Lars Eichhorn1, Ramona Dolscheid-Pommerich2, Felix Erdfelder1, Muhammad Ajmal Ayub3, Theresa Schmitz4, Nikos Werner4, Felix Jansen4. 1. Department of Anesthesiology and Intensive Care Medicine, University Hospital of Bonn, Bonn, Germany. 2. Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany. 3. Institute of Physiology 2, University of Bonn, Bonn, Germany. 4. Department of Medicine II, Heart Center Bonn, University Hospital of Bonn, Bonn, Germany.
Abstract
BACKGROUND: Apnea diving has gained worldwide popularity, even though the pathophysiological consequences of this challenging sport on the human body are poorly investigated and understood. This study aims to assess the influence of sustained apnea in healthy volunteers on circulating microparticles (MPs) and microRNAs (miRs), which are established biomarkers reflecting vascular function. HYPOTHESIS: Short intermittent hypoxia due to voluntary breath-holding affects circulating levels of endothelial cell-derived MPs (EMPs) and endothelial cell-derived miRs. METHODS: Under dry laboratory conditions, 10 trained apneic divers performed maximal breath-hold. Venous blood samples were taken, once before and at 4 defined points in time after apnea. Samples were analyzed for circulating EMPs and endothelial miRs. RESULTS: Average apnea time was 329 seconds (±103), and SpO2 at the end of apnea was 79% (±12). Apnea was associated with a time-dependent increase of circulating endothelial cell-derived EMPs and endothelial miRs. Levels of circulating EMPs in the bloodstream reached a peak 4 hours after the apnea period and returned to baseline levels after 24 hours. Circulating miR-126 levels were elevated at all time points after a single voluntary maximal apnea, whereas miR-26 levels were elevated significantly only after 30 minutes and 4 hours. Also miR-21 and miR-92 levels increased, but did not reach the level of significance. CONCLUSIONS: Even a single maximal breath-hold induces acute endothelial activation and should be performed with great caution by subjects with preexisting vascular diseases. Voluntary apnea might be used as a model to simulate changes in endothelial function caused by hypoxia in humans.
BACKGROUND:Apnea diving has gained worldwide popularity, even though the pathophysiological consequences of this challenging sport on the human body are poorly investigated and understood. This study aims to assess the influence of sustained apnea in healthy volunteers on circulating microparticles (MPs) and microRNAs (miRs), which are established biomarkers reflecting vascular function. HYPOTHESIS: Short intermittent hypoxia due to voluntary breath-holding affects circulating levels of endothelial cell-derived MPs (EMPs) and endothelial cell-derived miRs. METHODS: Under dry laboratory conditions, 10 trained apneic divers performed maximal breath-hold. Venous blood samples were taken, once before and at 4 defined points in time after apnea. Samples were analyzed for circulating EMPs and endothelial miRs. RESULTS: Average apnea time was 329 seconds (±103), and SpO2 at the end of apnea was 79% (±12). Apnea was associated with a time-dependent increase of circulating endothelial cell-derived EMPs and endothelial miRs. Levels of circulating EMPs in the bloodstream reached a peak 4 hours after the apnea period and returned to baseline levels after 24 hours. Circulating miR-126 levels were elevated at all time points after a single voluntary maximal apnea, whereas miR-26 levels were elevated significantly only after 30 minutes and 4 hours. Also miR-21 and miR-92 levels increased, but did not reach the level of significance. CONCLUSIONS: Even a single maximal breath-hold induces acute endothelial activation and should be performed with great caution by subjects with preexisting vascular diseases. Voluntary apnea might be used as a model to simulate changes in endothelial function caused by hypoxia in humans.
Authors: Patrick S Mitchell; Rachael K Parkin; Evan M Kroh; Brian R Fritz; Stacia K Wyman; Era L Pogosova-Agadjanyan; Amelia Peterson; Jennifer Noteboom; Kathy C O'Briant; April Allen; Daniel W Lin; Nicole Urban; Charles W Drescher; Beatrice S Knudsen; Derek L Stirewalt; Robert Gentleman; Robert L Vessella; Peter S Nelson; Daniel B Martin; Muneesh Tewari Journal: Proc Natl Acad Sci U S A Date: 2008-07-28 Impact factor: 11.205
Authors: Abdelnaby Khalyfa; Nina Youssefnia; Glen E Foster; Andrew E Beaudin; Zhuanghong Qiao; Vincent Pialoux; Matiram Pun; Patrick J Hanly; Leila Kheirandish-Gozal; Marc J Poulin; David Gozal Journal: Front Neurol Date: 2017-12-22 Impact factor: 4.003