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1.
Alcohol Clin Exp Res ; 46(12): 2245-2257, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36317527

RESUMO

BACKGROUND: High alcohol intake is associated with increased mortality. We aimed to identify factors affecting mortality in people drinking extreme amounts of alcohol. METHODS: We obtained information from the UK Biobank on approximately 500,000 participants aged 40-70 years at baseline assessment in 2006-2010. Habitual alcohol intake, lifestyle and physiological data, laboratory test results, and hospital diagnoses and death certificate data (to June 2020) for 5136 men (2.20% of male participants) and 1504 women (0.60%) who reported consuming ≥80 or ≥50 g/day, respectively, were used in survival analysis. RESULTS: Mortality hazard ratios for these excessive drinkers, compared to all other participants, were 2.02 (95% CI 1.89-2.17) for all causes, 1.89 (1.69-2.12) for any cancer, 1.87 (1.61-2.17) for any circulatory disease, and 9.40 (7.00-12.64) for any liver disease. Liver disease diagnosis or abnormal liver function tests predicted not only deaths attributed to liver disease but also those from cancers or circulatory diseases. Mortality among excessive drinkers was also associated with quantitative alcohol intake; diagnosed alcohol dependence, harmful use, or withdrawal syndrome; and current smoking at assessment. CONCLUSIONS: People with chronic excessive alcohol intake experience decreased average survival, but there is substantial variation in their mortality, with liver abnormality and alcohol dependence or other alcohol use disorders associated with a worse prognosis. Clinically, patients with these risk factors and high alcohol intake should be considered for early or intensive management. Research can usefully focus on the factors predisposing to dependence or liver abnormality.


Assuntos
Alcoolismo , Doenças Cardiovasculares , Humanos , Masculino , Feminino , Alcoolismo/epidemiologia , Alcoolismo/complicações , Consumo de Bebidas Alcoólicas/efeitos adversos , Bancos de Espécimes Biológicos , Fatores de Risco , Doenças Cardiovasculares/etiologia , Fígado , Reino Unido/epidemiologia
2.
J Hepatol ; 76(2): 275-282, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34656649

RESUMO

BACKGROUND & AIMS: Only a minority of excess alcohol drinkers develop cirrhosis. We developed and evaluated risk stratification scores to identify those at highest risk. METHODS: Three cohorts (GenomALC-1: n = 1,690, GenomALC-2: n = 3,037, UK Biobank: relevant n = 6,898) with a history of heavy alcohol consumption (≥80 g/day (men), ≥50 g/day (women), for ≥10 years) were included. Cases were participants with alcohol-related cirrhosis. Controls had a history of similar alcohol consumption but no evidence of liver disease. Risk scores were computed from up to 8 genetic loci identified previously as associated with alcohol-related cirrhosis and 3 clinical risk factors. Score performance for the stratification of alcohol-related cirrhosis risk was assessed and compared across the alcohol-related liver disease spectrum, including hepatocellular carcinoma (HCC). RESULTS: A combination of 3 single nucleotide polymorphisms (SNPs) (PNPLA3:rs738409, SUGP1-TM6SF2:rs10401969, HSD17B13:rs6834314) and diabetes status best discriminated cirrhosis risk. The odds ratios (ORs) and (95% CIs) between the lowest (Q1) and highest (Q5) score quintiles of the 3-SNP score, based on independent allelic effect size estimates, were 5.99 (4.18-8.60) (GenomALC-1), 2.81 (2.03-3.89) (GenomALC-2), and 3.10 (2.32-4.14) (UK Biobank). Patients with diabetes and high risk scores had ORs of 14.7 (7.69-28.1) (GenomALC-1) and 17.1 (11.3-25.7) (UK Biobank) compared to those without diabetes and with low risk scores. Patients with cirrhosis and HCC had significantly higher mean risk scores than patients with cirrhosis alone (0.76 ± 0.06 vs. 0.61 ± 0.02, p = 0.007). Score performance was not significantly enhanced by information on additional genetic risk variants, body mass index or coffee consumption. CONCLUSIONS: A risk score based on 3 genetic risk variants and diabetes status enables the stratification of heavy drinkers based on their risk of cirrhosis, allowing for the provision of earlier preventative interventions. LAY SUMMARY: Excessive chronic drinking leads to cirrhosis in some people, but so far there is no way to identify those at high risk of developing this debilitating disease. We developed a genetic risk score that can identify patients at high risk. The risk of cirrhosis is increased >10-fold with just two risk factors - diabetes and a high genetic risk score. Risk assessment using this test could enable the early and personalised management of this disease in high-risk patients.


Assuntos
Predisposição Genética para Doença/classificação , Cirrose Hepática Alcoólica/diagnóstico , Medição de Risco/métodos , Adulto , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/psicologia , Estudos de Casos e Controles , Estudos de Coortes , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/fisiopatologia , Feminino , Estudo de Associação Genômica Ampla/métodos , Estudo de Associação Genômica Ampla/estatística & dados numéricos , Humanos , Cirrose Hepática Alcoólica/etiologia , Cirrose Hepática Alcoólica/fisiopatologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Medição de Risco/estatística & dados numéricos
3.
Am J Gastroenterol ; 116(1): 106-115, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32868629

RESUMO

INTRODUCTION: Sustained high alcohol intake is necessary but not sufficient to produce alcohol-related cirrhosis. Identification of risk factors, apart from lifetime alcohol exposure, would assist in discovery of mechanisms and prediction of risk. METHODS: We conducted a multicenter case-control study (GenomALC) comparing 1,293 cases (with alcohol-related cirrhosis, 75.6% male) and 754 controls (with equivalent alcohol exposure but no evidence of liver disease, 73.6% male). Information confirming or excluding cirrhosis, and on alcohol intake and other potential risk factors, was obtained from clinical records and by interview. Case-control differences in risk factors discovered in the GenomALC participants were validated using similar data from 407 cases and 6,573 controls from UK Biobank. RESULTS: The GenomALC case and control groups reported similar lifetime alcohol intake (1,374 vs 1,412 kg). Cases had a higher prevalence of diabetes (20.5% (262/1,288) vs 6.5% (48/734), P = 2.27 × 10-18) and higher premorbid body mass index (26.37 ± 0.16 kg/m2) than controls (24.44 ± 0.18 kg/m2, P = 5.77 × 10-15). Controls were significantly more likely to have been wine drinkers, coffee drinkers, smokers, and cannabis users than cases. Cases reported a higher proportion of parents who died of liver disease than controls (odds ratio 2.25 95% confidence interval 1.55-3.26). Data from UK Biobank confirmed these findings for diabetes, body mass index, proportion of alcohol as wine, and coffee consumption. DISCUSSION: If these relationships are causal, measures such as weight loss, intensive treatment of diabetes or prediabetic states, and coffee consumption should reduce the risk of alcohol-related cirrhosis.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Café , Diabetes Mellitus/epidemiologia , Cirrose Hepática Alcoólica/epidemiologia , Uso da Maconha/epidemiologia , Obesidade/epidemiologia , Fumar/epidemiologia , Chá , Bebidas Alcoólicas , Austrália/epidemiologia , Estudos de Casos e Controles , Feminino , França/epidemiologia , Alemanha/epidemiologia , Humanos , Modelos Logísticos , Masculino , Anamnese , Pessoa de Meia-Idade , Fatores de Risco , Suíça , Reino Unido/epidemiologia , Estados Unidos/epidemiologia , Vinho
4.
Alcohol Alcohol ; 56(1): 8-16, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-32869059

RESUMO

Chronic and excessive alcohol abuse cause direct and indirect detrimental effects on a wide range of body organs and systems and accounts for ~4% of deaths worldwide. Many factors influence the harmful effects of alcohol. This concise review presents newer insights into the role of select second hits in influencing the progression of alcohol-induced organ damage by synergistically acting to generate a more dramatic downstream biological defect. This review specifically addresses on how a lifestyle factor of high fat intake exacerbates alcoholic liver injury and its progression. This review also provides the mechanistic insights into how increasing matrix stiffness during liver injury promotes alcohol-induced fibrogenesis. It also discusses how hepatotropic viral (HCV, HBV) infections as well as HIV (which is traditionally not known to be hepatotropic), are potentiated by alcohol exposure to promote hepatotoxicity and fibrosis progression. Finally, this review highlights the impact of reactive aldehydes generated during alcohol and cigarette smoke coexposure impair innate antimicrobial defense and increased susceptibility to infections. This review was inspired by the symposium held at the 17th Congress of the European Society for Biomedical research on Alcoholism in Lille, France entitled 'Second hits in alcohol-related organ damage'.


Assuntos
Alcoolismo/complicações , Cirrose Hepática Alcoólica/etiologia , Alcoolismo/metabolismo , Fumar Cigarros/efeitos adversos , Fumar Cigarros/metabolismo , Dieta Hiperlipídica , Progressão da Doença , Suscetibilidade a Doenças , Infecções por HIV/complicações , Infecções por HIV/metabolismo , Hepatite B Crônica/complicações , Hepatite B Crônica/metabolismo , Hepatite C Crônica/complicações , Hepatite C Crônica/metabolismo , Humanos , Infecções , Cirrose Hepática Alcoólica/metabolismo , Hepatopatias Alcoólicas/etiologia , Hepatopatias Alcoólicas/metabolismo
5.
Adv Exp Med Biol ; 1032: 81-92, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30362092

RESUMO

Chronic ethanol consumption is a risk factor for several human cancers. A variety of mechanisms may contribute to this carcinogenic effect of alcohol including oxidative stress with the generation of reactive oxygen species (ROS), formed via inflammatory pathways or as byproducts of ethanol oxidation through cytochrome P4502E1 (CYP2E1). ROS may lead to lipidperoxidation (LPO) resulting in LPO-products such as 4-hydoxynonenal (4-HNE) or malondialdehyde. These compounds can react with DNA bases forming mutagenic and carcinogenic etheno-DNA adducts. Etheno-DNA adducts are generated in the liver (HepG2) cells over-expressing CYP2E1 when incubated with ethanol;and are inhibited by chlormethiazole. In liver biopsies etheno-DNA adducts correlated significantly with CYP2E1. Such a correlation was also found in the esophageal- and colorectal mucosa of alcoholics. Etheno-DNA adducts also increased in liver biopsies from patients with non alcoholic steatohepatitis (NASH). In various animal models with fatty liver either induced by high fat diets or genetically modified such as in the obese Zucker rat, CYP2E1 is induced and paralleled by high levels of etheno DNA-adducts which may be modified by additional alcohol administration. As elevation of adduct levels in NASH children were already detected at a young age, these lesions may contribute to hepatocellular cancer development later in life. Together these data strongly implicate CYP2E1 as an important mediator for etheno-DNA adduct formation, and this detrimental DNA damage may act as a driving force for malignant disease progression.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Citocromo P-450 CYP2E1/metabolismo , Adutos de DNA , Neoplasias Hepáticas/patologia , Aldeídos/metabolismo , Animais , Etanol/efeitos adversos , Fígado Gorduroso/patologia , Humanos , Peroxidação de Lipídeos , Malondialdeído/metabolismo , Ratos , Ratos Zucker , Espécies Reativas de Oxigênio/metabolismo
6.
Expert Opin Investig Drugs ; 27(8): 667-675, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30019966

RESUMO

INTRODUCTION: Alcoholic liver disease (ALD) is the leading cause of alcohol-related death and one of the most common forms of liver disease. Abstinence from alcohol is crucial to reducing morbidity and mortality associated with the disease. However, there are few pharmacotherapies for alcohol use disorder suitable for those with significant liver disease. AREAS COVERED: This paper presents a rationale for investigating the use of N-acetyl cysteine (NAC) to promote abstinence or reduce heavy alcohol consumption for patients with an alcohol use disorder, particularly in the presence of liver disease. NAC is an antioxidant with glutamatergic modulating and anti-inflammatory properties. Evidence is emerging that oxidative stress, neuro-inflammation and dysregulation of glutamatergic neurotransmission play a key role in alcohol use disorder. Similarly, oxidative stress is known to contribute to ALD. We outline the studies that have investigated NAC to reduce alcohol consumption including preclinical and clinical studies. We also review the evidence for NAC in other addictions as well as psychiatric and physical comorbidities associated with alcohol use disorders. EXPERT OPINION: NAC is low cost, well-tolerated and could have promise for the treatment of alcohol use disorder in the presence of liver disease. Clinical trials directly examining efficacy in this population are required.


Assuntos
Acetilcisteína/uso terapêutico , Alcoolismo/tratamento farmacológico , Antioxidantes/uso terapêutico , Acetilcisteína/efeitos adversos , Acetilcisteína/farmacologia , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/prevenção & controle , Alcoolismo/complicações , Alcoolismo/fisiopatologia , Animais , Antioxidantes/efeitos adversos , Antioxidantes/farmacologia , Humanos , Hepatopatias Alcoólicas/tratamento farmacológico , Hepatopatias Alcoólicas/fisiopatologia , Estresse Oxidativo/efeitos dos fármacos
7.
Am J Gastroenterol ; 110(6): 846-56, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25964223

RESUMO

OBJECTIVES: The genetic polymorphism with an isoleucine-to-methionine substitution at position 148 (rs738409 C>G) in the patatin-like phospholipase domain protein 3 (PNPLA3) gene confers risk of steatosis. PNPLA3 polymorphism is shown to be associated with alcoholic liver disease (ALD). We performed a systematic review and meta-analysis to examine association of this genetic polymorphism with ALD spectrum and its severity. METHODS: Medline, Embase, and Cochrane Library were searched for studies on association of PNPLA3 polymorphism and ALD spectrum: alcoholic fatty liver (AFL), alcoholic liver injury (ALI), alcoholic cirrhosis (AC), and hepatocellular carcinoma (HCC). Pooled data are reported as odds ratio (OR) with 95% confidence interval. Heterogeneity was assessed using the I(2) statistics and publication bias using Egger's test and Begg and Mazumdar's test. Individual participant data obtained from five studies were used for subgroup analyses. RESULTS: Among 10 studies included in this pooled analysis, compared with controls, OR for rs738409 CG and GG among ALI patients was 1.45 (1.24-1.69) and 2.22 (1.50-3.28), respectively, compared with CC. Respective OR among AC patients was 2.09 (1.79-2.44) and 3.37 (2.49-4.58) and among AC patients with HCC was 2.87 (1.61-5.10) and 12.41 (6.99-22.03). Data for AFL were inconsistent. Among ALD patients, OR of CG and GG genotypes was 2.62 (1.73-3.97) and 8.45 (2.52-28.37), respectively, for AC compared with fatty liver (FL) patients. Similar OR for AC compared with ALI was 1.98 (1.24-3.17) and 3.86 (1.18-12.60). The OR for CG and GG genotypes among AC patients for HCC occurrence was 1.43 (0.76-2.72) and 2.81 (1.57-5.01), respectively. Individual participant data analysis showed age to predispose to AC among ALI patients. CONCLUSIONS: PNPLA3 genetic polymorphism (rs738409 C>G) is associated with increased risk for the entire spectrum of ALD among drinkers including ALI, AC, and HCC. Studies are needed to clarify association of PNPLA3 polymorphism and steatosis in alcoholics. PNPLA3 gene may potentially be a therapeutic target in ALD.


Assuntos
Carcinoma Hepatocelular/genética , Doença Hepática Induzida por Substâncias e Drogas/genética , Fígado Gorduroso Alcoólico/genética , Lipase/genética , Cirrose Hepática Alcoólica/genética , Neoplasias Hepáticas/genética , Proteínas de Membrana/genética , Carcinoma Hepatocelular/induzido quimicamente , Depressores do Sistema Nervoso Central/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Etanol/efeitos adversos , Predisposição Genética para Doença , Humanos , Hepatopatias Alcoólicas/genética , Neoplasias Hepáticas/induzido quimicamente , Polimorfismo de Nucleotídeo Único , Índice de Gravidade de Doença
8.
World J Gastroenterol ; 20(36): 13088-104, 2014 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-25278703

RESUMO

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, αvß3-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.


Assuntos
Fígado Gorduroso Alcoólico/metabolismo , Células Estreladas do Fígado/metabolismo , Cirrose Hepática Alcoólica/metabolismo , Osteopontina/metabolismo , Animais , Estudos de Casos e Controles , Movimento Celular , Células Cultivadas , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fígado Gorduroso Alcoólico/genética , Fígado Gorduroso Alcoólico/patologia , Feminino , Fibrinolisina/metabolismo , Fibrinólise , Células Estreladas do Fígado/patologia , Humanos , Receptores de Hialuronatos/metabolismo , Integrina alfaVbeta3/metabolismo , Cirrose Hepática Alcoólica/genética , Cirrose Hepática Alcoólica/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteopontina/deficiência , Osteopontina/genética , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Mensageiro/metabolismo , Índice de Gravidade de Doença , Transdução de Sinais , Fatores de Tempo , Transfecção , Regulação para Cima
9.
Exp Mol Pathol ; 97(3): 492-510, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25217800

RESUMO

This paper is based upon the "Charles Lieber Satellite Symposia" organized by Manuela G. Neuman at the Research Society on Alcoholism (RSA) Annual Meetings, 2013 and 2014. The present review includes pre-clinical, translational and clinical research that characterize alcoholic liver disease (ALD) and non-alcoholic steatohepatitis (NASH). In addition, a literature search in the discussed area was performed. Strong clinical and experimental evidence lead to recognition of the key toxic role of alcohol in the pathogenesis of ALD. The liver biopsy can confirm the etiology of NASH or alcoholic steatohepatitis (ASH) and assess structural alterations of cells, their organelles, as well as inflammatory activity. Three histological stages of ALD are simple steatosis, ASH, and chronic hepatitis with hepatic fibrosis or cirrhosis. These latter stages may also be associated with a number of cellular and histological changes, including the presence of Mallory's hyaline, megamitochondria, or perivenular and perisinusoidal fibrosis. Genetic polymorphisms of ethanol metabolizing enzymes such as cytochrome p450 (CYP) 2E1 activation may change the severity of ASH and NASH. Alcohol mediated hepatocarcinogenesis, immune response to alcohol in ASH, as well as the role of other risk factors such as its co-morbidities with chronic viral hepatitis in the presence or absence of human immunodeficiency virus are discussed. Dysregulation of hepatic methylation, as result of ethanol exposure, in hepatocytes transfected with hepatitis C virus (HCV), illustrates an impaired interferon signaling. The hepatotoxic effects of ethanol undermine the contribution of malnutrition to the liver injury. Dietary interventions such as micro and macronutrients, as well as changes to the microbiota are suggested. The clinical aspects of NASH, as part of metabolic syndrome in the aging population, are offered. The integrative symposia investigate different aspects of alcohol-induced liver damage and possible repair. We aim to (1) determine the immuno-pathology of alcohol-induced liver damage, (2) examine the role of genetics in the development of ASH, (3) propose diagnostic markers of ASH and NASH, (4) examine age differences, (5) develop common research tools to study alcohol-induced effects in clinical and pre-clinical studies, and (6) focus on factors that aggravate severity of organ-damage. The intention of these symposia is to advance the international profile of the biological research on alcoholism. We also wish to further our mission of leading the forum to progress the science and practice of translational research in alcoholism.


Assuntos
Fígado Gorduroso , Hepatopatia Gordurosa não Alcoólica , Animais , Humanos
10.
FEBS Open Bio ; 4: 43-54, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24371721

RESUMO

The protease fibroblast activation protein (FAP) is a specific marker of activated mesenchymal cells in tumour stroma and fibrotic liver. A specific, reliable FAP enzyme assay has been lacking. FAP's unique and restricted cleavage of the post proline bond was exploited to generate a new specific substrate to quantify FAP enzyme activity. This sensitive assay detected no FAP activity in any tissue or fluid of FAP gene knockout mice, thus confirming assay specificity. Circulating FAP activity was ∼20- and 1.3-fold less in baboon than in mouse and human plasma, respectively. Serum and plasma contained comparable FAP activity. In mice, the highest levels of FAP activity were in uterus, pancreas, submaxillary gland and skin, whereas the lowest levels were in brain, prostate, leukocytes and testis. Baboon organs high in FAP activity included skin, epididymis, bladder, colon, adipose tissue, nerve and tongue. FAP activity was greatly elevated in tumours and associated lymph nodes and in fungal-infected skin of unhealthy baboons. FAP activity was 14- to 18-fold greater in cirrhotic than in non-diseased human liver, and circulating FAP activity was almost doubled in alcoholic cirrhosis. Parallel DPP4 measurements concorded with the literature, except for the novel finding of high DPP4 activity in bile. The new FAP enzyme assay is the first to be thoroughly characterised and shows that FAP activity is measurable in most organs and at high levels in some. This new assay is a robust tool for specific quantitation of FAP enzyme activity in both preclinical and clinical samples, particularly liver fibrosis.

11.
World J Gastroenterol ; 18(26): 3389-99, 2012 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-22807608

RESUMO

AIM: To investigate the role of osteopontin (OPN) and its splice variants in the proliferation of hepatocellular carcinoma (HCC). METHODS: The expression of OPN variants in HCC cell lines as well as HCC tissue samples and non-tumour tissue was studied using polymerase chain reaction. OPN variant cDNAs were cloned into a mammalian expression vector allowing both transient expression and the production of stable OPN expressing cell lines. OPN expression was studied in these cells using Western blotting, immunofluoresnce and enzyme linked immunosorbent assay. A CD44 blocking antibody and siRNA targeting of CD44 were used to examine the role of this receptor in the OPN stimulated cell growth observed in culture. Huh-7 cells stably expressing either OPN-A, -B or -C were injected subcutaneously into the flanks of nude mice to observe in vivo tumour growth. Expression of OPN mRNA and protein in these tumours was examined using reverse transcription-polymerase chain reaction and immunohistochemistry. RESULTS: OPN is expressed in HCC in 3 forms, the full length OPN-A and 2 splice variants OPN-B and -C. OPN variant expression was noted in HCC tissue as well as cognate surrounding cirrhotic liver tissue. Expression of these OPN variants in the HCC derived cell line Huh-7 resulted in secretion of OPN into the culture medium. Transfer of OPN conditioned media to naïve Huh-7 and HepG2 cells resulted in significant cell growth suggesting that all OPN variants can modulate cell proliferation in a paracrine manner. Furthermore the OPN mediated increase in cellular proliferation was dependent on CD44 as only CD44 positive cell lines responded to OPN conditioned media while siRNA knockdown of CD44 blocked the proliferative effect. OPN expression also increased the proliferation of Huh-7 cells in a subcutaneous nude mouse tumour model, with Huh-7 cells expressing OPN-A showing the greatest proliferative effect. CONCLUSION: This study demonstrates that OPN plays a significant role in the proliferation of HCC through interaction with the cell surface receptor CD44. Modulation of this interaction could represent a novel strategy for the control of HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Receptores de Hialuronatos/biossíntese , Neoplasias Hepáticas/metabolismo , Osteopontina/biossíntese , Animais , Linhagem Celular Tumoral , Proliferação de Células , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Vetores Genéticos , Humanos , Imuno-Histoquímica/métodos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias
12.
J Hepatol ; 48(4): 614-27, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18289715

RESUMO

BACKGROUND/AIMS: The pathogenesis of alcoholic liver disease (ALD) remains uncertain. Fibrin production and degradation are altered in experimental liver injury. We have recently identified increased expression of a number of genes (annexin A2 (ANXA2), p11, tPA and PAI-1) that implicate fibrinolysis in ALD progression. Aim of our study was to study the direct effect of alcohol on fibrinolysis and plasmin activity in hepatic cell lines and in vivo. METHODS: Expression of pro- and anti-fibrinolytic genes was determined in liver biopsies from patients with progressive ALD and in HepG2, Huh7 and LX-2 cells exposed to alcohol. The functional effects on fibrinolysis and plasmin activities were determined. C57BL6 female mice were given a single dose of alcohol and serum and liver triglyceride content and serum plasmin activity determined. RESULTS: Alcohol induced a significant up-regulation of ANXA2, PLG, PAI-1 and p11 in human ALD, cell lines and in mice exposed to alcohol. Up-regulation of ANXA2 and p11 was inhibited by the alcohol dehydrogenase inhibitor 4-methylpyrazole. Fibrinolysis and plasmin were increased in HepG2 and LX-2 cells by 10mM alcohol and was inhibited by ANXA2 blocking antibody. Plasmin also increased in mice given a moderate dose of alcohol. By contrast, there was striking up-regulation of PAI-1 in mice given a high dose of alcohol with associated decrease in plasmin. CONCLUSIONS: Alcohol directly alters hepatic expression of pro- and anti-fibrinolytic genes in a dose dependent manner with low dose promoting fibrinolysis and high dose inhibiting fibrinolysis. After a large dose of alcohol in vivo, the dominant effect was up-regulation of hepatic PAI-1 with suppression of plasmin. The effect of alcohol on fibrinolysis and plasmin is mediated in part by ANXA2. Alcohol directly influences hepatic pathways of fibrinolysis that may contribute to ALD.


Assuntos
Etanol/efeitos adversos , Fibrinólise/genética , Hepatopatias Alcoólicas/metabolismo , Fígado/metabolismo , RNA/genética , Regulação para Cima , Animais , Anexina A2/biossíntese , Anexina A2/genética , Antídotos/farmacologia , Biópsia , Linhagem Celular , Depressores do Sistema Nervoso Central/efeitos adversos , Modelos Animais de Doenças , Progressão da Doença , Feminino , Fibrinolisina/biossíntese , Fibrinolisina/genética , Fibrinólise/efeitos dos fármacos , Fomepizol , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Imuno-Histoquímica , Fígado/efeitos dos fármacos , Fígado/patologia , Hepatopatias Alcoólicas/genética , Hepatopatias Alcoólicas/patologia , Camundongos , Camundongos Endogâmicos C57BL , Fosfoproteínas/biossíntese , Fosfoproteínas/genética , Plasminogênio/biossíntese , Plasminogênio/genética , Inibidor 1 de Ativador de Plasminogênio/biossíntese , Inibidor 1 de Ativador de Plasminogênio/genética , Pirazóis/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ativador de Plasminogênio Tecidual/biossíntese , Ativador de Plasminogênio Tecidual/genética
13.
Dig Dis Sci ; 53(6): 1468-87, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17994278

RESUMO

Hepatitis C viral infection (HCV) results in liver damage leading to inflammation and fibrosis of the liver and increasing rates of hepatic decompensation and hepatocellular carcinoma (HCC). However, the host's immune response and viral determinants of liver disease progression are poorly understood. This review will address the determinants of liver injury in chronic HCV infection and the risk factors leading to rapid disease progression. We aim to better understand the factors that distinguish a relatively benign course of HCV from one with progression to cirrhosis. We will accomplish this task by discussion of three topics: (1) the role of cytokines in the adaptive immune response against the HCV infection; (2) the progression of fibrosis; and (3) the risk factors of co-morbidity with alcohol and human immunodeficiency virus (HIV) in HCV-infected individuals. Despite recent improvements in treating HCV infection using pegylated interferon alpha (PEGIFN-alpha) and ribavirin, about half of individuals infected with some genotypes, for example genotypes 1 and 4, will not respond to treatment or cannot be treated because of contraindications. This review will also aim to describe the importance of IFN-alpha-based therapies in HCV infection, ways of monitoring them, and associated complications.


Assuntos
Citocinas/imunologia , Hepatite C Crônica/complicações , Hepatite C Crônica/imunologia , Cirrose Hepática/virologia , Alcoolismo/complicações , Antivirais/uso terapêutico , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/virologia , Progressão da Doença , Genótipo , Infecções por HIV/complicações , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Humanos , Inflamação , Interferon-alfa/uso terapêutico , Cirrose Hepática/imunologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/virologia , Ribavirina/uso terapêutico , Fatores de Risco
14.
J Hepatol ; 45(2): 306-20, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16797773

RESUMO

BACKGROUND/AIMS: Alcoholic hepatitis remains an important cause of morbidity and mortality. Treatment remains unsatisfactory, in part, due to limited understanding of the pathogenesis. The aim of this study is to define the global intrahepatic expression profile of human alcoholic hepatitis. METHODS: Gene expression was analysed by DNA microarray on RNA isolated from liver of patients with alcoholic hepatitis (AH, n = 8), alcoholic steatosis (AS, n = 9) and explants from non-diseased donor liver controls (ND, n = 7). Differential expression of selected genes was confirmed by real-time RT-PCR and immunohistochemistry. RESULTS: Cluster analysis allowed differentiation of alcoholic hepatitis from alcoholic steatosis. The gene expression profile of AH revealed 586 genes differentially expressed from AS and 211 genes differentially expressed from that of ND liver. In comparison, only 98 genes were differentially expressed in AS from ND. Novel differentially expressed genes in AH in comparison to ND and AS included claudins, osteopontin, CD209, selenoprotein and genes related to bile duct proliferation. Real-time RT-PCR confirmed up-regulation of IL-8, osteopontin, and TNFRSF14 and down-regulation of SAMeS and CD209. CONCLUSIONS: This study has defined the intrahepatic gene expression profile of human alcoholic hepatitis and revealed a number of novel differentially expressed genes.


Assuntos
Expressão Gênica , Hepatite Alcoólica/genética , RNA/genética , Adulto , Idoso , Anexina A2/genética , Biópsia , Moléculas de Adesão Celular/genética , Feminino , Hepatite Alcoólica/metabolismo , Hepatite Alcoólica/patologia , Humanos , Interleucina-8/genética , Lectinas Tipo C/genética , Masculino , Análise em Microsséries , Pessoa de Meia-Idade , Osteopontina/genética , Receptores de Superfície Celular/genética , Membro 14 de Receptores do Fator de Necrose Tumoral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Adv Exp Med Biol ; 575: 45-54, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16700507
16.
J Gastroenterol Hepatol ; 18(12): 1332-44, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14675260

RESUMO

Alcoholic hepatitis is a potentially life-threatening complication of alcoholic abuse, typically presenting with symptoms and signs of hepatitis in the presence of an alcohol use disorder. The definitive diagnosis requires liver biopsy, but this is not generally required. The pathogenesis is uncertain, but relevant factors include metabolism of alcohol to toxic products, oxidant stress, acetaldehyde adducts, the action of endotoxin on Kupffer cells, and impaired hepatic regeneration. Mild alcoholic hepatitis recovers with abstinence and the long-term prognosis is determined by the underlying disorder of alcohol use. Severe alcoholic hepatitis is recognized by a Maddrey discriminant function >32 and is associated with a short-term mortality rate of almost 50%. Primary therapy is abstinence from alcohol and supportive care. Corticosteroids have been shown to be beneficial in a subset of severely ill patients with concomitant hepatic encephalopathy, but their use remains controversial. Pentoxifylline has been shown in one study to improve short-term survival rates. Other pharmacological interventions, including colchicine, propylthiouracil, calcium channel antagonists, and insulin with glucagon infusions, have not been proven to be beneficial. Nutritional supplementation with available high-calorie, high-protein diets is beneficial, but does not improve mortality. Orthotopic liver transplantation is not indicated for patients presenting with alcoholic hepatitis who have been drinking until the time of admission, but may be considered in those who achieve stable abstinence if liver function fails to recover.


Assuntos
Hepatite Alcoólica/etiologia , Hepatite Alcoólica/terapia , Hepatite Alcoólica/fisiopatologia , Humanos , Fígado/metabolismo , Fígado/patologia , Fígado/fisiopatologia
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