Photo-induced neutrophil extracellular traps: The role of cytochromes

Abstract

Neutrophils play an important role in the pathogenesis of inflammatory, autoimmune, and oncological diseases. In this study, we investigated the role of radiation in a wide range of wavelengths, from UV-A to red visible light, based on the concept of photoacceptance by two cytochromes: cytochrome_b558 and cytochrome_c oxidase. Raman spectroscopy was applied to record characteristic Raman frequencies of various reactive oxygen species (ROS), and low-frequency lattice vibrational modes for citrulline. Using selective inhibitors of NADPH oxidase (apocynin) and PAD4 (GSK484), it was established that exposure of neutrophils to light of different wavelengths activates signaling pathway of NETs formation via NADPH oxidase and PAD4. We recorded sharp peaks of ROS and citrulline in the process of neutrophil irradiation, indicating the involvement of intracellular ROS during light exposure. In conclusion, we believe that the development of new drugs designed to suppress NETs can lead to the inhibition of the NET formation at sites of UV and visible light exposure and, as a result, to decrease in the symptoms of UV-induced photoaging and other organ damage.