Transcutaneous intravascular laser irradiation of blood affects plasma metabolites of women

Abstract

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.

Keywords: Inflammation; Mass spectrometry; Photobiomodulation.

Fig. 1

Experimental design of the study. During the first visit, researchers provided an explanation of the procedure, assessed the eligibility, and collected blood from the participants. During the second visit, after a standard breakfast, the indirect intravascular laser irradiation of blood (ILIB) application took place. Before and after the ILIB, blood samples were collected for metabolomic analyses.

Fig. 2

Flow diagram of the recruitment, excluded, and the included volunteers.

Fig. 3

2-D scores plot (A) of the Partial Least Squares Discriminant Analysis (PLS-DA) regarding the molecules detected before and after the Intravascular Laser Irradiation of Blood (ILIB); (B) cross-validation of the model; (C) Loadings plot. Each point on the loadings plot represents a metabolite. Metabolites that increased following the ILIB may be depicted by points positioned towards one end of the y-axis (latent component), while metabolites that decreased may be depicted by points positioned towards the other end.

Fig. 4

Paired sample t-tests of the molecules that increased after the Intravascular Laser Irradiation of Blood (ILIB) by the Partial Least Squares Discriminant Analysis (PLS-DA). (A) Estradiol 17b-glucuronide 3-sulfate; (B) CAR 14:3; (C) PI 22:6/PGJ2; (D) LPG 20:1; (E) CAR 12:1; (F) CAR 14:1; (G) Palmitoyl Glycine; (H) Aminobutyric acid; (I) FA 16:1; CAR Acylcarnitine, PI phosphatidylinositol, LPG lysophosphatidylglycerol, FA fatty acid .p-value was corrected by the False Discovery Rate; *p < 0.05.

Fig. 5

Paired sample t-tests of the molecules that decreased after the Intravascular Laser Irradiation of Blood (ILIB) by the Partial Least Squares Discriminant Analysis (PLS-DA). (A) AcylGlcADG 62:9; (B) Tyrosyl-Glutamine; (C) LPE 18:0; (D) CDP-DG 22:3/PGF1; (E) FA 6:2; (F) Tryptophol; FA Fatty Acid, AcylGlcADG acylated glucosyl acyl diacylglycerol, LPE lysophosphatidylethanolamine, CDP-DG cytidine diphosphate-diacylglycerol; p-value was corrected by the False Discovery Rate; *p < 0.05.

Fig. 6

Machine learning algorithms for classification of the differential molecules between before and after Intravascular Laser Irradiation of Blood (ILIB); (A) Support Vector Machine; (B) Random Forest