Integrin inhibitor cycloRGDfV blunts enhanced LPS-induced liver injury caused by ethanol in mice.

Background. Progression of alcoholic liver disease (ALD) is associated with an increase in fibrin extracellular matrix (ECM) and inflammation. Previous studies have shown that this accumulation of fibrin in ALD is mediated by impaired fibrinolysis. Additionally, it is known that fibrin(ogen) interacts with the av~3 integrin of endothelial cells. The purpose of this study was to test the hypothesis that hepatic inflammation caused by alcohol is mediated, at least in part, by activation of integrin av~3 by fibrin(ogen). To test this hypothesis, a study was designed to determine the effect of cycloRGDN, a peptide inhibitor of integrin av~3, in a mouse model of lipopolysaccharide (LPS)-induced inflammation enhanced by ethanol pre-exposure. Methods. Accordingly, male C57BLl6J mice were exposed to ethanol (6 g/kg i.g.) or isocaloric/isovolumetric maltose dextrin solution for 3 days and injected with lipopolysaccharide (LPS; 10 mg/kg i.p.) 24 hours after the last dose of ethanol. Some animals received the avß3 integrin inhibitor (cycloRGDN; 3 mg/kg i.p.) 1 hour prior to LPS administration. Animals were sacrificed 8 or 24 hours after LPS administration. Liver damage was assessed by plasma (AL T, AST) and histological indices of liver damage (hematoxylin and eosin; H&E) and inflammation (chloroacetate esterase; CAE). Results. Ethanol pre-exposure enhanced liver injury due to LPS, as indicated by a significant increase in plasma AL T levels. cycloRGDN significantly attenuated the increase in plasma AL T caused by ethanol pre-exposure. These results were supported by histological changes. Animals that received ethanol and LPS had both larger and more numerous necroinflammatory foci compared to animals that received LPS alone. The number and severity of necroinflammatory foci was reduced by cycloRGDN compared to LPS + ethanol. Ethanol pre-exposure enhanced the increase in neutrophil migration caused by LPS, as determined by CAE staining. Animals administered cycloRGDN had fewer infiltrating neutrophils compared to those that received a combination of ethanol and LPS. Conclusions. These data suggest that cycloRGDN administration protects against liver injury caused by a combination of alcohol and LPS exposure. CycloRGDN also blunts ethanol-enhanced neutrophil infiltration caused by LPS in this model. Therefore, integrin avß3 may play an important role in enhanced hepatic inflammation and injury due to LPS after ethanol pre-exposure

Acute Alcohol-Induced Liver Injury

Alcohol consumption is customary in most cultures and alcohol abuse is common worldwide. For example, more than 50% of Americans consume alcohol, with an estimated 23.1% of Americans participating in heavy and/or binge drinking at least once a month. A safe and effective therapy for alcoholic liver disease (ALD) in humans is still elusive, despite significant advances in our understanding of how the disease is initiated and progresses. It is now clear that acute alcohol binges not only can be acutely toxic to the liver, but also can contribute to the chronicity of ALD. Potential mechanisms by which acute alcohol causes damage include steatosis, dysregulated immunity and inflammation, and altered gut permeability. Recent interest in modeling acute alcohol exposure has yielded new insights into potential mechanisms of acute injury, which also may well be relevant for chronic ALD. Recent work by this group on the role of PAI-1 and fibrin metabolism in mediating acute alcohol-induced liver damage serve as an example of possible new targets that may be useful for alcohol abuse, be it acute or chronic

Defective HNF4alpha-dependent gene expression as a driver of hepatocellular failure in alcoholic hepatitis

RNA sequencing in livers; TGFβ1; Epigenetic driversSeqüenciació d’ARN en el fetge; TGFβ1; Controladors epigenèticsSecuenciación de ARN en el hígado; TGFβ1; Controladores epigenéticosAlcoholic hepatitis (AH) is a life-threatening condition characterized by profound hepatocellular dysfunction for which targeted treatments are urgently needed. Identification of molecular drivers is hampered by the lack of suitable animal models. By performing RNA sequencing in livers from patients with different phenotypes of alcohol-related liver disease (ALD), we show that development of AH is characterized by defective activity of liver-enriched transcription factors (LETFs). TGFβ1 is a key upstream transcriptome regulator in AH and induces the use of HNF4α P2 promoter in hepatocytes, which results in defective metabolic and synthetic functions. Gene polymorphisms in LETFs including HNF4α are not associated with the development of AH. In contrast, epigenetic studies show that AH livers have profound changes in DNA methylation state and chromatin remodeling, affecting HNF4α-dependent gene expression. We conclude that targeting TGFβ1 and epigenetic drivers that modulate HNF4α-dependent gene expression could be beneficial to improve hepatocellular function in patients with AH.This work was mainly supported by NIH/NIAAA funded Consortia "Integrated approaches for identifying molecular targets in alcoholic hepatitis" InTEAM (U01AA021908) (R.B., P.M., P.S-B., I.R., J.Cbl). This work was supported in part by: NIH/NIAAA (R01AA023781), USA (C.W.); Hepacare Project, Fundacion La Caixa, Spain (M.A.A., C.B. and M.U.L); Fond national de la recherche scientifique (FNRS J.0146.17) and Fond de la recherche scientifique medicale (FRSM T.0217.18), Belgium (P.S.); NIH/NCATS (UH3TR000503) and EPA (STAR 83573601), USA (D.L.V. and L.A.T.); MRC, UK (MK/K001949/1) and NIH/NIAAA, USA (UO1AA018663) (J.M.); NIH/NIAAA (1U01AA021908-01-33490), Instituto de Salud Carlos III (PI17/00673) and Miguel Servet (CPII16/00041) and "Una manera de hacer Europa" program, European Regional Development Fund (ERDF), EU (P.S-B.); National Institute for Health Research Imperial Biomedical Research Centre and NIHR Health Technology Assessment Grant 08-14-44 (M.R.T.); NIH T32, DK007052, USA (L.R.E.); NIH/NIAAA (1U01AA021908) and AFEF (P.M., L.D., A. L.)

Hepatic lipocalin 2 promotes liver fibrosis and portal hypertension

Advanced fibrosis and portal hypertension influence short-term mortality. Lipocalin 2 (LCN2) regulates infection response and increases in liver injury. We explored the role of intrahepatic LCN2 in human alcoholic hepatitis (AH) with advanced fibrosis and portal hypertension and in experimental mouse fibrosis. We found hepatic LCN2 expression and serum LCN2 level markedly increased and correlated with disease severity and portal hypertension in patients with AH. In control human livers, LCN2 expressed exclusively in mononuclear cells, while its expression was markedly induced in AH livers, not only in mononuclear cells but also notably in hepatocytes. Lcn2−/− mice were protected from liver fibrosis caused by either ethanol or CCl4 exposure. Microarray analysis revealed downregulation of matrisome, cell cycle and immune related gene sets in Lcn2−/− mice exposed to CCl4, along with decrease in Timp1 and Edn1 expression. Hepatic expression of COL1A1, TIMP1 and key EDN1 system components were elevated in AH patients and correlated with hepatic LCN2 expression. In vitro, recombinant LCN2 induced COL1A1 expression. Overexpression of LCN2 increased HIF1A that in turn mediated EDN1 upregulation. LCN2 contributes to liver fibrosis and portal hypertension in AH and could represent a new therapeutic target

Hepatic lipocalin 2 promotes liver fibrosis and portal hypertension

Advanced fibrosis and portal hypertension influence short-term mortality. Lipocalin 2 (LCN2) regulates infection response and increases in liver injury. We explored the role of intrahepatic LCN2 in human alcoholic hepatitis (AH) with advanced fibrosis and portal hypertension and in experimental mouse fibrosis. We found hepatic LCN2 expression and serum LCN2 level markedly increased and correlated with disease severity and portal hypertension in patients with AH. In control human livers, LCN2 expressed exclusively in mononuclear cells, while its expression was markedly induced in AH livers, not only in mononuclear cells but also notably in hepatocytes. Lcn2-/- mice were protected from liver fibrosis caused by either ethanol or CCl4 exposure. Microarray analysis revealed downregulation of matrisome, cell cycle and immune related gene sets in Lcn2-/- mice exposed to CCl4, along with decrease in Timp1 and Edn1 expression. Hepatic expression of COL1A1, TIMP1 and key EDN1 system components were elevated in AH patients and correlated with hepatic LCN2 expression. In vitro, recombinant LCN2 induced COL1A1 expression. Overexpression of LCN2 increased HIF1A that in turn mediated EDN1 upregulation. LCN2 contributes to liver fibrosis and portal hypertension in AH and could represent a new therapeutic target

Exogenous Liposomal ceramide-c6 ammeliorates lipidomic profile, energy homeostasis and anti-oxidant systems in NASH

In non-alcoholic steatohepatitis (NASH), many lines of investigation have reported a dysregulation in lipid homeostasis, leading to intrahepatic lipid accumulation. Recently, the role of dysfunctional sphingolipid metabolism has also been proposed. Human and animal models of NASH have been associated with elevated levels of long chain ceramides and pro-apoptotic sphingolipid metabolites, implicated in regulating fatty acid oxidation and inflammation. Importantly, inhibition of de novo ceramide biosynthesis or knock-down of ceramide synthases reverse some of the pathology of NASH. In contrast, cell permeable, short chain ceramides have shown anti-inflammatory actions in multiple models of inflammatory disease. Here, we investigated non-apoptotic doses of a liposome containing short chain C6-Ceramide (Lip-C6) administered to human hepatic stellate cells (hHSC), a key effector of hepatic fibrogenesis, and an animal model characterized by inflammation and elevated liver fat content. On the basis of the results from unbiased liver transcriptomic studies from non-alcoholic fatty liver disease patients, we chose to focus on adenosine monophosphate activated kinase (AMPK) and nuclear factor-erythroid 2-related factor (Nrf2) signaling pathways, which showed an abnormal profile. Lip-C6 administration inhibited hHSC proliferation while improving anti-oxidant protection and energy homeostasis, as indicated by upregulation of Nrf2, activation of AMPK and an increase in ATP. To confirm these in vitro data, we investigated the effect of a single tail-vein injection of Lip-C6 in the methionine-choline deficient (MCD) diet mouse model. Lip-C6, but not control liposomes, upregulated phospho-AMPK, without inducing liver toxicity, apoptosis, or exacerbating inflammatory signaling pathways. Alluding to mechanism, mass spectrometry lipidomics showed that Lip-C6-treatment reversed the imbalance in hepatic phosphatidylcholines and diacylglycerides species induced by the MCD-fed diet. These results reveal that short-term Lip-C6 administration reverses energy/metabolic depletion and increases protective anti-oxidant signaling pathways, possibly by restoring homeostatic lipid function in a model of liver inflammation with fat accumulation

Defective HNF4alpha-dependent gene expression as a driver of hepatocellular failure in alcoholic hepatitis

Alcoholic hepatitis (AH) is a life-threatening condition characterized by profound hepatocellular dysfunction for which targeted treatments are urgently needed. Identification of molecular drivers is hampered by the lack of suitable animal models. By performing RNA sequencing in livers from patients with different phenotypes of alcohol-related liver disease (ALD), we show that development of AH is characterized by defective activity of liver-enriched transcription factors (LETFs). TGFβ1 is a key upstream transcriptome regulator in AH and induces the use of HNF4α P2 promoter in hepatocytes, which results in defective metabolic and synthetic functions. Gene polymorphisms in LETFs including HNF4α are not associated with the development of AH. In contrast, epigenetic studies show that AH livers have profound changes in DNA methylation state and chromatin remodeling, affecting HNF4α-dependent gene expression. We conclude that targeting TGFβ1 and epigenetic drivers that modulate HNF4α-dependent gene expression could be beneficial to improve hepatocellular function in patients with AH

Obstetric Outcomes in Women with Rheumatic Disease and COVID-19 in the Context of Vaccination Status

OBJECTIVE: To describe obstetric outcomes based on COVID-19 vaccination status, in women with rheumatic and musculoskeletal diseases (RMDs) who developed COVID-19 during pregnancy. METHODS: Data regarding pregnant women entered into the COVID-19 Global Rheumatology Alliance registry from 24 March 2020-25 February 2022 were analysed. Obstetric outcomes were stratified by number of COVID-19 vaccine doses received prior to COVID-19 infection in pregnancy. Descriptive differences between groups were tested using the chi -square or Fisher's exact test. RESULTS: There were 73 pregnancies in 73 women with RMD and COVID-19. Overall, 24.7% (18) of pregnancies were ongoing, while of the 55 completed pregnancies 90.9% (50) of pregnancies resulted in livebirths. At the time of COVID-19 diagnosis, 60.3% (n = 44) of women were unvaccinated, 4.1% (n = 3) had received one vaccine dose while 35.6% (n = 26) had two or more doses. Although 83.6% (n = 61) of women required no treatment for COVID-19, 20.5% (n = 15) required hospital admission. COVID-19 resulted in delivery in 6.8% (n = 3) of unvaccinated women and 3.8% (n = 1) of fully vaccinated women. There was a greater number of preterm births (PTB) in unvaccinated women compared with fully vaccinated 29.5% (n = 13) vs 18.2%(n = 2). CONCLUSION: In this descriptive study, unvaccinated pregnant women with RMD and COVID-19 had a greater number of PTB compared with those fully vaccinated against COVID-19. Additionally, the need for COVID-19 pharmacological treatment was uncommon in pregnant women with RMD regardless of vaccination status. These results support active promotion of COVID-19 vaccination in women with RMD who are pregnant or planning a pregnancy

Why organizational and community diversity matter:Representativeness and the Emergence of Incivility and Organizational Performance

Integrating sociological and psychological perspectives, this research considers the value of organizational ethnic diversity as a function of community diversity. Employee and patient surveys, census data, and performance indexes relevant to 142 hospitals in the United Kingdom suggest that intraorganizational ethnic diversity is associated with reduced civility toward patients. However, the degree to which organizational demography was representative of community demography was positively related to civility experienced by patients and ultimately enhanced organizational performance. These findings underscore the understudied effects of community context and imply that intergroup biases manifested in incivility toward out-group members hinder organizational performance