=0.04). In people with diabetes, this upward trend was driven by people over 65years (IRR (95% CI) 1.03 (1.02-1.04), p<0.001) and men (IRR (95% CI) 1.01 (1.0-1.02), p=0.03). Inpatient mortality declined for people with diabetes by 2% per year after adjusting for age, sex and year (IRR (95% CI) 0.98 (0.95-0.99), p=0.03). The 2% decline per year in inpatient mortality for people without diabetes did not achieve statistical significance after adjustment (IRR (95% CI) 0.98 (0.95-1.01), p=0.175).

CONCLUSIONS

There was a decline in NASH-related hospital admissions amongst people without diabetes over eleven years, whilst rates increased in people with diabetes. These observations highlight the increasing burden of NASH.

Nonalcoholic fatty liver disease: Evolving paradigms

In the last years new evidence has accumulated on nonalcoholic fatty liver disease (NAFLD) challenging the paradigms that had been holding the scene over the previous 30 years. NAFLD has such an epidemic prevalence as to make it impossible to screen general population looking for NAFLD cases. Conversely, focusing on those cohorts of individuals exposed to the highest risk of NAFLD could be a more rational approach. NAFLD, which can be diagnosed with either non-invasive strategies or through liver biopsy, is a pathogenically complex and clinically heterogeneous disease. The existence of metabolic as opposed to genetic-associated disease, notably including ”lean NAFLD” has recently been recognized. Moreover, NAFLD is a systemic condition, featuring metabolic, cardiovascular and (hepatic/extra-hepatic) cancer risk. Among the clinico-laboratory features of NAFLD we discuss hyperuricemia, insulin resistance, atherosclerosis, gallstones, psoriasis and selected endocrine derangements. NAFLD is a precursor of type 2 diabetes (T2D) and metabolic syndrome and progressive liver disease develops in T2D patients in whom the course of disease is worsened by NAFLD. Finally, lifestyle changes and drug treatment options to be implemented in the individual patient are also critically discussed. In conclusion, this review emphasizes the new concepts on clinical and pathogenic heterogeneity of NAFLD, a systemic disorder with a multifactorial pathogenesis and protean clinical manifestations. It is highly prevalent in certain cohorts of individuals who are thus potentially amenable to selective screening strategies, intensive follow-up schedules for early identification of liver-related and extrahepatic complications and in whom earlier and more aggressive treatment schedules should be carried out whenever possible.

Impact of bariatric surgery on outcomes of patients with nonalcoholic fatty liver disease: a nationwide inpatient sample analysis, 2004-2012

BACKGROUND

Bariatric surgery in eligible morbidly obese individuals may improve liver steatosis, inflammation, and fibrosis; however, population-based data on the clinical benefits of bariatric surgery in patients with nonalcoholic fatty liver disease (NAFLD) are lacking.

OBJECTIVES

To assess the relationship between bariatric surgery and clinical outcomes in hospitalized patients with NAFLD.

SETTING

United States inpatient care database.

METHODS

The Nationwide Inpatient Sample database was queried from 2004 to 2012 with co-diagnoses of NAFLD and morbid obesity. Hospitalizations with a history of prior bariatric surgery (Roux-en-Y gastric bypass, gastric band, and sleeve gastrectomy) were also identified. The primary outcome was in-hospital mortality. Secondary outcomes included cirrhosis, myocardial infarction, stroke, and renal failure. Poisson regression was used to derive adjusted incidence risk ratios for clinical outcomes in patients with prior bariatric surgery compared with those without bariatric surgery.

RESULTS

Among 45,462 patients with a discharge diagnosis of NAFLD and morbid obesity, 18,618 patients (41.0%) had prior bariatric surgery. There was a downward trend in bariatric surgery procedures (percent annual change of -5.94% from 2004 to 2012). In a multivariable analysis, prior bariatric surgery was associated with decreased inpatient mortality compared with no bariatric surgery (incidence risk ratios = .08; 95% confidence interval, .03-.20, P<.001). Prior bariatric surgery was also associated with decreased incidence risk ratios for cirrhosis, myocardial infarction, stroke, and renal failure (all P<.001).

CONCLUSIONS

Prior bariatric surgery is associated with decreased in-hospital morbidity and mortality in morbidly obese NAFLD patients. Despite this, the proportion of NAFLD patients with bariatric surgery has declined from 2004 to 2012.

NAFLD: Is There Anything New under the Sun?

Nonalcoholic fatty liver disease (NAFLD) is an "umbrella" definition that encompasses a spectrum of histological liver changes ranging from simple steatosis to nonalcoholic steatohepatitis (NASH) with/without fibrosis, "cryptogenic" cirrhosis, and hepatocellular carcinoma (HCC), occurring in a dysmetabolic milieu, though in the absence of excessive alcohol consumption and other competing etiologies of chronic liver disease [1].[...].

Therapeutic opportunities for alcoholic steatohepatitis and nonalcoholic steatohepatitis: exploiting similarities and differences in pathogenesis

Alcoholic steatohepatitis (ASH) and nonalcoholic steatohepatitis (NASH) are among the most frequent causes of chronic liver disease in the United States. Although the two entities are triggered by different etiologies - chronic alcohol consumption (ASH) and obesity-associated lipotoxicity (NASH) - they share overlapping histological and clinical features owing to common pathogenic mechanisms. These pathogenic processes include altered hepatocyte lipid metabolism, organelle dysfunction (i.e., ER stress), hepatocyte apoptosis, innate immune system activation, and hepatic stellate cell activation. Nonetheless, there are several disease-specific molecular signaling pathways, such as differential pathway activation downstream of TLR4 (MyD88-dependence in NASH versus MyD88-independence in ASH), inflammasome activation and IL-1β signaling in ASH, insulin resistance and lipotoxicity in NASH, and dysregulation of different microRNAs, which clearly highlight that ASH and NASH are two distinct biological entities. Both pathogenic similarities and differences have therapeutic implications. In this Review, we discuss these pathogenic mechanisms and their therapeutic implications for each disease, focusing on both shared and distinct targets.

Is there a J-shaped relationship between the fatty liver index and risk of microalbuminuria in the general population?

BACKGROUND

We investigated whether the fatty liver index (FLI), as a clinical indicator of hepatic fat accumulation based on body mass index, gamma-glutamyl-transferase, triglycerides, and waist circumference, has an association with microalbuminuria.

METHODS

We analyzed anthropometric and biochemical data from a nation-wide, population-based, cross-sectional study. A total of 1605 participants included were healthy native Korean 40years or older and divided into quintiles according to their log-FLI and sex. Microalbuminuria was defined as urine albumin/creatinine ratio (UACR) between 30 and 300mg/g.

RESULTS

Participants in higher quintiles of log-FLI were more obese and hypertensive and had greater glycemic exposure, poorer lipid profiles, and greater increases in log-UACR compared with lower quintiles. Linear regression analysis demonstrated that log-FLI was associated with systolic and diastolic blood pressure, body mass index, waist circumference, fasting plasma glucose, glycated hemoglobin, and log-UACR. In logistic regression adjusted for age, sex, body mass index, waist circumference, and fasting plasma glucose, the OR of microalbuminuria was elevated in quintile 1 (adjusted OR=2.161, 95% CI=0.453-10.31) and quintile 5 (adjusted OR=6.387, 95% CI=1.317-51.58), when compared to quintile 2.

CONCLUSIONS

There appears to be a J-shaped association between FLI and UACR in healthy general population.

Nonalcoholic fatty liver disease associated with metabolic syndrome: Influence of liver fibrosis stages on characteristics of very low-density lipoproteins

BACKGROUND

We evaluated possible changes in VLDLcharacteristics, and metabolic related factors, in MetS-associated NAFLD and accompanying liver fibrosis.

METHODS

We studied 36 MetS patients with biopsy-proven NAFLD (MetS+NAFLD) and 24 MetS without ultrasound NAFLD evidence. Further, MetS+NAFLD was sub-divided according to fibrosis stage into, non-to-moderate (F0-F2, n=27) and severe (F3-F4, n=9) fibrosis. We measured: lipid profile, VLDL composition and size (size exclusion-HPLC), CETP and lipoprotein lipase (LPL) activities and adiponectin. Additionally, in MetS+NAFLD type IV collagen 7S domain was measured.

RESULTS

MetS+NAFLD showed increased VLDL-mass, VLDL particle number, VLDL-triglyceride% and large VLDL-% (p<0.04). CETP activity tended to increase in MetS+NAFLD (p=0.058), while LPL activity was unchanged. Moreover, in MetS+NAFLD, adiponectin was decreased (p<0.001), and negatively correlated with VLDL-mass and VLDL particle number (p<0.05), independently of insulin-resistance. Within MetS+NAFLD group, despite greater insulin-resistance, patients with severe fibrosis showed lower plasma triglycerides, VLDL-mass, VLDL-triglyceride%, large VLDL-% and CETP activity (p<0.05), while type IV collagen was increased (p=0.009) and inversely correlated with large VLDL-% (p=0.045).

CONCLUSIONS

In MetS, NAFLD is associated with larger and triglyceride over-enriched circulating VLDLs, of greater atherogenicity. However, when NAFLD progresses to severe fibrosis, circulating VLDL features apparently improved, probably due to early alterations in hepatic synthetic function.

Effects of telmisartan on improving leptin resistance and inhibiting hepatic fibrosis in rats with non-alcoholic fatty liver disease

The present study aimed to investigate the impacts of telmisartan (TEL) on hepatic fibrosis, serum leptin, leptin protein in liver tissue and its mRNA expression level in rats with non-alcoholic fatty liver disease (NAFLD). Male Sprague Dawley rats were randomly divided into the control (N), model (M), polyene phosphatidylcholine (P) and TEL (T) groups. Group M and the intervention groups were given a high-fat diet for 12 weeks to induce NAFLD, followed by 4 weeks of intragastric administration of normal saline (1.0 ml/kg/day), polyene phosphatidylcholine (PPC; 123.1 mg/kg/day) and TEL (8 mg/kg/day). The liver tissue was then assessed for the NAFLD activity score and fibrosis score (FS), and serum biochemistry and leptin levels were determined. Additionally, leptin protein expression levels were examined by western blotting and the expression of leptin mRNA was investigated by reverse transcription-polymerase chain reaction. TEL significantly improved FS in rats (P<0.01) and was more effective than PPC. TEL significantly reduced the expression of serum leptin, as well as the expression levels of leptin protein and its mRNA in liver tissue (P<0.01); however, the effects of PPC were not significant (P>0.05). TEL reduced serum leptin, leptin protein and its mRNA in the liver tissue of NAFLD rats, and improved the pathological indicators of liver fibrosis.

Phyllanthus Niruri Standardized Extract Alleviates the Progression of Non-Alcoholic Fatty Liver Disease and Decreases Atherosclerotic Risk in Sprague-Dawley Rats

Non-alcoholic fatty liver disease (NAFLD) is one of the major global health issues, strongly correlated with insulin resistance, obesity and oxidative stress. The current study aimed to evaluate anti-NAFLD effects of three different extracts of Phyllanthus niruri (P. niruri). NAFLD was induced in male Sprague-Dawley rats using a special high-fat diet (HFD). A 50% methanolic extract (50% ME) exhibited the highest inhibitory effect against NAFLD progression. It significantly reduced hepatomegaly (16%) and visceral fat weight (22%), decreased NAFLD score, prevented fibrosis, and reduced serum total cholesterol (TC) (48%), low-density lipoprotein (LDL) (65%), free fatty acids (FFAs) (25%), alanine aminotransferase (ALT) (45%), alkaline phosphatase (ALP) (38%), insulin concentration (67%), homeostatic model assessment of insulin resistance (HOMA-IR) (73%), serum atherogenic ratios TC/high-density lipoprotein (HDL) (29%), LDL/HDL (66%) and (TC-HDL)/HDL (64%), hepatic content of cholesterol (43%), triglyceride (29%) and malondialdehyde (MDA) (40%) compared to a non-treated HFD group. In vitro, 50% ME of P. niruri inhibited α-glucosidase, pancreatic lipase enzymes and cholesterol micellization. It also had higher total phenolic and total flavonoid contents compared to other extracts. Ellagic acid and phyllanthin were identified as major compounds. These results suggest that P. niruri could be further developed as a novel natural hepatoprotective agent against NAFLD and atherosclerosis.

Type 2 diabetes mellitus and risk of hepatocellular carcinoma: spotlight on nonalcoholic fatty liver disease

The incidence of both type 2 diabetes mellitus (T2DM) and multiple cancer types are rapidly increasing worldwide. Several studies documented that T2DM is closely associated with an increased incidence of cancer. However, while some methodological considerations preclude a definitive association between T2DM and the risk of certain cancers, the relationship between T2DM and increased risk of incident hepatocellular carcinoma (HCC) remains significant even after adjustment for detection bias and reverse causation, indicating that such association is clinically reliable and robust. In addition, a number of observational studies also showed that T2DM is associated with higher mortality among persons with HCC. Some recent meta-analyses suggested that treatment with metformin may be associated with a lower risk of HCC, and may also beneficially influence HCC prognosis, whereas treatment with sulphonylureas or insulin seems to be related to a higher HCC risk. The underlying biological mechanisms linking T2DM and HCC are complex and difficult to elucidate, but the existence of close inter-connections among T2DM, obesity and nonalcoholic fatty liver disease (NAFLD) induces hepatic/systemic insulin resistance and causes the release of multiple pro-inflammatory cytokines, vasoactive factors and pro-oxidant molecules, which are all potentially implicated in the development and progression of HCC. In this clinical review, we discuss the epidemiological evidence linking T2DM to the risk of HCC. Moreover, we also briefly discuss the putative underlying mechanisms linking T2DM, NAFLD and HCC, and the potential effect of certain hypoglycemic agents on the risk of developing HCC.

Helianthus tuberosus (Jerusalem artichoke) tubers improve glucose tolerance and hepatic lipid profile in rats fed a high-fat diet

OBJECTIVES

To analyze the effects of feeding Helianthus tuberosus (HT) tubers on glucose tolerance and lipid profile in rats fed a high-fat diet (HFD).

METHODS

A normal HFD or HFD including 10 w/w% HT tubers (HFD + HT) was fed to F334/Jcl rats. After 10 weeks, organ weights, glucose tolerance, and lipid profile were analyzed.

RESULTS

The body weight, liver weight, and epidermal fat content in the HFD group were higher than those of the normal group, and similar to those of the HFD + HT group. The oral glucose tolerance test at 10 weeks revealed that the blood glucose level 30 min after beginning the test in the HFD + HT group was significantly lower than that in the HFD group. Liver triglyceride and total cholesterol levels in the HFD + HT group were significantly lower than those in the HFD group. Fecal triglyceride and total cholesterol levels in the HFD + HT group were higher than those in the HFD group. Histological analyses revealed that fat and glycogen accumulation increased in the HFD group, but decreased in the HFD + HT group.

CONCLUSIONS

These results indicate that HT tubers have anti-fatty liver effects based on improvements in glucose tolerance and the hepatic lipid profile.

Circular RNA Profiling and Bioinformatic Modeling Identify Its Regulatory Role in Hepatic Steatosis

Circular RNAs (circRNAs) exhibit a wide range of physiological and pathological activities. To uncover their role in hepatic steatosis, we investigated the expression profile of circRNAs in HepG2-based hepatic steatosis induced by high-fat stimulation. Differentially expressed circRNAs were subjected to validation using QPCR and functional analyses using principal component analysis, hierarchical clustering, target prediction, gene ontology (GO), and pathway annotation, respectively. Bioinformatic integration established the circRNA-miRNA-mRNA regulatory network so as to identify the mechanisms underlying circRNAs' metabolic effect. Here we reported that hepatic steatosis was associated with a total of 357 circRNAs. Enrichment of transcription-related GOs, especially GO: 0006355, GO: 004589, GO: 0045944, GO: 0045892, and GO: 0000122, demonstrated their specific actions in transcriptional regulation. Lipin 1 (LPIN1) was recognized to mediate the transcriptional regulatory effect of circRNAs on metabolic pathways. circRNA-miRNA-mRNA network further identified the signaling cascade of circRNA_021412/miR-1972/LPIN1, which was characterized by decreased level of circRNA_021412 and miR-1972-based inhibition of LPIN1. LPIN1-induced downregulation of long chain acyl-CoA synthetases (ACSLs) expression finally resulted in the hepatosteatosis. These findings identify circRNAs to be important regulators of hepatic steatosis. Transcription-dependent modulation of metabolic pathways may underlie their effects, partially by the circRNA_021412/miR-1972/LPIN1 signaling.

Non-alcoholic fatty liver disease: An expanded review

Non-alcoholic fatty liver disease (NAFLD) encompasses the simple steatosis to more progressive steatosis with associated hepatitis, fibrosis, cirrhosis, and in some cases hepatocellular carcinoma. NAFLD is a growing epidemic, not only in the United States, but worldwide in part due to obesity and insulin resistance leading to liver accumulation of triglycerides and free fatty acids. Numerous risk factors for the development of NAFLD have been espoused with most having some form of metabolic derangement or insulin resistance at the core of its pathophysiology. NAFLD patients are at increased risk of liver-related as well as cardiovascular mortality, and NAFLD is rapidly becoming the leading indication for liver transplantation. Liver biopsy remains the gold standard for definitive diagnosis, but the development of noninvasive advanced imaging, biochemical and genetic tests will no doubt provide future clinicians with a great deal of information and opportunity for enhanced understanding of the pathogenesis and targeted treatment. As it currently stands several medications/supplements are being used in the treatment of NAFLD; however, none seem to be the "magic bullet" in curtailing this growing problem yet. In this review we summarized the current knowledge of NAFLD epidemiology, risk factors, diagnosis, pathogenesis, pathologic changes, natural history, and treatment in order to aid in further understanding this disease and better managing NAFLD patients.

Roles of p53 in extrinsic factor-induced liver carcinogenesis

Liver cancer remains one of the most common human cancers with a high mortality rate. Therapies for hepatocellular carcinoma (HCC) remain ineffective, due to the heterogeneity of HCC with regard to both the etiology and mutation spectrum, as well as its chemotherapy resistant nature; thus surgical resection and liver transplantation remain the gold standard of patient care. The most common etiologies of HCC are extrinsic factors. Humans have multiple defense mechanisms against extrinsic factor-induced carcinogenesis, of which tumor suppressors play crucial roles in preventing normal cells from becoming cancerous. The tumor suppressor p53 is one of the most frequently mutated genes in liver cancer. p53 regulates expression of genes involved in cell cycle progression, cell death, and cellular metabolism to avert tumor development due to carcinogens. This review article mainly summarizes extrinsic factors that induce liver cancer and potentially have etiological association with p53, including aflatoxin B1, vinyl chloride, non-alcoholic fatty liver disease, iron overload, and infection of hepatitis viruses.

NAFLD as a Sexual Dimorphic Disease: Role of Gender and Reproductive Status in the Development and Progression of Nonalcoholic Fatty Liver Disease and Inherent Cardiovascular Risk

Nonalcoholic fatty liver disease (NAFLD) spans steatosis through nonalcoholic steatohepatis, cirrhosis, and hepatocellular carcinoma (HCC) associated with striking systemic features and excess cardiovascular and liver-related mortality. The pathogenesis of NAFLD is complex and multifactorial. Endocrine derangements are closely linked with dysmetabolic traits. For example, in animal and human studies, female sex is protected from dysmetabolism thanks to young individuals’ ability to partition fatty acids towards ketone body production rather than very low density lipoprotein (VLDL)-triacylglycerol, and to sex-specific browning of white adipose tissue. Ovarian senescence facilitates both the development of massive hepatic steatosis and the fibrotic progression of liver disease in an experimental overfed zebrafish model. Consistently, estrogen deficiency, by potentiating hepatic inflammatory changes, hastens the progression of disease in a dietary model of nonalcoholic steatohepatitis (NASH) developing in ovariectomized mice fed a high-fat diet. In humans, NAFLD more often affects men; and premenopausal women are equally protected from developing NAFLD as they are from cardiovascular disease. It would be expected that early menarche, definitely associated with estrogen activation, would produce protection against the risk of NAFLD. Nevertheless, it has been suggested that early menarche may confer an increased risk of NAFLD in adulthood, excess adiposity being the primary culprit of this association. Fertile age may be associated with more severe hepatocyte injury and inflammation, but also with a decreased risk of liver fibrosis compared to men and postmenopausal status. Later in life, ovarian senescence is strongly associated with severe steatosis and fibrosing NASH, which may occur in postmenopausal women. Estrogen deficiency is deemed to be responsible for these findings via the development of postmenopausal metabolic syndrome. Estrogen supplementation may at least theoretically protect from NAFLD development and progression, as suggested by some studies exploring the effect of hormonal replacement therapy on postmenopausal women, but the variable impact of different sex hormones in NAFLD (i.e., the pro-inflammatory effect of progesterone) should be carefully considered.

Pre-clinical and clinical investigations of metabolic zonation in liver diseases: The potential of microphysiology systems

The establishment of metabolic zonation within a hepatic lobule ascribes specific functions to hepatocytes based on unique, location-dependent gene expression patterns. Recently, there have been significant developments in the field of metabolic liver zonation. A little over a decade ago, the role of β-catenin signaling was identified as a key regulator of gene expression and function in pericentral hepatocytes. Since then, additional molecules have been identified that regulate the pattern of Wnt/β-catenin signaling within a lobule and determine gene expression and function in other hepatic zones. Currently, the molecular basis of metabolic zonation in the liver appears to be a 'push and pull' between signaling pathways. Such compartmentalization not only provides an efficient assembly line for hepatocyte functions but also can account for restricting the initial hepatic damage and pathology from some hepatotoxic drugs to specific zones, possibly enabling effective regeneration and restitution responses from unaffected cells. Careful analysis and experimentation have also revealed that many pathological conditions in the liver lobule are spatially heterogeneous. We will review current research efforts that have focused on examination of the role and regulation of such mechanisms of hepatocyte adaptation and repair. We will discuss how the pathological organ-specific microenvironment affects cell signaling and metabolic liver zonation, especially in steatosis, viral hepatitis, and hepatocellular carcinoma. We will discuss how the use of new human microphysiological platforms will lead to a better understanding of liver disease progression, diagnosis, and therapies. In conclusion, we aim to provide insights into the role and regulation of metabolic zonation and function using traditional and innovative approaches. Impact statement Liver zonation of oxygen tension along the liver sinusoids has been identified as a critical liver microenvironment that impacts specific liver functions such as intermediary metabolism of amino acids, lipids, and carbohydrates, detoxification of xenobiotics and as sites for initiation of liver diseases. To date, most information on the role of zonation in liver disease including, non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), cirrhosis, and hepatocellular carcinoma (HCC) have been obtained from animal models. It is now possible to complement animal studies with human liver, microphysiology systems (MPS) containing induced pluripotent stem cells engineered to create disease models where it is also possible to control the in vitro liver oxygen microenvironment to define the role of zonation on the mechanism(s) of disease progression. The field now has the tools to investigate human liver disease progression, diagnosis, and therapeutic development.

Inhibition of NAMPT aggravates high fat diet-induced hepatic steatosis in mice through regulating Sirt1/AMPKα/SREBP1 signaling pathway

BACKGROUND

Nonalcoholic fatty liver disease is one of the most common liver diseases in the world and is a typical hepatic manifestation of metabolic syndrome which is characterized with lipid accumulation in liver. Nicotinamide phosphoribosyltransferase (NAMPT) has been recently identified as an enzyme involved in nicotinamide adenine dinucleotide (NAD+) biosynthesis and plays an important role in cellular metabolism in variety of organs in mammals. The aim of this study was to investigate the effects of NAMPT on high fat diet-induced hepatic steatosis.

METHODS

Hepatic steatosis model was induced by high fat diet (HFD) in C57BL/6 mice in vivo. HepG2 and Hep1-6 hepatocytes were transfected with NAMPT vector plasmid or treated with NAMPT inhibitor FK866 and then incubated with oleic acid. Lipids accumulation was examined by HE staining or oil red staining. Quantitative RT-PCR and Western blot were used to measure expressions of the genes involved in lipogenic synthesis.

RESULTS

FK866 significantly promoted liver steatosis in the mice fed with HFD and hepatic lipid accumulation in vitro, accompanied by the increases of the expressions of lipogenic genes such as sterol regulatory element-binding protein 1 (SREBP1) and fatty acid synthase (FASN). Nicotinamide mononucleotide (NMN) and NAD+ significantly rescued the actions of FK866 in vitro. In contrast, overexpression of NAMPT in HepG2 and Hep1-6 hepatocytes ameliorated hepatic lipid accumulation. In addition, FK866 decreased the protein levels of Sirt1 and phospho-AMPKα in liver of the HFD fed mice. Furthermore, Resveratrol, a Sirt1 activator, significantly reduced lipogenic gene expressions, while EX-527, a Sirt1 specific inhibitor, had the opposite effects.

CONCLUSION

Our results demonstrated that inhibition of NAMPT aggravated the HFD- or oleic acid-induced hepatic steatosis through suppressing Sirt1-mediated signaling pathway. On the one hand, the inhibition of NAMPT reduced the production of NAD+ through inhibiting the NAD+ salvage pathway, resulting in the decrease of Sirt1 activity, and then attenuated the deacetylation of SREBP1 in which the inhibition of SREBP1 activity promoted the expressions of FASN and ACC. On the other hand, the reduced Sirt1 activity alleviated the activation of AMPKα to further enhance SREBP1 activities.

Impaired learning and memory in rats induced by a high-fat diet: Involvement with the imbalance of nesfatin-1 abundance and copine 6 expression

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease, resulting not only in liver dysfunction, glucose and lipid metabolism disorder, but also in neuropsychiatric damage. In the present study, a NAFLD rat model was established via feeding of a high-fat diet, and behaviour was observed via the open field test (OFT), the sucrose preference test (SPT), the elevated plus maze (EPM), the forced swimming test (FST) and the Morris water maze (MWM). The plasma concentrations of alanine aminotransferase (ALT), glucose, free fatty acid (FFA), total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were detected using chemiluminescence technique. The plasma levels of nesfatin-1, leptin and insulin were measured via enzyme-linked immunosorbent assay, and the protein expressions of p-glycogen synthase kinase-3β (GSK-3β), GSK-3β, p-β-catenin, β-catenin, cyclinD and copine 6 in the hippocampus and prefrontal cortex (PFC) were detected using western blotting. After 4 consecutive weeks of feeding with a high-fat diet, the rats showed obesity; increased plasma concentrations of ALT, glucose, FFA, TC, TG, HDL-C and LDL-C; decreased plasma levels of leptin and insulin; and inflammation and mild hepatocyte steatosis in the liver. Although there was no significant difference between groups with regard to performance in the OFT, EPM or FST, the NAFLD rats showed a decreased sucrose preference index in the SPT and impaired learning and memory in the MWM task. Moreover, the present study provides the first evidence of an increased plasma nesfatin-1 concentration in NAFLD rats, which was significantly correlated with plasma lipid concentrations and behavioural performance. Furthermore, copine 6 and p-β-catenin protein expression decreased and p-GSK-3β increased in the hippocampus and PFC of NAFLD rats. These results suggest that consuming of a high-fat diet for 4 consecutive weeks could successfully induce a NAFLD rat model. More importantly, these results provide the first evidence that impaired learning and memory in NAFLD rats was, at least partly, associated with increased plasma nesfatin-1 concentration and decreased copine 6 expression in the hippocampus and PFC.

Hydrothermal Duodenal Mucosal Resurfacing: Role in the Treatment of Metabolic Disease

The duodenum has become recognized as a metabolic signaling center that is involved in regulating insulin action and, therefore, insulin resistance states such as type 2 diabetes. Bariatric surgery and other manipulations of the upper intestine, in particular the duodenum, have shown that limiting nutrient exposure or contact in this key region exerts powerful metabolic effects. Early human clinical trial data suggest that endoscopic hydrothermal duodenal mucosal resurfacing is well tolerated in human subjects and has an acceptable safety profile. This article describes the rationale for this endoscopic approach and its early human use, including safety, tolerability, and early efficacy.

Towards a systems approach for chronic diseases, based on health state modeling

Rising pressure from chronic diseases means that we need to learn how to deal with challenges at a different level, including the use of systems approaches that better connect across fragments, such as disciplines, stakeholders, institutions, and technologies. By learning from progress in leading areas of health innovation (including oncology and AIDS), as well as complementary indications (Alzheimer's disease), I try to extract the most enabling innovation paradigms, and discuss their extension to additional areas of application within a systems approach. To facilitate such work, a Precision, P4 or Systems Medicine platform is proposed, which is centered on the representation of health states that enable the definition of time in the vision to provide the right intervention for the right patient at the right time and dose. Modeling of such health states should allow iterative optimization, as longitudinal human data accumulate. This platform is designed to facilitate the discovery of links between opportunities related to a) the modernization of diagnosis, including the increased use of omics profiling, b) patient-centric approaches enabled by technology convergence, including digital health and connected devices, c) increasing understanding of the pathobiological, clinical and health economic aspects of disease progression stages, d) design of new interventions, including therapies as well as preventive measures, including sequential intervention approaches. Probabilistic Markov models of health states, e.g. those used for health economic analysis, are discussed as a simple starting point for the platform. A path towards extension into other indications, data types and uses is discussed, with a focus on regenerative medicine and relevant pathobiology.

Short article: A randomized-controlled study of sitagliptin for treating diabetes mellitus complicated by nonalcoholic fatty liver disease

BACKGROUND

This study aimed to evaluate the efficacy and safety of sitagliptin for treating Chinese patients with type 2 diabetes mellitus (T2DM) with nonalcoholic fatty liver disease (NAFLD).

METHODS

In total, 72 Chinese T2DM patients with NAFLD were divided randomly into two groups of 36 patients each group. All 72 patients were assigned to receive either sitagliptin or diet and exercise for 52 weeks between January 2013 and December 2015. The outcomes' measurements included serum levels of hemoglobin A1c, fasting plasma glucose, aspartate aminotransferase, and alanine aminotransferase.

RESULTS

Seventy patients completed the study. Sitagliptin showed greater efficacy than the diet and exercise in decreasing the hemoglobin A1c and fasting plasma glucose levels at weeks 13, 26, 39, and 52. In addition, no significant changes in the average aspartate aminotransferase and alanine aminotransferase levels were found during the 52-week follow-up in both the sitagliptin and the control groups.

CONCLUSION

The results of this study indicate that sitagliptin is an effective and safe treatment for patients with T2DM and NAFLD.

Effect of orlistat on periostin, adiponectin, inflammatory markers and ultrasound grades of fatty liver in obese NAFLD patients

Orlistat is recommended in the treatment of obesity, which is an independent risk factor for nonalcoholic fatty liver disease (NAFLD). The reported findings of orlistat in NAFLD are divisive. Recently, periostin is identified as an important regulatory molecule in the pathogenesis of obesity-induced fatty liver. Therefore, this study aimed to evaluate the potential effects of orlistat in the treatment of NAFLD. A 16-week prospective observational study was conducted, with obese NAFLD patient (n=77) receiving orlistat (120 mg capsules, three times a day) with hypocaloric diet or hypocaloric diet only. Grades of fatty liver were determined using ultrasound (US) echogenicity of liver; serum levels of periostin, adiponectin, tumor necrosis factor (TNF)-α and interleukin-6 were determined using ELISA kits at 0 and 16 weeks. Correlations of US grades of fatty liver with these biomarkers were also determined. Orlistat significantly reversed the US grades of fatty liver (P=0.016), decreased serum levels of periostin (P=0.030) and TNF-α (P=0.040), and increased serum adiponectin levels (P<0.001) when compared with hypocaloric diet only. Serum interleukin-6 levels were not found to be significantly different in both groups after the treatment. In the orlistat group, the degree of reduction in grades of fatty liver was found to be positively correlated with the changes in serum levels of periostin (rs=0.306, P=0.041) and adiponectin (rs=0.314, P=0.036), whereas the associations were insignificant with the change in serum levels of TNF-α (rs=0.053, P=0.729). Mild gastrointestinal side effects (20%) were reported in the orlistat group. In conclusion, orlistat is effective in the treatment of NAFLD patients without fibrosis. This study demonstrated a positive association between the reduction of fatty infiltration in the liver and the changes in serum levels of periostin and adiponectin in obese NAFLD patients.

Effects of Natural Products on Fructose-Induced Nonalcoholic Fatty Liver Disease (NAFLD)

As a sugar additive, fructose is widely used in processed foods and beverages. Excessive fructose consumption can cause hepatic steatosis and dyslipidemia, leading to the development of metabolic syndrome. Recent research revealed that fructose-induced nonalcoholic fatty liver disease (NAFLD) is related to several pathological processes, including: (1) augmenting lipogenesis; (2) leading to mitochondrial dysfunction; (3) stimulating the activation of inflammatory pathways; and (4) causing insulin resistance. Cellular signaling research indicated that partial factors play significant roles in fructose-induced NAFLD, involving liver X receptor (LXR)α, sterol regulatory element binding protein (SREBP)-1/1c, acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), stearoyl-CoA desaturase (SCD), peroxisome proliferator–activated receptor α (PPARα), leptin nuclear factor-erythroid 2-related factor 2 (Nrf2), nuclear factor kappa B (NF-κB), tumor necrosis factor α (TNF-α), c-Jun amino terminal kinase (JNK), phosphatidylinositol 3-kinase (PI3K) and adenosine 5′-monophosphate (AMP)-activated protein kinase (AMPK). Until now, a series of natural products have been reported as regulators of NAFLD in vivo and in vitro. This paper reviews the natural products (e.g., curcumin, resveratrol, and (−)-epicatechin) and their mechanisms of ameliorating fructose-induced NAFLD over the past years. Although, as lead compounds, natural products usually have fewer activities compared with synthesized compounds, it will shed light on studies aiming to discover new drugs for NAFLD.

Metabolomic Fingerprinting in the Comprehensive Study of Liver Changes Associated with Onion Supplementation in Hypercholesterolemic Wistar Rats

The consumption of functional ingredients has been suggested to be a complementary tool for the prevention and management of liver disease. In this light, processed onion can be considered as a source of multiple bioactive compounds with hepatoprotective properties. The liver fingerprint of male Wistar rats (n = 24) fed with three experimental diets (control (C), high-cholesterol (HC), and high-cholesterol enriched with onion (HCO) diets) was obtained through a non-targeted, multiplatform metabolomics approach to produce broad metabolite coverage. LC-MS, CE-MS and GC-MS results were subjected to univariate and multivariate analyses, providing a list of significant metabolites. All data were merged in order to figure out the most relevant metabolites that were modified by the onion ingredient. Several relevant metabolic changes and related metabolic pathways were found to be impacted by both HC and HCO diet. The model highlighted several metabolites (such as hydroxybutyryl carnitine and palmitoyl carnitine) modified by the HCO diet. These findings could suggest potential impairments in the energy−lipid metabolism, perturbations in the tricarboxylic acid cycle (TCA) cycle and β-oxidation modulated by the onion supplementation in the core of hepatic dysfunction. Metabolomics shows to be a valuable tool to evaluate the effects of complementary dietetic approaches directed to hepatic damage amelioration or non-alcoholic fatty liver disease (NAFLD) prevention.

Steatosis influences the clinical profiles and long-term outcomes of interferon-treated chronic hepatitis C and liver cirrhosis patients

Objective: This study aimed to assess the relationship between steatosis and long-term outcomes of patients with chronic hepatitis C (CH) and liver cirrhosis (LC). Patients and methods: The study population included 282 subjects with CH or LC who underwent liver biopsy at our institute. All patients achieved a sustained virological response (SVR) to interferon (IFN). Clinical characteristics, including age, gender and body mass index (BMI), were compared. The liver biopsy specimens of all patients were examined and scores were assigned to indicate the severity of each of the following features: inflammatory cell infiltration in the periportal, parenchymal and portal areas; F (fibrosis) stage; portal sclerotic change; perivenular fibrosis; pericellular fibrosis; bile duct damage; hepatic steatosis. Results: Of the 282 patients, 112 (39.7%) were free of steatosis. The other 170 patients (60.3%) had steatosis. The blood biochemical parameters of the patients with hepatic steatosis were significantly poorer than those of patients free of steatosis. Inflammatory cell infiltration and F stage were both significantly more severe in patients with than in those without steatosis. The incidences of hepatocellular carcinoma differed significantly between the two groups. However, the incidences of hepatocellular carcinoma did not differ significantly between the groups with BMI above and below 25. Conclusion: We consider hepatic steatosis to potentially affect the blood biochemical parameters and clinical profiles of Japanese patients with CH due to hepatitis virus type C. Patients with this form of CH showed favorable clinical responses to IFN. Furthermore, fibrosis and steatosis appear to affect the long-term outcomes of these patients. However, BMI alone cannot be used to predict HCC development.

Peretinoin as an adjuvant therapy for hepatocellular carcinoma

The current curative treatment modalities for hepatocellular carcinoma (HCC) are unfortunately fraught with high rates of HCC recurrence. Hence there is a need to prevent or reduce HCC recurrence after initial curative therapy. Peretinoin is a synthetic oral retinoid showing significant reduction in the incidence of recurrent or new HCC in patients who had received curative HCC therapy. Areas covered: Peretinoin is analysed against the background of molecular pathogenesis of the different causes of HCC. Publications related to peretinoin since 1996 are reviewed, covering clinical characteristics, safety and tolerance profile as well as the current status of clinical development. Expert commentary: Early phase studies are promising but we need to await the results of the ongoing phase III study of peretinoin in hepatitis C related HCC. Long term impact of peretinoin may be diminished by the foreseeable near eradication of hepatitis C by the direct acting antivirals.

The economic and clinical burden of nonalcoholic fatty liver disease in the United States and Europe

Nonalcoholic fatty liver disease (NAFLD) is a major cause of chronic liver disease. There is uncertainty around the economic burden of NAFLD. We constructed a steady-state prevalence model to quantify this burden in the United States and Europe. Five models were constructed to estimate the burden of NAFLD in the United States and four European countries. Models were built using a series of interlinked Markov chains, each representing age increments of the NAFLD and the general populations. Incidence and remission rates were calculated by calibrating against real-world prevalence rates. The data were validated using a computerized disease model called DisMod II. NAFLD patients transitioned between nine health states (nonalcoholic fatty liver, nonalcoholic steatohepatitis [NASH], NASH-fibrosis, NASH-compensated cirrhosis, NASH-decompensated cirrhosis, hepatocellular carcinoma, liver transplantation, post-liver transplant, and death). Transition probabilities were sourced from the literature and calibrated against real-world data. Utilities were obtained from NAFLD patients using the Short Form-6D. Costs were sourced from the literature and local fee schedules. In the United States, over 64 million people are projected to have NAFLD, with annual direct medical costs of about $103 billion ($1,613 per patient). In the Europe-4 countries (Germany, France, Italy, and United Kingdom), there are ∼52 million people with NAFLD with an annual cost of about €35 billion (from €354 to €1,163 per patient). Costs are highest in patients aged 45-65. The burden is significantly higher when societal costs are included.

CONCLUSION

The analysis quantifies the enormity of the clinical and economic burdens of NAFLD, which will likely increase as the incidence of NAFLD continues to rise. (Hepatology 2016;64:1577-1586).