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1.
Am J Pathol ; 194(1): 52-70, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37820926

RESUMEN

Loss of hepatocyte nuclear factor 4α (HNF4α) expression is frequently observed in end-stage liver disease and associated with loss of vital liver functions, thus increasing mortality. Loss of HNF4α expression is mediated by inflammatory cytokines, such as transforming growth factor (TGF)-ß. However, details of how HNF4α is suppressed are largely unknown to date. Herein, TGF-ß did not directly inhibit HNF4α but contributed to its transcriptional regulation by SMAD2/3 recruiting acetyltransferase CREB-binding protein/p300 to the HNF4α promoter. The recruitment of CREB-binding protein/p300 is indispensable for CCAAT/enhancer-binding protein α (C/EBPα) binding, another essential requirement for constitutive HNF4α expression in hepatocytes. Consistent with the in vitro observation, 67 of 98 patients with hepatic HNF4α expressed both phospho-SMAD2 and C/EBPα, whereas 22 patients without HNF4α expression lacked either phospho-SMAD2 or C/EBPα. In contrast to the observed induction of HNF4α, SMAD2/3 inhibited C/EBPα transcription. Long-term TGF-ß incubation resulted in C/EBPα depletion, which abrogated HNF4α expression. Intriguingly, SMAD2/3 inhibitory binding to the C/EBPα promoter was abolished by insulin. Two-thirds of patients without C/EBPα lacked membrane glucose transporter type 2 expression in hepatocytes, indicating insulin resistance. Taken together, these data indicate that hepatic insulin sensitivity is essential for hepatic HNF4α expression in the condition of inflammation.


Asunto(s)
Proteína de Unión a CREB , Insulina , Humanos , Proteína alfa Potenciadora de Unión a CCAAT/metabolismo , Proteína de Unión a CREB/metabolismo , Factor Nuclear 4 del Hepatocito/genética , Factor Nuclear 4 del Hepatocito/metabolismo , Hepatocitos/metabolismo , Hígado/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Factor de Crecimiento Transformador beta/metabolismo
2.
Hepatology ; 75(2): 322-337, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34435364

RESUMEN

BACKGROUND AND AIMS: In patients with acute liver failure (ALF) who suffer from massive hepatocyte loss, liver progenitor cells (LPCs) take over key hepatocyte functions, which ultimately determines survival. This study investigated how the expression of hepatocyte nuclear factor 4α (HNF4α), its regulators, and targets in LPCs determines clinical outcome of patients with ALF. APPROACH AND RESULTS: Clinicopathological associations were scrutinized in 19 patients with ALF (9 recovered and 10 receiving liver transplantation). Regulatory mechanisms between follistatin, activin, HNF4α, and coagulation factor expression in LPC were investigated in vitro and in metronidazole-treated zebrafish. A prospective clinical study followed up 186 patients with cirrhosis for 80 months to observe the relevance of follistatin levels in prevalence and mortality of acute-on-chronic liver failure. Recovered patients with ALF robustly express HNF4α in either LPCs or remaining hepatocytes. As in hepatocytes, HNF4α controls the expression of coagulation factors by binding to their promoters in LPC. HNF4α expression in LPCs requires the forkhead box protein H1-Sma and Mad homolog 2/3/4 transcription factor complex, which is promoted by the TGF-ß superfamily member activin. Activin signaling in LPCs is negatively regulated by follistatin, a hepatocyte-derived hormone controlled by insulin and glucagon. In contrast to patients requiring liver transplantation, recovered patients demonstrate a normal activin/follistatin ratio, robust abundance of the activin effectors phosphorylated Sma and Mad homolog 2 and HNF4α in LPCs, leading to significantly improved coagulation function. A follow-up study indicated that serum follistatin levels could predict the incidence and mortality of acute-on-chronic liver failure. CONCLUSIONS: These results highlight a crucial role of the follistatin-controlled activin-HNF4α-coagulation axis in determining the clinical outcome of massive hepatocyte loss-induced ALF. The effects of insulin and glucagon on follistatin suggest a key role of the systemic metabolic state in ALF.


Asunto(s)
Activinas/genética , Folistatina/metabolismo , Factor Nuclear 4 del Hepatocito/metabolismo , Fallo Hepático Agudo/metabolismo , Activinas/metabolismo , Insuficiencia Hepática Crónica Agudizada/sangre , Adulto , Anciano , Animales , Coagulación Sanguínea , Línea Celular , Factor V/genética , Femenino , Folistatina/sangre , Estudios de Seguimiento , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Expresión Génica , Factor Nuclear 4 del Hepatocito/genética , Hepatocitos/metabolismo , Humanos , Fallo Hepático Agudo/inducido químicamente , Fallo Hepático Agudo/patología , Fallo Hepático Agudo/cirugía , Regeneración Hepática , Trasplante de Hígado , Masculino , Metronidazol , Ratones , Persona de Mediana Edad , Pronóstico , Regiones Promotoras Genéticas , Estudios Prospectivos , Protrombina/genética , Transducción de Señal , Proteína Smad2/genética , Proteína Smad2/metabolismo , Proteína smad3/genética , Proteína smad3/metabolismo , Proteína Smad4/genética , Células Madre/metabolismo , Factor de Crecimiento Transformador beta1/genética , Pez Cebra
3.
Gastroenterology ; 156(1): 187-202.e14, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30267710

RESUMEN

BACKGROUND & AIMS: Upon liver injury in which hepatocyte proliferation is compromised, liver progenitor cells (LPCs), derived from biliary epithelial cells (BECs), differentiate into hepatocytes. Little is known about the mechanisms of LPC differentiation. We used zebrafish and mouse models of liver injury to study the mechanisms. METHODS: We used transgenic zebrafish, Tg(fabp10a:CFP-NTR), to study the effects of compounds that alter epigenetic factors on BEC-mediated liver regeneration. We analyzed zebrafish with disruptions of the histone deacetylase 1 gene (hdac1) or exposed to MS-275 (an inhibitor of Hdac1, Hdac2, and Hdac3). We also analyzed zebrafish with mutations in sox9b, fbxw7, kdm1a, and notch3. Zebrafish larvae were collected and analyzed by whole-mount immunostaining and in situ hybridization; their liver tissues were collected for quantitative reverse transcription polymerase chain reaction. We studied mice in which hepatocyte-specific deletion of ß-catenin (Ctnnb1flox/flox mice injected with Adeno-associated virus serotype 8 [AAV8]-TBG-Cre) induces differentiation of LPCs into hepatocytes after a choline-deficient, ethionine-supplemented (CDE) diet. Liver tissues were collected and analyzed by immunohistochemistry and immunoblots. We performed immunohistochemical analyses of liver tissues from patients with compensated or decompensated cirrhosis or acute on chronic liver failure (n = 15). RESULTS: Loss of Hdac1 activity in zebrafish blocked differentiation of LPCs into hepatocytes by increasing levels of sox9b mRNA and reduced differentiation of LPCs into BECs by increasing levels of cdk8 mRNA, which encodes a negative regulator gene of Notch signaling. We identified Notch3 as the receptor that regulates differentiation of LPCs into BECs. Loss of activity of Kdm1a, a lysine demethylase that forms repressive complexes with Hdac1, produced the same defects in differentiation of LPCs into hepatocytes and BECs as observed in zebrafish with loss of Hdac1 activity. Administration of MS-275 to mice with hepatocyte-specific loss of ß-catenin impaired differentiation of LPCs into hepatocytes after the CDE diet. HDAC1 was expressed in reactive ducts and hepatocyte buds of liver tissues from patients with cirrhosis. CONCLUSIONS: Hdac1 regulates differentiation of LPCs into hepatocytes via Sox9b and differentiation of LPCs into BECs via Cdk8, Fbxw7, and Notch3 in zebrafish with severe hepatocyte loss. HDAC1 activity was also required for differentiation of LPCs into hepatocytes in mice with liver injury after the CDE diet. These pathways might be manipulated to induce LPC differentiation for treatment of patients with advanced liver diseases.


Asunto(s)
Conductos Biliares/enzimología , Diferenciación Celular , Proliferación Celular , Quinasa 8 Dependiente de Ciclina/metabolismo , Hepatocitos/enzimología , Histona Desacetilasa 1/metabolismo , Regeneración Hepática , Hígado/enzimología , Factor de Transcripción SOX9/metabolismo , Células Madre/enzimología , Proteínas de Pez Cebra/metabolismo , Insuficiencia Hepática Crónica Agudizada/enzimología , Insuficiencia Hepática Crónica Agudizada/patología , Animales , Conductos Biliares/patología , Deficiencia de Colina/genética , Deficiencia de Colina/metabolismo , Deficiencia de Colina/patología , Quinasa 8 Dependiente de Ciclina/genética , Modelos Animales de Enfermedad , Proteína 7 que Contiene Repeticiones F-Box-WD/genética , Proteína 7 que Contiene Repeticiones F-Box-WD/metabolismo , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Hepatocitos/patología , Histona Desacetilasa 1/genética , Humanos , Hígado/patología , Cirrosis Hepática/enzimología , Cirrosis Hepática/patología , Ratones Noqueados , Mutación , Receptor Notch3/genética , Receptor Notch3/metabolismo , Factor de Transcripción SOX9/genética , Transducción de Señal , Células Madre/patología , Pez Cebra/genética , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética , beta Catenina/genética , beta Catenina/metabolismo
4.
Br J Cancer ; 119(11): 1358-1366, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30420613

RESUMEN

BACKGROUND: Sex-determining region Y-box (SRY-box) containing gene 9 (SOX9) expression confers cancer stem cell features. However, SOX9 function in intrahepatic cholangiocarcinoma (iCCA) is unknown. This study investigated the effects and underlying mechanisms of SOX9 in iCCA. METHODS: SOX9 expression in 59 iCCA patients was examined by immunohistochemistry. The association between SOX9 expression and clinical outcome was evaluated. Gene signature and biological functions of SOX9 in iCCA were examined in vitro. RESULTS: iCCA patients with high SOX9 expression had shorter survival time than those with low SOX9. In patients receiving chemotherapy, median survival time in patients with low and high levels of SOX9 were 62 and 22 months, respectively. In vitro, gemcitabine increased SOX9 expression in iCCA cells. When SOX9 was knocked down, gemcitabine-induced apoptosis was markedly increased. Silencing SOX9 significantly inhibited gemcitabine-induced phosphorylation of checkpoint kinase 1, a key cell cycle checkpoint protein that coordinates the DNA damage response and inhibited the expression of multidrug resistance genes. Microarray analyses showed that SOX9 knockdown in CCA cells altered gene signatures associated with multidrug resistance and p53 signalling. CONCLUSIONS: SOX9 governs the response of CCA cells to chemotherapy. SOX9 is a biomarker to select iCCA patients eligible for efficient chemotherapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias de los Conductos Biliares/tratamiento farmacológico , Colangiocarcinoma/tratamiento farmacológico , Resistencia a Antineoplásicos/genética , Factor de Transcripción SOX9/metabolismo , Biomarcadores de Tumor/metabolismo , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Enfermedad Crónica , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapéutico , Humanos , Hepatopatías/metabolismo , Factor de Transcripción SOX9/genética , Análisis de Supervivencia , Resultado del Tratamiento , Gemcitabina
5.
Am J Pathol ; 186(7): 1874-1889, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27171900

RESUMEN

Disrupting Notch signaling ameliorates experimental liver fibrosis. However, the role of individual Notch ligands in liver damage is unknown. We investigated the effects of Delta-like ligand 4 (Dll4) in liver disease. DLL4 expression was measured in 31 human liver tissues by immunohistochemistry. Dll4 function was examined in carbon tetrachloride- and bile duct ligation-challenged mouse models in vivo and evaluated in hepatic stellate cells, hepatocytes, and Kupffer cells in vitro. DLL4 was expressed in patients' Kupffer and liver sinusoidal endothelial cells. Recombinant Dll4 protein (rDll4) ameliorated hepatocyte apoptosis, inflammation, and fibrosis in mice after carbon tetrachloride challenge. In vitro, rDll4 significantly decreased lipopolysaccharide-dependent chemokine expression in both Kupffer and hepatic stellate cells. In bile duct ligation mice, rDll4 induced massive hepatic necrosis, resulting in the death of all animals within 1 week. Inflammatory cell infiltration and chemokine ligand 2 (Ccl2) expression were significantly reduced in rDll4-receiving bile duct ligation mice. Recombinant Ccl2 rescued bile duct ligation mice from rDll4-mediated death. In patients with acute-on-chronic liver failure, DLL4 expression was inversely associated with CCL2 abundance. Mechanistically, Dll4 regulated Ccl2 expression via NF-κB. Taken together, Dll4 modulates liver inflammatory response by down-regulating chemokine expression. rDll4 application results in opposing outcomes in two models of liver damage. Loss of DLL4 may be associated with CCL2-mediated cytokine storm in patients with acute-on-chronic liver failure.


Asunto(s)
Quimiocinas/biosíntesis , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Hepatopatías/patología , Proteínas de la Membrana/metabolismo , Animales , Western Blotting , Quimiocina CCL2/biosíntesis , Regulación hacia Abajo , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunohistoquímica , Hepatopatías/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Reacción en Cadena en Tiempo Real de la Polimerasa
6.
J Hepatol ; 63(1): 50-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25646889

RESUMEN

BACKGROUND & AIMS: Distinguishing between acute on chronic liver failure (ACLF) and decompensated liver cirrhosis is difficult due to a lack of pathological evidence. METHODS: A prospective single-center study investigated 174 patients undergoing liver transplantation due to acute decompensation of hepatitis B virus (HBV)-associated liver cirrhosis. Two groups were distinguished by the presence or absence of submassive hepatic necrosis (SMHN, defined as necrosis of 15-90% of the entire liver on explant). Core clinical features of ACLF were compared between these groups. Disease severity scoring systems were applied to describe liver function and organ failure. Serum cytokine profile assays, gene expression microarrays and immunohistochemical analyzes were used to study systemic and local inflammatory responses. RESULTS: SMHN was identified in 69 of 174 patients proven to have cirrhosis by histological means. Characteristic features of SMHN were extensive necrosis along terminal hepatic veins and spanning multiple adjacent cirrhotic nodules accompanied by various degrees of liver progenitor cell-derived regeneration, cholestasis, and ductular bilirubinostasis. Patients with SMHN presented with more severely impaired hepatic function, a higher prevalence of multiple organ failure (as indicated by higher CLIF-SOFA and SOFA scores) and a shorter interval between acute decompensation and liver transplantation than those without SMHN (p<0.01 for all parameters). Further analyzes based on serum cytokine profile assays, gene expression microarrays and immunohistochemical analyzes revealed higher levels of anti-inflammatory cytokines in patients with SMHN. CONCLUSIONS: SMHN is a critical histological feature of HBV-associated ACLF. Identification of a characteristic pathological feature strongly supports that ACLF is a separate entity in end-stage liver disease.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada/diagnóstico , Cirrosis Hepática/diagnóstico , Hígado/patología , Insuficiencia Hepática Crónica Agudizada/cirugía , Diagnóstico Diferencial , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Anticuerpos contra la Hepatitis B/inmunología , Virus de la Hepatitis B/inmunología , Humanos , Trasplante de Hígado , Masculino , Persona de Mediana Edad , Necrosis/diagnóstico , Pronóstico , Estudios Prospectivos , Índice de Severidad de la Enfermedad
7.
Clin Sci (Lond) ; 128(11): 761-74, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25602745

RESUMEN

Transforming growth factor ß (TGF-ß) is cytostatic towards damage-induced compensatory hepatocyte proliferation. This function is frequently lost during hepatocarcinogenesis, thereby switching the TGF-ß role from tumour suppressor to tumour promoter. In the present study, we investigate Smad7 overexpression as a pathophysiological mechanism for cytostatic TGF-ß inhibition in liver damage and hepatocellular carcinoma (HCC). Transgenic hepatocyte-specific Smad7 overexpression in damaged liver of fumarylacetoacetate hydrolase (FAH)-deficient mice increased compensatory proliferation of hepatocytes. Similarly, modulation of Smad7 expression changed the sensitivity of Huh7, FLC-4, HLE and HLF HCC cell lines for cytostatic TGF-ß effects. In our cohort of 140 HCC patients, Smad7 transcripts were elevated in 41.4% of HCC samples as compared with adjacent tissue, with significant positive correlation to tumour size, whereas low Smad7 expression levels were significantly associated with worse clinical outcome. Univariate and multivariate analyses indicate Smad7 levels as an independent predictor for overall (P<0.001) and disease-free survival (P=0.0123). Delineating a mechanism for Smad7 transcriptional regulation in HCC, we identified cold-shock Y-box protein-1 (YB-1), a multifunctional transcription factor. YB-1 RNAi reduced TGF-ß-induced and endogenous Smad7 expression in Huh7 and FLC-4 cells respectively. YB-1 and Smad7 mRNA expression levels correlated positively (P<0.0001). Furthermore, nuclear co-localization of Smad7 and YB-1 proteins was present in cancer cells of those patients. In summary, the present study provides a YB-1/Smad7-mediated mechanism that interferes with anti-proliferative/tumour-suppressive TGF-ß actions in a subgroup of HCC cells that may facilitate aspects of tumour progression.


Asunto(s)
Carcinoma Hepatocelular/genética , Proliferación Celular , Hepatocitos/metabolismo , Hepatopatías/genética , Neoplasias Hepáticas/genética , Proteína smad7/genética , Animales , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Células Cultivadas , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células Hep G2 , Humanos , Hepatopatías/metabolismo , Hepatopatías/patología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Masculino , Ratones de la Cepa 129 , Ratones Noqueados , Ratones Transgénicos , Microscopía Confocal , Persona de Mediana Edad , Análisis Multivariante , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteína smad7/metabolismo , Análisis de Supervivencia , Factor de Crecimiento Transformador beta/farmacología , Proteína 1 de Unión a la Caja Y/genética , Proteína 1 de Unión a la Caja Y/metabolismo
8.
Hepatol Commun ; 8(8)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39023343

RESUMEN

BACKGROUND: When massive necrosis occurs in acute liver failure (ALF), rapid expansion of HSCs called liver progenitor cells (LPCs) in a process called ductular reaction is required for survival. The underlying mechanisms governing this process are not entirely known to date. In ALF, high levels of retinoic acid (RA), a molecule known for its pleiotropic roles in embryonic development, are secreted by activated HSCs. We hypothesized that RA plays a key role in ductular reaction during ALF. METHODS: RNAseq was performed to identify molecular signaling pathways affected by all-trans retinoid acid (atRA) treatment in HepaRG LPCs. Functional assays were performed in HepaRG cells treated with atRA or cocultured with LX-2 cells and in the liver tissue of patients suffering from ALF. RESULTS: Under ALF conditions, activated HSCs secreted RA, inducing RARα nuclear translocation in LPCs. RNAseq data and investigations in HepaRG cells revealed that atRA treatment activated the WNT-ß-Catenin pathway, enhanced stemness genes (SOX9, AFP, and others), increased energy storage, and elevated the expression of ATP-binding cassette transporters in a RARα nuclear translocation-dependent manner. Further, atRA treatment-induced pathways were confirmed in a coculture system of HepaRG with LX-2 cells. Patients suffering from ALF who displayed RARα nuclear translocation in the LPCs had significantly better MELD scores than those without. CONCLUSIONS: During ALF, RA secreted by activated HSCs promotes LPC activation, a prerequisite for subsequent LPC-mediated liver regeneration.


Asunto(s)
Fallo Hepático Agudo , Células Madre , Tretinoina , Humanos , Tretinoina/farmacología , Células Madre/efectos de los fármacos , Vía de Señalización Wnt/efectos de los fármacos , Hígado/efectos de los fármacos , Receptor alfa de Ácido Retinoico/genética , Receptor alfa de Ácido Retinoico/metabolismo , Técnicas de Cocultivo , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo
9.
J Hepatol ; 59(4): 738-45, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23747755

RESUMEN

BACKGROUND & AIMS: Proliferation of liver progenitor cells (LPCs) is associated with inflammation and fibrosis in chronic liver diseases. However, how inflammation and fibrosis affect LPCs remains obscure. METHODS: We examined the role of interferon (IFN)-γ, an important pro-inflammatory and anti-fibrotic cytokine, in LPC expansion in HBV-infected patients and in mice challenged with 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)- or choline-deficient, ethionine-supplemented (CDE) diet as well as in primary LPCs and LPC cell line. RESULTS: The CK19 staining scores correlated with inflammation and fibrosis grades in the livers from 110 HBV-infected patients. Nine-month IFN-γ treatment decreased LPC numbers, inflammation, and fibrosis in these HBV-infected patients. Similarly, a two-week IFN-γ treatment also decreased LPC activation in DDC-treated mice. Disruption of IFN-γ or its signaling components (e.g., IFNGR, STAT1, and IRF-1) increased LPC proliferation and liver fibrosis in DDC-fed mice. In contrast, deletion of IFN-γ did not increase, but rather slightly reduced LPC proliferation in CDE-fed mice. In vitro, IFN-γ attenuated proliferation of the LPC cell line BMOL and of primary LPCs from wild type mice, but not STAT1(-/-) or IRF-1(-/-) mice. Furthermore, co-culture assays suggest that IFN-γ can indirectly promote LPC proliferation via the activation of macrophages but attenuate it via the inhibition of hepatic stellate cells. CONCLUSIONS: IFN-γ inhibits LPC expansion via the direct inhibition of LPC proliferation and indirect attenuation of liver fibrosis in the DDC model, but it may also enhance LPC expansion via the promotion of inflammation in the CDE model; thereby playing dual roles in regulating LPC proliferation in vivo.


Asunto(s)
Células Madre Adultas/citología , Hepatitis B Crónica/patología , Hepatocitos/citología , Interferón gamma/fisiología , Células Madre Adultas/efectos de los fármacos , Células Madre Adultas/fisiología , Animales , Línea Celular , Proliferación Celular/efectos de los fármacos , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/patología , Células Estrelladas Hepáticas/fisiología , Hepatitis B Crónica/fisiopatología , Hepatocitos/efectos de los fármacos , Hepatocitos/fisiología , Humanos , Interferón gamma/deficiencia , Interferón gamma/farmacología , Cirrosis Hepática/patología , Cirrosis Hepática/fisiopatología , Cirrosis Hepática/prevención & control , Activación de Macrófagos/efectos de los fármacos , Ratones , Ratones Noqueados , Piridinas/administración & dosificación , Piridinas/toxicidad , Transducción de Señal/efectos de los fármacos
10.
J Transl Med ; 11: 234, 2013 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-24289155

RESUMEN

BACKGROUND AND AIM: Due to known limitations of liver biopsy, reliable non-invasive serum biomarkers for chronic liver diseases are needed. We performed serum peptidomics for such investigation in compensated chronic hepatitis B (CHB) patients. METHODS: Liquid chromatography combined with tandem mass spectrometry (LC-MS/MS) was used to identify differentially expressed peptides in sera from 40 CHB patients (20 with S0G0-S1G1 and 20 with S3G3-S4G4). Ion pair quantification from differentially expressed peptides in a validation set of sera from 86 CHB patients was done with multiple reaction monitoring (MRM). RESULTS: 21 differentially represented peptide peaks were found through LC-MS/MS. Ion pairs generated from eleven of these peptides (m/z < 800) were quantified by MRM. Summed peak area ratios of 6 ion pairs from peptide m/z 520.3 (176.1, 353.7, 459.8, 503.3, 351.3, 593.1), which was identified as dihydroxyacetone kinase (DAK) fragment, decreased from mild to advanced stages of fibrosis or inflammation. Area Under Receiver Operating Characteristic Curves (AUROCs) of five ion models discriminating fibrosis degrees were 0.871 ~ 0.915 (S2-4 versus S0-1) and 0.804 ~ 0.924 (S3-4 versus S0-2). AUROCs discriminating inflammation grades were 0.840 ~ 0.902 (G2-4 versus G0-1) and 0.787 ~ 0.888 (G3-4 versus G0-2). The diagnostic power of these models provides improved sensitivity and specificity for predicting disease progression as compared to aspartate aminotransferase to platelet ratio index (APRI), FIB-4, Forn's index and serum DAK protein. CONCLUSIONS: The peptide fragment (m/z 520.3) of DAK is a promising biomarker to guide timing of antiviral treatment and to avoid liver biopsy in compensated CHB patients.


Asunto(s)
Hepatitis B Crónica/sangre , Hepatitis B Crónica/patología , Péptidos/sangre , Fosfotransferasas (Aceptor de Grupo Alcohol)/sangre , Índice de Severidad de la Enfermedad , Secuencia de Aminoácidos , Área Bajo la Curva , Cromatografía Liquida , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/enzimología , Humanos , Iones , Datos de Secuencia Molecular , Péptidos/química , Fosfotransferasas (Aceptor de Grupo Alcohol)/química , Curva ROC , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem
11.
J Immunol ; 187(5): 2814-23, 2011 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-21804025

RESUMEN

Connective tissue growth factor (CTGF) plays a central role in stimulating extracellular matrix deposition in the liver, and hence is considered a critical mediator of TGF-ß-dependent fibrogenesis. Hepatic stellate cells (HSCs) are known as the major source of CTGF in damaged liver. However, previous studies revealed that IL-13, rather than TGF-ß, represents the predominant inducer of CTGF expression in HSCs. We now dissected IL-13 downstream signaling that modulates CTGF expression in HSCs. IL-13 induces a time- and dosage-dependent increase of CTGF in a TGF-ß-independent manner. This process requires participation of different Smad proteins and their upstream receptor kinases (activin receptor-like kinases). Smad1 and Smad2 were identified as the key mediators of IL-13-dependent CTGF expression. Furthermore, IL-13 induces Stat6 phosphorylation in HSCs, but Stat6 was not involved in CTGF induction. Instead, the Erk1/2-MAPK pathway was found to be responsible for IL-13-induced early Smad phosphorylation and CTGF synthesis. We demonstrate that IL-13 induces CTGF expression in HSCs by activating TGF-ß-independent activin receptor-like kinase/Smad signaling via the Erk-MAPK pathway rather than via its canonical JAK/Stat6 pathway. These results provide an improved new insight into the molecular mechanisms of profibrotic IL-13 activities in the liver.


Asunto(s)
Factor de Crecimiento del Tejido Conjuntivo/biosíntesis , Células Estrelladas Hepáticas/metabolismo , Interleucina-13/metabolismo , Cirrosis Hepática/metabolismo , Proteína Smad1/metabolismo , Proteína Smad2/metabolismo , Animales , Western Blotting , Regulación de la Expresión Génica/fisiología , Técnicas de Silenciamiento del Gen , Humanos , ARN Interferente Pequeño , Ratas , Ratas Wistar , Transducción de Señal , Factor de Crecimiento Transformador beta/metabolismo
12.
Biomolecules ; 12(1)2022 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-35053214

RESUMEN

Massive hepatic necrosis is the most severe lesion in acute liver failure, yet a portion of patients manage to survive and recover from this high-risk and harsh disease syndrome. The mechanisms underlying recovery remain largely unknown to date. Recent research progress highlights a key role of liver progenitor cells, the smallest biliary cells, in the maintenance of liver homeostasis and thus survival. These stem-like cells rapidly proliferate and take over crucial hepatocyte functions in a severely damaged liver. Hence, the new findings not only add to our understanding of the huge regenerative capability of the liver, but also provide potential new targets for the pharmacological management of acute liver failure in clinical practice.


Asunto(s)
Diferenciación Celular , Hepatocitos/metabolismo , Fallo Hepático Agudo/metabolismo , Regeneración Hepática , Hígado/metabolismo , Células Madre/metabolismo , Animales , Humanos
13.
BMJ Open ; 12(6): e054891, 2022 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-35760549

RESUMEN

OBJECTIVES: To clarify non-alcoholic fatty liver disease (NAFLD) prevalence, risk factors and clinical outcome in an exemplary Chinese population, a cohort of company employees was followed up for 11 years. DESIGN: Retrospective cohort study. SETTING: Between 2006 and 2016 in Ning bo, China. PARTICIPANTS: 13 032 company employees. RESULTS: Over 11 years, the prevalence of NAFLD increased from 17.2% to 32.4% (men 20.5%-37% vs women 9.8%-22.2%). Male peak prevalence was between 40 and 60 years of age, whereas highest prevalence in women was at an age of 60 years and older. Logistic and Cox regression revealed 16 risk factors, including body mass index (BMI), albumin, white blood cell, triglycerides (TG), high-density lipoprotein, glutamyl transpeptidase, alanine transaminase, creatinine, urea acid, glucose, systolic blood pressure, diastolic blood pressure, blood sedimentation, haemoglobin, platelet and apolipoprotein B2 (p<0.05 for all factors). The area under the curve of these variables for NAFLD is 0.88. However, cause-effect analyses showed that only BMI, gender and TG directly contributed to NAFLD development. Over an 11-year follow-up period, 12.6%, 37.7% and 14.2% of male patients with NAFLD and 11.6%, 44.7% and 22.6% of female patients with NAFLD developed diabetes, hypertension and hyperuricaemia, respectively. Except one male patient who developed cirrhosis, no patients with NAFLD progressed into severe liver disease. CONCLUSION: Diabetes, hypertension and hyperuricaemia are the main clinical outcomes of NAFLD. Eleven years of NAFLD are not sufficient to cause severe liver disease. Age and obesity are direct risk factors for NAFLD. BMI, gender and TG are three parameters directly reflecting the occurrence of NAFLD.


Asunto(s)
Diabetes Mellitus , Hipertensión , Hiperuricemia , Enfermedad del Hígado Graso no Alcohólico , Femenino , Estudios de Seguimiento , Humanos , Hipertensión/epidemiología , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Estudios Retrospectivos , Triglicéridos
14.
Hepatobiliary Pancreat Dis Int ; 10(2): 151-7, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21459721

RESUMEN

BACKGROUND: The first priority in treating fibrosis is to eliminate the causes that result in liver injury, e.g., hepatitis B and C virus. However, in many liver diseases the cause is either unknown or untreatable. The present study was designed to investigate the long-term antifibrotic effect of interferon-gamma (IFN-gamma) treatment in patients chronically infected with hepatitis B virus. METHODS: A total of 42 patients, 30 treated with IFN-gamma and 12 controls, were enrolled from an original clinical trial (Clin Gastroenterol Hepatol 2005;3:819.). Three serial liver biopsies that were obtained at the initiation and end of IFN-gamma treatment as well as 4 to 6 years after treatment discontinuation were assessed according to the modified Chevallier scoring system. RESULTS: Twenty-five out of 30 IFN-gamma-treated patients were followed up until 4 to 6 years after the treatment was stopped. However, all controls were excluded from follow-up due to death, loss and elevated virus level within 2 years. Twenty-five IFN-gamma-treated patients had stable serum liver function and liver fibrosis indices without any further anti-viral or anti-fibrotic treatment. Improved inflammatory and fibrotic scores were found after nine months of IFN-gamma treatment according to the modified Chevallier scoring system (inflammation: 11.8+/-6.5 at the beginning of IFN-gamma treatment vs. 9.2+/-4.1 after 9 months, P<0.05; fibrosis: 15.0+/-7.3 at baseline vs. 12.6+/-6.8 after 9 months, P<0.05). Among them, 14 patients accepted a third serial liver biopsy 4 to 6 years after treatment discontinuation, and the fibrotic score was increased (14.2+/-8.3 vs. 11.9+/-7.6 after 9 months, P<0.05). CONCLUSIONS: Nine-month IFN-gamma treatment significantly improves the fibrosis score in patients with chronic HBV infection. The majority of patients demonstrate stable serum biochemical indices and quality of life. However, they do not show a long-term benefit according to histological criteria. Given the limited sample size, long-term IFN-gamma treatment regimens should be assessed in further clinical trials.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis B Crónica/tratamiento farmacológico , Interferón gamma/uso terapéutico , Cirrosis Hepática/tratamiento farmacológico , Adulto , Femenino , Hepatitis B Crónica/patología , Hepatitis B Crónica/fisiopatología , Humanos , Hígado/patología , Cirrosis Hepática/patología , Masculino , Persona de Mediana Edad , Proteínas Recombinantes
15.
World J Clin Cases ; 9(20): 5514-5525, 2021 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-34307604

RESUMEN

BACKGROUND: The impact of type 2 diabetes mellitus (T2DM) on the prognosis and complications of liver cirrhosis is not fully clarified. AIM: To clarify the mortality and related risk factors as well as complications in cirrhotic patients with T2DM. METHODS: We searched PubMed, EMBASE, and the Cochrane Library from their inception to December 1, 2020 for cohort studies comparing liver transplant-free mortality, hepatocellular carcinoma (HCC), ascites, spontaneous bacterial peritonitis (SBP), variceal bleeding, and hepatic encephalopathy (HE) in cirrhotic patients with vs without T2DM. Odds ratios (ORs) were combined by using fixed-effects or random-effects models with RevMan software. RESULTS: The database search generated a total of 17 cohort studies that met the inclusion criteria. Among these studies, eight reported the risk of mortality, and eight reported the risk of HCC. Three studies provided SBP rates, and two documented ascites rates. Four articles focused on HE rates, and three focused on variceal bleeding rates. Meta-analysis indicated that T2DM was significantly associated with an increased risk of liver transplant-free mortality [OR: 1.28, 95% confidence intervals (CI): 1.16-1.41, P < 0.0001] and HCC incidence (OR: 1.82, 95%CI: 1.32-2.51, P = 0.003). The risk of SBP was not significantly increased (OR: 1.16 95%CI: 0.86-1.57, P = 0.34). Additionally, T2DM did not significantly increase HE (OR: 1.31 95%CI: 0.97-1.77, P = 0.08), ascites (OR: 1.11 95%CI: 0.84-1.46, P = 0.46), and variceal bleeding (OR: 1.34, 95%CI: 0.99-1.82, P = 0.06). CONCLUSION: The findings suggest that cirrhotic patients with T2DM have a poor prognosis and high risk of HCC. T2DM may not be associated with an increased risk of SBP, variceal bleeding, ascites, or HE in cirrhotic patients with T2DM.

16.
J Hepatol ; 52(3): 407-16, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20129692

RESUMEN

BACKGROUND & AIMS: Adverse alcohol effects in the liver involve oxidative metabolism, fat deposition and release of fibrogenic mediators, including TGF-beta. The work presents an assessment of liver damaging cross-talk between ethanol and TGF-beta in hepatocytes. METHODS: To investigate TGF-beta effects on hepatocytes, microarray analyses were performed and validated by qRT-PCR, Western blot analysis and immunohistochemistry. The cellular state was determined by assessing lactate dehydrogenase, cellular glutathione, reactive oxygen species, lipid peroxidation and neutral lipid deposition. RNA interference was used for gene silencing in vitro. RESULTS: TGF-beta is induced in mouse livers after chronic ethanol insult, enhances ethanol induced oxidative stress and toxicity towards cultured hepatocytes plus induces lipid-, oxidative stress metabolism- and fibrogenesis-gene expression signatures. Interestingly, TGF-beta down-regulates alcohol metabolizing enzyme Adh1 mRNA in cultured hepatocytes and liver tissue from TGF-beta transgenic mice via the ALK5/Smad2/3 signalling branch, with Smad7 as a potent negative regulator. ADH1 deficiency is a determining factor for the increased lipid accumulation and Cyp2E1 dependent toxicity in liver cells upon alcohol challenge. Further, ADH1 expression was decreased during liver damage in an intragastric ethanol infusion mouse model. CONCLUSION: In the presence of ethanol, TGF-beta displays pro-steatotic action in hepatocytes via decreasing ADH1 expression. Low ADH1 levels are correlated with enhanced hepatocyte damage upon chronic alcohol consumption by favoring secondary metabolic pathways.


Asunto(s)
Alcohol Deshidrogenasa/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Regulación hacia Abajo/fisiología , Etanol/efectos adversos , Hepatocitos/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Animales , Células Cultivadas , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Modelos Animales de Enfermedad , Hepatocitos/patología , Metabolismo de los Lípidos/fisiología , Peroxidación de Lípido/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Estrés Oxidativo/fisiología , Proteínas Serina-Treonina Quinasas/metabolismo , Receptor Tipo I de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Transducción de Señal/fisiología , Proteína smad7/metabolismo
17.
Hepatology ; 50(1): 230-43, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19441105

RESUMEN

UNLABELLED: It is unknown whether transforming growth factor beta1 (TGF-beta1) signaling uniformly participates in fibrogenic chronic liver diseases, irrespective of the underlying origin, or if other cytokines such as interleukin (IL)-13 share in fibrogenesis (e.g., due to regulatory effects on type I pro-collagen expression). TGF-beta1 signaling events were scored in 396 liver tissue samples from patients with diverse chronic liver diseases, including hepatitis B virus (HBV), hepatitis C virus (HCV), Schistosoma japonicum infection, and steatosis/steatohepatitis. Phospho-Smad2 staining correlated significantly with fibrotic stage in patients with HBV infection (n = 112, P < 0.001) and steatosis/steatohepatitis (n = 120, P < 0.01), but not in patients with HCV infection (n = 77, P > 0.05). In tissue with HBx protein expression, phospho-Smad2 was detectable, suggesting a functional link between viral protein expression and TGF-beta1 signaling. For IL-13, immunostaining correlated with fibrotic stage in patients with HCV infection and steatosis/steatohepatitis. IL-13 protein was more abundant in liver tissue lysates from three HCV patients compared with controls, as were IL-13 serum levels in 68 patients with chronic HCV infection compared with 20 healthy volunteers (72.87 +/- 26.38 versus 45.41 +/- 3.73, P < 0.001). Immunohistochemistry results suggest that IL-13-mediated liver fibrogenesis may take place in the absence of phospho-signal transducer and activator of transcription protein 6 signaling. In a subgroup of patients with advanced liver fibrosis (stage > or =3), neither TGF-beta nor IL-13 signaling was detectable. CONCLUSION: Depending on the cause of liver damage, a predominance of TGF-beta or IL-13 signaling is found. TGF-beta1 predominance is detected in HBV-related liver fibrogenesis and IL-13 predominance in chronic HCV infection. In some instances, the underlying fibrogenic mediator remains enigmatic.


Asunto(s)
Interleucina-13/fisiología , Cirrosis Hepática/etiología , Factor de Crecimiento Transformador beta1/fisiología , Humanos , Técnicas In Vitro , Hepatopatías/etiología
18.
World J Gastroenterol ; 26(18): 2247-2267, 2020 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-32476790

RESUMEN

BACKGROUND: Computed tomography (CT), liver stiffness measurement (LSM), and magnetic resonance imaging (MRI) are non-invasive diagnostic methods for esophageal varices (EV) and for the prediction of high-bleeding-risk EV (HREV) in cirrhotic patients. However, the clinical use of these methods is controversial. AIM: To evaluate the accuracy of LSM, CT, and MRI in diagnosing EV and predicting HREV in cirrhotic patients. METHODS: We performed literature searches in multiple databases, including PubMed, Embase, Cochrane, CNKI, and Wanfang databases, for articles that evaluated the accuracy of LSM, CT, and MRI as candidates for the diagnosis of EV and prediction of HREV in cirrhotic patients. Summary sensitivity and specificity, positive likelihood ratio and negative likelihood ratio, diagnostic odds ratio, and the areas under the summary receiver operating characteristic curves were analyzed. The quality of the articles was assessed using the quality assessment of diagnostic accuracy studies-2 tool. Heterogeneity was examined by Q-statistic test and I 2 index, and sources of heterogeneity were explored using meta-regression and subgroup analysis. Publication bias was evaluated using Deek's funnel plot. All statistical analyses were conducted using Stata12.0, MetaDisc1.4, and RevMan5.3. RESULTS: Overall, 18, 17, and 7 relevant articles on the accuracy of LSM, CT, and MRI in evaluating EV and HREV were retrieved. A significant heterogeneity was observed in all analyses (P < 0.05). The areas under the summary receiver operating characteristic curves of LSM, CT, and MRI in diagnosing EV and predicting HREV were 0.86 (95% confidence interval [CI]: 0.83-0.89), 0.91 (95%CI: 0.88-0.93), and 0.86 (95%CI: 0.83-0.89), and 0.85 (95%CI: 0.81-0.88), 0.94 (95%CI: 0.91-0.96), and 0.83 (95%CI: 0.79-0.86), respectively, with sensitivities of 0.84 (95%CI: 0.78-0.89), 0.91 (95%CI: 0.87-0.94), and 0.81 (95%CI: 0.76-0.86), and 0.81 (95%CI: 0.75-0.86), 0.88 (95%CI: 0.82-0.92), and 0.80 (95%CI: 0.72-0.86), and specificities of 0.71 (95%CI: 0.60-0.80), 0.75 (95%CI: 0.68-0.82), and 0.82 (95%CI: 0.70-0.89), and 0.73 (95%CI: 0.66-0.80), 0.87 (95%CI: 0.81-0.92), and 0.72 (95%CI: 0.62-0.80), respectively. The corresponding positive likelihood ratios were 2.91, 3.67, and 4.44, and 3.04, 6.90, and2.83; the negative likelihood ratios were 0.22, 0.12, and 0.23, and 0.26, 0.14, and 0.28; the diagnostic odds ratios were 13.01, 30.98, and 19.58, and 11.93, 49.99, and 10.00. CT scanner is the source of heterogeneity. There was no significant difference in diagnostic threshold effects (P > 0.05) or publication bias (P > 0.05). CONCLUSION: Based on the meta-analysis of observational studies, it is suggested that CT imaging, a non-invasive diagnostic method, is the best choice for the diagnosis of EV and prediction of HREV in cirrhotic patients compared with LSM and MRI.


Asunto(s)
Várices Esofágicas y Gástricas/diagnóstico , Hemorragia Gastrointestinal/epidemiología , Cirrosis Hepática/complicaciones , Hígado/diagnóstico por imagen , Diagnóstico por Imagen de Elasticidad/métodos , Várices Esofágicas y Gástricas/etiología , Hemorragia Gastrointestinal/etiología , Humanos , Hígado/patología , Cirrosis Hepática/patología , Imagen por Resonancia Magnética , Estudios Observacionales como Asunto , Curva ROC , Medición de Riesgo/métodos , Tomografía Computarizada por Rayos X
19.
Sci Rep ; 9(1): 18719, 2019 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-31822697

RESUMEN

Fuzhenghuayu (FZHY) is a compound extracted from natural plants. Its anti-fibrotic effect has been confirmed in experimental and clinical studies. However, precise effects and underlying mechanisms of FZHY in liver angiogenesis largely remain understood. In this study, we investigated the effects of FZHY on sinusoidal capillarization and angiogenesis with mice challenged for Carbon tetrachloride (CCl4) and dimethylnitrosamine (DMN), in vitro human hepatic sinusoidal endothelial cells (HHSEC) and Human Umbilical Vein Endothelial Cell (HUVEC) 3D fibrin gel model. Besides its anti-fibrotic effect, FZHY ameliorated CCl4 and DMN-induced sinusoidal capillarization, angiogenesis and expression of angiogenesis-associated factors, i.e. CD31, VEGF, VEGF receptor II, phosphor-ERK and HIF-1α. Consistent with the findings based on animal models, inhibitory effects of FZHY on capillarization and angiogenesis were further confirmed in HHSEC and the HUVEC 3D fibrin gel model, respectively. These data suggest that FZHY ameliorates not only liver fibrosis but also vessel remodeling in experimental models. Therefore, FZHY might be a potentially useful drug to treat liver cirrhosis in clinical practice.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/metabolismo , Animales , Capilares/efectos de los fármacos , Tetracloruro de Carbono/efectos adversos , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/metabolismo , Células Endoteliales/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Hígado/patología , Masculino , Medicina Tradicional China/métodos , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Neovascularización Patológica/metabolismo , Transducción de Señal
20.
J Dig Dis ; 19(3): 118-126, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29389083

RESUMEN

This review provides a personal view on anti-fibrosis therapy in the liver. The worst clinical consequence of liver fibrosis is the development of liver cirrhosis and portal hypertension. Etiology is a decisive factor which determines patterns of fibrous septa and subsequent vascular remodeling, which is essential for the development of portal hypertension. Removing or controlling the disease-causing agent, i.e. anti-viral treatment for hepatitis, is the essential first step for treating chronic liver diseases and can reverse fibrosis in some settings. However, removing etiology is not always sufficient to prevent fibrosis from progressing towards cirrhosis and portal hypertension. In liver diseases such as severe alcoholic hepatitis and massive parenchymal loss, the formation of vascular anastomoses between portal to central veins based on bridging fibrosis results in cirrhosis and portal hypertension. For these patients, anti-fibrotic treatment is crucial and urgent. Unfortunately, a lack of understanding how fibrosis contributes to vascular remodeling caused by and combined with a lack of suitable experimental models that recapitulate human liver diseases, has hampered the development of successful anti-fibrotic drugs for clinical use to date.


Asunto(s)
Cirrosis Hepática/tratamiento farmacológico , Progresión de la Enfermedad , Humanos , Hipertensión Portal/etiología , Interferón gamma/uso terapéutico , Cirrosis Hepática/etiología , Cirrosis Hepática/fisiopatología , Remodelación Vascular/efectos de los fármacos , Remodelación Vascular/fisiología , Cicatrización de Heridas/efectos de los fármacos , Cicatrización de Heridas/fisiología
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