Efeitos da fotobiomodulação utilizando diferentes fontes de luz e parâmetros dosimétricos sobre a diferenciação e migração de células precursoras musculares

Abstract

The skeletal muscle tissue shown a high regeneration capacity after injury due the presence of muscular satellite cells (SC). Photobiomodulation (PBM) has demonstrated positive effects during muscle repair process in experimental and clinical studies. The aim of this study was to evaluate the effects of PBM using low-level laser and light emitting diode as light sources and different dosimetric parameters in the differentiation and migration of C2C12 myoblasts. C2C12 myoblasts were cultured in proliferation medium and were analyzed in different groups: (a) LLL control; (b) LLL 40mW; (c) LLL 70mW; (d) LED control; (e) LED 40 mW; (f) LED 70 mW. Cells from groups (b) and (c) were exposed to a single irradiation using an infrared LLL (AsGaAl). Cells from groups (e) and (f) were irradiated with the infrared LED. After irradiation all experimental groups were incubated at 37oC, 5% CO2 for 24, 48 and 72h to evaluated cell differentiation through the fusion index and cell migration using a scratch assay after 6, 12 and 24h of incubation. The results showed that PBM treated C2C12 cells of the 40 mW and 70 mW groups showed an increased fusion index in comparison to the control group after 24 h (40 mW – p <0,01; 70 mW – p <0,001) and 72 h (40 mW – p <0.05; 70 mW – p <0.01), and in the LED experimental groups after 72h only 70 mW had an increased fusion index in comparison to the control group (p<0,05). The results also showed higher cell migration in the PBM treated group using 70 mW in comparison to the control group after 6h (p<0,05) and 24h (p<0.01) and in the 70 mW LED group only after 24h (<0,05). In conclusion, PBM used in different light sources and dosimetric parameters was able to modulate the differentiation of the C2C12 myoblasts verified by the fusion index, but only PBM 70mW was able to modulate their migration.