Banca de DEFESA: CAROLINE MEDEIROS LAFFITTE

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : CAROLINE MEDEIROS LAFFITTE
DATE: 31/05/2024
TIME: 14:00
LOCAL: Plataforma Google Meet
TITLE:

EFFECT OF NUTRITIONAL CONDITION AND PHOTOBIOMODULATION PROTOCOL ON THE IN VITRO VIABILITY AND PROLIFERATION OF MURINE PRE-OSTEOBLASTIC CELLS

KEY WORDS:

Cell culture; osteoblasts; laser; cell proliferation.

PAGES: 62
BIG AREA: Ciências da Saúde
AREA: Odontologia
SUMMARY:

Low-level laser irradiation (LLLI) has been used to stimulate in vitro proliferation in various cell types. However, certain aspects of experimental protocols, particularly those related to cell culture and irradiation protocols, still require standardization. This study aimed to assess the impact of nutritional conditions and irradiation parameters on the viability and proliferation of murine pre-osteoblasts. Cells from the MC3T3-E1 lineage were plated under normal cultivation conditions (αMEM medium supplemented with 10% fetal bovine serum) or nutritional deprivation (αMEM medium without serum) and they were then either irradiated or kept as controls. The InGaAlP diode laser was used at wavelengths of 660 nm (red) or 790 nm (infrared), with doses of 1, 4, or 6 J/cm², in a single dose in continuous mode of action. Cell viability and proliferation were evaluated at 24, 48, and 72 h post-irradiation, using the Alamar blue reduction assay. Additionally, the cell cycle and events related to cell death were assessed through propidium iodide (PI) labeling and Annexin V/PI assay, respectively, using flow cytometry. Results of Alamar blue assay showed that cells cultured under normal nutrition (10% FBS) showed no significant difference (p>0.05) in cell viability and proliferation across different irradiation protocols. However, under nutritional deprivation (without FBS), the infrared laser at a dose of 6 J/cm² significantly increased (p<0.05) cell viability and proliferation compared to the control group within 72 hours. These findings were confirmed by assays evaluating the cell cycle and cell death events (Annexin V/PI). Taken together, these results suggest that in vitro photobiomodulation leads to more consistent outcomes in bone cells exposed to stress conditions. Consequently, it is crucial to accurately simulate these conditions in studies involving laser therapy with in vitro models of bone diseases and in experiments related to photobiomodulation for bone tissue engineering.

COMMITTEE MEMBERS:
Presidente - 2220417 - CARLOS AUGUSTO GALVAO BARBOZA
Interna - 1298808 - MARCIA CRISTINA DA COSTA MIGUEL
Externo à Instituição - CARLOS EDUARDO BEZERRA DE MOURA - UFERSA