Costa do Bomfim Fernando Russo, Gonzalez Sella Valéria Regina, Thomasini Ronaldo Luis, Plapler Hélio
Postgraduate Program in Interdisciplinary Surgical Science, Universidade Federal de São Paulo, Escola Paulista de Medicina, São Paulo, SP, Brazil.
Laboratory of Molecular Biology, Centro Universitário da Fundação Hermínio Ometto - FHO, Araras, SP, Brazil.
J Lasers Med Sci. 2024 Sep 14;15:e45. doi: 10.34172/jlms.2024.45. eCollection 2024.
Photobiomodulation with low-level laser treatment can enhance bone formation by stimulating the cell division of osteoblasts and increasing the amount of protein deposition, thus encouraging the formation of new bone. The aim of this study was to evaluate the effects of photobiomodulation with a low-level laser on proliferation and gene expression related to calcium signaling in human osteoblasts. Osteoblastic cell lines of the hFOB1.19 lineage, human osteoblasts, were grown and assigned into two groups, control (C; n=78 cultured wells) and photobiomodulation (L; n=78 cultured wells) with n=6 per day of the experimental period. Cells were cultured (immature at 34 ºC), and after maturation at 37 ºC, group L cells were exposed to laser irradiation with a low-level laser device (gallium and aluminum arsenide), at a wavelength of 808 nm, a power output of 200 mW, and a power density of 200 mW/cm. The energy delivered to the cells was 37 J/cm, with a beam area of 0.02 mm and an exposure time of 5 seconds. This treatment was applied daily for a period of 13 days. Following this, the number of cells was counted, and RNA was isolated, measured, and then converted into cDNA for further quantification using a comparative Ct method with real-time polymerase chain reaction. The results were then subjected to statistical analysis through a Mann-Whitney test, with a significance level of <0.05. The cell count in the L group (37.25x10±4±22.02) was statistically higher compared to the control group (22.75x10±4±7.660) with a value of 0.0259. The values of 2ΔΔCt for S100A6, plasma membrane calcium ATPase (PMCA), and calmodulin genes indicated hyper-expression on the thirteenth day, while the osteocalcin gene showed hypo-expression. The study suggests that the photobiomodulation mechanism with a low-level laser may regulate gene expression in human osteoblasts in a dose-dependent and cumulative manner.
低强度激光治疗的光生物调节作用可通过刺激成骨细胞的细胞分裂和增加蛋白质沉积量来促进骨形成，从而促进新骨的形成。本研究的目的是评估低强度激光的光生物调节作用对人成骨细胞增殖及与钙信号相关基因表达的影响。培养人成骨细胞系hFOB1.19谱系的成骨细胞，并将其分为两组，对照组（C；n = 78个培养孔）和光生物调节组（L；n = 78个培养孔），实验期间每天每组6个样本。细胞在34℃培养（未成熟），在37℃成熟后，L组细胞用低强度激光设备（砷化镓铝）进行激光照射，波长为808nm，输出功率为200mW，功率密度为200mW/cm²。传递给细胞的能量为37J/cm²，光束面积为0.02mm²，照射时间为5秒。该治疗每天进行，持续13天。之后，对细胞进行计数，提取RNA并进行测量，然后使用实时聚合酶链反应的比较Ct法将其转化为cDNA进行进一步定量。然后通过Mann-Whitney检验对结果进行统计分析，显著性水平<0.05。L组的细胞计数（37.25×10⁴±22.02）与对照组（22.75×10⁴±7.660）相比有统计学差异，P值为0.0259。S100A6、质膜钙ATP酶（PMCA）和钙调蛋白基因的2ΔΔCt值在第13天显示高表达，而骨钙素基因显示低表达。该研究表明，低强度激光的光生物调节机制可能以剂量依赖和累积的方式调节人成骨细胞中的基因表达。
