RESUMO
The NF-kB (nuclear factor kB) pathway is involved in the proliferation of many cell types. To explore the mechanism of the NF-kB signaling pathway underlying the oval cell proliferation during rat liver regeneration, the Rat Genome 230 2.0 Array was used to detect expression changes of NF-kB signaling pathway-related genes in oval cells. The results revealed that the expression levels of many genes in the NF-kB pathway were significantly changed. This included 48 known genes and 16 homologous genes, as well as 370 genes and 85 homologous genes related to cell proliferation. To further understand the biological significance of these changes, an expression profile function was used to analyze the potential biological processes. The results showed that the NF-kB pathway promoted oval cell proliferation mainly through three signaling branches; the tumor necrosis factor alpha branch (TNF-a pathway), the growth factor branch, and the chemokine branch. An integrated statistics method was used to define the key genes in the NF-kB pathway. Seven genes were identified to play vital roles in the NF-kB pathway. To confirm these results, the protein content, including two key genes (TNF and FGF11) and two non-key genes (CCL2 and TNFRSF12A), were analyzed using two-dimensional gel electrophoresis and MALDI-TOF/TOF mass spectrometry. The results were generally consistent with those of the array data. To conclude, three branches and seven key genes were involved in the NF-kB signaling pathway that regulates oval cell proliferation during rat liver regeneration.
Assuntos
Proliferação de Células , Regeneração Hepática , Fígado/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Animais , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Fígado/citologia , Fígado/fisiologia , NF-kappa B/genética , Ratos , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/metabolismo , Receptor de TWEAK , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Previous studies have demonstrated that the nuclear factor κB (NF-κB) pathway is involved in promoting cell proliferation. To further explore the regulatory branches and their sequence in the NF-κB pathway in the promotion of hepatocyte proliferation at the transcriptional level during rat liver regeneration, Rat Genome 230 2.0 array was used to detect the expression changes of the isolated hepatocytes. We found that many genes involved in the NF-κB pathway (including 73 known genes and 19 homologous genes) and cell proliferation (including 484 genes and 104 homologous genes) were associated with liver regeneration. Expression profile function (Ep) was used to analyze the biological processes. It was revealed that the NF-κB pathway promoted hepatocyte proliferation through three branches. Several methods of integrated statistics were applied to extract and screen key genes in liver regeneration, and it indicated that eight genes may play a vital role in rat liver regeneration. To confirm the above predicted results, Ccnd1, Jun and Myc were analyzed using qRT-PCR, and the results were generally consistent with that of microarray data. It is concluded that 3 branches and 8 key genes involved in the NF-κB pathway regulate hepatocyte proliferation during rat liver regeneration.
Assuntos
Hepatócitos/citologia , Hepatócitos/metabolismo , Regeneração Hepática/genética , NF-kappa B/metabolismo , Transdução de Sinais/genética , Animais , Proliferação de Células , Regulação da Expressão Gênica , Modelos Biológicos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Reação em Cadeia da Polimerase em Tempo RealRESUMO
We examined the gene expression profiles of the 5-hydroxytryptamine signaling pathway in the regenerating liver and 8 types of liver cells during rat liver regeneration, and explored expression differences in 5-hydroxytryptamine signaling pathway genes at the level of tissues and cells, as well as the role of the pathway on liver regeneration. Eight types of rat regenerating liver cells were isolated using Percoll density-gradient centrifugation and immunomagnetic bead methods. Rat Genome 230 2.0 Array was used to detect expression changes in 5-hydroxytryptamine signaling pathway genes. The results showed that 26, 47, 8, 21, 16, 19, 22, 27, and 20 genes changed significantly in hepatocytes, biliary epithelial cells, hepatic stellate cells, oval cells, sinusoidal endothelial cells, Kupffer cells, pit cells, dendritic cells, and the regenerating liver, respectively. Synthetic effects of 5-hydroxytryptamine signaling pathway genes in 8 types of liver cells showed that 26 genes were expressed significantly; the expression trends of 10 genes were the same in the regenerating liver, while others were different. Based on the gene expression profiles of the 8 types of liver cells, 5-hydroxytryptamine promoted hepatocyte proliferation through the RAS and STAT3 signaling pathways, proliferation and differentiation of sinusoidal endothelial cells through the STAT3 signaling pathway, and proliferation and apoptosis of pit cells through the AKT3 signaling pathway. There were large differences in genes involved in 5-hydroxytryptamine signaling at the tissue and cellular levels; thus, liver regeneration should be studied in-depth at the cellular level to reveal the molecular mechanism of liver regeneration.
Assuntos
Hepatócitos/metabolismo , Regeneração Hepática , Serotonina/fisiologia , Transcriptoma , Animais , Células Cultivadas , Feminino , Perfilação da Expressão Gênica , Fígado/citologia , Fígado/metabolismo , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Ratos Sprague-Dawley , Transdução de SinaisRESUMO
Liver cancer (LC) is generally characterized by malignant cell proliferation and growth; it normally develops in stages that progress from non-specific injury of the liver to liver fibrosis, liver cirrhosis, dysplasia nodules, and liver carcinoma. We used a rat model of diethylnitrosamine (DENA)-induced LC; a Rat Genome 230 2.0 Array was used to detect gene expression profile of liver tissues from male rats 5, 8, 12, 16, and 18 weeks following the beginning of DENA-induced LC. We found 909 known genes, including 637 up-regulated, 270 down-regulated, and two up/down-regulated genes, that were significantly changed in expression. Among them, 108 genes were expressed at the 5th, 213 at the 8th, 516 at the 12th, 698 at the 16th, and 506 at the 18th week of DENA-induced LC. Methods in bioinformatics and systems biology were applied to explore the correlation between the gene expression profile of rat liver tissue and liver cancer occurrence at the transcriptional level; 23 physiological activities were found to be associated with LC. Among these, eight physiological activities, including stimulus response, inflammation and immune response, oxidative reduction, cell proliferation, differentiation, migration, adhesion, and angiogenesis were increased, implying that they could play important roles in the occurrence and development of LC. In addition, carbohydrate, lipid, and organic acid metabolism were decreased, suggesting that liver injury induced by a carcinogenic agent has a negative effect on the metabolism of fundamental substances.
Assuntos
Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Fígado/metabolismo , Fígado/patologia , Animais , Dietilnitrosamina , Modelos Animais de Doenças , Progressão da Doença , Fígado/fisiopatologia , Neoplasias Hepáticas/fisiopatologia , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos TestesRESUMO
Hepatic pit cells are a population of large granular lymphocytes that substantially contribute to hepatic immunity. Studies have proven that pit cells have a role in liver regeneration, but the details of the relationship between pit cells and liver regeneration is not clear at present. We subjected rats to a two-third hepatectomy; pit cells with high purity were obtained with Percoll density centrifugation and immunomagnetic bead methods, and the changes in mRNA levels in pit cells from the regenerating liver were monitored up to 168 h using a Rat Genome 230 2.0 Array composed of 25,020 distinct rat liver cDNA clones. Of the 25,020 genes analyzed, 612 known and 358 unknown genes were identified to be associated with liver regeneration. The 612 known genes are classified into up-regulation and down-regulation patterns based on the expression levels; they primarily participate in at least 23 biological activities based on gene ontology analysis. Together with gene function enrichment analysis, cytokines and a growth factor-mediated pathway in pit cells were activated at an early phase of liver regeneration; pit cell proliferation occurred from 24-72 h after liver hepatectomy; the machinery of pit cell differentiation commenced early and came into play late; an immune/inflammatory response was enhanced late. Expression pattern analysis of functionally classified genes in pit cells can give insights into the relationship between pit cells and liver regeneration.