Photobiomodulation at Defined Wavelengths Regulates Mitochondrial Membrane Potential and Redox Balance in Skin Fibroblasts

Figure 1

LED device and irradiation characterization. (a) Simple collimator. (b) Lens arrangement inside the collimator. (c) Cross section of the LED emitter. (d) Exposure protocol: 24 hr after seeding, cells were exposed to the red 645 nm light for 20 s. Exposure was performed in the center of the well only. After 24 hr, cells were stained with the MitoTracker fluorescent dye and fixed. (e) Representative pictures of cells stained with MitoTracker at the center of the well, where cells were directly exposed to the light, and at the edge of the well, where cells were not exposed to the light. Scale bar: 50 µm. (f) The graph shows the relative MitoTracker intensity, and results are expressed as the percentage of the cells directly exposed to light at the center of the well (100%; white bar and dotted line); n = 3. Statistical analysis. Data are presented as average values ± SEM. Student’s t-test was used to compare the MitoTracker intensity in the centre of the well (directly exposed to light) to the edge of each well (not exposed to light).