Nonalcoholic fatty liver disease and nonalcoholic steatohepatitis in Japan

Application of artificial intelligence techniques for non-alcoholic fatty liver disease diagnosis: A systematic review (2005-2023)

BACKGROUND AND OBJECTIVES

Non-alcoholic fatty liver disease (NAFLD) is a common liver disease with a rapidly growing incidence worldwide. For prognostication and therapeutic decisions, it is important to distinguish the pathological stages of NAFLD: steatosis, steatohepatitis, and liver fibrosis, which are definitively diagnosed on invasive biopsy. Non-invasive ultrasound (US) imaging, including US elastography technique, and clinical parameters can be used to diagnose and grade NAFLD and its complications. Artificial intelligence (AI) is increasingly being harnessed for developing NAFLD diagnostic models based on clinical, biomarker, or imaging data. In this work, we systemically reviewed the literature for AI-enabled NAFLD diagnostic models based on US (including elastography) and clinical (including serological) data.

METHODS

We performed a comprehensive search on Google Scholar, Scopus, and PubMed search engines for articles published between January 2005 and June 2023 related to AI models for NAFLD diagnosis based on US and/or clinical parameters using the following search terms: "non-alcoholic fatty liver disease", "non-alcoholic steatohepatitis", "deep learning", "machine learning", "artificial intelligence", "ultrasound imaging", "sonography", "clinical information".

RESULTS

We reviewed 64 published models that used either US (including elastography) or clinical data input to detect the presence of NAFLD, non-alcoholic steatohepatitis, and/or fibrosis, and in some cases, the severity of steatosis, inflammation, and/or fibrosis as well. The performances of the published models were summarized, and stratified by data input and algorithms used, which could be broadly divided into machine and deep learning approaches.

CONCLUSION

AI models based on US imaging and clinical data can reliably detect NAFLD and its complications, thereby reducing diagnostic costs and the need for invasive liver biopsy. The models offer advantages of efficiency, accuracy, and accessibility, and serve as virtual assistants for specialists to accelerate disease diagnosis and reduce treatment costs for patients and healthcare systems.

Risk Factors of Non-alcoholic Fatty Liver Disease in the Iranian Adult Population: A Systematic Review and Meta-analysis

Context: Non-alcoholic fatty liver disease (NAFLD) is progressing considerably worldwide. Identifying the risk factors of NAFLD is a critical step in preventing its progression. Methods: In November 2022, two independent researchers studied seven databases, including PubMed, ISI/WoS, ProQuest, Scopus, SID, Magiran, and Google Scholar, and reference list of relevant articles, searching studies that assessed NAFLD risk factors in the Iranian adult population. Heterogeneity between studies was assessed by Cochran’s test and its composition using I2 statistics. A random-effects model was used when heterogeneity was observed; otherwise, a fixed-effects model was applied. Egger’s regression test and Trim-and-Fill analysis were used to assess publication bias. Comprehensive Meta-analysis software (version 3) was used for the analyses of the present study. Results: The results of this study showed significant associations between NAFLD with age [n = 15, odds ratio (OR) = 2.12, 95% CI: 1.79 - 2.51], body mass index (n = 46, OR = 5.00, 95% CI: 3.34 - 7.49), waist circumference (n = 20, OR = 6.37, 95% CI: 3.25 - 12.48), waist-to-hip ratio (n = 17, OR = 4.72, 95% CI: 3.93 - 5.66), total cholesterol (n = 39, OR = 1.80, 95% CI: 1.52 - 2.13), high-density lipoprotein (n = 37, OR = 0.53, 95% CI: 0.44 - 0.65), low-density lipoprotein (n = 31, OR = 1.68, 95% CI: 1.38 - 2.05), triglyceride (n = 31, OR = 3.21, 95% CI: 2.67 - 3.87), alanine aminotransferase (n = 26, OR = 4.06, 95% CI: 2.94 - 5.62), aspartate aminotransferase (n = 27, OR = 2.16, 95% CI: 1.50 - 3.12), hypertension (n = 13, OR = 2.53, 95% CI: 2.32 - 2.77), systolic blood pressure (n = 13, OR = 1.83, 95% CI: 1.53 - 2.18), diastolic blood pressure (n = 14, OR = 1.80, 95% CI: 1.48 - 2.20), fasting blood sugar (n = 31,OR = 2.91, 95% CI: 2.11- 4.01), homeostatic model assessment for insulin resistance (n = 5, OR = 1.92, 95% CI: 1.48 - 2.59), diabetes mellitus (n = 15, OR = 3.04, 95% CI: 2.46 - 3.75), metabolic syndrome (n = 10, OR = 3.56, 95% CI: 2.79 - 4.55), and physical activity (n = 11, OR = 0.32, 95% CI: 0.24 - 0.43) (P < 0.05). Conclusions: In conclusion, several factors are significantly associated with NAFLD. However, anthropometric indices had the strongest relationship with NAFLD in the Iranian adult population.

Two differentially methylated region networks in nonalcoholic fatty liver disease, viral hepatitis, and hepatocellular carcinoma

Background

We previously reported that two differentially methylated region (DMR) networks identified by DMR and co-methylation analyses are strongly correlated with the fibrosis stages of nonalcoholic fatty liver disease (NAFLD). In the current study, we examined these DMR networks in viral hepatitis and hepatocellular carcinoma (HCC).

Methods

We performed co-methylation analysis of DMRs using a normal dataset (GSE48325), two NAFLD datasets (JGAS000059 and GSE31803), and two HCC datasets (GSE89852 and GSE56588). The dataset GSE60753 was used for validation.

Results

One DMR network was clearly observed in viral hepatitis and two HCC populations. Methylation levels of genes in this network were higher in viral hepatitis and cirrhosis, and lower in HCC. Fatty acid binding protein 1 (FABP1), serum/glucocorticoid regulated kinase 2 (SGK2), and hepatocyte nuclear factor 4 α (HNF4A) were potential hub genes in this network. Increased methylation levels of the FABP1 gene may be correlated with reduced protection of hepatocytes from oxidative metabolites in NAFLD and viral hepatitis. The decreased methylation levels of SGK2 may facilitate the growth and proliferation of HCC cells. Decreased methylation levels of HNF4A in HCC may be associated with tumorigenesis. The other DMR network was observed in NAFLD, but not in viral hepatitis or HCC. This second network included genes involved in transcriptional regulation, cytoskeleton organization, and cellular proliferation, which are specifically related to fibrosis and/or tumorigenesis in NAFLD.

Conclusions

Our results suggest that one DMR network was associated with fibrosis and tumorigenesis in both NAFLD and viral hepatitis, while the other network was specifically associated with NAFLD progression. Furthermore, FABP1, SGK2, and HNF4A are potential candidate targets for the prevention and treatment of HCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02360-4.

The association between major dietary patterns with the risk of non-alcoholic fatty liver disease, oxidative stress and metabolic parameters: A case-control study

Purpose

Non-alcoholic fatty liver disease (NAFLD) is caused by the increase of fat in the liver. The present study aimed to study the association between different dietary patterns and NAFLD in adults.

Methods

This study included 121 adult patients with NAFLD and 119 non-NAFLD. Dietary intake was calculated by a 168-item food frequency questionnaire. Biochemical markers were measured. Dietary patterns were determined by factor analysis. The association between dietary patterns and NAFLD was evaluated using multiple logistic regression analysis.

Results

Two dietary patterns (healthy, western) were recognized in participants. Western dietary pattern was related with 72 percent increase in the odds of NAFLD (OR: 1.72; 95% CI: 1.32,2.14), after adjustment for covariates. Healthy dietary pattern was associated with 38 percent lower odds of NAFLD (OR: 0.38; 95% CI: 0.11, 0.65). Adherence to the western diet was related to 0.486 greater amounts of ALT, 3.248 mg/dl higher levels of FBS, and 3.989 mg/dl greater amounts of TG and 2.354 mg/dl greater amounts of MDA after adjusting for confounding factors (p > 0.001, p = 0.042, p > 0.001, p = 0.036 respectively). The healthy dietary pattern score was negatively associated with FBS and Cholesterol and TG levels (p = 0.035, p = 0.048, and p = 0.025), respectively. Moreover, it was associated with 3.211 mg/dl higher levels of TAC (p = 0.049).

Conclusions

There is a significant relationship between dietary patterns and non-alcoholic fatty liver disease. Adherence to a western dietary pattern is related to an increase in non-alcoholic fatty liver disease.

Hepatocellular carcinoma diagnosis using a novel electrochemiluminescence immunoassay targeting serum IgM-free AIM

BACKGROUND

Recent increases in the number of patients with non-alcoholic steatohepatitis (NASH) warrant the identification of biomarkers for early detection of hepatocellular carcinoma (HCC) associated with NASH (NASH-HCC). IgM-free apoptosis inhibitor of macrophage (AIM), which generally associates with IgM in blood and exerts its biological function by dissociation from IgM, may serve as an effective biomarker for NASH-HCC. Here, we established a fully automatic and high-throughput electrochemiluminescence immunoassay (ECLIA) to measure IgM-free AIM and investigated its efficacy in diagnosing NASH-HCC and viral HCC.

METHODS

IgM-free AIM levels were measured in 212 serum samples from patients with, or without, HCC related to NASH, hepatitis B virus, and hepatitis C virus, using ECLIA. We also developed an ECLIA for measuring both IgM-free and IgM-bound AIM and investigated the existing form of AIM in blood by size-exclusion chromatography.

RESULTS

IgM-free AIM levels were significantly higher in the HCC group than in the non-HCC group, regardless of the associated pathogenesis. Moreover, the area under the receiver operating curve for IgM-free AIM was greater than that for conventional HCC biomarkers, alpha-fetoprotein or des-γ-carboxy prothrombin, regardless of the cancer stage. ECLIA counts of IgM-free AIM derived from samples fractionated by size-exclusion chromatography were significantly higher in patients with NASH-HCC than in healthy volunteers and in patients with non-alcoholic fatty liver and NASH.

CONCLUSIONS

Serum IgM-free AIM may represent a universal HCC diagnostic marker superior to alpha-fetoprotein or des-γ-carboxy prothrombin. Our newly established ECLIA could contribute to further clinical studies on AIM and in vitro HCC diagnosis.

The Ability of the Framingham Steatosis Index (FSI) to Predict Non-alcoholic Fatty Liver Disease (NAFLD): A Cohort Study

BACKGROUND

The utilization of indexes for the diagnosis of non-alcoholic fatty liver disease (NAFLD) can be valuable. This study was conducted to determine the ability of the Framingham steatosis index (FSI) to distinguish between people with NAFLD and those without and to predict people at risk of NAFLD to establish the need for lifestyle modifications in such individuals.

METHODS

Our study was conducted in two phases from 2009-2010 (phase I) to 2016-2017 (phase II). A total of 4670 people in northern Iran were included. NAFLD was diagnosed by ultrasound. The FSI was calculated based on age, sex, hypertension, diabetes mellitus status, liver enzyme levels and triglyceride levels. Receiver operating characteristic (ROC) analysis was conducted to determine the discriminatory and predictive abilities of the FSI. To remove the confounding effects of potential mediators, logistic regression was performed in which NAFLD was considered the outcome and the FSI as the predictor.

RESULTS

The odds ratios of the FSI when the outcome was the prevalence of NAFLD in phase I and when the outcome was new cases of NAFLD from 2009-2010 to 2016-2017 were 4.909 (4.243-5.681) and 2.453 (2.024-2.972), respectively (P<0.001). The areas under the curve (AUCs) for the discriminatory and predictive abilities of the FSI were 0.8421 (95% CI: 0.8314-0.8527) and 0.7093 (95% CI: 0.6863-0.7322), respectively.

CONCLUSION

The FSI has a strong ability to diagnose NAFLD while it has an acceptable ability to predict the occurrence of new cases of NAFLD.

Characteristic Features of Nonalcoholic Fatty Liver Disease in Japan with a Focus on the Roles of Age, Sex and Body Mass Index

This review provides an update on the characteristics of nonalcoholic fatty liver disease (NAFLD), with a focus on the effects of age, sex, and body mass index. Age is a risk factor for NAFLD progression; however, extremely old patients have unique features, namely, the associations between metabolic comorbidities and NAFLD are weaker and NAFLD is not a risk factor for mortality. The prevalence of NAFLD is higher in men than in premenopausal women, whereas the reverse is true after menopause. Thus, before menopause, estrogen may have protective effects against NAFLD. Our hospital data showed that over 25% of male patients with NAFLD and almost 40% of female patients with NAFLD, especially elderly patients, were nonobese. Although histological steatosis and activity were associated with body mass index, the prevalence of nonalcoholic steatohepatitis was not. The prevalence of advanced fibrosis showed a significant sex difference. Advanced fibrosis was significantly more frequent among severely obese men but the prevalence was lower among severely obese women. This difference could be because a substantial proportion of severely obese women were premenopausal; thus, estrogen may have much stronger effects on the development of fibrosis than on obesity. Further studies are required to develop tailored management strategies.

Effect of ipragliflozin on liver function in Japanese type 2 diabetes mellitus patients: subgroup analysis of a 3-year post-marketing surveillance study (STELLA-LONG TERM)

The STELLA-LONG TERM prospective post-marketing surveillance study assessed ipragliflozin in Japanese patients with type 2 diabetes mellitus (T2DM). This subgroup analysis of patients with liver impairment used the final 3-year results. Data on patients, adverse drug reactions (ADRs), and changes in glycemic parameters and liver enzymes (aspartate aminotransferase [AST], alanine aminotransferase [ALT], gamma-glutamyl transpeptidase [γ-GTP] and alkaline phosphatase [ALP]) were collected, and the fatty liver index (FLI) was calculated. In the effectiveness analysis (n = 8,763), baseline liver function was normal in 2,605 patients (ALT <31/<21 U/L [men/women]) and abnormal in 3,277 (ALT ≥31/≥21 U/L). The abnormal liver function group had higher mean body weight and BMI than the normal liver function group (p < 0.001). In the safety analysis (n = 11,051), urinary tract infections, genital infections and hepatic disorders were more common in the abnormal than normal liver function group (2.25% vs. 1.07%; 1.78% vs. 1.14% and 1.85% vs. 1.01%). In the abnormal liver function group, there were significant (p < 0.001) decreases from baseline at 36 months in AST and ALT (from 38.8 and 53.7 U/L to 29.3 and 37.7 U/L, respectively), γ-GTP (from 75.4 to 51.7 U/L) and ALP (from 254.8 to 234.5 U/L), which were greater than in the normal liver function group. FLI reductions at 36 months were significant (p < 0.001) in subgroups with baseline FLI of ≥30 or ≥60. In conclusion, ipragliflozin improved liver function over 3 years in patients with impaired liver function, although ADRs occurred more frequently than in the normal liver function group.

Effects of non-linear resistance training and curcumin supplementation on the liver biochemical markers levels and structure in older women with non-alcoholic fatty liver disease

BACKGROUND

With increasing age, non-alcoholic fatty liver disease is very common among women with low levels of physical activity. Nonlinear resistance training is one of the new methods to help patients who have low levels of physical activity. Curcumin is an herbal supplement that has anti-inflammatory effects. The present study aimed to examine the effects of nonlinear resistance training and curcumin supplementation on the liver structure and biochemical markers in obese older women with non-alcoholic fatty liver disease.

METHODS

Forty-five obese women with non-alcoholic fatty liver disease were randomly assigned into resistance training (RT), curcumin supplement (C), resistance training with curcumin supplement (RTC), and placebo (P) groups. The RT and RTC groups received 12-weeks of nonlinear resistance training while the C and P groups had a normal sedentary lifestyle. Daily, the C and RTC groups received a curcumin capsule while the P and RT groups were given a placebo capsule. Blood sampling and ultrasonography were taken before and after the protocol.

RESULTS

Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels significantly decreased in the RT and RTC groups (P ≤ 0.05) but not in the C and P groups (P > 0.05). Alkaline phosphatase (ALP), total bilirubin (TB) levels, platelet counts (PLT), and liver structure did not significantly change in all groups (P > 0.05). Resistance training alone and with curcumin supplementation could significantly improve liver function while taking curcumin alone did not have any significant effect on it.

CONCLUSION

12-week non-linear resistance training has beneficial effects on non-alcoholic fatty liver disease in older obese women.

Practical Use of Transient Elastography in Screening for Nonalcoholic Steatohepatitis in a Japanese Population

Background and Aims: Fatty infiltration of liver may induce insulin resistance (IR), and a proportion of patients with nonalcoholic fatty liver disease (NAFLD) is diagnosed with nonalcoholic steatohepatitis. Transient elastography is gaining popularity as a means of non-invasively determining both liver stiffness (fibrosis level) and degree of fatty infiltration, expressed as controlled attenuation parameter (CAP) value. Methods: The aims of this study were to investigate the association between IR and level of fatty liver, and to identify the group at a greater risk of nonalcoholic steatohepatitis using transient elastography and other noninvasive fibrosis markers. A total of 169 patients without chronic hepatitis B and C were analyzed. Results: The CAP value was significantly associated with IR (HOMA-IR ≥2.5; AUROC = 0.81), and the optimal cut-off to discriminate IR was 264 dB/m. The liver stiffness measurement and aspartate aminotransferase-to-platelet ratio index values were significantly higher for CAP ≥264 than in CAP <264. The 9 patients among the overall 169 patients (5.3%) and among the 102 NAFLD patients (8.8%) who showed ≥264 dB and ≥7.0 kPa in transient elastography could represent good candidates for liver biopsy. Conclusions: Evaluation of NAFLD based on CAP values was useful in diagnosing IR. About 9% of NAFLD patients in a Japanese outpatient clinic with a few metabolic complications might be considered good candidates for liver biopsy to confirm nonalcoholic steatohepatitis.

Trends in hepatocellular carcinoma due to non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide and is associated with hepatocellular carcinoma (HCC), the most frequent malignant liver tumor. The increasing prevalence of obesity and diabetes is influencing the epidemiology of HCC with the most dramatic increases in NAFLD-related HCC seen in Western countries. Although cirrhosis is the major risk factor for HCC in NAFLD, there is increasing recognition that NAFLD-HCC occurs in the absence of cirrhosis. Areas covered: The epidemiology of NAFLD related HCC and its impact on changing the incidence of HCC globally. We overview risk factors for NAFLD-HCC in the presence and absence of cirrhosis and examine trends in liver transplantation (LT) related to NAFLD-HCC. Expert commentary: The incidence of NAFLD-related cirrhosis will continue to rise globally in parallel with risk factors of obesity and diabetes. Consequently, NAFLD-related HCC will become an increasingly important cause of liver-related morbidity and mortality and a common indication for LT worldwide. Further identification of risk factors for NAFLD-HCC and effective treatments for NAFLD are required to reduce this future burden of disease.

AIM-deficient mouse fed a high-trans fat, high-cholesterol diet: a new animal model for nonalcoholic fatty liver disease

Owing to changes in lifestyle, nonalcoholic fatty liver disease (NAFLD) is becoming a common form of chronic liver injury. NAFLD comprises a wide variety of disease stages, from simple steatosis to nonalcoholic steatohepatitis, which is a risk factor for the development of hepatocellular carcinoma (HCC). Because animal models for NAFLD are needed to investigate the precise pathogenesis, we aimed to establish a new mouse model employing mice deficient for apoptosis inhibitor of macrophage (AIM^−/−), which exhibit accelerated lipid storage in the liver and high susceptibility to developing HCC in response to a high-fat diet (HFD). AIM^−/− mice were fed the D09100301 diet, which contains 40 kcal% fat (trans fat 30 kcal%), high cholesterol (2%), and 40 kcal% carbohydrates (20 kcal% fructose), and then features of obesity and NAFLD including steatosis, inflammation, fibrosis, and HCC development were analyzed. Although a comparable grade of liver steatosis was promoted in AIM^−/− mice by the D09100301 diet and the standard HFD (60 kcal% largely lard fat), significantly less lipid storage in visceral fat was observed when the mice were fed the D09100301 diet. Accelerated liver inflammation was promoted by the D09100301 diet compared with the HFD, but interestingly, HCC development was decreased in mice fed the D09100301 diet. Our findings suggest that AIM^−/− mice fed the D09100301 diet exhibited a phenotype that resembled nonobese NAFLD patients and thus could be an appropriate tool to study the pathophysiology by which obesity increases the risk of HCC.

Role of MicroRNAs in the Development of Hepatocellular Carcinoma in Nonalcoholic Fatty Liver Disease

Hepatocellular carcinoma (HCC) is a prevalent liver malignancy that can be developed from nonalcoholic fatty liver disease (NAFLD). Numerous pathophysiological alterations, including insulin resistance, specific cytokine release, oxidative stress, and mitochondrial damage, are involved in the transition of NAFLD to cirrhosis and HCC. MicroRNAs, as post-transcriptional modulators, play a critical role in the pathogenesis of NAFLD-related HCC by regulating lipid metabolism, glucose homeostasis, cell proliferation, apoptosis, migration, and differentiation. This review summarizes the current progress of microRNAs in the risk and prognosis of NAFLD-related HCC. Anat Rec, 302:193-200, 2019. © 2018 Wiley Periodicals, Inc.

The polyherbal drug GGEx18 from Laminaria japonica, Rheum palmatum, and Ephedra sinica inhibits hepatic steatosis and fibroinflammtion in high-fat diet-induced obese mice

ETHNOPHARMACOLOGICAL RELEVANCE

The herbal composition Gyeongshingangjeehwan 18 (GGEx18), composed of Rheum palmatum L. (Polygonaceae), Laminaria japonica Aresch (Laminariaceae), and Ephedra sinica Stapf (Ephedraceae), is used as an antiobesity drug in Korean clinics. The constituents of GGEx18 have traditionally been reported to inhibit obesity and related metabolic diseases such as insulin resistance and dyslipidemia.

OBJECTIVE

This study investigated the effects of GGEx18 on nonalcoholic fatty liver disease (NAFLD) in mice fed a high-fat diet (HFD) and the underlying cellular and molecular mechanisms involved.

METHODS

C57BL/6 J mice were fed either a low-fat diet (LFD), an HFD, or an HFD supplemented with GGEx18 (125, 250, or 500 mg/kg of body weight/day). After 13 weeks, blood analyses, histology, immunohistochemistry, and real-time PCR were performed to assess NAFLD development in these mice.

RESULTS

Mice fed an HFD had increases in body weight, epididymal adipose tissue mass, adipocyte size, and adipose expression of inflammation-related genes compared with those fed an LFD. These increases were ameliorated in mice treated with 500 mg/kg/day GGEx18 without affecting food consumption profiles. GGEx18 not only decreased serum levels of triglycerides, free fatty acids, and alanine aminotransferase, but also decreased hepatic lipid accumulation, numbers of mast cells and α-smooth muscle actin-positive cells, and collagen levels induced by an HFD. Consistent with the histological data, the hepatic expression of lipogenesis-, inflammation-, and fibrosis-related genes was lower, while hepatic fatty acid β-oxidation-related gene expression was higher, in mice receiving GGEx18 compared to mice fed only the HFD.

DISCUSSION AND CONCLUSION

These results indicate that GGEx18 attenuates visceral obesity and NAFLD, in part by altering the expression of genes involved in hepatic steatosis and fibroinflammation in HFD-induced obese mice. These findings suggest that GGEx18 may be effective for preventing and treating NAFLD associated with visceral obesity.

Identification of differentially methylated region (DMR) networks associated with progression of nonalcoholic fatty liver disease

The progression of nonalcoholic fatty liver disease (NAFLD) is affected by epigenetics. We performed differentially methylated region (DMR) and co-methylation analyses to identify DMR networks associated with the progression of NAFLD. DMRs displaying differences in multiple consecutive differentially methylated CpGs between mild and advanced NAFLD were extracted. The average values of topological overlap measures for the CpG matrix combining two different DMRs were calculated and two DMR networks that strongly correlated with the stages of fibrosis were identified. The annotated genes of one network included genes involved in transcriptional regulation, cytoskeleton organization, and cellular proliferation. The annotated genes of the second network were primarily associated with metabolic pathways. The CpG methylation levels in these networks were strongly affected by age and fasting plasma glucose levels, which may be important co-regulatory factors. The methylation status of five DMRs in the second network was reversible following weight loss. Our results suggest that CpG methylation in DMR networks is regulated concomitantly via aging and hyperglycemia and plays important roles in hepatic metabolic dysfunction, fibrosis, and potential tumorigenesis, which occur during the progression of NAFLD. By controlling weight and blood glucose levels, the methylation of DMRs in the second network may be reduced.

Activation of apoptosis inhibitor of macrophage is a sensitive diagnostic marker for NASH-associated hepatocellular carcinoma

BACKGROUND

A diagnostic marker is needed enabling early and specific diagnosis of hepatocellular carcinoma (HCC) associated with non-alcoholic steatohepatitis (NASH). Our recent findings have indicated that circulating apoptosis inhibitor of macrophage (AIM), which usually associates with IgM pentamer in the blood, is activated by its dissociation from IgM. We investigated the serum levels of IgM-free AIM for AIM activation and its possible relationship with development of HCC in NASH.

METHODS

Serum levels of IgM-associated and IgM-free AIM were evaluated in patients with non-alcoholic fatty liver, NASH, and NASH-HCC using enzyme-linked immunosorbent assays and immunoblots. Liver biopsy specimens were graded and staged using Brunt's classification.

RESULTS

Forty-two patients with fatty liver, 141 with NASH, and 26 with NASH-HCC were evaluated. Patients with stage 4 or grade 3 NASH (with or without HCC) exhibited significantly higher levels of both IgM-free and total AIM than those with fatty liver, whereas the ratio of IgM-free-to-total AIM was equivalent in these groups. Among patients with the same fibrosis stage of NASH, those with HCC had significantly higher IgM-free but not total AIM levels, resulting in a proportional increase in the IgM-free/total AIM ratio. Analysis of the areas under the receiver operating characteristic curves indicated the high sensitivity of the IgM-free AIM for NASH-HCC.

CONCLUSIONS

Our observations suggest the activation of AIM in blood in the presence of NASH-HCC, with a significant increase in IgM-free AIM levels. IgM-free AIM serum levels appear to be a sensitive diagnostic marker for NASH-HCC.

Preperitoneal fat as a non-invasive marker of increased risk of severe non-alcoholic fatty liver disease in patients with type 2 diabetes

BACKGROUND AND AIM

Fat distribution may have prognostic value in the evaluation of non-alcoholic fatty liver disease. This study was conducted to evaluate associations of magnetic resonance imaging-measured abdominal fat areas with steatosis, steatohepatitis, and fibrosis, assessed histopathologically, in patients with type 2 diabetes.

METHODS

This prospective study included 66 patients with type 2 diabetes (12 males, 54 females, age 26-68 years), without chronic liver disease of other causes. Axial dual-echo magnetic resonance images were acquired. Visceral, subcutaneous, and preperitoneal fat areas were measured using Osirix software. Liver biopsy specimens were obtained from all patients and examined histopathologically to evaluate steatosis, steatohepatitis, and fibrosis. Linear (for steatosis) and logistic (for steatohepatitis and fibrosis) regression models were fitted for the outcomes. R2 was used as a measure of how much model variance the predictors explained and to compare different predictors of the same outcome.

RESULTS

Visceral and preperitoneal fat areas correlated well with histopathologically determined liver steatosis grade (both P = 0.004) and liver fibrosis (P = 0.008 and P = 0.037, respectively). All fat areas correlated well with steatohepatitis (P ≤ 0.002). Preperitoneal and visceral fat areas were the best predictors of steatohepatitis (R2 = 0.379) and fibrosis (R2 = 0.181), respectively.

CONCLUSIONS

Visceral fat area was the best predictor of fibrosis in patients with type 2 diabetes. Preperitoneal fat area was the best predictor of steatohepatitis and is a potential new non-invasive marker for use in the screening of these patients to detect more aggressive forms of non-alcoholic fatty liver disease.

Identification of the genomic region under epigenetic regulation during non-alcoholic fatty liver disease progression

AIM

The progression of non-alcoholic fatty liver disease (NAFLD) is affected by epigenetics. We undertook co-methylation and differentially methylated region (DMR) analyses to identify the genomic region that is under epigenetic regulation during NAFLD progression.

METHODS

We collected liver biopsy specimens from 60 Japanese patients with NAFLD and classified these into mild (fibrosis stages 0-2) or advanced (fibrosis stages 3-4) NAFLD. We carried out a genome-wide DNA methylation analysis and identified the differentially methylated CpGs between mild and advanced NAFLD. Differentially methylated regions with multiple consecutive differentially methylated CpGs between mild and advanced NAFLD were extracted.

RESULTS

Co-methylation analysis showed that individual differentially methylated CpG sites were clustered into three modules. The CpG sites clustered in one module were hypomethylated in advanced NAFLD and their annotated genes were enriched for "immune system" function. The CpG sites in another module were hypermethylated and their annotated genes were enriched for "mitochondria" or "lipid particle", and "lipid metabolism" or "oxidoreductase activity". Hypomethylated DMRs included tumorigenesis-related genes (FGFR2, PTGFRN, and ZBTB38), the expressions of which are upregulated in advanced NAFLD. Tumor suppressor MGMT had two DMRs and was downregulated. Conversely, FBLIM1 and CYR61, encoding proteins that reduce cell proliferation, showed hypomethylated DMRs and were upregulated. Expression of the antioxidant gene NQO1 was upregulated, with a hypomethylated DMR. The DMR containing cancer-related MIR21 was hypomethylated in advanced NAFLD.

CONCLUSIONS

Co-methylation and DMR analyses suggest that the NAFLD liver undergoes mitochondrial dysfunction, decreased lipid metabolism, and impaired oxidoreductase activity, and acquires tumorigenic potential at the epigenetic level.

Identification of core gene networks and hub genes associated with progression of non-alcoholic fatty liver disease by RNA sequencing

AIM

Non-alcoholic fatty liver disease (NAFLD) progresses because of the interaction between numerous genes. Thus, we carried out a weighted gene coexpression network analysis to identify core gene networks and key genes associated with NAFLD progression.

METHODS

We enrolled 39 patients with mild NAFLD (fibrosis stages 0-2) and 21 with advanced NAFLD (fibrosis stages 3-4). Total RNA was extracted from frozen liver biopsies, and sequenced to capture a large dynamic range of expression levels.

RESULTS

A total of 1777 genes differentially expressed between mild and advanced NAFLD (q-value <0.05) clustered into four modules. One module was enriched for genes that encode cell surface or extracellular matrix proteins, and are involved in cell adhesion, proliferation, and signaling. This module formed a scale-free network containing four hub genes (PAPLN, LBH, DPYSL3, and JAG1) overexpressed in advanced NAFLD. PAPLN is a component of the extracellular matrix, LBH and DPYSL3 are reported to be tumor suppressors, and JAG1 is tumorigenic. Another module formed a random network, and was enriched for genes that accumulate in the mitochondria. These genes were downregulated in advanced NAFLD, reflecting impaired mitochondrial function. However, the other two modules did not form unambiguous networks. KEGG analysis indicated that 71 differentially expressed genes were involved in "pathways in cancer". Strikingly, expression of half of all differentially expressed genes was inversely correlated with methylation of CpG sites (q-value <0.05). Among clinical parameters, serum type IV collagen 7 s was most strongly associated with the epigenetic status in NAFLD.

CONCLUSIONS

Newly identified core gene networks suggest that the NAFLD liver undergoes mitochondrial dysfunction and fibrosis, and acquires tumorigenic potential epigenetically. Our data provide novel insights into the pathology and etiology of NAFLD progression, and identify potential targets for diagnosis and treatment.

Plasma amino acid profile associated with fatty liver disease and co-occurrence of metabolic risk factors

Fatty liver disease (FLD) increases the risk of diabetes, cardiovascular disease, and steatohepatitis, which leads to fibrosis, cirrhosis, and hepatocellular carcinoma. Thus, the early detection of FLD is necessary. We aimed to find a quantitative and feasible model for discriminating the FLD, based on plasma free amino acid (PFAA) profiles. We constructed models of the relationship between PFAA levels in 2,000 generally healthy Japanese subjects and the diagnosis of FLD by abdominal ultrasound scan by multiple logistic regression analysis with variable selection. The performance of these models for FLD discrimination was validated using an independent data set of 2,160 subjects. The generated PFAA-based model was able to identify FLD patients. The area under the receiver operating characteristic curve for the model was 0.83, which was higher than those of other existing liver function-associated markers ranging from 0.53 to 0.80. The value of the linear discriminant in the model yielded the adjusted odds ratio (with 95% confidence intervals) for a 1 standard deviation increase of 2.63 (2.14–3.25) in the multiple logistic regression analysis with known liver function-associated covariates. Interestingly, the linear discriminant values were significantly associated with the progression of FLD, and patients with nonalcoholic steatohepatitis also exhibited higher values.

New trends on obesity and NAFLD in Asia

Traditionally, obesity and its related diseases have been considered a problem in Western countries. However, in the past two decades, urbanisation in many Asian countries has led to a sedentary lifestyle and overnutrition, setting the stage for the epidemic of obesity. This article reviews the epidemiological trend of obesity in Asia, with special emphasis on the emerging condition of non-alcoholic fatty liver disease (NAFLD). Currently, the population prevalence of NAFLD in Asia is around 25%, like many Western countries. While hepatocellular carcinoma and end-stage liver disease secondary to NAFLD remain uncommon, a rising trend has emerged. Around 8-19% of Asians with body mass indexes less than 25kg/m² are also found to have NAFLD, a condition often described as "lean" or "non-obese" NAFLD. Although this condition is generally less severe than that in more obese patients, steatohepatitis and fibrotic disease are well recognized. Central adiposity, insulin resistance and weight gain are major risk factors, and genetic predisposition, such as the PNPLA3 polymorphism appears to be more important in the development of NAFLD in the non-obese population. Lifestyle modification remains the cornerstone of management for obesity and NAFLD, but few patients can achieve adequate weight reduction and even fewer can maintain the weight in the long run. While pharmacological agents have entered phase III development for steatohepatitis, Asian patients are under-represented in most drug trials. Future studies should define the optimal management of obesity and NAFLD in Asia.

Lipotoxicity in Obesity: Benefit of Olive Oil

The clinical implication of Lipotoxicity in obesity derives primarily from its potential to progress to insulin resistance, endothelial dysfunction and atherosclerosis. Olive oil rich diet decrease accumulation of triglyceride in the liver, improved postprandial triglyceride levels, improve glucose and GLP-1 response in insulin resistant subjects, and up regulate GLUT-2 expression in the liver. The exact molecular mechanism is unknown but, decreasing NFkB activation, decreasing LDL oxidation and improving insulin resistance by less production of inflammatory cytokines (TNF-a, IL-6) and improvement of kinases JNK-mediated phosphorylation of IRS-1 are the principle mechanisms. The beneficial effect of the Mediterranean diet derived from monounsaturated fatty acids (MUFA), mainly from olive oil. In this review we document lipotoxicity in obesity and the benefit of olive oil.

S-1 induced hepatic steatosis in patients with pancreatic cancer: Retrospective analysis

AIM

To determine whether S-1 induces hepatic steatosis in patients being treated for pancreatic cancer.

METHODS

This retrospective study evaluated 22 patients who received oral S-1 as a first-line treatment for pancreatic cancer between January 2008 and July 2015 at the Ishikawa Prefectural Central Hospital. Patients underwent abdominal computed tomography (CT) scans before chemotherapy and within 3 mo from the start of treatment. CT numbers of the liver and spleen were measured before and after S-1 administration. Steatosis was diagnosed when the ratio of the CT number of the liver to that of the spleen (liver/spleen ratio) was < 0.9.

RESULTS

Median patient age was 68 years (range, 48-85 years), and median body mass index was 21 kg/m² (range, 18-27 kg/m²). Of the 22 patients, six (27%) regularly consumed alcohol, and five (23%) had liver metastases. The mean ratio of CT number of the liver to the spleen was significantly higher before administration of S-1 (1.27 vs 1.09, P = 0.012) compared with after. Of the 22 patients, five (23%) had hepatic steatosis and 17 (77%) did not. The pretreatment demographic and clinical characteristics of these two groups showed no significant differences. The relationship between liver/spleen ratio and alanine transaminase activity in these patients. A statistically significant inverse correlation was observed (r = -0.417, P < 0.027).

CONCLUSION

Of the 22 patients with pancreatic cancer, five (23%) experienced S-1 induced hepatic steatosis. Care should be taken during S-1 treatment of patients with pancreatic cancer.

Chronic hepatitis B, nonalcoholic steatohepatitis and physical fitness of military males: CHIEF study

AIM

To investigate the association of chronic hepatitis B and nonalcoholic steatohepatitis with physical fitness in a Taiwanese military male cohort.

METHODS

We made a cross-sectional examination of this association using 3669 young adult military males according to cardiorespiratory fitness and hospitalization events recorded in the Taiwan Armed Forces study. Cases of chronic hepatitis B (n = 121) were defined by personal history and positive detection of hepatitis B surface antigen. Cases of nonalcoholic steatohepatitis (n = 129) were defined by alanine transaminase level > 60 U/L, liver ultrasound finding of steatosis, and absence of viral hepatitis A, B or C infection. All other study participants were defined as unaffected (n = 3419). Physical fitness was evaluated by performance in 3000-m run, 2-min sit-ups, and 2-min push-ups exercises, with all the procedures standardized by a computerized scoring system. Multiple linear regression analysis was used to determine the relationship.

RESULTS

Chronic hepatitis B negatively correlated with 2-min push-up numbers (β = -2.49, P = 0.019) after adjusting for age, service specialty, body mass index, systolic and diastolic blood pressures, current cigarette smoking, alcohol intake status, serum hemoglobin, and average weekly exercise times. Nonalcoholic steatohepatitis was borderline positively correlated with 3000-m running time (β = 11.96, P = 0.084) and negatively correlated with 2-min sit-up numbers (β = -1.47, P = 0.040).

CONCLUSION

Chronic hepatitis B viral infection and nonalcoholic steatohepatitis affects different physical performances in young adult military males, and future study should determine the underlying mechanism.

Risk of Obesity-Related Cardiometabolic Complications in Special Populations: A Crisis in Asians

The prospect of a significant increase in global health-related costs associated with high cardiometabolic complications of obesity in Asians has encouraged more attention to be focused on the problem of growing obesity prevalence in these populations. Although these studies have shown that cardiometabolic complications occur more frequently and at a lower body mass index (BMI) in Asians than in European populations, the mechanisms involved have yet to be discovered. Ethnic/racial differences in body composition and fat distribution have been studied extensively. Although these studies have shown that increasing BMI is associated with larger increases in body fat content in Asians, growing evidence points to factors other than body fat content and fat distribution in determining a higher prevalence of cardiometabolic complications in these populations. Here, we provide support to our view that earlier onset of adipocyte maturation arrest/insulin resistance during weight gain could be a major factor in increasing the cardiometabolic risk of Asian populations at a lower BMI.

Increased Prevalence of Metabolic Risk Factors in Asian Americans With Hepatocellular Carcinoma

BACKGROUND

We used metabolic risk factors to estimate the prevalence and clinical significance of nonalcoholic fatty liver disease in Asian Americans with hepatocellular carcinoma (HCC).

METHODS

This is a retrospective cohort study of 824 consecutive Asian HCC patients at Stanford University Medical Center from 1998 to 2015. Patients were subdivided as: Chinese, other East Asian (Japanese and Korean), South East Asian (Vietnamese, Thai, and Laotian), Maritime South East Asian (MSEA: Malaysian, Indonesian, Filipino, and Singaporean), and South West Asian (Indian, Pakistani, and Middle Eastern). Metabolic risk factors studied were body mass index, hypertension, type II diabetes, and hyperlipidemia.

RESULTS

Most patients were male (76%) with mean age 63 years. Metabolic risk factors were highly prevalent on presentation and increased over time (P<0.001), as did the prevalence of cryptogenic HCC (P<0.004). Compared with other Asian subgroups, MSEAs had the highest body mass index (26.3) and higher rates of type II diabetes (44% vs. 23% to 35%, P=0.004), hypertension (59% vs. 38% to 55%, P=0.04), and cryptogenic HCC (15% vs. 4% to 10%, P=0.01). They were more likely to be symptomatic on presentation (44% vs. 32% to 58%, P=0.07), less likely to present within Milan criteria (34% vs. 35% to 63%, P<0.0001), and trended toward decreased 10-year survival rates compared with other ethnic subgroups (9% vs. 25% to 32%, P=0.07).

CONCLUSIONS

Metabolic risk factors were increasingly prevalent among Asian Americans with HCC. MSEAs, who had the highest incidence of these risk factors, had more advanced tumor stage and trended toward worse survival.

Classification of patients with non-alcoholic fatty liver disease using rapid immunoassay of serum type IV collagen compared with liver histology and other fibrosis markers

AIM

Non-alcoholic fatty liver disease (NAFLD) can progress to non-alcoholic fatty liver (NAFL) or non-alcoholic steatohepatitis (NASH). We investigated the association among serum type IV collagen level, liver histology, and other fibrosis markers in NAFLD progression.

METHODS

We evaluated 184 patients diagnosed with NAFLD following biopsy, including 89 males and 95 females with an average age of 52.6 and 62.6 years, respectively. Non-alcoholic fatty liver disease was classified as NAFL or NASH using Matteoni's classification, and the grade and stage of NASH were assessed using Brunt's classification. Serum type IV collagen was measured by a rapid and sensitive latex particle-enhanced turbidimetric immunoassay.

RESULTS

Forty-two patients with NAFL and 142 patients with NASH were included in this study. Compared with patients with NAFL, patients with NASH showed more significant liver function disorder and increased expression of fibrosis markers including type IV collagen, collagen 7S, Mac2-binding protein (M2BP), and hyaluronic acid (HA). Expression of type IV collagen and collagen 7S, but not M2BP and HA, was more significantly elevated in patients with stage 1 NASH than in patients with NAFL, indicating that type IV collagen and collagen 7S may be better discriminators of NASH and NAFL than M2BP and HA at an early stage of fibrosis. When patients were stratified by NAFLD activity score, type IV collagen and collagen 7S were significantly elevated as NAFLD activity score progressed, whereas M2BP and HA expression were not significantly elevated.

CONCLUSION

Type IV collagen may be a useful measure of NASH severity as latex particle-enhanced turbidimetric immunoassay-based rapid type IV collagen assay can be carried out routinely.

Altered Gut Microbiota Composition and Immune Response in Experimental Steatohepatitis Mouse Models

BACKGROUND

Although several types of diet have been used in experimental steatohepatitis models, comparison of gut microbiota and immunological alterations in the gut among diets has not yet been performed.

AIM

We attempted to clarify the difference in the gut environment between mice administrated several experimental diets.

METHODS

Male wild-type mice were fed a high-fat (HF) diet, a choline-deficient amino acid-defined (CDAA) diet, and a methionine-choline-deficient (MCD) diet for 8 weeks. We compared the severity of steatohepatitis, the composition of gut microbiota, and the intestinal expression of interleukin (IL)-17, an immune modulator.

RESULTS

Steatohepatitis was most severe in the mice fed the CDAA diet, followed by the MCD diet, and the HF diet. Analysis of gut microbiota showed that the composition of the Firmicutes phylum differed markedly at order level between the mice fed the CDAA and HF diet. The CDAA diet increased the abundance of Clostridiales, while the HF diet increased that of lactate-producing bacteria. In addition, the CDAA diet decreased the abundance of lactate-producing bacteria and antiinflammatory bacterium Parabacteroides goldsteinii in the phylum Bacteroidetes. In CDAA-fed mice, IL-17 levels were increased in ileum as well as portal vein. In addition, the CDAA diet also elevated hepatic expression of chemokines, downstream targets of IL-17.

CONCLUSIONS

The composition of gut microbiota and IL-17 expression varied considerably between mice administrated different experimental diets to induce steatohepatitis.

Mitochondrial carnitine palmitoyl transferase-II inactivity aggravates lipid accumulation in rat hepatocarcinogenesis

AIM

To investigate the dynamic alteration of mitochondrial carnitine palmitoyl transferase II (CPT-II) expression during malignant transformation of rat hepatocytes.

METHODS

Sprague-Dawley male rats were fed with normal, high fat (HF), and HF containing 2-fluorenylacetamide (2-FAA) diet, respectively. According to the Hematoxylin and Eosin staining of livers, rats were divided into control, fatty liver, degeneration, precancerous, and cancerous groups. Liver lipids were dyed with Oil Red O, CPT-II alterations were analyzed by immunohistochemistry, and compared with CPT-II specific concentration (μg/mg protein). Levels of total cholesterol (Tch), triglyceride (TG), and amino-transferases [alanine aminotransferase (ALT), aspartate aminotransferase (AST)] were determined by the routine methods.

RESULTS

After intake of HF and/or HF+2-FAA diets, the rat livers showed mass lipid accumulation. The lipid level in the control group was significantly lower than that in other groups. The changes of serum TG and Tch levels were abnormally increasing, 2-3 times more than those in the controls (P < 0.05). During the rat liver morphological changes from normal to cancer development process with hepatocyte injury, serum AST and ALT levels were significantly higher (4-8 times, P < 0.05) than those in the control group. The specific concentration of CPT-II in liver tissues progressively decreased during hepatocyte malignant transformation, with the lowest CPT-II levels in the cancer group than in any of the other groups (P < 0.05).

CONCLUSION

Low CPT-II expression might lead to abnormal hepatic lipid accumulation, which should promote the malignant transformation of hepatocytes.

Prevalence of chronic liver disease and cirrhosis by underlying cause in understudied ethnic groups: The multiethnic cohort

Chronic liver disease (CLD) and cirrhosis are major sources of morbidity and mortality in the United States. Little is known about the epidemiology of these two diseases in ethnic minority populations in the United States. We examined the prevalence of CLD and cirrhosis by underlying etiologies among African Americans, Native Hawaiians, Japanese Americans, Latinos, and whites in the Multiethnic Cohort. CLD and cirrhosis cases were identified using Medicare claims between 1999 and 2012 among the fee-for-service participants (n = 106,458). We used International Classification of Diseases Ninth Revision codes, body mass index, history of diabetes mellitus, and alcohol consumption from questionnaires to identify underlying etiologies. A total of 5,783 CLD (3,575 CLD without cirrhosis and 2,208 cirrhosis) cases were identified. The prevalence of CLD ranged from 3.9% in African Americans and Native Hawaiians to 4.1% in whites, 6.7% in Latinos, and 6.9% in Japanese. Nonalcoholic fatty liver disease (NAFLD) was the most common cause of CLD in all ethnic groups combined (52%), followed by alcoholic liver disease (21%). NAFLD was the most common cause of cirrhosis in the entire cohort. By ethnicity, NAFLD was the most common cause of cirrhosis in Japanese Americans, Native Hawaiians, and Latinos, accounting for 32% of cases. Alcoholic liver disease was the most common cause of cirrhosis in whites (38.2%), while hepatitis C virus was the most common cause in African Americans (29.8%).

CONCLUSIONS

We showed racial/ethnic variations in the prevalence of CLD and cirrhosis by underlying etiology; NAFLD was the most common cause of CLD and cirrhosis in the entire cohort, and the high prevalence of NAFLD among Japanese Americans and Native Hawaiians is a novel finding, warranting further studies to elucidate the causes. (Hepatology 2016;64:1969-1977).

A diet-induced Sprague-Dawley rat model of nonalcoholic steatohepatitis-related cirrhosis

Certain modified diets containing saturated fatty acids, cholesterol or fructose lead to the development of nonalcoholic steatohepatitis (NASH)-related fibrosis in rodents; however, progression to cirrhosis is rare. Experimental liver cirrhosis models have relied on genetic manipulation or administration of hepatotoxins. This study aimed to establish a reliable dietary model of NASH-related cirrhosis in a relatively short period. Male Sprague-Dawley rats (9 weeks of age) were randomly assigned to normal, high-fat (HF), or two types (1.25% or 2.5% cholesterol) of high-fat and high-cholesterol (HFC) diets for 18 weeks. All HFC diets contained 2% cholic acid by weight. Histopathological analysis revealed that the HFC diets induced obvious hepatic steatosis, inflammation with hepatocyte ballooning and advanced fibrosis (stage 3-4) in all 12 rats at 27 weeks of age. In contrast, all five rats given the HF diet developed mild steatosis and inflammation without fibrosis. The amount of cholesterol in the liver and hepatocellular mitochondrial and microsomal fractions was significantly higher in rats fed the HFC diets than the normal or HF diets. The HFC diets significantly suppressed mRNA levels of microsomal triglyceride transfer protein, adenosine triphosphate binding cassette transporter G5, bile acid CoA: amino acid N-acyltransferase and bile salt export pump, as well as the enzymatic activity of carnitine palmitoyltransferase in the liver. In conclusion, the HFC diets induced liver cirrhosis in conjunction with hepatic features of NASH in Sprague-Dawley rats within 18 weeks, and altered gene expression and enzyme activity to accumulate lipid and bile acid in the liver.

Ultrasonography screening for hepatocellular carcinoma in Japanese patients with diabetes mellitus

BACKGROUND

Effective surveillance for hepatocellular carcinoma (HCC) in diabetes mellitus (DM) has not been established. We elucidated the risk factors for HCC in DM patients.

METHODS

From 2000 to 2014, 80 patients diagnosed with HCC for the first time who had concomittant DM but no other etiology of liver disease were enrolled as the DM-HCC group. From 2005 October to 2014, after introduction of the abdominal ultrasonography (US) report database, 2083 DM patients with no viral hepatitis, no known autoimmune hepatic diseases, and/or no evidence of alcohol abuse (>60 g/day) were enrolled as the DM-US group. Findings from the first US screening were evaluated. "Elderly" patients were defined as those aged >65 years. Clinical features of DM-HCC patients were evaluated and compared with those of DM-US patients.

RESULTS

In the DM-HCC group (54 men, 26 women), the mean (± SD age was 74.1 ± 8.5 years, and mean HbA1c and fibrosis-4 (FIB-4) index were 7.3 ± 1.3% and 4.50 ± 3.42, respectively. Mean tumor diameter was 5.7 ± 3.5 cm, there were 63/13/2/2 patients classified as Child-Pugh A/B/C/unknown, and 56/24 were single/multiple lesions. In the DM-US group, HCC was detected in three patients (0.14%; 0.3% of those classified as elderly). The mean age and FIB-4 index of these three patients (one man, two women) were 75.6 years (range 67-92 years) and 4.84 (range 2.87-6.98), respectively. Mean tumor diamter was 7.6 cm and there were one and two single and multiple lesions, respectively. In elderly DM-US patients with a high FIB-4 index (≥4), the rate of HCC detection was 5.0%.

CONCLUSIONS

Being elderly and having a high FIB-4 index are characteristic features of DM-HCC. Similar characteristics were noted for patients with HCC in the DM-US group. HCC surveillance with US is recommended for DM patients, especially those who are elderly (≥65 years) and have a high FIB-4 index.

Impact of physical activity on nonalcoholic steatohepatitis in people with nonalcoholic simple fatty liver: A prospective cohort study

Preventing nonalcoholic simple fatty liver (NASFL) from progressing to nonalcoholic steatohepatitis (NASH) is a key to avoiding cirrhosis. Physical activity (PA) may help manage fatty liver; however, there is a lack of prospective studies showing an association between PA and NASH. Our current prospective study investigated whether PA prevents NASFL from progressing to NASH. Study data were obtained from the health check-up program of Meiji Yasuda Shinjuku Medical Center in Tokyo, Japan. From a baseline survey between 2005 and 2007, 1149 people with NASFL met eligibility criteria including low alcohol consumption. We followed participants until 2014 assessing liver status via ultrasound and liver enzyme levels, including alanine aminotransferase (ALT) and aspartate aminotransferase (AST). We classified participants with fatty liver and higher levels of either ALT or AST as having NASH. Through a self-reported questionnaire, we classified PA into three intensities: moderate low-intensity PA (MLPA, 3-5 METs), moderate high-intensity PA (MHPA, 5-7 METs), and vigorous-intensity PA (VPA, ≥7 METs). During a mean follow-up of 4.2years (4804person-years), 318 of the 1149 participants (27.7%) progressed from NASFL to NASH. A multivariate-adjusted Cox model showed a significant preventive effect of VPA on progression to NASH (HR=0.55, 95% CI=0.32-0.94) and no significant associations between MLPA (HR=1.01, 95% CI=0.79-1.30) or MHPA (HR=0.97, 95% CI=0.66-1.42) and progression to NASH. Only VPA prevented NASFL from progressing to NASH; MLPA and MHPA had no preventive effect on NASH. Higher intensity PA may be needed to manage NASH.

Development of a novel mouse model of hepatocellular carcinoma with nonalcoholic steatohepatitis using a high-fat, choline-deficient diet and intraperitoneal injection of diethylnitrosamine

Background

The incidence of hepatocellular carcinoma with nonalcoholic steatohepatitis is increasing, and its clinicopathological features are well established. Several animal models of nonalcoholic steatohepatitis have been developed to facilitate its study; however, few fully recapitulate all its clinical features, which include insulin resistance, inflammation, fibrosis, and carcinogenesis. Moreover, these models require a relatively long time to produce hepatocellular carcinoma reliably. The aim of this study was to develop a mouse model of hepatocellular carcinoma with nonalcoholic steatohepatitis that develops quickly and reflects all clinically relevant features.

Methods

Three-week-old C57BL/6J male mice were fed either a standard diet (MF) or a choline-deficient, high-fat diet (HFCD). The mice in the MF + diethylnitrosamine (DEN) and HFCD + DEN groups received a one-time intraperitoneal injection of DEN at the start of the respective feeding protocols.

Results

The mice in the HFCD and HFCD + DEN groups developed obesity early in the experiment and insulin resistance after 12 weeks. Triglyceride levels peaked at 8 weeks for all four groups and decreased thereafter. Alanine aminotransferase levels increased every 4 weeks, with the HFCD and HFCD + DEN groups showing remarkably high levels; the HFCD + DEN group presented the highest incidence of nonalcoholic steatohepatitis. The levels of fibrosis and steatosis varied, but they tended to increase every 4 weeks in the HFCD and HFCD + DEN groups. Computed tomography scans indicated that all the HFCD + DEN mice developed hepatic tumors from 20 weeks, some of which were glutamine synthetase-positive.

Conclusions

The nonalcoholic steatohepatitis-hepatocellular carcinoma model we describe here is simple to establish, results in rapid tumor formation, and recapitulates most of the key features of nonalcoholic steatohepatitis. It could therefore facilitate further studies of the development, oncogenic potential, diagnosis, and treatment of this condition.

Electronic supplementary material

The online version of this article (doi:10.1186/s12876-016-0477-5) contains supplementary material, which is available to authorized users.

Influence of the rs738409 polymorphism in patatin-like phospholipase 3 on the treatment efficacy of non-alcoholic fatty liver disease with type 2 diabetes mellitus

AIM

A genome-wide association study revealed that the single nucleotide polymorphism (SNP) rs738409 in the patatin-like phospholipase 3 gene (PNPLA3) was strongly associated with non-alcoholic fatty liver disease (NAFLD). Recent pilot studies investigated the effects of dipeptidyl peptidase-4 inhibitors on liver function and glucose metabolism in NAFLD with type 2 diabetes mellitus (DM). We herein evaluated the efficacy of alogliptin in NAFLD patients with type 2 DM as well as the relationship between genotypes at rs738409 in PNPLA3 and treatment efficacy.

METHODS

Forty-one biopsy-proven NAFLD patients with type 2 DM treated with 25 mg/day alogliptin were retrospectively enrolled. SNP rs738409 in PNPLA3 was present in all patients. Clinical data were measured before and after the treatment.

RESULTS

Average hemoglobin A1c (HbA1c) levels mostly remained unchanged. Moreover, significant changes were not noted in the levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) during the follow-up period. A positive correlation was observed between improvements in HbA1c (ΔHbA1c) levels and changes in AST (ΔAST) and ALT (ΔALT) levels (r = 0.325 and 0.439, respectively). Patients with the risk allele (G-allele) showed more positive correlation between ΔHbA1c and changes in transaminase. Furthermore, improvements in the levels of total cholesterol, triglycerides and hyaluronic acid were significantly greater in G-allele patients in the weight loss group.

CONCLUSION

The treatment of NAFLD with type 2 DM with alogliptin contributed to the amelioration of NAFLD. Our results suggested that differences in the PNPLA3 risk allele affected the therapeutic effects of this treatment.

Targeted-bisulfite sequence analysis of the methylation of CpG islands in genes encoding PNPLA3, SAMM50, and PARVB of patients with non-alcoholic fatty liver disease

BACKGROUND & AIMS

The pathogenesis of non-alcoholic fatty liver disease (NAFLD) is affected by epigenetic factors as well as by genetic variation.

METHODS

We performed targeted-bisulfite sequencing to determine the levels of DNA methylation of 4 CpG islands (CpG99, CpG71, CpG26, and CpG101) in the regulatory regions of PNPLA3, SAMM50, PARVB variant 1, and PARVB variant 2, respectively. We compared the levels of methylation of DNA in the livers of the first and second sets of patients with mild (fibrosis stages 0 and 1) or advanced (fibrosis stages 2 to 4) NAFLD and in those of patients with mild (F0 to F2) or advanced (F3 and F4) chronic hepatitis C infection. The hepatic mRNA levels of PNPLA3, SAMM50, and PARVB were measured using qPCR.

RESULTS

CpG26, which resides in the regulatory region of PARVB variant 1, was markedly hypomethylated in the livers of patients with advanced NAFLD. Conversely, CpG99 in the regulatory region of PNPLA3 was substantially hypermethylated in these patients. These differences in DNA methylation were replicated in a second set of patients with NAFLD or chronic hepatitis C. PNPLA3 mRNA levels in the liver of the same section of a biopsy specimen used for genomic DNA preparation were lower in patients with advanced NAFLD compared with those with mild NAFLD and correlated inversely with CpG99 methylation in liver DNA. Moreover, the levels of CpG99 methylation and PNPLA3 mRNA were affected by the rs738409 genotype.

CONCLUSIONS

Hypomethylation of CpG26 and hypermethylation of CpG99 may contribute to the severity of fibrosis in patients with NAFLD or chronic hepatitis C infection.

Suppression of silent information regulator 1 activity in noncancerous tissues of hepatocellular carcinoma: Possible association with non-B non-C hepatitis pathogenesis

Silent information regulator 1 (SIRT1) is a nicotinamide adenine dinucleotide (NAD⁺)-dependent protein deacetylase. In mice, mSirt1 deficiency causes the onset of fatty liver via regulation of the hepatic nutrient metabolism pathway. In this study, we demonstrate SIRT1 expression, activity and NAD⁺ regulation using noncancerous liver tissue specimens from hepatocellular carcinoma patients with non-B non-C (NBNC) hepatitis. SIRT1 expression levels were higher in NBNC patients than in healthy donors, while SIRT1 histone H3K9 deacetylation activity was suppressed in NBNC patients. In the liver of hepatitis patients, decreased NAD⁺ amounts and its regulatory enzyme nicotinamide phosphoribosyltransferase expression levels were observed, and this led to inhibition of SIRT1 activity. SIRT1 expression was associated with HIF1 protein accumulation in both the NBNC liver and liver cancer cell lines. These results may indicate that the NBNC hepatitis liver is exposed to hypoxic conditions. In HepG2 cells, hypoxia induced inflammatory chemokines, such as CXCL10 and MCP-1. These inductions were suppressed in rich NAD⁺ condition, and by SIRT1 activator treatment. In conclusion, hepatic SIRT1 activity was repressed in NBNC patients, and normalization of NAD⁺ amounts and activation of SIRT1 could improve the inflammatory condition in the liver of NBNC hepatitis patients.

Usefulness of ultrasonographic estimation of preperitoneal and subcutaneous fat thickness in the diagnosis of nonalcoholic fatty liver disease in diabetic patients

PURPOSE

Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) have been regarded as the hepatic manifestation of metabolic syndrome. Abdominal wall fat index (AFI), defined as the ratio of preperitoneal and subcutaneous fat thickness in the abdomen estimated by ultrasonography (US), has been shown to be useful in screening for disorders related to metabolic syndrome. We investigated the relation between AFI and NAFLD/NASH in diabetic patients.

METHODS

The degree of fat accumulation in the liver and the thickness of preperitoneal and subcutaneous fat were determined by US in 340 diabetic patients. An NAFLD fibrosis score (NAFLD-FS) was used to assess the advancement of hepatic fibrosis in NAFLD patients.

RESULTS

Of all 340 subjects, 209 (61 %) were diagnosed with NAFLD by US. AFI of NAFLD subjects was significantly higher than that of non-NAFLD subjects. Of the 209 subjects with NAFLD, 31 (15 %) were shown to have advanced NASH fibrosis according to NAFLD-FS. Multivariate analysis identified AFI as a significant predictor of advanced fibrosis.

CONCLUSION

AFI easily obtained by US was significantly related to the presence of NAFLD and/or advanced hepatic fibrosis in diabetic patients.

Clinical features of hepatocellular carcinoma associated with nonalcoholic fatty liver disease: a review of human studies

Most cases of hepatocellular carcinoma (HCC) in Japan develop in the background of chronic liver disease caused by hepatitis C virus (HCV). Recently, however, HCV-associated HCC has been shown to be decreasing, while non-B and non-C HCC (NBNC-HCC), which is negative for HCV and hepatitis B virus infection, has increased. The main cause of NBNC-HCC is alcoholic liver disease, but the recent increase of NBNC-HCC is thought to be due to an increase in patients with nonalcoholic fatty liver disease (NAFLD). Approximately 10% of NAFLD cases involve nonalcoholic steatohepatitis (NASH), and NASH can progress to liver cirrhosis and its associated complications such as HCC. There are no accurate data on the percentage of NASH-related HCC among all-cause HCC in Japan, because no large-scale investigation has been performed. However, the rate is thought to be about 3% of overall HCC, which is lower than that in the United States. The incidence of HCC in patients with NASH-related cirrhosis is thought to be 2% per year, which is lower than that in HCV-related cirrhosis. Risks for NASH-related HCC include advanced hepatic fibrosis, older age, and being male. NAFLD that includes NASH is associated with metabolic syndrome, which includes obesity and diabetes, and metabolic syndrome is a risk factor for HCC. Genetic factors and dietary patterns may also be related to NASH-related HCC. Thus, regular HCC surveillance, as performed for patients with viral chronic liver disease, is required for patients with NAFLD, and diagnostic markers are required for simple, rapid and specific detection of NASH-related HCC.

Non-invasive assessment of liver steatosis in non-alcoholic fatty liver disease

AIM

The diagnosis of non-alcoholic fatty liver disease (NAFLD) is based on the histological findings. Further, there may be interobserver differences. Liver to spleen (L/S) ratio on computed tomography (CT) is employed to detect or even quantify the fat content of the liver. The objective of this study was to accurately diagnose fatty liver by evaluating the relationship between L/S ratio and histological findings.

METHODS

Sixty-seven biopsy-proven NAFLD patients were enrolled. L/S ratio on CT was calculated. The area of steatosis in liver specimens was measured by BIOREVO BZ-9000 microscope, and the percentage of steatosis was calculated using Dynamic cell count BZ-H1C software.

RESULTS

Steatotic grade assessed by pathologist was significantly correlated with the percentage of steatosis and L/S ratio. Factors associated with steatosis were L/S ratio, aspartate aminotransferase and Homeostasis Model of Assessment - Insulin Resistance as determined by multivariate analysis. L/S ratios were: S0, 1.16 ± 0.20 (mean ± standard deviation); S1, 0.88 ± 0.28; S2, 0.76 ± 0.20; and S3, 0.40 ± 0.18, respectively. The optimal cut-off value of L/S ratio to exclude steatosis was 1.1, and the area under the receiver-operator curve for the diagnosis of steatosis was 0.886.

CONCLUSION

Our study suggests that while 0% of steatosis showed 1.296 L/S ratio, the cut-off value of L/S ratio would be 1.1 at least to exclude clinically important liver steatosis.

Living donor liver transplantation for non-alcoholic steatohepatitis: A single center experience

AIM

The number of patients referred for liver transplantation (LT) with non-alcoholic steatohepatitis (NASH) continues to increase, but information about living donor liver transplantation (LDLT) for NASH is scarce. We conducted this study to document the details of LDLT for NASH in a Japanese LT center.

METHODS

Among all LDLT recipients in our institution from March 1996 to March 2013 (n = 425), we identified seven patients that underwent LDLT for NASH.

RESULTS

Of all the seven recipients, most of the patients (86%) were obese. The median follow-up period post-LDLT was 5.3 years. All were alive at the last follow-up. Recurrent NASH was detected in one patient (14%), and no recurrent hepatic steatosis was detected among the remaining six recipients on prospectively performed ultrasonography. No significant comorbidities were observed following donor surgery among the respective living donors during the follow-up period. We also retrospectively reviewed 22 patients with NASH-related end-stage liver disease (ESLD) who were evaluated but rejected for LDLT during the same period. The reasons for rejection for LDLT were presumably associated with the nature of NAFLD/NASH in either potential recipients or donors.

CONCLUSION

The post-transplant outcome of LDLT for NASH-related ESLD in our institution was feasible, although the sample size was small. Further studies in a larger patient cohort are warranted to investigate the long-term outcome of LDLT for NASH, both for recipients and living donors.

Elevation of Serum Levels of Advanced Glycation End Products in Patients With Non-B or Non-C Hepatocellular Carcinoma

BACKGROUND

The prevalence of non-B or non-C hepatocellular carcinoma (NBNC-HCC) has been increasing all over the world. Advanced glycation end products (AGE) play a role in the pathogenesis of alcoholic liver injury or nonalcoholic steatohepatitis (NASH).

METHODS

We examined here whether serum levels of AGE were elevated in NBNC-HCC patients compared with NASH subjects without HCC and investigated which anthropometric and clinical variables were independent determinants of AGE.

RESULTS

Ninety NBNC-HCC, 56 NASH, and 27 control subjects underwent a complete history and physical examination, determination of blood chemistries, including AGE levels. Serum levels of AGE were significantly higher in NBNC-HCC patients compared with NASH and control subjects [9.1 ± 2.7, 5.2 ± 1.7, 3.5 ± 1.2 (U/ml), respectively, P < 0.05]. Univariate analysis showed that AGE levels were associated with male (P < 0.05), age (P < 0.01), aspartate aminotransferase (P < 0.05), γ-glutamyl transpeptidase (GGT) (P < 0.01), HDL-cholesterol (inversely, P < 0.01), fasting plasma glucose (P < 0.01), and HbA1c (P < 0.05). By the use of multiple stepwise regression analysis, age, GGT, and HDL-cholesterol (inversely) remained significant and were independently related to AGE levels (R(2) = 0.406).

CONCLUSION

The present results suggest that AGE might be involved in the pathogenesis of NBNC-HCC, thereby being a biomarker that could discriminate NBNC-HCC from NASH.

Relationship between serum uric acid levels and hepatic steatosis in non-obese postmenopausal women

OBJECTIVE

Serum uric acid levels have been reported to be associated with non-alcoholic fatty liver disease (NAFLD). However, very few studies specifically examining the relationship between serum uric acid (SUA) levels and NAFLD in postmenopausal women have been reported in China, especially in postmenopausal women with normal body mass index (BMI) in whom NAFLD is not uncommon.

METHODS

A cross-sectional study was employed of 528 Chinese normal-BMI postmenopausal women (aged 41-79 years) who participated in annual health check-ups. NAFLD is defined as a hepatic steatosis observed on liver ultrasonography in the absence of a second cause. Of all the participants, 121 women were diagnosed with hepatic steatosis (NAFLD group) and the others were without (non-NAFLD group). SUA quartiles were defined as follows: Q1, < 3.8 mg/dl; Q2, 3.8-4.4 mg/dl; Q3, 4.5-5.0 mg/dl; Q4, 5.1-6.0 mg/dl. Stepwise multivariable regression analysis was used to assess the relationships between SUA level and other variables. The association between SUA quartiles and hepatic steatosis was assessed using binary logistic regression.

RESULTS

Compared to the non-NAFLD group, the mean level of SUA was significantly higher in the NAFLD group (p < 0.01). The adjusted odds ratio (95% confidence interval) for the presence of hepatic steatosis in the highest SUA quartile vs. the lowest quartile was 2.774 (1.396-5.513) for all women (p < 0.01) after adjusting for the factors which were independently associated with uric acid level including waist circumference, high blood pressure, blood urea nitrogen, creatinine, γ-glutamyltransferase, and triglycerides. Most estimates changed little after further adjustment for age, metabolic syndrome, drinking status, and smoking status. The presence of hepatic steatosis significantly increased in the third and fourth quartiles of SUA. The prevalence of hepatic steatosis increased gradually with an increasing SUA quartile (p for trend < 0.01).

CONCLUSION

Higher SUA levels even within the normal range are positively and independently associated with the presence of hepatic steatosis in Chinese postmenopausal women with normal BMI.

Physical activity and risk of fatty liver in people with different levels of alcohol consumption: a prospective cohort study

OBJECTIVE

To investigate whether physical activity affects the future incidence of fatty liver in people with never-moderate and heavy alcohol consumption.

DESIGN

Prospective cohort study.

SETTING

Health check-up programme at Meiji Yasuda Shinjuku Medical Center in Shinjuku Ward, Tokyo, Japan.

POPULATION

A total of 10,146 people aged 18 years or older without fatty liver enrolled through baseline surveys conducted from 2005 to 2007. They were grouped into never-moderate alcohol drinkers (n=7803) and heavy alcohol drinkers (n=2343) and followed until 2013.

MAIN OUTCOME MEASURE

Incident fatty liver diagnosed by ultrasound.

RESULTS

During a mean follow-up of 4.4 years (34,648 person-years), 1255 never-moderate alcohol drinkers developed fatty liver; 520 heavy alcohol drinkers developed fatty liver during a mean follow-up of 4.1 years (9596 person-years). For never-moderate alcohol drinkers, engaging in >3×/week of low-intensity (HR=0.82, 95% CI 0.71 to 0.96) and moderate-intensity (HR=0.56, 95% CI 0.39 to 0.81) physical activity significantly reduced incident fatty liver compared with those who engaged in physical activity <1×/week. For vigorous-intensity physical activity, frequencies of 2×/week (HR=0.57, 95% CI 0.38 to 0.86) and >3×/week (HR=0.55, 95% CI 0.38 to 0.79) were significantly associated with lower risk of incident fatty liver. In propensity-adjusted models, these significant associations still remained. By contrast, in heavy alcohol drinkers, there were no significant associations between the type or frequency of physical activity and incident fatty liver.

CONCLUSIONS

Physical activity had an independent protective effect on incident fatty liver only in the never-moderate alcohol drinkers, and the preventive effect increased with higher frequencies and intensities of physical activity.