Intestinal Epithelial Cell-Derived Extracellular Vesicles Modulate Hepatic Injury via the Gut-Liver Axis During Acute Alcohol Injury.

Binge drinking, i.e., heavy episodic drinking in a short time, has recently become an alarming societal problem with negative health impact. However, the harmful effects of acute alcohol injury in the gut-liver axis remain elusive. Hence, we focused on the physiological and pathological changes and the underlying mechanisms of experimental binge drinking in the context of the gut-liver axis. Eight-week-old mice with a C57BL/6 background received a single dose (p.o.) of ethanol (EtOH) [6 g/kg b.w.] as a preclinical model of acute alcohol injury. Controls received a single dose of PBS. Mice were sacrificed 8 h later. In parallel, HepaRGs and Caco-2 cells, human cell lines of differentiated hepatocytes and intestinal epithelial cells intestinal epithelial cells (IECs), respectively, were challenged in the presence or absence of EtOH [0-100 mM]. Extracellular vesicles (EVs) isolated by ultracentrifugation from culture media of IECs were added to hepatocyte cell cultures. Increased intestinal permeability, loss of zonula occludens-1 (ZO-1) and MUCIN-2 expression, and alterations in microbiota-increased Lactobacillus and decreased Lachnospiraceae species-were found in the large intestine of mice exposed to EtOH. Increased TUNEL-positive cells, infiltration of CD11b-positive immune cells, pro-inflammatory cytokines (e.g., tlr4, tnf, il1β), and markers of lipid accumulation (Oil Red O, srbep1) were evident in livers of mice exposed to EtOH, particularly in females. In vitro experiments indicated that EVs released by IECs in response to ethanol exerted a deleterious effect on hepatocyte viability and lipid accumulation. Overall, our data identified a novel mechanism responsible for driving hepatic injury in the gut-liver axis, opening novel avenues for therapy.This work was supported by the MINECO Retos SAF2016-78711, SAF2017-87919-R, EXOHEP-CM S2017/BMD-3727, NanoLiver-CM Y2018/NMT-4949, ERAB Ref. EA 18/14, AMMF 2018/117, UCM-25-2019 and COST Action CA17112, the German Research Foundation (SFB/TRR57/P04, SFB 1382-403224013/A02, and DFG NE 2128/2-1). FC and YN are Ramón y Cajal Researchers RYC-2014-15242 and RYC-2015-17438. FC is a Gilead Liver Research 2018. KZ is a recipient of a Chinese Scholarship Council (CSC). BK20170127 from the Natural Science Foundation of Jiangsu Province to JP.S

An Experimental DUAL Model of Advanced Liver Damage

Individuals exhibiting an intermediate alcohol drinking pattern in conjunction with signs of metabolic risk present clinical features of both alcohol-associated and metabolic-associated fatty liver diseases. However, such combination remains an unexplored area of great interest, given the increasing number of patients affected. In the present study, we aimed to develop a preclinical DUAL (alcohol-associated liver disease plus metabolic-associated fatty liver disease) model in mice. C57BL/6 mice received 10% vol/vol alcohol in sweetened drinking water in combination with a Western diet for 10, 23, and 52 weeks (DUAL model). Animals fed with DUAL diet elicited a significant increase in body mass index accompanied by a pronounced hypertrophy of adipocytes, hypercholesterolemia, and hyperglycemia. Significant liver damage was characterized by elevated plasma alanine aminotransferase and lactate dehydrogenase levels, extensive hepatomegaly, hepatocyte enlargement, ballooning, steatosis, hepatic cell death, and compensatory proliferation. Notably, DUAL animals developed lobular inflammation and advanced hepatic fibrosis. Sequentially, bridging cirrhotic changes were frequently observed after 12 months. Bulk RNA-sequencing analysis indicated that dysregulated molecular pathways in DUAL mice were similar to those of patients with steatohepatitis. Conclusion: Our DUAL model is characterized by obesity, glucose intolerance, liver damage, prominent steatohepatitis and fibrosis, as well as inflammation and fibrosis in white adipose tissue. Altogether, the DUAL model mimics all histological, metabolic, and transcriptomic gene signatures of human advanced steatohepatitis, and therefore serves as a preclinical tool for the development of therapeutic targets.Supported by EXOHEP-CM (S2017/BMD-3727), Ramón y Cajal (RYC-2014-15242 and RYC-2015-17438), NanoLiver-CM (Y2018/NMT-4949), COST Action (CA17112), AMMF (2018/117), ERAB (EA 18/14), MINECO Retos (SAF2016-78711 and SAF2017-87919-R), and German Research Foundation (DFG NE 2128/2-1, SFB 1382-403224013/A02, and SFB/TRR57/P04). FJC is a Gilead Research Liver Scholar. The research group belongs to the validated Research group Ref. 970935 “Liver Pathophysiology”, 920631 “Lymphocyte immunology”, 920361 “Immunogenética e inmunología de las mucosas” and IBL-6 (imas12-associated). FG and KZ are Chinese Scholarship Council (CSC) fellows. O.E.-V is supported by Beca FPI (associated to MINECO SAF2017-87919R) and R.B.-U. by Contratos predoctorales de personal investigador en formación UCM-Banco Santander (CT63/19)

A Shortcut from Metabolic-Associated Fatty Liver Disease (MAFLD) to Hepatocellular Carcinoma (HCC): c-MYC a Promising Target for Preventative Strategies and Individualized Therapy

Background: Metabolic-associated fatty liver disease (MAFLD) has risen as one of the leading etiologies for hepatocellular carcinoma (HCC). Oncogenes have been suggested to be responsible for the high risk of MAFLD-related HCC. We analyzed the impact of the proto-oncogene c-MYC in the development of human and murine MAFLD and MAFLD-associated HCC. Methods: alb-myctg mice were studied at baseline conditions and after administration of Western diet (WD) in comparison to WT littermates. c-MYC expression was analyzed in biopsies of patients with MAFLD and MAFLD-associated HCC by immunohistochemistry. Results: Mild obesity, spontaneous hyperlipidaemia, glucose intolerance and insulin resistance were characteristic of 36-week-old alb-myctg mice. Middle-aged alb-myctg exhibited liver steatosis and increased triglyceride content. Liver injury and inflammation were associated with elevated ALT, an upregulation of ER-stress response and increased ROS production, collagen deposition and compensatory proliferation. At 52 weeks, 20% of transgenic mice developed HCC. WD feeding exacerbated metabolic abnormalities, steatohepatitis, fibrogenesis and tumor prevalence. Therapeutic use of metformin partly attenuated the spontaneous MAFLD phenotype of alb-myctg mice. Importantly, upregulation and nuclear localization of c-MYC were characteristic of patients with MAFLD and MAFLD-related HCC. Conclusions: A novel function of c-MYC in MAFLD progression was identified opening new avenues for preventative strategies

A Shortcut from Metabolic-Associated Fatty Liver Disease (MAFLD) to Hepatocellular Carcinoma (HCC): c-MYC a Promising Target for Preventative Strategies and Individualized Therapy

Background: Metabolic-associated fatty liver disease (MAFLD) has risen as one of the leading etiologies for hepatocellular carcinoma (HCC). Oncogenes have been suggested to be responsible for the high risk of MAFLD-related HCC. We analyzed the impact of the proto-oncogene c-MYC in the development of human and murine MAFLD and MAFLD-associated HCC. Methods: alb-myctg mice were studied at baseline conditions and after administration of Western diet (WD) in comparison to WT littermates. c-MYC expression was analyzed in biopsies of patients with MAFLD and MAFLD-associated HCC by immunohistochemistry. Results: Mild obesity, spontaneous hyperlipidaemia, glucose intolerance and insulin resistance were characteristic of 36-week-old alb-myctg mice. Middle-aged alb-myctg exhibited liver steatosis and increased triglyceride content. Liver injury and inflammation were associated with elevated ALT, an upregulation of ER-stress response and increased ROS production, collagen deposition and compensatory proliferation. At 52 weeks, 20% of transgenic mice developed HCC. WD feeding exacerbated metabolic abnormalities, steatohepatitis, fibrogenesis and tumor prevalence. Therapeutic use of metformin partly attenuated the spontaneous MAFLD phenotype of alb-myctg mice. Importantly, upregulation and nuclear localization of c-MYC were characteristic of patients with MAFLD and MAFLD-related HCC. Conclusions: A novel function of c-MYC in MAFLD progression was identified opening new avenues for preventative strategies

Role of p21/CDKN1A in chronic liver disease (CLD)

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Medicina, leída el 06-07-2022La creciente incidencia de la obesidad y la enfermedad del hígado graso no alcohólico (EHGNA/NASH) representa una seria amenaza para la salud mundial, pudiendo conducir a un aumento en el número de casos de enfermedad hepática avanzada, cirrosis y en última instancia derivar en carcinoma hepatocelular (CHC). El gen p21/CDKN1A es un regulador del ciclo celular que está involucrado en procesos celulares esenciales tales como: la detención del ciclo celular, la apoptosis, la diferenciación, la senescencia y la reparación del ADN. El objetivo principal de este estudio fue determinar el papel específico de p21/CDKN1A en la enfermedad hepática crónica...The increasing incidence of obesity and non-alcoholic fatty liver disease(NAFLD/NASH) currently represents a serious threat to global health, potentially leadingto an increase in the number of cases of advanced liver disease, cirrhosis and, ultimately,leading to hepatocellular carcinoma (HCC). The p21/CDKN1A gene is a cell cycleregulator that is involved in essential cellular processes such as: cell cycle arrest,apoptosis, differentiation, senescence, and DNA repair. The main aim of this study wasto evaluate the specific role of p21/CDKN1A in chronic liver disease (CLD)...Fac. de MedicinaTRUEunpu

Alcoholic liver disease: Utility of animal models

Alcoholic liver disease (ALD) is a major cause of acute and chronic liver injury. Extensive evidence has been accumulated on the pathological process of ALD during the past decades. However, effective treatment options for ALD are very limited due to the lack of suitable in vivo models that recapitulate the full spectrum of ALD. Experimental animal models of ALD, particularly rodents, have been used extensively to mimic human ALD. An ideal animal model should recapitulate all aspects of the ALD process, including significant steatosis, hepatic neutrophil infiltration, and liver injury. A better strategy against ALD depends on clear diagnostic biomarkers, accurate predictor(s) of its progression and new therapeutic approaches to modulate stop or even reverse the disease. Numerous models employing rodent animals have been established in the last decades to investigate the effects of acute and chronic alcohol exposure on the initiation and progression of ALD. Although significant progress has been made in gaining better knowledge on the mechanisms and pathology of ALD, many features of ALD are unknown, and require further investigation, ideally with improved animal models that more effectively mimic human ALD. Although differences in the degree and stages of alcoholic liver injury inevitably exist between animal models and human ALD, the acquisition and translational relevance will be greatly enhanced with the development of new and improved animal models of ALD.Supported by the MINECO Retos, No. SAF2016-78711 and SAF2017-87919R; EXOHEP-CM, No. S2017/BMD-3727; the AMMF Cholangiocarcinoma Charity, No. 2018/117; the COST Action, No. CA17112; Ramón y Cajal, No. RYC-2014-15242 and No. RYC-2015-17438; grant of ERAB, No. EA 14/18; Gilead Liver Research Scholar 2018, No. 44/2018; Ministerio de Sanidad, Servicios Sociales e Igualdad, No. 2017I065; and the UCM group “Lymphocyte Immunobiology”, No. 920631 (imas12-associated, Ref. IBL-6). German Research Foundation (SFB/TRR57/P04 and DFG NE 2128/2-1); Interdisciplinary Center for Clinical Research from the Faculty of Medicine at RWTH Aachen University (IZKF/E8-2).Peer reviewe

Intestinal Epithelial Cell-Derived Extracellular Vesicles Modulate Hepatic Injury via the Gut-Liver Axis During Acute Alcohol Injury

Binge drinking, i.e., heavy episodic drinking in a short time, has recently become an alarming societal problem with negative health impact. However, the harmful effects of acute alcohol injury in the gut-liver axis remain elusive. Hence, we focused on the physiological and pathological changes and the underlying mechanisms of experimental binge drinking in the context of the gut-liver axis. Eight-week-old mice with a C57BL/6 background received a single dose (p.o.) of ethanol (EtOH) [6 g/kg b.w.] as a preclinical model of acute alcohol injury. Controls received a single dose of PBS. Mice were sacrificed 8 h later. In parallel, HepaRGs and Caco-2 cells, human cell lines of differentiated hepatocytes and intestinal epithelial cells intestinal epithelial cells (IECs), respectively, were challenged in the presence or absence of EtOH [0-100 mM]. Extracellular vesicles (EVs) isolated by ultracentrifugation from culture media of IECs were added to hepatocyte cell cultures. Increased intestinal permeability, loss of zonula occludens-1 (ZO-1) and MUCIN-2 expression, and alterations in microbiota-increased Lactobacillus and decreased Lachnospiraceae species-were found in the large intestine of mice exposed to EtOH. Increased TUNEL-positive cells, infiltration of CD11b-positive immune cells, pro-inflammatory cytokines (e.g., tlr4, tnf, il1β), and markers of lipid accumulation (Oil Red O, srbep1) were evident in livers of mice exposed to EtOH, particularly in females. In vitro experiments indicated that EVs released by IECs in response to ethanol exerted a deleterious effect on hepatocyte viability and lipid accumulation. Overall, our data identified a novel mechanism responsible for driving hepatic injury in the gut-liver axis, opening novel avenues for therapyMinisterio de Economía, Comercio y EmpresaUniversidad Complutense de MadridGerman Research FoundationDepto. de MedicinaDepto. de Farmacología y ToxicologíaFac. de MedicinaTRUEpu

Lack of Cyclin E1 in hepatocytes aggravates ethanol-induced liver injury and hepatic steatosis in experimental murine model of acute and chronic alcohol-associated liver disease

Background: Cyclin E1 is the regulatory subunit of cyclin-dependent kinase 2 (Cdk2) and one of the central players in cell cycle progression. We recently showed its crucial role for initiation of liver fibrosis and hepatocarcinogenesis. In the present study, we investigated the role of Cyclin E1 in the development of alcohol-associated liver disease (ALD). Methods: Mice with constitutive (E1-/-), hepatocyte-specific (Cyclin E1Δhepa), or intestinal-epithelial-cell-specific (Cyclin E1ΔIEC) inactivation of Cyclin E1 and corresponding wild type littermate controls (WT) were administered either a Lieber-DeCarli ethanol diet (LDE) for 3 weeks or acute ethanol binges (6 g/kg) through oral gavage. Serum parameters of liver functionality were measured; hepatic tissues were collected for biochemical and histological analyses. Results: The administration of acute EtOH binge and chronic LDE diet to E1-/- mice enhanced hepatic steatosis, worsened liver damage and triggered body weight loss. Similarly, in the acute EtOH binge model, Cyclin E1Δhepa mice revealed a significantly worsened liver phenotype. In contrast, inactivation of Cyclin E1 only in intestinal epithelial cell (IECs)did not lead to any significant changes in comparison to WT mice after acute EtOH challenge. Remarkably, both acute and chronic EtOH administration in E1-/- animals resulted in increased levels of ADH and decreased expression of ALDH1/2. The additional application of a pan-Cdk inhibitor (S-CR8) further promoted liver damage in EtOH-treated WT mice. Conclusion: Our data point to a novel unexpected role of Cyclin E1 in hepatocytes for alcohol metabolism, which seems to be independent of the canonical Cyclin E1/Cdk2 function as a cell cycle regulator.Fundación Alemana de Investigación (DFG)Ministerio de Asuntos Económicos y Transformación Digital (MINECO)Ministerio de Ciencia e Innovación (MICIN)Unión EuropeaComunidad de Madrid. Fundación para la Investigación Biomédica del Hospital Universitario de Getafe (FIBHGM)European Cooperation in Science & Technology (COST)Universidad Complutense de Madrid /Banco SantanderDepto. de Genética, Fisiología y MicrobiologíaDepto. de Inmunología, Oftalmología y ORLFac. de Ciencias BiológicasFac. de MedicinaTRUEpu