• NAFLD
• O-GlcNAcylation
• mitochondrial dysfunction

• GLS1
• GLS2
• NAFLD
• NASH
• TCA cycle
• VLDL
• folate cycle
• glutaminase
• methionine cycle
• phospholipids

• Adult
• Animals
• Choline
• Disease Models, Animal
• Female
• Glutaminase/metabolism
• Hepatocytes/metabolism
• Humans
• Lipid Metabolism
• Lipoproteins, VLDL/metabolism
• Liver/enzymology
• Male
• Methionine
• Mice, Inbred C57BL
• Non-alcoholic Fatty Liver Disease/pathology
• Oxidative Stress
• Phospholipids/metabolism
• Triglycerides/metabolism

• R01 AT001576 NCCIH NIH HHS

Distinct environmental insults might interact with fructose consumption and contribute to the development of metabolic disorders. To address whether in utero glucocorticoid exposure and fructose intake modulate metabolic responses, adult female Wistar rats were exposed to dexamethasone (DEX) during pregnancy, and the offspring were administered fructose at a later time. Briefly, dams received DEX during the third period of pregnancy, while control dams remained untreated. Offspring born to control and DEX-treated mothers were defined as CTL-off and DEX-off, respectively, while untreated animals were designated CTL-off-CTL and DEX-off-CTL. CLT-off and DEX-off treated with 10% fructose in the drinking water for 8 weeks are referred to as CTL-off-FRU and DEX-off-FRU. We found that fructose promoted glucose intolerance and whole-body gluconeogenesis in both CTL-off-FRU and DEX-off-FRU animals. On the other hand, hepatic lipid accumulation was significantly stimulated in DEX-off-FRU rats when compared to the CTL-off-FRU group. The DEX-off-FRU group also displayed impaired very-low-density lipoprotein (VLDL) production and reduced hepatic expression of apoB, mttp, and sec22b. DEX-off-FRU has lower hepatic levels of autophagy markers. Taken together, our results support the unprecedented notion that in utero glucocorticoid exposure exacerbates hepatic steatosis caused by fructose consumption later in life.

• DOHaD
• fructose
• glucocorticoids
• hepatic steatosis
• pregnancy

• Animals
• Apolipoproteins B/genetics
• Apolipoproteins B/metabolism
• Carrier Proteins/genetics
• Carrier Proteins/metabolism
• Dexamethasone/toxicity
• Dietary Sugars/toxicity
• Fatty Liver/chemically induced
• Fatty Liver/genetics
• Fatty Liver/metabolism
• Fatty Liver/pathology
• Female
• Fructose/toxicity
• Gestational Age
• Gluconeogenesis/drug effects
• Lipid Metabolism/drug effects
• Lipid Metabolism/genetics
• Lipoproteins, VLDL/metabolism
• Liver/drug effects
• Liver/metabolism
• Liver/pathology
• Male
• Pregnancy
• Prenatal Exposure Delayed Effects
• R-SNARE Proteins/genetics
• R-SNARE Proteins/metabolism
• Rats, Wistar

• CYP2E1
• acetaminophen
• hepatotoxicity
• ketone body
• osteopontin

Neutrophils and macrophages are important constituents of the hepatic inflammatory infiltrate in non-alcoholic steatohepatitis. These innate immune cells express CD18, an adhesion molecule that facilitates leukocyte activation. In the context of fatty liver, activation of infiltrated leukocytes is believed to enhance hepatocellular injury. The objective of this study was to determine the degree to which activated innate immune cells promote steatohepatitis by comparing hepatic outcomes in wild-type and CD18-mutant mice fed a methionine-choline-deficient (MCD) diet. After 3 weeks of MCD feeding, hepatocyte injury, based on serum ALT elevation, was 40% lower in CD18-mutant than wild-type mice. Leukocyte infiltration into the liver was not impaired in CD18-mutant mice, but leukocyte activation was markedly reduced, as shown by the lack of evidence of oxidant production. Despite having reduced hepatocellular injury, CD18-mutant mice developed significantly more hepatic steatosis than wild-type mice after MCD feeding. This coincided with greater hepatic induction of pro-inflammatory and lipogenic genes as well as a modest reduction in hepatic expression of adipose triglyceride lipase. Overall, the data indicate that CD18 deficiency curbs MCD-mediated liver injury by limiting the activation of innate immune cells in the liver without compromising intrahepatic cytokine activation. Reduced liver injury occurs at the expense of increased hepatic steatosis, which suggests that in addition to damaging hepatocytes, infiltrating leukocytes may influence lipid homeostasis in the liver.

• Adipose Tissue/metabolism
• Animals
• CD18 Antigens/genetics
• CD18 Antigens/physiology
• Choline/chemistry
• Cytokines/metabolism
• Disease Models, Animal
• Fatty Liver/metabolism
• Hepatocytes/cytology
• Immunity, Innate
• Inflammation
• Leukocytes/cytology
• Leukocytes/metabolism
• Lipase/metabolism
• Liver/metabolism
• Male
• Methionine/chemistry
• Mice
• Mice, Inbred C57BL
• Mutation
• Oxygen/chemistry
• Peroxidase/metabolism
• Triglycerides/metabolism

• K08 DK098270 NIDDK NIH HHS
• P30 CA082103 NCI NIH HHS
• T32 DK060414 NIDDK NIH HHS
• R01 DK093646 NIDDK NIH HHS
• R56 DK088674 NIDDK NIH HHS
• R01 DK068450 NIDDK NIH HHS
• R21 DK068414 NIDDK NIH HHS
• P30 DK026743 NIDDK NIH HHS
• National Institute of Diabetes and Digestive and Kidney Diseases
• National Cancer Institute

To investigate the pathological changes in the process of alcoholic liver injury.

Thirty healthy male Kunming mice were randomly divided into a control group (n = 10) and a model group (n = 20). The control group was executed to take the liver tissue at 0 wk. The model group was treated with alcohol of 56 degrees (0.15 ml/20 g•d) for 8 wk, and then executed to take the liver tissue at four and 8 wk. The expression changes of lipid droplets during alcoholic liver injury were assessed by hematoxylin and eosin staining and oil red O staining. The integral optical density of histology samples was analyzed with Image-ProPlus6.0 software.

The content of lipid drops began to increase at 4 wk (20.29 ± 7.07 vs 8.06 ± 2.06, P < 0.01), and significantly increased at 8 wk (34.88 ± 15.33 vs 8.06 ± 2.06, P < 0.01). Compared to that at 4 wk, the amount of expression of lipid droplets showed a rising trend at 8 wk (34.88 ± 15.33 vs 20.29 ± 7.07, P < 0.05).

The levels of lipid droplets show a growing trend along with the aggravation of hepatic steatosis during alcoholic liver injury in mice.

• Mice
• Alcoholic liver injury
• Oil red O staining
• Hematoxylin and eosin staining

• Fatty acid uptake
• Lipid metabolism
• NAFLD
• PI3K/AKT pathway
• Quercetin

• Animals
• CCAAT-Enhancer-Binding Protein-alpha/genetics
• CCAAT-Enhancer-Binding Protein-alpha/metabolism
• Cells, Cultured
• Cyclosporine/toxicity
• Doxycycline/toxicity
• Fatty Liver/chemically induced
• Fatty Liver/metabolism
• Humans
• Male
• Mice
• Mitogen-Activated Protein Kinase 1/metabolism
• Non-alcoholic Fatty Liver Disease/etiology
• Non-alcoholic Fatty Liver Disease/metabolism
• Promoter Regions, Genetic
• Receptors, Cytoplasmic and Nuclear/genetics
• Receptors, Cytoplasmic and Nuclear/metabolism
• Signal Transduction
• Tetracycline/toxicity
• Thiazepines/toxicity
• Transcription, Genetic
• Valproic Acid/toxicity

• Meta-Analysis
• Myosin Light Chain Kinase
• Steatosis
• Tight Junctions

• R56 DK094954 NIDDK NIH HHS
• P01 DK067887 NIDDK NIH HHS
• K24 DK078772 NIDDK NIH HHS
• R01 DK061931 NIDDK NIH HHS
• R01 DK068271 NIDDK NIH HHS

AIM: To investigate over-expression of Osteopontin (OPN) pathway expression and mechanisms of action in human alcoholic liver disease (ALD), in vivo and in vitro acute alcohol models.

METHODS: OPN pathway was evaluated in livers from patients with progressive stages of human ALD and serum from drinkers with and without liver cirrhosis. In vitro stellate LX2 cells exposed to acute alcohol and in vivo in acute alcoholic steatosis mouse models were also investigated for OPN pathway expression and function. WT and OPN^-/- mice were administered an acute dose of alcohol and extent of liver injury was examined by histopathology and liver biochemistry after 16-24 h. The causative role of OPN was studied in OPN knockout animals and in vitro in stellate LX2 cells, utilizing siRNA, aptamer and neutralizing antibodies to block OPN and OPN pathway. OPN pathway expression and downstream functional consequences were measured for signaling by Western blotting, plasmin activation by spectrophotometric assays and cell migration by confocal imaging and quantitation.

RESULTS: OPN expression positively correlated with disease severity in patients with progressive stages of ALD. In vivo, associated with alcoholic steatosis, a single dose of acute alcohol significantly increased hepatic OPN mRNA and protein, and a cleaved OPN form in a dose dependent manner. OPN mRNA and secreted OPN also increased in parallel with activation of LX2 stellate cells within 4 h of a single dose of alcohol. Expression of OPN receptors, αvβ3-integrin and CD44, increased in human ALD, and in vivo and in vitro with alcohol administration. This was accompanied by downstream phosphorylation of Akt and Erk, increased mRNA expression of several fibrogenesis, fibrinolysis and extracellular matrix pathway genes, plasmin activation and hepatic stellate cell (HSC) migration. Inhibition of OPN and OPN-receptor mediated signaling partially inhibited alcohol-induced HSC activation, plasmin activity and cell migration.

CONCLUSION: OPN is a key mediator of the alcohol-induced effects on hepatic stellate cell functions and liver fibrogenesis.

• Hepatic stellate cells
• Liver cirrhosis
• Plasmin
• Steatosis
• Fibrogenesis
• Transforming growth factor β
• Osteopontin isoform

• Animals
• Case-Control Studies
• Cell Movement
• Cells, Cultured
• Disease Models, Animal
• Extracellular Matrix/metabolism
• Extracellular Signal-Regulated MAP Kinases/metabolism
• Fatty Liver, Alcoholic/genetics
• Fatty Liver, Alcoholic/metabolism
• Fatty Liver, Alcoholic/pathology
• Female
• Fibrinolysin/metabolism
• Fibrinolysis
• Hepatic Stellate Cells/metabolism
• Hepatic Stellate Cells/pathology
• Humans
• Hyaluronan Receptors/metabolism
• Integrin alphaVbeta3/metabolism
• Liver Cirrhosis, Alcoholic/genetics
• Liver Cirrhosis, Alcoholic/metabolism
• Liver Cirrhosis, Alcoholic/pathology
• Mice, Inbred C57BL
• Mice, Knockout
• Osteopontin/deficiency
• Osteopontin/genetics
• Osteopontin/metabolism
• Phosphorylation
• Proto-Oncogene Proteins c-akt/metabolism
• RNA Interference
• RNA, Messenger/metabolism
• Severity of Illness Index
• Signal Transduction
• Time Factors
• Transfection
• Up-Regulation

Alcoholic liver disease is a major health problem in the United States and worldwide. Chronic alcohol consumption can cause steatosis, inflammation, fibrosis, cirrhosis and even liver cancer. Significant progress has been made to understand key events and molecular players for the onset and progression of alcoholic liver disease from both experimental and clinical alcohol studies. No successful treatments are currently available for treating alcoholic liver disease; therefore, development of novel pathophysiological-targeted therapies is urgently needed. This review summarizes the recent progress on animal models used to study alcoholic liver disease and the detrimental factors that contribute to alcoholic liver disease pathogenesis including miRNAs, S-adenosylmethionine, Zinc deficiency, cytosolic lipin-1β, IRF3-mediated apoptosis, RIP3-mediated necrosis and hepcidin. In addition, we summarize emerging adaptive protective effects induced by alcohol to attenuate alcohol-induced liver pathogenesis including FoxO3, IL-22, autophagy and nuclear lipin-1α.

• Alcoholic liver disease
• Autophagy
• Fatty liver
• Lipin-1
• FoxO3
• RIP3
• IL-22

• Animals
• Disease Models, Animal
• Drug Design
• Genetic Predisposition to Disease
• Humans
• Liver/drug effects
• Liver/metabolism
• Liver/pathology
• Liver Diseases, Alcoholic/diagnosis
• Liver Diseases, Alcoholic/drug therapy
• Liver Diseases, Alcoholic/genetics
• Liver Diseases, Alcoholic/metabolism
• Molecular Targeted Therapy
• Phenotype
• Protective Factors
• Risk Factors
• Signal Transduction/drug effects
• Treatment Outcome

Osteopontin (OPN) is a multifunctional protein involved in hepatic steatosis, inflammation, fibrosis and cancer progression. However, its role in hepatic injury induced by ischemia–reperfusion (I–R) has not yet been investigated. We show here that hepatic warm ischemia for 45 min followed by reperfusion for 4 h induced the upregulation of the hepatic and systemic level of OPN in mice. Plasma aspartate aminotransferase and alanine aminotransferase levels were strongly increased in Opn^−/− mice compared with wild-type (Wt) mice after I–R, and histological analysis of the liver revealed a significantly higher incidence of necrosis of hepatocytes. In addition, the expression levels of inducible nitric oxide synthase (iNOS), tumor necrosis factor-α (TNFα), interleukin 6 (IL6) and interferon-γ were strongly upregulated in Opn^−/− mice versus Wt mice after I–R. One explanation for these responses could be the vulnerability of the OPN-deficient hepatocyte. Indeed, the downregulation of OPN in primary and AML12 hepatocytes decreased cell viability in the basal state and sensitized AML12 hepatocytes to cell death induced by oxygen–glucose deprivation and TNFα. Further, the downregulation of OPN in AML12 hepatocytes caused a strong decrease in the expression of anti-apoptotic Bcl2 and in the ATP level. The hepatic expression of Bcl2 also decreased in Opn^−/− mice versus Wt mice livers after I–R. Another explanation could be the regulation of the macrophage activity by OPN. In RAW macrophages, the downregulation of OPN enhanced iNOS expression in the basal state and sensitized macrophages to inflammatory signals, as evaluated by the upregulation of iNOS, TNFα and IL6 in response to lipopolysaccharide. In conclusion, OPN partially protects from hepatic injury and inflammation induced in this experimental model of liver I–R. This could be due to its ability to partially prevent death of hepatocytes and to limit the production of toxic iNOS-derived NO by macrophages.

•

β-Blocker propranolol worsens liver injury in model of non-alcoholic steatohepatitis.

Prazosin an α1-adrenoceptor (AR) antagonist has been shown to reduce liver injury in a mouse model of non-alcoholic steatohepatitis (NASH) and is suggested as a potential treatment of NASH especially given its concomitant anti-fibrotic properties. The effect however, of β-AR blockade in non-cirrhotic NASH is unknown and is as such investigated here. In the presence of the β-blocker propranolol (PRL), mice fed normal chow or a half methionine and choline deficient diet, supplemented with ethionine (HMCDE), to induce NASH, showed significantly enhanced liver injury, as evidenced by higher hepatic necrosis scores and elevated serum aminotransferases (ALT). Mechanistically, we showed that murine hepatocytes express α and β adrenoceptors; that PRL directly induces hepatocyte injury and death as evidenced by increased release of lactate dehydrogenase, FASL and TNF-α from hepatocytes in the presence of PRL; and that PRL activated the apoptotic pathway in primary hepatocyte cultures, as indicated by upregulation of Fas receptor and caspase-8 proteins. The β-AR antagonist PRL therefore appears to enhance liver injury through induction of hepatocyte death via the death pathway. Further studies are now required to extrapolate these findings to humans but meanwhile, β-AR antagonists should be avoided or used with caution in patients with non-cirrhotic NASH as they may worsen liver injury.

• Apoptosis
• HPC
• Hepatocytes
• NAFLD
• NASH
• Non-alcoholic fatty liver disease
• OC
• PRL
• PRZ
• Propranolol
• Sympathetic nervous system
• hepatic progenitor cell
• non-alcoholic fatty liver disease
• non-alcoholic steatohepatitis
• oval cell
• prazosin
• propranolol

• glp
• akt
• pdk-1
• pkcζ
• steatosis
• gpcr

• 3-Phosphoinositide-Dependent Protein Kinases
• Exenatide
• Fatty Liver/physiopathology
• Fatty Liver/prevention & control
• Glucagon-Like Peptide 1/physiology
• Glucagon-Like Peptide-1 Receptor
• Hepatocytes/metabolism
• Humans
• Insulin/physiology
• Peptides/pharmacology
• Protein Kinase C/metabolism
• Protein Serine-Threonine Kinases/metabolism
• Proto-Oncogene Proteins c-akt/metabolism
• Receptors, Glucagon/metabolism
• Signal Transduction/drug effects
• Venoms/pharmacology

• P30 A1050409 PHS HHS
• R01 DK 075397 NIDDK NIH HHS
• R01 DK075397-03 NIDDK NIH HHS
• R24 DK064399-07 NIDDK NIH HHS
• R01 DK075397-01A1 NIDDK NIH HHS
• K01 DK077137-05 NIDDK NIH HHS
• R01 DK062092-01A1 NIDDK NIH HHS
• RR 00165 NCRR NIH HHS
• P51 RR000165 NCRR NIH HHS
• R01 DK062092-07 NIDDK NIH HHS
• A1070101 PHS HHS
• R03 DK089130 NIDDK NIH HHS
• R03 DK089130-03 NIDDK NIH HHS
• K01 DK077137 NIDDK NIH HHS
• R24 DK064399 NIDDK NIH HHS
• K01 DK076742 NIDDK NIH HHS
• R01 DK062092 NIDDK NIH HHS
• R01 DK075397 NIDDK NIH HHS