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1.
Eur J Pharmacol ; 921: 174866, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35231468

RESUMO

The proliferation of hepatic progenitor cells (HPCs) contributes to liver regeneration and fibrogenesis during chronic liver injury; however, the mechanism modulating HPC proliferation remains unknown. Y-box binding protein-1 (YB-1) is a transcription factor that regulates the transcription of several genes and is highly expressed in liver injury. We explored the role of YB-1 in HPC proliferation and liver fibrosis. We detected increased expansion of HPCs and elevated levels of YB-1 in HPCs from patients with hepatitis B virus-related fibrosis and choline-deficient ethionine-supplemented or 5-diethoxycarbonyl-1,4-dihydrocollidine diet-induced mice compared with those in control groups. HPC-specific deletion of YB-1 using YB-1flox/flox; Foxl1-Cre+/- mice led to reduced HPC expansion and less collagen deposition in the liver tissues compared with that in Cre-/- mice. In cultured primary HPCs, YB-1 knockdown inhibited HPC proliferation. Further experiments indicated YB-1 negatively regulated p53 expression, and silencing of p53 blocked YB-1 knockdown-mediated inhibition of HPC proliferation. Collectively, YB-1 negatively regulates HPC proliferation and alleviates liver fibrosis by p53.


Assuntos
Cirrose Hepática , Células-Tronco , Fatores de Transcrição/metabolismo , Proteína 1 de Ligação a Y-Box/metabolismo , Animais , Proliferação de Células/genética , Etionina/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Humanos , Fígado/metabolismo , Cirrose Hepática/patologia , Regeneração Hepática/genética , Camundongos , Células-Tronco/metabolismo
2.
Biochem Biophys Res Commun ; 506(1): 12-19, 2018 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-30333090

RESUMO

Although the regeneration of the adult liver depends on hepatic progenitor cells (HPCs), many uncertainties regarding hepatic regeneration in the injured liver remain. Trefoil factor family 1 (TFF1), a secretory protein predominantly expressed in the gastrointestinal tract, is responsible for mucosal restitution. Here, we investigated the role of TFF1 in liver regeneration using a mouse model of hepatic injury (choline-deficient ethionine-supplemented diet and carbon tetrachloride administration) and genetically engineered mice (TFF1 knockout (TFF1-/-)). Immunohistochemistry analysis of human liver samples revealed TFF1 expression in the hepatocytes close to ductular reaction and the regenerating biliary epithelium in injured liver. The number of cytokeratin 19 (CK19)-positive bile ducts was significantly decreased in the TFF1-/- mice after liver injury. Notch pathway in the TFF1-/- mice was also downregulated. HPCs in the control mice differentiated into biliary cells (CK19+/SRY HMG box 9 (SOX9)+) more frequently. In contrast, HPCs in the TFF1-/- mice more frequently differentiated into a hepatic lineage (alpha fetoprotein+/SOX9+) after acute liver damage. Hepatocyte proliferation was upregulated, and the liver weight was increased in TFF1-/- mice in response to chronic liver damage. Thus, TFF1 is responsible for liver regeneration after liver injury by promoting HPC differentiation into a biliary lineage and inhibiting HPC differentiation into a hepatic lineage.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/genética , Hepatócitos/metabolismo , Regeneração Hepática/genética , Células-Tronco/metabolismo , Fator Trefoil-1/genética , Animais , Ductos Biliares/citologia , Ductos Biliares/efeitos dos fármacos , Ductos Biliares/metabolismo , Tetracloreto de Carbono/administração & dosagem , Carcinógenos/administração & dosagem , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/secundário , Diferenciação Celular , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Deficiência de Colina/genética , Deficiência de Colina/metabolismo , Deficiência de Colina/patologia , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Dieta/efeitos adversos , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Etionina/administração & dosagem , Regulação da Expressão Gênica , Hepatite Crônica/genética , Hepatite Crônica/metabolismo , Hepatite Crônica/patologia , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Humanos , Queratina-19/genética , Queratina-19/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Regeneração Hepática/efeitos dos fármacos , Camundongos , Camundongos Knockout , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Transdução de Sinais , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Fator Trefoil-1/deficiência
3.
Mol Med Rep ; 17(3): 3905-3911, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29286119

RESUMO

The present study aimed to observe the effects of perioperative oral supplementation with fish oil (FO) on liver regeneration in mice and examine the potential mechanism. A total of 120 male ICR mice were randomly divided into 5 groups: Sham, Control, fish oil (FO), Compound C [the AMP­activated protein kinase (AMPK) inhibitor dorsomorphin], and Compound C + FO. Changes in liver function, alterations in hepatocyte proliferation and in the expression of polarization markers, and activation of AMPK signaling were examined following partial hepatectomy (PH). The results demonstrated that restoration of serum alanine aminotransferase (ALT) and total bilirubin (TBIL) levels were significantly faster in FO­treated mice compared with Control mice, and this effect was suppressed by treatment with Compound C. FO­treated mice exhibited increased numbers of Ki­67 positive hepatocytes and their postoperative liver­to­body weight ratio was significantly increased compared with the Control mice, which was also suppressed by co­treatment with the AMPK inhibitor. Furthermore, protein expression of Occludin, Claudin­3, tight junction protein 1 and bile salt export pump was gradually increased in FO­treated mice compared with Control, whereas Compound C treatment reversed this effect. Therefore, the present study revealed that perioperative oral supplementation with FO may promote liver regeneration and improved liver function in mice following PH through AMPK activation.


Assuntos
Proteínas Quinases Ativadas por AMP/genética , Óleos de Peixe/farmacologia , Hepatectomia/reabilitação , Regeneração Hepática/efeitos dos fármacos , Fígado/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP/metabolismo , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/genética , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/metabolismo , Administração Oral , Alanina Transaminase/sangue , Alanina Transaminase/genética , Animais , Bilirrubina/sangue , Proliferação de Células/efeitos dos fármacos , Claudina-3/genética , Claudina-3/metabolismo , Óleos de Peixe/antagonistas & inibidores , Regulação da Expressão Gênica , Hepatectomia/métodos , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Fígado/metabolismo , Fígado/cirurgia , Testes de Função Hepática , Regeneração Hepática/genética , Masculino , Camundongos , Camundongos Endogâmicos ICR , Ocludina/genética , Ocludina/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais , Proteína da Zônula de Oclusão-1/genética , Proteína da Zônula de Oclusão-1/metabolismo
4.
Arq Bras Cir Dig ; 30(2): 122-126, 2017.
Artigo em Inglês, Português | MEDLINE | ID: mdl-29257848

RESUMO

BACKGROUND: Partial hepatectomy is a surgical intervention of the liver that can trigger its regenerative process, where the residual lobes deflagrate a compensatory hyperplasia, causing its restoration almost to the original volume. Nevertheless, depending on the extent of liver damage its regeneration might be impaired. The low-power laser has been studied with beneficial results. AIM: To investigate the possible functional and mutagenic damage arising from the use of low-power laser used in liver regeneration after partial hepatectomy. METHODS: Fifteen male adult Wistar rats were hepatectomizated in 70% and laser irradiated or not with dose of 70 J/cm2, 650 nm, 100 mW, directly on the remaining liver, during the perioperative period. These animals were divided into four groups: G1 (control, 7 days); G2 (laser, 7 days); G3 (control, 14 days); G4 (laser, 14 days). Were analyzed the liver weight; number of hepatocytes; deposition of collagen fibers; liver function tests: serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma glutamyl transferase, bilirubin and micronucleus test in peripheral blood erythrocyte. RESULTS: The liver weight was greater in G3 and G4 (p=0.001 and p=0.002) compared to other groups. The deposition of collagen fibers in G1 was statistically higher than the other groups (p=0.01). In tests of liver function and micronucleus test was not found significant differences between the studied groups. CONCLUSION: Low-power laser stimulation did not cause loss of liver function or mutagenic damage.


Assuntos
Hepatectomia/métodos , Regeneração Hepática/efeitos da radiação , Terapia com Luz de Baixa Intensidade , Animais , Regeneração Hepática/genética , Regeneração Hepática/fisiologia , Terapia com Luz de Baixa Intensidade/efeitos adversos , Masculino , Mutação , Ratos , Ratos Wistar
5.
Exp Mol Med ; 49(9): e380, 2017 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-28935975

RESUMO

Tumor necrosis factor-inducible gene 6 protein (TSG-6) has recently been shown to protect the liver from acute damage. However, the mechanism underlying the effect of TSG-6 on the liver remains unclear. Autophagy is a catabolic process that targets cell components to lysosomes for degradation, and its functions are reported to be dysregulated in liver diseases. Here we investigate whether TSG-6 promotes liver regeneration by inducing autophagic clearance in damaged livers. Mice fed a methionine choline-deficient diet supplemented with 0.1% ethionine (MCDE) for 2 weeks were injected with TSG-6 (the M+TSG-6 group) or saline (the M+V group) and fed with MCDE for 2 additional weeks. Histomorphological evidence of injury and increased levels of liver enzymes were evident in MCDE-treated mice, whereas these symptoms were ameliorated in the M+TSG-6 group. Livers from this group contained less active caspase-3 and more Ki67-positive hepatocytic cells than the M+V group. The autophagy markers ATG3, ATG7, LC3-II, LAMP2A and RAB7 were elevated in the M+TSG-6 group compared with those in the M+V group. Immunostaining for LC3 and RAB7 and electron microscopy analysis showed the accumulation of autophagy structures in the M+TSG-6 group. TSG-6 also blocked both tunicamycin- and palmitate-induced apoptosis of hepatocytes and increased their viability by inducing autophagy formation in these cells. An autophagy inhibitor suppressed TSG-6-mediated autophagy in the injured hepatocytes and livers of MCDE-treated mice. These results therefore demonstrate that TSG-6 protects hepatocytes from damage by enhancing autophagy influx and contributes to liver regeneration, suggesting that TSG-6 has therapeutic potential for the treatment of liver diseases.


Assuntos
Autofagia/genética , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Hepatopatias/genética , Hepatopatias/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular/genética , Doença Crônica , Modelos Animais de Doenças , Hepatócitos/metabolismo , Hepatócitos/patologia , Hepatócitos/ultraestrutura , Hepatopatias/mortalidade , Hepatopatias/patologia , Regeneração Hepática/genética , Masculino , Camundongos
6.
HPB (Oxford) ; 19(12): 1091-1103, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28941575

RESUMO

BACKGROUND: The Associating Liver Partition and Portal Ligation for Staged Hepatectomy (ALPPS) depends on a significant inter-stages kinetic growth rate (KGR). Liver regeneration is highly energy-dependent. The metabolic adaptations in ALPPS are unknown. AIMS: i) Assess bioenergetics in both stages of ALPPS (T1 and T2) and compare them with control patients undergoing minor (miHp) and major hepatectomy (MaHp), respectively; ii) Correlate findings in ALPPS with volumetric data; iii) Investigate expression of genes involved in liver regeneration and energy metabolism. METHODS: Five patients undergoing ALPPS, five controls undergoing miHp and five undergoing MaHp. Assessment of remnant liver bioenergetics in T1, T2 and controls. Analysis of gene expression and protein content in ALPPS. RESULTS: Mitochondrial function was worsened in T1 versus miHp; and in T2 versus MaHp (p < 0.05); but improved from T1 to T2 (p < 0.05). Liver bioenergetics in T1 strongly correlated with KGR (p < 0.01). An increased expression of genes associated with liver regeneration (STAT3, ALR) and energy metabolism (PGC-1α, COX, Nampt) was found in T2 (p < 0.05). CONCLUSION: Metabolic capacity in ALPPS is worse than in controls, improves between stages and correlates with volumetric growth. Bioenergetic adaptations in ALPPS could serve as surrogate markers of liver reserve and as target for energetic conditioning.


Assuntos
Metabolismo Energético , Hepatectomia/métodos , Regeneração Hepática , Fígado/cirurgia , Mitocôndrias Hepáticas/metabolismo , Veia Porta/cirurgia , Idoso , Estudos de Casos e Controles , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 1/metabolismo , Redutases do Citocromo/genética , Redutases do Citocromo/metabolismo , Citocinas/genética , Citocinas/metabolismo , Metabolismo Energético/genética , Feminino , Regulação da Expressão Gênica , Hepatectomia/efeitos adversos , Humanos , Ligadura , Fígado/metabolismo , Fígado/patologia , Regeneração Hepática/genética , Masculino , Pessoa de Meia-Idade , Nicotinamida Fosforribosiltransferase/genética , Nicotinamida Fosforribosiltransferase/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo Enxofre , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Fatores de Tempo , Resultado do Tratamento
7.
ABCD (São Paulo, Impr.) ; 30(2): 122-126, Apr.-June 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-885715

RESUMO

ABSTRACT Background: Partial hepatectomy is a surgical intervention of the liver that can trigger its regenerative process, where the residual lobes deflagrate a compensatory hyperplasia, causing its restoration almost to the original volume. Nevertheless, depending on the extent of liver damage its regeneration might be impaired. The low-power laser has been studied with beneficial results. Aim: To investigate the possible functional and mutagenic damage arising from the use of low-power laser used in liver regeneration after partial hepatectomy. Methods: Fifteen male adult Wistar rats were hepatectomizated in 70% and laser irradiated or not with dose of 70 J/cm2, 650 nm, 100 mW, directly on the remaining liver, during the perioperative period. These animals were divided into four groups: G1 (control, 7 days); G2 (laser, 7 days); G3 (control, 14 days); G4 (laser, 14 days). Were analyzed the liver weight; number of hepatocytes; deposition of collagen fibers; liver function tests: serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma glutamyl transferase, bilirubin and micronucleus test in peripheral blood erythrocyte. Results: The liver weight was greater in G3 and G4 (p=0.001 and p=0.002) compared to other groups. The deposition of collagen fibers in G1 was statistically higher than the other groups (p=0.01). In tests of liver function and micronucleus test was not found significant differences between the studied groups. Conclusion: Low-power laser stimulation did not cause loss of liver function or mutagenic damage.


RESUMO Racional: A hepatectomia parcial é intervenção cirúrgica que pode desencadear processo regenerativo, onde os lobos residuais deflagram resposta de hiperplasia compensatória, ocasionando restauração próxima ao seu volume original. Contudo, dependendo da extensão das lesões hepáticas a regeneração pode ser prejudicada. O laser de baixa potência tem sido pesquisado com resultados benéficos no processo de regeneração hepática. Objetivo: Investigar os possíveis danos funcionais e mutagênicos decorrentes da utilização do laser de baixa potência utilizado na regeneração hepática após hepatectomia parcial. Métodos: Quinze ratos adultos Wistar foram hepatectomizados a 70%, irradiados ou não com laser, dose de 70 J/cm2, 650 nm,100 mW, de forma direta sobre o fígado remanescente, durante o período transoperatório. Os animais foram distribuídos em quatro grupos: G1 (controle, 7 dias); G2 (laser, 7 dias); G3 (controle 14 dias); G4 (laser,14 dias). Foram analisados o peso do fígado; número de hepatócitos; deposição de fibras colágenas; teste de função hepática: alanina aminotransferase, aspartato aminotransferase, fosfatase alcalina, gama glutamiltransferase, bilirrubinas e teste de micronúcleo em eritrócitos. Resultados: O peso do fígado apresentou-se aumentado nos grupos G3 e G4 (p=0,001 e p=0,002) comparados aos demais grupos. A deposição das fibras colágenas no G1 foi estatisticamente maior em relação aos demais grupos (p=0,01). Nos testes de função hepática e teste de micronúcleo não foram encontradas diferenças significativas entre os grupos. Conclusão: O laser de baixa potência não ocasionou perda de função hepática ou dano mutagênico.


Assuntos
Animais , Masculino , Ratos , Terapia com Luz de Baixa Intensidade/efeitos adversos , Hepatectomia/métodos , Regeneração Hepática/efeitos da radiação , Ratos Wistar , Regeneração Hepática/fisiologia , Regeneração Hepática/genética , Mutação
8.
J Toxicol Sci ; 41(1): 165-73, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26763404

RESUMO

Tripterygium glycosides (TG) are commonly used for basic medicine in curing rheumatoid arthritis but with a high incidence of liver injury. Geniposide (GP) has broad and diverse bioactivities, but until now it is still unknown whether GP can protect against TG-induced liver injury. This study, for the first time, observed the possible protection of GP against TG-induced liver injury in mice and its mechanisms underlying. Oral administration of TG (270 mg/kg) induced significant elevation in the levels of serum alanine / aspartate transaminase (ALT/AST), hepatic malondialdehyde (MDA) and pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-α) (all P < 0.01). On the other hand, remarkably decreased biomarkers, including hepatic glutathione (GSH) level, activities of glutathione transferase (GST), glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT), and anti-inflammatory cytokine interleukin (IL)-10, were observed following TG exposure (all P < 0.01). Nevertheless, all of these phenotypes were evidently reversed by pre-administration of GP for 7 continuous days. Further analysis showed that the mRNA expression of hepatic growth factor-beta1 (TGF-ß1), one of tissue repair and regeneration cytokines, was enhanced by GP. Taken together, the current research suggests that GP protects against TG-induced liver injury in mice probably involved during attenuating oxidative stress and inflammation, and promoting tissue repair and regeneration.


Assuntos
Antirreumáticos/administração & dosagem , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Glicosídeos/administração & dosagem , Iridoides/administração & dosagem , Iridoides/farmacologia , Tripterygium/química , Administração Oral , Alanina Transaminase/metabolismo , Animais , Anti-Inflamatórios , Antirreumáticos/efeitos adversos , Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Glicosídeos/efeitos adversos , Fígado/metabolismo , Regeneração Hepática/genética , Masculino , Camundongos Endogâmicos , Estresse Oxidativo/efeitos dos fármacos , Fitoterapia , RNA Mensageiro/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
9.
J Gastroenterol Hepatol ; 29(3): 603-13, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23981054

RESUMO

BACKGROUND AND AIM: Acute liver injury is manifested by different degree of hepatocyte necrosis and may recover via the process of hepatocyte regeneration once the injury is discontinued. Most of the liver injury is associating with inflammatory cytokines. Resveratrol (RSV) is a natural phytoalexin with powerful anti-inflammatory effects. AIM: The effects of RSV on cellular factors mediating liver damage and regeneration in acute carbon tetrachloride (CCl4 ) liver injury were investigated. RESULTS: RSV decreased alanine aminotransferase, aspartate aminotransferase, necrosis, and 4-hydroxynonenal in the CCl4 -injured liver. RSV decreased hepatocyte apoptosis by reducing caspase 8 and caspase 3 but not Bax and Bcl-xL. RSV reduced Kupffer cells recruitment, the expressions of tumor necrosis factor-α and interleukin-6, but not interleukin-10. RSV lowered the numbers of anti-5-bromon-2'-deoxyuridine and anti-Ki67-positive hepatocytes. Hepatic hepatocyte growth factor, c-Met and transforming growth factor-α expressions were reduced by RSV, while transforming growth factor-ß1 and hepatic stellate cells activation were not changed. RSV reduced the injury-induced CXCL10 elevations in serum and liver in vivo. Besides, RSV inhibited CXCL10 release from CCl4 -injured hepatocytes in vitro. In contrast, recombinant CXCL10 improved the viability of CCl4 -injured hepatocytes. CONCLUSIONS: RSV therapy can be beneficial for acute toxic liver injury. RSV reduced hepatocyte apoptosis but limited hepatocyte regeneration possibly through reducing the hepatomitogenic signaling and the release of CXCL10.


Assuntos
Anti-Inflamatórios , Apoptose/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Quimiocina CXCL10/metabolismo , Hepatócitos/metabolismo , Regeneração Hepática/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/fisiopatologia , Fitoterapia , Estilbenos/farmacologia , Estilbenos/uso terapêutico , Alanina Transaminase/metabolismo , Aldeídos/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Tetracloreto de Carbono , Caspase 3/metabolismo , Caspase 8/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/patologia , Citocinas/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Mediadores da Inflamação/metabolismo , Fígado/patologia , Regeneração Hepática/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Necrose/tratamento farmacológico , Resveratrol , Sesquiterpenos , Fitoalexinas
10.
J Zhejiang Univ Sci B ; 13(9): 695-706, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22949360

RESUMO

BACKGROUND AND OBJECTIVE: Liver regeneration is a complex process regulated by a group of genetic and epigenetic factors. A variety of genetic factors have been reported, whereas few investigations have focused on epigenetic regulation during liver regeneration. In the present study, valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, was used to investigate the effect of HDAC on liver regeneration. METHODS: VPA was administered via intraperitoneal injection to 2/3 partially hepatectomized mice to detect hepatocyte proliferation during liver regeneration. The mice were sacrificed, and their liver tissues were harvested at sequential time points from 0 to 168 h after treatment. DNA synthesis was detected via a BrdU assay, and cell proliferation was tested using Ki-67. The expressions of cyclin D1, cyclin E, cyclin dependent kinase 2 (CDK2), and CDK4 were detected by Western blot analysis. Chromatin immunoprecipitation (ChIP) assay was used to examine the recruitment of HDACs to the target promoter regions and the expression of the target gene was detected by Western blot. RESULTS: Immunohistochemical analysis showed that cells positive for BrdU and Ki-67 decreased, and the peak of BrdU was delayed in the VPA-administered mice. Consistently, cyclin D1 expression was also delayed. We identified B-myc as a target gene of HDACs by complementary DNA (cDNA) microarray. The expression of B-myc increased in the VPA-administered mice after hepatectomy (PH). The ChIP assay confirmed the presence of HDACs at the B-myc promoter. CONCLUSIONS: HDAC activities are essential for liver regeneration. Inhibiting HDAC activities delays liver regeneration and induces liver cell cycle arrest, thereby causing an anti-proliferative effect on liver regeneration.


Assuntos
Inibidores de Histona Desacetilases/farmacologia , Regeneração Hepática/efeitos dos fármacos , Ácido Valproico/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Ciclinas/antagonistas & inibidores , Epigênese Genética/efeitos dos fármacos , Hepatectomia , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/fisiologia , Histona Desacetilases/fisiologia , Regeneração Hepática/genética , Regeneração Hepática/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-myc/genética , Transcrição Gênica/efeitos dos fármacos
11.
Gene Expr Patterns ; 11(3-4): 255-62, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21216305

RESUMO

We have previously identified Epiplakin1 (Eppk1) as a gene expressed in pancreatic progenitor cells. Here we studied the expression of Eppk1 in developing and regenerating livers in mice. Eppk1 is initially expressed in the early bipotential hepatoblasts and is later confined to the cholangiocytes. After birth, Eppk1 is expressed in the bile duct. In the livers of mice fed with a choline-deficient ethionine-supplemented (CDE) diet, Eppk1-positive cells dramatically increase in number. The Eppk1-positive cells express A6, thereby indicating that they are hepatic progenitor cells. Other cholangiocyte markers, such as Cytokeratins, E-cadherin, osteopontin and Sox9, are also co-expressed in the hepatic progenitor cells. Some of the Eppk1-positive cells express PCNA, a proliferation marker, thereby suggesting their identities as transient amplifying cells. In conclusion, we have shown that Eppk1 serves as a useful marker for detecting the hepatic progenitor population in the developing and adult liver. The use of Eppk1 as a marker will facilitate studies of mouse hepatic progenitor cells.


Assuntos
Antígenos de Diferenciação/metabolismo , Autoantígenos/metabolismo , Ductos Biliares/metabolismo , Fígado/citologia , Células-Tronco/metabolismo , Células-Tronco Adultas/citologia , Células-Tronco Adultas/metabolismo , Animais , Ductos Biliares/citologia , Caderinas/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Linhagem da Célula , Epitélio/metabolismo , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Fígado/embriologia , Fígado/lesões , Regeneração Hepática/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Serrate-Jagged , Células-Tronco/citologia
12.
Biochem Biophys Res Commun ; 342(2): 434-40, 2006 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-16487486

RESUMO

Several recent studies have reported that bone marrow cells (BMCs) have the ability to generate functional hepatocytes. However, the efficiency at which BMC transplantation generates functional hepatocytes is rather low. We assumed that if BMCs accumulated directly in liver, the functional BMC-derived hepatocytes should increase efficiently. We tried to increase the accumulation of BMCs directly in liver through the interaction between hepatic asialoglycoprotein receptor and desialylated BMCs. Desialylated BMCs were produced with treatment of neuraminidase. Desialylated BMCs that expressed green fluorescent protein (GFP) were injected into Long Evans Cinnamon (LEC) rats, a human Wilson's disease model, intravenously. At 3 and 5 months after transplantation, GFP-expressing hepatocyte nodules appeared in the liver of these BMC-transplanted LEC rats. These findings suggest that the functional BMC-derived hepatocytes can be generated by the direct accumulation of BMCs and that this strategy is new BMC therapy for liver regeneration.


Assuntos
Células da Medula Óssea/metabolismo , Transplante de Medula Óssea , Glicosídeos/metabolismo , Hepatopatias/terapia , Regeneração Hepática/fisiologia , Animais , Animais Geneticamente Modificados , Receptor de Asialoglicoproteína/fisiologia , Células Cultivadas , Técnicas de Cocultura , Galactose/biossíntese , Genes Reporter , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Hepatócitos/metabolismo , Imuno-Histoquímica , Regeneração Hepática/genética , Masculino , Neuraminidase/farmacologia , Ratos , Ratos Endogâmicos LEC , Ratos Wistar
13.
Int J Mol Med ; 16(2): 221-31, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16012753

RESUMO

The aim of this study was to demonstrate that regenerating liver responses to a herbal remedy could be presented by gene expression profiling. Compositions of the ingredients in the remedy containing Scutellaria baicalensis Georgi and Bupleurum scorzonerifolfium Wild (S/B remedy) were analyzed and quantified by high performance liquid chromatography. By using a 70% partial hepatectomy in BALB/c mice as an in vivo model, the effects of high dose (50 mg/kg) and low dose (1 mg/kg) S/B remedy were evaluated by cDNA microarray, followed by RT-PCR and real-time PCR confirmation. Factors affecting proliferative activities of mouse hepatocytes were measured by DNA flow cytometry, BrdU incorporation assay and serum interleukin-6 (IL-6) level. Based on global gene expression profiles, the results showed that the low dose S/B remedy down-regulated expression of immediate early genes and cell cycle-related genes, whereas the high dose had opposite effects. The gene expression was further verified by real-time RT-PCR. Proliferative activities, in terms of synthetic phase fractions and G2/M phase fractions, in vehicle, low dose, and high dose groups were 18.45+/-2.56%, 14.65+/-1.06%; 9.27+/-0.85%, 7.80+/-0.11%; and 18.90+/-2.17%, 22.95+/-0.25%, respectively. The serum IL-6 level was also dose-dependent in both low and high dose S/B remedy-treated mice. We conclude that in vivo gene expression profiling correlates with liver responses to a herbal remedy, which provides a new direction for pharmaceutical studies on human diseases.


Assuntos
Perfilação da Expressão Gênica , Fígado/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Bromodesoxiuridina/metabolismo , Bupleurum/química , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , DNA/análise , DNA/genética , Relação Dose-Resposta a Droga , Citometria de Fluxo , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatectomia/métodos , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Interleucina-6/sangue , Fígado/metabolismo , Fígado/cirurgia , Regeneração Hepática/efeitos dos fármacos , Regeneração Hepática/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Extratos Vegetais/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Scutellaria baicalensis/química , Fatores de Tempo
14.
Gene ; 319: 85-97, 2003 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-14597174

RESUMO

The eukaryotic trifunctional enzyme, C(1)-tetrahydrofolate (THF) synthase, interconverts folic acid derivatives between various oxidation states and is critical for normal cellular function, growth, and differentiation. Using a rat C(1)-THF synthase cDNA and synthetic oligonucleotides, the rat C(1)-THF synthase gene was isolated and characterized. The gene consists of 28 exons and spans 67.5 kbp. Primer extension, RNase protection, and rapid amplification of cDNA ends (RACE) experiments indicate the presence of multiple transcription start points (tsp) within a 250-bp window located between 50 and 300 bp upstream from the start codon. The 5' flanking region is devoid of a TATA consensus sequence motif, but putative regulatory elements, including NF-kappabeta, HNF-4alpha1, RARalpha1, C/EBP, and PPAR are present in the promoter region. The 5' flanking region also contains two sets of tetranucleotide repeats and two short interspersed nuclear elements (SINES). The initial 2500 bp of 5' flanking sequences of the rat and mouse cytoplasmic C(1)-THF synthase genes share 70% identity. However, comparison with the human gene from the Human Genome Data Bank revealed no significant homology in the 5' flanking region. The gene structure characterization led to the identification of a pseudogene that is 94% identical to the C(1)-THF synthase gene and probably diverged 10-12 million years ago. In addition, the gene expression patterns of C(1)-THF synthase were investigated during liver regeneration and liver and kidney organogenesis, two highly regulated events. In both processes, C(1)-THF synthase expression correlated with increased nucleotide metabolism. This pattern suggests that the gene is regulated in response to changes in the demand for folate-dependent one-carbon units.


Assuntos
Aminoidrolases/genética , Desenvolvimento Embrionário e Fetal/genética , Formiato-Tetra-Hidrofolato Ligase/genética , Regeneração Hepática/genética , Metilenotetra-Hidrofolato Desidrogenase (NADP)/genética , Complexos Multienzimáticos/genética , Região 5'-Flanqueadora/genética , Animais , Animais Recém-Nascidos , Sequência de Bases , Citoplasma/enzimologia , DNA/química , DNA/genética , DNA Complementar/química , DNA Complementar/genética , Éxons , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Genes/genética , Íntrons , Masculino , Dados de Sequência Molecular , Gravidez , Regiões Promotoras Genéticas/genética , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Fatores de Tempo , Sítio de Iniciação de Transcrição , Transcrição Gênica
15.
J Biol Chem ; 273(52): 35208-15, 1998 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-9857059

RESUMO

Arg-Ser-rich domain-containing proteins (SR proteins), a family of splicing factors, can regulate pre-mRNA alternative splicing in a concentration dependent manner. Thus, the relative expression of various SR proteins may play an important role in alternative splicing regulation. HRS/SRp40, an SR protein and delayed early gene in liver regeneration, can mediate alternative splicing of fibronectin mRNA. Here we determined that transcription of the HRS/SRp40 gene is induced about 5-fold during liver regeneration, similar to the level of steady-state mRNA. We found that both mouse and human HRS promoters lack TATA and CAAT boxes. The mouse promoter region from -130 to -18, which contains highly conserved GA-binding protein (GABP) and YY1 binding sites, conferred high transcriptional activity. While GABPalpha/GABPbeta heterodimer transactivated the HRS promoter, YY1 functioned as a repressor. During liver regeneration, the relative amount of GABPalpha/GABPbeta heterodimer increased 3-fold, and YY1 changed little, which could partially account for the increase in HRS gene transcription. Interleukin-6, a critical mitogenic component of liver regeneration, was able to relieve the repressive activity of the YY1 site within the HRS promoter. The combined effect of small changes in the level of existing transcription factors and mitogenic signals may explain the transcriptional activation of the HRS gene during cell growth.


Assuntos
Processamento Alternativo , Regeneração Hepática/genética , Mitógenos/metabolismo , Proteínas Nucleares/biossíntese , Fosfoproteínas/biossíntese , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Proteínas Estimuladoras de Ligação a CCAAT , Proteínas de Ligação a DNA/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte , Fatores de Ligação de DNA Eritroide Específicos , Fator de Transcrição de Proteínas de Ligação GA , Humanos , Interleucina-6/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , Proteínas de Ligação a RNA , Ratos , Ratos Endogâmicos F344 , Deleção de Sequência , Fatores de Processamento de Serina-Arginina , Transdução de Sinais , Transcrição Gênica , Regulação para Cima , Fator de Transcrição YY1
16.
Jpn J Cancer Res ; 86(9): 811-8, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7591957

RESUMO

mRNA levels for ten protein tyrosine phosphatases (PTPs), PTP-S, PTPH1, PTP-1, GLEPP1, LRP, PTP1D, PTPG1, PTP gamma, PTP delta, and LAR, were determined during regeneration of rat liver, and mRNA levels for 5 PTPs, PTP-S, PTP-1, PTP gamma, PTP delta, and LRP, were determined in three lines of rat ascites hepatoma cells. In regenerating rat liver, the expression patterns of PTP genes after partial hepatectomy could be classified into four groups. In group 1 (PTP-S and PTPH1), the mRNA levels increased rapidly, reached a maximum 7 h after partial hepatectomy, remained at a plateau for 1-2 days and then decreased gradually. In group 2 (PTP-1, GLEPP1, and LRP), the mRNA levels showed two peaks on days 1 and 5, and then decreased gradually. In group 3 (PTP1D and PTPG1), the mRNA levels increased rapidly, reached a maximum at 7 h, remained high for several days, and then did not decrease but rather increased after day 7. In group 4 (PTP gamma, PTP delta, and LAR), the mRNA levels remained constant for the first 5 days and increased over the control levels after day 7. In rat ascites hepatomas, gene expression of non-receptor-like PTPs (PTP-S and PTP-1) showed various neoplastic alterations, whereas mRNAs of receptor-like PTPs (PTP gamma, PTP delta, and LRP) were lost or drastically decreased.


Assuntos
Neoplasias Hepáticas Experimentais/enzimologia , Regeneração Hepática/genética , Fígado/enzimologia , Proteínas Tirosina Fosfatases/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Expressão Gênica , Hepatectomia , Fígado/metabolismo , Neoplasias Hepáticas Experimentais/genética , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Homologia de Sequência de Aminoácidos , Transcrição Gênica
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