Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 142
Filtrar
1.
BMC Gastroenterol ; 20(1): 53, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32138675

RESUMO

BACKGROUND: Prognostic value or clinical implications of fluid status monitoring in liver cirrhosis are not fully elucidated. Tolvaptan, an orally available, selective vasopressin V2-receptor antagonist approved for hyponatremia in the United States and European Union. It is also used for cirrhotic ascites at a relatively low dose (3.75 mg to 7.5 mg) in Japan, exerts its diuretic function by excreting electrolyte-free water. We hypothesized that bioimpedance-defined dynamic changes in fluid status allow prediction of response of V2 antagonism and survival in cirrhotic patients. METHODS: In this prospective observational study, 30 patients with decompensated liver cirrhosis who were unresponsive to conventional diuretics were enrolled. Detailed serial changes of body composition that were assessed by using non-invasive bioimpedance analysis (BIA) devices, along with biochemical studies, were monitored at 5 time points. RESULTS: Sixteen patients were classified as short-term responders (53%). Rapid and early decrease of BIA-defined intracellular water, as soon as 6 h after the first dose (ΔICWBIA%-6 h), significantly discriminated responders from non-responders (AUC = 0.97, P < 0.0001). ΔICWBIA%-6 h was highly correlated with the change of BIA-derived phase angle of trunk, e.g. reduced body reactance operated at 50 kHz after 24 h of the first dose of tolvaptan. Lower baseline blood urea nitrogen and lower serum aldosterone were predictive of a rapid and early decrease of ICWBIA. A rapid and early decrease of ICWBIA in response to tolvaptan was also predictive of a better transplant-free survival. CONCLUSIONS: BIA-defined water compartment monitoring may help predict short-term efficacy and survival in decompensated cirrhotic patients treated with tolvaptan.


Assuntos
Antagonistas dos Receptores de Hormônios Antidiuréticos/uso terapêutico , Ascite/tratamento farmacológico , Líquidos Corporais , Cirrose Hepática/tratamento farmacológico , Tolvaptan/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Antagonistas dos Receptores de Hormônios Antidiuréticos/administração & dosagem , Impedância Elétrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Tolvaptan/administração & dosagem
2.
Int J Mol Sci ; 22(1)2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33383848

RESUMO

Obesity has become a global medical problem. The upregulation of senescence-related markers in adipose tissue may cause impairment of adipose tissue and disorders of systemic metabolism. Weight control through diet has been found to ameliorate senescence in the adipose tissue. Exercise is also important in maintaining a healthy lifestyle, however, very few researchers have examined the relationship between senescence-related markers in adipose tissue. Dietary restriction is also reported to have a legacy effect, wherein the effects are maintained for some periods after the termination of the intervention. However, very few researchers have examined the relationship between exercise and senescence-related markers in adipose tissue. Besides, there is no study on the long-term effects of exercise. Hence, we investigated whether the exercise could change the expression of senescence-related genes in the visceral adipose tissue of young mice and whether there was a legacy effect of exercise for 10 weeks after the termination of exercise. Four-week-old male ICR mice were assigned to one of the three groups: 20 weeks of sedentary condition, 20 weeks of voluntary wheel running exercise, or 10 weeks of exercise followed by 10 weeks of sedentary condition. The mice showed decreased expression in genes related to senescence and senescence-associated secretory phenotype, such as p53, p16, and IL-6, in the visceral adipose tissue in response to exercise. These effects were maintained for 10 weeks after the mice stopped exercising. Our study is the first report that exercise reduces the expression of senescence-related genes in the visceral adipose tissue of young mice, and that exercise causes the legacy effect.


Assuntos
Envelhecimento/genética , Biomarcadores , Regulação da Expressão Gênica , Gordura Intra-Abdominal/metabolismo , Condicionamento Físico Animal , Adipocinas/metabolismo , Animais , Biologia Computacional/métodos , Metabolismo Energético , Perfilação da Expressão Gênica , Ontologia Genética , Glucose/metabolismo , Masculino , Camundongos
3.
BMC Cancer ; 18(1): 680, 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-29940898

RESUMO

BACKGROUND: We previously showed that knockdown of nuclear factor E2-related factor 2 (Nrf2) resulted in suppression of hepatitis C virus (HCV) infection. In this study, whether brusatol, an Nrf2 inhibitor, has dual anti-HCV and anticancer effects was explored. METHODS: The anti-HCV effect of brusatol was investigated by analyzing HCV RNA and proteins in a hepatic cell line persistently-infected with HCV, HPI cells, and by analyzing HCV replication in a replicon-replicating hepatic cell line, OR6 cells. Then, dual anti-HCV and anticancer effects of brusatol and enhancement of the effects by the combination of brusatol with anticancer drugs including sorafenib, which has been reported to have the dual effects, were then investigated. RESULTS: Brusatol suppressed the persistent HCV infection at both the RNA and protein levels in association with a reduction in Nrf2 protein in the HPI cells. Analysis of the OR6 cells treated with brusatol indicated that brusatol inhibited HCV persistence by inhibiting HCV replication. Combination of brusatol with an anticancer drug not only enhanced the anticancer effect but also, in the case of the combination with sorafenib, strongly suppressed HCV infection. CONCLUSIONS: Brusatol has dual anti-HCV and anticancer effects and can enhance the comparable effects of sorafenib. There is therefore the potential for combination therapy of brusatol and sorafenib for HCV-related hepatocellular carcinoma.


Assuntos
Antineoplásicos/farmacologia , Antivirais/farmacologia , Hepatite C/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Quassinas/farmacologia , Linhagem Celular Tumoral , Humanos , Quassinas/uso terapêutico , RNA Viral/análise , Sorafenibe/farmacologia , Transcriptoma , Replicação Viral/efeitos dos fármacos
4.
J Clin Biochem Nutr ; 63(2): 123-128, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30279623

RESUMO

The exact mechanisms of hepatocellular carcinoma development in non-alcoholic steatohepatitis remain unclear. In this study, we used a new class of high-fat diet, which could induce hepatocellular carcinoma development without the use of general chemical carcinogens or knockout mice. We investigated the correlation between hepatocellular carcinoma and oxidative stress/anti-oxidant effects after depletion of the gut microbiota by treatment with antibiotics. Mice fed with the steatohepatitis-inducing high-fat diet (STHD-01) for 41 weeks developed hepatocellular carcinoma. Antibiotic-treatment in mice fed with STHD-01 significantly depleted the gut microbiota and significantly ameliorated liver injury/histology. The tumor numbers of hepatocellular carcinoma were dramatically decreased by the antibiotics-treatment. We analyzed the factors involved in oxidative stress and anti-oxidant effects. Oxidative stress was elevated in mice fed with STHD-01, whereas some anti-oxidant factors were significantly elevated after antibiotics treatment. These results suggest that the gut microbiota is a key factor in improving oxidative stress induced by STHD-01 feeding.

5.
Cancer Sci ; 108(4): 678-684, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28092415

RESUMO

Tumor stem cells with self-renewal and multipotent capacity play critical roles in the initiation and progression of cancer. Recently, a new 3-D culture system known as organoid culture has been developed, allowing Lgr5-positive stem cells to form organoids that resemble the properties of original tissues. Here we established organoids derived from intestinal tumors of Apcmin/+ mice and normal intestinal epithelia of C57BL/6J mice and investigated the roles of microRNA (miRNA) in intestinal tumor organoids. The results of microarray analyses revealed that expression of the cluster miRNAs, miR-194 and miR-215 was markedly suppressed in intestinal tumor organoids in comparison with organoids derived from normal intestinal epithelia. Enforced expression of miR-194 resulted in inhibition of E2f3, a positive regulator of the cell cycle and growth suppression of intestinal tumor organoids. In addition, enforced expression of miR-215 suppressed the cancer stem cell signature through downregulation of intestinal stem cell markers including Lgr5. These findings indicate that the miRNA cluster including miR-194 and miR-215 plays important roles in suppressing the growth and attenuating the stemness of intestinal tumor organoids.


Assuntos
Transformação Celular Neoplásica/genética , Mucosa Intestinal/metabolismo , Neoplasias Intestinais/genética , MicroRNAs/genética , Organoides/metabolismo , Regiões 3' não Traduzidas/genética , Proteínas Adaptadoras de Transdução de Sinal , Idoso , Animais , Western Blotting , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Fator de Transcrição E2F3/genética , Fator de Transcrição E2F3/metabolismo , Epirregulina/genética , Epirregulina/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/metabolismo , Técnicas de Cultura de Órgãos , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
6.
J Hepatol ; 67(4): 780-790, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28554874

RESUMO

BACKGROUND & AIMS: Although obesity is a risk factor for acute liver failure, the pathogenic mechanisms are not yet fully understood. High cholesterol (HC) intake, which often underlies obesity, is suggested to play a role in the mechanism. We aimed to elucidate the effect of a HC diet on acetaminophen-induced acute liver injury, the most frequent cause of acute liver failure in the USA. METHODS: C57BL/6 Toll-like receptor 9 (TLR9) knockout (Tlr9-/-) mice and their Tlr9+/+ littermates were fed an HC diet for fourweeks and then treated with acetaminophen. Liver sinusoidal endothelial cells (LSECs) were isolated from the mice for in vivo and in vitro analyses. RESULTS: The HC diet exacerbated acetaminophen-induced acute liver injury in a TLR9/inflammasome pathway-dependent manner. LSECs played a major role in the cholesterol loading-induced exacerbation. The accumulation of free cholesterol in the endolysosomes in LSECs enhanced TLR9-mediated signaling, thereby exacerbating the pathology of acetaminophen-induced liver injury through the activation of the TLR9/inflammasome pathway. The accumulation of free cholesterol in LSEC endolysosomes induced a dysfunction of the Rab7 membrane trafficking recycling mechanism, thus disrupting the transport of TLR9 from late endosomes to the lysosomes. Consequently, the level of active TLR9 in the late endosomes increased, thereby enhancing TLR9 signaling in LSECs. CONCLUSIONS: HC intake exaggerated acetaminophen-induced acute liver injury via free cholesterol accumulation in LSECs, demonstrating a novel role of free cholesterol as a metabolic factor in TLR9 signal regulation and pathologies of acetaminophen-induced liver injury. Therapeutic approaches may target this pathway. Lay summary: High cholesterol intake exacerbated acetaminophen-induced acute liver injury via the accumulation of free cholesterol in the endolysosomes of liver sinusoidal endothelial cells. This accumulation enhanced Toll-like receptor 9 signaling via impairment of its membrane trafficking mechanism. Thus, free cholesterol accumulation, as an underlying metabolic factor, exacerbated the pathology of acetaminophen-induced liver injury through activation of the TLR9/inflammasome pathway.


Assuntos
Acetaminofen/toxicidade , Colesterol/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Receptor Toll-Like 9/metabolismo , Animais , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Dieta Hiperlipídica/efeitos adversos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Inflamassomos/efeitos dos fármacos , Inflamassomos/metabolismo , Lisossomos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oligodesoxirribonucleotídeos/farmacologia , Transporte Proteico , Transdução de Sinais , Receptor Toll-Like 9/deficiência , Receptor Toll-Like 9/genética , Proteínas rab de Ligação ao GTP/metabolismo , proteínas de unión al GTP Rab7
8.
BMC Gastroenterol ; 17(1): 106, 2017 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-29041907

RESUMO

BACKGROUND: Spontaneous bacterial peritonitis (SBP) is often difficult to diagnose because bacteria in ascites cannot be detected accurately by conventional culture. In situ hybridization (ISH) was previously developed for rapid detection of genes from bacteria phagocytized by neutrophils. SBP may develop after bacteria enter into the systemic circulation following bacterial translocation. Therefore, we performed ISH to identify bacteria in blood samples collected from patients with decompensated liver cirrhosis (LC). METHODS: In this retrospective study, peripheral blood samples were collected from 60 patients with decompensated LC, and bacteria were detected by both blood culture and ISH. Moreover, 35 patients underwent paracentesis for diagnosis of SBP. RESULTS: Eight of 35 patients were diagnosed with SBP by polymorphonuclear neutrophil counts, and one patient was diagnosed with bacterascites. Seven of the nine patients showed positive results for ISH, whereas bacteria were detected in only two cases by blood culture. Thirty-seven of 60 cases (62%) showed positive results for ISH, whereas only six samples (10%) were positive by blood culture analysis. Compared with the 23 cases of negative ISH, the 37 cases of positive ISH showed a higher frequency of fever, higher Child-Pugh scores, and lower albumin levels. CONCLUSIONS: Detection of bacteria by ISH suggested that bacterial translocation, which cannot be proven by conventional culture, occurred in these patients, and that ISH could be helpful for the early diagnosis of some types of infection and prevention of SBP in these patients.


Assuntos
Infecções Bacterianas/diagnóstico , DNA Bacteriano/sangue , Hibridização In Situ , Cirrose Hepática/microbiologia , Peritonite/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Ascite/microbiologia , Translocação Bacteriana , Técnicas Bacteriológicas , Feminino , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Neutrófilos , Peritonite/microbiologia , Estudos Retrospectivos
9.
BMC Gastroenterol ; 17(1): 136, 2017 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-29187142

RESUMO

BACKGROUND: The gut microbiota plays crucial roles in the development of non-alcoholic steatohepatitis (NASH). However, the precise mechanisms by which alterations of the gut microbiota and its metabolism contributing to the pathogenesis of NASH are not yet fully elucidated. METHODS: Mice were fed with a recently reported new class of high-fat diet (HFD), steatohepatitis-inducing HFD (STHD)-01 for 9 weeks. The composition of the gut microbiota was analyzed by T-RFLP. Luminal metabolome was analyzed using capillary electrophoresis and liquid chromatography time-of-flight mass spectrometry (CE- and LC-TOFMS). RESULTS: Mice fed the STHD-01 developed NASH-like pathology within a short period. Treatment with antibiotics prevented the development of NASH by STHD-01. The composition of the gut microbiota and its metabolic activities were markedly perturbed in the STHD-01-fed mice, and antibiotic administration normalized these changes. We identified that long-chain saturated fatty acid and n-6 fatty acid metabolic pathways were significantly altered by STHD-01. Of note, the changes in gut lipidome caused by STHD-01 were mediated by gut microbiota, as the depletion of the gut microbiota could reverse the perturbation of these metabolic pathways. A saturated long-chain fatty acid, palmitic acid, which accumulated in the STHD-01 group, activated liver macrophages and promoted TNF-α expression. CONCLUSIONS: Lipid metabolism by the gut microbiota, particularly the saturation of fatty acids, affects fat accumulation in the liver and subsequent liver inflammation in NASH.


Assuntos
Dieta Hiperlipídica , Ácidos Graxos/metabolismo , Microbioma Gastrointestinal/fisiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/microbiologia , Animais , Movimento Celular , Fígado/metabolismo , Fígado/microbiologia , Fígado/patologia , Macrófagos/patologia , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/patologia , Transcrição Gênica , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
10.
Int J Mol Sci ; 18(6)2017 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-28545228

RESUMO

Cholangiocarcinoma is an epithelial malignancy arising in the region between the intrahepatic bile ducts and the ampulla of Vater at the distal end of the common bile duct. The effect of current chemotherapy regimens against cholangiocarcinoma is limited, and the prognosis of patients with cholangiocarcinoma is poor. Aberrant DNA methylation and histone modification induce silencing of tumor suppressor genes and chromosomal instability during carcinogenesis. Studies have shown that the tumor suppressor genes and microRNAs (miRNAs) including MLH1, p14, p16, death-associated protein kinase (DAPK), miR-370 and miR-376c are frequently methylated in cholangiocarcinoma. Silencing of these tumor suppressor genes and miRNAs plays critical roles in the initiation and progression of cholangiocarcinoma. In addition, recent studies have demonstrated that DNA methylation inhibitors induce expression of endogenous retroviruses and exert the anti-tumor effect of via an anti-viral immune response. Aberrant DNA methylation of tumor suppressor genes and miRNAs could be a powerful biomarker for the diagnosis and treatment of cholangiocarcinoma. Epigenetic therapy with DNA methylation inhibitors holds considerable promise for the treatment of cholangiocarcinoma through the reactivation of tumor suppressor genes and miRNAs as well as the induction of an anti-viral immune response.


Assuntos
Biomarcadores Tumorais/genética , Colangiocarcinoma/genética , Metilação de DNA/genética , Animais , Regulação Neoplásica da Expressão Gênica/genética , Humanos
11.
Cancer ; 122(13): 2041-9, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27062278

RESUMO

BACKGROUND: Curative treatment options for patients with early stage hepatocellular carcinoma (HCC) include resection, liver transplantation, and percutaneous ablation therapy. However, even patients with solitary HCC are not always amenable to these treatments. The authors prospectively investigated the clinical outcomes of patients who received stereotactic body radiotherapy (SBRT) for solitary HCC. METHODS: A phase 2 study involving SBRT and optional transarterial chemoembolization (TACE) was conducted in patients with Child-Pugh grade A or B and underlying, solitary HCC (greatest tumor dimension, ≤4 cm) who were unsuitable candidates for resection and radiofrequency ablation. The prescription dose was 35 to 40 grays in 5 fractions. The primary endpoint was 3-year local tumor control. RESULTS: From 2007 to 2012, 101 patients were enrolled, and 90 were evaluable with a median follow-up of 41.7 months (range, 6.8-96.2 months). Thirty-two patients were treatment-naïve, 20 were treated for newly diagnosed intrahepatic failure, and 38 were treated for residual or recurrent HCC as salvage therapy. Thirty-two patients did not receive TACE, 48 received insufficient TACE, and 10 attained full lipiodol accumulation. The 3-year local control rate was 96.3%, the 3-year liver-related cause-specific survival rate was 72.5%, and the overall survival rate was 66.7%. Grade 3 laboratory abnormalities were observed in 6 patients, and 8 patients had Child-Pugh scores that worsened by 2 points. CONCLUSIONS: SBRT achieved high local control and overall survival with feasible toxicities for patients with solitary HCC, despite rather stringent conditions. SBRT can be effective against solitary HCC in treatment-naive, intrahepatic failure, residual disease, and recurrent settings, taking advantage of its distinctive characteristics. Cancer 2016;122:2041-9. © 2016 American Cancer Society.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/estatística & dados numéricos , Neoplasias Hepáticas/terapia , Radiocirurgia/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/patologia , Terapia Combinada , Óleo Etiodado/administração & dosagem , Óleo Etiodado/uso terapêutico , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento
12.
BMC Cancer ; 16(1): 732, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27629773

RESUMO

BACKGROUND: It is generally accepted that the energy resources of cancer cells rely on anaerobic metabolism or the glycolytic system, even if they have sufficient oxygen. This is known as the Warburg effect. The cells skillfully survive under hypoglycemic conditions when their circumstances change, which probably at least partly involves microRNA (miRNA)-mediated regulation. METHODS: To determine how cancer cells exploit miRNA-mediated epigenetic mechanisms to survive in hypoglycemic conditions, we used DNA microarray analysis to comprehensively and simultaneously compare the expression of miRNAs and mRNAs in the HepG2 human hepatoma cell line and in cultured normal human hepatocytes. RESULTS: The hypoglycemic condition decreased the expression of miRNA-17-5p and -20a-5p in hepatoma cells and consequently upregulated the expression of their target gene p21. These regulations were also confirmed by using antisense inhibitors of these miRNAs. In addition to this change, the hypoglycemic condition led to upregulated expression of heat shock proteins and increased resistance to caspase-3-induced apoptosis. However, we could not identify miRNA-mediated regulations, despite using comprehensive detection. Several interesting genes were also found to be upregulated in the hypoglycemic condition by the microarray analysis, probably because of responding to this cellular stress. CONCLUSION: These results suggest that cancer cells skillfully survive in hypoglycemic conditions, which frequently occur in malignancies, and that some of the gene regulation of this process is manipulated by miRNAs.


Assuntos
Carcinoma Hepatocelular/genética , Hipoglicemia/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Biomarcadores , Caspase 3/metabolismo , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Bases de Dados de Ácidos Nucleicos , Epigênese Genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Ligação Genética , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Família Multigênica , RNA Mensageiro/genética
13.
Pediatr Radiol ; 46(10): 1409-17, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27300741

RESUMO

BACKGROUND: Biliary atresia commonly leads to liver fibrosis and cirrhotic complications, including esophageal varices. OBJECTIVE: To evaluate liver and spleen stiffness measurements using acoustic radiation force impulse (ARFI) imaging for diagnosing grade of liver fibrosis and predicting the presence of esophageal varices in patients treated for biliary atresia. MATERIALS AND METHODS: ARFI imaging of the spleen and native liver was performed in 28 patients with biliary atresia. We studied the relation between ARFI imaging values and liver histology findings (n=22), upper gastrointestinal endoscopy findings (n=16) and several noninvasive test results. Diagnostic accuracy was assessed using receiver operating characteristic curve analyses. RESULTS: Liver stiffness measurements exhibited a significant difference among the different grades of liver fibrosis (P=0.009), and showed higher values in patients with high-risk esophageal varices than in the other patients (P=0.04). The areas under the receiver operating characteristic curves of liver stiffness measurements for liver fibrosis grades ≥ F2, ≥F3 and = F4 were 0.83, 0.93 and 0.94, respectively. Patients with high-risk esophageal varices were preferentially diagnosed by the combined liver and spleen stiffness measurements (area under the curve, 0.92). CONCLUSION: Liver and spleen stiffness measurements using ARFI imaging are potential noninvasive markers for liver fibrosis and esophageal varices in patients treated for biliary atresia.


Assuntos
Atresia Biliar/complicações , Técnicas de Imagem por Elasticidade , Varizes Esofágicas e Gástricas/diagnóstico por imagem , Cirrose Hepática/diagnóstico por imagem , Adolescente , Adulto , Atresia Biliar/cirurgia , Criança , Pré-Escolar , Varizes Esofágicas e Gástricas/etiologia , Feminino , Humanos , Lactente , Cirrose Hepática/etiologia , Masculino , Projetos Piloto , Baço/diagnóstico por imagem
14.
Hepatology ; 59(1): 154-69, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23832448

RESUMO

UNLABELLED: Although nonalcoholic steatohepatitis (NASH) is associated with hypercholesterolemia, the underlying mechanisms of this association have not been clarified. We aimed to elucidate the precise role of cholesterol in the pathophysiology of NASH. C57BL/6 mice were fed a control, high-cholesterol (HC), methionine-choline-deficient (MCD), or MCD+HC diet for 12 weeks or a control, HC, high-fat (HF), or HF+HC diet for 24 weeks. Increased cholesterol intake accelerated liver fibrosis in both the mouse models without affecting the degree of hepatocellular injury or Kupffer cell activation. The major causes of the accelerated liver fibrosis involved free cholesterol (FC) accumulation in hepatic stellate cells (HSCs), which increased Toll-like receptor 4 protein (TLR4) levels through suppression of the endosomal-lysosomal degradation pathway of TLR4, and thereby sensitized the cells to transforming growth factor (TGF)ß-induced activation by down-regulating the expression of bone morphogenetic protein and activin membrane-bound inhibitor. Mammalian-cell cholesterol levels are regulated by way of a feedback mechanism mediated by sterol regulatory element-binding protein 2 (SREBP2), maintaining cellular cholesterol homeostasis. Nevertheless, HSCs were sensitive to FC accumulation because the high intracellular expression ratio of SREBP cleavage-activating protein (Scap) to insulin-induced gene (Insig) disrupted the SREBP2-mediated feedback regulation of cholesterol homeostasis in these cells. HSC activation subsequently enhanced the disruption of the feedback system by Insig-1 down-regulation. In addition, the suppression of peroxisome proliferator-activated receptor γ signaling accompanying HSC activation enhanced both SREBP2 and microRNA-33a signaling. Consequently, FC accumulation in HSCs increased and further sensitized these cells to TGFß-induced activation in a vicious cycle, leading to exaggerated liver fibrosis in NASH. CONCLUSION: These characteristic mechanisms of FC accumulation in HSCs are potential targets to treat liver fibrosis in liver diseases including NASH.


Assuntos
Colesterol/metabolismo , Fígado Gorduroso/complicações , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/etiologia , Animais , Colesterol/administração & dosagem , Modelos Animais de Doenças , Regulação para Baixo , Fígado Gorduroso/metabolismo , Cirrose Hepática/metabolismo , Ativação de Macrófagos , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , PPAR gama/metabolismo , RNA Mensageiro/metabolismo , Receptores de LDL/metabolismo , Transdução de Sinais , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Receptor 4 Toll-Like/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima
15.
Drug Metab Dispos ; 43(5): 691-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25713208

RESUMO

European studies have revealed that the ABCB11 c.1331T>C (V444A) polymorphism (rs2287622) C-allele frequency is higher among patients with drug-induced cholestasis. Given the low incidence of this disease, however, this association has not been sufficiently elucidated. We aimed to investigate the significance of this polymorphism in Japanese patients. We determined ABCB11 V444A polymorphism frequencies and HLA genotypes in two independent drug-induced cholestasis cohorts. Expression and taurocholate transport activity of proteins from 444A variants were analyzed using Madin-Darby canine kidney II cells. In cohort 1 (n = 40), the V444A polymorphism C-allele frequency (66%) was lower than that in controls (n = 190, 78%), but this difference was not significant (P = 0.09). In cohort 2 (n = 119), comprising patients with cholestatic (n = 19), hepatocellular (n = 74), and mixed (n = 26) liver injuries, the C-allele frequency was lower among patients with cholestatic liver injury (68%) than among those with hepatocellular (75%) or mixed liver injury (83%), although this difference was not significant. In cohort 1, HLA-A*0201 was observed more frequently in patients (22%) than in controls [11%; P = 0.003; odds ratio, 2.4 (95% confidence interval, 1.4-4.0)]. Taurocholate transport activity of 444A-encoded protein was significantly lower than that of 444V-encoded protein (81% of 444V, P < 0.05) because of the reduced protein stability. In conclusion, ABCB11 444A had slightly reduced transport activity, but it did not contribute to the occurrence of drug-induced cholestasis in Japanese patients. Therefore, genetic susceptibility to acquired cholestasis may differ considerably by ethnicity.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Povo Asiático/genética , Colestase/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Linhagem Celular , Colestase/induzido quimicamente , Cães , Feminino , Frequência do Gene/genética , Genótipo , Antígeno HLA-A2/genética , Humanos , Células Madin Darby de Rim Canino , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Hepatol Res ; 45(3): 349-55, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24739014

RESUMO

We present the case of a 25-year-old woman at 16 weeks of gestation who presented with non-comatose autoimmune acute liver failure and was at high risk of developing fulminant hepatitis. Predictive formulas indicated a high probability of developing fulminant hepatitis. Unenhanced computed tomography showed marked hepatic atrophy and broadly heterogeneous hypoattenuating areas. The course of her illness was subacute, and the etiology of liver injury was unclear. Considering all of the above, we predicted a poor prognosis. Plasma exchange (PE) and continuous hemodiafiltration (CHDF) therapy were initiated just after admission. A few days after admission, a high titer (×80) of antinuclear antibody was noted. Because autoimmune hepatitis (AIH) was considered a cause of liver failure, treatment with moderate prednisolone (30 mg/day) doses was administrated, with careful consideration of her pregnancy. Thereafter, her laboratory findings and clinical course gradually improved without the need for liver transplantation. A liver biopsy at 18 days after admission indicated a diagnosis of AIH. She continued the pregnancy and delivered a healthy baby without any complications. Eventually, prednisolone doses were decreased to 10 mg, after which her liver function worsened. The second liver biopsy also indicated a diagnosis of AIH. Accordingly, low-dose prednisolone and azathioprine doses (50 mg/day) were administrated to recover her liver function, after which her liver function regained normalcy. This case illustrates that a pregnant woman with non-comatose autoimmune acute liver failure in the first or second trimester of pregnancy and her fetus can be rescued by PE/CHDF therapy and safe moderate doses of prednisolone.

17.
Pediatr Radiol ; 45(5): 658-66, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25501257

RESUMO

BACKGROUND: Living donor liver transplantation in children often results in venous complications, leading to portal hypertension. Spleen stiffness measurements have been recently proposed as a new, noninvasive parameter for portal hypertension in cirrhotic patients. OBJECTIVE: To evaluate the diagnostic value of spleen stiffness measurements by acoustic radiation force impulse (ARFI) imaging in diagnosing venous complications after pediatric living donor liver transplantation. MATERIALS AND METHODS: We prospectively enrolled 69 patients after pediatric living donor liver transplantation using a left-side liver allograft. Around the time of the protocol liver biopsy examination, spleen stiffness measurements by ARFI imaging were performed via the left intercostal space at the center of the spleen parenchyma and repeated five times. Imaging examinations around the time of the spleen stiffness measurements were retrospectively reviewed. Regarding venous complications, significant portal and hepatic venous stenosis was defined as >50% stenosis on multiphasic computed tomography. RESULTS: After post hoc exclusion, 62 patients were studied. Portal and hepatic venous stenosis was identified in three and two patients, respectively. The median spleen stiffness values were 2.70 and 4.00 m/s in patients without and with venous complications, respectively (P < 0.001). Spleen stiffness measurements showed good diagnostic power for venous complications, and the cutoff value was determined as 2.93 m/s, with 100% sensitivity and 78.9% specificity. Spleen stiffness measurements decreased with the relief of venous stenosis resulting from an interventional radiology procedure. CONCLUSION: Spleen stiffness measurements by ARFI imaging might provide a useful quantitative index for venous complications after pediatric living donor liver transplantation.


Assuntos
Técnicas de Imagem por Elasticidade , Hipertensão Portal/diagnóstico por imagem , Transplante de Fígado , Complicações Pós-Operatórias/diagnóstico por imagem , Baço/diagnóstico por imagem , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Hipertensão Portal/fisiopatologia , Doadores Vivos , Masculino , Complicações Pós-Operatórias/fisiopatologia , Estudos Prospectivos , Sensibilidade e Especificidade , Baço/patologia
18.
Cancer Sci ; 105(10): 1254-60, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25117675

RESUMO

Non-alcoholic steatohepatitis (NASH) has emerged as a common cause of chronic liver disease and virus-independent hepatocellular carcinoma (HCC) in patients with obesity, diabetes, and metabolic syndrome. To reveal the molecular mechanism underlying hepatocarcinogenesis from NASH, microRNA (miRNA) expression profiles were analyzed in STAM mice, a NASH-HCC animal model. MicroRNA expression was also examined in 42 clinical samples of HCC tissue. Histopathological images of the liver of STAM mice at the ages of 6, 8, 12, and 18 weeks showed findings compatible with fatty liver, NASH, liver cirrhosis (LC), and HCC, respectively. Expression of miR-122 in non-tumor LC at the age of 18 weeks was significantly lower than that in LC at the age of 12 weeks. Expression of miR-122 was further decreased in HCCs relative to non-tumor LC at the age of 18 weeks. Expression of miR-122 was also decreased in clinical samples of liver tissue showing macrovesicular steatosis and HCC, being consistent with the findings in the NASH model mice. DNA methylation analysis revealed that silencing of miR-122 was not mediated by DNA hypermethylation of the promoter region. These results suggest that silencing of miR-122 is an early event during hepatocarcinogenesis from NASH, and that miR-122 could be a novel molecular marker for evaluating the risk of HCC in patients with NASH.


Assuntos
Carcinoma Hepatocelular/etiologia , Inativação Gênica , Neoplasias Hepáticas/etiologia , MicroRNAs/genética , Hepatopatia Gordurosa não Alcoólica/complicações , Animais , Sequência de Bases , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Metilação de DNA , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Masculino , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Regiões Promotoras Genéticas
19.
J Hepatol ; 60(6): 1242-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24548530

RESUMO

BACKGROUND & AIMS: Although liver fibrosis is an important predictor of outcomes for biliary atresia (BA), postsurgical native liver histology has not been well reported. Here, we retrospectively evaluated postsurgical native liver histology, and developed and assessed a novel scoring system - the BA liver fibrosis (BALF) score for non-invasively predicting liver fibrosis grades. METHODS: We identified 259 native liver specimens from 91 BA patients. Of these, 180 specimens, obtained from 62 patients aged ≥1 year at examination, were used to develop the BALF scoring system. The BALF score equation was determined according to the prediction of histological fibrosis grades by multivariate ordered logistic regression analysis. The diagnostic powers of the BALF score and several non-invasive markers were assessed by area under the receiver operating characteristic curve (AUROC) analyses. RESULTS: Natural logarithms of the serum total bilirubin, γ-glutamyltransferase, and albumin levels, and age were selected as significantly independent variables for the BALF score equation. The BALF score had a good diagnostic power (AUROCs=0.86-0.94, p<0.001) and good diagnostic accuracy (79.4-93.3%) for each fibrosis grade. The BALF score revealed a strong correlation with fibrosis grade (r=0.77, p<0.001), and was the preferable non-invasive marker for diagnosing fibrosis grades ⩾F2. In a serial liver histology subgroup analysis, 7/15 patients exhibited liver fibrosis improvement with BALF scores being equivalent to histological fibrosis grades of F0-1. CONCLUSIONS: In postsurgical BA patients aged ⩾1year, the BALF score is a potential non-invasive marker of native liver fibrosis.


Assuntos
Atresia Biliar/patologia , Atresia Biliar/cirurgia , Cirrose Hepática/patologia , Cirrose Hepática/cirurgia , Portoenterostomia Hepática , Índice de Gravidade de Doença , Adolescente , Biomarcadores/sangue , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Testes de Função Hepática , Modelos Logísticos , Masculino , Modelos Biológicos , Análise Multivariada , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos
20.
J Hepatol ; 61(1): 98-106, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24657401

RESUMO

BACKGROUND & AIMS: Acyl-coenzyme A: cholesterol acyltransferase (ACAT) catalyzes the conversion of free cholesterol (FC) to cholesterol ester, which prevents excess accumulation of FC. We recently found that FC accumulation in hepatic stellate cells (HSCs) plays a role in progression of liver fibrosis, but the effect of ACAT1 on liver fibrosis has not been clarified. In this study, we aimed to define the role of ACAT1 in the pathogenesis of liver fibrosis. METHODS: ACAT1-deficient and wild-type mice, or Toll-like receptor 4 (TLR4)(-/-)ACAT1(+/+) and TLR4(-/-)ACAT1(-/-) mice were subjected to bile duct ligation (BDL) for 3 weeks or were given carbon tetrachloride (CCl4) for 4 weeks to induce liver fibrosis. RESULTS: ACAT1 was the major isozyme in mice and human primary HSCs, and ACAT2 was the major isozyme in mouse primary hepatocytes and Kupffer cells. ACAT1 deficiency significantly exaggerated liver fibrosis in the mouse models of liver fibrosis, without affecting the degree of hepatocellular injury or liver inflammation, including hepatocyte apoptosis or Kupffer cell activation. ACAT1 deficiency significantly increased FC levels in HSCs, augmenting TLR4 protein and downregulating expression of transforming growth factor-ß (TGFß) pseudoreceptor Bambi (bone morphogenetic protein and activin membrane-bound inhibitor), leading to sensitization of HSCs to TGFß activation. Exacerbation of liver fibrosis by ACAT1 deficiency was dependent on FC accumulation-induced enhancement of TLR4 signaling. CONCLUSIONS: ACAT1 deficiency exaggerates liver fibrosis mainly through enhanced FC accumulation in HSCs. Regulation of ACAT1 activities in HSCs could be a target for treatment of liver fibrosis.


Assuntos
Colesterol/metabolismo , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/metabolismo , Esterol O-Aciltransferase/metabolismo , Animais , Células Cultivadas , Ésteres do Colesterol/metabolismo , Progressão da Doença , Células Estreladas do Fígado/patologia , Humanos , Células de Kupffer/metabolismo , Células de Kupffer/patologia , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais , Esterol O-Aciltransferase/deficiência , Esterol O-Aciltransferase/genética , Receptor 4 Toll-Like/deficiência , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fator de Crescimento Transformador beta/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA