本研究的目的是首次分析使用散焦高功率激光（DHPL）的光生物调节疗法（PBMT）对成肌细胞C2C12的活力和迁移的影响，并将其与低功率激光治疗进行比较。细胞分为9组：假照射10％胎牛血清（FBS）；假照射5％FBS；低功率激光0.1W;DHPL8101W;DHPL8102W;DHPL9801W;DHPL9802W;DHPL双1W;DHPL双2W。为了模拟应激条件，所有暴露于照射的组维持在DMEM5%FBS中。通过磺罗丹明B测定评估治疗对细胞活力的影响，并通过划痕测定和延时评估对细胞迁移的影响。PBMT方案没有改变成肌细胞的活力。所有PBMT方案都能够在第一次照射6和18小时后加速划痕闭合(p<0.001)。此外，迁移速度的提高，使用2W的双波长方案观察到DHPL激光的效果更明显（p<0.001）。总之,本研究中使用的不同PBMT方案加速了C2C12成肌细胞的迁移，2W双波长突出作为最有效的协议测试。用PBMT治疗肌肉损伤的益处似乎与其诱导细胞迁移而对细胞活力没有显著影响的能力有关。
The aim of the present
study was to analyze for the first time the effect of photobiomodulation therapy (PBMT) using defocused high-power laser (DHPL) in myoblast cell line C2C12 viability and migration and compare them with low-power laser therapy. Cells were divided into 9 groups: Sham irradiation 10% fetal bovine serum (FBS); Sham irradiation 5%FBS; low-power laser 0.1 W; DHPL 810 1 W; DHPL 810 2 W; DHPL 980 1 W; DHPL 980 2 W; DHPL dual 1 W; DHPL dual 2 W. To simulate stress conditions, all groups exposed to irradiation were maintained in DMEM 5% FBS. The impact of therapies on cell viability was assessed through sulforhodamine B assay and on cells migration through scratch assays and time-lapse. Myoblast viability was not modified by PBMT protocols. All PBMT protocols were able to accelerate the scratch closure after 6 and 18 h of the first irradiation (p < 0.001). Also, an increase in migration speed, with a more pronounced effect of DHPL laser using dual-wavelength protocol with 2 W was observed (p < 0.001). In conclusion, the diverse PBMT protocols used in this
study accelerated the C2C12 myoblasts migration, with 2-W dual-wavelength outstanding as the most effective protocol tested. Benefits from treating muscle injuries with PBMT appear to be related to its capacity to induce cell migration without notable impact on cell viability.
