TY - JOUR T1 - Photobiomodulation at Multiple Wavelengths Differentially Modulates Oxidative Stress and . JF - Oxid Med Cell Longev Y1 - 2018 A1 - Rupel, Katia A1 - Zupin, Luisa A1 - Colliva, Andrea A1 - Kamada, Anselmo A1 - Poropat, Augusto A1 - Ottaviani, Giulia A1 - Gobbo, Margherita A1 - Fanfoni, Lidia A1 - Gratton, Rossella A1 - Santoro, Massimo A1 - Di Lenarda, Roberto A1 - Biasotto, Matteo A1 - Zacchigna, Serena KW - Adult KW - Aged KW - Aged, 80 and over KW - Female KW - Humans KW - Keratinocytes KW - Lasers, Semiconductor KW - Low-Level Light Therapy KW - Male KW - Middle Aged KW - Neutrophils KW - Oxidation-Reduction KW - Oxidative Stress KW - Stomatitis AB -

Photobiomodulation (PBM) is emerging as an effective strategy for the management of multiple inflammatory conditions, including oral mucositis (OM) in cancer patients who receive chemotherapy or radiotherapy. Still, the poor understanding of the mechanisms by which the light interacts with biological tissues and the heterogeneity of light sources and protocols employed worldwide significantly limits its applicability. Reactive oxygen species (ROS) are massively generated during the early phases of OM and play a major role in the pathogenesis of inflammation in general. Here, we report the results of a clinical and experimental study, aimed at evaluating the effect of laser light at different wavelengths on oxidative stress in oncologic patients suffering from OM and in two cell types abundantly present within the inflamed oral mucosa, neutrophil polymorphonuclear (PMN) granulocytes, and keratinocytes. In addition to standard ROS detection methods, we exploited a roGFP2-Orp1 genetically encoded sensor, allowing specific, quantitative, and dynamic imaging of redox events in living cells in response to oxidative stress and PBM. We found that the various wavelengths differentially modulate ROS production. In particular, the 660 nm laser light increases ROS production when applied either before or after an oxidative stimulus. In contrast, the 970 nm laser light exerted a moderate antioxidant activity both in the saliva of OM patients and in both cell types. The most marked reduction in the levels of ROS was detected in cells exposed either to the 800 nm laser light or to the combination of the three wavelengths. Overall, our study demonstrates that PBM exerts different effects on the redox state of both PMNs and keratinocytes depending on the used wavelength and prompts the validation of a multiwavelength protocol in the clinical settings.

VL - 2018 U1 - http://www.ncbi.nlm.nih.gov/pubmed/30534349?dopt=Abstract ER -