Exploring the effects of low-level laser therapy on fibroblasts and tumor cells following gamma radiation exposure.
J Biophotonics
; 9(11-12): 1157-1166, 2016 12.
Article
em En
| MEDLINE
| ID: mdl-27322660
Ionizing radiation (IR) induces DNA damage and low-level laser therapy (LLLT) has been investigated to prevent or repair detrimental outcomes resulting from IR exposure. Few in vitro studies, however, explore the biological mechanisms underlying those LLLT benefits. Thus, in this work, fibroblasts and tumor cells are submitted to IR with doses of 2.5 Gy and 10 Gy. After twenty-four-h, the cells are exposed to LLLT with fluences of 30 J cm-2 , 90 J cm-2 , and 150 J cm-2 . Cellular viability, cell cycle phases, cell proliferation index and senescence are evaluated on days 1 and 4 after LLLT irradiation. For fibroblasts, LLLT promotes - in a fluence-dependent manner - increments in cell viability and proliferation, while a reduction in the senescence was observed. Regarding tumor cells, no influences of LLLT on cell viability are noticed. Whereas LLLT enhances cell populations in S and G2 /M cell cycle phases for both cellular lines, a decrease in proliferation and increase in senescence was verified only for tumor cells. Putting together, the results suggest that fibroblasts and tumor cells present different responses to LLLT following exposure to gamma-radiation, and these promising results should stimulate further investigations. Senescence of tumor cells and fibroblasts on the 4th day after ionizing radiation (IR) and low-level laser therapy (LLLT) exposures. The number of senescent cells increased significantly for tumor cells (a) while for fibroblasts no increment was observed (b). The blue collor indicates senescence activity.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Senescência Celular
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Exposição à Radiação
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Terapia com Luz de Baixa Intensidade
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Fibroblastos
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Raios gama
Limite:
Humans
Idioma:
En
Revista:
J Biophotonics
Assunto da revista:
BIOFISICA
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Alemanha