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Photobiomodulation Therapy Minimizes the DNA Damage in 5FU-Treated Gingival Fibroblasts
Flávia Cristina Perillo Rosin1, Cristina de Paula Novaes1, Anaeliza Figueiredo Dos Santos1
1Pathology Department, School of Dentistry, University of São Paulo, São Paulo, Brazil.
Abstract:
5-Fluoroufacil (5FU) is a chemotherapeutic agent indicated for solid tumors but causes oral mucositis, which can be prevented and treated using photobiomodulation therapy (PBMT). It is unknown whether PBMT modifies DNA damage induced by 5FU in oral cells. The aim of this study was to investigate the effect of PBMT on DNA damage and repair and on oxidative stress in gingival fibroblasts exposed to 5FU. Primary gingival fibroblasts were exposed to 5FU and then treated with a laser (660 nm, 100 mW, 1 W cm-2 , 0.09 cm2 spot area) for three different irradiation times (6, 10 or 20 s). Six-second irradiation decreased DNA damage and lipidic peroxidation. All irradiated groups showed low H2AX levels and increased p53 expression. Ten-second irradiation showed a trend to induce high lipidic peroxidation levels and DNA damage than other irradiation groups. In conclusion, the PBMT effect on DNA damage and repair was dependent on the time irradiation: 6 s-time irradiation (6.6 J cm-2 ) protect gingival fibroblasts from 5FU-related genotoxicity and oxidative stress, whereas 10s- and 20s-time irradiations (11.1 J cm-2 and 22.2 J cm-2 , respectively) increased the risk of DNA damage after the 5FU exposure.
Insights
Photobiomodulation therapy (PBMT) can protect gingival fibroblasts from 5-Fluorouracil (5FU) genotoxicity. Short PBMT irradiation (6 seconds) reduced DNA damage and oxidative stress, while longer durations increased risks.
Area of Science:
- Biomedical Engineering
- Cell Biology
- Oncology
Background:
- 5-Fluorouracil (5FU) is a chemotherapy drug for solid tumors.
- 5FU can cause oral mucositis, a common side effect.
- Photobiomodulation therapy (PBMT) shows potential for preventing and treating oral mucositis.
Purpose of the Study:
- To investigate PBMT's effect on DNA damage and repair in gingival fibroblasts exposed to 5FU.
- To assess PBMT's impact on oxidative stress induced by 5FU.
- To determine if PBMT influences 5FU-induced genotoxicity in oral cells.
Main Methods:
- Primary gingival fibroblasts were exposed to 5FU.
- Cells were treated with a 660 nm laser at varying irradiation times (6, 10, or 20 seconds).
- DNA damage (H2AX), DNA repair (p53), and lipid peroxidation were analyzed.
Main Results:
- 6-second PBMT irradiation significantly decreased DNA damage and lipid peroxidation.
- All PBMT groups exhibited reduced H2AX levels and increased p53 expression.
- 10-second and 20-second PBMT irradiation showed trends toward increased lipid peroxidation and DNA damage.
Conclusions:
- PBMT's effect on DNA damage and repair is irradiation time-dependent.
- A 6-second PBMT irradiation (6.6 J/cm²) protects gingival fibroblasts from 5FU-induced genotoxicity and oxidative stress.
- Longer PBMT irradiation times (10s and 20s) may increase DNA damage risk post-5FU exposure.
