Full text
| |
| Author(s): |
Graziela Batista da Silva
Total Authors: 1
|
| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Conjunto das Químicas (IQ e FCF) (CQ/DBDCQ) |
| Defense date: | 2011-09-26 |
| Examining board members: |
Primavera Borelli Garcia;
Laurecir Gomes;
Marinilce Fagundes dos Santos
|
| Advisor: | Primavera Borelli |
| Abstract | |
Malnutrition affects 925 million people worldwide, regardless of age and social class, the most affected individuals are hospitalized, children and elderly.Malnutrition causes physiological changes in various tissues.The hematopoietic tissue is affected in protein malnutrition, because it is a tissue of high and constant need of proteins, leading to hematological abnormalities such as anemia and leucopenia. Studies from our laboratory have demonstrated in vivo changes in the hematopoietic microenvironment in mice submitted to protein malnutrition, and bone marrow hypoplasia, quantitative changes of the extracellular matrix (ECM) as the increase in deposit fibronectin in the region subendosteal (site of attachment of the cells stem / progenitor), changes in cell cycle of stem cells / progenitor and changes in the expression of VLA5; main integrin interaction of cells to fibronectin. Therefore this project proposes to evaluate possible isoforms of fibronectin molecule, to better understand its biological role in cell cycle stem cells / progenitor in a model of protein malnutrition. Mice were used for this C57BLI/6J male adults were kept in metabolic gaioleiros, separated into two groups. The control group received a ration normoproteíca with 12% protein and the malnourished group, a low protein diet with 2% protein over a period of 5 weeks. After this period the animals were sacrificed for hematological evaluation, bone marrow cellularity, and quantification of fibronectin isoforms research, analysis of protein profiles in marrow stroma in long-term cultures and analysis of the establishment of bone marrow stroma in long-term cultures. The malnourished animals showed a lower cellularity and a significant decrease of young cells in the bone marrow.The bone marrow stromal cultures established in long-term animal malnourished group had a lower convergence in the control group. It was also observed in cultures long term a significant increase in fibronectin on the 28th day of culture, but with a decrease in fibronectin 35 th day, but with a smaller amount of EDA region in both periods analyzed (binding site of integrins to fibronectin) compared to the control group.The survey of isoforms of fibronectin in bone marrow stroma, by RT-PCR revealed that both control animals and animals in the malnourished group presented different isoforms of fibronectin, but it was not possible to make a quantitative analysis of the regions of alternative splicing.The protein profile of long-term cultures analyzed using two-dimensional electrophoresis showed that animals of the malnourished group have a protein profile different from the control group was also observed a difference in protein profile between 28° and 35° day of culture. Therefore, the quantitative change of the molecule fibronectin and the region of EDA, as well as the presence of different isoforms of fibronectin, together with changes in protein profile may be due to an increase, or degradation of extracellular matrix proteins. And these changes may be responsible for bone marrow hypoplasia and alteration of the cell cycle of stem cells / progenitor and stromal cells; perhaps because of less interaction with integrins, this interaction is essential for the modulation of various cellular functions such as proliferation and differentiation and to regulation of extracellular matrix remodeling. But it is still necessary to quantify the areas of alternative splicing, sequencing of the extracellular matrix proteins and identification of possible metalaproteinases present in bone marrow stroma to better elucidate the roles of fibronectin and other extracellular matrix proteins in maintaining hemopoese. (AU) | |
| FAPESP's process: | 09/03162-6 - Evaluation of fibronectin isoforms in bone marrow of mice subjected to protein malnutrition |
| Grantee: | Graziela Batista da Silva |
| Support Opportunities: | Scholarships in Brazil - Master |