Deficiency of miR-208a Exacerbates CCl-Induced Acute Liver Injury in Mice by Activating Cell Death Pathways.

Acute liver injury (ALI) is associated with multiple cellular events such as necrosis, apoptosis, oxidative stress and inflammation, which can lead to liver failure. In this study, we demonstrate a new role of microRNA (miR)-208a in ALI. ALI was induced in wild-type (WT) and miR-208a knockout (KO) mice by CCl administration.

Dysregulated Autophagy and Lysosome Function Are Linked to Exosome Production by Micro-RNA 155 in Alcoholic Liver Disease.

Cellular homeostais, that is normally maintained through autophagy, is disrupted in alcoholic liver disease (ALD). Because autophagy and exosome biogenesis share common elements, we hypothesized that increased exosome production in ALD may be linked to disruption of autophagic function. We found impaired autophagy both in ALD and alcoholic hepatitis (AH) mouse models and human livers with ALD as indicated by increased hepatic p62 and LC3-II levels.

Biomarkers of Macrophage Activation and Immune Danger Signals Predict Clinical Outcomes in Alcoholic Hepatitis.

Although mortality due to acute alcoholic hepatitis (AH) correlates with Model for End-Stage Liver Disease (MELD) scores, biomarkers are critically needed to manage this disease. Increases in inflammatory markers and macrophage activation are associated with acute AH and could be potential biomarkers of clinical events and/or mortality. We enrolled 89 clinically diagnosed AH patients in four US academic medical centers.

FXR and TGR5 Agonists Ameliorate Liver Injury, Steatosis, and Inflammation After Binge or Prolonged Alcohol Feeding in Mice.

Bile acids (BAs) activate various dedicated receptors, including the farnesoid X receptor (FXR) and the Takeda G protein-coupled receptor 5 (TGR5). The FXR agonist obeticholic acid (OCA) is licensed for the treatment of primary biliary cholangitis and has shown promising results in NASH patients, whereas TGR5 agonists target inflammation and metabolism. We hypothesized that FXR and/or TGR5 agonists may be therapeutic in early alcoholic liver disease (ALD) in mice, in which hepatic inflammation plays a major role.

Macrophage-Specific Hypoxia-Inducible Factor-1α Contributes to Impaired Autophagic Flux in Nonalcoholic Steatohepatitis.

Inflammatory cell activation drives diverse cellular programming during hepatic diseases. Hypoxia-inducible factors (HIFs) have recently been identified as important regulators of immunity and inflammation. In nonalcoholic steatohepatitis (NASH), HIF-1α is upregulated in hepatocytes, where it induces steatosis; however, the role of HIF-1α in macrophages under metabolic stress has not been explored.

MicroRNA 122, Regulated by GRLH2, Protects Livers of Mice and Patients From Ethanol-Induced Liver Disease.

Background & Aims: Chronic, excessive alcohol consumption leads to alcoholic liver disease (ALD) characterized by steatosis, inflammation, and eventually cirrhosis. The hepatocyte specific microRNA 122 (MIR122) regulates hepatocyte differentiation and metabolism. We investigated whether an alcohol-induced decrease in level of MIR122 contributes to development of ALD.

Alcohol-induced miR-155 and HDAC11 inhibit negative regulators of the TLR4 pathway and lead to increased LPS responsiveness of Kupffer cells in alcoholic liver disease.

Inflammation promotes the progression of alcoholic liver disease. Alcohol sensitizes KCs to gut-derived endotoxin (LPS); however, signaling pathways that perpetuate inflammation in alcoholic liver disease are only partially understood. We found that chronic alcohol feeding in mice induced miR-155, an inflammatory miRNA in isolated KCs.

Correction: Alcohol-related changes in the intestinal microbiome influence neutrophil infiltration, inflammation and steatosis in early alcoholic hepatitis in mice.

[This corrects the article DOI: 10.1371/journal.pone.

Interleukin-1 inhibition facilitates recovery from liver injury and promotes regeneration of hepatocytes in alcoholic hepatitis in mice.

Background & Aims: Inflammation and impaired hepatocyte regeneration contribute to liver failure in alcoholic hepatitis (AH). Interleukin (IL)-1 is a key inflammatory cytokine in the pathobiology of AH. The role of IL-1 in liver regeneration in the recovery phase of alcohol-induced liver injury is unknown.

Circulating and Exosome-Packaged Hepatitis C Single-Stranded RNA Induce Monocyte Differentiation via TLR7/8 to Polarized Macrophages and Fibrocytes.

Monocytes and macrophages (MΦs) play a central role in the pathogenesis of chronic hepatitis C virus (HCV) infection. The tissue microenvironment triggers monocyte differentiation into MΦs, with polarization ranging within the spectrum of M1 (classical) to M2 (alternative) activation. Recently, we demonstrated that HCV infection leads to monocyte differentiation into polarized MΦs that mediate stellate cell activation via TGF-β.

Hepatitis C Virus-Induced Monocyte Differentiation Into Polarized M2 Macrophages Promotes Stellate Cell Activation via TGF-β.

Background & Aims: Monocyte and macrophage (MΦ) activation contributes to the pathogenesis of chronic hepatitis C virus (HCV) infection. Disease pathogenesis is regulated by both liver-resident MΦs and monocytes recruited as precursors of MΦs into the damaged liver. Monocytes differentiate into M1 (classic/proinflammatory) or M2 (alternative/anti-inflammatory) polarized MΦs in response to tissue microenvironment.

Inhibition of spleen tyrosine kinase activation ameliorates inflammation, cell death, and steatosis in alcoholic liver disease.

Unlabelled: The spectrum of alcoholic liver disease (ALD) is a major cause of mortality with limited therapies available. Because alcohol targets numerous signaling pathways in hepatocytes and in immune cells, the identification of a master regulatory target that modulates multiple signaling processes is attractive. In this report, we assessed the role of spleen tyrosine kinase (SYK), a nonreceptor tyrosine kinase, which has a central modulatory role in multiple proinflammatory signaling pathways involved in the pathomechanism of ALD.

Therapeutic Benefits of Spleen Tyrosine Kinase Inhibitor Administration on Binge Drinking-Induced Alcoholic Liver Injury, Steatosis, and Inflammation in Mice.

Background: Binge drinking is increasingly recognized as an important cause of liver disease with limited therapeutic options for patients. Binge alcohol use, similar to chronic alcohol consumption, induces numerous deregulated signaling events that drive liver damage, steatosis, and inflammation. In this article, we evaluated the role of spleen tyrosine kinase (SYK), which modulates numerous signaling events previously identified linked in the development alcohol-induced liver pathology.

The pro-inflammatory effects of miR-155 promote liver fibrosis and alcohol-induced steatohepatitis.

Background & Aims: Alcoholic liver disease (ALD) ranges from fatty liver to inflammation and cirrhosis. miRNA-155 is an important regulator of inflammation. In this study, we describe the in vivo role of miR-155 in ALD.

MicroRNA-155 Deficiency Attenuates Liver Steatosis and Fibrosis without Reducing Inflammation in a Mouse Model of Steatohepatitis.

Background & Aim: MicroRNAs (miRs) regulate hepatic steatosis, inflammation and fibrosis. Fibrosis is the consequence of chronic tissue damage and inflammation. We hypothesized that deficiency of miR-155, a master regulator of inflammation, attenuates steatohepatitis and fibrosis.