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1.
Mol Med Rep ; 23(5)2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33760163

RESUMO

Tight junction dysregulation and epithelial damage contribute to intestinal barrier loss in patients with acute liver failure (ALF); however, the regulatory mechanisms of these processes remain poorly understood. The aim of the present study was to investigate the changes of intestinal tight junction and intestinal mucosa in mice with ALF and their mechanisms. In the present study, ALF was induced in mice through an intraperitoneal injection of D­galactosamine and lipopolysaccharide (D­GalN/LPS), and the morphological changes of the liver or small intestine were analyzed using hematoxylin and eosin staining, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The intestinal tissues and isolated serum were analyzed using western blotting, immunofluorescence staining and ELISA. D­GalN/LPS­induced mice exhibited signs of hepatocyte necrosis, alongside inflammatory cell infiltration into the liver tissue and partial microvilli detachment in the small intestinal mucosa. TEM demonstrated that the intestinal epithelial tight junctions were impaired, whereas SEM micrographs revealed the presence of abnormal microvilli in D­GalN/LPS­induced mice. In addition, the expression levels of phosphorylated (p)­myosin light chain (MLC), MLC kinase (MLCK) and Rho­associated kinase (ROCK) were significantly increased in the D­GalN/LPS­induced mice compared with those in the control mice, whereas the subsequent inhibition of MLCK or ROCK significantly reduced p­MLC expression levels. Conversely, the expression levels of occludin and zonula occludens­1 (ZO­1) were significantly decreased in the D­GalN/LPS­induced mice, and the inhibition of MLCK or ROCK significantly increased occludin and ZO­1 protein expression levels compared with those in the control group. Changes in the serum levels of tumor necrosis factor­α (TNF­α) and interleukin (IL)­6 were similar to the trend observed in p­MLC expression levels. In conclusion, the findings of the present study suggested that in a D­GalN/LPS­induced ALF model, TNF­α and IL­6 signaling may increase MLCK and ROCK expression levels, further mediate phosphorylation of MLC, which may result in tight junction dysregulation and intestinal barrier dysfunction.


Assuntos
Interleucina-6/genética , Falência Hepática Aguda/genética , Cadeias Leves de Miosina/genética , Fator de Necrose Tumoral alfa/genética , Proteína da Zônula de Oclusão-1/genética , Animais , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestino Delgado/metabolismo , Intestino Delgado/patologia , Falência Hepática Aguda/metabolismo , Falência Hepática Aguda/patologia , Camundongos , Peptídeos/genética , Fosforilação , Transdução de Sinais/genética , Junções Íntimas/genética , Junções Íntimas/metabolismo , Quinases Associadas a rho/genética
2.
Life Sci ; 273: 119304, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33662432

RESUMO

AIMS: Necroptosis, an inflammatory form of regulated necrosis mediated by receptor-interacting kinase 1 (RIP1), RIP3, and pseudokinase mixed lineage kinase domain-like protein (MLKL) is extensively implicated in liver inflammatory disease. Thus identification small-molecule inhibitor of necroptosis has emerged as a potential therapeutic strategy to prevent liver damage. In this study, we identified 5-((7-chloro-6-fluoro-1 h-indol-3-yl) methyl)-3-methylimidazolidine-2,4-dione (F-nec) as a novel potent necroptosis inhibitor. MAIN METHODS: To find out the potent chemical inhibitors of necroptosis, human monocytic U937 cells were treated with a combination of tumor necrosis factor alpha (TNFα) and a pan-caspase inhibitor z-VAD-fmk. LPS and D-galactosamine (LPS/GalN) were further employed to simulate acute liver failure to explore therapeutic potency of F-nec in vivo. In addition, a specific inhibitor of c-Jun NH (2)-terminal kinases (JNK) SP600125 and its activator anisomycin are used to elucidate its mechanisms in acute liver failure therapy. Necroptosis pathway related proteins were tested by western blot. KEY FINDINGS: In this study, we identified F-nec as a novel potent RIP1 inhibitor which efficiently blocked TNFα-induced necroptosis in human and mice cells. Furthermore, pre-treatment of F-nec could prevent hepatic necrosis by reducing RIP1-mediated necroptosis also effectively ameliorated LPS/GalN induced acute liver failure by attenuating cell death signaling-stimulated JNK pathway activation and then suppressing JNK-triggered inflammation. SIGNIFICANCE: Altogether, this study demonstrates that F-nec is a potent inhibitor of RIP1 and highlights its great potential for use in the treatment of RIP1-driven inflammatory liver diseases.


Assuntos
Proteínas Ativadoras de GTPase/antagonistas & inibidores , Galactosamina/toxicidade , Indóis/química , Lipopolissacarídeos/toxicidade , Falência Hepática Aguda/tratamento farmacológico , Necroptose , Substâncias Protetoras/farmacologia , Animais , Humanos , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/metabolismo , Falência Hepática Aguda/patologia , Camundongos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Células U937
3.
Sci Rep ; 10(1): 21850, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33318565

RESUMO

Previous research has revealed that the gut microbiome has a marked impact on acute liver failure (ALF). Here, we evaluated the impact of betaine on the gut microbiota composition in an ALF animal model. The potential protective effect of betaine by regulating Toll-like receptor 4 (TLR4) responses was explored as well. Both mouse and cell experiments included normal, model, and betaine groups. The rat small intestinal cell line IEC-18 was used for in vitro experiments. Betaine ameliorated the small intestine tissue and IEC-18 cell damage in the model group by reducing the high expression of TLR4 and MyD88. Furthermore, the intestinal permeability in the model group was improved by enhancing the expression of the (ZO)-1 and occludin tight junction proteins. There were 509 operational taxonomic units (OTUs) that were identified in mouse fecal samples, including 156 core microbiome taxa. Betaine significantly improved the microbial communities, depleted the gut microbiota constituents Coriobacteriaceae, Lachnospiraceae, Enterorhabdus and Coriobacteriales and markedly enriched the taxa Bacteroidaceae, Bacteroides, Parabacteroides and Prevotella in the model group. Betaine effectively improved intestinal injury in ALF by inhibiting the TLR4/MyD88 signaling pathway, improving the intestinal mucosal barrier and maintaining the gut microbiota composition.


Assuntos
Bactérias/crescimento & desenvolvimento , Betaína/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Intestino Delgado , Falência Hepática Aguda , Receptor 4 Toll-Like/metabolismo , Animais , Bactérias/classificação , Linhagem Celular , Modelos Animais de Doenças , Intestino Delgado/lesões , Intestino Delgado/metabolismo , Intestino Delgado/microbiologia , Falência Hepática Aguda/metabolismo , Falência Hepática Aguda/microbiologia , Falência Hepática Aguda/patologia , Masculino , Camundongos , Ratos
4.
Internist (Berl) ; 61(11): 1151-1162, 2020 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-33006624

RESUMO

Acute liver failure (ALF) is a rare disease with high mortality. It is defined as coagulopathy and encephalopathy in a person with a previously healthy liver. The etiology of ALF is a decisive prognostic factor and varies depending on the country of origin of the patient. Although in many countries the main triggers are hepatotropic viruses, in western industrial countries toxic medicinal causes and autoimmune phenomena predominate. The course of ALF runs through various phases. The complete picture of ALF can mostly no longer be casually treated but necessitates in particular timely contact with a transplantation center. If a causal treatment exists, the effectiveness is greatly dependent on the timing of initiation. In the best case scenario this can completely avoid liver damage. In the complete picture of ALF the main focus is on the intensive medical care of a threatening multiorgan failure. In this context new standards of treatment were established by studies on plasmapheresis.


Assuntos
Falência Hepática Aguda/diagnóstico , Falência Hepática Aguda/terapia , Transplante de Fígado , Cuidados Críticos , Humanos , Falência Hepática Aguda/patologia , Plasmaferese , Doenças Raras , Tempo para o Tratamento
5.
PLoS Pathog ; 16(8): e1008793, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32866189

RESUMO

Transmission to chimpanzees of a precore hepatitis B virus (HBV) mutant implicated in acute liver failure (ALF) in humans did not cause ALF nor the classic form of acute hepatitis B (AHB) seen upon infection with the wild-type HBV strain, but rather a severe AHB with distinct disease features. Here, we investigated the viral and host immunity factors responsible for the unusual severity of AHB associated with the precore HBV mutant in chimpanzees. Archived serial serum and liver specimens from two chimpanzees inoculated with a precore HBV mutant implicated in ALF and two chimpanzees inoculated with wild-type HBV were studied. We used phage-display library and next-generation sequencing (NGS) technologies to characterize the liver antibody response. The results obtained in severe AHB were compared with those in classic AHB and HBV-associated ALF in humans. Severe AHB was characterized by: (i) the highest alanine aminotransferase (ALT) peaks ever seen in HBV transmission studies with a significantly shorter incubation period, compared to classic AHB; (ii) earlier HBsAg clearance and anti-HBs seroconversion with transient or undetectable hepatitis B e antigen (HBeAg); (iii) limited inflammatory reaction relative to hepatocellular damage at the ALT peak with B-cell infiltration, albeit less extensive than in ALF; (iv) detection of intrahepatic germline antibodies against hepatitis B core antigen (HBcAg) by phage-display libraries in the earliest disease phase, as seen in ALF; (v) lack of intrahepatic IgM anti-HBcAg Fab, as seen in classic AHB, but at variance with ALF; and (vi) higher proportion of antibodies in germline configuration detected by NGS in the intrahepatic antibody repertoire compared to classic AHB, but lower than in ALF. This study identifies distinct outcome-specific features associated with severe AHB caused by a precore HBV mutant in chimpanzees, which bear closer resemblance to HBV ALF than to classic AHB. Our data suggest that precore HBV mutants carry an inherently higher pathogenicity that, in addition to specific host factors, may play a critical role in determining the severity of acute HBV disease.


Assuntos
Anticorpos Anti-Hepatite B/metabolismo , Vírus da Hepatite B/metabolismo , Hepatite B/metabolismo , Imunoglobulina M/metabolismo , Falência Hepática Aguda/metabolismo , Animais , Modelos Animais de Doenças , Hepatite B/patologia , Antígenos do Núcleo do Vírus da Hepatite B/metabolismo , Humanos , Falência Hepática Aguda/patologia , Pan troglodytes
6.
Zhonghua Gan Zang Bing Za Zhi ; 28(7): 613-618, 2020 Jul 20.
Artigo em Chinês | MEDLINE | ID: mdl-32791799

RESUMO

Objective: To investigate the mechanism of action of peroxisome proliferator-activated receptor α (PPARα)-mediated CCAAT/enhancer binding protein homologous protein (CHOP) signaling molecule with response to inflammation in mice with acute liver failure. Methods: C57BL/6 mice were used as the research subjects, and D-galactose (D-GalN) combined with lipopolysaccharide (LPS) was injected intraperitoneally to establish a mouse model of acute liver failure. PPARα was activated by Wy-14643. CHOP expression was promoted by plasmids. Liver pathological changes and serum transaminases (ALT and AST) were detected in mice to evaluate liver function. The mRNA expression level of inflammatory factors in liver tissue was detected by real-time fluorescence quantitative PCR. LPS-stimulated macrophage was used to establish an inflammation model. PPARα and CHOP expression was inhibited by siRNA. The mRNA expression level of inflammatory factors in the cells was detected by real-time fluorescence quantitative PCR. Results: Promoted PPARα activation had inhibited liver hemorrhage and inflammation in mice with acute liver failure induced by D-GalN/LPS. In addition, the serum level of transaminases and genetic level of inflammatory factors in liver tissues were reduced (P < 0.01). CHOP accelerated expression had reversed the hepatoprotective effect of PPARα activation, aggravated liver injury, and increased inflammatory factors expression (P < 0.01). At the cellular level, the inhibition of PPARα activation had accelerated the increase of inflammatory factors (P < 0.01), while the inhibition of CHOP activation had all over again decreased the inflammatory factors (P < 0.01). Conclusion: PPARα and CHOP are important signaling molecules to regulate the inflammatory response in acute liver failure and liver injury. PPARα acceleration can down-regulate CHOP to inhibit inflammatory factors, which might play a protective role in mice with acute liver failure.


Assuntos
Falência Hepática Aguda/patologia , PPAR alfa/metabolismo , Fator de Transcrição CHOP/metabolismo , Animais , Inflamação , Lipopolissacarídeos , Fígado , Falência Hepática Aguda/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
7.
Cell Prolif ; 53(6): e12829, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32419317

RESUMO

OBJECTIVE: Acute kidney injury (AKI) is a common complication of acute liver failure (ALF). Pyroptosis is a necrosis type related to inflammation. This study aimed to investigate the role of TNF-α/HMGB1 pathway in pyroptosis during ALF and AKI. METHODS: An ALF and AKI mouse model was generated using LPS/D-Gal, and a TNF-α inhibitor, CC-5013, was used to treat the mice. THP-1 cells were induced to differentiate into M1 macrophages, then challenged with either CC-5013 or an HMGB1 inhibitor, glycyrrhizin. pLVX-mCMVZsGreen-PGK-Puros plasmids containing TNF-α wild-type (WT), mutation A94T of TNF-α and mutation P84L of TNF-α were transfected into M1 macrophages. RESULTS: Treatment with CC-5013 decreased the activation of TNF-α/HMGB1 pathway and pyroptosis in the treated mice and cells compared with the control mice and cells. CC-5013 also ameliorated liver and kidney pathological changes and improved liver and renal functions in treated mice, and the number of M1 macrophages in the liver and kidney tissues also decreased. The activation of TNF-α/HMGB1 pathway and pyroptosis increased in the M1 macrophage group compared with the normal group. Similarly, the activation of TNF-α/HMGB1 pathway and pyroptosis in the LPS + WT group also increased. By contrast, the activation of the TNF-α/HMGB1 pathway and pyroptosis decreased in the LPS + A94T and LPS + P84L groups. Moreover, glycyrrhizin inhibited pyroptosis. CONCLUSION: The TNF-α/HMGB1 inflammation signalling pathway plays an important role in pyroptosis during ALF and AKI.


Assuntos
Lesão Renal Aguda/metabolismo , Proteína HMGB1/fisiologia , Falência Hepática Aguda/metabolismo , Piroptose , Fator de Necrose Tumoral alfa/fisiologia , Lesão Renal Aguda/sangue , Lesão Renal Aguda/imunologia , Lesão Renal Aguda/patologia , Animais , Diferenciação Celular/efeitos dos fármacos , Ácido Glicirrízico/farmacologia , Proteína HMGB1/antagonistas & inibidores , Proteína HMGB1/sangue , Proteína HMGB1/metabolismo , Humanos , Inflamação/metabolismo , Lenalidomida/farmacologia , Falência Hepática Aguda/sangue , Falência Hepática Aguda/imunologia , Falência Hepática Aguda/patologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Polimorfismo de Nucleotídeo Único , Piroptose/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Células THP-1 , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/genética
8.
Sci Rep ; 10(1): 6752, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32317688

RESUMO

Few reports describe oxysterols in healthy children or in children with liver disease. We aimed to determine whether developmental changes in urinary and serum oxysterols occur during childhood, and to assess whether oxysterols might be biomarkers for pediatric liver disease. Healthy children enrolled as subjects (36 and 35 for urine and serum analysis, respectively) included neonates, infants, preschoolers, and school-age children, studied along with 14 healthy adults and 8 children with liver disease. We quantitated 7 oxysterols including 4ß-, 20(S)-, 22(S)-, 22(R)-, 24(S)-, 25-, and 27-hydroxycholesterol using liquid chromatography/electrospray ionization-tandem mass spectrometry. Urinary total oxysterols were significantly greater in neonates than in infants (P < 0.05), preschoolers (P < 0.001), school-age children (P < 0.001), or adults (P < 0.001), declining with age. Serum total oxysterols in neonates were significantly lower than in infants (P < 0.05), preschoolers (P < 0.001), school-age children (P < 0.05), or adults (P < 0.01). Compared with healthy children, total oxysterols and 24(S)-hydroxycholesterol in liver disease were significantly increased in both urine (P < 0.001 and P < 0.001, respectively) and serum (P < 0.001 and P < 0.05, respectively). Oxysterols in liver disease, particularly 24(S)-hydroxycholesterol, were greater in urine than serum. Oxysterols change developmentally and might serve as a biomarker for pediatric liver disease. To our knowledge, this is the first such report.


Assuntos
Atresia Biliar/diagnóstico , Cisto do Colédoco/diagnóstico , Colestase Intra-Hepática/diagnóstico , Hepatite Autoimune/diagnóstico , Falência Hepática Aguda/diagnóstico , Oxisteróis , Adolescente , Adulto , Fatores Etários , Atresia Biliar/sangue , Atresia Biliar/patologia , Atresia Biliar/urina , Biomarcadores/sangue , Biomarcadores/urina , Estudos de Casos e Controles , Criança , Pré-Escolar , Cisto do Colédoco/sangue , Cisto do Colédoco/patologia , Cisto do Colédoco/urina , Colestase Intra-Hepática/sangue , Colestase Intra-Hepática/patologia , Colestase Intra-Hepática/urina , Feminino , Hepatite Autoimune/sangue , Hepatite Autoimune/patologia , Hepatite Autoimune/urina , Humanos , Lactente , Recém-Nascido , Fígado/metabolismo , Fígado/patologia , Falência Hepática Aguda/sangue , Falência Hepática Aguda/patologia , Falência Hepática Aguda/urina , Masculino , Pessoa de Meia-Idade , Oxisteróis/sangue , Oxisteróis/urina , Espectrometria de Massas por Ionização por Electrospray
9.
Sci Rep ; 10(1): 5124, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32198411

RESUMO

Drug-induced liver injury (DILI) is a frequent cause of liver injury and acute liver failure. We aimed to review all hospitalized DILI cases in a tertiary Egyptian center from January 2015 through January 2016. Cases with elevated alanine aminotransferase more than 3-fold and/or alkaline phosphatase more than 2-fold the upper limit of normal value were prospectively recruited and followed for one year. Drug history, liver biopsy whenever feasible and application of Roussel Uclaf Causality Assessment Method (RUCAM) were the diagnostic prerequisites after exclusion of other etiologies of acute liver injury. In order of frequency, the incriminated drugs were: Diclofenac (31 cases, 41.3%), amoxicillin-clavulanate (14 cases, 18.7%), halothane toxicity (8 cases, 10.7%), ibuprofen (4 cases, 5.3%), Khat (3 cases, 4%), tramadol (3 cases, 4%), Sofosbuvir with ribavirin (2 cases, 2.7%), and acetylsalicylic acid (2 cases, 2.7%) with one offending drug in 93.3% of cases. Forty-four cases (58.7%) were males; while 56 cases (74.7%) had HCV related chronic liver disease. Thirty-two cases (42.7%) presented with pattern of hepatocellular injury, while 23 cases (30.7%) were with cholestasis, and 20 cases (20.7%) with a mixed hepatocellular/cholestatic injury. One case received a transplant (0.75%), 7 cases died (9.3%), 23 cases (30.6%) developed liver decompensation (hepatic encephalopathy and ascites), and 44 cases completely resolved (58.7%). In conclusion, Diclofenac is the commonest offender in DILI occurrence in an Egyptian cohort. Age and prothrombin concentration were the only predictors of unfavorable outcomes of DILI.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/patologia , Colestase/patologia , Encefalopatia Hepática/patologia , Falência Hepática Aguda/patologia , Fígado/patologia , Adulto , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Combinação Amoxicilina e Clavulanato de Potássio/efeitos adversos , Antibacterianos/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/mortalidade , Colestase/induzido quimicamente , Inibidores de Ciclo-Oxigenase/efeitos adversos , Diclofenaco/efeitos adversos , Egito , Feminino , Encefalopatia Hepática/induzido quimicamente , Humanos , Fígado/efeitos dos fármacos , Falência Hepática Aguda/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Centros de Atenção Terciária
10.
Int Immunopharmacol ; 80: 106196, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31978803

RESUMO

Sepsis-induced liver injury is very common in intensive care units. Here, we investigated the effects of 6-gingerol on sepsis-induced liver injury and the role of the Nrf2 pathway in this process. 6-Gingerol is the principal ingredient of ginger that exerts anti-inflammatory and antioxidant effects. Using cecal ligation and puncture (CLP) to induce polymicrobial sepsis and related liver injury, we found that mice pre-treated with 6-Gingerol showed less incidences of severe liver inflammation and death than untreated CLP groups. 6-Gingerol administration also inhibited the expression of pyroptosis-related proteins, including NOD-like receptor protein 3 (NLRP3), IL-1ß, and caspase-1. Consistent with these findings, 6-gingerol reduced the effects of pyroptosis induced by lipopolysaccharide (LPS) and adenosine 5'-triphosphate (ATP) in RAW 264.7 cells, as evidenced by IL-1ß and caspase-1 protein levels in the supernatant and propidium iodide (PI) staining. 6-Gingerol was shown to activate the Nrf2 pathway in vivo and in vitro. Notably, Nrf2 siRNA transfection nullified the inhibitory effects of 6-gingerol on pyroptosis in vitro. In summary, these findings suggested that 6-gingerol alleviated sepsis-induced liver injury by inhibiting pyroptosis through the Nrf2 pathway.


Assuntos
Catecóis/farmacologia , Álcoois Graxos/farmacologia , Falência Hepática Aguda/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Sepse/complicações , Transdução de Sinais/efeitos dos fármacos , Animais , Catecóis/uso terapêutico , Modelos Animais de Doenças , Álcoois Graxos/uso terapêutico , Técnicas de Silenciamento de Genes , Humanos , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/patologia , Falência Hepática Aguda/imunologia , Falência Hepática Aguda/patologia , Masculino , Camundongos , Fator 2 Relacionado a NF-E2/genética , Piroptose/efeitos dos fármacos , Piroptose/imunologia , Células RAW 264.7 , RNA Interferente Pequeno/metabolismo , Sepse/imunologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia
11.
Am J Pathol ; 190(2): 347-357, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31734229

RESUMO

Severe hepatic insults can lead to acute liver failure and hepatic encephalopathy (HE). Transforming growth factor ß1 (TGFß1) has been shown to contribute to HE during acute liver failure; however, TGFß1 must be activated to bind its receptor and generate downstream effects. One protein that can activate TGFß1 is thrombospondin-1 (TSP-1). Therefore, the aim of this study was to assess TSP-1 during acute liver failure and HE pathogenesis. C57Bl/6 or TSP-1 knockout (TSP-1-/-) mice were injected with azoxymethane (AOM) to induce acute liver failure and HE. Liver damage, neurologic decline, and molecular analyses of TSP-1 and TGFß1 signaling were performed. AOM-treated mice had increased TSP-1 and TGFß1 mRNA and protein expression in the liver. TSP-1-/- mice administered AOM had reduced liver injury as assessed by histology and serum transaminase levels compared with C57Bl/6 AOM-treated mice. TSP-1-/- mice treated with AOM had reduced TGFß1 signaling that was associated with less hepatic cell death as assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining and cleaved caspase 3 expression. TSP-1-/- AOM-treated mice had a reduced rate of neurologic decline, less cerebral edema, and a decrease in microglia activation in comparison with C57Bl/6 mice treated with AOM. Taken together, TSP-1 is an activator of TGFß1 signaling during AOM-induced acute liver failure and contributes to both liver pathology and HE progression.


Assuntos
Modelos Animais de Doenças , Encefalopatia Hepática/patologia , Falência Hepática Aguda/patologia , Trombospondina 1/fisiologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Azoximetano/toxicidade , Carcinógenos/toxicidade , Morte Celular , Encefalopatia Hepática/etiologia , Encefalopatia Hepática/metabolismo , Falência Hepática Aguda/etiologia , Falência Hepática Aguda/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais
12.
Immunol Cell Biol ; 98(1): 54-66, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31625631

RESUMO

Although the detrimental effects of diabetes mellitus/hyperglycemia have been observed in many liver disease models, the function and mechanism of hyperglycemia regulating liver-resident macrophages, Kupffer cells (KCs), in thioacetamide (TAA)-induced liver injury remain largely unknown. In this study, we evaluated the role of hyperglycemia in regulating NOD-like receptor family pyrin domain-containing 3 protein (NLRP3) inflammasome activation by inhibiting autophagy induction in KCs in the TAA-induced liver injury model. Type I diabetes/hyperglycemia was induced by streptozotocin treatment. Compared with the control group, hyperglycemic mice exhibited a significant increase in intrahepatic inflammation and liver injury. Enhanced NLRP3 inflammasome activation was detected in KCs from hyperglycemic mice, as shown by increased gene induction and protein levels of NLRP3, cleaved caspase-1, apoptosis-associated speck-like protein containing a caspase recruitment domain and interleukin-1ß, compared with control mice. NLRP3 inhibition by its antagonist CY-09 effectively suppressed inflammasome activation in KCs and attenuated liver injury in hyperglycemic mice. Furthermore, inhibited autophagy activation was revealed by transmission electron microscope detection, decreased LC3B protein expression and p-62 protein degradation in KCs isolated from TAA-stressed hyperglycemic mice. Interestingly, inhibited 5' AMP-activated protein kinase (AMPK) but enhanced mammalian target of rapamycin (mTOR) activation was found in KCs from TAA-stressed hyperglycemic mice. AMPK activation by its agonist 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) or mTOR signaling knockdown by small interfering RNA restored autophagy activation, and subsequently, inhibited NLRP3 inflammasome activation in KCs, leading to ultimately reduced TAA-induced liver injury in the hyperglycemic mice. Our findings demonstrated that hyperglycemia aggravated TAA-induced acute liver injury by promoting liver-resident macrophage NLRP3 inflammasome activation via inhibiting AMPK/mTOR-mediated autophagy. This study provided a novel target for prevention of toxin-induced acute liver injury under hyperglycemia.


Assuntos
Proteínas Quinases Ativadas por AMP/imunologia , Morte Celular Autofágica/imunologia , Hiperglicemia/imunologia , Inflamassomos/imunologia , Falência Hepática Aguda/imunologia , Macrófagos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Transdução de Sinais/imunologia , Serina-Treonina Quinases TOR/imunologia , Animais , Hiperglicemia/patologia , Falência Hepática Aguda/patologia , Macrófagos/patologia , Masculino , Camundongos
14.
World J Gastroenterol ; 25(44): 6527-6540, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31802832

RESUMO

BACKGROUND: Massive hepatocyte death is the core event in acute liver failure (ALF). Gasdermin D (GSDMD)-mediated pyroptosis is a type of highly inflammatory cell death. However, the role of hepatocyte pyroptosis and its mechanisms of expanding inflammatory responses in ALF are unclear. AIM: To investigate the role and mechanisms of GSDMD-mediated hepatocyte pyroptosis through in vitro and in vivo experiments. METHODS: The expression of pyroptosis pathway-associated proteins in liver tissues from ALF patients and a hepatocyte injury model was examined by Western blot. GSDMD short hairpin RNA (shRNA) was used to investigate the effects of downregulation of GSDMD on monocyte chemotactic protein 1 (MCP1) and its receptor CC chemokine receptor-2 (CCR2) in vitro. For in vivo experiments, we used GSDMD knockout mice to investigate the role and mechanism of GSDMD in a D-galactose/lipopolysaccharide (D-Galn/LPS)-induced ALF mouse model. RESULTS: The levels of pyroptosis pathway-associated proteins in liver tissue from ALF patients and a hepatocyte injury model increased significantly. The level of GSDMD-N protein increased most obviously (P < 0.001). In vitro, downregulation of GSDMD by shRNA decreased the cell inhibition rate and the levels of MCP1/CCR2 proteins (P < 0.01). In vivo, GSDMD knockout dramatically eliminated inflammatory damage in the liver and improved the survival of D-Galn/LPS-induced ALF mice (P < 0.001). Unlike the mechanism of immune cell pyroptosis that involves releasing interleukin (IL)-1ß and IL-18, GSDMD-mediated hepatocyte pyroptosis recruited macrophages via MCP1/CCR2 to aggravate hepatocyte death. However, this pathological process was inhibited after knocking down GSDMD. CONCLUSION: GSDMD-mediated hepatocyte pyroptosis plays an important role in the pathogenesis of ALF, recruiting macrophages to release inflammatory mediators by upregulating MCP1/CCR2 and leading to expansion of the inflammatory responses. GSDMD knockout can reduce hepatocyte death and inflammatory responses, thus alleviating ALF.


Assuntos
Hepatócitos/patologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Falência Hepática Aguda/imunologia , Macrófagos/imunologia , Proteínas de Ligação a Fosfato/metabolismo , Piroptose/imunologia , Animais , Linhagem Celular , Quimiocina CCL2/metabolismo , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Hepatócitos/imunologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/patologia , Masculino , Camundongos , Camundongos Knockout , Proteínas de Ligação a Fosfato/genética , RNA Interferente Pequeno/metabolismo , Receptores CCR2/metabolismo , Transdução de Sinais/imunologia , Regulação para Cima
15.
J Vis Exp ; (153)2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31840655

RESUMO

Acute liver failure (ALF) is a clinical condition caused by various etiologies resulting in the loss of metabolic, biochemical, synthesizing, and detoxifying functions of the liver. In most irreversible liver damage cases, orthotropic liver transplant (OLT) remains the only available treatment. To study the therapeutic potential of a treatment for ALF, its prior testing in an animal model of ALF is essential. In the current study, an ALF model in rats was developed by combining 70% partial hepatectomy (PHx) and injections of acetaminophen (APAP) that provides a therapeutic window of 48 h. The median and left lateral lobes of the liver were removed to excise 70% of the liver mass and APAP was given 24 h postsurgically for 2 days. Survival in ALF-induced animals was found to be severely decreased. The development of ALF was confirmed by altered serum levels of the enzymes alanine amino transferase (ALT), aspartate amino transferase (AST), alkaline phosphatase (ALP); changes in prothrombin time (PT); and assessment of the international normalized ratio (INR). Study of the gene expression profile by qPCR revealed an increase in expression levels of genes involved in apoptosis, inflammation, and in the progression of liver injury. Diffused degeneration of hepatocytes and infiltration of immune cells was observed by histological evaluation. The reversibility of ALF was confirmed by the restoration of survival and serum levels of ALT, AST, and ALP after intrasplenic transplantation of syngeneic healthy rat hepatocytes. This model presents a reliable alternative to the available ALF animal models to study the pathophysiology of ALF as well as to evaluate the potential of a novel therapy for ALF. The use of two different approaches also makes it possible to study the combined effect of physical and drug-induced liver injury. The reproducibility and feasibility of current procedure is an added benefit of the model.


Assuntos
Acetaminofen/toxicidade , Modelos Animais de Doenças , Hepatectomia/efeitos adversos , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/etiologia , Fígado/cirurgia , Analgésicos não Entorpecentes/toxicidade , Animais , Hepatócitos/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Falência Hepática Aguda/patologia , Masculino , Ratos , Ratos Wistar , Reprodutibilidade dos Testes
16.
Comb Chem High Throughput Screen ; 22(9): 649-656, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31692440

RESUMO

BACKGROUND AND OBJECTIVE: Swertia mussotii Franch, also known as "Zangyinchen", is one of a Tibetan traditional herb used for treatment of liver diseases over thousands of years at Qinghai-Tibet Plateau, has been confirmed to be hepatoprotective. However, the underlying mechanism is largely unknown. MATERIALS AND METHODS: In this study, we evaluated the effect of S. mussotii treatment in a carbon tetrachloride-induced acute liver injury rat model by examining the serum alanine aminotransferase, aspartate aminotransferase, total bilirubin levels and performing histological observations of the liver tissues. Meanwhile, the metabolomics analysis was used to explore the molecular mechanism of S. mussotii treatment by high performance liquid chromatography tandem mass spectrometry. RESULTS: The results showed that S. mussotii treatment could effectively improve the serum alanine aminotransferase, aspartate aminotransferase, total bilirubin in acute liver injury rat model. Histological observation showed that S. mussotii treatment could effectively alleviate liver injury. Moreover, the metabolomics analysis showed that S. mussotii treatment could normalize the levels of many fatty acid metabolism related metabolites. And the results of pathway analysis showed that these metabolites significantly enriched in fatty acid biosynthesis pathway (myristic acid, dodecanoic acid and capric acid) and linoleic acid metabolism pathway (13-OxoODE). CONCLUSION: The results indicated that S. mussotii treatment could significantly improve acute liver injury through affecting the pathways related to lipid metabolism.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Falência Hepática Aguda/tratamento farmacológico , Fígado/efeitos dos fármacos , Substâncias Protetoras/uso terapêutico , Swertia/química , Animais , Tetracloreto de Carbono/administração & dosagem , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Ensaios de Triagem em Larga Escala , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/patologia , Masculino , Substâncias Protetoras/química , Substâncias Protetoras/isolamento & purificação , Ratos , Ratos Wistar
17.
Pediatr Infect Dis J ; 38(10): 1035-1037, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31568141

RESUMO

Isavuconazole is a new azole approved for adults with invasive aspergillosis and mucormycosis, with a favorable hepatic tolerability reported in Phase III trials. Here, we report on a case of drug-induced liver failure related to isavuconazole in a pediatric patient treated for invasive aspergillosis after bone marrow transplant.


Assuntos
Antifúngicos/efeitos adversos , Aspergilose Pulmonar Invasiva/complicações , Aspergilose Pulmonar Invasiva/tratamento farmacológico , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/patologia , Nitrilos/efeitos adversos , Piridinas/efeitos adversos , Triazóis/efeitos adversos , Adolescente , Antifúngicos/administração & dosagem , Transplante de Medula Óssea/efeitos adversos , Humanos , Masculino , Nitrilos/administração & dosagem , Piridinas/administração & dosagem , Triazóis/administração & dosagem
18.
Stem Cell Res Ther ; 10(1): 230, 2019 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-31615539

RESUMO

BACKGROUND: Systemic inflammatory response syndrome (SIRS) is common in severe fulminant hepatic failure (FHF) and has a high mortality rate (20-50%) due to irreversible cerebral edema or sepsis. Stem cell-based treatment has emerged as a promising alternative therapeutic strategy to prolong the survival of patients suffering from FHF via the inhibition of SIRS due to their immunomodulatory effects. METHODS: 3D spheroids of adipose-derived mesenchymal stem cells (3D-ADSC) were prepared by the hanging drop method. The efficacy of the 3D-ADSC to rescue FHF was evaluated in a D-galactosamine/lipopolysaccharide (GalN/LPS)-induced mouse model of FHF via intraportal transplantation of the spheroids. RESULTS: Intraportally delivered 3D-ADSC better engrafted and localized into the damaged livers compared to 2D-cultured adipose-derived mesenchymal stem cells (2D-ADSC). Transplantation of 3D-ADSC rescued 50% of mice from FHF-induced lethality, whereas only 20% of mice survived when 2D-ADSC were transplanted. The improved transplantation outcomes correlated with the enhanced immunomodulatory effect of 3D-ADSC in the liver microenvironment. CONCLUSION: The study shows that the transplantation of optimized 3D-ADSC can efficiently ameliorate GalN/LPS-induced FHF due to improved viability, resistance to exogenous ROS, and enhanced immunomodulatory effects of 3D-ADSC.


Assuntos
Falência Hepática Aguda/terapia , Fígado/patologia , Transplante de Células-Tronco Mesenquimais , Animais , Técnicas de Cultura de Células , Sobrevivência Celular , Dinoprostona/metabolismo , Modelos Animais de Doenças , Galactosamina/toxicidade , Heme Oxigenase-1/metabolismo , Interleucina-10/sangue , Lipopolissacarídeos/toxicidade , Fígado/metabolismo , Falência Hepática Aguda/patologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Nus , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
19.
ACS Appl Mater Interfaces ; 11(43): 39574-39585, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31589019

RESUMO

In the past few decades, intracellular calcium overload has been shown to induce cell death through multiple signaling pathways. In this study, we used BAPTA-AM, a well-known membrane-permeable Ca2+ chelator, to prevent cell injury by allaying the intracellular calcium overload. We explored the clinical potentials of BAPTA-AM-loaded liposome (BAL) in the treatment of the acute liver failure (ALF) mouse model, which is characterized by severe hepatic necrosis and apoptosis. We discovered that BAL can significantly inhibit D-GalN-induced LO2 cell damage as it increased cell viability by 60% and downregulated the LPS-stimulated inflammatory response in RAW 264.7 macrophages by reversing the morphological change and modulating TNF-α and NF-κB expressions. Through systemic administration, BAL can rapidly accumulate in damaged liver tissue and exhibit excellent treatment effects on the D-GalN/LPS-induced ALF mouse model, including elevation of the survival rate (from 10 to 80%), recovery of normal liver indexes and liver health indicators, improvement of liver blood microcirculation (increased the blood flow volume by 80% and flow rate by 60%), and blood coagulation. The underlying hepatoprotective effect of BAL is presumably based on the antinecrosis and antiapoptosis abilities attributed to its inhibition on oxidative stress, restriction on TNF-α receptor, and mitochondria-mediated apoptotic pathway by effectively clearing the overloaded intercellular calcium. BAL holds great potential as a new therapeutic strategy for ALF treatment, and its prominent cell rescue ability provides ample opportunities for the treatment of many other diseases that are characterized by rapid and massive cell damage.


Assuntos
Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Ácido Egtázico/análogos & derivados , Falência Hepática Aguda , Animais , Ácido Egtázico/química , Ácido Egtázico/farmacologia , Lipopolissacarídeos/toxicidade , Lipossomos , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/tratamento farmacológico , Falência Hepática Aguda/metabolismo , Falência Hepática Aguda/patologia , Camundongos , Camundongos Endogâmicos ICR , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/patologia , NF-kappa B/metabolismo , Células RAW 264.7 , Fator de Necrose Tumoral alfa/metabolismo
20.
Life Sci ; 238: 116976, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31634464

RESUMO

AIM: The purpose of the present study was to elucidate the protective effect of histone deacetylase 6 inhibitor ACY1215 on autophagy pathway in acute liver failure (ALF). MAIN METHODS: Lipopolysaccharide (LPS) and d-galactosamine (D-Gal) were used to induce ALF model in C57BL/6 mice. D-Gal and tumor necrosis factor alpha (TNF-α) were applied in L02 cell. Autophagy inhibitor 3-MA and ACY1215 were conducted to induce 3-MA group, ACY1215 group and ACY1215+3-MA group. RESULTS: ACY1215 improved liver histological and functional changes in ALF mice model, whereas the autophagy inhibitor 3-MA aggravated liver tissue pathological and functional damage in ALF mice model group. The apoptotic levels (including apoptotic index/rate and apoptotic proteins) in ALF mice and L02 cell were ameliorated with treatment ACY1215. 3-MA accentuated the apoptotic levels in ACY1215 group. D-Gal/TNF-α could reduce L02 cell mitochondrial membrane potential (ΔΨm) in control group. ACY1215 increased the ΔΨm in ALF model. 3-MA also further reduced the ΔΨm in ACY1215 group. ACY1215 could induce autophagy in ALF mice and cell model group accompanied with an increase in expression of LC3-II and beclin-1 proteins and down-regulation of p62 protein. Moreover, the expression of LC3-II and beclin1 proteins were greatly reduced and the expression of p62 protein was ascended after intervention with 3-MA in ACY1215 group. SIGNIFICANCE: Histone deacetylase 6 inhibitor ACY1215 could protect acute liver failure mice and L02 cell by inhibiting apoptosis pathway through enhancing autophagy way.


Assuntos
Autofagia , Desacetilase 6 de Histona/antagonistas & inibidores , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Falência Hepática Aguda/prevenção & controle , Substâncias Protetoras/farmacologia , Pirimidinas/farmacologia , Animais , Apoptose , Autofagia/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Lipopolissacarídeos/toxicidade , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/metabolismo , Falência Hepática Aguda/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais
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