Banca de QUALIFICAÇÃO: MARINA ROCHA DO NASCIMENTO DANTAS

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : MARINA ROCHA DO NASCIMENTO DANTAS
DATE: 18/11/2024
TIME: 14:30
LOCAL: Videoconferência - Link para acesso: https://meet.google.com/qgc-ppoj-yvs
TITLE:

EVALUATION OF OSTEOGENIC AND GENOTOXIC POTENTIALS OF NANOSTRUCTURED HYDROXYAPATITE-BASED MICROSPHERES CONTAINING ZINC

KEY WORDS:

Stem cell. Genotoxicity. Osteoinduction. Biomaterials.

PAGES: 68
BIG AREA: Ciências Biológicas
AREA: Bioquímica
SUMMARY:

A wide range of biomaterials is being studied as new alternatives in the field of bone regeneration. Among these, hydroxyapatite (HA) is a mineral component present in the inorganic phase of bones. HA is not only biocompatible but also possesses suitable physicochemical properties, allowing for ionic substitutions that enhance its performance for various applications. The REGENERA Institute has developed nanostructured hydroxyapatite (nHA) microspheres with different compositions, including zinc ions (Zn²⁺) incorporation, which are notable for their ability to increase cell viability and promote bone mineralization. However, any modification to HA results in the production of a new biomaterial that, in addition to confirming its osteogenic capabilities, needs to have its biosafety tested. The osteogenic differentiation capacity of nHA-based microspheres containing zinc ions using stroma stem cells isolated from the Wharton's jelly of human umbilical cords (hWJ-MSCs) was evaluated in this study. Cytotoxicity results, assessed by the MTT assay (3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide), indicated that the samples did not significantly reduce the ability of hWJ-MSCs cells to reduce MTT, suggesting that the samples are not cytotoxic under the tested conditions. Results concerning bone mineralization and alkaline phosphatase (ALP) activity indicated that the samples demonstrated osteogenic activity by significantly increasing extracellular matrix mineralization and ALP activity in hWJMSCs cells under the tested conditions. Considering clinical applications, the genotoxic potential of these materials was also assessed. The genotoxicity results, evaluated by the CBMN (cytokinesis-blocked micronucleus) assay and the Comet assay, showed that the samples did not present genotoxic potential under the conditions tested. Thus, we hope that this biomaterial can be applied in bone regeneration

COMMITTEE MEMBERS:
Externo à Instituição - AUGUSTO MONTEIRO DE SOUZA
Externo à Instituição - GILDACIO PEREIRA CHAVES FILHO - USP
Presidente - 1199127 - SILVIA REGINA BATISTUZZO DE MEDEIROS