Elevations of Extracellular Vesicles and Inflammatory Biomarkers in Closed Circuit SCUBA Divers

• Published in: International journal of molecular sciences 2023-03, Vol.24 (6), p.5969
• Main Authors: Arya, Awadhesh K, Balestra, Costantino, Bhopale, Veena M, Tuominen, Laura J, Räisänen-Sokolowski, Anne, Dugrenot, Emmanuel, L'Her, Erwan, Bhat, Abid R, Thom, Stephen R
• Format: Article
• Language: English
• Subjects: Actin; Biomarkers; Biomarkers - metabolism; Cell-Derived Microparticles - metabolism; Decompression Sickness - metabolism; Diving; Endothelial cells; Endothelial Cells - metabolism; Exosomes; Extracellular vesicles; Gases; Gelsolin; Humans; Hyperoxia; IL-1β; Inflammation; Leukocytes (neutrophilic); Lipids; Lipophilic; Microglia; Muscle proteins; Neutrophils; Nitric oxide; Nitric-oxide synthase; Nitrogen; Political aspects; Proteins; Rebreathing; Scuba diving; Seawater; Stains & staining; Statistical analysis; Thrombospondin; Vesicles
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms24065969

Blood-borne extracellular vesicles and inflammatory mediators were evaluated in divers using a closed circuit rebreathing apparatus and custom-mixed gases to diminish some diving risks. "Deep" divers ( = 8) dove once to mean (±SD) 102.5 ± 1.2 m of sea water (msw) for 167.3 ± 11.5 min. "Shallow" divers ( = 6) dove 3 times on day 1, and then repetitively over 7 days to 16.4 ± 3.7 msw, for 49.9 ± 11.9 min. There were statistically significant elevations of microparticles (MPs) in deep divers (day 1) and shallow divers at day 7 that expressed proteins specific to microglia, neutrophils, platelets, and endothelial cells, as well as thrombospondin (TSP)-1 and filamentous (F-) actin. Intra-MP IL-1β increased by 7.5-fold ( < 0.001) after day 1 and 41-fold ( = 0.003) at day 7. Intra-MP nitric oxide synthase-2 (NOS2) increased 17-fold ( < 0.001) after day 1 and 19-fold ( = 0.002) at day 7. Plasma gelsolin (pGSN) levels decreased by 73% ( < 0.001) in deep divers (day 1) and 37% in shallow divers by day 7. Plasma samples containing exosomes and other lipophilic particles increased from 186% to 490% among the divers but contained no IL-1β or NOS2. We conclude that diving triggers inflammatory events, even when controlling for hyperoxia, and many are not proportional to the depth of diving.