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BACKGROUND: Biomarkers for metabolic dysfunction-associated steatohepatitis (MASH) have been considered based on proteomic and lipidomic data from plasma and liver tissue without clinical benefits. This study evaluated proteomics-based plasma and liver tissue biomarkers collected simultaneously from patients with metabolic dysfunction-associated steatotic liver disease (MASLD). METHODS: Liver tissue and plasma samples were collected during liver biopsy to diagnose MASLD. Untargeted proteomics was performed on 64 patients. RESULTS: Twenty plasma proteins were up- or downregulated in patients with MASH compared with those without MASH. The potential biomarkers utilizing the best combinations of these plasma proteins had an area under the receiver operating curve (AUROC) of 0.671 for detecting those with MASH compared with those without it. However, none of the 20 plasma proteins were represented among the significantly regulated liver tissue proteins in patients with MASH. Ten of them displayed a trend and relevance in liver tissue with MASLD progression. These 10 plasma proteins had an AUROC of 0.793 for MASH identification and higher positive and negative predictive values. CONCLUSION: The plasma and liver protein expressions of patients with MASH were not directly comparable. Plasma protein biomarkers that are also expressed in liver tissue can help improve MASH detection.

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BACKGROUND: Diabetes and obesity are associated with altered lipid metabolism and hepatic steatosis. Studies suggest that increases in lipid accumulation in these patients with metabolic dysfunction-associated steatotic liver disease (MASLD) are not uniform for all lipid components. This study evaluates this variation. METHODS: A comprehensive lipidomic analysis of different lipid groups, were performed on liver tissue and plasma samples obtained at the time of histology from a well-defined cohort of 72 MASLD participants. The lipid profiles of controls were compared to those of MASLD patients with obesity, diabetes, or a combination of both. RESULTS: MASLD patients without obesity or diabetes exhibited distinct changes in the lipid profile of their liver tissue. The presence of diabetes or obesity further modified these lipid profiles (e.g., ceramide 47:7;4O), with positive or negative correlation (p < 0.05). A step-wise increase (long-chain fatty acids, triglycerides, and ceramides) or decrease (ultra-long fatty acids, diglycerides, and phospholipids) for lipid groups was observed compared to control among patients with MASLD without obesity or diabetes to MASLD patients with obesity as a single risk factor, and MASLD patients with obesity and diabetes. Changes in lipids observed in the plasma did not align with their corresponding liver tissue findings. CONCLUSION: The changes observed in the composition of lipids are not similar in patients with obesity and diabetes among those with MASLD. This highlights the different metabolic processes at play. The presence of obesity or diabetes in patients with MASLD exacerbates these lipid derangements, underscoring the potential for targeted intervention in MASLD patients.

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BACKGROUND: The prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing in the USA. Some of these patients develop non-alcoholic steatohepatitis (NASH), which can progress to cirrhosis. Ultrasound imaging is one of the most used modalities for diagnosing hepatic steatosis. Primary care providers are increasingly using point-of-care ultrasound (POCUS), which could increase the number of subjects diagnosed with NAFLD. This study evaluates the accuracy of POCUS in identifying patients with NASH. METHODS: Patients with hepatic steatosis without excess alcohol intake or other liver diseases undergoing liver biopsy were included in this study. These patients underwent POCUS and vibration-controlled transient elastography (VCTE) evaluations within 3 months of a liver biopsy. A comparison of POCUS data with liver histology and VCTE were made to assess the validity of POCUS evaluation in diagnosing NAFLD and NASH. RESULTS: The steatosis score from the liver histology had a low correlation with the controlled attenuation parameter score from VCTE ( r  = 0.27) and a moderate correlation with the grade of steatosis detected by the POCUS exam ( r  = 0.57). The NAFLD activity score on histology was found to correlate with the ultrasonographic fatty liver index (USFLI) from the POCUS exam ( r  = 0.59). A USFLI ≥ 6 diagnosed NASH with a sensitivity of 81%, and a value of ≤3 ruled out the diagnosis of NASH with a sensitivity of 100%. CONCLUSION: The provider can use the POCUS exam in clinical practice to diagnose NAFLD and reliably stratify patients who have NASH.

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BACKGROUND AIMS: Prolonged systemic inflammation contributes to poor clinical outcomes in severe alcohol-associated hepatitis (AH) even after the cessation of alcohol use. However, mechanisms leading to this persistent inflammation remain to be understood. APPROACH RESULTS: We show that while chronic alcohol induces nucleotide-binding oligomerization domain-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome activation in the liver, alcohol binge results not only in NLRP3 inflammasome activation but also in increased circulating extracellular apoptosis-associated speck-like protein containing a caspase recruitment domain (ex-ASC) specks and hepatic ASC aggregates both in patients with AH and in mouse models of AH. These ex-ASC specks persist in circulation even after the cessation of alcohol use. Administration of alcohol-induced-ex-ASC specks in vivo in alcohol-naive mice results in sustained inflammation in the liver and circulation and causes liver damage. Consistent with the key role of ex-ASC specks in mediating liver injury and inflammation, alcohol binge failed to induce liver damage or IL-1ß release in ASC-deficient mice. Our data show that alcohol induces ex-ASC specks in liver macrophages and hepatocytes, and these ex-ASC specks can trigger IL-1ß release in alcohol-naive monocytes, a process that can be prevented by the NLRP3 inhibitor, MCC950. In vivo administration of MCC950 reduced hepatic and ex-ASC specks, caspase-1 activation, IL-1ß production, and steatohepatitis in a murine model of AH. CONCLUSIONS: Our study demonstrates the central role of NLRP3 and ASC in alcohol-induced liver inflammation and unravels the critical role of ex-ASC specks in the propagation of systemic and liver inflammation in AH. Our data also identify NLRP3 as a potential therapeutic target in AH.

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BACKGROUND AND AIMS: Mixed lineage kinase domain-like pseudokinase (MLKL), a key terminal effector of necroptosis, also plays a role in intracellular vesicle trafficking that is critical for regulating liver inflammation and injury in alcohol-associated liver disease (ALD). Although receptor interacting protein kinase 3 (Rip3)-/- mice are completely protected from ethanol-induced liver injury, Mlkl-/- mice are only partially protected. Therefore, we hypothesized that cell-specific functions of MLKL may contribute to ethanol-induced injury. APPROACH AND RESULTS: Bone marrow transplants between Mlkl-/- mice and littermates were conducted to distinguish the role of myeloid versus nonmyeloid Mlkl in the Gao-binge model of ALD. Ethanol-induced hepatic injury, steatosis, and inflammation were exacerbated in Mlkl-/- →wild-type (WT) mice, whereas Mlkl deficiency in nonmyeloid cells (WT→ Mlkl-/- ) had no effect on Gao-binge ethanol-induced injury. Importantly, Mlkl deficiency in myeloid cells exacerbated ethanol-mediated bacterial burden and accumulation of immune cells in livers. Mechanistically, challenging macrophages with lipopolysaccharide (LPS) induced signal transducer and activator of transcription 1-mediated expression and phosphorylation of MLKL, as well as translocation and oligomerization of MLKL to intracellular compartments, including phagosomes and lysosomes but not plasma membrane. Importantly, pharmacological or genetic inhibition of MLKL suppressed the phagocytic capability of primary mouse Kupffer cells (KCs) at baseline and in response to LPS with/without ethanol as well as peripheral monocytes isolated from both healthy controls and patients with alcohol-associated hepatitis. Further, in vivo studies revealed that KCs of Mlkl-/- mice phagocytosed fewer bioparticles than KCs of WT mice. CONCLUSION: Together, these data indicate that myeloid MLKL restricts ethanol-induced liver inflammation and injury by regulating hepatic immune cell homeostasis and macrophage phagocytosis.

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BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is highly prevalent and increasing in the United States. Based on patient characteristics and biochemical profiles, predictive indices have been formulated to evaluate the presence and severity of NAFLD. This study evaluates the accuracy of these indices versus vibration-controlled transient elastography (VCTE™) to screen at-risk populations for NAFLD. METHODS: Subjects from the NHANES datasets (2017-2018) without other liver diseases with completed VCTE™ data were studied (n = 5062). Hepatic steatosis and fibrosis scores were calculated and compared with controlled attenuation parameter (CAP) and elastography measurements of VCTE™, respectively. RESULTS: The prevalence of NAFLD was 58.5%. Against a CAP cut-off value of ≥238 dB/m for diagnosing fatty liver, the US fatty liver index [US-FLI] had the highest positive predictive value (90%) and specificity (63.7%). The coefficient of correlation against CAP was strong for fatty liver index [FLI] (r = 0.645) and US-FLI (r = 0.608). The hepatic steatosis index [HSI] had the highest negative predictive value (82.1%) and sensitivity (75%) for ruling out steatosis. HSI and FLI, which use commonly obtained clinical parameters, had a high diagnostic odds ratios (21.2 and 18.6, respectively) compared to US-FLI (4.97), which requires insulin levels in the calculation. These findings were similar across all ethnicities studied. CONCLUSION: US-FLI is a reliable scoring system to diagnose patients with fatty liver. HSI and FLI are more easily calculated and can be used in clinical practices to diagnose NAFLD in at-risk populations.

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BACKGROUND AND AIMS: Patients with severe alcohol-associated hepatitis (AH) have high mortality. Corticosteroids improve survival only for 30 days. We targeted inflammation, cellular injury, and gut leakiness in a randomized clinical trial comparing combination therapy to corticosteroids on 180-day survival. APPROACH AND RESULTS: Subjects with a clinical diagnosis of severe AH (Model for End-Stage Liver Disease [MELD] >20, Maddrey discriminant function [MDF] >32) were randomized to receive methylprednisolone (PRED; 28 days) or a combination of anakinra (14 days) plus pentoxifylline (28 days) plus zinc (COMB; 180 days). The primary endpoint was survival at 180 days. The study was designed in 2013, initiated in October 2014, and completed in March 2018. Five hundred patients were screened to randomize 104 subjects with a clinical diagnosis of AH with a MELD score >20. Fifty-three patients were randomized into the COMB and 50 to the PRED treatment; 1 dropped out of the study before randomization. Mean age was 45.3 ± 10.4 years; 60.6% were males, 92.3% White, and mean MELD 25.7 ± 3.9. Kaplan-Meier survival estimate at 180 days was 67.9% in COMB and 56% in PRED (HR = 0.69; p = 0.3001). Survival curves separated by 90 days (COMB, 69.8%; PRED, 58.0%; HR = 0.69; p = 0.28). Survival at 28 days was similar between the COMB (83.4%) and PRED groups (81.2%; HR = 0.91; p = 0.85). There were no unexpected serious adverse events, and incidence of infection was comparable between groups. MELD 20-25 and MELD >26 strata showed nonsignificant treatment effects in favor of COMB. CONCLUSIONS: A combination of anakinra, pentoxifylline plus zinc provides similar survival benefits compared to corticosteroid therapy in severe AH.

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There is mounting evidence that microbes residing in the human intestine contribute to diverse alcohol-associated liver diseases (ALD) including the most deadly form known as alcohol-associated hepatitis (AH). However, mechanisms by which gut microbes synergize with excessive alcohol intake to promote liver injury are poorly understood. Furthermore, whether drugs that selectively target gut microbial metabolism can improve ALD has never been tested. We used liquid chromatography tandem mass spectrometry to quantify the levels of microbe and host choline co-metabolites in healthy controls and AH patients, finding elevated levels of the microbial metabolite trimethylamine (TMA) in AH. In subsequent studies, we treated mice with non-lethal bacterial choline TMA lyase (CutC/D) inhibitors to blunt gut microbe-dependent production of TMA in the context of chronic ethanol administration. Indices of liver injury were quantified by complementary RNA sequencing, biochemical, and histological approaches. In addition, we examined the impact of ethanol consumption and TMA lyase inhibition on gut microbiome structure via 16S rRNA sequencing. We show the gut microbial choline metabolite TMA is elevated in AH patients and correlates with reduced hepatic expression of the TMA oxygenase flavin-containing monooxygenase 3 (FMO3). Provocatively, we find that small molecule inhibition of gut microbial CutC/D activity protects mice from ethanol-induced liver injury. CutC/D inhibitor-driven improvement in ethanol-induced liver injury is associated with distinct reorganization of the gut microbiome and host liver transcriptome. The microbial metabolite TMA is elevated in patients with AH, and inhibition of TMA production from gut microbes can protect mice from ethanol-induced liver injury.

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IMPORTANCE: No therapy has been shown to reduce the risk of serious adverse outcomes in patients with nonalcoholic steatohepatitis (NASH). OBJECTIVE: To investigate the long-term relationship between bariatric surgery and incident major adverse liver outcomes and major adverse cardiovascular events (MACE) in patients with obesity and biopsy-proven fibrotic NASH without cirrhosis. DESIGN, SETTING, AND PARTICIPANTS: In the SPLENDOR (Surgical Procedures and Long-term Effectiveness in NASH Disease and Obesity Risk) study, of 25 828 liver biopsies performed at a US health system between 2004 and 2016, 1158 adult patients with obesity were identified who fulfilled enrollment criteria, including confirmed histological diagnosis of NASH and presence of liver fibrosis (histological stages 1-3). Baseline clinical characteristics, histological disease activity, and fibrosis stage of patients who underwent simultaneous liver biopsy at the time of bariatric surgery were balanced with a nonsurgical control group using overlap weighting methods. Follow-up ended in March 2021. EXPOSURES: Bariatric surgery (Roux-en-Y gastric bypass, sleeve gastrectomy) vs nonsurgical care. MAIN OUTCOMES AND MEASURES: The primary outcomes were the incidence of major adverse liver outcomes (progression to clinical or histological cirrhosis, development of hepatocellular carcinoma, liver transplantation, or liver-related mortality) and MACE (a composite of coronary artery events, cerebrovascular events, heart failure, or cardiovascular death), estimated using the Firth penalized method in a multivariable-adjusted Cox regression analysis framework. RESULTS: A total of 1158 patients (740 [63.9%] women; median age, 49.8 years [IQR, 40.9-57.9 years], median body mass index, 44.1 [IQR, 39.4-51.4]), including 650 patients who underwent bariatric surgery and 508 patients in the nonsurgical control group, with a median follow-up of 7 years (IQR, 4-10 years) were analyzed. Distribution of baseline covariates, including histological severity of liver injury, was well-balanced after overlap weighting. At the end of the study period in the unweighted data set, 5 patients in the bariatric surgery group and 40 patients in the nonsurgical control group experienced major adverse liver outcomes, and 39 patients in the bariatric surgery group and 60 patients in the nonsurgical group experienced MACE. Among the patients analyzed with overlap weighting methods, the cumulative incidence of major adverse liver outcomes at 10 years was 2.3% (95% CI, 0%-4.6%) in the bariatric surgery group and 9.6% (95% CI, 6.1%-12.9%) in the nonsurgical group (adjusted absolute risk difference, 12.4% [95% CI, 5.7%-19.7%]; adjusted hazard ratio, 0.12 [95% CI, 0.02-0.63]; P = .01). The cumulative incidence of MACE at 10 years was 8.5% (95% CI, 5.5%-11.4%) in the bariatric surgery group and 15.7% (95% CI, 11.3%-19.8%) in the nonsurgical group (adjusted absolute risk difference, 13.9% [95% CI, 5.9%-21.9%]; adjusted hazard ratio, 0.30 [95% CI, 0.12-0.72]; P = .007). Within the first year after bariatric surgery, 4 patients (0.6%) died from surgical complications, including gastrointestinal leak (n = 2) and respiratory failure (n = 2). CONCLUSIONS AND RELEVANCE: Among patients with NASH and obesity, bariatric surgery, compared with nonsurgical management, was associated with a significantly lower risk of incident major adverse liver outcomes and MACE.

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Hepatocellular death contributes to progression of alcohol-associated (ALD-associated) and non-alcohol-associated (NAFL/NASH) liver diseases. However, receptor-interaction protein kinase 3 (RIP3), an intermediate in necroptotic cell death, contributes to injury in murine models of ALD but not NAFL/NASH. We show here that a differential role for mixed-lineage kinase domain-like protein (MLKL), the downstream effector of RIP3, in murine models of ALD versus NAFL/NASH and that RIP1-RIP3-MLKL can be used as biomarkers to distinguish alcohol-associated hepatitis (AH) from NASH. Phospho-MLKL was higher in livers of patients with NASH compared with AH or healthy controls (HCs). MLKL expression, phosphorylation, oligomerization, and translocation to plasma membrane were induced in WT mice fed diets high in fat, fructose, and cholesterol but not in response to Gao-binge (acute on chronic) ethanol exposure. Mlkl-/- mice were not protected from ethanol-induced hepatocellular injury, which was associated with increased expression of chemokines and neutrophil recruitment. Circulating concentrations of RIP1 and RIP3, but not MLKL, distinguished patients with AH from HCs or patients with NASH. Taken together, these data indicate that MLKL is differentially activated in ALD/AH compared with NAFL/NASH in both murine models and patients. Furthermore, plasma RIP1 and RIP3 may be promising biomarkers for distinguishing AH and NASH.

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BACKGROUND AND AIMS: Given the lack of effective therapies and high mortality in acute alcohol-associated hepatitis (AH), it is important to develop rationally designed biomarkers for effective disease management. Complement, a critical component of the innate immune system, contributes to uncontrolled inflammatory responses leading to liver injury, but is also involved in hepatic regeneration. Here, we investigated whether a panel of complement proteins and activation products would provide useful biomarkers for severity of AH and aid in predicting 90-day mortality. APPROACH AND RESULTS: Plasma samples collected at time of diagnosis from 254 patients with moderate and severe AH recruited from four medical centers and 31 healthy persons were used to quantify complement proteins by enzyme-linked immunosorbent assay and Luminex arrays. Components of the classical and lectin pathways, including complement factors C2, C4b, and C4d, as well as complement factor I (CFI) and C5, were reduced in AH patients compared to healthy persons. In contrast, components of the alternative pathway, including complement factor Ba (CFBa) and factor D (CFD), were increased. Markers of complement activation were also differentially evident, with C5a increased and the soluble terminal complement complex (sC5b9) decreased in AH. Mannose-binding lectin, C4b, CFI, C5, and sC5b9 were negatively correlated with Model for End-Stage Liver Disease score, whereas CFBa and CFD were positively associated with disease severity. Lower CFI and sC5b9 were associated with increased 90-day mortality in AH. CONCLUSIONS: Taken together, these data indicate that AH is associated with a profound disruption of complement. Inclusion of complement, especially CFI and sC5b9, along with other laboratory indicators, could improve diagnostic and prognostic indications of disease severity and risk of mortality for AH patients.

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BACKGROUND/AIMS: Despite high mortality of alcohol-associated hepatitis, there has been limited advancement in treatment strategies. Defeat Alcoholic Steatohepatitis (DASH) is a multicenter, randomized, double-blind controlled trial whose primary objective was to evaluate the safety and efficacy of a novel combination of 3 drugs targeting different perturbations in AH. METHODS: Severe AH was diagnosed by liver biopsy or clinical and biochemical criteria and model for end stage liver disease (MELD) score ≥ 20 stratified by MELD scores (20-25 and ≥ 26) and randomized to a combination of an interleukin receptor 1 antagonist, Anakinra(100 mg daily for 14 days) to suppress acute inflammation, pentoxifylline (400 mg three times a day for 28 days) to prevent hepatorenal syndrome, and zinc sulfate (220 mg orally once daily for 6 months) or the standard of care therapy including methylprednisolone 32 mg orally once daily for 28 days. The primary efficacy outcome was the unadjusted log-rank test of the Kaplan-Meier survival estimates for the two treatment groups at 180 days. RESULTS: Between July 2012 to March 2018, 500 subjects with severe AH were screened of which 104 subjects were enrolled with MELD score of 25.6 ± 3.2 (20.0-35.0) in the investigational arm and 25.8 ± 4.5 (20.0-40.0) in the standard of care arm. Causes of screen failures included not meeting eligibility criteria (n = 347), declining to participate (n = 39), and other reasons (n = 10). CONCLUSIONS: Data from the DASH consortium studies will determine if a combination of drugs targeting multiple mechanisms of injury in the severe AH will improve clinical outcomes.

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Nonalcoholic fatty liver disease (NAFLD) is characterized by hepatic fat accumulation and impaired insulin sensitivity. Reduced hepatic ketogenesis may promote these pathologies, but data are inconclusive in humans and the link between NAFLD and reduced insulin sensitivity remains obscure. We investigated individuals with obesity-related NAFLD and hypothesized that ß-hydroxybutyrate (ßOHB; the predominant ketone species) would be reduced and related to hepatic fat accumulation and insulin sensitivity. Furthermore, we hypothesized that ketones would impact skeletal muscle mitochondrial respiration in vitro. Hepatic fat was assessed by 1H-MRS in 22 participants in a parallel design, case control study [Control: n = 7, age 50 ± 6 yr, body mass index (BMI) 30 ± 1 kg/m2; NAFLD: n = 15, age 57 ± 3 yr, BMI 35 ± 1 kg/m2]. Plasma assessments were conducted in the fasted state. Whole body insulin sensitivity was determined by the gold-standard hyperinsulinemic-euglycemic clamp. The effect of ketone dose (0.5-5.0 mM) on mitochondrial respiration was conducted in human skeletal muscle cell culture. Fasting ßOHB, a surrogate measure of hepatic ketogenesis, was reduced in NAFLD (-15.6%, P < 0.01) and correlated negatively with liver fat (r2 = 0.21, P = 0.03) and positively with insulin sensitivity (r2 = 0.30, P = 0.01). Skeletal muscle mitochondrial oxygen consumption increased with low-dose ketones, attributable to increases in basal respiration (135%, P < 0.05) and ATP-linked oxygen consumption (136%, P < 0.05). NAFLD pathophysiology includes impaired hepatic ketogenesis, which is associated with hepatic fat accumulation and impaired insulin sensitivity. This reduced capacity to produce ketones may be a potential link between NAFLD and NAFLD-associated reductions in whole body insulin sensitivity, whereby ketone concentrations impact skeletal muscle mitochondrial respiration.

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BACKGROUND: Current guidelines recommend surveillance for hepatocellular carcinoma (HCC) in high-risk patients. This high risk is defined by the presence of cirrhosis. However, HCC due to underlying nonalcoholic steatohepatitis (NASH), even without progressing to cirrhosis, is a rising concern. Hence, we aimed to determine the association of HCC with NASH using a large national database. METHODS: A cross-sectional study was performed using the 2012 National Inpatient Sample. The study group was all adult patients' age 18-90 years who have a diagnosis of NASH which was identified using the International Classification of Diseases 9th version (ICD-9) codes. The control group included the rest of adult individuals without discharge records of NASH. We identified the diagnosis of HCC in both study and control groups using the ICD-9 codes. We calculated the association between NASH and HCC using univariable and multivariate logistic regression. RESULTS: Totally, 30 712 524 hospitalizations were included in our study. This cohort included 218 950 patients with NASH (study group) and 30 493 574 patients without NASH (control group). The study group patients aged 57.3 ± 0.10 years (59.4% females) comparing to 54.5 ± 0.11 years (57.1% female) in the control group. HCC prevalence in subjects with NASH was 0.50% [95% confidence interval (CI): 0.41-0.59] compared to 0.21% (95% CI: 0.20-0.23) in subjects without NASH (P < 0.001). After adjusting for age, gender, smoking, alcohol use, obesity, hepatitis C virus, hepatitis B virus, hemochromatosis, HIV, cirrhosis and the modified comorbidity index, subjects with NASH were 60% more likely to have HCC than those without NASH (adjusted odds ratio: 1.6, 95% CI: 1.4-1.9, P < 0.001). CONCLUSION: Our study showed that NASH patients are 60% more likely to develop HCC compared with patients without NASH. Close monitoring and even periodical surveillance might be needed.

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PURPOSE: We aimed to determine the immediacy of exercise intervention on liver-specific metabolic processes in nonalcoholic fatty liver disease. METHODS: We undertook a short-term (7-d) exercise training study (60 min·d treadmill walking at 80%-85% of maximal heart rate) in obese adults (N = 13, 58 ± 3 yr, 34.3 ± 1.1 kg·m, >5% hepatic lipid by H-magnetic resonance spectroscopy). Insulin sensitivity index was estimated by oral glucose tolerance test using the Soonthorpun model. Hepatic insulin extraction (HIE) was calculated as the molar difference in area under the curve (AUC) for insulin and C-peptide (HIE = 1 - (AUCInsulin/AUCC-Pep)). RESULTS: The increases in HIE, V˙O2max, and insulin sensitivity index after the intervention were 9.8%, 9.8%, and 34%, respectively (all, P < 0.05). Basal fat oxidation increased (pre: 47 ± 6 mg·min vs post: 65 ± 6 mg·min, P < 0.05) and carbohydrate oxidation decreased (pre: 160 ± 20 mg·min vs post: 112 ± 15 mg·min, P < 0.05) with exercise training. After the intervention, HIE correlated positively with adiponectin (r = 0.56, P < 0.05) and negatively with TNF-α (r = -0.78, P < 0.001). CONCLUSIONS: By increasing HIE along with peripheral insulin sensitivity, aerobic exercise training rapidly reverses some of the underlying physiological mechanisms associated with nonalcoholic fatty liver disease, in a weight loss-independent manner. This reversal could potentially act through adipokine-related pathways.

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BACKGROUND AND AIMS: Sarcopenia or skeletal muscle loss adversely affects outcomes in cirrhosis. The impact of aetiology of liver disease on the severity or the rate of muscle loss is not known. METHODS: Consecutive, well-characterized adult patients with cirrhosis due to viral hepatitis (VH), alcoholic liver disease (ALD) or non-alcoholic fatty liver disease (NAFLD) and non-diseased controls with at least two temporally distinct abdominal CT (computed tomography) scans were evaluated. Psoas, paraspinal and abdominal wall muscle areas at the L3 vertebra level were quantified on the CT scans. Standardized rate of change in muscle area was expressed as change in area/100 days. Univariate and multivariable analyses were performed to identify contributors to rate of muscle loss and survival. RESULTS: Among 83 cirrhotics (NAFLD n = 26, ALD n = 39, VH n = 18), there were 20 (24.1%) deaths over 62.7 ± 41.3 months. The mean percentage change in psoas area was -0.03 ± 0.05/100d in controls and -3.52 ± 0.45/100d in cirrhosis (P < .001). The mean percentage change in psoas area was -1.72 ± 0.27/100d in NAFLD, -5.28 ± 0.86/100d in ALD and -2.29 ± 0.28/100d in VH. Among cirrhotics, patients with ALD had the lowest initial muscle area and most rapid rate of reduction in muscle area. Aetiology of liver disease, model for end-stage liver disease (MELD) and the rate of loss of muscle area were independent risk factors for survival. CONCLUSIONS: Aetiology of liver disease is an independent risk factor for sarcopenia with the greatest rate of muscle loss noted in ALD. Survival in cirrhosis was dependent on initial muscle mass, rate of muscle loss and MELD score.

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Nonalcoholic liver disease (NAFLD) is manifested with a wide spectrum of clinical symptoms and is closely associated with the metabolic syndrome, inflammation, and mitochondrial dysfunction. Although the mechanism of mitochondrial dysfunction in NAFLD is still not fully elucidated, multiple studies have demonstrated evidence of molecular, biochemical, and biophysical mitochondrial abnormalities in NAFLD. Given the association between NAFLD and mitochondrial dysfunction, the aim of this study is to analyze circulating levels of Krebs cycle intermediates in a cohort of NAFLD-affected individuals and matching healthy controls and to correlate our findings with the liver function metrics. Standard serum biochemistry and Krebs cycle intermediates were analyzed in NAFLD (n = 22) and matched control (n = 67) cohorts. Circulating levels of isocitrate and citrate were significantly (p < 0.05) elevated in the NAFLD cohort of patients. The area under the curve (AUROC) for these two metabolites exhibited a moderate clinical utility. Correlations between plasma Krebs cycle intermediates and standard clinical plasma metrics were explored by Pearson's correlation coefficient. The data obtained for plasma Krebs cycle intermediates suggest pathophysiological insights that link mitochondrial dysfunction with NAFLD. Our findings reveal that plasma isocitrate and citrate can discriminate between normal and NAFLD cohorts and can be utilized as noninvasive markers of mitochondrial dysfunction in NAFLD. Future studies with large populations at different NAFLD stages are warranted.