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1.
Artigo em Chinês | MEDLINE | ID: mdl-33660475

RESUMO

OBJECTIVE: To investigate the effects of persistent Echinococcus multilocularis infections on hepatic fibrosis in mice, so as to provide insights into the understanding of liver fibrogenesis induced by E. multilocularis infections and the treatment of alveolar echinococcosis. METHODS: Hepatic stellate HSC-T6 and LX-2 cells were exposed to the sera (25, 50 and 100 µL) from Meriones unguiculatus infected with E. multilocularis, and E. multilocularis, germinal layer cells (GCs) and protoscoleces (PSCs) for 48 hours, respectively. The cell proliferation was measured using a CCK-8 assay, and the levels of collagen 1 (Col1) and α-smooth muscle actin (α-SMA) were measured in the culture supernatant of HSC-T6 cells using ELISA. In addition, the serum and liver samples were collected 1, 2, 4, 6, 8 months post-infection with E. multilocularis, respectively. The serum Col1 and α-SMA concentrations were measured using enzyme-linked immunosorbent assay (ELISA), and the deposition of collagen fibers was examined in mice livers using Sirius red staining. RESULTS: The sera of E. multilocularis-infected gerbils promoted the proliferation of HSC-T6 and LX-2 cells in vitro, and there were significant differences seen in the proliferative rate of HSC-T6 (FHSC-T6 = 126.50, P < 0.05) and LX-2 cells (FLX-2 = 201.50, P < 0.05) among different serum groups, with the highest proliferative rate of HSC-T6 (573.36% ± 206.34%) and LX-2 cells (940.38% ± 61.65%) found following exposure to 100 µL mouse sera. Exposure to serum from E. multilocularis-infected gerbils resulted in an increase in the Col1 and α-SMA levels in the culture supernatant of HSC-T6 cells, with the greatest Col1 (20.99 ng/mL ± 2.01 ng/mL) and α-SMA levels (305.52 pg/mL ± 16.67 pg/mL) measured following exposure to 100 µL sera. The metacestodes (142.65% ± 9.17% and 189.99% ± 7.75%), GCs (118.55% ± 8.96% and 122.54% ± 0.21%) and PSCs of E. multilocularis (156.34% ± 17.45% and 160.59% ± 31.41%) all promoted the proliferation of HSC-T6 and LX-2 cells in vitro, and there were significant differences in the proliferative rates of HSC-T6 (FHSC-T6 = 11.24, P < 0.05) and LX-2 cells among groups (FLX-2 = 47.72, P < 0.05). Exposure to E. multilocularis resulted in an increase in Col1 and α-SMA levels in the culture supernatant of HSC-T6 cells, and the highest Col1 (4.43 ng/mL ± 2.23 ng/mL) and α-SMA levels (285.20 pg/mL ± 90.67 pg/mL) were detected following treatment with E. multilocularis metacestodes. In addition, a persistent increase was seen in the deposition of collagen fibers in mice livers 1 to 8 months post-infection with E. multilocularis, with the greatest Col1 level (280.26 ng/mL ± 23.04 ng/mL) seen 6 months post-infection and the highest α-SMA level (33.68 ng/mL ± 4.45 ng/mL) detected 8 months post-infection, respectively. CONCLUSIONS: Persistent E. multilocularis infections promote hepatic stellate cell proliferation, induce an increase in mouse serum Col1 and α-SMA levels, and cause elevated deposition of collagen fibers in mice livers. The infective stage of E. multilocularis is a critical period for inducing hepatic fibrosis of alveolar echinococcosis.


Assuntos
Equinococose , Echinococcus multilocularis , Animais , Equinococose/patologia , Células Estreladas do Fígado/patologia , Cirrose Hepática/patologia , Camundongos
2.
Nat Commun ; 12(1): 66, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397952

RESUMO

IL11 is important for fibrosis in non-alcoholic steatohepatitis (NASH) but its role beyond the stroma in liver disease is unclear. Here, we investigate the role of IL11 in hepatocyte lipotoxicity. Hepatocytes highly express IL11RA and secrete IL11 in response to lipid loading. Autocrine IL11 activity causes hepatocyte death through NOX4-derived ROS, activation of ERK, JNK and caspase-3, impaired mitochondrial function and reduced fatty acid oxidation. Paracrine IL11 activity stimulates hepatic stellate cells and causes fibrosis. In mouse models of NASH, hepatocyte-specific deletion of Il11ra1 protects against liver steatosis, fibrosis and inflammation while reducing serum glucose, cholesterol and triglyceride levels and limiting obesity. In mice deleted for Il11ra1, restoration of IL11 cis-signaling in hepatocytes reconstitutes steatosis and inflammation but not fibrosis. We found no evidence for the existence of IL6 or IL11 trans-signaling in hepatocytes or NASH. These data show that IL11 modulates hepatocyte metabolism and suggests a mechanism for NAFLD to NASH transition.


Assuntos
Hepatócitos/metabolismo , Interleucina-11/metabolismo , Lipídeos/toxicidade , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Transdução de Sinais , Adulto , Animais , Comunicação Autócrina/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Comportamento Alimentar , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Humanos , Subunidade alfa de Receptor de Interleucina-11/metabolismo , Interleucina-6/metabolismo , Camundongos Knockout , Modelos Biológicos , Comunicação Parácrina/efeitos dos fármacos , Fenótipo , Transdução de Sinais/efeitos dos fármacos
3.
Cell Death Dis ; 11(12): 1066, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33311456

RESUMO

The excessive accumulation of extracellular matrix (ECM) is a key feature of liver fibrosis and the activated hepatic stellate cells (HSCs) are the major producer of ECM proteins. However, the precise mechanisms and target molecules that are involved in liver fibrosis remain unclear. In this study, we reported that activating transcription factor 3 (ATF3) was over-expressed in mice and human fibrotic livers, in activated HSCs and injured hepatocytes (HCs). Both in vivo and in vitro study have revealed that silencing ATF3 reduced the expression of pro-fibrotic genes and inhibited the activation of HSCs, thus alleviating the extent of liver fibrosis, indicating a potential protective role of ATF3 knockdown. However, ATF3 was not involved in either the apoptosis or proliferation of HCs. In addition, our data illustrated that increased nuclear localization of ATF3 promoted the transcription of fibrogenic genes and lnc-SCARNA10, which functioned as a novel positive regulator of TGF-ß signaling in liver fibrogenesis by recruiting SMAD3 to the promoter of these genes. Interestingly, further study also demonstrated that lnc-SCARNA10 promoted the expression of ATF3 in a TGF-ß/SMAD3-dependent manner, revealing a TGF-ß/ATF3/lnc-SCARNA10 axis that contributed to liver fibrosis by activating HSCs. Taken together, our data provide a molecular mechanism implicating induced ATF3 in liver fibrosis, suggesting that ATF3 may represent a useful target in the development of therapeutic strategies for liver fibrosis.


Assuntos
Fator 3 Ativador da Transcrição/metabolismo , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Fator 3 Ativador da Transcrição/genética , Animais , Tetracloreto de Carbono , Células Cultivadas , Retroalimentação Fisiológica , Regulação da Expressão Gênica , Humanos , Cirrose Hepática/genética , Camundongos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima/genética
4.
Nat Commun ; 11(1): 5807, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-33199780

RESUMO

Chronic nonalcoholic steatohepatitis (NASH) is a metabolic disorder that often leads to liver fibrosis, a condition with limited therapy options. Adiponectin is an adipocytokine that regulates glucose and lipid metabolism via binding to its receptors AdipoR1 and AdipoR2, and AdipoRs signaling is reported to enhance fatty acid oxidation and glucose uptake. Here, we synthesize and report an adiponectin-based agonist JT003, which potently improves insulin resistance in high fat diet induced NASH mice and suppresses hepatic stellate cells (HSCs) activation in CCl4 induced liver fibrosis. Mechanistic studies indicate that JT003 simultaneously stimulates AdipoR1- and AdipoR2- mediated signaling pathways as well as the PI3K-Akt pathway. Moreover, JT003 treatment significantly improves ER-mitochondrial axis function, which contributes to the reduced HSCs activation. Thus, the AdipoR1/AdipoR2 dual agonist improves both NASH and fibrosis in mice models, which provides the pharmacological and biological foundation for developing AdipoRs-based therapeutic agents on liver fibrosis.


Assuntos
Retículo Endoplasmático/metabolismo , Mitocôndrias/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/patologia , Receptores de Adiponectina/agonistas , Adenilato Quinase/metabolismo , Alanina Transaminase/sangue , Animais , Tetracloreto de Carbono , Dieta Hiperlipídica , Modelos Animais de Doenças , Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fibrose , Células Hep G2 , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Humanos , Resistência à Insulina , Cirrose Hepática/sangue , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/sangue , Obesidade/sangue , Obesidade/complicações , Obesidade/tratamento farmacológico , PPAR alfa/metabolismo , Peptídeos/química , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Domínios Proteicos , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Adiponectina/metabolismo , Transdução de Sinais , Ganho de Peso/efeitos dos fármacos
5.
Phytomedicine ; 79: 153321, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32919323

RESUMO

BACKGROUND: In the development of liver fibrosis, activated hepatic stellate cells (HSCs) contribute to the synthesis and deposition of extracellular matrix (ECM) proteins. HSC activation is considered as a central driver of liver fibrosis. Recently, microRNAs (miRNAs) have been reported to act as key regulators in HSC activation. PURPOSE: Pinostilbene hydrate (PSH), a methylated derivative of resveratrol, has demonstrated anti-inflammatory, antioxidant and anti-tumour activities. However, the effects of PSH on HSC activation remain unclear. METHODS: The effects of PSH on HSC activation were examined. Moreover, the roles of WNT inhibitory factor 1 (WIF1) and miR-17-5p in the effects of PSH on HSC activation were examined. RESULTS: PSH induced a significant reduction in HSC proliferation. PSH also effectively inhibited HSC activation, with reduced α-SMA and collagen expression. Notably, it was found that Wnt/ß-catenin signalling was involved in the effects of PSH on HSC activation. PSH resulted in Wnt/ß-catenin signalling inactivation, with a reduction in TCF activity as well as ß-catenin nuclear translocation. Further studies showed that PSH inhibited Wnt/ß-catenin signalling via regulation of WIF1 and miR-17-5p. Reduced HSC activation caused by PSH could be restored by loss of WIF1 or miR-17-5p mimics. Luciferase reporter assays further confirmed that WIF1 was a target of miR-17-5p. CONCLUSION: PSH has a significant protective effect against HSC activation. In addition, we demonstrate that PSH enhances WIF1 expression and inhibits Wnt/ß-catenin signalling via miR-17-5p, contributing to the suppression of HSC activation.


Assuntos
Células Estreladas do Fígado/efeitos dos fármacos , MicroRNAs/metabolismo , Estilbenos/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Actinas/genética , Actinas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Camundongos , beta Catenina/metabolismo
6.
Am J Pathol ; 190(11): 2185-2193, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32919978

RESUMO

Chronic alcohol consumption is linked to the development of alcohol-associated liver disease (ALD). This disease is characterized by a clinical spectrum ranging from steatosis to hepatocellular carcinoma. Several cell types are involved in ALD progression, including hepatic macrophages. Kupffer cells (KCs) are the resident macrophages of the liver involved in the progression of ALD by activating pathways that lead to the production of cytokines and chemokines. In addition, KCs are involved in the production of reactive oxygen species. Reactive oxygen species are linked to the induction of oxidative stress and inflammation in the liver. These events are activated by the bacterial endotoxin, lipopolysaccharide, that is released from the gastrointestinal tract through the portal vein to the liver. Lipopolysaccharide is recognized by receptors on KCs that are responsible for triggering several pathways that activate proinflammatory cytokines involved in alcohol-induced liver injury. In addition, KCs activate hepatic stellate cells that are involved in liver fibrosis. Novel strategies to treat ALD aim at targeting Kupffer cells. These interventions modulate Kupffer cell activation or macrophage polarization. Evidence from mouse models and early clinical studies in patients with ALD injury supports the notion that pathogenic macrophage subsets can be successfully translated into novel treatment options for patients with this disease.


Assuntos
Comunicação Celular , Células Estreladas do Fígado/metabolismo , Macrófagos do Fígado/metabolismo , Hepatopatias Alcoólicas/metabolismo , Fígado/metabolismo , Animais , Quimiocinas/metabolismo , Modelos Animais de Doenças , Células Estreladas do Fígado/patologia , Humanos , Macrófagos do Fígado/patologia , Fígado/patologia , Hepatopatias Alcoólicas/patologia , Camundongos , Espécies Reativas de Oxigênio/metabolismo
7.
Phytomedicine ; 78: 153294, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32771890

RESUMO

BACKGROUND: Hepatic fibrosis is considered integral to the progression of chronic liver diseases, as it leads to the development of cirrhosis and hepatocellular carcinoma. The activation of hepatic stellate cells (HSCs) is the dominant event in hepatic fibrogenesis. The transforming growth factor-ß1 (TGF-ß1) and Yes-associated protein (YAP) pathways play a pivotal role in HSC activation, hepatic fibrosis and cirrhosis progression. Therefore, targeting the TGF-ß/Smad and YAP signaling pathways is a promising strategy for antifibrotic therapy. PURPOSE: The present study investigated the protective effects of Physalin D (PD), a withanolide isolated from Physalis species (Solanaceae), against liver fibrosis and further elucidated the mechanisms involved in vitro and in vivo. STUDY DESIGN/METHODS: We conducted a series of experiments using carbon tetrachloride (CCl4)- and bile duct ligation (BDL)-induced fibrotic mice and cultured LX-2 cells. Serum markers of liver injury, and the morphology, histology and fibrosis of liver tissue were investigated. Western blot assays and quantitative real-time PCR were used to investigate the mechanisms underlying the antifibrotic effects of PD. RESULT: PD decreased TGF-ß1-induced COL1A1 promoter activity. PD inhibited TGF-ß1-induced expression of Collagen I and α-smooth muscle actin (α-SMA) in human hepatic stellate LX-2 cells. PD significantly ameliorated hepatic injury, including transaminase activities, histology, collagen deposition and α-SMA, in CCl4- or BDL-induced mice. Moreover, PD markedly decreased the expression of phosphorylated Smad2/3 in vitro and in vivo. Furthermore, PD significantly decreased YAP protein levels, and YAP knockdown did not further enhance the effects of PD, namely α-SMA inhibition, Collagen I expression and YAP target gene expression in LX-2 cells. CONCLUSION: These results clearly show that PD ameliorated experimental liver fibrosis by inhibiting the TGF-ß/Smad and YAP signaling pathways, indicating that PD has the potential to effectively treat liver fibrosis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Células Estreladas do Fígado/efeitos dos fármacos , Cirrose Hepática/tratamento farmacológico , Secoesteroides/farmacologia , Proteínas Smad/metabolismo , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Actinas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Tetracloreto de Carbono/toxicidade , Células Cultivadas , Colágeno Tipo I/genética , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Humanos , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Camundongos Endogâmicos C57BL , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/genética , Fator de Crescimento Transformador beta/farmacologia , Fator de Crescimento Transformador beta1
8.
Am J Pathol ; 190(11): 2267-2281, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32805235

RESUMO

Liver fibrosis is an increasing health problem worldwide, for which no effective antifibrosis drugs are available. Although the involvement of aerobic glycolysis in hepatic stellate cell (HSC) activation has been reported, the role of pyruvate kinase M2 (PKM2) in liver fibrogenesis still remains unknown. We examined PKM2 expression and location in liver tissues and primary hepatic cells. The in vitro and in vivo effects of a PKM2 antagonist (shikonin) and its allosteric agent (TEPP-46) on liver fibrosis were investigated in HSCs and liver fibrosis mouse model. Chromatin immunoprecipitation sequencing and immunoprecipitation were performed to identify the relevant molecular mechanisms. PKM2 expression was significantly up-regulated in both mouse and human fibrotic livers compared with normal livers, and mainly detected in activated, rather than quiescent, HSCs. PKM2 knockdown markedly inhibited the activation and proliferation of HSCs in vitro. Interestingly, the PKM2 dimer, rather than the tetramer, induced HSC activation. PKM2 tetramerization induced by TEPP-46 effectively inhibited HSC activation, reduced aerobic glycolysis, and decreased MYC and CCND1 expression via regulating histone H3K9 acetylation in activated HSCs. TEPP-46 and shikonin dramatically attenuated liver fibrosis in vivo. Our findings demonstrate a nonmetabolic role of PKM2 in liver fibrosis. PKM2 tetramerization or suppression could prevent HSC activation and protects against liver fibrosis.


Assuntos
Células Estreladas do Fígado/enzimologia , Cirrose Hepática/enzimologia , Multimerização Proteica , Piruvato Quinase/metabolismo , Acetilação , Animais , Ciclina D1/metabolismo , Feminino , Células Estreladas do Fígado/patologia , Histonas/metabolismo , Humanos , Cirrose Hepática/patologia , Masculino , Camundongos , Compostos Orgânicos/farmacologia , Proteínas Proto-Oncogênicas c-myc/metabolismo
9.
Mol Immunol ; 126: 31-39, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32745796

RESUMO

Activated hepatic stellate cells (HSCs) are the major cell type involved in the deposition of extracellular matrix (ECM) during the development of hepatic fibrosis. In this study, we revealed that left-right determination factor 2 (LEFTY2), one of the proteins belonging to the transforming growth factor-ß (TGF-ß) protein superfamily, was remarkedly decreased in human hepatic fibrosis tissues and in a carbon tetrachloride (CCl4)-induced liver fibrosis mouse model. In addition, TGF-ß1 treatment markedly reduced the level of LEFTY2 in HSCs. Importantly, overexpression of LEFTY2 suppressed the activation and proliferation of HSCs. LEFTY2 inhibited the expression of TGF-ß1-induced fibrosis-associated genes (α-SMA and COL1a1) in human (LX-2) and rat (HSC-T6) HSC cell lines in vitro. Mechanistically, we demonstrated, for the first time, the role of LEFTY2 in inhibiting TGF-ß1/Smad3 signaling, suggesting that there is a mutual antagonism between LEFTY2 and TGF-ß1/Smad3 signaling during liver fibrosis. Similarly, we observed that LEFTY2 has a negative effect on its downstream genes, including c-MYC, CDK4, and cyclin D1, in liver fibrosis. Collectively, our data strongly indicated that LEFTY2 plays an important role in controlling the proliferation and activation of HSCs in the progression of liver fibrosis and this could be a potential therapeutic target for its treatment.


Assuntos
Células Estreladas do Fígado/patologia , Fatores de Determinação Direita-Esquerda/metabolismo , Cirrose Hepática/patologia , Fígado/patologia , Idoso , Animais , Tetracloreto de Carbono/toxicidade , Linhagem Celular , Proliferação de Células , Regulação para Baixo , Feminino , Humanos , Fígado/efeitos dos fármacos , Cirrose Hepática/induzido quimicamente , Masculino , Camundongos , Pessoa de Meia-Idade , Ratos , Transdução de Sinais , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
10.
J Pharmacol Sci ; 144(3): 172-182, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32811746

RESUMO

Hepatitis B virus X protein (HBx) and hepatic stellate cells (HSCs) are critical for liver fibrosis development. Anti-fibrosis occurs via reversion to quiescent-type HSCs or clearance of HSCs via apoptosis or ferroptosis. We aimed to elucidate the role of chrysophanol in rat HSC-T6 cells expressing HBx and investigate whether chrysophanol (isolated from Rheum palmatum rhizomes) influences cell death via ferroptosis in vitro. Analysis of lipid reactive oxygen species (ROS), Bip, CHOP, p-IRE1α, GPX4, SLC7A11, α-SMA, and CTGF showed that chrysophanol attenuated HBx-repressed cell death. Chrysophanol can impair HBx-induced activation of HSCs via endoplasmic reticulum stress (ER stress) and ferroptosis-dependent and GPX4-independent pathways.


Assuntos
Antraquinonas/farmacologia , Antraquinonas/uso terapêutico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ferroptose/efeitos dos fármacos , Células Estreladas do Fígado/patologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/etiologia , Fitoterapia , Transativadores/efeitos adversos , Proteínas Virais Reguladoras e Acessórias/efeitos adversos , Animais , Antraquinonas/isolamento & purificação , Linhagem Celular , Fibrose , Células Estreladas do Fígado/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo
11.
Toxicol Lett ; 333: 22-32, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32721574

RESUMO

HSCs (hepatic stellate cells) contribute to the excessive extracellular matrix (ECM) deposition, inflammatory pathways and crucial cell-cell interactions in hepatic disease leading to fibrosis. P2x7R is considered a potential orchestrater in liver fibrosis. For this reason, this work explored the role of P2x7R in liver fibrosis and the mechanism by which P2x7R in macrophages promotes fibrogenesis. In a model of liver fibrosis induced by administration of thioacetamide (TAA), inhibition of P2x7R with its selective inhibitor A438079 reversed TAA-induced liver damage and fibrosis. The mechanism was linked to inhibition of P2x7R-NLRP3 inflammasome activation and thereby infiltration of macrophages and neutrophils into the liver. This result indicated that the P2x7R-TLR4-NLRP3 axis is involved in the process of TGF-ß-mediated ECM deposition in HSCs. Ectopic overexpression of P2x7R lowered the threshold of extracellular matrix (ECM) deposition and maintained HSCs in an activated state. The culture medium of THP-1 macrophages stimulated by LPS/ATP aggravated ECM deposition in HSCs by activating P2x7R. Additionally, IL-1ß secreted by LPS / ATP activated macrophages amplified fibrosis. These data indicate that P2x7R plays a key regulative role in the activation and maintenance of HSCs promoted by macrophages. Thus, pharmacological inhibition of P2x7R could be a potential therapeutic mechanism to treat human liver fibrosis.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Células Estreladas do Fígado/efeitos dos fármacos , Cirrose Hepática/metabolismo , Macrófagos Peritoneais/efeitos dos fármacos , Receptores Purinérgicos P2X7/metabolismo , Animais , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Doença Hepática Induzida por Substâncias e Drogas/patologia , Modelos Animais de Doenças , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Retroalimentação Fisiológica , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Humanos , Cirrose Hepática/patologia , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Antagonistas do Receptor Purinérgico P2X/farmacologia , Piridinas/farmacologia , Tetrazóis/farmacologia , Tioacetamida/toxicidade
12.
Life Sci ; 256: 117909, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32512009

RESUMO

Hepatic fibrosis (HF) is a wound-healing response that occurs during chronic liver injury and features by an excessive accumulation of extracellular matrix (ECM) components. Activation of hepatic stellate cell (HSC), the leading effector in HF, is responsible for overproduction of ECM. It has been documented that transforming growth factor-ß1 (TGF-ß1) stimulates superfluous accumulation of ECM and triggers HSCs activation mainly via canonical Smad-dependent pathway. Also, the pro-fibrogenic TGF-ß1 is correlated with generation of reactive oxygen species (ROS) and inhibition of antioxidant mechanisms. Moreover, involvement of oxidative stress (OS) can be clearly elucidated as a fundamental event in liver fibrogenesis. Nuclear factor erythroid 2-related factor 2-antioxidant response elements (Nrf2-AREs) pathway, a group of OS-mediated transcription factors with diverse downstream targets, is associated with the induction of diverse detoxifying enzymes and the most pivotal endogenous antioxidative system. More specifically, Nrf2-AREs pathway has recently assigned as a new therapeutic target for cure of HF. The overall goal of this review will focus on recent findings about activation of Nrf2-AREs-mediated antioxidant and suppression of profibrotic TGF-ß1/Smad3 pathway in the liver, providing an overview of recent advances in transcriptional repressors that dislocated during HF formation, and highlighting possible novel therapeutic targets for liver fibrosis.


Assuntos
Elementos de Resposta Antioxidante/efeitos dos fármacos , Antioxidantes/farmacologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/prevenção & controle , Fator 2 Relacionado a NF-E2/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Antioxidantes/metabolismo , Descoberta de Drogas , Matriz Extracelular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Células Estreladas do Fígado/patologia , Humanos , Fígado/metabolismo , Cirrose Hepática/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
13.
Adv Clin Exp Med ; 29(6): 683-693, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32598580

RESUMO

BACKGROUND: Hepatic fibrosis is a health concern worldwide, and it is of great importance to develop effective therapeutic targets. The small heterodimer partner (SHP) is a regulator of lipid and bile acid metabolism in the liver. OBJECTIVES: The objective of this study was to investigate the contribution of SHP to hepatic fibrosis and the underlying mechanism. MATERIAL AND METHODS: An in vivo rat model of hepatic fibrosis was created through treatment with carbon tetrachloride. We used arginine-glycine-aspartic acid-poly (ethylene glycol)-polyethyleneimine (RGD-PEG-PEI) for the specific transfer of SHP into hepatic stellate cells (HSC). The level of gene expression was detected using quantitative real-time polymerase chain reaction (qRT-PCR). The LX2 cell line was selected for the in vitro assay. Artificial activation of LX2 in vitro was conducted through treatment with platelet-derived growth factor-BB (PDGF-BB), and autophagy was activated using rapamycin. Gain and loss of function assays were performed using a SHP-expressing plasmid or siRNA-SHP. Both qRT-PCR and western blotting were utilized to detect the level of gene expression. RESULTS: RGD-PEG-PEI-mediated the specific transduction of SHP into HSC in the liver and effectively increased the expression of SHP in the rat liver. After treatment with RGD-PEG-PEI-SHP, downregulation of liver fibrosis-associated genes was observed. The results of the in vitro assay indicated that SHP attenuated the stimulating effect of PDGF-BB on the activation of LX2 cells. Overexpression of SHP leads to significant downregulation of HSC activation-associated molecular factors, including α-smooth muscle actin, tissue inhibitor of metalloproteinase-1, and type I collagen. Conversely, increased expression of these molecules could be observed following knockdown of SHP. Furthermore, SHP affected fibrosis by inhibiting autophagy activated through treatment with rapamycin in LX2 cells. Overexpression of SHP may prevent liver fibrogenesis through inhibition of autophagy in HSC. CONCLUSIONS: The SHP may prevent liver fibrogenesis through inhibition of autophagy in HSC. A SHP-targeting therapy-based anti-fibrosis strategy possesses potential for application to the treatment of liver fibrosis.


Assuntos
Autofagia , Células Estreladas do Fígado , Cirrose Hepática , Animais , Tetracloreto de Carbono , Células Estreladas do Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Cirrose Hepática/prevenção & controle , Ratos , Inibidor Tecidual de Metaloproteinase-1
14.
Adv Exp Med Biol ; 1263: 67-84, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32588324

RESUMO

As tumor microenvironments share many of the same qualities as chronic wounds, attention is turning to the wound-repair cells that support the growth of cancerous cells. Stellate cells are star-shaped cells that were first discovered in the perisinusoidal spaces in the liver and have been found to support wound healing by the secretion of growth factors and extracellular matrix. They have since been also found to serve a similar function in the pancreas. In both organs, the wound-healing process may become dysregulated and lead to pathological fibrosis (also known as cirrhosis in the liver). In recent years there has been increasing attention paid to the role of these cells in tumor formation and progression. They may be a factor in initiating the first steps of carcinogenesis such as with liver cirrhosis and hepatocellular carcinoma and also contribute to continued tumor growth, invasion, metastasis, evasion of the immune system, and resistance to chemotherapy, in cancers of both the liver and pancreas. In this chapter we aim to review the structure and function of hepatic and pancreatic stellate cells and their contributions to the tumor microenvironment in their respective cancers and also discuss potential new targets for cancer therapy based on our new understanding of these vital components of the tumor stroma.


Assuntos
Células Estreladas do Fígado/patologia , Neoplasias Hepáticas/patologia , Neoplasias Pancreáticas/patologia , Células Estreladas do Pâncreas/patologia , Microambiente Tumoral , Carcinoma Hepatocelular/patologia , Humanos
15.
PLoS One ; 15(5): e0233702, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32442221

RESUMO

Liver fibrosis is a manifestation of chronic liver injury. It leads to hepatic dysfunction and is a critical element in the pathogenesis of cirrhosis and hepatocellular carcinoma. The activation of hepatic stellate cells (HSC) plays a central role in liver fibrogenesis of different etiologies. To elucidate the molecular mechanism of this phenomenon, it is important to analyze the changes in gene expression that accompany the HSC activation process. In this study, we isolated quiescent and activated HSCs from control mice and mice with CCl4-induced liver fibrosis, respectively, and performed RNA sequencing to compare the differences in gene expression patterns between the two types of HSCs. We also reanalyzed public gene expression data for fibrotic liver tissues isolated from patients with HBV infection, HCV infection, and nonalcoholic fatty liver disease to investigate the gene expression changes during liver fibrosis of these three etiologies. We detected 146 upregulated and 18 downregulated genes in activated HSCs, which were implicated in liver fibrosis as well. Among the overlapping genes, seven transcription factor-encoding genes, ARID5B, GATA6, MITF, PBX1, PLAGL1, SOX4, and SOX9, were upregulated, while one, RXRA, was downregulated. These genes were suggested to play a critical role in HSC activation, and subsequently, in the promotion of liver fibrosis. We undertook the RNA sequencing of quiescent and activated HSCs and analyzed the expression profiles of genes associated with HSC activation in liver fibrotic tissues from different liver diseases, and also aimed to elucidate the changes in gene expression patterns associated with HSC activation and liver fibrosis.


Assuntos
Hepacivirus/metabolismo , Células Estreladas do Fígado/metabolismo , Vírus da Hepatite B/metabolismo , Hepatite B/metabolismo , Hepatite C/metabolismo , Cirrose Hepática/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Animais , Linhagem Celular , Regulação da Expressão Gênica , Células Estreladas do Fígado/patologia , Células Estreladas do Fígado/virologia , Hepatite B/patologia , Hepatite C/patologia , Humanos , Cirrose Hepática/patologia , Masculino , Camundongos , Hepatopatia Gordurosa não Alcoólica/patologia , Fatores de Transcrição/biossíntese
16.
Hum Cell ; 33(3): 582-589, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32449114

RESUMO

Activation of hepatic stellate cells (HSCs) is a prominent driver of liver fibrosis. This study was designed to investigate the effect of exosomes derived from natural killer (NK) cells on HSC activation and liver fibrosis. The exosomes were isolated from NK-92MI cells (NK-Exo) and identified by transmission electron microscopy, nanoparticle tracking analysis, and western blot. Then NK-Exo was administered into TGF-ß1-treated LX-2 cells (human HSC line) and mice with CCl4-induced liver fibrosis. LX-2 cell proliferation was determined by CCK-8 assay. The levels of α-SMA and CoL1A1 were measured by qRT-PCR and western blot to evaluate HSC activation. Serum levels of AST and ALT were measured. Hematoxylin-eosin, Masson staining, and Sirius Red staining were performed to assess the pathological changes and collagen deposition. Cell supernatant derived from NK-92MI cells inhibited TGF-ß1-induced HSC proliferation and activation in LX-2 cells, and this effect was counteracted by the exosome inhibitor GW4869. Further assays confirmed that NK-Exo treatment significantly inhibited TGF-ß1-induced HSC proliferation and activation. Moreover, NK-Exo administration alleviated CCl4-induced liver fibrosis in mice. NK-Exo inhibited TGF-ß1-induced HSC activation and CCl4-induced liver fibrosis.


Assuntos
Exossomos/fisiologia , Células Estreladas do Fígado/patologia , Células Matadoras Naturais/citologia , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Cirrose Hepática/terapia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fator de Crescimento Transformador beta1/efeitos adversos
17.
Nat Cell Biol ; 22(6): 728-739, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32367049

RESUMO

The crosstalk between deregulated hepatocyte metabolism and cells within the tumour microenvironment, as well as the consequent effects on liver tumorigenesis, are not completely understood. We show here that hepatocyte-specific loss of the gluconeogenic enzyme fructose 1,6-bisphosphatase 1 (FBP1) disrupts liver metabolic homeostasis and promotes tumour progression. FBP1 is universally silenced in both human and murine liver tumours. Hepatocyte-specific Fbp1 deletion results in steatosis, concomitant with activation and senescence of hepatic stellate cells (HSCs), exhibiting a senescence-associated secretory phenotype. Depleting senescent HSCs by 'senolytic' treatment with dasatinib/quercetin or ABT-263 inhibits tumour progression. We further demonstrate that FBP1-deficient hepatocytes promote HSC activation by releasing HMGB1; blocking its release with the small molecule inflachromene limits FBP1-dependent HSC activation, the subsequent development of the senescence-associated secretory phenotype and tumour progression. Collectively, these findings provide genetic evidence for FBP1 as a metabolic tumour suppressor in liver cancer and establish a critical crosstalk between hepatocyte metabolism and HSC senescence that promotes tumour growth.


Assuntos
Carcinogênese/patologia , Proliferação de Células , Senescência Celular , Frutose-Bifosfatase/fisiologia , Regulação Neoplásica da Expressão Gênica , Células Estreladas do Fígado/patologia , Neoplasias Hepáticas/patologia , Animais , Carcinogênese/metabolismo , Feminino , Células Estreladas do Fígado/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microambiente Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Life Sci ; 251: 117607, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32240679

RESUMO

BACKGROUND: Arsenic trioxide (ATO) can bind directly to the human promyelocytic leukemia (PML) protein, leading to modification of PML by SUMOs. UBC9 is the only known E2-conjugating enzyme involved in SUMOylation. PML degradation via RNF4, an E3 ubiquitin ligases family member. PML is key organizer of nuclear bodies (NBs) that regulate many biological processes such as senescence, and DNA damage. ATO can activate the TGFß/Smad signaling pathway, causing liver fibrosis. However, the roles of PML Sumoylation in ATO-induced liver fibrosis remain unclear. OBJECTIVE: This study aimed to investigate the role of PML Sumoylation in the ATO-induced HSCs activation and to improve the mechanism of ATO-induced liver fibrosis. METHODS: Hepatic stellate cells (HSCs) were treated with 2 µmol/L ATO. Cell viability was detected by CCK-8 analysis. Immunoblot analysis and real-time quantitative PCR were used to detect the expression of IL-1ß, TNF-α, TGF-ß1, p-Smad2/3, α-SMA, Collagen I and PML SUMOylation after silencing PML, UBC9, and RNF4, respectively. The formation of PML-NBs was observed by immunofluorescence staining. RESULTS: 2 and 5 µmol/L ATO intervention increased HSCs cell viability. ATO was able to significantly trigger PML SUMOylation and the formation of PML-NBs. Inhibition of SUMOylated PML by silencing UBC9, subsequently preventing the downregulation of HSCs activation indicators induced by ATO (P < 0.05). Conversely, enhancing SUMOylated PML accumulation by silencing RNF4, activating TGFß/Smad signaling pathway, eventually promoting the induction of liver fibrosis. CONCLUSION: These results indicated that PML SUMOylation plays a critical role in the development of liver fibrosis induced by ATO.


Assuntos
Trióxido de Arsênio/toxicidade , Células Estreladas do Fígado/patologia , Cirrose Hepática/patologia , Proteína da Leucemia Promielocítica/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Inativação Gênica , Humanos , Proteínas Nucleares/genética , Sumoilação , Fatores de Transcrição/genética , Enzimas de Conjugação de Ubiquitina/genética
19.
Sci Rep ; 10(1): 4546, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32161315

RESUMO

Hepatocellular carcinoma (HCC) is closely associated with liver fibrosis. Hepatic stellate cells (HSC) and cancer-associated myofibroblasts are key players in liver fibrogenesis and hepatocarcinogenesis. Overexpression of fibroblast growth factor (FGF) receptors contributes to HCC development and progression. This study aimed to elucidate the role of FGFs in the HSC-HCC crosstalk. Analysis of the expression of the fifteen paracrine FGF-members revealed that FGF9 was only expressed by HSC but not by HCC cells. Also in human HCC tissues, HSC/stromal myofibroblasts were identified as cellular source of FGF9. High expression levels of FGF9 significantly correlated with poor patient survival. Stimulation with recombinant FGF9 induced ERK- and JNK-activation combined with significantly enhanced proliferation, clonogenicity, and migration of HCC cells. Moreover, FGF9 significantly reduced the sensitivity of HCC cells against sorafenib. Protumorigenic effects of FGF9 on HCC cells were almost completely abrogated by the FGFR1/2/3 inhibitor BGJ398, while the selective FGFR4 inhibitor BLU9931 had no significant effect. In conclusion, these data indicate that stroma-derived FGF9 promotes tumorigenicity and sorafenib resistance of HCC cells and FGF9 overexpression correlates with poor prognosis in HCC patients. Herewith, FGF9 appears as potential prognostic marker and novel therapeutic target in HCC.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/patologia , Fator 9 de Crescimento de Fibroblastos/metabolismo , Regulação Neoplásica da Expressão Gênica , Células Estreladas do Fígado/patologia , Neoplasias Hepáticas/patologia , Acrilamidas/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Movimento Celular , Proliferação de Células , Fator 9 de Crescimento de Fibroblastos/genética , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Prognóstico , Quinazolinas/farmacologia , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/metabolismo , Taxa de Sobrevida , Células Tumorais Cultivadas
20.
Am J Physiol Cell Physiol ; 318(6): C1055-C1064, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32130072

RESUMO

Sphingolipids (SL) are a family of bioactive lipids and a major cellular membrane structural component. SLs include three main compounds: ceramide (Cer), sphingosine (Sp), and sphingosine-1-phosphate (S-1P), all of which have emerging roles in biological functions in cells, especially in the liver. They are under investigation in various liver diseases, including cirrhosis and end-stage liver disease. In this review, we provide an overview on the role of SLs in liver pathobiology and focus on their potential role in the development of hepatic fibrosis. We describe recent evidence and suggest SLs are a promising potential therapeutic target for the treatment of liver disease and fibrosis.


Assuntos
Cirrose Hepática/metabolismo , Fígado/metabolismo , Esfingolipídeos/metabolismo , Animais , Proliferação de Células , Inibidores Enzimáticos/uso terapêutico , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Humanos , Macrófagos do Fígado/metabolismo , Macrófagos do Fígado/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Transdução de Sinais
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