Life Sciences Commons^™

Inhibition Of Triggering Receptor Expressed On Myeloid Cells 1 Ameliorates Inflammation And Macrophage And Neutrophil Activation In Alcoholic Liver Disease In Mice, David Tornai, Istvan Furi, Zu T. Shen, Alexander B. Sigalov, Sahin Coban, Gyongyi Szabo

Gyongyi Szabo

Alcoholic liver disease (ALD) is characterized by macrophage and neutrophil leukocyte recruitment and activation in the liver. Damage- and pathogen-associated molecular patterns contribute to a self-perpetuating proinflammatory state in ALD. Triggering receptor expressed on myeloid cells 1 (TREM-1) is a surface receptor that amplifies inflammation induced by toll-like receptors (TLRs) and is expressed on neutrophils and monocytes/macrophages. We hypothesized that TREM-1 signaling contributes to proinflammatory pathway activation in ALD. Using an in vivo ALD model in mice, we tested the effects of ligand-independent TREM-1 inhibitory peptides that were formulated into human high-density lipoprotein (HDL)-mimicking complexes GF9-HDL and GA/E31-HDL. As revealed …

Hepatitis C Virus-Induced Monocyte Differentiation Into Polarized M2 Macrophages Promotes Stellate Cell Activation Via Tgf-Beta, Banishree Saha, Karen Kodys, Gyongyi Szabo

Gyongyi Szabo

BACKGROUND and AIMS: Monocyte and macrophage (MPhi) activation contributes to the pathogenesis of chronic hepatitis C virus (HCV) infection. Disease pathogenesis is regulated by both liver-resident MPhis and monocytes recruited as precursors of MPhis into the damaged liver. Monocytes differentiate into M1 (classic/proinflammatory) or M2 (alternative/anti-inflammatory) polarized MPhis in response to tissue microenvironment. We hypothesized that HCV-infected hepatoma cells (infected with Japanese fulminant hepatitis-1 [Huh7.5/JFH-1]) induce monocyte differentiation into polarized MPhis. METHODS: Healthy human monocytes were co-cultured with Huh7.5/JFH-1 cells or cell-free virus for 7 days and analyzed for MPhi markers and cytokine levels. A similar analysis was performed on …

Alcoholic Hepatitis Accelerates Early Hepatobiliary Cancer By Increasing Stemness And Mir-122-Mediated Hif-1alpha Activation, Aditya Ambade, Abhishek Satishchandran, Gyongyi Szabo

Gyongyi Szabo

Alcohol-related hepatocellular carcinoma (HCC) develops with advanced alcoholic liver disease and liver fibrosis. Using adult mice, we evaluate the effect of alcoholic steatohepatitis on early hepatobiliary carcinoma after initiation by diethyl-nitrosamine (DEN). Here we show that alcohol-fed DEN-injected mice have higher ALT and liver-to-body weight ratio compared to pair-fed DEN-injected mice. Alcohol feeding results in steatohepatitis indicated by increased pro-inflammatory cytokines and fibrotic genes. MRI and liver histology of alcohol+DEN mice shows hepatobiliary cysts, early hepatic neoplasia and increase in serum alpha-fetoprotein. Proliferation makers (BrdU, cyclin D1, p53) and cancer stem cell markers (CD133 and nanog) are significantly up-regulated in …

Exosomes Derived From Alcohol-Treated Hepatocytes Horizontally Transfer Liver Specific Mirna-122 And Sensitize Monocytes To Lps, Fatemeh Momen-Heravi, Shashi Bala, Karen Kodys, Gyongyi Szabo

Gyongyi Szabo

Hepatocyte damage and inflammation in monocytes/macrophages are central to the pathogenesis of alcoholic hepatitis (AH). MicroRNAs (miRNAs) regulate all of these processes. MiRNA-122 is abundantly expressed in hepatocytes while monocytes/macrophages have low levels. The role of exosomes in AH and possible cross talk between hepatocyte-derived exosomes and immune cells is not explored yet. Here, we show that the number of exosomes significantly increases in the sera of healthy individuals after alcohol binge drinking and in mice after binge or chronic alcohol consumption. Exosomes isolated from sera after alcohol consumption or from in vitro ethanol-treated hepatocytes contained miRNA-122. Exosomes derived from …

Increased Number Of Circulating Exosomes And Their Microrna Cargos Are Potential Novel Biomarkers In Alcoholic Hepatitis, Fatemeh Momen-Heravi, Banishree Saha, Karen Kodys, Donna Catalano, Abhishek Satishchandran, Gyongyi Szabo

Gyongyi Szabo

BACKGROUND: It has been well documented that alcohol and its metabolites induce injury and inflammation in the liver. However, there is no potential biomarker to monitor the extent of liver injury in alcoholic hepatitis patients. MicroRNAs (miRNAs) are a class of non-coding RNAs that are involved in various physiologic and pathologic processes. In the circulation, a great proportion of miRNAs is associated with extracellular vesicles (EVs)/exosomes. Here, we hypothesized that the exosome-associated miRNAs can be used as potential biomarkers in alcoholic hepatitis (AH).

METHODS: Exosomes were isolated from sera of alcohol-fed mice or pair-fed mice, and plasma of alcoholic hepatitis …

Progression Of Non-Alcoholic Steatosis To Steatohepatitis And Fibrosis Parallels Cumulative Accumulation Of Danger Signals That Promote Inflammation And Liver Tumors In A High Fat-Cholesterol-Sugar Diet Model In Mice, Michal Ganz, Terence N. Bukong, Timea Csak, Banishree Saha, Jin-Kyu Park, Aditya Ambade, Karen Kodys, Gyongyi Szabo

Gyongyi Szabo

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is becoming a pandemic. While multiple 'hits' have been reported to contribute to NAFLD progression to non-alcoholic steatohepatitis (NASH), fibrosis and liver cancer, understanding the natural history of the specific molecular signals leading to hepatocyte damage, inflammation and fibrosis, is hampered by the lack of suitable animal models that reproduce disease progression in humans. The purpose of this study was first, to develop a mouse model that closely mimics progressive NAFLD covering the spectrum of immune, metabolic and histopathologic abnormalities present in human disease; and second, to characterize the temporal relationship between sterile/exogenous danger …

Exosomes From Hepatitis C Infected Patients Transmit Hcv Infection And Contain Replication Competent Viral Rna In Complex With Ago2-Mir122-Hsp90, Terence N. Bukong, Fatemeh Momen-Heravi, Karen Kodys, Shashi Bala, Gyongyi Szabo

Gyongyi Szabo

Antibodies targeting receptor-mediated entry of HCV into hepatocytes confer limited therapeutic benefits. Evidence suggests that exosomes can transfer genetic materials between cells; however, their role in HCV infection remains obscure. Here, we show that exosomes isolated from sera of chronic HCV infected patients or supernatants of J6/JFH1-HCV-infected Huh7.5 cells contained HCV RNA. These exosomes could mediate viral receptor-independent transmission of HCV to hepatocytes. Negative sense HCV RNA, indicative of replication competent viral RNA, was present in exosomes of all HCV infected treatment non-responders and some treatment-naive individuals. Remarkably, HCV RNA was associated with Ago2, HSP90 and miR-122 in exosomes isolated …

Exosome-Mediated Delivery Of Rna Interference And Mirna Mimic, Fatemeh Momen-Heravi, Shashi Bala, Terence N. Bukong, Gyongyi Szabo

Gyongyi Szabo

Exosomes, membranous nanovesicles, naturally carry bio-macromolecules and play pivotal roles in both physiological intercellular crosstalk and disease pathogenesis. Here, we showed that B cell-derived exosomes can function as vehicles to deliver exogenous miRNA-155 mimic or inhibitor into hepatocytes or macrophages, respectively. Stimulation of B cells significantly increased exosome production. Unlike in parental cells, baseline level of miRNA-155 was very low in exosomes derived from stimulated B cells. Exosomes loaded with a miRNA-155 mimic significantly increased miRNA-155 levels in primary mouse hepatocytes and the liver of miRNA-155 knockout mice. Treatment of RAW macrophages with miRNA-155 inhibitor loaded exosomes resulted in statistically …

Chronic Alcohol-Induced Microrna-155 Contributes To Neuroinflammation In A Tlr4-Dependent Manner In Mice, Dora Lippai, Shashi Bala, Timea Csak, Evelyn A. Kurt-Jones, Gyongyi Szabo

Gyongyi Szabo

INTRODUCTION: Alcohol-induced neuroinflammation is mediated by pro-inflammatory cytokines and chemokines including tumor necrosis factor-alpha (TNFalpha), monocyte chemotactic protein-1 (MCP1) and interleukin-1-beta (IL-1beta). Toll-like receptor-4 (TLR4) pathway induced nuclear factor-kappaB (NF-kappaB) activation is involved in the pathogenesis of alcohol-induced neuroinflammation. Inflammation is a highly regulated process. Recent studies suggest that microRNAs (miRNAs) play crucial role in fine tuning gene expression and miR-155 is a major regulator of inflammation in immune cells after TLR stimulation. AIM: To evaluate the role of miR-155 in the pathogenesis of alcohol-induced neuroinflammation. METHODS: Wild type (WT), miR-155- and TLR4-knockout (KO) mice received 5% ethanol-containing or isocaloric …

High Fat Diet Feeding Results In Gender Specific Steatohepatitis And Inflammasome Activation, Michal Ganz, Timea Csak, Gyongyi Szabo

Gyongyi Szabo

AIM: To develop an animal model that encompasses the different facets of non-alcoholic steatohepatitis (NASH), which has been a challenge. METHODS: In this study, we used a high fat diet (HFD) feeding supplemented with fructose and sucrose in the water mimicking the high-fructose corn syrup that is abundant in the diet in the United States. We used C57Bl/6 wild-type mice for short and long-term feedings of 6 and 16 wk respectively, and evaluated the extent of liver damage, steatosis, and inflammasome activation. Our methods included histopathological analysis to assess liver damage and steatosis, which involved H and E and oil-red-o …

Sting-Irf3 Pathway Links Endoplasmic Reticulum Stress With Hepatocyte Apoptosis In Early Alcoholic Liver Disease, Jan Petrasek, Arvin Iracheta-Vellve, Timea Csak, Abhishek Satishchandran, Karen Kodys, Evelyn A. Kurt-Jones, Katherine A. Fitzgerald, Gyongyi Szabo

Gyongyi Szabo

Emerging evidence suggests that innate immunity drives alcoholic liver disease (ALD) and that the interferon regulatory factor 3 (IRF3),a transcription factor regulating innate immune responses, is indispensable for the development of ALD. Here we report that IRF3 mediates ALD via linking endoplasmic reticulum (ER) stress with apoptotic signaling in hepatocytes. We found that ethanol induced ER stress and triggered the association of IRF3 with the ER adaptor, stimulator of interferon genes (STING), as well as subsequent phosphorylation of IRF3. Activated IRF3 associated with the proapoptotic molecule Bax [B-cell lymphoma 2 (Bcl2)-associated X protein] and contributed to hepatocyte apoptosis. Deficiency of …

Microrna Signature In Alcoholic Liver Disease, Shashi Bala, Gyongyi Szabo

Gyongyi Szabo

Alcoholic liver disease (ALD) is a major global health problem. Chronic alcohol use results in inflammation and fatty liver, and in some cases, it leads to fibrosis and cirrhosis or hepatocellular carcinoma. Increased proinflammatory cytokines, particularly TNF alpha, play a central role in the pathogenesis of ALD. TNF alpha is tightly regulated at transcriptional and posttranscriptional levels. Recently, microRNAs (miRNAs) have been shown to modulate gene functions. The role of miRNAs in ALD is getting attention, and recent studies suggest that alcohol modulates miRNAs. Recently, we showed that alcohol induces miR-155 expression both in vitro (RAW 264.7 macrophage) and in …

Human Monoclonal Antibody Hcv1 Effectively Prevents And Treats Hcv Infection In Chimpanzees, Trevor J. Morin, Teresa J. Broering, Brett A. Leav, Barbara M. Blair, Kirk J. Rowley, Elisabeth N. Boucher, Yang Wang, Peter S. Cheslock, Michael Knauber, David B. Olsen, Steve W. Ludmerer, Gyongyi Szabo, Robert W. Finberg, Robert H. Purcell, Robert E. Lanford, Donna M. Ambrosino, Deborah C. Molrine, Gregory J. Babcock

Gyongyi Szabo

Hepatitis C virus (HCV) infection is a leading cause of liver transplantation and there is an urgent need to develop therapies to reduce rates of HCV infection of transplanted livers. Approved therapeutics for HCV are poorly tolerated and are of limited efficacy in this patient population. Human monoclonal antibody HCV1 recognizes a highly-conserved linear epitope of the HCV E2 envelope glycoprotein (amino acids 412-423) and neutralizes a broad range of HCV genotypes. In a chimpanzee model, a single dose of 250 mg/kg HCV1 delivered 30 minutes prior to infusion with genotype 1a H77 HCV provided complete protection from HCV infection, …

Il-1 Receptor Antagonist Ameliorates Inflammasome-Dependent Alcoholic Steatohepatitis In Mice, Jan Petrasek, Shashi Bala, Timea Csak, Dora Lippai, Karen Kodys, Victoria Menashy, Matthew Barrieau, So-Yun Min, Evelyn A. Kurt-Jones, Gyongyi Szabo

Gyongyi Szabo

Alcoholic liver disease (ALD) is characterized by steatosis and upregulation of proinflammatory cytokines, including IL-1beta. IL-1beta, type I IL-1 receptor (IL-1R1), and IL-1 receptor antagonist (IL-1Ra) are all important regulators of the IL-1 signaling complex, which plays a role in inflammation. Furthermore, IL-1beta maturation is dependent on caspase-1 (Casp-1). Using IL-1Ra-treated mice as well as 3 mouse models deficient in regulators of IL-1beta activation (Casp-1 and ASC) or signaling (IL-1R1), we found that IL-1beta signaling is required for the development of alcohol-induced liver steatosis, inflammation, and injury. Increased IL-1beta was due to upregulation of Casp-1 activity and inflammasome activation. The …

Plasma Microrna Profiles Distinguish Lethal Injury In Acetaminophen Toxicity: A Research Study, Jeanine Ward, Shashi Bala, Jan Petrasek, Gyongyi Szabo

Gyongyi Szabo

AIM: To investigate plasma microRNA (miRNA) profiles indicative of hepatotoxicity in the setting of lethal acetaminophen (APAP) toxicity in mice. METHODS: Using plasma from APAP poisoned mice, either lethally (500 mg/kg) or sublethally (150 mg/kg) dosed, we screened commercially available murine microRNA libraries (SABiosciences, Qiagen Sciences, MD) to evaluate for unique miRNA profiles between these two dosing parameters. RESULTS: We distinguished numerous, unique plasma miRNAs both up- and downregulated in lethally compared to sublethally dosed mice. Of note, many of the greatest up- and downregulated miRNAs, namely 574-5 p, 466 g, 466 f-3p, 375, 29 c, and 148 a, have …

Lipopolysaccharide Induces And Activates The Nalp3 Inflammasome In The Liver, Michal Ganz, Timea Csak, Bharath D. Nath, Gyongyi Szabo

Gyongyi Szabo

AIM: To examine the activation of the Nalp3 inflammasome and its downstream targets following lipopolysaccharide (LPS)-induced stimulation in the liver. METHODS: Six-to-eight-week-old C57BL/6 chow fed mice were injected intraperitoneally with 0.5 mug/g bodyweight LPS and sacrificed 2, 4, 6, 18 or 24 h later. LPS-induced liver damage was confirmed by a biochemical assay to detect alanine aminotransferase (ALT) levels. To determine if LPS stimulation in the liver led to activation of the inflammasome, real-time quantitative polymerase chain reaction was used to evaluate the mRNA expression of components of the Nalp3 inflammasome. Enzyme-linked immunosorbent assays were used to determine the protein …

Increased Microrna-155 Expression In The Serum And Peripheral Monocytes In Chronic Hcv Infection, Shashi Bala, Yaphet Tilahun, Odette Taha, Hawau Alao, Karen Kodys, Donna Catalano, Gyongyi Szabo

Gyongyi Szabo

BACKGROUND: Hepatitis C Virus (HCV), a single stranded RNA virus, affects millions of people worldwide and leads to chronic infection characterized by chronic inflammation in the liver and in peripheral immune cells. Chronic liver inflammation leads to progressive liver damage. MicroRNAs (miRNA) regulate inflammation (miR-155, -146a and -125b) as well as hepatocyte function (miR-122). METHODS: Here we hypothesized that microRNAs are dysregulated in chronic HCV infection. We examined miRNAs in the circulation and in peripheral monocytes of patients with chronic HCV infection to evaluate if specific miRNA expression correlated with HCV infection. RESULTS: We found that monocytes from chronic HCV …

Serum Microrna-122 And Mir-155 As Biomarkers Of Liver Injury And Inflammation In Models Of Acute And Chronic Liver Disease, Shashi Bala, Jan Petrasek, Shiv Mundkur, Donna Catalano, Jeanine Ward, Ivan Levin, Hawau Alao, Karen Kodys, Gyongyi Szabo

Gyongyi Szabo

Background: MicroRNAs (miRs) are small non-coding molecules that regulate gene expression. MiRs expression levels change not only in diseased tissues but also in circulation. Further, miRs are stable in frozen samples that make them attractive for biomarker discovery. Recent reports suggest altered expression of circulating miRNAs in various diseases. MiR-122 is highly abundant in hepatocytes where it regulates different metabolic pathways while miR-155 is a central regulator of inflammation. The aim of this study was to evaluate circulating miRNAs as potential markers of hepatocyte damage and inflammation in liver diseases. Methods: Serum/plasma and liver samples were collected from C57/BL6 mice …

Increased Oxidative Capacity Of Circulating Polymorphonuclear Neutrophils (Pmns) In Non-Diabetic Nash Patients, Timea Csak, Karen Kodys, Angela Dolganiuc, Dora Lippai, Michal Ganz, Christopher Marshall, Gyongyi Szabo

Gyongyi Szabo

Background: Inflammation and oxidative stress are key factors in the pathogenesis of non-alcoholic steatohepatitis (NASH). Polymorphonuclear neutrophils are capable to produce significant amounts of reactive oxygen species (ROS) via the NADPH oxidase complex. Increased hepatic neutrophil infiltration has been described in steatohepatitis. We aimed to investigate the in vitro ROS generation by neutrophils of NASH patients and the hepatic NADPH oxidase activity in murine steatohepatitis. Material and methods: PMNs were isolated from peripheral blood of NASH patients (n=16) and healthy controls (n=16). In vitro ROS production was measured by luminol chemiluminescence after phorbol myristate acetate (PMA) or opsonized zymosan stimulation. …

Caspase-1-Dependent, Il-1ss-Mediated Alcoholic Steatohepatitis Is Ameliorated By Il-1 Receptor Antagonist Treatment In Mice, Jan Petrasek, Shashi Bala, Dora Lippai, Karen Kodys, Victoria Menashy, Matthew Barrieau, Evelyn A. Kurt-Jones, Gyongyi Szabo

Gyongyi Szabo

Alcoholic liver disease (ALD) is characterized by steatosis and upregulation of pro-inflammatory cytokines, including interleukin (IL)-1β. IL-1β, Type-I IL-1 receptor (IL1R1) and IL-1 receptor antagonist (IL-1Ra) are all part of the IL-1 superfamily that play a role in inflammation. IL-1β maturation is dependent on Caspase-1. Using wild-type (WT), Caspase-1-, IL-1R1- and IL-1Ra deficient mice fed with Lieber-DeCarli alcohol or control diet, we have identified that signaling mediated by the active IL-1β was required for development of alcohol-induced steatosis, inflammation and injury. Increased IL-1β was due to upregulation of Caspase-1 activity and inflammatory activation. The pathogenic role of IL-1 signaling in …

Cd81/Cd9 Tetraspanins Aid Plasmacytoid Dendritic Cells In Recognition Of Hcv-Infected Cells And Induction Of Ifnα, Shuye Zhang, Karen Kodys, Gyongyi Szabo

Gyongyi Szabo

Recognition of hepatitis C virus (HCV)-infected hepatocyes and interferon (IFN) induction are critical in antiviral immune response. We hypothesized that cell-cell contact between pDCs and HCV-infected cells was required for IFNα induction via involvement of cell surface molecules. Co-culture of human peripheral blood mononuclear cells (PBMCs) with genotype 1a full length HCV genomic replicon cells (FL) or genotype 2a JFH-1 virus infected hepatoma cells (JFH-1), not with uninfected hepatoma cells (Huh7.5), induced IFNα production. Depletion of pDCs from PBMCs attenuated IFNα release and purified pDCs produced high levels of IFNα after co-culture with FL replicons or JFH-1 infected cells. IFNα …

Toll-Like Receptors In The Pathogenesis Of Alcoholic Liver Disease, Jan Petrasek, Pranoti Mandrekar, Gyongyi Szabo

Gyongyi Szabo

In the multifactorial pathophysiology of alcoholic liver disease (ALD), inflammatory cascade activation plays a central role. Recent studies demonstrated that Toll-like Receptors, the sensors of microbial and endogenous danger signals, are expressed and activated in innate immune cells as well as in parenchymal cells in the liver and thereby contribute to ALD. In this paper, we discuss the importance of gut-derived endotoxin and its recognition by TLR4. The significance of TLR-induced intracellular signaling pathways and cytokine production as well as the contribution of reactive oxygen radicals is evaluated. The contribution of TLR signaling to induction of liver fibrosis and hepatocellular …

Inhibition Of Tlr8- And Tlr4-Induced Type I Ifn Induction By Alcohol Is Different From Its Effects On Inflammatory Cytokine Production In Monocytes, Maoyin Pang, Shashi Bala, Karen Kodys, Donna Catalano, Gyongyi Szabo

Gyongyi Szabo

BACKGROUND: Prolonged alcohol consumption is a significant co-factor in the progression of chronic viral infections including hepatitis C and HIV, which are both single-stranded RNA viruses. Toll like receptor 8 (TLR8), a pattern recognition receptor expressed in monocytes, senses viral single stranded RNA as a danger signal and leads to the induction of Type I interferon (IFN) as well as the pro-inflammatory cytokine, tumor necrosis factor alpha (TNF alpha). Lipopolysaccharide (LPS), a Toll like receptor 4 (TLR4) ligand, was shown to affect inflammatory cell activation after alcohol consumption and in HIV and HCV infections. Here we hypothesized that alcohol exposure …

Toll-Like Receptor Signaling In Liver Diseases, Gyongyi Szabo, Timothy R. Billiar, Keigo Machida, Ian Nicholas Crispe, Ekihiro Seki

Gyongyi Szabo

No abstract provided.

Emerging Role Of Micrornas In Liver Diseases, Shashi Bala, Miguel Marcos, Gyongyi Szabo

Gyongyi Szabo

MicroRNAs are a class of small non-coding RNAs that are found in plants, animals, and some viruses. They modulate the gene function at the post-transcriptional level and act as a fine tuner of various processes, such as development, proliferation, cell signaling, and apoptosis. They are associated with different types and stages of cancer. Recent studies have shown the involvement of microRNAs in liver diseases caused by various factors, such as Hepatitis C, Hepatitis B, metabolic disorders, and by drug abuse. This review highlights the role of microRNAs in liver diseases and their potential use as therapeutic molecules.

In Vitro And In Vivo Models Of Acute Alcohol Exposure, Angela Dolganiuc, Gyongyi Szabo

Gyongyi Szabo

Alcohol abuse is a global problem due to the financial burden on society and the healthcare system. While the harmful health effects of chronic alcohol abuse are well established, more recent data suggest that acute alcohol consumption also affects human wellbeing. Thus, there is a need for research models in order to fully understand the effect of acute alcohol abuse on different body systems and organs. The present manuscript summarizes the interdisciplinary advantages and disadvantages of currently available human and non-human models of acute alcohol abuse, and identifies their suitability for biomedical research.

Distinct Toll-Like Receptor Expression In Monocytes And T Cells In Chronic Hcv Infection, Angela Dolganiuc, Catherine Garcia, Karen Kodys, Gyongyi Szabo

Gyongyi Szabo

AIM: Hepatitis C virus often establishes chronic infections. Recent studies suggest that viral and bacterial infections are more common in HCV-infected patients compared to controls. Pathogens are recognized by Toll-like receptors (TLRs) to shape adaptive and innate immune responses.

METHODS: In this study, to assess the ability of HCV-infected host to recognize invading pathogens, we investigated Toll-like receptor expression in innate (monocytes) and adaptive (T cells) immune cells by real-time PCR.

RESULTS: We determined that RNA levels for TLRs 2, 6. 7, 8, 9 and 10 mRNA levels were upregulated in both monocytes and T cells in HCV-infected patients compared …