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Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. Nonalcoholic steatohepatitis (NASH) is an advanced form of NAFLD can progress to liver cirrhosis and hepatocellular carcinoma (HCC). Recently, the prognosis of NAFLD/NASH has been reported to be dependent on liver fibrosis degree. Liver biopsy remains the gold standard, but it has several issues that must be addressed, including its invasiveness, cost, and inter-observer diagnosis variability. To solve these issues, a variety of noninvasive tests (NITs) have been in development for the assessment of NAFLD progression, including blood biomarkers and imaging methods, although the use of NITs varies around the world. The aim of the Japan NASH NIT (JANIT) Forum organized in 2020 is to advance the development of various NITs to assess disease severity and/or response to treatment in NAFLD patients from a scientific perspective through multi-stakeholder dialogue with open innovation, including clinicians with expertise in NAFLD/NASH, companies that develop medical devices and biomarkers, and professionals in the pharmaceutical industry. In addition to conventional NITs, artificial intelligence will soon be deployed in many areas of the NAFLD landscape. To discuss the characteristics of each NIT, we conducted a SWOT (strengths, weaknesses, opportunities, and threats) analysis in this study with the 36 JANIT Forum members (16 physicians and 20 company representatives). Based on this SWOT analysis, the JANIT Forum identified currently available NITs able to accurately select NAFLD patients at high risk of NASH for HCC surveillance/therapeutic intervention and evaluate the effectiveness of therapeutic interventions.

The FIB4 index is clinically useful, but because its formula includes age, the appropriate cutoff point may differ by age group. Here, new FIB4 index cutoff points were validated using cohort data from 14 hepatology centers in Japan. The FIB4 index was determined in biopsy-confirmed NAFLD patients (n = 1050) who were divided into four groups: ≤ 49, 50–59, 60–69, and ≥ 70 years. ROC analysis predicted advanced fibrosis in each age group; low and high cutoff points were defined by a sensitivity and specificity of 90%. The new and conventional cutoffs were compared for detecting advanced fibrosis. The modified low and high cutoff points were 1.05 and 1.21 in ≤ 49 years, 1.24 and 1.96 in 50–59 years, 1.88 and 3.24 in 60–69 years, and 1.95 and 4.56 in ≥ 70 years. In ≥ 60 years, the false-negative rate was increased using the modified high cutoff point, and the high cutoff point was better with the conventional cutoff point. The new proposed low and high cutoff points are 1.05 and 1.21 in ≤ 49 years, 1.24 and 1.96 in 50–59 years, 1.88 and 2.67 in 60–69 years, and 1.95 and 2.67 in ≥ 70 years; these cutoff points improved the accuracy of advanced fibrosis diagnosis. FIB4 index cutoff points for predicting advanced fibrosis in NAFLD increased with age. Cutoff points modified by age improved the diagnostic accuracy of estimations of advanced liver fibrosis using the FIB4 index.

The risk factors in the progression of nonalcoholic fatty liver disease (NAFLD) have not been fully clarified. Porphyromonas gingivalis (P.g) has been considered to be a confounding risk factor for systemic diseases. We aimed to evaluate the effect of P.g infection on risk of progression to NASH. (1) Serum IgG antibody titers against P.g fimbriae (fimA) in 200 biopsy-proven NAFLD patients were measured by ELISA and compared with histological findings. (2) C57BL/6J mice were fed a control diet (CD) or high-fat diet (HFD) with or without P.g-odontogenic infection and analyzed histologically. Mouse livers were analyzed using CE–TOFMS and LC–TOFMS. (1) A significant correlation between fibrosis progression and antibody titers against P.g possessing fimA type 4 was identified (P = 0.0081). Multivariate analysis identified older age and type 4 P.g-positivity as risk factors for advanced fibrosis. (2) Fibrosis and steatosis were more severe in HFD P.g(+) mice compared with HFD P.g(−) mice. In metabolome analysis, fatty acid metabolism was significantly disrupted with HFD in P.g-infected mouse livers. Monounsaturated/saturated fatty acid ratios were significantly higher in the HFD P.g(+) group than in the HFD P.g(−) group (P

The coauthor Masashi Yoneda's affiliation has been incorrectly published in the original publication of the article. The correct affiliation is provided in this correction.

In Japan, the prevalence of hepatocellular carcinoma (HCC) associated with nonviral liver disease, especially with nonalcoholic fatty liver disease (NAFLD-HCC) and alcoholic liver disease (ALD-HCC), has been increasing. Clarification of the clinical features of NAFLD-HCC and ALD-HCC is needed. We performed a large retrospective multicenter survey to clarify the clinical course of these two types of HCC. Clinical characteristics, survival, and recurrence were examined in 532 patients with ALD-HCC and 209 patients with NAFLD-HCC who were diagnosed between January 2000 and December 2013. The ALD-HCC patients were predominantly male and were younger than the patients with NAFLD-HCC. Lifestyle-related diseases were significantly more common in the NAFLD-HCC group, but the prevalence of cirrhosis was significantly higher in the ALD-HCC group. The histological diagnosis of NAFLD-HCC showed a gender difference (F4; 72.7 % in the females vs. 37.6 % in the males). The characteristic features of HCC including histology, survival rate, and recurrence rate were quite similar in the NAFLD-HCC and ALD-HCC groups: 5-year survival rates 49.1 vs. 43.7 %; 5-year recurrence rates 69.6 vs. 65.4 %, respectively. However, the risk factors for recurrence differed between the two groups: des-gamma-carboxy prothrombin was a risk factor in NAFLD-HCC and α-fetoprotein was a risk factor in ALD-HCC. Although the characteristic features underlying these two diseases are different, the two HCC groups showed a similar clinical course. The recurrence rates of the two HCC groups were relatively high. We found that critical tumor markers for recurrence differed between the two diseases.

Fatty liver is an important clinical feature not only in alcoholic and non-alcoholic fatty liver diseases, but in other chronic liver diseases as well. Our aim was to elucidate the effect and relationship between habitual alcohol intake and obesity in the development of fatty liver disease. We enrolled 8,029 subjects undergoing abdominal ultrasonography with general medical examinations, and analyzed the factors associated with fatty liver based on daily alcohol intake, body mass index (BMI), and waist circumference. For fatty liver, BMI, waist circumference, total cholesterol, triglycerides, and fasting plasma glucose were significant and independent risk factors. Heavy alcohol intake (50 g/day) was a significant risk factor for fatty liver in women (odds ratio [OR], 3.35). Analysis based on the presence or absence of obesity revealed that moderate alcohol intake was a significant negative risk factor for fatty liver in both male and female obese (BMI ≥25 kg/m2) subjects (OR, 0.74 for non-obese and 0.39 for obese patients, respectively). Heavy alcohol intake was also a significant negative risk factor in obese males (0.62). In contrast, heavy alcohol intake was a risk factor in non-obese males (OR, 1.29) and in all females (OR, 2.22 for non-obese and 6.6 for obese patients, respectively). The influence of alcohol intake on fatty liver differed depending on the level of alcohol consumption, gender, and the presence of obesity, and showed biphasic effects.

Older patients with chronic hepatitis C have a lower virological response to interferon (IFN) treatment compared to younger patients. The efficacy of telaprevir (TVR) and PEG-IFN plus ribavirin combination therapy and the predictive value of recently identified IFN lambda (IFNL) 4 polymorphisms on the outcome of therapy for older patients have not been addressed.We assessed predictive factors for sustained virological response (SVR) to triple therapy in 226 younger (≤65 years) and 87 older (65 years) Japanese patients with chronic genotype 1 hepatitis C. IFNL4 polymorphism ss469415590 was analyzed by Invader assay.The SVR rate for older patients was slightly lower than for younger patients (69 vs. 82%, P = 0.043). In the older group, the SVR rate for patients with the IFNL4 TT/TT genotype was significantly higher than patients with TT/ΔG or ΔG/ΔG genotypes (81.8 and 42.9%, P = 0.003). In multivariate regression analysis, rapid virological response (OR 36.601, P = 0.002) and IFNL4 TT/TT genotype (OR 19.502, P = 0.009) were identified as significant independent predictors for SVR in older patients. Treatment-related decreases in hemoglobin and increases in serum creatinine were higher in older patients than younger patients. Reduction of initial TVR dose to 1,500 mg per day alleviated these adverse events without compromising SVR rate in older patients.Analysis of IFNL4 polymorphisms is a valuable predictor in older patients receiving TVR triple therapy. 1,500 mg per day is a suitable initial TVR dose for older Japanese patients.

The prevalence of nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome have been increasing worldwide. The associations between metabolic factors and the histologic severity of NAFLD have not yet been clarified. Therefore, we studied the relationships between relevant metabolic factors and the histological severity of NAFLD. In a cross-sectional multicenter study conducted in Japan, we examined 1,365 biopsy-proven NAFLD patients. The frequencies of underlying lifestyle-related diseases and their relationships to the NAFLD histology were investigated. The hepatic fibrosis stages (Stage 0/1/2/3/4) were 22.6/34.1/26.7/14.5/2.1 (%) in the male patients, and 16.2/31.7/23.9/21.6/6.6 (%) in the female patients. Dyslipidemia was present in 65.7 % (hypertriglyceridemia, 45.3 %; increased low-density lipoprotein cholesterol, 37.5 %; decreased high density lipoprotein cholesterol, 19.5 %) of patients. Hypertension was present in 30.2 %, and diabetes mellitus (DM) in 47.3 %. The fibrosis stage increased with age, especially in postmenopausal females. The body mass index was positively correlated with the fibrosis stage. Deterioration of glucose control was positively correlated with the fibrosis stage, this correlation being more prominent in females. Multivariate analysis identified age and DM as significant risk factors for advanced fibrosis. No significant correlation of the fibrosis stage was observed with hypertension. There was a negative correlation between the serum triglyceride levels and the fibrosis stage. DM appeared to be a significant risk factor for advanced fibrosis in patients with NAFLD, and would therefore need to be properly managed to prevent the progression of NAFLD.

The prevalence of nonalcoholic fatty liver disease (NAFLD) has been increasing. This study aimed to assess the recent prevalence of NAFLD and to predict the prevalence of nonalcoholic steatohepatitis (NASH) with liver fibrosis using established scoring systems in the general population. A cross-sectional study was conducted among 8352 subjects who received health checkups from 2009 to 2010 in three health centers in Japan. Subjects with an intake over 20 g of alcohol/day or with other chronic liver diseases were excluded. Fatty liver was detected by ultrasonography. The probability of NASH with advanced fibrosis was calculated according to the body mass index, age, ALT, and triglyceride (BAAT) and FIB-4 (based on age, aspartate aminotransferase and alanine aminotransferase levels, and platelet counts) indices. A total of 5075 subjects were enrolled. The overall prevalence of NAFLD was 29.7%. There was a significant threefold difference in the mean prevalence between males (41.0%) and females (17.7%). This prevalence showed a linear increase with body mass index, triglycerides, and low-density lipoprotein cholesterol regardless of threshold values, even without obesity. The estimated prevalence of NASH according to the BAAT index ≥3 was 2.7%, and according to the FIB-4 index it was 1.9%. The prevalence of NAFLD has increased in the general population, especially in males. There is a linear relationship between the prevalence of NAFLD and various metabolic parameters, even in nonobese subjects. The prevalence of NASH with advanced fibrosis is estimated to be considerably high in subjects with NAFLD.

Liver histology is the gold standard for the diagnosis of nonalcoholic steatohepatitis (NASH). Noninvasive, simple, reproducible, and reliable biomarkers are greatly needed to differentiate NASH from nonalcoholic fatty liver disease (NAFLD). To construct a scoring system for predicting NASH, 177 Japanese patients with biopsy-proven NAFLD were enrolled. To validate the scoring system, 442 biopsy-proven NAFLD patients from eight hepatology centers in Japan were also enrolled. In the estimation group, 98 (55%) patients had NASH. Serum ferritin [≥200 ng/ml (female) or ≥300 ng/ml (male)], fasting insulin (≥10 μU/ml), and type IV collagen 7S (≥5.0 ng/ml) were selected as independent variables associated with NASH, by multilogistic regression analysis. These three variables were combined in a weighted sum [serum ferritin ≥200 ng/ml (female) or ≥300 ng/ml (male) = 1 point, fasting insulin ≥10 μU/ml = 1 point, and type IV collagen 7S ≥5.0 ng/ml = 2 points] to form an easily calculated composite score for predicting NASH, called the NAFIC score. The area under the receiver operating characteristic (AUROC) curve for predicting NASH was 0.851 in the estimation group and 0.782 in the validation group. The NAFIC AUROC was the greatest among several previously established scoring systems for detecting NASH, but also for predicting severe fibrosis. NAFIC score can predict NASH in Japanese NAFLD patients with sufficient accuracy and simplicity to be considered for clinical use.

It is suggested that nonalcoholic fatty liver disease (NAFLD), including nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH), can be associated with insomnia and gastro-esophageal reflux disease (GERD). The relationship between GERD and insomnia in subjects with biopsy-proven NAFLD was investigated. This study enrolled 123 patients with biopsy-proven NAFLD. Insomnia was assessed by the Athens Insomnia Scale (AIS), a self-assessment psychometric instrument designed to quantify sleep difficulty based on ICD-10 criteria; AIS scores ≥ 6 were considered positive for insomnia. GERD symptoms were evaluated using a frequency scale for the symptoms of GERD (FSSG); FSSG scores ≥ 8 were considered positive. Logistic regression models were used to evaluate the association of insomnia with GERD, after adjusting for potential confounders. Thirteen patients with GERD were treated with the proton pump inhibitor rabeprazole (RPZ; 10 mg/day), for 12 weeks. Of the 123 patients, 76 (62 %) were female and 87 (71 %) were obese, with 34 (28 %) having AIS scores ≥ 6 and 31 (25 %) having FSSG scores ≥ 8. Liver biopsy revealed that 40 patients (33 %) had NAFL and 83 (67 %) had NASH. FSSG and AIS scores were similar in the two groups. HOMA-IR, FSSG scores and γGT (GGT) concentrations were significantly higher in insomniacs than in non-insomniacs. Logistic regression analysis demonstrated that FSSG score and GGT concentration were independently associated with insomnia. RPZ treatment resulted in significantly reductions in both AIS and FSSG scores. Nearly 30 % of patients with biopsy-proven NAFLD had insomnia, which was related to GGT and GERD and could be relieved by RPZ treatment.

We investigated the effects of dental infection with Porphyromonas gingivalis (P.g.), an important periodontal pathogen, on NASH progression, by feeding mice a high fat diet (HFD)and examining P.g. infection in the liver of NASH patients. C57BL/6J mice were fed either chow-diet (CD) or HFD for 12 weeks, and then half of the mice in each group were infected with P.g. from the pulp chamber (HFD-P.g.(−), HFD-P.g.(+), CD-P.g.(−) and CD-P.g.(+)). Histological and immunohistochemical examinations, measurement of serum lipopolysaccharide (LPS) levels and ELISA for cytokines in the liver were performed. We then studied the effects of LPS from P.g. (P.g.-LPS) on palmitate-induced steatotic hepatocytes in vitro, and performed immunohistochemical detection of P.g. in liver biopsy specimens of NASH patients. Serum levels of LPS are upregulated in P.g.(+) groups. Steatosis of the liver developed in HFD groups, and foci of Mac2-positive macrophages were prominent in HFD-P.g.(+). P.g. was detected in Kupffer cells and hepatocytes. Interestingly, areas of fibrosis with proliferation of hepatic stellate cells and collagen formation were only observed in HFD-P.g.(+). In steatotic hepatocytes, expression of TLR2, one of the P.g.-LPS receptors, was upregulated. P.g.-LPS further increased mRNA levels of palmitate-induced inflammasome and proinflammatory cytokines in steatotic hepatocytes. We demonstrated for the first time that P.g. existed in the liver of NASH patients with advanced fibrosis. Dental infection of P.g. may play an important role in NASH progression through upregulation of the P.g.-LPS-TLR2 pathway and activation of inflammasomes. Therefore, preventing and/or eliminating P.g. infection by dental therapy may have a beneficial impact on management of NASH.

The severity of liver fibrosis must be estimated to determine the prognosis, for surveillance, and for optimal treatment of nonalcoholic fatty liver disease (NAFLD). However, the severity of hepatic fibrosis tends to be underestimated in patients with normal ALT.We investigated histological data and scoring systems (FIB-4 index, NAFLD fibrosis score, BARD score, and AST/ALT ratio) of 1,102 liver-biopsy-confirmed NAFLD patients.A total of 235 NAFLD patients with normal ALT were estimated to exist. The ratio of advanced fibrosis (stage 3-4) was seen in 16.1 % of subjects with normal ALT. Scoring systems, especially the FIB-4 index and NAFLD fibrosis score, were clinically very useful (AUROC0.8), even in patients with normal ALT. Furthermore, with resetting of the cutoff values, the FIB-4 index (1.659) and NAFLD fibrosis score (0.735) were found to have a higher sensitivity and higher specificity for the prediction of advanced fibrosis, and all of these scoring systems (FIB-4 index, NAFLD fibrosis score, BARD score, and AST/ALT ratio) had higher negative predictive values (90.3 %). By using the resetting cutoff value, liver biopsy could have been avoided in 60.4 % (FIB-4), 66.4 % (NAFLD fibrosis score), 51.9 % (BARD score), and 62.1 % (AST/ALT ratio).We reset the cutoff values of numerous non-invasive scoring systems to improve their clinical usefulness in the prediction of liver fibrosis in NAFLD patients with normal ALT, and these non-invasive scoring systems with the reset cutoff values could be of substantial benefit to reduce the number of liver biopsies performed.

We aimed to identify risk factors contributing to the exacerbation of esophageal varices (EV) or portosystemic encephalopathy after hepatitis C virus (HCV) eradication with interferon (IFN) therapy in patients with compensated cirrhosis. Also, the prognosis after HCV eradication was analyzed. Fifty-two patients with sustained virological response to IFN treatment for HCV-related compensated cirrhosis were enrolled in this retrospective cohort study. At the achievement of HCV eradication, in 31 of the 52 patients (60 %), feeding vessels for EVs (left gastric vein, posterior gastric vein, short gastric vein) were shown, and in 18 patients (35 %) there were extrahepatic portosystemic shunts (paraesophageal vein, paraumbilical vein, and splenorenal shunt). Although the HCV eradication was successful, significant improvements were not observed in portosystemic collateral vessels 1 year after HCV eradication, and EVs were exacerbated in 19 (36 %) patients. The cumulative 1- and 3-year rates of EV exacerbation were 13 % and 49 %, respectively. By multivariate analysis, the existence of feeding vessels for EVs at HCV eradication was an independent predictive factor for the exacerbation of EVs (P = 0.009). Seven patients who had an extrahepatic portosystemic shunt at HCV eradication developed portosystemic encephalopathy during follow up. The 1-, 3-, and 5-year incidences of portosystemic encephalopathy were 6, 21, and 34 %, respectively. The cumulative 5-year survival rate of the cohort was 81 %. Two patients died of hepatocellular carcinoma (HCC). Our findings suggest that the existence of radical portosystemic collateral vessels at successful HCV eradication increases the risk of the exacerbation of EVs and the incidence of portosystemic encephalopathy in patients with HCV-related cirrhosis.

This study is a post-hoc analysis of a subset of patients who participated in our multi-institutional case-control study that evaluated the effects of pitavastatin in patients with non-alcoholic fatty liver disease (NAFLD) with hypercholesterolemia.Serum samples of fifteen patients with biopsy-proven NAFLD with dyslipidemia were investigated. Serum markers of lipid metabolism were quantified by liquid chromatography-mass spectrometry (LC-MS)/MS. These data were then compared with those of 36 sex- and age-matched healthy controls. In addition, changes in these markers produced by treatment with pitavastatin were evaluated.Serum non-cholesterol sterols, reflecting intestinal cholesterol absorption, were significantly lower in the NAFLD patients compared to the controls, and the cholesterol synthesis marker, the ratio of lathosterol to cholesterol, was not significantly different between the two groups. Serum proportions of liver X receptor α (LXRα) ligand oxysterols (ratios to cholesterol) were significantly elevated in the NAFLD patients compared to the controls. The sum of oxysterols relative to cholesterol and the homeostasis model assessment as an index of insulin resistance (HOMA-IR) were significantly correlated. The marker representing cholesterol synthesis was significantly suppressed by pitavastatin treatment, from 3 months after initiation of the treatment, and the suppression remained significant during the observation period. The markers representing cholesterol absorption were unchanged at 3 months, but had significantly increased at 12 months. Serum oxysterol levels relative to cholesterol maintained high values and did not change significantly during the 12-month period of treatment.We speculate that serum LXRα ligand oxysterol levels (relative to cholesterol) could be surrogate markers of insulin resistance, and that high oxysterol levels in the circulation may play an important role in the development of hepatic and peripheral insulin resistance followed by NAFLD.

Several single nucleotide polymorphisms (SNPs) within the interleukin 28B (IL28B) locus are associated with sustained viral response in chronic hepatitis C (HCV) patients who were treated with pegylated interferon (PEG-IFN) plus ribavirin (RBV) combination therapy. Recently, an association between γ-GTP level and IL28B genotype was identified. In this study, the relationship between IL28B genotype and liver steatosis was analyzed. One hundred fifty-three patients who underwent liver biopsy before PEG-IFN plus RBV combination therapy were enrolled. The level of liver steatosis was measured using a BIOREVO BZ-9000 microscope, and the proportion of fatty change and clear cell change were calculated using Dynamic cell count BZ-H1C software. IL28B SNP genotype (rs8099917) was determined using the Invader Assay. Vesicular change was significantly associated with body mass index (BMI), HCV RNA titer, serum aspartate aminotransferase, γ-GTP, IL28B genotype and liver fibrosis level (P

The severity of liver fibrosis is known to be a good indicator for surveillance, and for determining the prognosis and optimal treatment of nonalcoholic fatty liver disease (NAFLD). However, it is virtually impossible to carry out liver biopsies in all NAFLD patients. The purpose of this study was to investigate the clinical usefulness of measuring the platelet count for predicting the severity of liver fibrosis in a large retrospective cohort of Japanese patients with NAFLD.A total of 1,048 patients with liver-biopsy-confirmed NAFLD seen between 2002 and 2008 were enrolled from nine hepatology centers in Japan. Laboratory evaluations were performed for all patients.A linear decrease of the platelet count with increasing histological severity of hepatic fibrosis was revealed. The area under the receiver operating characteristic curve estimating the diagnostic performance of the platelet count for hepatic fibrosis Stage 3 was 0.774 (optimal cutoff value, 19.2 × 10(4)/μl; sensitivity, 62.7%; specificity, 76.3%), and that for Stage 4 was 0.918 (optimal cutoff value, 15.3 × 10(4)/μl; sensitivity, 80.5%; specificity, 88.8%).The platelet count may be an ideal biomarker of the severity of fibrosis in NAFLD patients, because it is simple, easy to measure and handle, cost-effective, and accurate for predicting the severity of fibrosis. Furthermore, by using the platelet count cutoff value validated in our multiple large trials, efficient recruitment of NAFLD patients may be facilitated.

Advanced glycation endproducts (AGEs), final reaction products of protein with sugars, are known to contribute to various disorders, including diabetes, aspects of aging, and neurodegenerative diseases. Recently, we reported elevated levels of serum AGEs in patients with nonalcoholic steatohepatitis (NASH); further, we found that AGEs induced the generation of reactive oxygen species followed by the proliferation and activation of hepatic stellate cells, a major contributor to liver fibrosis. In this study, to explore the clinical usefulness of AGEs as a biomarker for the attenuation of NASH, we investigated whether the treatment of NASH with dyslipidemia could decrease serum levels of AGEs.This study included 43 patients with biopsy-proven NASH with dyslipidemia. Serum glyceraldehyde-derived AGE measurements and clinical laboratory tests were performed periodically during an open-label study of atorvastatin (10 mg daily) for 12 months. Standard weight-loss counseling was continued during the treatment period. Oral glucose tolerance tests and liver density assessment by computerized tomography were performed before and after treatment. Follow-up liver biopsy was performed in 22 patients.All 43 patients had dyslipidemia. The body mass indexes and serum glucose levels did not change during the treatment. After the treatment, NASH-related metabolic parameters were significantly improved. Serum glyceraldehyde-derived AGE levels were significantly decreased (10.4 +/- 3.8 and 2.5 +/- 1.1 IU/mL before and after treatment, respectively). The steatosis grade and nonalcoholic fatty liver disease (NAFLD) activity score were significantly improved.The present data demonstrated that atorvastatin decreased the serum levels of AGEs in NASH patients with dyslipidemia and suggest the usefulness of AGEs as a biomarker for the attenuation of NASH.

Advanced glycation end products (AGEs), final reaction products of protein with sugars, are known to contribute to diabetes-related complications. We have recently demonstrated high levels of serum AGEs in patients with nonalcoholic steatohepatitis (NASH). However, direct evidence for the participation of AGEs in hepatic inflammation and fibrosis has not been shown. To explore the pathogenesis of NASH, we examined the biological infl uence of AGEs on hepatic stellate cells (HSCs) in vitro.An established human HSC line, LI90, was exposed to a glyceraldehyde-derived-AGE (glycer-AGE), and the phenotypical changes of the LI90 cells were investigated. Intracellular formation of reactive oxygen species (ROS) was measured using a fl uorescent probe. Cell proliferation was examined by MTS assay. Fibrogenic marker gene expression was analyzed by quantitative real-time polymerase chain reaction. The production of monocyte chemoattractant protein 1 (MCP-1) was assessed by enzyme-linked immunosorbent assay.The expression of AGE receptor was confirmed in LI90 cells at the mRNA and protein levels. In addition to increasing intracellular ROS generation, glycer-AGE upregulated fibrogenic genes such as those encoding for alpha-smooth muscle actin, transforming growth factor-beta1, and collagen type Ialpha2. The expression of MCP-1 mRNA in LI90 cells as well as its secretion into the culture medium was significantly increased in response to AGEs. These changes were attenuated by treatment with the antioxidant N-acetylcysteine.These data indicate that AGEs induce ROS generation and intensify the proliferation and activation of HSCs, supporting the possibility that antioxidants may represent a promising treatment for prevention of the development of hepatic fibrosis in NASH.

We appreciate the interest shown by Dr. Yusuf Yilmaz in his recent letter as well as his comments. As he pointed out, the AGEs–RAGE axis is emerging as a core piece in the pathophysiology of insulin resistance, NAFLD and NASH. We have therefore analyzed the serum levels of circulating soluble isoforms of RAGE (sRAGE) in NASH patients with metabolic disorders before and during their treatments. We have found that decreased levels of sRAGE prior to treatment initiation were correlated with deteriorated post-treatment histological findings and that sRAGE levels appeared to have increased after the treatments (data not published). Based on our data, we suggest that not only atorvastatin treatment but also other successful treatments could increase the serum levels of sRAGE. Yilmaz et al. have examined the relationship between circulating levels of sRAGE and NAFLD in humans and demonstrated that levels of sRAGE are highly reduced in the setting of NASH and inversely correlated with ALT and AST levels. Our results will support these findings. In our paper on the effects of atorvastatin treatment on serum levels of AGEs in NASH patients with dyslipidemia, our first priority was to show the important aspects of serum AGEs as a marker for oxidative stress as well for the diabetic condition. As such, we will provide data on the relationship between sRAGE and AGEs before and during the various treatments based upon the AGEs–RAGE axis theory in the future.

We appreciate the letter from Professor Ilker Tasci, M.D., showing his interest in our article and making some comments. He pointed that about one-third of the study population had overt diabetes mellitus. Because the base levels of HbA1c were less than 6.5 in the studied population at entry to the study, 75-g oral glucose tolerance tests were undertaken to examine the prevalence of postprandial hyperglycemia and diabetes mellitus. Accordingly, antidiabetic medications were not administered; only ordinary diet counseling was provided. As a result, none of the patients experienced deteriorating conditions during the study, as shown in the tables in the article. As to the relatively high prevalence of hypertensive individuals, 63% of patients had already been treated properly with calcium antagonists (amlodipine), and this did not change during the study period. The rest of the hypertensive individuals were not treated because their blood pressure levels were slightly above the normal limit. For these reasons, we could not present adjusted information. In this study, because the changes in AGEs levels were not associated with impaired glucose tolerance, we would like to conclude that not only the diabetic condition, but also the oxidative situation affects the AGEs levels, and AGEs might become a candidate biomarker for NASH without overt diabetes mellitus (HbA1c less than 6.5). As Dr. Tasci pointed out, there are reports about the influence of AGEs level medications for diabetes mellitus and hypertension, including our reports. Finally, Dr. Tasci commented that ‘‘atorvastatin should be taken as a safe agent for dyslipidemia management in people with NASH, but more is needed to indicate it as an agent to ‘treat’ NASH with dyslipidemia for ALT normalization and histological recovery.’’ This comment is important, but, because of the small numbers of samples and less recovery of fibrosis, further analyses and randomized placebo-controlled trials are needed. At least we have shown that atorvastatin is a safe agent and has some beneficial effects on histological recovery when managing dyslipidemia patients with NASH.