Livers Of Non-alcoholic Steatohepatitis Patients Research Articles

The role of C5aR1-mediated hepatic macrophage efferocytosis in NASH

Non-alcoholic fatty liver disease (NAFLD) has become the first major chronic liver disease in developed countries. 10–20% of NAFLD patients will progress to non-alcoholic steatohepatitis (NASH), and up to 25% of NASH patients may develop cirrhosis within 10 years. Therefore, it is critical to find key targets that may treat this disease. Here, we identified C5aR1 as a highly-expressed gene in NASH mouse model through analyzing Gene Expression Omnibus (GEO) database and confirmed its higher expression in livers of NASH patients than that of NAFL patients. Meanwhile, we verified its positive correlation with patients’ serum alanine transaminase (ALT) and aspartate transaminase (AST) levels. In vivo and in vitro experiments revealed that knocking down C5aR1 in liver significantly reduced liver weight ratio and serum ALT and AST levels and attenuated inflammatory cell infiltration and cell apoptosis in the liver of NASH mice as well as enhanced the efferocytotic ability of liver macrophages, suggesting that C5aR1 may play a crucial role in the efferocytosis of liver macrophages. Furthermore, we also found that the expression levels of nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing protein 3 (NLRP3), caspase-1, IL-1β and other inflammation-related factors in the liver were significantly reduced. Our work demonstrates a potential mechanism of how C5aR1 deficiency protects against diet-induced NASH by coordinating the regulation of inflammatory factors and affecting hepatic macrophage efferocytosis.

HSD17B13 liquid-liquid phase separation promotes leukocyte adhesion in chronic liver inflammation.

The rs72613567:TA polymorphism in 17-beta hydroxysteroid dehydrogenase 13 (HSD17B13) has been found to reduce the progression from steatosis to nonalcoholic steatohepatitis. In this study, we sought to define the pathogenic role of HSD17B13 in triggering liver inflammation. Here we find that HSD17B13 forms liquid-liquid phase separation (LLPS) around lipid droplets in the livers of nonalcoholic steatohepatitis patients. The dimerization of HSD17B13 supports the LLPS formation and promotes its enzymatic function. HSD17B13 LLPS increases the biosynthesis of platelet activating factor (PAF), which in turn promotes fibrinogen synthesis and leukocyte adhesion. Blockade of PAFR or STAT3 pathway inhibited the fibrinogen synthesis and leukocyte adhesion. Importantly, adeno-associated viral-mediated xeno-expression of human HSD17B13 exacerbated western diet/carbon tetrachloride-induced liver inflammation in Hsd17b13-/- mice. In conclusion, our results suggest that HSD17B13 LLPS triggers liver inflammation by promoting PAF-mediated leukocyte adhesion, and targeting HSD17B13 phase transition could be a promising therapeutic approach for treating hepatic inflammation in chronic liver disease.

Terf2ip deficiency accelerates non-alcoholic steatohepatitis through regulating lipophagy and fatty acid oxidation via Sirt1/AMPK pathway

Background & aimsOur previous study has demonstrated that Telomeric repeat-binding factor 2-interacting protein 1(Terf2ip), played an important role in hepatic ischemia reperfusion injury. This study is aimed to explore the function and mechanism of Terf2ip in non-alcoholic steatohepatitis (NASH). MethodsThe expression of Terf2ip was detected in liver tissue samples obtained from patients diagnosed with NASH. Mice NASH models were constructed by fed with high-fat diet (HFD) or methionine/choline deficient diet (MCD) in Terf2ip knockout and wild type (WT) mice. To further investigate the role of Terf2ip in NASH, adeno-associated viruses (AAV)-Terf2ip was administrated to mice. ResultsWe observed a significant down-regulation of Terf2ip levels in the livers of NASH patients and mice NASH models. Terf2ip deficiency was associated with an exacerbation of hepatic steatosis in mice under HFD or MCD. Additionally, Terf2ip deficiency impaired lipophagy and fatty acid oxidation (FAO) in NASH models. Mechanically, we discovered that Terf2ip bound to the promoter region of Sirt1 to regulate Sirt1/AMPK pathway activation. As a result, Terf2ip deficiency was shown to inhibit lipophagy through the AMPK pathway, while the activation of Sirt1 alleviated steatohepatitis in the livers of mice. Finally, re-expression of Terf2ip in hepatocyes alleviated liver steatosis, inflammation, and restored lipophagy. ConclusionsThese results revealed that Terf2ip played a protective role in the progression of NASH through regulating lipophagy and FAO by binding to Sirt1 promoter. Our findings provided a potential therapeutic target for the treatment of NASH.

Hepatic Pin1 Expression, Particularly in Nuclei, Is Increased in NASH Patients in Accordance with Evidence of the Role of Pin1 in Lipid Accumulation Shown in Hepatoma Cell Lines.

Our previous studies using rodent models have suggested an essential role for Pin1 in the pathogenesis of non-alcoholic steatohepatitis (NASH). In addition, interestingly, serum Pin1 elevation has been reported in NASH patients. However, no studies have as yet examined the Pin1 expression level in human NASH livers. To clarify this issue, we investigated the expression level and subcellular distribution of Pin1 in liver specimens obtained using needle-biopsy samples from patients with NASH and healthy liver donors. Immunostaining using anti-Pin1 antibody revealed the Pin1 expression level to be significantly higher, particularly in nuclei, in the livers of NASH patients than those of healthy donors. In the samples from patients with NASH, the amount of nuclear Pin1 was revealed to be negatively related to serum alanine aminotransferase (ALT), while tendencies to be associated with other serum parameters such as aspartate aminotransferase (AST) and platelet number were noted but did not reach statistical significance. Such unclear results and the lack of a significant relationship might well be attributable to our small number of NASH liver samples (n = 8). Moreover, in vitro, it was shown that addition of free fatty acids to medium induced lipid accumulation in human hepatoma HepG2 and Huh7 cells, accompanied with marked increases in nuclear Peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (Pin1), in accordance with the aforementioned observations in human NASH livers. In contrast, suppression of Pin1 gene expression using siRNAs attenuated the free fatty acid-induced lipid accumulation in Huh7 cells. Taken together, these observations strongly suggest that increased expression of Pin1, particularly in hepatic nuclei, contributes to the pathogenesis of NASH with lipid accumulation.

MCAD activation by empagliflozin promotes fatty acid oxidation and reduces lipid deposition in NASH.

Medium-chain acyl-CoA dehydrogenase (MCAD) is one of the significant enzymes involved in the β-oxidation of mitochondrial fatty acids. MCAD deficiency affects the β-oxidation of fatty acid and leads to lipid deposition in multiple organs, but little is known about its importance in nonalcoholic steatohepatitis (NASH). Empagliflozin is revealed to effectively improve NASH by increasing research, whereas the specific mechanism still has to be explored. Human liver tissues of patients with or without NASH were obtained for proteomic analysis to screen proteins of interest. db/db mice were given empagliflozin by gavage for 8 weeks. The expression of MCAD and signaling molecules involved in hepatic lipid metabolism was evaluated in human liver, mice and HL7702 cells. We found that the MCAD levels in the liver were significantly reduced in NASH patients compared to patients without NASH. Protein-protein interaction network analysis showed that MCAD was highly correlated with forkhead box A2 (FOXA2) and protein kinase AMP-activated catalytic subunit alpha (PRKAA). AMPK/FOXA2/MCAD signaling pathway was detected to be inhibited in the liver of NASH patients. Decreased expression of MCAD was also observed in the livers of db/db mice and hepatocyte treated with palmitic acid and glucose. Of note, empagliflozin could upregulate MCAD expression by activating AMPK/FOXA2 signaling pathway, reduce lipid deposition and improve NASH in vivo and in vitro. This research demonstrated that MCAD is a key player of hepatic lipid deposition and its targeting partially corrects NASH. MCAD thus may be a potential therapeutic target for the treatment of NASH.

Bile Acids, Gut Microbiome and the Road to Fatty Liver Disease.

This article describes the complex interactions occurring between diet, the gut microbiome, and bile acids in the etiology of fatty liver disease. Perhaps 25% of the world's population may have nonalcoholic fatty liver disease (NAFLD) and a significant percentage (∼20%) of these individuals will progress to nonalcoholic steatohepatitis (NASH). Currently, the only recommended treatment for NAFLD and NASH is a change in diet and exercise. A Western-type diet containing high fructose corn syrup, fats, and cholesterol creates gut dysbiosis, increases intestinal permeability and uptake of LPS causing low-grade chronic inflammation in the body. Fructose is a "lipogenic" sugar that induces long-chain fatty acid (LCFA) synthesis in the liver. Inflammation decreases the oxidation of LCFA, allowing fat accumulation in hepatocytes. Hepatic bile acid transporters are downregulated by inflammation slowing their enterohepatic circulation and allowing conjugated bile acids (CBA) to increase in the serum and liver of NASH patients. High levels of CBA in the liver are hypothesized to activate sphingosine-1-phosphate receptor 2 (S1PR2), activating pro-inflammatory and fibrosis pathways enhancing NASH progression. Because inflammation appears to be a major physiological driving force in NAFLD/NASH, new drugs and treatment protocols may require the use of anti-inflammatory compounds, such as berberine, in combination with bile acid receptor agonists or antagonists. Emerging new molecular technologies may provide guidance in unraveling the complex physiological pathways driving fatty liver disease and better approaches to prevention and treatment. © 2021 American Physiological Society. Compr Physiol 11:1-12, 2021.

Integrated Analysis of Key Genes and Pathways Involved in Nonalcoholic Steatohepatitis Improvement After Roux-en-Y Gastric Bypass Surgery.

BackgroundAs the incidence of nonalcoholic fatty liver disease (NAFLD) increases globally, nonalcoholic steatohepatitis (NASH) has become the second common cause of liver transplantation for liver diseases. Recent evidence shows that Roux-en-Y gastric bypass (RYGB) surgery obviously alleviates NASH. However, the mechanism underlying RYGB induced NASH improvement is still elusive.MethodsWe obtained datasets, including hepatic gene expression data and histologic NASH status, at baseline and 1 year after RYGB surgery. Differentially expressed genes (DEGs) were identified comparing gene expression before and after RYGB surgery in each dataset. Common DEGs were obtained between both datasets and further subjected to functional and pathway enrichment analysis. Protein–protein interaction (PPI) network was constructed, and key modules and hub genes were also identified.ResultsIn the present study, GSE106737 and GSE83452 datasets were included. One hundred thirty common DEGs (29 up-regulated and 101 down-regulated) were identified between GSE106737 and GSE83452 datasets. KEGG analysis showed that mineral absorption, IL-17 signaling pathway, osteoclast differentiation, and TNF signaling pathway were significantly enriched. Based on the PPI network, IGF1, JUN, FOS, LDLR, TYROBP, DUSP1, CXCR4, ATF3, CXCL2, EGR1, SAA1, CTSS, and PPARA were identified as hub genes, and three functional modules were also extracted.ConclusionThis study identifies the global gene expression change in the liver of NASH patients before and after RYGB surgery in a bioinformatic method. Our findings will contribute to the understanding of molecular biological changes underlying NASH improvement after RYGB surgery.

STING expression in monocyte-derived macrophages is associated with the progression of liver inflammation and fibrosis in patients with nonalcoholic fatty liver disease

The stimulator of interferon genes (STING) in macrophages plays a crucial role in nonalcoholic fatty liver disease (NAFLD) progression. However, there is a lack of evidence from large samples of patients to validate a deleterious role for STING in NAFLD. Moreover, sources of STING-expressing cells that are related to NAFLD remain to be definitively characterized. To investigate STING expression and explore its correlation with NAFLD progression in human subjects, our study involved liver samples from 98 NAFLD subjects and 8 controls. STING and p-TBK1 expression in nonparenchymal liver cells was analyzed and correlated with NAFLD pathological features. Numbers of STING+ cells were increased in livers from nonalcoholic steatohepatitis (NASH) patients compared with controls, especially in the liver portal tract of NASH patients with fibrosis (p < 0.05). Moreover, numbers of STING+ cells in livers of NASH patients were increased with aggravation of inflammation grade and fibrosis stage (p < 0.05). STING was mainly expressed in macrophages, including monocyte-derived macrophages (CCR2+, S100A9+), Kupffer cells (CD68+) and CD163+ macrophages. Compared with controls, numbers of STING+/CCR2+ and STING+/S100A9+ cells were significantly increased in livers from NASH patients with fibrosis and positively correlated with liver inflammation grade and fibrosis stage (p < 0.05). However, numbers of STING+/CD68+ and STING+/CD163+ cells were significantly increased in livers from NASH patients with advanced fibrosis and correlated only with aggravation of fibrosis stage (p < 0.05). Furthermore, compared with controls, NASH patients exhibited significantly increased STING+/p-TBK1+ cell numbers. In a coculture system, the amount of p-TBK1 and the mRNAs of IL1β and IL6 in THP1 macrophages, as well as the amount of α-SMA and the mRNAs of Col1a1, Fn and TGFβ1 in LX2 cells were significantly increased upon STING activation in macrophages (p < 0.05). Therefore, increased STING expression in MoMFs appears to be indicative of NAFLD progression, and STING could be a new target for NAFLD therapy.

NCOA5 deficiency promotes a unique liver protumorigenic microenvironment through p21WAF1/CIP1 overexpression, which is reversed by metformin.

Prevention and treatment options for hepatocellular carcinoma (HCC) are presently limited, underscoring the necessity for further elucidating molecular mechanisms underlying HCC development and identifying new prevention and therapeutic targets. Here, we demonstrate a unique protumorigenic niche in the livers of Ncoa5+/− mouse model of HCC, which is characterized by altered expression of a subset of genes including p21WAF1/CIP1 and proinflammatory cytokine genes, increased putative hepatic progenitors, and expansions of activated and tissue-resident memory (TRM) CD8+ T lymphocytes, myeloid-derived suppressor cells (MDSCs) and alternatively activated M2 macrophages. Importantly, prophylactic metformin treatment reversed these characteristics including aberrant p21WAF1/CIP1 expression and subsequently reduced HCC incidence in Ncoa5+/− male mice. Heterozygous deletion of the p21WAF1/CIP1 gene alleviated the key features associated with the protumorigenic niche in the livers of Ncoa5+/− male mice. Moreover, transcriptomic analysis reveals that preneoplastic livers of Ncoa5+/− mice are similar to the livers of non-alcoholic steatohepatitis patients as well as the adjacent noncancerous liver tissues of a subset of HCC patients with a relatively poor prognosis. Together, our results suggest that p21WAF1/CIP1 overexpression is essential in the development of pro-tumorigenic microenvironment induced by NCOA5 deficiency and metformin prevents HCC development via alleviating p21WAF1/CIP1 overexpression and protumorigenic microenvironment.

Elevated oxysterol levels in human and mouse livers reflect nonalcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH), a primary cause of liver disease, leads to complications such as fibrosis, cirrhosis, and carcinoma, but the pathophysiology of NASH is incompletely understood. Epstein-Barr virus-induced G protein-coupled receptor 2 (EBI2) and its oxysterol ligand 7α,25-dihydroxycholesterol (7α,25-diHC) are recently discovered immune regulators. Several lines of evidence suggest a role of oxysterols in NASH pathogenesis, but rigorous testing has not been performed. We measured oxysterol levels in the livers of NASH patients by LC-MS and tested the role of the EBI2-7α,25-diHC system in a murine feeding model of NASH. Free oxysterol profiling in livers from NASH patients revealed a pronounced increase in 24- and 7-hydroxylated oxysterols in NASH compared with controls. Levels of 24- and 7-hydroxylated oxysterols correlated with histological NASH activity. Histological analysis of murine liver samples demonstrated ballooning and liver inflammation. No significant genotype-related differences were observed in Ebi2−/− mice and mice with defects in the 7α,25-diHC synthesizing enzymes CH25H and CYP7B1 compared with wild-type littermate controls, arguing against an essential role of these genes in NASH pathogenesis. Elevated 24- and 7-hydroxylated oxysterol levels were confirmed in murine NASH liver samples. Our results suggest increased bile acid synthesis in NASH samples, as judged by the enhanced level of 7α-hydroxycholest-4-en-3-one and impaired 24S-hydroxycholesterol metabolism as characteristic biochemical changes in livers affected by NASH.

RAGE deficiency does not affect non-alcoholic steatohepatitis and atherosclerosis in Western type diet-fed Ldlr\u2212/\u2212 mice

Non-alcoholic fatty liver disease is a spectrum of liver diseases ranging from steatosis only to non-alcoholic steatohepatitis (NASH). The latter is characterized by hepatic inflammation, which increases the risk of cardiovascular disease. It is poorly understood which factors contribute to the onset of hepatic inflammation characterizing the progression from steatosis to NASH. Previously, we demonstrated increased advanced glycation endproducts (AGEs) in the livers of NASH patients. We hypothesise that AGEs play a key role in NASH development by activating their proinflammatory receptor, RAGE. RAGE-deficient mice and wildtype littermates, both on Ldlr−/− background, were fed a Western type diet (WTD) for 3 or 12 weeks. Flow cytometry, histology, gene expression and AGE measurements were performed to evaluate the effects of RAGE deficiency. RAGE-deficient mice displayed reduced weight gain and visceral fat expansion compared to control mice. No difference in adipose tissue inflammation was observed between groups. RAGE deficiency did not affect WTD-induced monocytosis, circulating lipids or hepatic steatosis. WTD-induced hepatic neutrophil and macrophage accumulation and atherosclerotic plaque development was comparable between control and RAGE-deficient mice. No difference in AGE levels was observed. RAGE does not seem to play a major role in the development of NASH or atherosclerosis in a hyperlipidemic mouse model.

Hepatic chemerin mRNA expression is reduced in human nonalcoholic steatohepatitis.

Chemerin is associated with insulin resistance and is expressed in the liver. Nonalcoholic fatty liver disease (NAFLD) is related to impaired insulin sensitivity, but studies evaluating hepatic and serum chemerin in NAFLD resulted in discordant data. Chemerin mRNA was determined in the liver tissue obtained from 33 controls and 76 NAFLD patients. Chemerin serum levels were measured in a different cohort of patients with ultrasound-diagnosed NAFLD and the respective controls. Hepatic stellate cells and hepatocytes were exposed to selected metabolites and nuclear receptor agonists to study the regulation of chemerin. Effect of recombinant chemerin on hepatocyte released proteins was analysed. Hepatic chemerin expression was not related to BMI, gender, type 2 diabetes and hypertension. Chemerin mRNA did not correlate with steatosis and was negatively associated with inflammation, fibrosis and nonalcoholic steatohepatitis (NASH) score. Patients with NASH had lower chemerin mRNA compared to those with borderline NASH and controls. Factors with a role in NASH mostly did not regulate chemerin in the liver cells. Of note, liver X receptor agonist reduced chemerin protein. Serum chemerin was not changed in NAFLD. Levels positively correlated with age, waist-to-hip ratio, systolic blood pressure, serum FGF21 and lipocalin 2, and negatively with transferrin saturation. Chemerin induced FGF21 in supernatants of primary human hepatocytes. Hepcidin, a major regulator of iron homoeostasis and lipocalin 2, were not regulated by chemerin. Chemerin mRNA is reduced in the liver of NASH patients, and liver X receptor seems to have a role herein.

Hepatic FTO expression is increased in NASH and its silencing attenuates palmitic acid-induced lipotoxicity

Non-alcoholic steatohepatitis (NASH) is one of the most common causes of liver failure worldwide. It is characterized by excess fat accumulation, inflammation, and increased lipotoxicity in hepatocytes. Currently, there are limited treatment options for NASH due to lack of understanding of its molecular etiology. In the present study, we demonstrate that the expression of fat mass and obesity associated gene (FTO) is significantly increased in the livers of NASH patients and in a rodent model of NASH. Furthermore, using human hepatic cells, we show that genetic silencing of FTO protects against palmitate-induced oxidative stress, mitochondrial dysfunction, ER stress, and apoptosis in vitro. Taken together, our results show that FTO may have a deleterious role in hepatic cells during lipotoxic conditions, and strongly suggest that up-regulation of FTO may contribute to the increased liver damage in NASH.

Increased frequencies of activated effector CD4+ T cells in the peripheral blood and hepatic tissue of patients with NAFL and NASH

Background: The prevalence of non-alcoholic fatty liver disease (NAFLD) ranges between 20 – 35% in Europe. In 5 to 20% there is a progression from non-alcoholic fatty liver (NAFL) to a non-alcoholic steatohepatitis (NASH) but it is still not understood why some people develop NASH. The current hypothesis about the pathogenesis is a two hit theory. The “first hit” causes a steatosis and the “second hit” in form of bacterial translocation leads to an inflammation and the development of NASH. Hepatic Th17 cell infiltration was observed in a NASH mouse model and higher IL-17 and IL-21 gene expression in human liver of NASH patients. We hypothesized that the phenotype of peripheral CD4+ T cells might be predictive for the degree and quality of hepatic T cell infiltration and histopathology. Aims: Characterization of CD4+ regulatory T cells (Tregs) and conventional CD4+ T cells in peripheral blood and hepatic tissue in patients with NAFL and NASH. Methods: 50 patients with histology-proven NAFL or NASH and 44 healthy controls (HC) were included in this study. PBMCs of peripheral blood and hepatic tissue were characterized by multi-colour FACS analysis. CD4+ T cells were stimulated with PMA and ionomycin for intracellular detection of cytokine production (IL-17, IL-4, INF-g, IL-21). Results: Patients were older and had a higher BMI in comparison to HC. In patients with NAFL and NASH a lower frequency of resting Tregs (CD4+CD45RA+CD25++) was observed in peripheral blood. We found changes in effector CD4+ T cells with higher frequencies of IFN-g+, IL-21+ and IL4+ cells among CD4+ T cells of the peripheral blood of patients. In hepatic tissue, higher frequency of IL17+, IFN-g+, IL21+ and IL4+ cells were measured among CD4+ T cells than in the peripheral blood. CD4+ T cells in peripheral blood and hepatic tissue contained higher frequencies of HLA-DR+, i.e. activated cells. Conclusions: The peripheral blood and hepatic tissue of patients with NAFLD contained higher frequencies of activated effector cells among CD4+ T cells. NAFL patients show a “prehepatitic” immune cell profile very similar to that seen in NASH. Our data suggest that interfering with the effector CD4+ T cell response might prevent progression from NAFL to NASH.

Elevated hepatic chemerin mRNA expression in human non-alcoholic fatty liver disease

Adipose tissue-derived factors link non-alcoholic fatty liver disease (NAFLD) with obesity, which has also been reported for circulating chemerin. On the other hand, hepatic chemerin and chemokine-like receptor 1 (CMKLR1) mRNA expression has not yet been studied in an extensively characterized patient collective. This study was cross-sectional and experimental in design. Liver tissue samples were harvested from 47 subjects and histologically examined according to the NAFLD activity score (NAS). The concentrations of chemerin and CMKLR1 were measured using semi-quantitative real-time PCR, and the concentration of serum chemerin was measured using ELISA. To evaluate potential effects of chemerin and CMKLR1, cultured primary human hepatocytes (PHHs) were exposed to selected metabolites known to play a role in NAFLD (insulin, glucagon, palmitoic acid, and interleukin-6 (IL6)). Chemerin and CMKLR1 mRNA levels were elevated in the human liver. Their expression was correlated with the NAS (R(2)=0.543; P<0.001 and R(2)=0.355; P=0.014 respectively) and was significantly elevated in patients with definite non-alcoholic steatohepatitis (NASH) (P<0.05 respectively). Linear regression analysis confirmed an independent association of liver fibrosis, steatosis, inflammation, and hepatocyte ballooning with hepatic chemerin mRNA expression (P<0.05 respectively). The expression of hepatic chemerin and CMKLR1 was correlated with the measures of obesity (P<0.05). The incubation of PHHs with IL6 significantly increased the expression of CMKLR1 mRNA (P=0.027), while that of chemerin remained unaffected (P>0.05). None of the other metabolites showed an influence (P>0.05). This is the first study to show that chemerin mRNA expression is significantly elevated in the liver of NASH patients and that CMKLR1 expression is upregulated in liver inflammation, whereby IL6 could play a causal role.

Elevated levels of serum advanced glycation end products in patients with non‐alcoholic steatohepatitis

Advanced glycation end products (AGE), senescent macroprotein derivatives formed at an accelerated rate in diabetes, play important roles in the pathogenesis of diabetic vascular complications. Recently, AGE have also been found to be involved in insulin resistance. Although non-alcoholic steatohepatitis (NASH) is generally considered a hepatic manifestation of insulin resistance, there are no reports showing the link of AGE to NASH. The aim of this study was to evaluate the clinical significance of AGE in patients with NASH. Glyceraldehyde-derived AGE levels were assayed from serum obtained from 106 patients: 66 with NASH, 10 with simple steatosis, and 30 controls. Serum glyceraldehyde-derived AGE levels (U/mL) were significantly elevated in NASH patients (9.78 +/- 3.73) compared with simple steatosis (7.17 +/- 2.28, P = 0.018) or healthy controls (6.96 +/- 2.36, P = 0.003). Moreover, these were inversely correlated with adiponectin, an adipocytokine with insulin-sensitizing and anti-inflammatory properties. In addition, immunohistochemistry of glyceraldehyde-derived AGE showed intense staining in the livers of NASH patients. The present data suggest that the sustained increase of glyceraldehyde-derived AGE could at least in part contribute to the pathogenesis of NASH. The serum glyceraldehyde-derived AGE level may be a useful biomarker for discriminating NASH from simple steatosis.