Ateş Gamze Bölükbaşı, Ak Ayşe, Garipcan Bora, Gülsoy Murat
Institute of Biomedical Engineering, Bogazici University, Uskudar, 34684, Istanbul, Turkey.
Engineering Faculty, Biomedical Engineering, Erzincan University, 24100, Erzincan, Turkey.
Lasers Med Sci. 2018 Sep;33(7):1591-1599. doi: 10.1007/s10103-018-2530-9. Epub 2018 May 9.
Photobiomodulation (PBM) and photodynamic therapy (PDT) share similar mechanisms but have opposite aims. Increased levels of reactive oxygen species (ROS) in the target tissue in response to light combined photosensitizer (PS) application may lead to cell proliferation or oxidative damage depending on the ROS amount. The purpose of the present study is to investigate the effect of indocyanine green (ICG)-mediated PBM on osteoblast cells by measuring cell viability, proliferation, alkaline phosphatase (ALP) activity, mineralization, and gene expressions of three phenotypic osteoblast markers. A diode laser irradiating at 809 nm (10 W output power, 50 mW/cm power density) was used at 0.5, 1, and 2 J/cm energy densities (10, 20, and 40 s respectively) was applied following ICG incubation. No inhibitory effect was observed in cell viability and proliferation according to the (4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and Alamar Blue assays. ICG-mediated PBM did not alter cell viability but increased ALP activity and enhanced mineralization of existing osteoblasts. These results were also confirmed by real-time polymerase chain reaction (RT-PCR) analysis of osteoblastic markers. PS can be combined to PBM not only to damage the malignant cells as aimed in PDT studies, but also to promote cellular activity. The findings of this in vitro study may contribute to in vivo studies and ICG-mediated PBM can have promising outcomes in bone healing and regeneration therapies in future.
光生物调节作用（PBM）和光动力疗法（PDT）具有相似的机制，但目的相反。在光照联合应用光敏剂（PS）后，靶组织中活性氧（ROS）水平升高，根据ROS的量，可能导致细胞增殖或氧化损伤。本研究的目的是通过测量细胞活力、增殖、碱性磷酸酶（ALP）活性、矿化以及三种成骨细胞表型标志物的基因表达，来研究吲哚菁绿（ICG）介导的PBM对成骨细胞的影响。在ICG孵育后，使用波长为809 nm的二极管激光器（输出功率10 W，功率密度50 mW/cm²），分别以0.5、1和2 J/cm²的能量密度（分别为10、20和40秒）进行照射。根据（4,5-二甲基噻唑-2-基）-2,5-二苯基溴化四氮唑（MTT）和alamar蓝检测，未观察到对细胞活力和增殖的抑制作用。ICG介导的PBM没有改变细胞活力，但增加了ALP活性并增强了现有成骨细胞的矿化。这些结果也通过成骨细胞标志物的实时聚合酶链反应（RT-PCR）分析得到证实。PS不仅可以与PBM联合用于如PDT研究中那样损伤恶性细胞，还可以促进细胞活性。这项体外研究的结果可能有助于体内研究，并且ICG介导的PBM在未来的骨愈合和再生治疗中可能会有良好的结果。
