RESUMO
PURPOSE: This study aimed to define the genotypic and phenotypic spectrum of reversible acute liver failure (ALF) of infancy resulting from biallelic pathogenic TRMU variants and determine the role of cysteine supplementation in its treatment. METHODS: Individuals with biallelic (likely) pathogenic variants in TRMU were studied within an international retrospective collection of de-identified patient data. RESULTS: In 62 individuals, including 30 previously unreported cases, we described 47 (likely) pathogenic TRMU variants, of which 17 were novel, and 1 intragenic deletion. Of these 62 individuals, 42 were alive at a median age of 6.8 (0.6-22) years after a median follow-up of 3.6 (0.1-22) years. The most frequent finding, occurring in all but 2 individuals, was liver involvement. ALF occurred only in the first year of life and was reported in 43 of 62 individuals; 11 of whom received liver transplantation. Loss-of-function TRMU variants were associated with poor survival. Supplementation with at least 1 cysteine source, typically N-acetylcysteine, improved survival significantly. Neurodevelopmental delay was observed in 11 individuals and persisted in 4 of the survivors, but we were unable to determine whether this was a primary or a secondary consequence of TRMU deficiency. CONCLUSION: In most patients, TRMU-associated ALF was a transient, reversible disease and cysteine supplementation improved survival.
Assuntos
Falência Hepática Aguda , Falência Hepática , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Adulto Jovem , Acetilcisteína/uso terapêutico , Falência Hepática/tratamento farmacológico , Falência Hepática/genética , Falência Hepática Aguda/tratamento farmacológico , Falência Hepática Aguda/genética , Proteínas Mitocondriais/genética , Mutação , Estudos Retrospectivos , tRNA Metiltransferases/genéticaRESUMO
This study aimed to investigate the therapeutic potential of human umbilical cord mesenchymal stem cells derived exosomes (hUCMSC-Exo) in acute liver failure (ALF) in mice as well as its underlying mechanism. We found that a single tail vein administration of hucMSC-Exo effectively enhanced the survival rate, inhibited apoptosis in hepatocytes, and improved liver function in APAP-induced mouse model of ALF. Furthermore, the deletion of glutathione (GSH) and superoxide dismutase (SOD), generation of malondialdehyde (MDA), and the over production of cytochrome P450 E1 (CYP2E1) and 4-hydroxynonenal (4-HNE) caused by APAP were also inhibited by hucMSC-Exo, indicating that hucMSC-Exo inhibited APAP-induced apoptosis of hepatocytes by reducing oxidative stress. Moreover, hucMSC-Exo significantly down-regulated the levels of inflammatory cytokines IL-6, IL-1ß, and TNF-α in APAP-treated livers. Western blot showed that hucMSC-Exo significantly promoted the activation of ERK1/2 and IGF-1R/PI3K/AKT signaling pathways in APAP-injured LO2 cells, resulting in the inhibition of apoptosis of LO2 cells. Importantly, PI3K inhibitor LY294002 and ERK1/2 inhibitor PD98059 could reverse the function of hucMSC-Exo on APAP-injured LO2 cells in some extent. Our results suggest that hucMSC-Exo offer antioxidant hepatoprotection against APAP in vitro and in vivo by inhibitiing oxidative stress-induced apoptosis via upregulation of ERK1/2 and PI3K/AKT signaling pathways.
Assuntos
Acetaminofen/efeitos adversos , Exossomos/fisiologia , Falência Hepática/induzido quimicamente , Falência Hepática/genética , Sistema de Sinalização das MAP Quinases/genética , Células-Tronco Mesenquimais/citologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais/genética , Cordão Umbilical/citologia , Animais , Apoptose/genética , Células Cultivadas , Modelos Animais de Doenças , Hepatócitos/patologia , Humanos , Falência Hepática/patologia , Camundongos , Estresse Oxidativo/genéticaRESUMO
BACKGROUND: Wilson's disease is a genetic disorder inherited in a recessive manner, caused by mutations in the copper-transporter ATP7B. Although it is a well-known disease, currently available treatments are far from satisfactory and their efficacy varies in individual patients. Due to the lack of information about drug-metabolizing enzymes and drug transporters profile in Wilson's disease livers, we aimed to evaluate the mRNA expression and protein abundance of selected enzymes and drug transporters in this liver disorder. METHODS: We analyzed gene expression (qPCR) and protein abundance (LC-MS/MS) of 14 drug-metabolizing enzymes and 16 drug transporters in hepatic tissue from Wilson's disease patients with liver failure (n = 7, Child-Pugh class B and C) and metastatic control livers (n = 20). RESULTS: In presented work, we demonstrated a downregulation of majority of CYP450 and UGT enzymes. Gene expression of analyzed enzymes ranged between 18 and 65% compared to control group and significantly lower protein content of CYP1A1, CYP1A2, CYP2C8, CYP2C9, CYP3A4 and CYP3A5 enzymes was observed in Wilson's disease. Moreover, a general decrease in hepatocellular uptake carriers from SLC superfamily (significant at protein level for NTCP and OATP2B1) was observed. As for ABC transporters, the protein abundance of BSEP and MRP2 was significantly lower, while levels of P-gp and MRP4 transporters were significantly higher in Wilson's disease. CONCLUSIONS: Altered hepatic expression of drug-metabolizing enzymes and drug transporters in Wilson's disease patients with liver failure may result in changes of drug pharmacokinetics in that group of patients.
Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Degeneração Hepatolenticular/metabolismo , Falência Hepática/metabolismo , Fígado/enzimologia , Preparações Farmacêuticas/metabolismo , Adulto , Idoso , Proteínas de Transporte , Sistema Enzimático do Citocromo P-450/genética , Regulação para Baixo , Feminino , Degeneração Hepatolenticular/genética , Humanos , Fígado/patologia , Falência Hepática/genética , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Adulto JovemRESUMO
TRMU is a nuclear gene crucial for mitochondrial DNA translation by encoding tRNA 5-methylaminomethyl-2-thiouridylate methyltransferase, which thiolates mitochondrial tRNA. Biallelic pathogenic variants in TRMU are associated with transient infantile liver failure. Other less common presentations such as Leigh syndrome, myopathy, and cardiomyopathy have been reported. Recent studies suggested that provision of exogenous L-cysteine or N-acetylcysteine may ameliorate the effects of disease-causing variants and improve the natural history of the disease. Here, we report six infants with biallelic TRMU variants, including four previously unpublished patients, all treated with exogenous cysteine. We highlight the first report of an affected patient undergoing orthotopic liver transplantation, the long-term effects of cysteine supplementation, and the ability of the initial presentation to mimic multiple inborn errors of metabolism. We propose that TRMU deficiency should be suspected in all children presenting with persistent lactic acidosis and hypoglycemia, and that combined N-acetylcysteine and L-cysteine supplementation should be considered prior to molecular diagnosis, as this is a low-risk approach that may increase survival and mitigate the severity of the disease course.
Assuntos
Doença de Leigh/terapia , Falência Hepática/terapia , Proteínas Mitocondriais/genética , Biossíntese de Proteínas , tRNA Metiltransferases/genética , Acetilcisteína/administração & dosagem , Acetilcisteína/metabolismo , Acidose/genética , Acidose/metabolismo , Cisteína/administração & dosagem , Cisteína/metabolismo , DNA Mitocondrial/genética , Feminino , Humanos , Lactente , Doença de Leigh/genética , Doença de Leigh/metabolismo , Doença de Leigh/patologia , Falência Hepática/genética , Falência Hepática/metabolismo , Falência Hepática/patologia , Transplante de Fígado/métodos , Masculino , Mitocôndrias/enzimologia , Proteínas Mitocondriais/deficiência , RNA de Transferência/genética , tRNA Metiltransferases/deficiênciaRESUMO
Infantile liver failure syndrome type 1 (ILFS1) is a recently recognized autosomal recessive disorder caused by deleterious mutations in the leucyl-tRNA synthetase 1 gene (LARS1). The LARS1 enzyme is responsible for incorporation of the amino acid leucine during protein polypeptide synthesis. Individuals with LARS1 mutations typically show liver failure from infancy to early childhood during periods of illness or other physiological stress. While 25 patients from 15 families with ILFS1 have been reported in the literature, histological reports from autopsy findings are limited. We report here a premature male neonate who presented with severe intrauterine growth retardation, microcytic anemia, and fulminant liver failure, and who was a compound heterozygote for two novel deleterious mutations in LARS1. An autopsy showed fulminant hepatitis-like hepatocellular injury and fibrogenesis in the liver and a lack of uniformity in skeletal muscle, accompanied by the disruption of striated muscle fibers. Striking dysgenesis in skeletal muscle detected in the present case indicates the effect of LARS1 functional deficiency on the musculature. Whole-exome sequencing may be useful for neonates with unexplained early liver failure if extensive genetic and metabolic testing is inconclusive.
Assuntos
Doenças do Prematuro/genética , Leucina-tRNA Ligase/genética , Falência Hepática/genética , Anormalidades Musculoesqueléticas/genética , Mutação de Sentido Incorreto , Mutação Puntual , Sítios de Splice de RNA/genética , Substituição de Aminoácidos , Anemia Neonatal/genética , Éxons/genética , Evolução Fatal , Retardo do Crescimento Fetal/genética , Genes Recessivos , Heterozigoto , Humanos , Hiperbilirrubinemia Neonatal/genética , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/patologia , Íntrons/genética , Leucina-tRNA Ligase/deficiência , Cirrose Hepática/etiologia , Falência Hepática/patologia , Falência Hepática Aguda/etiologia , Falência Hepática Aguda/patologia , Masculino , Insuficiência de Múltiplos Órgãos/etiologia , Músculo Esquelético/patologia , Anormalidades Musculoesqueléticas/patologia , Alinhamento de Sequência , Síndrome , Sequenciamento do ExomaRESUMO
BACKGROUND: Wolcott-Rallison Syndrome (WRS) is a rare autosomal recessive disease that is the most common cause of neonatal diabetes in consanguineous families. WRS is caused by various genetic alterations of the Eukaryotic Translation Initiation Factor 2-Alpha Kinase 3 (EIF2AK3) gene. METHODS: Genetic analysis of a consanguineous family where two children were diagnosed with WRS was performed by Sanger sequencing. The altered protein was investigated by in vitro cloning, expression and immunohistochemistry. RESULTS: The first cases in Hungary, - two patients in one family, where the parents were fourth-degree cousins - showed the typical clinical features of WRS: early onset diabetes mellitus with hyperglycemia, growth retardation, infection-induced multiple organ failure. The genetic background of the disease was a novel alteration in the EIF2AK3 gene involving the splice site of exon 11- intron 11-12 boundary: g.53051_53062delinsTG. According to cDNA sequencing this created a new splice site and resulted in a frameshift and the development of an early termination codon at amino acid position 633 (p.Pro627AspfsTer7). Based on in vitro cloning and expression studies, the truncated protein was functionally inactive. Immunohistochemistry revealed that the intact protein was absent in the islets of pancreas, furthermore insulin expressing cells were also dramatically diminished. Elevated GRP78 and reduced CHOP protein expression were observed in the liver. CONCLUSIONS: The novel genetic alteration causing the absence of the EIF2AK3 protein resulted in insufficient handling of severe endoplasmic reticulum stress, leading to liver failure and demise of the patients.
Assuntos
Diabetes Mellitus Tipo 1/genética , Epífises/anormalidades , Mutação INDEL , Osteocondrodisplasias/genética , Sítios de Splice de RNA/genética , eIF-2 Quinase/genética , Pré-Escolar , Consanguinidade , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/patologia , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/genética , Epífises/patologia , Evolução Fatal , Feminino , Mutação da Fase de Leitura , Humanos , Hungria , Lactente , Falência Hepática/complicações , Falência Hepática/genética , Falência Hepática/patologia , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/patologia , Linhagem , Irmãos , Viroses/complicações , Viroses/patologiaAssuntos
Citrulinemia/diagnóstico , Falência Hepática/etiologia , Aminoácidos/sangue , Proteínas de Ligação ao Cálcio/metabolismo , Citrulinemia/complicações , Citrulinemia/dietoterapia , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Falência Hepática/genética , Masculino , Transportadores de Ânions Orgânicos/metabolismo , Irmãos , Tirosinemias/diagnósticoRESUMO
During viral infections viruses express molecules that interfere with the host-cell death machinery and thus inhibit cell death responses. For example the viral FLIP (vFLIP) encoded by Kaposi's sarcoma-associated herpesvirus interacts and inhibits the central cell death effector, Caspase-8. In order to analyze the impact of anti-apoptotic viral proteins, like vFlip, on liver physiology in vivo, mice expressing vFlip constitutively in hepatocytes (vFlipAlbCre+) were generated. Transgenic expression of vFlip caused severe liver tissue injury accompanied by massive hepatocellular necrosis and inflammation that finally culminated in early postnatal death of mice. On a molecular level, hepatocellular death was mediated by RIPK1-MLKL necroptosis driven by an autocrine TNF production. The loss of hepatocytes was accompanied by impaired bile acid production and disruption of the bile duct structure with impact on the liver-gut axis. Notably, embryonic development and tissue homeostasis were unaffected by vFlip expression. In summary our data uncovered that transgenic expression of vFlip can cause severe liver injury in mice, culminating in multiple organ insufficiency and death. These results demonstrate that viral cell death regulatory molecules exhibit different facets of activities beyond the inhibition of cell death that may merit more sophisticated in vitro and in vivo analysis.
Assuntos
Hepatócitos/metabolismo , Hepatócitos/patologia , Falência Hepática/metabolismo , Proteínas Virais/biossíntese , Animais , Morte Celular/fisiologia , Infecções por Herpesviridae/metabolismo , Infecções por Herpesviridae/patologia , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/metabolismo , Humanos , Falência Hepática/genética , Falência Hepática/patologia , Camundongos , Camundongos Transgênicos , Necrose , Transdução de Sinais , Proteínas Virais/genéticaRESUMO
BACKGROUND: PNPLA3 rs738409 minor allele c.444G represents a risk factor for liver steatosis and fibrosis progression also in chronic hepatitis C (HCV). We investigated its impact on the timing of liver transplantation (LT) in patients with genotype 1b HCV cirrhosis. METHODS: We genotyped and evaluated 172 LT candidates with liver cirrhosis owing to chronic HCV infection, genotype 1b. One hundred patients needed LT for chronic liver failure (CLF) and 72 for a small hepatocellular carcinoma (HCC) in the cirrhotic liver without CLF. Population controls (n = 647) were selected from the Czech cross-sectional study MONICA. RESULTS: The CLF patients were younger (53.5 ± 7.2 vs. 59.6 ± 6.6, P < 0.001) with more advanced liver disease than HCC patients (Child-Pugh's score 9.1 ± 1.8 vs. 7.1 ± 1.9, P < 0.001, MELD 14.1 ± 3.9 vs. 11.1 ± 3.7, P < 0.001). PNPLA3 G allele increased the risk of LT for CLF in both allelic and recessive models (CG + GG vs. CC: OR, 1.90; 95% CI, 1.017-3.472, P = 0.045 and GG vs. CC + CG: OR, 2.94; 95% CI, 1.032-7.513, P = 0.042). Multivariate analysis identified younger age (P < 0.001) and the G allele (P < 0.05) as risk factors for CLF. The genotype frequencies between the CLF group and MONICA study significantly differed in both, allelic and recessive model (P = 0.004, OR 1.87, 95% CI 1.222-2.875; P < 0.001, OR 3.33, 95% CI 1.824-6.084, respectively). The OR values almost doubled in the recessive model compared with the allelic model suggesting the additive effect of allele G. In contrast, genotype frequencies in the HCC group were similar to the MONICA study in both models. Pretransplant viral load was significantly lower in GG than in CC + CG genotypes (median, IQR; 162,500 (61,550-319,000) IU/ml vs. 570,000 (172,000-1,595,000) IU/ml, P < 0.0009). CONCLUSIONS: Our results suggest that PNPLA3 rs738409 G allele carriage may be associated with a faster progression of HCV cirrhosis to chronic liver failure.
Assuntos
Predisposição Genética para Doença/genética , Hepatite C Crônica/genética , Hepatite C Crônica/virologia , Lipase/genética , Cirrose Hepática/genética , Falência Hepática/genética , Proteínas de Membrana/genética , Polimorfismo de Nucleotídeo Único/genética , Alelos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Estudos de Casos e Controles , Estudos Transversais , Feminino , Genótipo , Humanos , Fígado/virologia , Cirrose Hepática/virologia , Falência Hepática/virologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Transplante de Fígado/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Carga Viral/métodosRESUMO
BACKGROUND Matricellular proteins of the extracellular matrix (ECM) include tenascin-C (TNC) and cellular communication network factor 3 (CCN3). This study aimed to investigate the role of TNC and CCN3 as prognostic factors for post hepatectomy liver failure (PHLF) in a rat model of partial hepatectomy and 50 patients following partial hepatectomy. MATERIAL AND METHODS Sprague-Dawley rats underwent 85% (n=53) or 90% hepatectomy (n=53) in the partial hepatectomy (PHx) model. TNC and CCN3 mRNA expression in residual liver tissue was evaluated using quantitative reverse transcription-polymerase chain reaction (qRT-PCR), and enzyme-linked immunoassay (ELISA) determined the serum levels of TNC and CCN3. In 50 patients who underwent partial hepatectomy, TNC and CCN3 serum levels were measured on postoperative day 1 and day 3. RESULTS In the rat partial hepatectomy model, mRNA and serum levels of TNC and CCN3 were significantly increased within the first 24 h, and were higher in the 90% PHx group compared with the 85% PHx group. Fifty patients who underwent partial hepatectomy, included patients with PHLF (n=12) and patients without PHLF (n=38). Multivariate analysis confirmed that serum levels on postoperative day 3 TNChigh+CCN3high was a significant predictor of PHLF, which was associated with more than twice the risk of severe morbidity when compared with the low-risk patients (80% vs. 30%) and a significantly longer hospital stay (17 days vs. 8 days). CONCLUSIONS Further studies are needed to evaluate the potential role of the matricellular proteins, TNC and CCN3 as early clinical predictors for PHLF.
Assuntos
Hepatectomia/efeitos adversos , Falência Hepática/etiologia , Proteína Sobre-Expressa em Nefroblastoma/metabolismo , Tenascina/metabolismo , Adulto , Idoso , Animais , Área Sob a Curva , Bilirrubina/sangue , Modelos Animais de Doenças , Feminino , Humanos , Tempo de Internação , Falência Hepática/sangue , Falência Hepática/genética , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Morbidade , Análise Multivariada , Proteína Sobre-Expressa em Nefroblastoma/sangue , Proteína Sobre-Expressa em Nefroblastoma/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Curva ROC , Ratos Sprague-Dawley , Fatores de Risco , Análise de Sobrevida , Tenascina/sangue , Tenascina/genéticaRESUMO
Posthepatectomy liver failure (PHLF) may occur after extended partial hepatectomy (PH). If malignancy is widespread in the liver, the size of PH and hence the size of the future liver remnant (FLR) may limit curability. We aimed to characterize differences in protein expression between different sizes of FLRs and identify proteins specific to the regenerative process of minimal-size FLR (MSFLR), with special focus on postoperative day (POD) 1 when PHLF is present. A total of 104 male Wistar rats were subjected to 30, 70, or 90% PH (MSFLR in rats), sham operation, or no operation. Blood and liver tissue were harvested at POD1, 3, and 5 (n = 8 per group). Protein expression was assessed by proteomic profiling by unsupervised two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) liquid chromatography tandem mass spectrometry (LC-MS/MS), followed by supervised selected reaction monitoring (SRM)-MS/MS. In all, 1,035 protein spots were detected, 54 of which were significantly differentially expressed between groups and identifiable. During PHLF after PH(90%) at POD1, urea cycle and related proteins showed significant perturbations, including the urea cycle flux-regulating enzyme of carbamoyl phosphate synthase-1, ornithine transcarbamylase, and arginase-1, as well as the ornithine aminotransferase and propionyl-CoA carboxylase alpha chain. Plasma-ammonia increased significantly at POD1 after PH(90%), followed by a prompt decrease. At the protein level, we found perturbations of urea cycle and related enzymes in the MSFLR during PHLF. Our results suggest that these perturbations may augment urea cycle function, which may be pivotal for increased ammonia elimination after extensive PHs and potential PHLF.NEW & NOTEWORTHY Posthepatectomy liver failure (PHLF) is associated with high mortality. In a rat model of 90% hepatectomy, PHLF is present. Our results on liver tissue proteomics suggest that the ability of the liver remnant to sufficiently eliminate ammonia may be brought about by perturbation related to urea cycle proteins and that enhancing the urea cycle capacity may play a key role in surviving PHLF.
Assuntos
Hepatectomia , Falência Hepática/metabolismo , Distúrbios Congênitos do Ciclo da Ureia/metabolismo , Amônia/sangue , Animais , Biologia Computacional , Expressão Gênica , Falência Hepática/genética , Masculino , Biossíntese de Proteínas , Proteômica , RNA Mensageiro/biossíntese , Ratos , Ratos Wistar , Distúrbios Congênitos do Ciclo da Ureia/genéticaAssuntos
Predisposição Genética para Doença , Encefalopatia Hepática/genética , Falência Hepática/genética , Falência Hepática/patologia , Proteínas de Membrana/genética , Proteínas Mitocondriais/genética , Biópsia por Agulha , Causas de Morte , Progressão da Doença , Feminino , Humanos , Imuno-Histoquímica , Lactente , Recém-Nascido , Expectativa de Vida , Testes de Função Hepática , Linhagem , Fenótipo , Medição de Risco , Taxa de Sobrevida , Gêmeos MonozigóticosRESUMO
Fibroblasts of a patient with Infantile Liver Failure Syndrome 2 (OMIM #616483) due to a homozygous missense variant in the neuroblastoma amplified sequence gene (NBAS; c.[2708T>G]; c.[2708T>G]/p.[Leu903Arg]; p.[Leu903Arg]) were reprogrammed to iPSCs using the Cytotune®-iPS 2.0 Sendai Reprogramming Kit (Invitrogen) delivering the reprogramming factors Oct3/4, Sox2, c-Myc and Klf4. Cells showed a normal karyotype. Pluripotency of DHMCi004-A was proven using immunohistochemistry, RT-PCR analysis, flow cytometry and differentiation into all three germ layers using the STEMdiff™ Trilineage Differentiation Kit (Stemcell Technologies). DHMCi004-A represents the first iPS-based cell model system to elucidate the pathomechanism underlying this disease.
Assuntos
Linhagem Celular , Doenças Genéticas Inatas , Células-Tronco Pluripotentes Induzidas , Falência Hepática , Mutação de Sentido Incorreto , Proteínas de Neoplasias , Pré-Escolar , Feminino , Doenças Genéticas Inatas/genética , Doenças Genéticas Inatas/metabolismo , Doenças Genéticas Inatas/patologia , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Fator 4 Semelhante a Kruppel , Falência Hepática/genética , Falência Hepática/patologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , SíndromeRESUMO
Despite judicious monitoring and care, patients with fatty acid oxidation disorders may experience metabolic decompensation due to infection which may result in rhabdomyolysis, cardiomyopathy, hypoglycemia and liver dysfunction and failure. Since clinical studies on metabolic decompensation are dangerous, we employed a preclinical model of metabolic decompensation due to infection. By infecting mice with mouse adapted influenza and using a pair-feeding strategy in a mouse model of long-chain fatty acid oxidation (Acadvl-/-), our goals were to isolate the effects of infection on tissue acylcarnitines and determine how they relate to their plasma counterparts. Applying statistical data reduction techniques (Partial Least Squares-Discriminant Analysis), we were able to identify critical acylcarnitines that were driving differentiation of our experimental groups for all the tissues studied. While plasma displayed increases in metabolites directly related to mouse VLCAD deficiency (e.g. C16 and C18), organs like the heart, muscle and liver also showed involvement of alternative pathways (e.g. medium-chain FAO and ketogenesis), suggesting adaptive measures. Matched correlation analyses showed strong correlations (râ¯>â¯0.7) between plasma and tissue levels for a small number of metabolites. Overall, our results demonstrate that infection as a stress produces perturbations in metabolism in Acadvl-/- that differ greatly from WT infected and Acadvl-/- pair-fed controls. This model system will be useful for studying the effects of infection on tissue metabolism as well as evaluating interventions aimed at modulating the effects of metabolic decompensation.
Assuntos
Acil-CoA Desidrogenase de Cadeia Longa/deficiência , Carnitina/análogos & derivados , Ácidos Graxos/metabolismo , Erros Inatos do Metabolismo Lipídico/genética , Doenças Metabólicas/genética , Doenças Mitocondriais/genética , Doenças Musculares/genética , Acil-CoA Desidrogenase de Cadeia Longa/genética , Animais , Cardiomiopatias/genética , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Carnitina/metabolismo , Síndrome Congênita de Insuficiência da Medula Óssea , Modelos Animais de Doenças , Feminino , Humanos , Hipoglicemia/genética , Hipoglicemia/metabolismo , Hipoglicemia/patologia , Peroxidação de Lipídeos/genética , Fígado/metabolismo , Fígado/fisiologia , Falência Hepática/genética , Falência Hepática/metabolismo , Falência Hepática/patologia , Doenças Metabólicas/metabolismo , Doenças Metabólicas/patologia , Camundongos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Miocárdio/patologia , OxirreduçãoRESUMO
Mice that are deficient in superoxide dismutase 1 (Sod1), an antioxidative enzyme, are susceptible to developing liver steatosis. Peroxiredoxin 4 (Prdx4) catalyzes disulfide bond formation in proteins via the action of hydrogen peroxide and hence decreases oxidative stress and supports oxidative protein folding for the secretion of lipoproteins. Because elevated reactive oxygen species induce endoplasmic reticulum stress, this negative chain reaction is likely involved in the development of nonalcoholic fatty liver diseases and more advanced steatohepatitis (NASH). In the current study, we generated Prdx4 and Sod1 double knockout (DKO; Prdx4-/ySod1-/-) mice and examined whether the combined deletion of Prdx4 and Sod1 aggravated liver pathology compared to single knockout and wild-type mice. The secretion of triglyceride-rich lipoprotein was strikingly impaired in the DKO mice, leading to aggravated liver steatosis. Simultaneously, the activation of caspase-3 in the liver was observed. The hyperoxidation of Prdxs, a hallmark of oxidative stress, occurred in different isoforms that are uniquely associated with Sod1-/- and Prdx4-/y mice, and the effect was additive in DKO mouse livers. Because DKO mice spontaneously develop severe liver failure at a relatively young stage, they have the potential for use as a model for hepatic disorders and for testing other potential treatments.
Assuntos
Falência Hepática/metabolismo , Fígado/metabolismo , Peroxirredoxinas/metabolismo , Superóxido Dismutase-1/metabolismo , Animais , Western Blotting , Células Cultivadas , Feminino , Glutationa/metabolismo , Fígado/patologia , Falência Hepática/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Estresse Oxidativo/genética , Estresse Oxidativo/fisiologia , Peroxirredoxinas/genética , Superóxido Dismutase-1/genéticaRESUMO
Acute liver injury (ALI) is characterized by hepatocyte damage and inflammation. In the present study, we examined whether the absence of Sprouty-related EVH1-domain-containing protein 2 (Spred2), a negative regulator of the Ras/Raf/ERK/MAPK pathway, influences ALI induced by D-galactosamine (D-GalN) and lipopolysaccharide (LPS). Compared to wild-type mice, Spred2-/- mice developed exacerbated liver injury represented by enhanced hepatocyte damage and inflammation. Enhanced ERK activation was observed in Spred2-/--livers, and the MEK/ERK inhibitor U0126 ameliorated ALI. Hepatic tumour necrosis factor α (TNFα) and interleukin (IL)-1ß levels were increased in Spred-2-/--livers, and the neutralization of TNFα dramatically ameliorated ALI, which was associated with decreased levels of endogenous TNFα and IL-1ß. When mice were challenged with D-GalN and TNFα, much severer ALI was observed in Spred2-/- mice with significant increases in endogenous TNFα and IL-1ß in the livers. Immunohistochemically, Kupffer cells were found to produce TNFα, and isolated Kupffer cells from Spred2-/- mice produced significantly higher levels of TNFα than those from wild-type mice after LPS stimulation, which was significantly decreased by U0126. These results suggest that Spred2 negatively regulates D-GalN/LPS-induced ALI under the control of TNFα in Kupffer cells. Spred2 may present a therapeutic target for the treatment of ALI.
Assuntos
Falência Hepática/metabolismo , Proteínas Repressoras/genética , Animais , Células Cultivadas , Galactosamina/toxicidade , Hepatócitos/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Células de Kupffer/metabolismo , Lipopolissacarídeos/toxicidade , Falência Hepática/etiologia , Falência Hepática/genética , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Repressoras/deficiência , Proteínas Repressoras/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Neuroblastoma amplified sequence (NBAS) gene mutation or infantile liver failure syndrome type 2 (ILFS type 2) is an extremely rare disease characterized by episodic liver failure precipitated by intercurrent febrile illness, and liver function recovering completely. Here, we report a 4-year-old girl with recurrent hepatitis. A diagnosis of ILFS type 2 was made based on NBAS mutation gene found by whole-exome sequencing. Our case provides a new insight toward considering NBAS mutation as a part of the differential diagnoses of any infant presenting with recurrent liver failure or hepatitis. We recommend sequencing NBAS in cases of recurrent hepatitis in infancy of unknown cause, especially in individuals with fever-associated hepatic dysfunction.
Assuntos
Hepatite/diagnóstico , Hepatite/genética , Falência Hepática/diagnóstico , Falência Hepática/genética , Mutação , Proteínas de Neoplasias/genética , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Falência Hepática/patologia , Proteínas de Neoplasias/deficiência , Doenças Raras , Recidiva , Sequenciamento do Exoma/métodosRESUMO
Liver failure is a severe clinical syndrome with a poor prognosis. Mesenchymal stem cell (MSC) transplantation has emerged as a new intervention in treating liver failure. It is conventionally recognized that MSCs exert their therapeutic effect mainly through transdifferentiation. Recently, published articles have shown that MSCs work in liver failure by secreting trophic and immunomodulatory factors as well as extracellular vesicles (EVs) before transdifferentiation. In particular,MSC-derived EVs have shown similar curative effects as MSCs. Here we review the role of MSCs as well as their derived factors and EVs in liver failure and discuss the use of MSC-derived EVs instead of intact MSCs in treating liver failure.
Assuntos
Falência Hepática/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Células da Medula Óssea/metabolismo , Proliferação de Células/genética , Transdiferenciação Celular/genética , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Humanos , Falência Hepática/genética , Falência Hepática/patologiaRESUMO
The liver and kidney functions of recipients of liver transplantation (LT) surgery with heart beating (HBD, n = 13) or living donors (LD, n = 9) with different cold ischemia times were examined during the neohepatic phase for the elimination of rocuronium bromide (ROC, cleared by liver and kidney) and tranexamic acid (TXA, cleared by kidney). Solid phase micro-extraction and LC-MS/MS was applied to determine the plasma concentrations of ROC and TXA, and creatinine was determined by standard laboratory methods. Metabolomics and the relative expressions of miR-122, miR-148a and γ-glutamyltranspeptidase (GGT), liver injury biomarkers, were also measured. The ROC clearance for HBD was significantly lower than that for LD (0.147 ± 0.052 vs. 0.265 ± 0.148 ml·min-1 ·g-1 liver) after intravenous injection (0.6 mg·kg-1 ). The clearance of TXA, a compound cleared by glomerular filtration, given as a 1 g bolus followed by infusion (10 mg·kg-1 ·h-1 ), was similar between HBD and LD groups (~ 1 ml·min-1 ·kg-1 ). The TXA clearance in both groups was lower than the GFR, showing a small extent of hepatorenal coupling. The miR-122 and miR-148a expressions were similar for the HBD and LD groups, whereas GGT expression was significantly increased for HBD. The lower ROC clearance and the higher GGT levels in the HBD group of longer cold ischemia times performed worse than the LD group during the neophase. Metabololmics further showed clusters of bile acids, phospholipids and lipid ω-oxidation products for the LD and HBD groups. In conclusion, ROC CL and GGT expression, and metabolomics could serve as sensitive indices of early graft function. Copyright © 2017 John Wiley & Sons, Ltd.
Assuntos
Falência Hepática , Transplante de Fígado , Doadores de Tecidos , Adulto , Idoso , Androstanóis/sangue , Androstanóis/farmacocinética , Biomarcadores/análise , Feminino , Humanos , Falência Hepática/genética , Falência Hepática/metabolismo , Masculino , Metabolômica , MicroRNAs/genética , Pessoa de Meia-Idade , Modelos Biológicos , Projetos Piloto , Rocurônio , Ácido Tranexâmico/sangue , Ácido Tranexâmico/farmacocinética , gama-Glutamiltransferase/genéticaRESUMO
Generating functional hepatocyte-like cells (HLCs) from mesenchymal stem cells (MSCs) is of great urgency for bio-artificial liver support system (BALSS). Previously, we obtained HLCs from human umbilical cord-derived MSCs by overexpressing seven microRNAs (HLC-7) and characterized their liver functions in vitro and in vivo. Here, we aimed to screen out the optimal miRNA candidates for hepatic differentiation. We sequentially removed individual miRNAs from the pool and examined the effect of transfection with remainder using RT-PCR, periodic acid-Schiff (PAS) staining and low-density lipoprotein (LDL) uptake assays and by assessing their function in liver injury models. Surprisingly, miR-30a and miR-1290 were dispensable for hepatic differentiation. The remaining five miRNAs (miR-122, miR-148a, miR-424, miR-542-5p and miR-1246) are essential for this process, because omitting any one from the five-miRNA combination prevented hepatic trans-differentiation. We found that HLCs trans-differentiated from five microRNAs (HLC-5) expressed high level of hepatic markers and functioned similar to hepatocytes. Intravenous transplantation of HLC-5 into nude mice with CCl4 -induced fulminant liver failure and acute liver injury not only improved serum parameters and their liver histology, but also improved survival rate of mice in severe hepatic failure. These data indicated that HLC-5 functioned similar to HLC-7 in vitro and in vivo, which have been shown to resemble hepatocytes. Instead of using seven-miRNA combination, a simplified five-miRNA combination can be used to obtain functional HLCs in only 7 days. Our study demonstrated an optimized and efficient method for generating functional MSC-derived HLCs that may serve as an attractive cell alternative for BALSS.