Laser biomodulation on L 929 cell culture.
OBJECTIVE
The aim of the present study was to analyze the effects of photobiomodulation using a 904-nm diode laser at two energy densities (6 J/cm(2) and 50 mJ/cm(2)) on L929 fibroblast cells.


BACKGROUND
Low-power laser irradiation (LPLI) is a non-pharmacological resource that induces important in vitro photobiomodulation on cell cultures and tissues.


METHODS
Irradiation was performed for three days at 24-h intervals. After each interval, the cells were stained with MitoTracker Orange and DioC6 dyes to assess the photobiomodulatory effects of irradiation on mitochondrial activity and changes in the endoplasmic reticulum. The MTT assay [3-(4.5-dimethylthiazol-2-yl)-2.5 diphenyltetrazolium bromide] was used to evaluate cell proliferation.


CONCLUSIONS
The fluorescence microscopy assessment of mitochondria and endoplasmic reticulum in cells irradiated with 6 J/cm(2) and 50 mJ/cm(2) demonstrated intense mitochondrial activity, which was confirmed by DioC6 staining. Reticular activity was observed stemming from increased protein synthesis. Photobiomodulation with 50 mJ/cm(2) was slightly higher than with 6 J/cm(2), as demonstrated by fluorescence microscopy results. Photobiomodulation was also time-dependent, with better results 72-h after irradiation.
Universidade Camilo Castelo Branca, Unicastelo, São Paulo, Brazil.
Deise A A
DA
Pires-Oliveira
Rodrigo F
RF
Oliveira
Aline H A
AH
Machado
Renato A
RA
Zângaro
Cristina
C
Pacheco-Soares
D000818:Animals; D002455:Cell Division / Q000528:radiation effects*; D002478:Cells, Cultured; D004721:Endoplasmic Reticulum / Q000528:radiation effects; D005347:Fibroblasts / Q000528:radiation effects; D007834:Lasers; D051379:Mice; D008856:Microscopy, Fluorescence; D008928:Mitochondria / Q000528:radiation effects; D013778:Tetrazolium Salts; D013997:Time Factors
D013778:Tetrazolium Salts