Wang, Tian, Soni, Gonzalez-Lima, Liu (2016) Interplay between up-regulation of cytochrome-c-oxidase and hemoglobin oxygenation induced by near-infrared laser Scientific reports 6() 30540
Photobiomodulation, also known as low-level laser/light therapy (LLLT), refers to the use of red-to-near-infrared light to stimulate cellular functions for physiological or clinical benefits. The mechanism of LLLT is assumed to rely on photon absorption by cytochrome c oxidase (CCO), the terminal enzyme in the mitochondrial respiratory chain that catalyzes the reduction of oxygen for energy metabolism. In this study, we used broadband near-infrared spectroscopy (NIRS) to measure the LLLT-induced changes in CCO and hemoglobin concentrations in human forearms in vivo. Eleven healthy participants were administered with 1064-nm laser and placebo treatments on their right forearms. The spectroscopic data were analyzed and fitted with wavelength-dependent, modified Beer-Lambert Law. We found that LLLT induced significant increases of CCO concentration (Δ[CCO]) and oxygenated hemoglobin concentration (Δ[HbO]) on the treated site as the laser energy dose accumulated over time. A strong linear interplay between Δ[CCO] and Δ[HbO] was observed for the first time during LLLT, indicating a hemodynamic response of oxygen supply and blood volume closely coupled to the up-regulation of CCO induced by photobiomodulation. These results demonstrate the tremendous potential of broadband NIRS as a non-invasive, in vivo means to study mechanisms of photobiomodulation and perform treatment evaluations of LLLT.
光生物调节，也称为低水平激光/光疗法（LLLT），是指使用红至近红外光刺激细胞功能以获取生理或临床益处。 LLLT的机理被认为是依赖于细胞色素C氧化酶（CCO）的光子吸收，CCO是线粒体呼吸链中的末端酶，催化氧的还原以进行能量代谢。在这项研究中，我们使用宽带近红外光谱（NIRS）来测量LLLT诱导的人体前臂中CCO和血红蛋白浓度的变化。 11名健康受试者的右前臂接受了1064 nm激光和安慰剂治疗。对光谱数据进行分析，并与波长相关的修改后的比尔-朗伯定律进行拟合。我们发现随着激光能量剂量随时间累积，LLLT会导致治疗部位的CCO浓度（Δ[CCO]）和含氧血红蛋白浓度（Δ[HbO]）显着增加。在LLLT期间首次观察到Δ[CCO]和Δ[HbO]之间有很强的线性相互作用，这表明氧气供应和血容量的血液动力学反应与光生物调节诱导的CCO上调密切相关。这些结果表明，宽带NIRS作为研究光生物调节机制和进行LLLT治疗评估的非侵入性体内手段具有巨大潜力。