Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros

Bases de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Cancer Cell Int ; 17: 5, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28053600

RESUMO

BACKGROUND: Hepatocellular carcinoma is a common cancer, ranking third in cancer-associated deaths. An important cause of cancer patients' mortality is metastasis. At the start of metastasis progression, there is an epithelial-mesenchymal transition, characterized by matrix degradation, junction reductions and vessels formation. HuH-7 is a cell line used in research as an in vitro model for hepatocellular carcinoma. It is known that two-dimensional growth reflects tumor characteristics poorly. In contrast, three-dimensional cultures provide a better approach to the study of tumorigenic potential. The purpose of this work was to mimic a three-dimensional environment in order to assess gene expression of some epithelial-mesenchymal transition and metastasis progression markers in HuH-7 cells and compare them with traditional two-dimensional culture model. METHODS: HuH-7 cells were encapsulated in sodium alginate (three-dimensional model) to be compared with cells grown in two-dimensional flasks. After 4 days in culture, gene expression of Matrix metallopeptidase 9, Occludin, p65, Intercellular adhesion molecule 1 and Vascular endothelial growth factor A was analyzed by qPCR and cytoskeleton assessment was performed by rhodamine-phalloidin staining. RESULTS: Differences were found in gene expression, with a high increment of Matrix metallopeptidase 9 and Occludin reduction. The cytoskeleton morphology also showed differences, with a cytoplasm restricted only near the nuclei in the three-dimensional model. CONCLUSIONS: This work shows the effects of using sodium alginate capsules as a three-dimensional model to the study of HuH-7. Cells in this 3D system show key markers of epithelial-mesenchymal transition, such as Matrix metallopeptidase 9 overexpression and Occludin down-regulation.

2.
Liver Transpl ; 22(11): 1562-1572, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27509591

RESUMO

Acute liver failure (ALF) is characterized by massive hepatocyte cell death. Kupffer cells (KC) are the first cells to be activated after liver injury. They secrete cytokines and produce reactive oxygen species, leading to apoptosis of hepatocytes. In a previous study, we showed that encapsulated platelets (PLTs) increase survival in a model of ALF. Here, we investigate how PLTs exert their beneficial effect. Wistar rats submitted to 90% hepatectomy were treated with PLTs encapsulated in sodium alginate or empty capsules. Animals were euthanized at 6, 12, 24, 48, and 72 hours after hepatectomy, and livers were collected to assess oxidative stress, caspase activity, and gene expression related to oxidative stress or liver function. The number of KCs in the remnant liver was evaluated. Interaction of encapsulated PLTs and KCs was investigated using a coculture system. PLTs increase superoxide dismutase and catalase activity and reduce lipid peroxidation. In addition, caspase 3 activity was reduced in animals receiving encapsulated PLTs at 48 and 72 hours. Gene expression of endothelial nitric oxide synthase and nuclear factor kappa B were elevated in the PLT group at each time point analyzed. Gene expression of albumin and factor V also increased in the PLT group. The number of KCs in the PLT group returned to normal levels at 12 hours but remained elevated in the control group until 72 hours. Finally, PLTs modulate interleukin (IL) 6 and IL10 expression in KCs after 24 hours of coculture. In conclusion, these results indicate that PLTs interact with KCs in this model and exert their beneficial effect through reduction of oxidative stress that results in healthier hepatocytes and decreased apoptosis. Liver Transplantation 22 1562-1572 2016 AASLD.


Assuntos
Apoptose/efeitos dos fármacos , Terapia Biológica/métodos , Plaquetas , Células de Kupffer/efeitos dos fármacos , Falência Hepática Aguda/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Animais , Caspase 3/metabolismo , Técnicas de Cocultura , Modelos Animais de Doenças , Hepatectomia , Humanos , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Células de Kupffer/metabolismo , Fígado/citologia , Masculino , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/efeitos adversos
3.
Genet Mol Biol ; 37(1 Suppl): 149-50, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24764750

RESUMO

The Latin American School of Human and Medical Genetics (ELAG) is the main course of its kind in the genetics field in Latin America. Here we describe the main challenges regarding the organization of such event, including how we obtain funding and how we proceed with student selection. Thus, we aim to share our experience with other groups that intend to follow this format to create similar events in other areas in this region of the world.

5.
Stem Cells Int ; 2017: 5270527, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28326105

RESUMO

Acute liver failure is a complex and fatal disease. Cell-based therapies are a promising alternative therapeutic approach for liver failure due to relatively simple technique and lower cost. The use of semipermeable microcapsules has become an interesting tool for evaluating paracrine effects in vivo. In this study, we aimed to assess the paracrine effects of bone marrow mononuclear cells (BMMC) encapsulated in sodium alginate to treat acute liver failure in an animal model of 90% partial hepatectomy (90% PH). Encapsulated BMMC were able to increase 10-day survival without enhancing liver regeneration markers. Gene expression of Il-6 and Il-10 in the remnant liver was markedly reduced at 6 h after 90% PH in animals receiving encapsulated BMMC compared to controls. This difference, however, was neither reflected by changes in the number of CD68+ cells nor by serum levels of IL6. On the other hand, treated animals presented increased caspase activity and gene expression in the liver. Taken together, these results suggest that BMMC regulate immune response and promote apoptosis in the liver after 90% PH by paracrine factors. These changes ultimately may be related to the higher survival observed in treated animals, suggesting that BMMC may be a promising alternative to treat acute liver failure.

6.
Stem Cells Int ; 2016: 4831524, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26649048

RESUMO

Background and Aims. The use of bone marrow cells has been suggested as an alternative treatment for acute liver failure. In this study, we investigate the effect of encapsulated whole bone marrow cells in a liver failure model. Methods. Encapsulated cells or empty capsules were implanted in rats submitted to 90% partial hepatectomy. The survival rate was assessed. Another group was euthanized at 6, 12, 24, 48, and 72 hours after hepatectomy to study expression of cytokines and growth factors. Results. Whole bone marrow group showed a higher than 10 days survival rate compared to empty capsules group. Gene expression related to early phase of liver regeneration at 6 hours after hepatectomy was decreased in encapsulated cells group, whereas genes related to regeneration were increased at 12, 24, and 48 hours. Whole bone marrow group showed lower regeneration rate at 72 hours and higher expression and activity of caspase 3. In contrast, lysosomal-ß-glucuronidase activity was elevated in empty capsules group. Conclusions. The results show that encapsulated whole bone marrow cells reduce the expression of genes involved in liver regeneration and increase those responsible for ending hepatocyte division. In addition, these cells favor apoptotic cell death and decrease necrosis, thus increasing survival.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA