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1.
Ann Hepatol ; : 101528, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38971372

RESUMO

INTRODUCTION AND OBJECTIVES: Despite the huge clinical burden of MASLD, validated tools for early risk stratification are lacking, and heterogeneous disease expression and a highly variable rate of progression to clinical outcomes result in prognostic uncertainty. We aimed to investigate longitudinal electronic health record-based outcome prediction in MASLD using a state-of-the-art machine learning model. PATIENTS AND METHODS: n=940 patients with histologically-defined MASLD were used to develop a deep-learning model for all-cause mortality prediction. Patient timelines, spanning 12 years, were fully-annotated with demographic/clinical characteristics, ICD-9 and -10 codes, blood test results, prescribing data, and secondary care activity. A Transformer neural network (TNN) was trained to output concomitant probabilities of 12-, 24-, and 36-month all-cause mortality. In-sample performance was assessed using 5-fold cross-validation. Out-of-sample performance was assessed in an independent set of n=528 MASLD patients. RESULTS: In-sample model performance achieved AUROC curve 0.74-0.90 (95% CI: 0.72-0.94), sensitivity 64%-82%, specificity 75%-92% and Positive Predictive Value (PPV) 94%-98%. Out-of-sample model validation had AUROC 0.70-0.86 (95% CI: 0.67-0.90), sensitivity 69%-70%, specificity 96%-97% and PPV 75%-77%. Key predictive factors, identified using coefficients of determination, were age, presence of type 2 diabetes, and history of hospital admissions with length of stay >14 days. CONCLUSIONS: A TNN, applied to routinely-collected longitudinal electronic health records, achieved good performance in prediction of 12-, 24-, and 36-month all-cause mortality in patients with MASLD. Extrapolation of our technique to population-level data will enable scalable and accurate risk stratification to identify people most likely to benefit from anticipatory health care and personalized interventions.

2.
Ann Hepatol ; 29(2): 101278, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38135251

RESUMO

Metabolic dysfunction-associated steatotic liver disease (MASLD), defined by the presence of liver steatosis together with at least one out of five cardiometabolic factors, is the most common cause of chronic liver disease worldwide, affecting around one in three people. Yet the clinical presentation of MASLD and the risk of progression to cirrhosis and adverse clinical outcomes is highly variable. It, therefore, represents both a global public health threat and a precision medicine challenge. Artificial intelligence (AI) is being investigated in MASLD to develop reproducible, quantitative, and automated methods to enhance patient stratification and to discover new biomarkers and therapeutic targets in MASLD. This review details the different applications of AI and machine learning algorithms in MASLD, particularly in analyzing electronic health record, digital pathology, and imaging data. Additionally, it also describes how specific MASLD consortia are leveraging multimodal data sources to spark research breakthroughs in the field. Using a new national-level 'data commons' (SteatoSITE) as an exemplar, the opportunities, as well as the technical challenges of large-scale databases in MASLD research, are highlighted.


Assuntos
Fígado Gorduroso , Doenças Metabólicas , Humanos , Inteligência Artificial , Algoritmos , Bases de Dados Factuais
3.
Hepatology ; 75(5): 1081-1094, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34651315

RESUMO

BACKGROUND AND AIMS: Genome-wide association studies (GWAS) have identified several risk loci for gallstone disease. As with most polygenic traits, it is likely that many genetic determinants are undiscovered. The aim of this study was to identify genetic variants that represent new targets for gallstone research and treatment. APPROACH AND RESULTS: We performed a GWAS of 28,627 gallstone cases and 348,373 controls in the UK Biobank, replicated findings in a Scottish cohort (1089 cases, 5228 controls), and conducted a GWA meta-analysis (43,639 cases, 506,798 controls) with the FinnGen cohort. We assessed pathway enrichment using gene-based then gene-set analysis and tissue expression of identified genes in Genotype-Tissue Expression project data. We constructed a polygenic risk score (PRS) and evaluated phenotypic traits associated with the score. Seventy-five risk loci were identified (p < 5 × 10-8 ), of which 46 were new. Pathway enrichment revealed associations with lipid homeostasis, glucuronidation, phospholipid metabolism, and gastrointestinal motility. Anoctamin 1 (ANO1) and transmembrane Protein 147 (TMEM147), both in novel, replicated loci, are expressed in the gallbladder and gastrointestinal tract. Both regulate gastrointestinal motility. The gallstone risk allele rs7599-A leads to suppression of hepatic TMEM147 expression, suggesting that the protein protects against gallstone formation. The highest decile of the PRS demonstrated a 6-fold increased odds of gallstones compared with the lowest decile. The PRS was strongly associated with increased body mass index, serum liver enzymes, and C-reactive protein concentrations, and decreased lipoprotein cholesterol concentrations. CONCLUSIONS: This GWAS demonstrates the polygenic nature of gallstone risk and identifies 46 novel susceptibility loci. We implicate genes influencing gastrointestinal motility in the pathogenesis of gallstones.


Assuntos
Cálculos Biliares , Estudo de Associação Genômica Ampla , Cálculos Biliares/genética , Cálculos Biliares/metabolismo , Motilidade Gastrointestinal , Predisposição Genética para Doença/genética , Humanos , Polimorfismo de Nucleotídeo Único , População Branca
4.
Clin Gastroenterol Hepatol ; 20(11): 2451-2461.e3, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34626833

RESUMO

BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD) is increasing in prevalence worldwide. NAFLD is associated with excess risk of all-cause mortality, and its progression to nonalcoholic steatohepatitis (NASH) and fibrosis accounts for a growing proportion of cirrhosis and hepatocellular cancer and thus is a leading cause of liver transplant worldwide. Noninvasive precise methods to identify patients with NASH and NASH with significant disease activity and fibrosis are crucial when the disease is still modifiable. The aim of this study was to examine the clinical utility of corrected T1 (cT1) vs magnetic resonance imaging (MRI) liver fat for identification of NASH participants with nonalcoholic fatty liver disease activity score ≥4 and fibrosis stage (F) ≥2 (high-risk NASH). METHODS: Data from five clinical studies (n = 543) with participants suspected of NAFLD were pooled or used for individual participant data meta-analysis. The diagnostic accuracy of the MRI biomarkers to stratify NASH patients was determined using the area under the receiver operating characteristic curve (AUROC). RESULTS: A stepwise increase in cT1 and MRI liver fat with increased NAFLD severity was shown, and cT1 was significantly higher in participants with high-risk NASH. The diagnostic accuracy (AUROC) of cT1 to identify patients with NASH was 0.78 (95% CI, 0.74-0.82), for liver fat was 0.78 (95% CI, 0.73-0.82), and when combined with MRI liver fat was 0.82 (95% CI, 0.78-0.85). The diagnostic accuracy of cT1 to identify patients with high-risk NASH was good (AUROC = 0.78; 95% CI, 0.74-0.82), was superior to MRI liver fat (AUROC = 0.69; 95% CI, 0.64-0.74), and was not substantially improved by combining it with MRI liver fat (AUROC = 0.79; 95% CI, 0.75-0.83). The meta-analysis showed similar performance to the pooled analysis for these biomarkers. CONCLUSIONS: This study shows that quantitative MRI-derived biomarkers cT1 and liver fat are suitable for identifying patients with NASH, and cT1 is a better noninvasive technology than liver fat to identify NASH patients at greatest risk of disease progression. Therefore, MRI cT1 and liver fat have important clinical utility to help guide the appropriate use of interventions in NAFLD and NASH clinical care pathways.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/diagnóstico , Imageamento por Ressonância Magnética/métodos , Biomarcadores , Estudos Multicêntricos como Assunto
5.
J Hepatol ; 75(2): 439-441, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33905793

RESUMO

BACKGROUND & AIMS: The development of COVID-19 vaccines has progressed with encouraging safety and efficacy data. Concerns have been raised about SARS-CoV-2 vaccine responses in the large population of patients with non-alcoholic fatty liver disease (NAFLD). The study aimed to explore the safety and immunogenicity of COVID-19 vaccination in NAFLD. METHODS: This multicenter study included patients with NAFLD without a history of SARS-CoV-2 infection. All patients were vaccinated with 2 doses of inactivated vaccine against SARS-CoV-2. The primary safety outcome was the incidence of adverse reactions within 7 days after each injection and overall incidence of adverse reactions within 28 days, and the primary immunogenicity outcome was neutralizing antibody response at least 14 days after the whole-course vaccination. RESULTS: A total of 381 patients with pre-existing NAFLD were included from 11 designated centers in China. The median age was 39.0 years (IQR 33.0-48.0 years) and 179 (47.0%) were male. The median BMI was 26.1 kg/m2 (IQR 23.8-28.1 kg/m2). The number of adverse reactions within 7 days after each injection and adverse reactions within 28 days totaled 95 (24.9%) and 112 (29.4%), respectively. The most common adverse reactions were injection site pain in 70 (18.4%), followed by muscle pain in 21 (5.5%), and headache in 20 (5.2%). All adverse reactions were mild and self-limiting, and no grade 3 adverse reactions were recorded. Notably, neutralizing antibodies against SARS-CoV-2 were detected in 364 (95.5%) patients with NAFLD. The median neutralizing antibody titer was 32 (IQR 8-64), and the neutralizing antibody titers were maintained. CONCLUSIONS: The inactivated COVID-19 vaccine appears to be safe with good immunogenicity in patients with NAFLD. LAY SUMMARY: The development of vaccines against coronavirus disease 2019 (COVID-19) has progressed rapidly, with encouraging safety and efficacy data. This study now shows that the inactivated COVID-19 vaccine appears to be safe with good immunogenicity in the large population of patients with non-alcoholic fatty liver disease.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19 , Imunogenicidade da Vacina/imunologia , Hepatopatia Gordurosa não Alcoólica , Vacinação , Vacinas de Produtos Inativados , Adulto , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/efeitos adversos , China/epidemiologia , Feminino , Humanos , Masculino , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Avaliação de Resultados em Cuidados de Saúde , SARS-CoV-2/imunologia , Vacinação/efeitos adversos , Vacinação/métodos , Vacinação/estatística & dados numéricos , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/efeitos adversos
6.
BMC Public Health ; 21(1): 970, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34154561

RESUMO

BACKGROUND: Chronic liver disease (CLD) is a growing cause of morbidity and mortality worldwide, particularly in low to middle-income countries with high disease burden and limited treatment availability. Coffee consumption has been linked with lower rates of CLD, but little is known about the effects of different coffee types, which vary in chemical composition. This study aimed to investigate associations of coffee consumption, including decaffeinated, instant and ground coffee, with chronic liver disease outcomes. METHODS: A total of 494,585 UK Biobank participants with known coffee consumption and electronic linkage to hospital, death and cancer records were included in this study. Cox regression was used to estimate hazard ratios (HR) of incident CLD, incident CLD or steatosis, incident hepatocellular carcinoma (HCC) and death from CLD according to coffee consumption of any type as well as for decaffeinated, instant and ground coffee individually. RESULTS: Among 384,818 coffee drinkers and 109,767 non-coffee drinkers, there were 3600 cases of CLD, 5439 cases of CLD or steatosis, 184 cases of HCC and 301 deaths from CLD during a median follow-up of 10.7 years. Compared to non-coffee drinkers, coffee drinkers had lower adjusted HRs of CLD (HR 0.79, 95% CI 0.72-0.86), CLD or steatosis (HR 0.80, 95% CI 0.75-0.86), death from CLD (HR 0.51, 95% CI 0.39-0.67) and HCC (HR 0.80, 95% CI 0.54-1.19). The associations for decaffeinated, instant and ground coffee individually were similar to all types combined. CONCLUSION: The finding that all types of coffee are protective against CLD is significant given the increasing incidence of CLD worldwide and the potential of coffee as an intervention to prevent CLD onset or progression.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Bancos de Espécimes Biológicos , Carcinoma Hepatocelular/epidemiologia , Café , Humanos , Neoplasias Hepáticas/epidemiologia , Estudos Prospectivos , Fatores de Risco , Reino Unido/epidemiologia
7.
Am J Kidney Dis ; 75(5): 753-761, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31837886

RESUMO

RATIONALE & OBJECTIVE: Chronic kidney disease (CKD) is a leading cause of morbidity and mortality worldwide, with limited strategies for prevention and treatment. Coffee is a complex mixture of chemicals, and consumption has been associated with mostly beneficial health outcomes. This work aimed to determine the impact of coffee consumption on kidney function. STUDY DESIGN: Genome-wide association study (GWAS) and Mendelian randomization. SETTING & PARTICIPANTS: UK Biobank baseline data were used for a coffee consumption GWAS and included 227,666 participants. CKDGen Consortium data were used for kidney outcomes and included 133,814 participants (12,385 cases of CKD) of mostly European ancestry across various countries. EXPOSURE: Coffee consumption. OUTCOMES: Estimated glomerular filtration rate (eGFR), CKD GFR categories 3 to 5 (G3-G5; eGFR<60mL/min/1.73m2), and albuminuria. ANALYTICAL APPROACH: GWAS to identify single-nucleotide polymorphisms (SNPs) associated with coffee consumption in UK Biobank and use of those SNPs in Mendelian randomization analyses of coffee consumption and kidney outcomes in CKDGen. RESULTS: 2,126 SNPs were associated with coffee consumption (P<5×10-8), 25 of which were independent and available in CKDGen. Drinking an extra cup of coffee per day conferred a protective effect against CKD G3-G5 (OR, 0.84; 95% CI, 0.72-0.98; P=0.03) and albuminuria (OR, 0.81; 95% CI, 0.67-0.97; P=0.02). An extra cup was also associated with higher eGFR (ß=0.022; P=1.6×10-6) after removal of 3 SNPs responsible for significant heterogeneity (Cochran Q P = 3.5×10-15). LIMITATIONS: Assays used to measure creatinine and albumin varied between studies that contributed data and a sex-specific definition was used for albuminuria rather than KDIGO guideline recommendations. CONCLUSIONS: This study provides evidence of a beneficial effect of coffee on kidney function. Given widespread coffee consumption and limited interventions to prevent CKD incidence and progression, this could have significant implications for global public health in view of the increasing burden of CKD worldwide.


Assuntos
Café , Rim/efeitos dos fármacos , Albuminúria/epidemiologia , Albuminúria/genética , Causalidade , Fatores de Confusão Epidemiológicos , Creatinina/sangue , Relação Dose-Resposta a Droga , Comportamento de Ingestão de Líquido , Estudo de Associação Genômica Ampla , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Rim/fisiologia , Nefropatias/genética , Nefropatias/prevenção & controle , Estudos Observacionais como Assunto , Polimorfismo de Nucleotídeo Único , Caracteres Sexuais , Reino Unido/epidemiologia
8.
Liver Int ; 40(9): 2252-2262, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32638496

RESUMO

BACKGROUND: The incidence of cirrhosis and hepatocellular carcinoma (HCC) is increased in Type 2 diabetes, primarily secondary to non-alcoholic fatty liver disease (NAFLD). European guidelines recommend screening for NAFLD in Type 2 diabetes. American guidelines, while not advocating a screening protocol, suggest using non-invasive markers of fibrosis for risk-stratification and guiding onward referral. AIMS: To test the ability of individual fibrosis scores and the European screening algorithm to predict 11-year incident cirrhosis/HCC in an asymptomatic community cohort of older people with Type 2 diabetes. METHODS: The Edinburgh Type 2 Diabetes Study investigated men and women with Type 2 diabetes (n = 1066, aged 60-75 at baseline). Liver markers were measured at baseline and year 1; steatosis and fibrosis markers were calculated according to independently published calculations. During 11 years of follow-up, cases of cirrhosis and HCC were identified. RESULTS: Forty-three out of 1059 participants with no baseline cirrhosis/HCC developed incident disease. All scores were significantly associated with incident liver disease by odds ratio (P < .05). The ability of the risk-stratification tools to accurately identify those who developed incident cirrhosis/HCC was poor with low-positive predictive values (5-46%) and high false-negative and -positive rates (up to 60% and 77%) respectively. When fibrosis risk scores were used in conjunction with the European algorithm, they performed modestly better than when applied in isolation. CONCLUSIONS: In a cohort with a moderately low incidence of cirrhosis/HCC, existing risk scores did not reliably identify participants at high risk. Better prediction models for cirrhosis/HCC in people with Type 2 diabetes are required.


Assuntos
Carcinoma Hepatocelular , Diabetes Mellitus Tipo 2 , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Idoso , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Incidência , Cirrose Hepática/diagnóstico , Cirrose Hepática/epidemiologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Estudos Retrospectivos , Fatores de Risco
10.
Histopathology ; 73(1): 90-100, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29464815

RESUMO

AIMS: The aim of this study was to determine if elastin content in needle core native liver biopsies was predictive of clinical outcome in patients with chronic hepatitis C virus-related chronic liver disease. METHODS AND RESULTS: Elastin contents in liver biopsies were determined by image analysis, technically validated in an independent centre, and correlated with outcome in patients with advanced (Ishak stage ≥5) chronic hepatitis C virus-related chronic liver disease. Elastin was robustly quantified in an operator-independent and laboratory-independent manner, with very strong correlation of elastin staining measured with two methods of image classification (rs = 0.873, P < 0.00001). Elastin content (but not absolute scar content or Ishak stage) was predictive for future clinical outcomes. In a cohort of patients without sustained virological response, the median hepatic elastin content was 3.4%, and 17 patients (57%) progressed to a liver-related clinical outcome; 11 of the 15 patients (73%) with a hepatic elastin content of >3.4% progressed to a clinical outcome, as compared with only six of 15 (40%) with an elastin content of <3.4%. The difference in time to outcome was significant. CONCLUSIONS: We describe a simple and reproducible method for elastin quantification in liver biopsies that provides potentially valuable prognostic information to inform clinical management.


Assuntos
Elastina/análise , Hepatite C Crônica/patologia , Cirrose Hepática/patologia , Adulto , Biópsia com Agulha de Grande Calibre , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
11.
BMC Cancer ; 18(1): 890, 2018 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-30208871

RESUMO

BACKGROUND: Accurate assessment of liver health prior to undertaking resectional liver surgery or chemoembolisation for primary and secondary cancers is essential for patient safety and optimal outcomes. LiverMultiScan™, an MRI-based technology, non-invasively quantifies hepatic fibroinflammatory disease, steatosis and iron content. We hypothesise that LiverMultiScan™can quantify liver health prior to surgery and inform the risk assessment for patients considering liver surgery or chemoembolization and seek to evaluate this technology in an operational environment. METHODS/DESIGN: HepaT1ca is an observational cohort study in two tertiary-referral liver surgery centres in the United Kingdom. The primary outcome is correlation between the pre-operative liver health assessment score (Hepatica score - calculated by weighting future remnant liver volume by liver inflammation and fibrosis (LIF) score) and the post-operative liver function composite integer-based risk (Hyder-Pawlik) score. With ethical approval and fully-informed consent, individuals considering liver surgery for primary or secondary cancer will undergo clinical assessment, blood sampling, and LiverMultiScan™multiparametric MRI before and after surgical liver resection or TACE. In nested cohorts of individuals undergoing chemotherapy prior to surgery, or those undergoing portal vein embolization (PVE) as an adjunct to surgery, an additional testing session prior to commencement of treatment will occur. Tissue will be examined histologically and by immunohistochemistry. Pre-operative liver health assessment scores and the post-operative risk scores will be correlated to define the ability of LiverMultiScan™to predict the risk of post-operative morbidity and mortality. Because technology performance in this setting is unknown, a pragmatic sample size will be used. For the primary outcome, n = 200 for the main cohort will allow detection of a minimum correlation coefficient of 0.2 with 5% significance and power of 80%. DISCUSSION: This study will refine the technology and clinical application of multiparametric MRI (including LiverMultiScan™), to quantify pre-existing liver health and predict post-intervention outcomes following liver resection. If successful, this study will advance the technology and support the use of multiparametric MRI as part of an enhanced pre-operative assessment to improve patient safety and to personalise operative risk assessment of liver surgery/non-surgical intervention. TRIAL REGISTRATION: This study is registered on ClinicalTrials.gov Identifier: NCT03213314 .


Assuntos
Protocolos Clínicos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/metabolismo , Fígado/metabolismo , Cuidados Pré-Operatórios , Ensaios Clínicos como Assunto , Gerenciamento Clínico , Humanos , Fígado/patologia , Fígado/cirurgia , Testes de Função Hepática , Neoplasias Hepáticas/cirurgia , Imageamento por Ressonância Magnética
12.
PLoS Med ; 14(2): e1002248, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28245243

RESUMO

BACKGROUND: Chronic liver scarring from any cause leads to cirrhosis, portal hypertension, and a progressive decline in renal blood flow and renal function. Extreme renal vasoconstriction characterizes hepatorenal syndrome, a functional and potentially reversible form of acute kidney injury in patients with advanced cirrhosis, but current therapy with systemic vasoconstrictors is ineffective in a substantial proportion of patients and is limited by ischemic adverse events. Serelaxin (recombinant human relaxin-2) is a peptide molecule with anti-fibrotic and vasoprotective properties that binds to relaxin family peptide receptor-1 (RXFP1) and has been shown to increase renal perfusion in healthy human volunteers. We hypothesized that serelaxin could ameliorate renal vasoconstriction and renal dysfunction in patients with cirrhosis and portal hypertension. METHODS AND FINDINGS: To establish preclinical proof of concept, we developed two independent rat models of cirrhosis that were characterized by progressive reduction in renal blood flow and glomerular filtration rate and showed evidence of renal endothelial dysfunction. We then set out to further explore and validate our hypothesis in a phase 2 randomized open-label parallel-group study in male and female patients with alcohol-related cirrhosis and portal hypertension. Forty patients were randomized 1:1 to treatment with serelaxin intravenous (i.v.) infusion (for 60 min at 80 µg/kg/d and then 60 min at 30 µg/kg/d) or terlipressin (single 2-mg i.v. bolus), and the regional hemodynamic effects were quantified by phase contrast magnetic resonance angiography at baseline and after 120 min. The primary endpoint was the change from baseline in total renal artery blood flow. Therapeutic targeting of renal vasoconstriction with serelaxin in the rat models increased kidney perfusion, oxygenation, and function through reduction in renal vascular resistance, reversal of endothelial dysfunction, and increased activation of the AKT/eNOS/NO signaling pathway in the kidney. In the randomized clinical study, infusion of serelaxin for 120 min increased total renal arterial blood flow by 65% (95% CI 40%, 95%; p < 0.001) from baseline. Administration of serelaxin was safe and well tolerated, with no detrimental effect on systemic blood pressure or hepatic perfusion. The clinical study's main limitations were the relatively small sample size and stable, well-compensated population. CONCLUSIONS: Our mechanistic findings in rat models and exploratory study in human cirrhosis suggest the therapeutic potential of selective renal vasodilation using serelaxin as a new treatment for renal dysfunction in cirrhosis, although further validation in patients with more advanced cirrhosis and renal dysfunction is required. TRIAL REGISTRATION: ClinicalTrials.gov NCT01640964.


Assuntos
Nefropatias/tratamento farmacológico , Rim/efeitos dos fármacos , Cirrose Hepática/tratamento farmacológico , Relaxina/farmacologia , Relaxina/uso terapêutico , Adolescente , Adulto , Idoso , Animais , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Rim/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Fluxo Sanguíneo Regional/efeitos dos fármacos , Escócia , Adulto Jovem
13.
Dig Dis ; 35(4): 310-313, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28467988

RESUMO

BACKGROUND: Liver fibrosis is the final common pathway of iterative or chronic liver damage. When it reaches an advanced stage, cirrhosis develops and this indicates a loss of normal liver architecture, disruption of normal blood flow, the development of nodules of proliferative hepatocytes and consequent functional failure. Cirrhosis is also associated with life-threatening complications. Importantly, this dysregulation of blood flow involves changes resulting from both architectural disruption and a dynamic rise in portal pressure mediated in part by the contraction of myofibroblasts - the major cell mediator of the fibrogenic process - which are derived from hepatic stellate cells (HSC) and termed activated HSC (myofibroblast/activated HSC). Key Messages: There is now compelling data from both rodent and human models that liver fibrosis is bidirectional. By studying models of progressive and regressing liver fibrosis it has been possible to identify mediators that may be therapeutic targets. Arguably, by identifying the mediators of spontaneous resolution that result in a return of normal architecture, the attributes of a highly effective antifibrotic or pro resolution therapy can be defined. Among these key attributes, understanding the balance of matrix-degrading enzymes and their inhibitors (the metalloproteinases and Tissue inhibitors of metalloproteinases (TIMPs), respectively) led to the identification of both therapeutic targets and the value of TIMP-1 as a serum marker of fibrosis. Furthermore, the action of a potential therapeutic agent, relaxin (RLN) acting through its cognate G-protein coupled receptor (RXFP1) on the surface of activated HSC shows promise. Activation of the RLN-RXFP1-mediated pathway can be detected in vivo by measuring the dynamic contractility of activated HSC and the consequent changes in portal pressure and blood flow as a responsive physical biomarker. CONCLUSION: By understanding progressive and resolving liver fibrosis, a series of therapeutic targets have been identified. At the same time, key mediators of fibrosis may have an integral role to play as soluble or physical biomarkers.


Assuntos
Biomarcadores/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/terapia , Animais , Humanos , Cirrose Hepática/metabolismo , Terapia de Alvo Molecular , Miofibroblastos/patologia , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/metabolismo , Relaxina/metabolismo
15.
Semin Liver Dis ; 35(2): 119-31, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25974898

RESUMO

With evidence from a large number of animal models and clinical trials, it is now beyond debate that liver fibrosis and even cirrhosis are potentially reversible if the underlying cause can be successfully eliminated. However, in a significant proportion of patients cure of the underlying disease may not result in fibrosis regression or a significant reduction of the risk for hepatocellular carcinoma development. Understanding of the mechanistic pathways and regulatory factors that characterize matrix remodeling and architectural repair during fibrosis regression may provide therapeutic approaches to induce or accelerate regression as well as novel diagnostic tools. Recent seminal observations have determined that in resolving liver fibrosis a significant proportion of hepatic stellate cell-myofibroblasts (HSC-MFs) can revert to a near quiescent phenotype. Hepatic macrophages derived from inflammatory monocytes may contribute to fibrosis resolution through an in situ phenotypic switch mediated by phagocytosis. Emerging therapeutic approaches include deletion or inactivation of HSC-MFs, modulation of macrophage activity and autologous cell infusion therapies. Novel noninvasive diagnostic tests such as serum and imaging markers responsive to extracellular matrix degradation are being developed to evaluate the clinical efficacy of antifibrotic interventions.


Assuntos
Células Estreladas do Fígado/patologia , Cirrose Hepática/patologia , Recuperação de Função Fisiológica , Animais , Células Estreladas do Fígado/metabolismo , Humanos , Cirrose Hepática/metabolismo , Transdução de Sinais
16.
Diabetologia ; 58(7): 1484-93, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25820150

RESUMO

AIMS/HYPOTHESIS: We examined the association of prevalent and incident cardiovascular disease (CVD) with chronic liver disease in a cohort of community-based people with type 2 diabetes, in order to clarify the relationship between these two important conditions. METHODS: 1,066 participants with type 2 diabetes aged 60-75 years underwent assessment of a range of liver injury markers (non-specific injury, steatosis, steatohepatitis, fibrosis, portal hypertension). Individuals were followed up for incident cardiovascular events. RESULTS: At baseline there were 370/1,033 patients with prevalent CVD, including 317/1,033 with coronary artery disease (CAD). After a mean follow-up of 4.4 years there were 44/663 incident CVD events, including 27/663 CAD events. There were 30/82 CVD-related deaths. Risk of dying from or developing CVD was no higher in participants with steatosis than in those without (HR 0.90; 95% CI 0.40, 2.00; p > 0.05). The only notable relationship was with γ-glutamyltransferase (GGT) (incident CVD: adjusted HR for doubling GGT 1.24 [95% CI 0.97, 1.59] p = 0.086; incident CAD: adjusted HR 1.33 [95% CI 1.00, 1.78] p = 0.053), suggesting that in our study population, chronic liver disease may have little effect on the development of, or mortality from, CVD. CONCLUSIONS/INTERPRETATION: An independent association between GGT and CVD warrants further exploration as a potentially useful addition to current cardiovascular risk prediction models in diabetes. However, overall findings failed to suggest that there is a clinical or pathophysiological association between chronic liver disease and CVD in elderly people with type 2 diabetes.


Assuntos
Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Cirrose Hepática/sangue , gama-Glutamiltransferase/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Doenças Cardiovasculares/enzimologia , Doença Crônica , Doença da Artéria Coronariana/epidemiologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/enzimologia , Fígado Gorduroso/epidemiologia , Feminino , Humanos , Testes de Função Hepática , Masculino , Escócia/epidemiologia , Resultado do Tratamento
17.
Hepatology ; 59(4): 1492-504, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23873655

RESUMO

UNLABELLED: Active myofibroblast (MF) contraction contributes significantly to the increased intrahepatic vascular resistance that is the primary cause of portal hypertension (PHT) in cirrhosis. We sought proof of concept for direct therapeutic targeting of the dynamic component of PHT and markers of MF activation using short-term administration of the peptide hormone relaxin (RLN). We defined the portal hypotensive effect in rat models of sinusoidal PHT and the expression, activity, and function of the RLN-receptor signaling axis in human liver MFs. The effects of RLN were studied after 8 and 16 weeks carbon tetrachloride intoxication, following bile duct ligation, and in tissue culture models. Hemodynamic changes were analyzed by direct cannulation, perivascular flowprobe, indocyanine green imaging, and functional magnetic resonance imaging. Serum and hepatic nitric oxide (NO) levels were determined by immunoassay. Hepatic inflammation was assessed by histology and serum markers and fibrosis by collagen proportionate area. Gene expression was analyzed by quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and western blotting and hepatic stellate cell (HSC)-MF contractility by gel contraction assay. Increased expression of RLN receptor (RXFP1) was shown in HSC-MFs and fibrotic liver diseases in both rats and humans. RLN induced a selective and significant reduction in portal pressure in pathologically distinct PHT models, through augmentation of intrahepatic NO signaling and a dramatic reduction in contractile filament expression in HSC-MFs. Critical for translation, RLN did not induce systemic hypotension even in advanced cirrhosis models. Portal blood flow and hepatic oxygenation were increased by RLN in early cirrhosis. Treatment of human HSC-MFs with RLN inhibited contractility and induced an antifibrogenic phenotype in an RXFP1-dependent manner. CONCLUSION: We identified RXFP1 as a potential new therapeutic target for PHT and MF activation status.


Assuntos
Hipertensão Portal/prevenção & controle , Cirrose Hepática/prevenção & controle , Fígado/efeitos dos fármacos , Miofibroblastos/efeitos dos fármacos , Relaxina/farmacologia , Relaxina/uso terapêutico , Actinas/metabolismo , Animais , Tetracloreto de Carbono/efeitos adversos , Células Cultivadas , Desmina/metabolismo , Modelos Animais de Doenças , Proteína Glial Fibrilar Ácida/metabolismo , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Humanos , Hipertensão Portal/induzido quimicamente , Hipertensão Portal/fisiopatologia , Fígado/metabolismo , Fígado/fisiopatologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/fisiopatologia , Masculino , Miofibroblastos/patologia , Miofibroblastos/fisiologia , Óxido Nítrico/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Peptídeos/metabolismo , Relaxina/metabolismo
18.
Proc Natl Acad Sci U S A ; 109(46): E3186-95, 2012 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-23100531

RESUMO

Although macrophages are widely recognized to have a profibrotic role in inflammation, we have used a highly tractable CCl(4)-induced model of reversible hepatic fibrosis to identify and characterize the macrophage phenotype responsible for tissue remodeling: the hitherto elusive restorative macrophage. This CD11B(hi) F4/80(int) Ly-6C(lo) macrophage subset was most abundant in livers during maximal fibrosis resolution and represented the principle matrix metalloproteinase (MMP) -expressing subset. Depletion of this population in CD11B promoter-diphtheria toxin receptor (CD11B-DTR) transgenic mice caused a failure of scar remodeling. Adoptive transfer and in situ labeling experiments showed that these restorative macrophages derive from recruited Ly-6C(hi) monocytes, a common origin with profibrotic Ly-6C(hi) macrophages, indicative of a phenotypic switch in vivo conferring proresolution properties. Microarray profiling of the Ly-6C(lo) subset, compared with Ly-6C(hi) macrophages, showed a phenotype outside the M1/M2 classification, with increased expression of MMPs, growth factors, and phagocytosis-related genes, including Mmp9, Mmp12, insulin-like growth factor 1 (Igf1), and Glycoprotein (transmembrane) nmb (Gpnmb). Confocal microscopy confirmed the postphagocytic nature of restorative macrophages. Furthermore, the restorative macrophage phenotype was recapitulated in vitro by the phagocytosis of cellular debris with associated activation of the ERK signaling cascade. Critically, induced phagocytic behavior in vivo, through administration of liposomes, increased restorative macrophage number and accelerated fibrosis resolution, offering a therapeutic strategy to this orphan pathological process.


Assuntos
Antígenos Ly/imunologia , Intoxicação por Tetracloreto de Carbono/imunologia , Regulação da Expressão Gênica/imunologia , Cirrose Hepática/imunologia , Macrófagos/imunologia , Monócitos/imunologia , Animais , Antígenos Ly/genética , Antígeno CD11b/genética , Antígeno CD11b/imunologia , Tetracloreto de Carbono/toxicidade , Intoxicação por Tetracloreto de Carbono/genética , Intoxicação por Tetracloreto de Carbono/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/imunologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/genética , Cirrose Hepática/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , Sistema de Sinalização das MAP Quinases/imunologia , Macrófagos/patologia , Metaloproteinase 12 da Matriz/genética , Metaloproteinase 12 da Matriz/imunologia , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/imunologia , Camundongos , Camundongos Transgênicos , Monócitos/patologia
19.
J Hepatol ; 60(2): 384-91, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24512822

RESUMO

BACKGROUND & AIMS: It is difficult to determine the different stages of non-alcoholic fatty liver disease without the use of invasive liver biopsy. In this study we investigated five non-invasive biomarkers used previously to detect hepatic fibrosis and determined the level of agreement between them in order to inform future research. METHODS: In the Edinburgh Type 2 Diabetes Study, a population-based cohort aged 60-74 years with type 2 diabetes, 831 participants underwent ultrasound assessment for fatty liver and had serum aspartate aminotransferase to alanine aminotransferase ratio (AST/ALT), aspartate to platelet ratio index (APRI), European Liver Fibrosis panel (ELF), Fibrosis-4 Score (FIB4) and liver stiffness measurement (LSM) measured. RESULTS: Literature based cut-offs yielded marked differences in the proportions of the cohort with probable liver fibrosis in the full cohort. Agreement between the top 5% of the distribution for each biomarker pair was poor. APRI and FIB4 had the best positive agreement at 76.4%, but agreement for all of the other serum biomarker pairs was between 18% and 34%. Agreement with LSM was poor (9-16%). CONCLUSIONS: We found poor correlation between the five biomarkers of liver fibrosis studied. Using the top 5% of each biomarker resulted in good agreement on the absence of advanced liver disease but poor agreement on the presence of advanced disease. Further work is required to validate these markers against liver biopsy and to determine their predictive value for clinical liver-related endpoints, in a range of different low and high risk population groups.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico por imagem , Idoso , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Técnicas de Imagem por Elasticidade , Fígado Gorduroso/sangue , Fígado Gorduroso/complicações , Fígado Gorduroso/diagnóstico por imagem , Feminino , Humanos , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica , Contagem de Plaquetas , Valor Preditivo dos Testes , Escócia
20.
Liver Int ; 34(8): 1267-77, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24237940

RESUMO

BACKGROUND & AIMS: Type 2 diabetes is an established risk factor for the presence and progression of fatty liver. Little is known about the distributions and correlates of hepatic non-invasive biomarkers in community-based populations with diabetes, unselected for liver disease. We aimed to identify the distribution of, and metabolic risk factors associated with serum cytokeratin-18 (CK18) and the Enhanced Liver Fibrosis score (ELF), in a large, representative cohort of people with type 2 diabetes (the Edinburgh Type 2 Diabetes Study, ET2DS). METHODS: Nine hundred and thirty-nine ET2DS participants, aged 60-74 years underwent physical examination including ultrasound for assessment of liver fat. Representative subgroups were assessed for markers of chronic liver disease (CK18 and ELF). RESULTS: CK18 values ranged from 29-993 U/L (median 102, IQR 76-137 U/L) and ELF scores ranged from 6.9-11.6 (mean 8.9, SD 0.8). Statistically significant associations were found between both biomarkers and a number of metabolic risk factors. Neither CK18 nor ELF was consistently or strongly associated with established hepatic risk factors (alcohol excess, hepatotoxic medication use and positive immunology titres). CONCLUSIONS: We identified the distribution of CK18 and ELF in a large cohort of older people with type 2 diabetes and showed that these markers are associated with an adverse metabolic risk factor profile, although much of the variation in biomarkers remained unexplained. Prospective studies are required to determine the extent to which CK18 and/or ELF predict the development of symptomatic liver disease and to identify additional risk factors which may influence the development of advanced liver disease in people with type 2 diabetes.


Assuntos
Biomarcadores/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Fígado Gorduroso/diagnóstico , Fígado Gorduroso/epidemiologia , Idoso , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Fígado Gorduroso/sangue , Fígado Gorduroso/etiologia , Humanos , Queratina-18/sangue , Cirrose Hepática/patologia , Pessoa de Meia-Idade , Fatores de Risco , Escócia/epidemiologia
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