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1.
Gut ; 69(2): 355-364, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-30979717

RESUMO

OBJECTIVES: Polyploidy is a fascinating characteristic of liver parenchyma. Hepatocyte polyploidy depends on the DNA content of each nucleus (nuclear ploidy) and the number of nuclei per cell (cellular ploidy). Which role can be assigned to polyploidy during human hepatocellular carcinoma (HCC) development is still an open question. Here, we investigated whether a specific ploidy spectrum is associated with clinical and molecular features of HCC. DESIGN: Ploidy spectra were determined on surgically resected tissues from patients with HCC as well as healthy control tissues. To define ploidy profiles, a quantitative and qualitative in situ imaging approach was used on paraffin tissue liver sections. RESULTS: We first demonstrated that polyploid hepatocytes are the major components of human liver parenchyma, polyploidy being mainly cellular (binuclear hepatocytes). Across liver lobules, polyploid hepatocytes do not exhibit a specific zonation pattern. During liver tumorigenesis, cellular ploidy is drastically reduced; binuclear polyploid hepatocytes are barely present in HCC tumours. Remarkably, nuclear ploidy is specifically amplified in HCC tumours. In fact, nuclear ploidy is amplified in HCCs harbouring a low degree of differentiation and TP53 mutations. Finally, our results demonstrated that highly polyploid tumours are associated with a poor prognosis. CONCLUSIONS: Our results underline the importance of quantification of cellular and nuclear ploidy spectra during HCC tumorigenesis.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Poliploidia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Estudos de Casos e Controles , Diferenciação Celular/genética , Núcleo Celular/patologia , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Feminino , Hepatócitos/patologia , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
2.
Toxicol Lett ; 321: 114-121, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31830554

RESUMO

Despite numerous studies on the toxicities of planar polycyclic aromatic hydrocarbons (PAHs), very little is known about the toxicological profiles of non-planar PAHs. In the present study, the cytotoxicity of corannulene (COR), a typical bowl-shaped PAH with a myriad of applications in the area of material chemistry, and benzo[a]pyrene (BaP), a typical planar PAH with similar molecular weight, were systematically compared in various cell lines. Compared with BaP, exposure to COR resulted in less cytotoxic responses in both human (HepG2) and murine (Hepa1-6) hepatoma cells, which was characterized with a slower cellular accumulation as well as a weaker induction of cytochrome P450 1 (CYP1/Cyp1) isozymes. Knockdown of aryl hydrocarbon receptor (AhR) by siRNA attenuated the inductive effect of COR on CYP1A/Cyp1a mRNA levels in these two cell lines. Further analysis revealed that derivatization greatly influenced the cytotoxicity of COR, which was positively correlated with their binding affinities to the AhR, as demonstrated by in silico molecular docking. Overall, these results suggest that AhR appears to be involved in the cytotoxic responses of COR and its derivatives, providing a fundamental understanding of the biological effects of bowl-like PAHs.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/agonistas , Hepatócitos/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Receptores de Hidrocarboneto Arílico/agonistas , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Sítios de Ligação , Citocromo P-450 CYP1A1/biossíntese , Citocromo P-450 CYP1A1/genética , Indução Enzimática , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Camundongos , Simulação de Acoplamento Molecular , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Ligação Proteica , Conformação Proteica , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais , Relação Estrutura-Atividade
3.
Gut ; 69(1): 133-145, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31409605

RESUMO

OBJECTIVE: The Fragile X mental retardation (FMR) syndrome is a frequently inherited intellectual disability caused by decreased or absent expression of the FMR protein (FMRP). Lack of FMRP is associated with neuronal degradation and cognitive dysfunction but its role outside the central nervous system is insufficiently studied. Here, we identify a role of FMRP in liver disease. DESIGN: Mice lacking Fmr1 gene expression were used to study the role of FMRP during tumour necrosis factor (TNF)-induced liver damage in disease model systems. Liver damage and mechanistic studies were performed using real-time PCR, Western Blot, staining of tissue sections and clinical chemistry. RESULTS: Fmr1null mice exhibited increased liver damage during virus-mediated hepatitis following infection with the lymphocytic choriomeningitis virus. Exposure to TNF resulted in severe liver damage due to increased hepatocyte cell death. Consistently, we found increased caspase-8 and caspase-3 activation following TNF stimulation. Furthermore, we demonstrate FMRP to be critically important for regulating key molecules in TNF receptor 1 (TNFR1)-dependent apoptosis and necroptosis including CYLD, c-FLIPS and JNK, which contribute to prolonged RIPK1 expression. Accordingly, the RIPK1 inhibitor Necrostatin-1s could reduce liver cell death and alleviate liver damage in Fmr1null mice following TNF exposure. Consistently, FMRP-deficient mice developed increased pathology during acute cholestasis following bile duct ligation, which coincided with increased hepatic expression of RIPK1, RIPK3 and phosphorylation of MLKL. CONCLUSIONS: We show that FMRP plays a central role in the inhibition of TNF-mediated cell death during infection and liver disease.


Assuntos
Proteína do X Frágil de Retardo Mental/fisiologia , Hepatite Viral Animal/imunologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Infecções por Arenaviridae/imunologia , Infecções por Arenaviridae/patologia , Linfócitos T CD8-Positivos/imunologia , Morte Celular/efeitos dos fármacos , Morte Celular/imunologia , Morte Celular/fisiologia , Células Cultivadas , Colestase/imunologia , Colestase/metabolismo , Colestase/patologia , Proteína do X Frágil de Retardo Mental/metabolismo , Hepatite Viral Animal/patologia , Hepatite Viral Animal/prevenção & controle , Hepatócitos/patologia , Imidazóis/farmacologia , Imidazóis/uso terapêutico , Indóis/farmacologia , Indóis/uso terapêutico , Vírus da Coriomeningite Linfocítica , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Serina-Treonina Quinases de Interação com Receptores/antagonistas & inibidores , Proteína Serina-Treonina Quinases de Interação com Receptores/fisiologia
4.
Toxicol Lett ; 318: 74-85, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31654802

RESUMO

Metabolic flexibility defines the capacity of cells to respond to changes in nutrient status. Mitochondria are important mediators of metabolic flexibility and dysfunction is associated with metabolic inflexibility and pathology. Foodborne toxins are often overlooked as potential factors contributing to metabolic toxicity. Fusaric acid (FA), a neglected mycotoxin, is known to disrupt mitochondrial function. The aim of this study was to investigate the molecular mechanisms underlying a metabolic switch in response to FA. This study investigated the effects of FA on energy homeostasis in cultured human liver (HepG2) cells. HepG2 cells poised to undergo oxidative and glycolytic metabolism were exposed to a range of FA concentrations (4, 63 and 250 µg/mL) for 6 h. We determined mitochondrial toxicity, acetyl CoA levels and cell viability using luminometric, fluorometric and spectrophotometric methods. Expression of metabolic proteins (PDK1, PKM2, phosphorylated-PDH E1α and HIF-1α) and mRNAs (HIF-1α, PKM2, LDHa and PDK1) were determined using western blot and qPCR respectively. Our data connects a constitutive expression of HIF-1α in response to FA, to the inhibition of pyruvate decarboxylation through up-regulation of PDK-1 and phosphorylation of Pyruvate Dehydrogenase E1α subunit. Moreover, we highlight the potential of FA to induce a glucose "addiction" and phenotype reminiscent of the Warburg effect. The findings provide novel insights into the impact of this neglected foodborne mycotoxin in the dysregulation of energy metabolism.


Assuntos
Plasticidade Celular/efeitos dos fármacos , Microbiologia de Alimentos , Ácido Fusárico/toxicidade , Glicólise/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/patologia , Fenótipo , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Piruvato Desidrogenase (Lipoamida)/metabolismo
5.
Toxicol Lett ; 321: 69-72, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31863871

RESUMO

The molecular toxicology of the chemical warfare agent sulfur mustard (SM) is still not completely understood. It has been suggested that in addition to SM itself also biotransformation products thereof mediate cytotoxicity. In the current study, we assessed this aspect by exposing a human hepatocyte cell line (HepG2) to SM or to its oxidation products sulfur mustard sulfoxide (SMO), sulfur mustard sulfone (SMO2), and divinyl sulfone (DVS). Cytotoxicity, determined with the XTT assay, revealed a significant higher toxicity of SMO2 and DVS compared to SM while SMO had no effect at any concentration. The exact biotransformation of SM leading to SMO, SMO2 and finally DVS is unknown so far. Involvement of the CYP450 system is discussed and was also investigated in the presented study. Modulation of CYP1A2 activity, taken as a model enzyme for CYP450, affected cytotoxicity of SM, SMO2 or DVS significantly. Induction of CYP1A2 with omeprazole led to decreased cytotoxicity for all compounds whereas inhibition with cimetidine resulted in an increased cytotoxicity for SM, but not for SMO2 and DVS. Our results indicate a distinctive role of the CYP450 system in SM poisoning. Future studies should address the metabolic conversion of SM in more detail. Our data may suggest the well-tolerated drug omeprazole as a potential co-treatment after contact to SM.


Assuntos
Hepatócitos/efeitos dos fármacos , Gás de Mostarda/toxicidade , Agentes Neurotóxicos/toxicidade , Sulfonas/toxicidade , Sulfóxidos/toxicidade , Antídotos/farmacologia , Cimetidina/farmacologia , Citocromo P-450 CYP1A2/biossíntese , Indutores do Citocromo P-450 CYP1A2/farmacologia , Inibidores do Citocromo P-450 CYP1A2/farmacologia , Relação Dose-Resposta a Droga , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Gás de Mostarda/metabolismo , Agentes Neurotóxicos/metabolismo , Omeprazol/farmacologia , Oxirredução , Sulfonas/metabolismo , Sulfóxidos/metabolismo
6.
Toxicol Lett ; 321: 131-137, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31877331

RESUMO

Prior exposures to chemicals/agents may alter epigenome in such a way that subsequent exposure to the same or different xenobiotic would produce different responses. Understanding the mechanism for this "priming" effect is of clinical significance in avoiding adverse drug-drug interactions. Here we reported a dramatic priming effect of dimethyl sulfoxide (DMSO) on pregnane X receptor (PXR)-mediated gene regulations and analyzed the underpinning epigenetic mechanism. We showed that DMSO (1.25-2.5 %) pretreatment has a profound effect in enhancing the expression of PXR target genes. This priming effect persisted up to 48 h. Mechanistically, DMSO pretreatment reduced H4K12 acetylation and therefore enhanced the subsequent rifampicin stimulated histone H4R3 methylation on the regulatory region of PXR target gene CYP3A4. We showed that protein arginine methyltransferase 1 (PRMT1), which methylates H4R3, was important for priming by DMSO. Inhibition of methyltransferase by the pharmacological inhibitor adenosine dialehyde (AdoX), or RNAi knockdown of PRMT1, abolished the DMSO priming effects. On the other hand, Trichostation A (TSA) pretreatment, which increases histone acetylation and therefore suppresses H4R3 methylation, also abolished the DMSO priming effects. Based on the above observation, we proposed a model of sequential order of histone methylation and acetylation on the transcription "relay".


Assuntos
Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Dimetil Sulfóxido/toxicidade , Epigênese Genética/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Histonas/metabolismo , Receptor de Pregnano X/agonistas , Acetilação , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Metilação , Receptor de Pregnano X/genética , Receptor de Pregnano X/metabolismo , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Tempo
7.
Life Sci ; 239: 117010, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31672578

RESUMO

AIMS: Amlexanox, an inhibitor of nuclear factor κB kinase epsilon (IKKε) and TANK-binding kinase 1(TBK1), was demonstrated to be effective in diabetes and obesity. The aim of this study was to explore the molecular mechanisms of its role in non-alcoholic fatty liver disease (NAFLD). MAIN METHODS: NAFLD mouse models were established by using eight-week-old male C57BL/6 mice fed with high-fat diet (HFD) or (and) lipopolysaccharide (LPS) for 18 weeks. From the beginning of HFD, HFD-induced mice were subjected to amlexanox or vehicle for 18 weeks. HFD + LPS-induced mice were treated with amlexanox or vehicle for the last 6 weeks. Blood biochemistry parameters were determined using automatic biochemistry analyzer. Histological changes of liver tissue were observed by hematoxylin-eosin (H&E) staining and Oil Red O staining. The expressions of IKKε and smooth muscle actin-α (α-SMA) were evaluated through immunohistochemistry. Serum inflammatory mediator was determined by enzyme linked immunosorbent assay (ELISA). Gene expressions involved in glucose and lipid metabolism, insulin signaling pathway were examined using quantitative RT-PCR or Western blotting. KEY FINDINGS: This study demonstrated that amlexanox reversed glucose and lipid metabolic disturbance and hepatic steatosis in NAFLD mice model. IKKε was specific expressed in hepatic stellate cells (HSCs) instead of hepatocytes. This study also found that amlexanox improved insulin signaling (Insulin-IRS-1-Akt) in hepatocytes through inhibiting inflammation (IKKε-NF-κB-TNF-α/IL-1α) in HSCs. SIGNIFICANCE: The present study confirmed that IKKε was specific expressed in HSCs. Inhibition of activated HSCs was responsible for effects of amlexanox on NAFLD, with improving insulin signal pathway in hepatocytes.


Assuntos
Aminopiridinas/uso terapêutico , Células Estreladas do Fígado/efeitos dos fármacos , Quinase I-kappa B/antagonistas & inibidores , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Actinas/antagonistas & inibidores , Aminopiridinas/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Insulina , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Transdução de Sinais/efeitos dos fármacos
8.
Postepy Biochem ; 65(3): 193-201, 2019 10 01.
Artigo em Polonês | MEDLINE | ID: mdl-31643166

RESUMO

Liver diseases that lead to its failure are one of the most frequent causes of death worldwide. Taking into account liver's complexity, there are no drug for acute or acute on chronic liver failure treatment. So far the only effective therapy is the liver transplantation. Unfortunately donor shortage is a main problem of this therapy. Due to this fact scientists have been looking for a new alternatives. The most promising are cell transplantation and bioartificial support systems. Without doubt hepatocytes are the best source of cells to use. But isolated human hepatocytes dedifferentiate very quickly and lose their functions ex vivo. Therefore, the new sources of cells, which could replace hepatocytes, are highly sought after. It is believed that, in order to help patients suffering from liver disease, the approach to solve this problem should be considered on different levels.


Assuntos
Doença Hepática Terminal/terapia , Hepatócitos/citologia , Hepatócitos/transplante , Fígado Artificial , Doença Hepática Terminal/patologia , Doença Hepática Terminal/fisiopatologia , Hepatócitos/patologia , Humanos
9.
Nature ; 574(7779): 538-542, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31645727

RESUMO

The most common causes of chronic liver disease are excess alcohol intake, viral hepatitis and non-alcoholic fatty liver disease, with the clinical spectrum ranging in severity from hepatic inflammation to cirrhosis, liver failure or hepatocellular carcinoma (HCC). The genome of HCC exhibits diverse mutational signatures, resulting in recurrent mutations across more than 30 cancer genes1-7. Stem cells from normal livers have a low mutational burden and limited diversity of signatures8, which suggests that the complexity of HCC arises during the progression to chronic liver disease and subsequent malignant transformation. Here, by sequencing whole genomes of 482 microdissections of 100-500 hepatocytes from 5 normal and 9 cirrhotic livers, we show that cirrhotic liver has a higher mutational burden than normal liver. Although rare in normal hepatocytes, structural variants, including chromothripsis, were prominent in cirrhosis. Driver mutations, such as point mutations and structural variants, affected 1-5% of clones. Clonal expansions of millimetres in diameter occurred in cirrhosis, with clones sequestered by the bands of fibrosis that surround regenerative nodules. Some mutational signatures were universal and equally active in both non-malignant hepatocytes and HCCs; some were substantially more active in HCCs than chronic liver disease; and others-arising from exogenous exposures-were present in a subset of patients. The activity of exogenous signatures between adjacent cirrhotic nodules varied by up to tenfold within each patient, as a result of clone-specific and microenvironmental forces. Synchronous HCCs exhibited the same mutational signatures as background cirrhotic liver, but with higher burden. Somatic mutations chronicle the exposures, toxicity, regeneration and clonal structure of liver tissue as it progresses from health to disease.


Assuntos
Células Clonais/citologia , Células Clonais/patologia , Fibrose/genética , Fibrose/patologia , Fígado/citologia , Fígado/metabolismo , Mutação , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Células Clonais/metabolismo , Análise Mutacional de DNA , Hepatócitos/citologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Filogenia , Células-Tronco/citologia , Células-Tronco/metabolismo , Células-Tronco/patologia
10.
Ecotoxicol Environ Saf ; 186: 109767, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31610358

RESUMO

Cadmium, a typical heavy metal, causes serious toxicities on many organs and tissues. As the last partially controlled class of polybrominated diphenyl ethers (PBDEs), BDE209 can also induce various health issues. Although apoptosis mediated by mitochondria has been known to be a key player in inducing toxicities by cadmium, the detailed mechanisms are incompletely understood. Moreover, co-existence of cadmium and PBDEs has been found in various environment context and human body. However, studies on the joint toxicity of cadmium and PBDEs are still limited with largely unknown mechanisms. In the present study, we investigated the adverse effects and mechanisms of single or combined treatment of CdCl2 and BDE209 on hepatocytes. We observed that apoptosis were significantly induced by CdCl2, and the combined treatment of CdCl2 and BDE209 greatly promoted the progression of apoptosis. BDE209 induced mild apoptosis. Mitochondria was the pivot of several mechanisms to induce apoptosis, including ROS production, decreased mitochondrial membrane potential (MMP), mtDNA damage and disordered calcium (Ca2+) homeostasis. However, we found that mtDNA damage and disordered Ca2+ homeostasis were the main mechanisms for CdCl2-induced apoptosis while ROS production played important roles in BDE209-induced apoptosis. Less mtDNA damage occurred in BDE209-treated cells. In the cells with combined treatment, CdCl2 and BDE209 exhibited a complementary pattern for the underlying mechanisms of apoptosis, leading to the joint toxicities, in which CdCl2 showed more contributions. In a conclusion, our results demonstrated that combined exposure to cadmium and BDE209 causes joint adverse effects on hepatocytes through diverse mechanisms as mediated by mitochondria.


Assuntos
Cádmio/toxicidade , Dano ao DNA , DNA Mitocondrial , Éteres Difenil Halogenados/toxicidade , Homeostase/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Apoptose/genética , Sinergismo Farmacológico , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Homeostase/genética , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos
11.
PLoS Pathog ; 15(9): e1007921, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31568537

RESUMO

Humans are frequently exposed to bacterial genotoxins involved in digestive cancers, colibactin and Cytolethal Distending Toxin (CDT), the latter being secreted by many pathogenic bacteria. Our aim was to evaluate the effects induced by these genotoxins on nuclear remodeling in the context of cell survival. Helicobacter infected mice, coculture experiments with CDT- and colibactin-secreting bacteria and hepatic, intestinal and gastric cells, and xenograft mouse-derived models were used to assess the nuclear remodeling in vitro and in vivo. Our results showed that CDT and colibactin induced-nuclear remodeling can be associated with the formation of deep cytoplasmic invaginations in the nucleus of giant cells. These structures, observed both in vivo and in vitro, correspond to nucleoplasmic reticulum (NR). The core of the NR was found to concentrate ribosomes, proteins involved in mRNA translation, polyadenylated RNA and the main components of the complex mCRD involved in mRNA turnover. These structures are active sites of mRNA translation, correlated with a high degree of ploidy, and involve MAPK and calcium signaling. Additional data showed that insulation and concentration of these adaptive ribonucleoprotein particles within the nucleus are dynamic, transient and protect the cell until the genotoxic stress is relieved. Bacterial genotoxins-induced NR would be a privileged gateway for selected mRNA to be preferably transported therein for local translation. These findings offer new insights into the context of NR formation, a common feature of many cancers, which not only appears in response to therapies-induced DNA damage but also earlier in response to genotoxic bacteria.


Assuntos
Toxinas Bacterianas/toxicidade , Helicobacter/patogenicidade , Ribonucleoproteínas/metabolismo , Animais , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Núcleo Celular/patologia , Sobrevivência Celular , Dano ao DNA , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/patologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Mutagênicos/toxicidade , Peptídeos/toxicidade , Policetídeos/toxicidade , RNA Mensageiro/metabolismo
12.
Pol J Pathol ; 70(2): 79-83, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31556557

RESUMO

Progressive familial intrahepatic cholestasis (PFIC) comprises a group of rare cholestatic liver disorders of childhood that could lead to liver cirrhosis. Nowadays, the partial biliary diversion procedure is still a therapeutic option in non-cirrhotic children with PFIC1 or PFIC2 after an ineffective ursodeoxycholic acid (UDCA) therapy. However, the relevant disadvantage of the partial external biliary diversion (PEBD) is that adolescent patients could not accept a permanent stoma. In some of them, despite of good clinical and biochemical results of this procedure, the ileal exclusion (IE) procedure had to be performed many years after PEBD. Our aims were to find the most characteristic early microscopic features of the disease as well as to compare changes in the liver biopsy specimens at the time of diagnosis and long-time (more than 10 years) after a surgical procedure. We examined retrospectively 8 liver biopsies from 4 PFIC2 patients comparing the results from the first biopsies done at the time of PFIC diagnosis and the second ones, done many years after PEBD. The characteristic lobular rosette formations of hepatocytes were found in all patients at the time of diagnosis. Cholestasis was observed in each patient, but only in two of them, centrally located bile plugs were found. The majority of hepatocytes showed degenerative changes from mild to severe degree. In the follow-up biopsies, cholestasis completely disappeared in 3 patients and decreased significantly in 1 other patient. Based on Batts and Ludwig fibrosis scoring system, the liver fibrosis had resolved in two out of three patients. The formation of lobular rosettes with centrally located bile plugs and degenerative changes of hepatocytes seem to be the most characteristic microscopic features in early liver biopsies in PFIC2 patients. Partial external biliary diversion significantly improved the clinical, anthropological, biochemical as well histological outcome of the patients.


Assuntos
Colestase Intra-Hepática/patologia , Colestase Intra-Hepática/cirurgia , Hepatócitos/patologia , Cirrose Hepática/patologia , Adolescente , Criança , Seguimentos , Humanos , Cirrose Hepática/diagnóstico , Estudos Retrospectivos , Resultado do Tratamento
13.
PLoS Pathog ; 15(9): e1008021, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31525236

RESUMO

Hepatitis C virus (HCV) is a positive-strand RNA virus replicating in a membranous replication organelle composed primarily of double-membrane vesicles (DMVs) having morphological resemblance to autophagosomes. To define the mechanism of DMV formation and the possible link to autophagy, we conducted a yeast two-hybrid screening revealing 32 cellular proteins potentially interacting with HCV proteins. Among these was the Receptor for Activated Protein C Kinase 1 (RACK1), a scaffolding protein involved in many cellular processes, including autophagy. Depletion of RACK1 strongly inhibits HCV RNA replication without affecting HCV internal ribosome entry site (IRES) activity. RACK1 is required for the rewiring of subcellular membranous structures and for the induction of autophagy. RACK1 binds to HCV nonstructural protein 5A (NS5A), which induces DMV formation. NS5A interacts with ATG14L in a RACK1 dependent manner, and with the ATG14L-Beclin1-Vps34-Vps15 complex that is required for autophagosome formation. Both RACK1 and ATG14L are required for HCV DMV formation and viral RNA replication. These results indicate that NS5A participates in the formation of the HCV replication organelle through interactions with RACK1 and ATG14L.


Assuntos
Hepatite C/metabolismo , Hepatite C/virologia , Proteínas de Neoplasias/metabolismo , Receptores de Quinase C Ativada/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Autofagossomos/metabolismo , Autofagossomos/virologia , Autofagia , Proteínas Relacionadas à Autofagia/metabolismo , Linhagem Celular , Hepacivirus/genética , Hepacivirus/patogenicidade , Hepacivirus/fisiologia , Hepatite C/patologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Hepatócitos/virologia , Interações entre Hospedeiro e Microrganismos/fisiologia , Humanos , Redes e Vias Metabólicas , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , RNA Viral/biossíntese , Técnicas do Sistema de Duplo-Híbrido , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo , Replicação Viral
14.
Int J Mol Sci ; 20(18)2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31491992

RESUMO

Hepatocyte death is critical for the pathogenesis of liver disease progression, which is closely associated with endoplasmic reticulum (ER) stress responses. However, the molecular basis for ER stress-mediated hepatocyte injury remains largely unknown. This study investigated the effect of ER stress on dual-specificity phosphatase 5 (DUSP5) expression and its role in hepatocyte death. Analysis of Gene Expression Omnibus (GEO) database showed that hepatic DUSP5 levels increased in the patients with liver fibrosis, which was verified in mouse models of liver diseases with ER stress. DUSP5 expression was elevated in both fibrotic and acutely injured liver of mice treated with liver toxicants. Treatment of ER stress inducers enhanced DUSP5 expression in hepatocytes, which was validated in vivo condition. The induction of DUSP5 by ER stress was blocked by either treatment with a chemical inhibitor of the protein kinase RNA-like endoplasmic reticulum kinase (PERK) pathway, or knockdown of C/EBP homologous protein (CHOP), whereas it was not affected by the silencing of IRE1 or ATF6. In addition, DUSP5 overexpression decreased extracellular-signal-regulated kinase (ERK) phosphorylation, but increased cleaved caspase-3 levels. Moreover, the reduction of cell viability under ER stress condition was attenuated by DUSP5 knockdown. In conclusion, DUSP5 expression is elevated in hepatocytes by ER stress through the PERK-CHOP pathway, contributing to hepatocyte death possibly through ERK inhibition.


Assuntos
Fosfatases de Especificidade Dupla/genética , Estresse do Retículo Endoplasmático , Hepatócitos/metabolismo , Transdução de Sinais , Fator de Transcrição CHOP/metabolismo , eIF-2 Quinase/metabolismo , Animais , Apoptose/genética , Morte Celular/genética , Expressão Gênica , Hepatócitos/patologia , Humanos , Hepatopatias/etiologia , Hepatopatias/metabolismo , Camundongos
15.
Vet Res Commun ; 43(4): 231-238, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31473888

RESUMO

This study was performed to evaluate the hepatocyte-derived microRNA (miR)-122 as novel diagnostic biomarker in canine lymphoma. Fifteen dogs were enrolled in this study. Dogs presented at Small Animal Teaching Hospital, Faculty of Veterinary Medicine, Cairo University. Dogs were divided into 8 clinically healthy dogs act as control and 7 clinically ill dogs. All dogs were subjected to clinical, ultrasonographic, hemato-biochemical and ultrasound-guided fine-needle biopsy for cytological and histopathological investigations. On the basis of these results, 7 dogs were found to be suffering from multicentric lymphoma involving liver. Serum hepatocyte-derived miRA-122 was determined by real-time quantitative polymerase chain reaction in all dogs. Multicentric lymphoma involving liver manifested by inappetance for several days, depression and peripheral lymphadenopathy. Hematological examination showed significant lymphocytosis. Serum biochemical analysis revealed significant increase in ALT, AST, ALP compared to control dogs. Ultrasonography revealed hypoechoic lymphoid aggregation at area of "porta hepatis" and circumscribed hypoechoic nodule interrupt liver parenchyma. Cytology revealed infiltration of liver tissue by lymphoblast cells and histopathology revealed diffuse infiltration of hepatic sinusoids and portal area by uniform population of small lymphocytes. Serum miRNA-122 analysis showed a significant increase represented as 9.00 fold in canine multicentric lymphoma involving liver. Serum hepatocyte-derived miRNA-122 is of diagnostic value, non invasive, stable and easily measurable blood biomarker for the detection of hepatocellular injury in dogs with multicentric lymphoma involving liver.


Assuntos
Doenças do Cão/sangue , Doenças do Cão/fisiopatologia , Regulação Neoplásica da Expressão Gênica , Hepatopatias/veterinária , Fígado/patologia , Linfoma/veterinária , MicroRNAs/sangue , Animais , Doenças do Cão/diagnóstico , Cães , Hepatócitos/patologia , Hepatopatias/sangue , Hepatopatias/complicações , Hepatopatias/diagnóstico , Linfoma/sangue , Linfoma/complicações , Linfoma/diagnóstico , MicroRNAs/genética
16.
Int J Mol Sci ; 20(15)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370360

RESUMO

BACKGROUND: Gadolinium chloride (GdCl3) has been reported to attenuate liver injury caused by a variety of toxicants. Gap junctional intercellular communication (GJIC) is thought to be essential in controlling liver homeostasis and pathology. Here we evaluate the effects of GdCl3 on functional GJIC and connexin expression in mouse models and primary hepatocytes. METHODS: Mice were administered GdCl3 intraperitoneally the day before a carbon tetrachloride (CCl4) injection or bile duct ligation (BDL) operation. Primary hepatocytes were treated with CCl4 or lipopolysaccharides (LPS), with or without GdCl3. A scrape loading/dye transfer assay was performed to assess the GJIC function. The expression of connexins was examined by real-time reverse transcription polymerase chain reaction (RT-PCR), western blot and immunofluorescent staining. RESULTS: CCl4 treatment or the BDL operation led to the dysfunction of GJIC and a down-regulation of Cx32 and Cx26 in injured liver. GdCl3 administration restored GJIC function between hepatocytes by facilitating the transfer of fluorescent dye from one cell into adjacent cells via GJIC, and markedly prevented the decrease of Cx32 and Cx26 in injured liver. In primary hepatocytes, CCl4 or LPS treatment induced an obvious decline of Cx32 and Cx26, whereas GdCl3 pretreatment prevented the down-regulation of connexins. In vivo GdCl3 protected hepatocytes and attenuated the liver inflammation and fibrosis in liver injury mouse models. CONCLUSION: GdCl3 administration protects functional GJIC between hepatocytes, and prevents the decrease of connexin proteins at mRNA and protein levels during liver injury, leading to the alleviation of chronic liver injury.


Assuntos
Anti-Inflamatórios/farmacologia , Comunicação Celular/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Gadolínio/farmacologia , Junções Comunicantes/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Animais , Ductos Biliares/cirurgia , Tetracloreto de Carbono/administração & dosagem , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Conexinas/agonistas , Conexinas/genética , Conexinas/metabolismo , Regulação da Expressão Gênica , Hepatócitos/metabolismo , Hepatócitos/patologia , Ligadura , Lipopolissacarídeos/administração & dosagem , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos , Cultura Primária de Células
17.
Biomed Res Int ; 2019: 3103946, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31428632

RESUMO

Suitable content of iron is essential for human body, but iron overload is associated with many kinds of diseases including chronic liver damage. Recently, researchers find that iron overload promotes hepatocyte autophagy and apoptosis. However, the mechanism of iron overload in liver damage remains unclear. In this study, Lo2 cells were selected as the research object, iron dextran was a model drug, and astragaloside IV was a therapeutic drug to explore the role of iron overload. MTT assay and Annexin/PI double staining were used to measure cell viability and apoptosis. Ultrastructure was observed by transmission electron microscopy. The expression levels of apoptosis and autophagy-related proteins were determined by real-time PCR and Western Blot. The results showed that iron dextran could significantly inhibit Lo2 cell viability and increase the apoptosis rate, while astragaloside IV could reverse the inhibition of Lo2 cell viability and decrease the apoptosis rate. Transmission electron microscopy showed a significant increase in the number of autophagosomes after administration of iron dextran, and the application of astragaloside IV reduced the production of autophagosomes. LC3II/I was significantly upregulated in the model group but decreased in the astragaloside IV treatment group, and P62 showed the opposite trend. Iron dextran significantly upregulated the expression of Bax and downregulated Bcl2, while astragaloside IV reversed this trend. Finally, the inhibition of hepcidin caused by iron dextran was counteracted by astragaloside IV. In conclusion, the experimental results show that the iron overload model mainly induces excessive autophagy and apoptosis of hepatocytes, thus causing damage to hepatocytes, but astragaloside IV plays a certain therapeutic role in reversing this damage.


Assuntos
Hepatócitos/metabolismo , Sobrecarga de Ferro/prevenção & controle , Fígado/lesões , Fígado/metabolismo , Saponinas/farmacologia , Triterpenos/farmacologia , Autofagossomos/metabolismo , Autofagossomos/patologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Hepatócitos/patologia , Humanos , Sobrecarga de Ferro/induzido quimicamente , Sobrecarga de Ferro/metabolismo , Sobrecarga de Ferro/patologia , Complexo Ferro-Dextran/efeitos adversos , Complexo Ferro-Dextran/farmacologia , Fígado/patologia , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteína X Associada a bcl-2/metabolismo
18.
Toxicol Lett ; 316: 183-193, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31437515

RESUMO

Olanzapine, a representative of antipsychotics, is a first-line drug for treatment of schizophrenia. However, olanzapine-induced liver steatosis limits its clinical utilization. This study is to explore the mechanism of liver steatosis induced by olanzapine based on the regulation of transporters involved in uptake and oxidation of fatty acids. Our results revealed that 12-week oral administration of olanzapine increased hepatic triglyceride(TG), caused liver steatosis. Our further studies showed that the expression of fatty acid transporter 2(FATP2) and fatty acid binding protein 1(FABP1) were up-regulated in liver of female mice after 12-week olanzapine exposure, as well as in primary mouse hepatocytes treated with olanzapine. Olanzapine treatment also reduced hepatic ß-hydroxybutyrate level (indicator of fatty acid ß-oxidation), meanwhile, the L-carnitine (L-Car) concentration in liver of olanzapine group was significantly lower than that in control group. Further study demonstrated that both mRNA and protein expression of hepatic OCTN2 (carnitine/organic cation transporter 2) were obviously down-regulated in male mice after 12-week olanzapine treatment. Also, olanzapine markedly inhibited L-Car uptake in MDCK-hOCTN2 cells (1.06 µM of IC50), HepG2 cells and primary mouse hepatocytes. Supplementation of L-Car attenuated hepatic TG rise and improved simple steatosis in olanzapine treatment mice. Taken together, up-regulation of FATP2/FABP1 and down-regulation/inhibition of hepatic OCTN2 probably contribute to olanzapine-induced liver steatosis. Supplementation of L-Car is a promising strategy to attenuate olanzapine-induced simple steatosis.


Assuntos
Antipsicóticos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Coenzima A Ligases/metabolismo , Proteínas de Ligação a Ácido Graxo/metabolismo , Fígado Gorduroso/induzido quimicamente , Hepatócitos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Olanzapina/toxicidade , Membro 5 da Família 22 de Carreadores de Soluto/antagonistas & inibidores , Adulto , Animais , Carnitina/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Coenzima A Ligases/genética , Cães , Proteínas de Ligação a Ácido Graxo/genética , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Fígado Gorduroso/prevenção & controle , Feminino , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Fígado/metabolismo , Fígado/patologia , Células Madin Darby de Rim Canino , Masculino , Camundongos Endogâmicos C57BL , Membro 5 da Família 22 de Carreadores de Soluto/genética , Membro 5 da Família 22 de Carreadores de Soluto/metabolismo , Regulação para Cima
19.
Biomed Pharmacother ; 117: 109083, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31387169

RESUMO

BACKGROUND: Mitochondrial dysfunction is an important mechanism of non-alcoholic fatty liver disease (NAFLD). Developing mitochondrial regulators/nutrients from natural products to remedy mitochondrial dysfunction represent attractive strategies for NAFLD therapy. In China, Polygonatum kingianum (PK) has been used as a herb and food nutrient for centuries. So far, studies in which the effects of PK on NAFLD are evaluated are lacking. Our study aims at identifying the effects and mechanism of action of PK on NAFLD based on mitochondrial regulation. METHODS: A NAFLD rat model was induced by a high-fat diet (HFD) and rats were intragastrically given PK (1, 2 and 4 g/kg) for 14 weeks. Changes in body weight, food intake, histological parameters, organ indexes, biochemical parameters and mitochondrial indicators involved in oxidative stress, energy metabolism, fatty acid metabolism, and apoptosis were investigated. RESULTS: PK significantly inhibited the HFD-induced increase of alanine transaminase, aspartate transaminase, total cholesterol (TC), and low density lipoprotein cholesterol in serum, and TC and triglyceride in the liver. In addition, PK reduced high density lipoprotein cholesterol and liver enlargement without affecting food intake. PK also remarkably inhibited the HFD-induced increase of malondialdehyde and the reduction of superoxide dismutase, glutathione peroxidase, ATP synthase, and complex I and II, in mitochondria. Moreover, mRNA expression of carnitine palmitoyl transferase-1 and uncoupling protein-2 was significantly up-regulated and down-regulated after PK treatment, respectively. Finally, PK notably inhibited the HFD-induced increase of caspase 9, caspase 3 and Bax expression in hepatocytes, and the decrease of expression of Bcl-2 in hepatocytes and cytchrome c in mitochondria. CONCLUSION: PK alleviated HFD-induced NAFLD by promoting mitochondrial functions. Thus, PK may be useful mitochondrial regulators/nutrients to remedy mitochondrial dysfunction and alleviate NAFLD.


Assuntos
Mitocôndrias/efeitos dos fármacos , Doenças Mitocondriais/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Preparações de Plantas/farmacologia , Polygonatum/química , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Caspases/metabolismo , China , Dieta Hiperlipídica/efeitos adversos , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Resistência à Insulina/fisiologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Doenças Mitocondriais/metabolismo , Doenças Mitocondriais/patologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Triglicerídeos/metabolismo , Regulação para Cima/efeitos dos fármacos
20.
Ecotoxicol Environ Saf ; 183: 109465, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31376806

RESUMO

Our group found that long-term low-dose exposure to hexavalent chromium [Cr(VI)] in L-02 hepatocytes resulted in premature senescence, which accompanied by the increased expression of Clusterin (CLU), but the functional role of CLU in premature senescence has never been explored. In the present study, the CLU overexpressed or silenced L-02 hepatocytes were established by lentiviral vector transfection. Cell viability assay, cell cycle analysis, western blotting, plate clone formation assay, and confocal microcopy were performed. The results indicated that Cr(VI)-induced premature senescence was associated with phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway inhibition, and high expression of CLU in the senescent cells exerted its functional role of promoting cell proliferation. CLU could complex with eukaryotic translation initiation factor 3 subunit I (EIF3I) and prevent its degradation, leading to the increase of AKT activity in Cr(VI)-exposed senescent hepatocytes. Blockage of the PI3K/AKT pathway with its inhibitor LY294002 eliminated the inhibitory effect of CLU on Cr(VI)-induced premature senescence. We concluded that high expression of CLU suppressed Cr(VI)-induced premature senescence through activation of PI3K/AKT pathway, which will provide the experimental basis for the study of Cr(VI)-induced liver cancer, especially for the elucidation of the mechanism of liver cancer cells escaping from senescence.


Assuntos
Senescência Celular/efeitos dos fármacos , Cromo/toxicidade , Clusterina/genética , Hepatócitos/efeitos dos fármacos , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Senescência Celular/genética , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
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