Banca de QUALIFICAÇÃO: ANGÉLICA FERNANDES GURGEL DE SOUSA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : ANGÉLICA FERNANDES GURGEL DE SOUSA
DATA : 03/03/2017
HORA: 14:00
LOCAL: Sala Carl Peter von Dietrich
TÍTULO:

Sulphated Polysaccharides from Seaweed for Bone Regeneration: Evaluation of Osteogenic Potential and Genotoxicity

PALAVRAS-CHAVES:

Sulphated polysaccharides, Regenerative medicine, Osteogenic differentiation, Genotoxicity.

PÁGINAS: 67
GRANDE ÁREA: Ciências Biológicas
ÁREA: Bioquímica
RESUMO:

The use of mesenchymal stem cells (MSCs), biomaterials and bioactive molecules, are extensively described in the strategies used in bone regenerative medicine. Among the possible sources for obtaining MSCs, Wharton’s jelly isolated cells (WJ-MSCs) of umbilical cords are preferred because they present intermediate characteristics between embryonic (ESC) and adult stem cells, avoiding variations related to the donor’s age and the fact that they can be easily isolated without raising ethical issues. Regarding the used biomolecules, fucoidan, which are sulphated polysaccharides (SPs) isolated from marine macroalgae showed osteogenic activity, suggesting their potential application in bone regeneration. Fucoidan is commercially available, being a mixture of SPs extracted from the brown algae Fucus vesiculosus, limiting its pharmacological applications. SPs extracted from other types of algae also have biological activities, however, the SPs extracted from green algae are still so little explored for applications in regenerative medicine. Another important aspect for the biomedical application of these SPs is their genotoxicity evaluation. Thus, in this work we evaluated the osteogenic activity of the commercial fucoidan of F. vesiculosus as well as of samples obtained from its subfractionation and the extract rich in SPs extracted from the green alga Caulerpa Sertularioides (CS) in WJ-hMSC. In addition, the genotoxic potential of the samples rich in SPs that presented osteogenic potential through the cytokinesis-block micronucleus (CBMN) assay was studied. MTT results indicate that samples rich in SPs, up to 10 μg.mL-1, did not show significant cytotoxicity over 72 h. Alkaline phosphatase (ALP) activity and mineralization assays suggest that the subfractions obtained from fucoidan have different activities. Thus, the FUC 0.5 subfraction (5 μg.mL-1) increased  the ALP activity by 159% over the negative control. In relation to the results obtained with the CS total extract, the highest increase (157%) was observed for 5 μg.mL-1, being higher than that observed for the positive control (65%). Fucoidan total extract, Fuc 0.5 subfraction and CS total extract induced increased calcium accumulation when added to the osteogenic medium, suggesting that they act synergistically. The CBMN results suggested that these SPs-rich samples do not show genotoxicity under the tested conditions, indicating that they may be an alternative to bone regeneration therapies.

MEMBROS DA BANCA:
Interno - 2195251 - HUGO ALEXANDRE DE OLIVEIRA ROCHA
Externo à Instituição - MARCOS FELIPE DE OLIVEIRA GALVÃO - UFRN
Presidente - 1199127 - SILVIA REGINA BATISTUZZO DE MEDEIROS