Banca de DEFESA: VLADIMIR GALDINO SABINO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : VLADIMIR GALDINO SABINO
DATE: 28/11/2022
TIME: 16:00
LOCAL: Plataforma Google Meet
TITLE:

EFFECTS OF LOW-LEVEL LASER IRRADIATION ON OSTEOBLASTS CULTURED ON NANOFIBROUS POLYLACTIC ACID SCAFFOLDS

KEY WORDS:

photobiomodulation; bone; bone tissue engineering; polymers.

PAGES: 53
BIG AREA: Ciências da Saúde
AREA: Odontologia
SUMMARY:

Bone tissue engineering is a relevant branch of regenerative medicine and involves the development of scaffolds with composition and architecture favorable to cell integration, in addition to studying factors capable of promoting cell adhesion and proliferation, including chemical and biophysical stimuli. The study aimed to evaluate the use of low-level laser irradiation (LLLI) to promote in vitro biostimulation of osteoblastic cells cultured on polylactic acid (PLA) nanofibrous scaffolds. The scaffolds were produced by the electrospinning technique and characterized in terms of wettability, composition by Fourier transform infrared spectroscopy (FTIR), surface morphology by scanning electron microscopy (SEM), thermogravimetric characterization (TGA), differential scanning calorimetry (DSC) and crystallinity by X-ray diffraction (XRD). The biological assays were conducted with osteoblasts of the OFCOL II lineage cultured on the surface of the scaffolds and submitted or not (control group) to irradiation with InGaAIP diode laser at doses of 1, 4 and 6 J/cm², power of 30 mW, at wavelengths of 660 nm (R, red light) and 780 nm (IR, infrared). After irradiation, the effects of LLLI on osteoblast proliferation were evaluated using the Alamar Blue biochemical method at intervals of 24, 48, and 72h. Cell viability and morphology were analyzed at 72h, using the Live/Dead assay and scanning electron microscopy (SEM), respectively. Data from the Alamar Blue biochemical assay showed more significant cell proliferation in groups R1 and R6, with R6 showing a significantly higher percentage of Alamar reduction compared to the control group at all intervals (p<0.05). Other differences between the control and irradiated groups were found only at intervals of 48h and 72h for R1 and 72h for IR6. The Live/Dead assay revealed an increase in cell viability in the laser-treated groups, significantly higher in the R1 group when compared to the control group. SEM analysis showed adequate interaction between osteoblasts and scaffolds in all groups, with the cell body spreading along the nanofiber axis, with more evident physical contacts being observed through the formation of bonds through filopodia and lamellipodia in groups R1, R6, and IR6, the same ones that exhibited proliferative highlights in the Alamar Blue assay. Taken together, the data from this study showed that LLLT promotes the biostimulation of osteoblasts cultured on PLA nanofibers, which points to its potential use in bone tissue engineering techniques.

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