RESUMEN
Dysregulation of liver functions leads to insulin resistance causing type 2 diabetes mellitus and is often found in chronic liver diseases. However, the mechanisms of hepatic dysfunction leading to hepatic metabolic disorder are still poorly understood in chronic liver diseases. The current work investigated the role of hepatitis B virus X protein (HBx) in regulating glucose metabolism. We studied HBx-overexpressing (HBxTg) mice and HBxTg mice lacking inducible nitric oxide synthase (iNOS). Here we show that gene expressions of the key gluconeogenic enzymes were significantly increased in HepG2 cells expressing HBx (HepG2-HBx) and in non-tumor liver tissues of hepatitis B virus patients with high levels of HBx expression. In the liver of HBxTg mice, the expressions of gluconeogenic genes were also elevated, leading to hyperglycemia by increasing hepatic glucose production. However, this effect was insufficient to cause systemic insulin resistance. Importantly, the actions of HBx on hepatic glucose metabolism are thought to be mediated via iNOS signaling, as evidenced by the fact that deficiency of iNOS restored HBx-induced hyperglycemia by suppressing the gene expression of gluconeogenic enzymes. Treatment of HepG2-HBx cells with nitric oxide (NO) caused a significant increase in the expression of gluconeogenic genes, but JNK1 inhibition was completely normalized. Furthermore, hyperactivation of JNK1 in the liver of HBxTg mice was also suppressed in the absence of iNOS, indicating the critical role for JNK in the mutual regulation of HBx- and iNOS-mediated glucose metabolism. These findings establish a novel mechanism of HBx-driven hepatic metabolic disorder that is modulated by iNOS-mediated activation of JNK.
Asunto(s)
Glucosa/biosíntesis , Virus de la Hepatitis B/metabolismo , Homeostasis , Hígado/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Transactivadores/metabolismo , Animales , Factores Relajantes Endotelio-Dependientes/metabolismo , Factores Relajantes Endotelio-Dependientes/farmacología , Regulación Enzimológica de la Expresión Génica/genética , Gluconeogénesis/genética , Glucosa/genética , Células Hep G2 , Humanos , Hiperglucemia/genética , Hiperglucemia/metabolismo , Hiperglucemia/virología , Hígado/virología , Ratones , Ratones Noqueados , Proteína Quinasa 8 Activada por Mitógenos/genética , Proteína Quinasa 8 Activada por Mitógenos/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico/farmacología , Óxido Nítrico Sintasa de Tipo II/genética , Transducción de Señal/genética , Transactivadores/genética , Proteínas Reguladoras y Accesorias ViralesRESUMEN
Hepatic steatosis is considered to have an important impact on liver tumorigenesis, despite a lack of clear experimental evidence. Histopathological analysis of H-ras12V transgenic mice showed liver lesions on a steatosis background had significantly higher incidence than on a non-steatosis background. Further investigation showed that apolipoprotein A-I was elevated and accumulated around fatty vacuoles. This elevated level of apolipoprotein A-I was coupled with an elevated level of H-ras12V protein and ROS. In conclusion, our results suggest that the expression of H-ras12V oncogene leads to elevated levels of ROS and apolipoprotein A-I that contribute to steatosis. The steatosis, in turn, promotes the development of hepatic lesions induced by H-ras12V oncogene.
Asunto(s)
Apolipoproteína A-I/metabolismo , Hígado Graso/genética , Hígado Graso/metabolismo , Genes ras , Especies Reactivas de Oxígeno/metabolismo , Animales , Hígado Graso/patología , Femenino , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Masculino , Ratones , Ratones TransgénicosRESUMEN
Hepatocellular carcinoma (HCC) is widely known to develop more frequently in cirrhotic patients with a high expression of Hepatitis B virus X protein (HBx), which is controlled by the enhancer 1 (Enh1)/X-promoter. To examine the effect of the mutations in the Enh1/X-promoter region in hepatitis B virus (HBV) genomes on the development of HCC, we investigated the differences in HBV isolated from cirrhotic patients with or without HCC along with the promoter activities of certain specific mutations within the Enh1/X-promoter. We examined 160 hepatitis B surface antigen (HBsAg)-positive cirrhotic patients (80 HCC patients, 80 non-HCC patients) by evaluating the biochemical, virological, and molecular characteristics. We evaluated the functional differences in certain specific mutations within the Enh1/X-promoter. The isolated sequences included all of the subgenotypes C2. The sites that showed higher mutation rates in the HCC group were G1053A and G1229A, which were found to be independent risk factors through multiple logistic analysis (P < 0.05). Their promoter activities were elevated 2.38- and 4.68-fold, respectively, over that of the wild type in the HepG2 cells. Similarly, both the mRNA and protein levels of HBx in these two mutants were much higher than that in wild type-transfected HepG2 cells. Mutated nucleotides of the Enh1/X-promoter, especially G1053A and G1229A mutations in the HBV subgenotype C2 of patients with cirrhosis, can be risk factors for hepatocarcinogenesis, and this might be due to an increase in the HBx levels through the transactivation of the Enh1/X-promoter.
Asunto(s)
Carcinoma Hepatocelular/etiología , Elementos de Facilitación Genéticos , Cirrosis Hepática/virología , Neoplasias Hepáticas/etiología , Mutación , Regiones Promotoras Genéticas , Transactivadores/genética , Adulto , Anciano , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Proteínas Reguladoras y Accesorias ViralesRESUMEN
Hepatitis C virus (HCV) is a major cause of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma (HCC). However, the mechanism of HCV pathogenesis is not well understood. Our previous in vitro studies suggested that non-structural 5A (NS5A) protein may play an important role in liver pathogenesis. To elucidate the mechanism of HCV-induced liver pathogenesis, we investigated the histopathological changes of liver in transgenic mice harbouring the NS5A gene. We generated transgenic mice harbouring HCV NS5A gene under the control of hepatitis B virus (HBV) enhancer. Pathological changes were analysed by immunohistochemical staining and western blot analysis. Lipid composition and reactive oxygen species (ROS) production in NS5A transgenic mice were analysed. HCV NS5A transgenic mice developed extraordinary steatosis over 6 months old and induced HCC in some mice. NS5A was co-localized with apolipoprotein A-I in fatty hepatocytes. In addition, the extraordinarily high levels of ROS, NF-kappaB and STAT3 were detected in hepatocytes of NS5A transgenic mice. These data suggest that NS5A, independent of other HCV viral proteins, may play an important role in the development of hepatic pathologies, including steatosis and hepatoceullular carcinoma in transgenic mice.
Asunto(s)
Hígado Graso/virología , Hepacivirus/patogenicidad , Neoplasias Hepáticas Experimentales/virología , Proteínas no Estructurales Virales/toxicidad , Animales , Apolipoproteína A-I/metabolismo , Progresión de la Enfermedad , Ácidos Grasos/metabolismo , Hígado Graso/metabolismo , Hígado Graso/patología , Femenino , Neoplasias Hepáticas Experimentales/metabolismo , Neoplasias Hepáticas Experimentales/patología , Masculino , Ratones , Ratones Transgénicos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo , VirulenciaRESUMEN
The hepatitis B virus X-protein (HBx), a multifunctional viral regulator, participates in the viral life cycle and in the development of hepatocellular carcinoma (HCC). We previously reported a high incidence of HCC in transgenic mice expressing HBx. In this study, proteomic analysis was performed to identify proteins that may be involved in hepatocarcinogenesis and/or that could be utilized as early detection biomarkers for HCC. Proteins from the liver tissue of HBx-transgenic mice at early stages of carcinogenesis (dysplasia and hepatocellular adenoma) were separated by 2-DE, and quantitative changes were analyzed. A total of 22 spots displaying significant quantitative changes were identified using LC-MS/MS. In particular, several proteins involved in glucose and fatty acid metabolism, such as mitochondrial 3-ketoacyl-CoA thiolase, intestinal fatty acid-binding protein 2 and cytoplasmic malate dehydrogenase, were differentially expressed, implying that significant metabolic alterations occurred during the early stages of hepatocarcinogenesis. The results of this proteomic analysis provide insights into the mechanism of HBx-mediated hepatocarcinogenesis. Additionally, this study identifies possible therapeutic targets for HCC diagnosis and novel drug development for treatment of the disease.
Asunto(s)
Carcinoma Hepatocelular/metabolismo , Regulación Neoplásica de la Expresión Génica , Hígado/patología , Transactivadores/genética , Transactivadores/metabolismo , Animales , Western Blotting , Carcinoma Hepatocelular/genética , Cromatografía Liquida , Electroforesis en Gel Bidimensional , Hígado/metabolismo , Ratones , Ratones Transgénicos , Reacción en Cadena de la Polimerasa , Proteómica , Espectrometría de Masas en Tándem , Proteínas Reguladoras y Accesorias ViralesRESUMEN
BACKGROUND/AIMS: Considering the incidence of prevailing hepatitis B virus (HBV) genotypes in neighboring nations, the predominance of genotype C in Korea is exceptional and needs to be confirmed by nationwide investigation. METHODS: A total of 510 HBsAg (+) or HBeAg (+) serum samples was collected from subjects in several cities and harbors throughout the Korean peninsula for genotype (A-G)-specific multiplex PCR analysis. Another 40 serum samples from chronic HBV carriers from Iksan city were selected for sequencing of the entire HBV genome. Phylogenetic analysis was performed with 22 whole genomic sequences of Korean HBV strains enrolled in GenBank. RESULTS: An amplicon was found in 377 specimens and genotype C occupied 98.1% (370 cases); none of the other genotypes were found. A mixed pattern of genotypes B and C was seen in seven specimens (1.9%), of which five were tested using PCR targeting the X fragment; no genotype B bands were found. With the exception of 1 case, which was subgenotype A2, whole sequences of Korean HBV strains (n=62) belonged to subgenotype C2. CONCLUSIONS: The prevailing HBV genotype in Korea is C2; the other genotypes occur only rarely. Future studies should include confirmation of the detection of genotypes other than C.
Asunto(s)
Virus de la Hepatitis B/genética , Genotipo , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B/clasificación , Humanos , Corea (Geográfico)/epidemiología , Filogenia , Precursores de Proteínas/análisis , Precursores de Proteínas/genética , Análisis de Secuencia de ADN , Proteínas del Envoltorio Viral/análisis , Proteínas del Envoltorio Viral/genéticaRESUMEN
The forkhead-box J1 (FOXJ1) transcription factor could suppress a spontaneous activation of T cells and B cells through an induction of IkappaBbeta that results in repression of NF-kappaB activity. In Foxj1 deficiency mice, systemic autoimmune inflammation is quite common symptom. Therefore, deregulated Foxj1 is supposed to be associated with autoimmune diseases and/or other inflammatory diseases. Previously, we identified that polymorphisms of human FOXJ1 gene (g.??460C>T, g.1805G>T and g.3375G>C) are associated with allergic rhinitis in a Korean population. In present study, we compared the genotype and allele frequencies of these SNPs between healthy controls and systemic lupus erythematosus (SLE) or rheumatoid arthritis (RA) patients. We also investigated the relationships between each genotype and the expression levels of anti- nuclear antibodies in SLE patients, and rheumatoid factor and anti-cyclic citrullinated peptide in RA patients. The frequencies of haplotypes constructed by these FOXJ1 SNPs were compared between controls and SLE (or RA) patients. The results of genotype and allele analysis showed that the prevalence of polymorphism g.3375G>C was associated with the susceptibility of SLE (P = 0.0072 and 0.0042, respectively). But no significant association was found with RA. In the haplotype analysis, however, the main CGG showed a weak association between controls and RA patients (P = 0.048).
Asunto(s)
Artritis Reumatoide/genética , Factores de Transcripción Forkhead/genética , Lupus Eritematoso Sistémico/genética , Polimorfismo de Nucleótido Simple , Adulto , Artritis Reumatoide/complicaciones , Pueblo Asiatico , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Haplotipos , Humanos , Corea (Geográfico) , Lupus Eritematoso Sistémico/complicaciones , Masculino , Persona de Mediana Edad , Polimorfismo GenéticoRESUMEN
Hepatitis C virus (HCV) is a pathogen that is of great medical significance in chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma worldwide. Although the HCV proteins have been intensively investigated over the past decade, the biochemical functions of the NS4B protein are still largely unknown. To investigate NS4B as a potential causative agent of liver disease, transgenic mice expressing the NS4B protein in liver tissue were produced. The transgenic animals were phenotypically similar to their normal littermates for up to 18 months of age. Our results suggest that the HCV NS4B protein is not directly cytopathic or oncogenic in our transgenic mice model.
Asunto(s)
Hepacivirus/metabolismo , Proteínas no Estructurales Virales/metabolismo , Animales , Western Blotting , Femenino , Expresión Génica/genética , Hepacivirus/genética , Inmunohistoquímica , Hígado/metabolismo , Hígado/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas no Estructurales Virales/genéticaRESUMEN
A common characteristic of hepatocellular carcinoma in humans and animals is a striking male prevalence. However, the underlying mechanisms remain largely unknown. We have reported that hepatotumorigenesis is prevalent in male H-ras12V transgenic mice (Wang et al., 2005). Orchiectomy and ovariectomy were performed to determine if the presence of sex organ-related factors contributes to hepatotumorigenesis. After orchiectomy and ovariectomy, the mice were sampled at 6 months of age. The pathological diagnosis, sex hormone levels, expression of the H-ras12V transgene, and ras related signal pathways were determined. Orchiectomy significantly reduced the incidence of hepatotumorigenesis in males. However, no significant difference was detected in the incidence of tumorigenesis between ovariectomized and non-ovariectomized females. Molecular biochemical experiments showed that the sex organ-related factors significantly influenced transgene expression, which contributed to activation of the MAPK signaling pathway. The present study demonstrates that testis-related factors play important roles in hepatotumorigenesis in H-ras12V transgenic mice.
Asunto(s)
Genes ras , Neoplasias Hepáticas Experimentales , Hígado/enzimología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Orquiectomía , Transgenes , Animales , Femenino , Hígado/metabolismo , Neoplasias Hepáticas Experimentales/enzimología , Neoplasias Hepáticas Experimentales/etiología , Neoplasias Hepáticas Experimentales/genética , Masculino , Ratones , Ratones Transgénicos , Ovariectomía , Factores Sexuales , Transducción de Señal , Testosterona/sangre , Proteínas ras/genéticaRESUMEN
The asialoglycoprotein receptor (ASGP-R) on the hepatocyte membrane is a specific targeting marker for gene and drug delivery. Polyethylenimine (PEI) is a polycationic nonviral vector that is used for gene transfer. We have synthesized galactosylated polyethylenimine-graft-poly(ethylene glycol) (GPP) for performing gene delivery to the hepatocytes. The present study reports on the in vitro and in vivo data that was achieved in hepatoma bearing transgenic mice. The cytotoxicity was decreased with the increasing PEG content. The particle size of the complex was increased with the increasing PEG at an N/P ratio of 3.0, while the zeta potentials were decreased. The (99m)Tc labeled complexes were transfected into HepG2 and HeLa cells, while the GFP reporter genes were mainly expressed in the HepG2 cells. The in vivo data was achieved in ALB/c-Ha-ras transgenic mice. (99m)Tc labeled GPP(50)/DNA was injected into the mice via the tail vein, and the gamma images were acquired at 5, 15 and 30 min. The (99m)Tc labeled complexes were mainly localized in the heart and liver, and they were excreted through the kidneys. The GFP gene was mainly expressed in the proliferating cells at the tumor periphery. This result was confirmed by PCNA staining. The GPP(50)/DNA complexes were bound to ASGP-R of the proliferating hepatocytes in vitro and in vivo. The present results demonstrate the feasibility of nonviral gene transfer using galactosylated PEI-PEG in vivo.
Asunto(s)
Receptor de Asialoglicoproteína/efectos de los fármacos , Receptor de Asialoglicoproteína/genética , Sistemas de Liberación de Medicamentos , Terapia Genética/métodos , Polietilenglicoles/química , Transfección/métodos , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , ADN/biosíntesis , ADN/genética , Electroquímica , Regulación de la Expresión Génica/genética , Regulación de la Expresión Génica/fisiología , Genes ras/genética , Proteínas Fluorescentes Verdes/genética , Hepatocitos/efectos de los fármacos , Neoplasias Hepáticas Experimentales/diagnóstico por imagen , Neoplasias Hepáticas Experimentales/terapia , Ratones , Ratones Transgénicos , Cintigrafía , Tecnecio , Sales de Tetrazolio , TiazolesRESUMEN
Using miRNA microarray analysis, we identified 31 miRNAs that were significantly up-regulated or down-regulated in colon cancer tissues. We chose MIR196B, which was specifically up-regulated in colon cancer, for further study. We identified 18 putative MIR196B target genes by comparing between the mRNAs down-regulated in MIR196B-overexpressed cells and the assumed MIR196B target genes predicted by public bioinformatics tools. The association between MIR196B and FAS was verified in this study. FAS expression was constitutively elevated in normal human colorectal tissues. However, its expression was often reduced in human colorectal cancer. The decrease in FAS expression could be responsible for the reduction of apoptosis in colorectal cancer cells. In colorectal cancer tissue, we showed that MIR196B up-regulation was mutually followed by down regulation of FAS expression. We also showed that MIR196B directly repressed FAS expression in colorectal cells. Furthermore, anti-MIR196B up-regulated FAS expression and increased apoptosis in colorectal cancer cell lines. Our results suggest that the up-regulation of MIR196B modulates apoptosis in colorectal cancer cells by partially repressing FAS expression and that anti-MIR196B could be a potential candidate as an anti-cancer drug in colorectal cancer therapy.
Asunto(s)
Apoptosis , Neoplasias Colorrectales/metabolismo , MicroARNs/metabolismo , Receptor fas/metabolismo , Anciano , Antimetabolitos Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Células CACO-2 , Estudios de Casos y Controles , Caspasa 3/genética , Caspasa 3/metabolismo , Caspasa 7/genética , Caspasa 7/metabolismo , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Biología Computacional , Femenino , Fluorouracilo/farmacología , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica , Células HT29 , Humanos , Masculino , MicroARNs/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Transducción de Señal , Transfección , Receptor fas/genéticaRESUMEN
The signaling mechanisms that control apoptotic events evoked by iron chelators are largely unknown. We found that cAMP response element-binding protein (CREB) is cleaved during iron chelator deferoxamine (DFO)-induced apoptosis, and that the cleavage is largely prevented by the cell-permeable analog of cAMP, dibutyryl-cAMP (dbcAMP), a known CREB activator. In addition, dbcAMP profoundly reduced DFO-induced apoptosis along with significant suppression of caspase-3 and -8 activation and inhibition of loss of mitochondrial potential. These results led us to investigate whether CREB activation is functionally connected with the MAPK family members because we previously demonstrated that p38 kinase is involved in iron chelator-induced apoptosis of HL-60 cells. dbcAMP by itself rapidly induced CREB phosphorylation but dramatically inhibited DFO-induced phosphorylation of all three MAPK family members. However, disruption of CREB expression by antisense oligodeoxyribonucleotide (AS-ODN) only restored p38 kinase activation, and simultaneously attenuated dbcAMP-induced protection of HL-60 cells from DFO-induced cell death. Conversely, inhibition of p38 kinase activity by SB203580 significantly reduced DFO-induced CREB cleavage as well as apoptosis, indicating a cross-talk between CREB and p38 kinase. Collectively, these results demonstrate that cAMP-dependent CREB activation plays an important role in protecting HL-60 cells from iron chelator-induced apoptosis, presumably through downregulation of p38 kinase.
Asunto(s)
Apoptosis/efectos de los fármacos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Deferoxamina/farmacología , Quelantes del Hierro/farmacología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Transducción de Señal/efectos de los fármacos , Caspasas/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/antagonistas & inhibidores , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Regulación hacia Abajo , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Células HL-60 , Humanos , Oligodesoxirribonucleótidos Antisentido/farmacología , Fosforilación/efectos de los fármacos , Proteínas Quinasas p38 Activadas por MitógenosRESUMEN
The aim of the present study was to investigate the intracellular mediators of the third base mutant of codon 249 in p53 gene (p53mt249) mutation that potentiate IGF-II dependent IGF-I receptor (IGF-IR) signaling. p53mt249 enhanced IGF-II dependent IGF-IR signaling in p53 negative Hep3B hepatoma cells which were specifically prevented by IGF-IR antibody, alpha IR3 and lovastin. p53mt249 increased the number of IGF-II binding sites with no change in the affinity of IGF-IR. Enhanced levels of IGF-IR expression and transcription were identified in p53mt249 transfected Hep3B cells. Pre-transfection of cultured hepatoma cells with p53mt249 resulted in a three to fourfold increase in IGF-IR phosphorylation and downstream mediator IRS-I phosphorylation but, enhanced more than 15-fold after IGF-II treatment, which coincides well with the cell growth and thymidine uptake results. Our results showed that p53mt249 modulate IGF-II dependent IGF-IR signaling by upregulating IGF-IR and potentiating IGF-IRs where IGF-IRs became more sensitive on treatment with IGF-II. We concluded that p53mt249 stimulates IGF-II dependent IGF-IR signaling by upregulating the expression of both ligand (IGF-II) and receptor (IGF-IR) through an autocrine and/or paracrine loop and we outline the physiological significance of potentiation of IGF-IR by p53 mutation in the development of hepatocellular carcinoma (HCC).
Asunto(s)
Factor II del Crecimiento Similar a la Insulina/metabolismo , Mutación , Transducción de Señal/genética , Proteína p53 Supresora de Tumor/fisiología , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/patología , Comunicación Celular , División Celular , Línea Celular Tumoral , Humanos , Factor II del Crecimiento Similar a la Insulina/genética , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/fisiología , Activación Transcripcional , Proteína p53 Supresora de Tumor/genéticaRESUMEN
The enzyme complex 3beta-hydroxysteroid dehydrogenase/Delta5-Delta4-isomerase (3beta-HSD) is involved in the biosynthesis of all classes of active steroids. The expression of 3b-HSD in human uterine endometrium during the menstrual cycle and decidua was examined in an effort to understand its role during ova implantation. 3beta-HSD was weakly expressed in the glandular epithelium of the proliferative phase and moderately expressed in the glandular epithelium of secretory phase of the endometrium. In the decidua of the ectopic pregnancy, 3beta-HSD was strongly expressed. The human uterine endometrial 3beta-HSD was identified as being the same type as the placental 3beta-HSD by RT-PCR and sequence analysis. In addition to the expression of 3beta-HSD, P450scc was expressed in the decidua of the ectopic pregnancy. These results suggest that pregnenolone might be synthesized from cholesterol by P450scc de novo and then, it is converted to progesterone by 3beta-HSD in the uterine endometrium. The data implies that the endometrial 3beta-HSD can use not only the out-coming pregnenolone from the adrenal gland but also the self- made pregnenolone to produce progesterone. The de novo synthesis of progesterone in the endometrium might be a crucial factor for implantation and maintenance of pregnancy.
Asunto(s)
Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/biosíntesis , Endometrio/enzimología , Complejos Multienzimáticos/biosíntesis , Progesterona Reductasa/biosíntesis , Esteroide Isomerasas/biosíntesis , Colesterol/química , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/genética , Decidua/enzimología , Femenino , Expresión Génica/fisiología , Humanos , Ciclo Menstrual/fisiología , Complejos Multienzimáticos/genética , Placenta/enzimología , Embarazo , Pregnenolona/biosíntesis , Progesterona/biosíntesis , Progesterona Reductasa/genética , Esteroide Isomerasas/genéticaRESUMEN
Hepatitis C virus (HCV) is a major causative agent in liver disease. In order to investigate if Korean type HCV core protein and its related mutants, S99Q and S1161, are cytopathic to liver, three types of transgenic mice were established. The expression of transgenes was confirmed by HCV specific RT-PCR and Western immunoblotting. The livers of all wild type core and S1161 transgenic lineages remained largely histologically normal. However, the livers of the S99Q transgenic mice showed significant high level of cell dysplasia associated with the transgene expression in hepatocytes largely located around the central veins by in situ hybridization analysis. In conclusion, the mutant HCV core protein at S99Q may contribute to the progress of HCV induced liver disease.
Asunto(s)
Hepatitis C/patología , Hepatitis Viral Animal/patología , Hígado/virología , Proteínas del Núcleo Viral/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Expresión Génica , Vectores Genéticos/genética , Hepatitis C/virología , Hepatitis Viral Animal/virología , Hepatocitos/patología , Hepatocitos/virología , Hígado/patología , Ratones , Ratones Transgénicos , Datos de Secuencia Molecular , Mutación/genética , ARN Mensajero/química , ARN Mensajero/metabolismo , Transgenes , Proteínas del Núcleo Viral/análisis , Proteínas del Núcleo Viral/metabolismoRESUMEN
The epithelial cells of the mammary gland go through a cycle of growth, differentiation, and involution during pregnancy. Recently, we found that interleukin-10 (IL-10) was induced at the involution stage and contributed to apoptosis in the mammary gland. To elucidate the role of the epithelial cells in involution, we examined IL-10 expression in an in vitro model of HC11 cells, in various culture conditions. IL-10 was weakly expressed early in growth but when the cells were induced to differentiate by insulin and dexamethasone expression increased slightly. Prolactin in combination with insulin and dexamethasone caused a further increase. To mimic apoptosis the culture was deprived of serum as well as hormones, and this resulted in a gradual increase in IL-10. In contrast with its ligand, the IL-10 receptor itself was not expressed in any conditions. We speculate that release of IL-10 from the epithelial cells recruits lymphocytes, which have IL-10 receptors on their cell membranes, and they in turn secrete death factors inducing apoptosis of the epithelial cells.
Asunto(s)
Diferenciación Celular/fisiología , Células Epiteliales/metabolismo , Interleucina-10/metabolismo , Linfocitos/metabolismo , Glándulas Mamarias Animales/metabolismo , Prolactina/farmacología , Regulación hacia Arriba , Animales , Apoptosis/fisiología , División Celular/fisiología , Células Cultivadas , Medio de Cultivo Libre de Suero , Dexametasona/farmacología , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Femenino , Insulina/farmacología , Glándulas Mamarias Animales/efectos de los fármacos , Ratones , Embarazo , Receptores de Interleucina/metabolismo , Receptores de Interleucina-10RESUMEN
AIM: To investigate the effect of methylsulfonylmethane (MSM), recently reported to have anti-cancer effects, in liver cancer cells and transgenic mice. METHODS: Three liver cancer cell lines, HepG2, Huh7-Mock and Huh7-H-ras (G12V), were used. Cell growth was measured by Cell Counting Kit-8 and soft agar assay. Western blot analysis was used to detect caspases, poly (ADP-ribose) polymerase (PARP), and B-cell lymphoma 2 (Bcl-2) expressions. For in vivo study, we administered MSM to H-ras (12V) transgenic mice for 3 mo. RESULTS: MSM decreased the growth of HepG2, Huh7-Mock and Huh7-H-ras (G12V) cells in a dose-dependent manner. That was correlated with significantly increased apoptosis and reduced cell numbers in MSM treated cells. Cleaved caspase-8, cleaved caspase-3 and cleaved PARP were remarkably increased in the liver cancer cells treated with 500 mmol/L of MSM; however, Bcl-2 was slightly decreased in 500 mmol/L. Liver tumor development was greatly inhibited in the H-ras (12V) transgenic mice treated with MSM, compared to control, by showing reduced tumor size and number. Cleaved PARP was significantly increased in non-tumor treated with MSM compared to control. CONCLUSION: Liver injury was also significantly attenuated in the mice treated with MSM. Taken together, all the results suggest that MSM has anti-cancer effects through inducing apoptosis in liver cancer.
RESUMEN
BACKGROUND: Interleukin 31 (IL-31) is a T helper type 2 effector cytokine that plays an important role in the pathogenesis of atopic and allergic diseases. IL-31 may be involved in promoting allergic inflammation and in inducing airway epithelial responses such as allergic asthma. METHODS: Single-base extension analysis was used to detect the genotypes of IL-31 single nucleotide polymorphisms (SNPs), and we compared the genotype and allele frequencies of the IL-31 SNPs between patients with asthma and healthy controls. RESULTS: There were no significant differences in the genotype and allele frequencies of the IL-31 SNPs between patients with asthma and healthy controls. Furthermore we compared the genotype and allele frequencies of IL-31 SNPs between patients with atopic asthma, those with non-atopic asthma and healthy controls. This showed that the SNPs were not associated with the susceptibility to atopic asthma. There were no significant differences in the haplotype frequencies of IL-31 SNPs between patients with asthma and healthy controls. In patients with asthma, the IL-31 SNPs were significantly correlated with total serum levels of IgE (p=0.035). CONCLUSIONS: Our results indicate that, the IL-31 SNPs may be associated with IgE production in patients with asthma.
RESUMEN
RATIONALE AND OBJECTIVES: The aims of this study were to evaluate the morphologic characteristics and growth pattern of hepatic tumors in H-ras 12V transgenic (TG) mice using a micro-magnetic resonance (MR) system and to assess the usefulness of gadolinium ethoxybenzyl diethylenetriamine penta-acetic acid (Gd-EOB-DTPA) enhancement for the detection of hepatic tumors in these mice. MATERIALS AND METHODS: Hepatocellular carcinoma lines were established to allow insertion of the H-ras 12V transgene under the control of the albumin enhancer/promoter. Seven H-ras 12V TG mice and four wild-type mice were included in this study. The mice underwent various MR imaging examinations, including T1-weighted imaging (repetition time, 300 ms; echo time, 11 ms), Gd-EOB-DTPA-enhanced T1-weighted imaging (dose, 0.025 mmol/kg), and T2-weighted imaging (repetition time, 3500 ms; echo time, 36 ms), with a 4.7-T MR scanner, at 4, 6, 8, and 9 months of age. All mice were euthanized after the final MR imaging procedure, except for one TG mouse and two wild-type mice that were euthanized after MR imaging procedures at 4 months of age. For imaging analysis, the tumor characteristics in each MR sequence, including tumor size, number, and signal intensity (SI), were recorded, and the contrast-to-noise ratio and contrast enhancement ratio were calculated to quantify the SI of the tumor. The MR images were correlated with the findings of histopathologic examinations. RESULTS: No tumors were detected in the four wild-type mice. In the six TG mice, a total of 67 tumors were found in histopathologic specimens obtained at 9 months of age. Of the 67 tumors, 62 were detected on Gd-EOB-DTPA-enhanced T1-weighted images with fat saturation. The majority of hepatic tumors showed high SI on T1-weighted images without fat saturation. The SI diminished on T1-weighted images with fat saturation. The tumor contrast-to-noise ratio for Gd-EOB-DTPA-enhanced T1-weighted imaging was significantly better than that for the other sequences. The tumors were histopathologically confirmed as hepatocellular adenomas (n = 32) and well-differentiated hepatocellular carcinomas (n = 35). CONCLUSIONS: Micro-MR imaging can reveal the characteristics of hepatic tumors in a live murine model. Gd-EOB-DTPA-enhanced T1-weighted imaging is helpful in the detection of hepatic tumors in H-ras 12V TG mice.
Asunto(s)
Carcinoma Hepatocelular/patología , Medios de Contraste , Gadolinio DTPA , Aumento de la Imagen/métodos , Neoplasias Hepáticas Experimentales/patología , Imagen por Resonancia Magnética/métodos , Animales , Diagnóstico Diferencial , Modelos Animales de Enfermedad , Genes ras , Hígado/patología , Ratones , Ratones Transgénicos , Variaciones Dependientes del ObservadorRESUMEN
Unlike other forms of hepatocellular carcinoma (HCC), HCC induced by hepatitis B virus (HBV) infection shows a poor prognosis after conventional therapies. HBV induces liver cirrhosis and HCC. Many researchers have made efforts to find new substances that suppress the activity of HBV. Curcuma longa Linn (CLL) has been used for traditional medicine and food in Asia, especially in India, and has shown chemopreventive effects in a HBV-related in vitro model. This in vivo study was designed to seek the chemopreventive effects of CLL and its mechanisms. CLL mixture concentrated with dextrose water by boiling was lyophilized. CLL extracts were administrated to HBV X protein (HBx) transgenic mice aged 4 weeks for 2 to 4 weeks and aged 6 months for 3 months. After administration, histological changes in the liver tissue and expression of HBx-related genes were investigated. CLL-treated mice showed less visceral fat, a smaller liver/body weight ratio and delayed liver pathogenesis. Proliferating cell nuclear antigen (PCNA) expression was also increased in CLL-treated HBx transgenic mice, indicating regeneration of damaged liver tissue. CLL treatment decreased expression of HBx and increased p21 and cyclin D1 in livers of HBx transgenic mice. In addition, p-p53 was increased after CLL treatment. These results suggest that CLL can have beneficial effects on the early and late stages of liver pathogenesis, preventing and delaying liver carcinogenesis. This drug should be considered as a potential chemopreventive agent for HBV-related hepatocarcinogenesis.