Transcutaneous intravascular laser irradiation of blood affects plasma metabolites of women

The effectiveness of indirect Intravascular laser irradiation of blood (ILIB) is not fully understood. In this study, we provided a novel experiment that employs metabolomics to investigate the effects of ILIB in women. Twenty-eight volunteers underwent indirect ILIB and had their plasma collected before and after this procedure. The ILIB was applied at the radial artery for 30 min, using low-power photobiomodulation (660 nm), and a power output of 0.1 W. Plasma samples were extracted and analyzed using liquid chromatography—high-resolution mass spectrometry in an untargeted approach. Partial Least Squares Discriminant Analysis revealed 151 molecules with the Variable In Projection score of ≥ 1. From these, 26 were identified. After checking for molecules related to dietary intake, fasting, medication, or part of the human exposome, 15 were affected by ILIB. The abundances of Estradiol 17b-glucuronide 3-sulfate, CAR 14:3, PI 22:6/PGJ2, and CAR 12:1 significantly increased by ILIB, while AcylGlcADG 62:9, Tyrosyl-Glutamine, and CDP-DG 22:3/PGF1 had the contrary effect. ILIB was shown to modulate molecules from different chemical classes, although its impact on plasma metaboloma was minimal. Further research is warranted to fully elucidate the implications of these findings across various metabolic pathways, thus advancing the science surrounding ILIB.