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Elia A, Barlow MJ, Lees MJ, Petri G, Keramidas ME. Stress biomarker changes following a series of repeated static and dynamic apneas in non-divers. Respir Physiol Neurobiol 2024; 323:104228. [PMID: 38309488 DOI: 10.1016/j.resp.2024.104228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 01/18/2024] [Accepted: 01/25/2024] [Indexed: 02/05/2024]
Abstract
PURPOSE This study examined the magnitude of physiological strain imposed by repeated maximal static and dynamic apneas through assessing a panel of stress-related biomarkers. METHODS Eleven healthy men performed on three separate occasions (≥72-h apart): a series of five repeated maximal (i) static (STA) or (ii) dynamic apneas (DYN) or (iii) a static eupneic protocol (CTL). Venous blood samples were drawn at 30, 90, and 180-min after each protocol to determine ischaemia modified albumin (IMA), neuron-specific enolase (NSE), myoglobin, and high sensitivity cardiac troponin T (hscTnT) concentrations. RESULTS IMA was elevated after the apnoeic interventions (STA,+86%;DYN,+332%,p ≤ 0.047) but not CTL (p = 0.385). Myoglobin was higher than baseline (23.6 ± 3.9 ng/mL) 30-min post DYN (+70%,38.8 ± 13.3 ng/mL,p = 0.030). A greater myoglobin release was recorded in DYN compared with STA and CTL (p ≤ 0.035). No changes were observed in NSE (p = 0.207) or hscTnT (p = 0.274). CONCLUSIONS Five repeated maximal DYN led to a greater muscle injury compared with STA but neither elicited myocardial injury or neuronal-parenchymal damage.
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Affiliation(s)
- Antonis Elia
- Division of Environmental Physiology, KTH Royal Institute of Technology, Stockholm, Sweden.
| | - Matthew J Barlow
- Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom
| | - Matthew J Lees
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, Ontario, Canada
| | - Georgios Petri
- Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom
| | - Michail E Keramidas
- Division of Environmental Physiology, KTH Royal Institute of Technology, Stockholm, Sweden
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Lawton SB, Grobe CC, Reho JJ, Raff H, Thulin JD, Jensen ES, Burnett CM, Segar JL, Grobe JL. Differences in Fluid, Electrolyte, and Energy Balance in C57BL/6J Mice ( Mus musculus) in Metabolic Caging at Thermoneutral or Standard Room Temperatures. JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE : JAALAS 2024; 63:190-200. [PMID: 38191147 PMCID: PMC11022944 DOI: 10.30802/aalas-jaalas-23-000091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 10/16/2023] [Accepted: 12/15/2023] [Indexed: 01/10/2024]
Abstract
The Guide for the Care and Use of Laboratory Animals recommends mice be pair or group housed and provided with nesting materials. These provisions support social interactions and are also critical for thermoregulatory behaviors such as huddling and burrowing. However, studies of fluid and electrolyte balance and digestive function may involve use of metabolic caging (MC) systems in which mice are housed individually on wire-mesh floors that permit quantitative collection of urine and feces. MC housing prevents mice from performing their typical huddling and burrowing behaviors. Housing in MC can cause weight loss and behavioral changes in rodents. Here, we tested the hypothesis that MC housing of mice at standard room temperature (SRT, 22 to 23 °C) exposes them to cold stress, which causes metabolic changes in the mice as compared with standard housing. We hypothesized that performing MC studies at a thermoneutral temperature (TNT, 30 °C) would minimize these changes. Fluid, electrolyte, and energy balance and body composition were assessed in male and female C57BL/6J mice housed at SRT or TNT in MC, static microisolation cages, or a multiplexed metabolic phenotyping system designed to mimic static microisolation cages (Promethion, Sable Systems International). In brief, as compared with MC housing at SRT, MC housing at TNT was associated with lower food intake and energy expenditure, absence of weight loss, and lower urine and fecal corticosterone levels. These results indicate that housing in MC at SRT causes cold stress that can be mitigated if MC studies are performed at TNT.
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Affiliation(s)
- Samuel Br Lawton
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Connie C Grobe
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - John J Reho
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin; Comprehensive Rodent Metabolic Phenotyping Core, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Hershel Raff
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin; Division of Endocrinology and Molecular Medicine, Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin; Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin; Department of Surgery, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Joseph D Thulin
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin; Research Office Biomedical Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Eric S Jensen
- Department of Pediatrics, Research Office Biomedical Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Colin Ml Burnett
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin; Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin; Division of Cardiovascular Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin; Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Jeffrey L Segar
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin; Department of Pediatrics; Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Justin L Grobe
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin; Comprehensive Rodent Metabolic Phenotyping Core, Medical College of Wisconsin, Milwaukee, Wisconsin; Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin; Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, Wisconsin; Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin;,
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Njire Braticevic M, Zarak M, Simac B, Perovic A, Dumic J. Effects of recreational SCUBA diving practiced once a week on neurohormonal response and myokines-mediated communication between muscles and the brain. Front Cardiovasc Med 2023; 10:1074061. [PMID: 37063956 PMCID: PMC10090300 DOI: 10.3389/fcvm.2023.1074061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 03/02/2023] [Indexed: 03/30/2023] Open
Abstract
ObjectiveDuring physical activity, activation of muscular, endocrine, and nervous systems, results in intensive crosstalk between muscles and other organs, which enables response to physiological stress. In SCUBA diving, extreme environmental conditions represent an additional challenge for homeostasis maintenance, but underlying mechanisms are largely unknown. We aimed to contribute to the understanding of neurohormonal response and muscle-brain crosstalk by measuring the concentrations of the selected hormones secreted by the pituitary-target organ axis and myokines involved in the muscle-brain endocrine loop in recreational SCUBA (rSCUBA) divers.MethodsFourteen male divers performed five open-water recreational dives (one per week, depth of 20–30 m, lasting 30 min, between 9 and 10 am), after a winter non-diving period of 5 months. Blood samples were collected immediately before and after the first, third, and fifth dives. Adrenocorticotropic hormone (ACTH), cortisol, thyroid-stimulating hormone (TSH), free thyroxine (fT4), prolactin, total testosterone, growth hormone (GH), insulin-like growth factor-1 (IGF-1), irisin, brain-derived neurotrophic factor (BDNF), S100B, glial fibrillary acidic protein (GFAP), and neuron-specific enolase (NSE) were measured using commercially available immunoassays.ResultsCortisol and ACTH levels decreased after every dive, while total testosterone decreased only after the first dive. No significant changes in post-dive values, as well as the cumulative effect on any other measured hormone, were observed. Although irisin and BDNF levels decreased after the first and third dives, the fifth dive caused a significant increase in both myokines. Changes in IGF-1 levels were not observed. All three dives caused a significant increase in S100B levels. A statistically significant decrease in GFAP concentration was observed after every dive, while NSE pre-dive concentration declined over the studied period. The cumulative effect on myokine levels was reflected in a continuous decline in irisin and BDNF pre-dive levels throughout the studied period, but an increasing trend after the fifth dive was observed.ConclusionsObserved changes in myokines and hormone levels point to a specific response to rSCUBA practiced once a week, most likely due to extreme environmental conditions. Further studies on communication between muscles and other organ systems, particularly on the muscle-brain endocrine loop, are required for a deeper understanding of the adaptation mechanisms to this kind of physiological stress.
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Affiliation(s)
- Marina Njire Braticevic
- Department of Laboratory Diagnostics, Dubrovnik General Hospital, Dubrovnik, Croatia
- Correspondence: Marina Njire Braticevic
| | - Marko Zarak
- Clinical Department for Laboratory Diagnostics, Dubrava University Hospital, Zagreb, Croatia
- Faculty of Pharmacy and Biochemistry, University of Zagreb, Zagreb, Croatia
| | - Brankica Simac
- Clinical Department for Laboratory Diagnostics, Dubrava University Hospital, Zagreb, Croatia
| | - Antonija Perovic
- Department of Laboratory Diagnostics, Dubrovnik General Hospital, Dubrovnik, Croatia
| | - Jerka Dumic
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy and Biochemistry, University of Zagreb, Zagreb, Croatia
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Cialoni D, Brizzolari A, Sponsiello N, Lancellotti V, Bosco G, Marroni A, Barassi A. Serum Amino Acid Profile Changes After Repetitive Breath-Hold Dives: A Preliminary Study. SPORTS MEDICINE - OPEN 2022; 8:80. [PMID: 35723766 PMCID: PMC9209628 DOI: 10.1186/s40798-022-00474-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 06/06/2022] [Indexed: 12/04/2022]
Abstract
Background The aim of this work was to investigate the serum amino acid (AA) changes after a breath-hold diving (BH-diving) training session under several aspects including energy need, fatigue tolerance, nitric oxide (NO) production, antioxidant synthesis and hypoxia adaptation. Twelve trained BH-divers were investigated during an open sea training session and sampled for blood 30 min before the training session, 30 min and 4 h after the training session. Serum samples were assayed for AA changes related to energy request (alanine, histidine, isoleucine, leucine, lysine, methionine, proline threonine, valine), fatigue tolerance (ornithine, phenylalanine, tyrosine), nitric oxide production (citrulline), antioxidant synthesis (cystine, glutamate, glycine) and hypoxia adaptation (serine, taurine). Main results Concerning the AA used as an energy support during physical effort, we found statistically significant decreases for all the investigated AA at T1 and a gradual return to the basal value at T2 even if alanine, proline and theonine still showed a slight significant reduction at this time. Also, the changes related to the AA involved in tolerance to physical effort showed a statistically significant decrease only at T1 respect to pre-diving value and a returned to normal value at T2. Citrulline, involved in NO production, showed a clear significant reduction both at T1 and T2. Concerning AA involved in endogenous antioxidant synthesis, the behaviour of the three AA investigated is different: we found a statistically significant increase in cystine both at T1 and T2, while glycine showed a statistically significant reduction (T1 and T2). Glutamate did not show any statistical difference. Finally, we found a statistically significant decrease in the AA investigated in other hypoxia conditions serine and taurine (T1 and T2). Conclusions Our data seem to indicate that the energetic metabolic request is in large part supported by AA used as substrate for fuel metabolism and that also fatigue tolerance, NO production and antioxidant synthesis are supported by AA. Finally, there are interesting data related to the hypoxia stimulus that indirectly may confirm that the muscle apparatus works under strong exposure conditions notwithstanding the very short/low intensity of exercise, due to the intermittent hypoxia caused by repetitive diving.
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5
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Kelly KR, Arrington LJ, Bernards JR, Jensen AE. Prolonged Extreme Cold Water Diving and the Acute Stress Response During Military Dive Training. Front Physiol 2022; 13:842612. [PMID: 35874531 PMCID: PMC9304957 DOI: 10.3389/fphys.2022.842612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 06/14/2022] [Indexed: 11/13/2022] Open
Abstract
Introduction: Cold water exposure poses a unique physiological challenge to the human body. Normally, water submersion increases activation of parasympathetic tone to induce bradycardia in order to compensate for hemodynamic shifts and reduce oxygen consumption by peripheral tissues. However, elevated stress, such as that which may occur due to prolonged cold exposure, may shift the sympatho-vagal balance towards sympathetic activation which may potentially negate the dive reflex and impact thermoregulation. Objective: To quantify the acute stress response during prolonged extreme cold water diving and to determine the influence of acute stress on thermoregulation. Materials and Methods: Twenty-one (n = 21) subjects tasked with cold water dive training participated. Divers donned standard diving equipment and fully submerged to a depth of ≈20 feet, in a pool chilled to 4°C, for a 9-h training exercise. Pre- and post-training measures included: core and skin temperature; salivary alpha amylase (AA), cortisol (CORT), osteocalcin (OCN), testosterone (TEST) and dehydroepiandosterone (DHEA); body weight; blood glucose, lactate, and ketones. Results: Core, skin, and extremity temperature decreased (p < 0.001) over the 9-h dive; however, core temperature was maintained above the clinical threshold for hypothermia and was not correlated to body size (p = 0.595). There was a significant increase in AA (p < 0.001) and OCN (p = 0.021) and a significant decrease in TEST (p = 0.003) over the duration of the dive. An indirect correlation between changes in cortisol concentrations and changes in foot temperature (ρ = -0.5,p = 0.042) were observed. There was a significant positive correlation between baseline OCN and change in hand temperature (ρ = 0.66, p = 0.044) and significant indirect correlation between changes in OCN concentrations and changes in hand temperature (ρ = -0.59, p = 0.043). Conclusion: These data suggest that long-duration, cold water diving initiates a stress response—as measurable by salivary stress biomarkers—and that peripheral skin temperature decreases over the course of these dives. Cumulatively, these data suggest that there is a relationship between the acute stress response and peripheral thermoregulation.
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Affiliation(s)
- Karen R. Kelly
- Applied Translational Exercise and Metabolic Physiology Team, Warfighter Performance, Naval Health Research Center, San Diego, CA, United States
- *Correspondence: Karen R. Kelly,
| | - Laura J. Arrington
- Applied Translational Exercise and Metabolic Physiology Team, Warfighter Performance, Naval Health Research Center, San Diego, CA, United States
- Leidos, Inc., San Diego, CA, United States
| | - Jake R. Bernards
- Applied Translational Exercise and Metabolic Physiology Team, Warfighter Performance, Naval Health Research Center, San Diego, CA, United States
- Leidos, Inc., San Diego, CA, United States
| | - Andrew E. Jensen
- Applied Translational Exercise and Metabolic Physiology Team, Warfighter Performance, Naval Health Research Center, San Diego, CA, United States
- Leidos, Inc., San Diego, CA, United States
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6
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Zec M, Antičević V, Lušić Kalcina L, Valić Z, Božić J. Psychophysiological stress response in SCUBA divers: The contribution of negative automatic thoughts and negative emotions. CURRENT PSYCHOLOGY 2022. [DOI: 10.1007/s12144-022-02900-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AbstractThe research questions in this study were to examine the contribution of negative automatic thoughts and negative emotions, measured by two newly-constructed questionnaires, to psychophysiological stress responses among more experienced military and less experienced recreational divers. Further, we examined whether daily variations in cortisol levels could be attributed to the impact of negative thoughts/emotions rather than diving experience. Altogether 15 recreational and 14 military male divers participated in the dive wherein stress responses were measured by anxiety measures (DASS-21 and STAI) and cortisol salivary concentrations. The results of factor analysis and principal component analysis demonstrated acceptable construct validity and internal consistency of both questionanires. Recreational and military divers did not differ significantly in the proportion of negative thoughts and emotions, while recreational divers had significantly higher levels of cortisol release after awakening and immediately before/after diving, indicating their more intense stress responses. A significant interaction between daily variations in cortisol secretion and negative emotions indicated a greater importance of emotions in response to diving stress rather than diving experience. Accordingly, using a multiple regression analysis showed that more pre-diving negative emotions predicted higher levels of pre-diving anxiety and depression as well as more cortisol release. More negative thoughts predicted higher levels of depressive symptoms, while belonging to a group of recreational divers was a significant predictor of higher pre-diving anxiety. This study points to the importance of considering cognitive and emotional experiences, particularly in recreational divers, for the purpose of prevention of negative psychophysiological stress responses prior to diving.
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Dolscheid-Pommerich RC, Stoffel-Wagner B, Fimmers R, Eichhorn L. Changes in hormones after apneic hypoxia/hypercapnia - an investigation in voluntary apnea divers. Respir Physiol Neurobiol 2022; 298:103845. [PMID: 35041989 DOI: 10.1016/j.resp.2022.103845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 01/11/2022] [Accepted: 01/13/2022] [Indexed: 10/19/2022]
Abstract
BACKGROUND Prolonged apnea is characterized by hypoxia/hypercapnia. Hypoxia can be associated with hormonal dysfunction. We raised the question as to whether steroid hormonal and gonadotropin levels could be influenced by short-term hypoxia/hypercapnia in a model of dry apnea in trained apnea divers. METHODS Adrenal, sex steroid and pituitary hormones were measured in ten trained voluntary apnea divers before, immediately after, 0.5 h and 4 h after a maximal breath-hold. Apnea was carried out under dry conditions. RESULTS Corticosterone, progesterone, cortisol, 17-OH-progesterone, dehydroepiandrosterone and androstenedione showed a significant continuous increase with a maximum at 0.5 h after apnea, followed by a decrease back to or below baseline at 4 h after apnea. Testosterone, estradiol, cortisone and dihydrotestosterone showed a decrease 4 h after apnea. Dehydroepiandrosteronesulfate, luteinizing hormone (LH) and follicle stimulating hormone (FSH) showed no significant changes. CONCLUSION Even a single apnea resulted in two different patterns of hormone response to apnea, with increased adrenal and reduced sex steroid levels, while LH/FSH showed no clear kinetic reaction. Apnea divers might be a suitable clinical model for hypoxic disease.
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Affiliation(s)
- R C Dolscheid-Pommerich
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany.
| | - B Stoffel-Wagner
- Department of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - R Fimmers
- Institute for Medical Biometry, Informatics and Epidemiology, University Hospital Bonn, Bonn, Germany
| | - L Eichhorn
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Bonn, Bonn, Germany
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Marlinge M, Chefrour M, Billaut F, Zavarro M, Rostain JC, Coulange M, Guieu R, Joulia F. Blood Adenosine Increase During Apnea in Spearfishermen Reinforces the Efficiency of the Cardiovascular Component of the Diving Reflex. Front Physiol 2021; 12:743154. [PMID: 34675819 PMCID: PMC8523798 DOI: 10.3389/fphys.2021.743154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Accepted: 09/16/2021] [Indexed: 11/13/2022] Open
Abstract
The physiopathology consequences of hypoxia during breath-hold diving are a matter of debate. Adenosine (AD), an ATP derivative, is suspected to be implicated in the adaptive cardiovascular response to apnea, because of its vasodilating and bradycardic properties, two clinical manifestations observed during voluntary apnea. The aim of this study was to evaluate the adenosine response to apnea-induced hypoxia in trained spearfishermen (SFM) who are used to perform repetitive dives for 4-5 h. Twelve SFM (11 men and 1 woman, mean age 41 ± 3 years, apnea experience: 18 ± 9 years) and 10 control (CTL) subjects (age 44 ± 7 years) were enrolled in the study. Subjects were asked to main a dry static apnea and stopped it when they began the struggle phase (average duration: SFM 120 ± 78 s, CTL 78 ± 12 s). Capillary blood samples were collected at baseline and immediately after the apnea and analyzed for standard parameters and adenosine blood concentration ([AD]b). Heart rate (HR), systolic (SBP), and diastolic (DBP) blood pressures were also recorded continuously during the apnea. During the apnea, an increase in SBP and DBP and a decrease in HR were observed in both SFM and CTL. At baseline, [AD]b was higher in SFM compared with CTL (1.05 ± 0.2 vs. 0.73 ± 0.11 μM, p < 0.01). [AD]b increased significantly at the end of the apnea in both groups, but the increase was significantly greater in SFM than in controls (+90.4 vs. +12%, p < 0.01). Importantly, in SFM, we also observed significant correlations between [AD]b and HR (R = -0.8, p = 0.02), SpO2 (R = -0.69, p = 0.01), SBP (R = -0.89, p = 0.02), and DBP (R = -0.68, p = 0.03). Such associations were absent in CTL. The adenosine release during apnea was associated with blood O2 saturation and cardiovascular parameters in trained divers but not in controls. These data therefore suggest that adenosine may play a major role in the adaptive cardiovascular response to apnea and could reflect the level of training.
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Affiliation(s)
- Marion Marlinge
- C2VN, Center for Cardiovascular and Nutrition Research, INSERM 1263, INRAE 1260, Aix Marseille University, Marseille, France.,Laboratory of Biochemistry, Timone Hospital, Marseille, France
| | | | | | | | - Jean-Claude Rostain
- C2VN, Center for Cardiovascular and Nutrition Research, INSERM 1263, INRAE 1260, Aix Marseille University, Marseille, France
| | - Mathieu Coulange
- C2VN, Center for Cardiovascular and Nutrition Research, INSERM 1263, INRAE 1260, Aix Marseille University, Marseille, France.,Department of Hyperbaric Medicine, Hospital Sainte Marguerite, Marseille, France
| | - Régis Guieu
- C2VN, Center for Cardiovascular and Nutrition Research, INSERM 1263, INRAE 1260, Aix Marseille University, Marseille, France.,Laboratory of Biochemistry, Timone Hospital, Marseille, France
| | - Fabrice Joulia
- C2VN, Center for Cardiovascular and Nutrition Research, INSERM 1263, INRAE 1260, Aix Marseille University, Marseille, France.,UFR STAPS, Toulon University, La Garde, France
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Bao XC, Shen Q, Fang YQ, Wu JG. Human Physiological Responses to a Single Deep Helium-Oxygen Diving. Front Physiol 2021; 12:735986. [PMID: 34650446 PMCID: PMC8510140 DOI: 10.3389/fphys.2021.735986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Accepted: 09/06/2021] [Indexed: 11/13/2022] Open
Abstract
Objective: The objective of this study was to explore whether a single deep helium-oxygen (heliox) dive affects physiological function. Methods: A total of 40 male divers performed an open-water heliox dive to 80 m of seawater (msw). The total diving time was 280 min, and the breathing helium-oxygen time was 20 min. Before and after the dive, blood and saliva samples were collected, and blood cell counts, cardiac damage, oxidative stress, vascular endothelial activation, and hormonal biomarkers were assayed. Results: An 80 msw heliox dive induced a significant increase in the percentage of granulocytes (GR %), whereas the percentage of lymphocytes (LYM %), percentage of intermediate cells (MID %), red blood cell number (RBC), hematocrit (hCT), and platelets (PLT) decreased. During the dive, concentrations of creatine kinase (CK), a myocardial-specific isoenzyme of creatine kinase (CK-MB) in serum and amylase alpha 1 (AMY1), and testosterone levels in saliva increased, in contrast, IgA levels in saliva decreased. Diving caused a significant increase in serum glutathione (GSH) levels and reduced vascular cell adhesion molecule-1 (VCAM-1) levels but had no effect on malondialdehyde (MDA) and endothelin-1 (ET-1) levels. Conclusion: A single 80 msw heliox dive activates the endothelium, causes skeletal-muscle damage, and induces oxidative stress and physiological stress responses, as reflected in changes in biomarker concentrations.
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Affiliation(s)
- Xiao-Chen Bao
- Department of Diving and Hyperbaric Medicine, Naval Medical Center, Shanghai, China
| | - Quan Shen
- Department of Hyperbaric Medicine, Naval Hospital of Eastern Theater, Zhejiang, China
| | - Yi-Qun Fang
- Department of Diving and Hyperbaric Medicine, Naval Medical Center, Shanghai, China
| | - Jian-Guo Wu
- Department of Hyperbaric Medicine, Naval Hospital of Eastern Theater, Zhejiang, China
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Elia A, Woods DR, Barlow MJ, Lees MJ, O'Hara JP. Cerebral, cardiac and skeletal muscle stress associated with a series of static and dynamic apnoeas. Scand J Med Sci Sports 2021; 32:233-241. [PMID: 34597427 DOI: 10.1111/sms.14067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 09/21/2021] [Accepted: 09/28/2021] [Indexed: 11/29/2022]
Abstract
PURPOSE This study sought to explore, for the first time, the effects of repeated maximal static and dynamic apnoeic attempts on the physiological milieu by assessing cerebral, cardiac and striatal muscle stress-related biomarkers in a group of elite breath-hold divers (EBHD). METHODS Sixteen healthy males were recruited (EBHD = 8; controls = 8). On two separate occasions, EBHD performed two sets of five repeated maximal static apnoeas (STA) or five repeated maximal dynamic apnoeas (DYN). Controls performed a static eupnoeic protocol to negate any effects of water immersion and diurnal variation on haematology (CTL). Venous blood samples were drawn at 30, 90, and 180 min after each protocol to determine S100β, neuron-specific enolase (NSE), myoglobin, and high sensitivity cardiac troponin T (hscTNT) concentrations. RESULTS S100β and myoglobin concentrations were elevated following both apnoeic interventions (p < 0.001; p ≤ 0.028, respectively) but not after CTL (p ≥ 0.348). S100β increased from baseline (0.024 ± 0.005 µg/L) at 30 (STA, +149%, p < 0.001; DYN, +166%, p < 0.001) and 90 min (STA, +129%, p < 0.001; DYN, +132%, p = 0.008) following the last apnoeic repetition. Myoglobin was higher than baseline (22.3 ± 2.7 ng/ml) at 30 (+42%, p = 0.04), 90 (+64%, p < 0.001) and 180 min (+49%, p = 0.013) post-STA and at 90 min (+63%, p = 0.016) post-DYN. Post-apnoeic S100β and myoglobin concentrations were higher than CTL (STA, p < 0.001; DYN, p ≤ 0.004). NSE and hscTNT did not change from basal concentrations after the apnoeic (p ≥ 0.146) nor following the eupnoeic (p ≥ 0.553) intervention. CONCLUSIONS This study suggests that a series of repeated maximal static and dynamic apnoeas transiently disrupt the blood-brain barrier and instigate muscle injury but do not induce neuronal-parenchymal damage or myocardial damage.
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Affiliation(s)
- Antonis Elia
- Division of Environmental Physiology, School of Chemistry, Bioengineering and Health, KTH Royal Institute of Technology, Stockholm, Sweden.,Carnegie School of Sport, Leeds Beckett University, Leeds, UK
| | - David R Woods
- Carnegie School of Sport, Leeds Beckett University, Leeds, UK.,Research and Clinical Innovation, Royal Centre for Defence Medicine, Birmingham, UK
| | | | - Matthew J Lees
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, Ontario, Canada
| | - John P O'Hara
- Carnegie School of Sport, Leeds Beckett University, Leeds, UK
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11
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Solich-Talanda M, Żebrowska A, Mikołajczyk R, Kostorz-Nosal S, Ziora D, Jastrzębski D, Siermontowski P. Effect of Apnea-Induced Hypoxia on Cardiovascular Adaptation and Circulating Biomarkers of Oxidative Stress in Elite Breath-Hold Divers. Front Physiol 2021; 12:726434. [PMID: 34566688 PMCID: PMC8458773 DOI: 10.3389/fphys.2021.726434] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 08/09/2021] [Indexed: 11/13/2022] Open
Abstract
Given the previous evidence that breath-hold diving is a cause of physiological stress, this study aimed to determine whether a combination static and dynamic apnea would affect total oxidant status, nitric oxide, heat shock proteins and cardiovascular parameters in elite freedivers. Thirteen finalists of the World and European championships in swimming pool breath-hold diving participated in the study. Whole-body plethysmography and electrocardiography was performed to determine the cardiorespiratory variables at baseline and during the simulation static apnea. An assessment of the heart rate, blood oxygen saturation and biochemical variables was performed before and in response to a combination of a static followed by a dynamic apnea. Static and dynamic breath-holding had a significant effect on oxidative stress, as evidenced by an increase in the total oxidant status/capacity (p < 0.001). The post apnea concentrations of heat shock proteins 27 (HSP27) were significantly elevated (p < 0.03, but total antioxidant status (TAS), HSP90, HSP70, and nitric oxide (NO) changes were not significant. levels under the influence of the static and dynamic breath-hold protocol. A significant positive correlation between HSPs and TAS (r = 0.63; p < 0.05) as well as NO levels was associated with beneficial cardiovascular adaptation. An increase in serum HSP27 levels mediated in nitric oxide levels could explain its important role in improving cardiovascular functions in elite freedivers. Further studies are necessary to explain the exact mechanisms of breath holds training of cardiovascular adaptation responsible for maintaining adequate oxygen supply in elite divers.
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Affiliation(s)
- Magdalena Solich-Talanda
- Department of Physiological and Medical Sciences, Academy of Physical Education, Katowice, Poland
| | | | - Rafał Mikołajczyk
- Department of Physiological and Medical Sciences, Academy of Physical Education, Katowice, Poland
| | - Sabina Kostorz-Nosal
- Department of Lung Diseases and Tuberculosis, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, Zabrze, Poland
| | - Dariusz Ziora
- Department of Lung Diseases and Tuberculosis, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, Zabrze, Poland
| | - Dariusz Jastrzębski
- Department of Lung Diseases and Tuberculosis, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, Zabrze, Poland
| | - Piotr Siermontowski
- Department of Underwater Works Technology, Polish Naval Academy, Gdynia, Poland
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Evaluation of Physiological Stress Experienced by Divers Maintaining an Upright Position on the Water Surface Depending on the Buoyancy Control Device. POLISH HYPERBARIC RESEARCH 2021. [DOI: 10.2478/phr-2021-0015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Abstract
The knowledge of physiological reactions enabling a diver increasing the functional reserve in a life-threatening situation is not yet complete. It is suggested that the ability to adapt to prolonged stress experienced by divers maintaining an upright position on the water surface is associated with the diver’s individual characteristics and the type of the buoyancy control device. The purpose of this study was to perform a preliminary evaluation of physiological variables in divers wearing two different types of buoyancy control device and floating upright at the surface to determine the level of safety offered by each of them. The physiological variables were measured while participants wearing a classical dive vest and a wing dive vest. The oxygen uptake and heart rate measured after 30 minutes of experiment were significantly greater in participants using wing dive vest than classical dive vest. The results confirm the possibility of using physiological indicators to compare the fatigue and rescue function in divers depending on the buoyancy control device type.
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Serum Cardiac and Skeletal Muscle Marker Changes in Repetitive Breath-hold Diving. SPORTS MEDICINE-OPEN 2021; 7:58. [PMID: 34417928 PMCID: PMC8380208 DOI: 10.1186/s40798-021-00349-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 07/28/2021] [Indexed: 11/10/2022]
Abstract
Background Breath-hold diving (BH-diving) is associated to extreme environmental conditions, prolonged physical activity, and complex adaptation mechanisms to supply enough O2 to vital organs. Consequently, one of the biggest effects could be an increased exercise-induced muscle fatigue, in both skeletal and cardiac muscles that can induce an increase of muscles injury markers including creatine kinase (CK), aspartate transferase (AST), and alanine transferase (ALT) when concerning the skeletal muscle, cardiac creatine kinase isoenzyme (CK-MBm) and cardiac troponin I (cTnI) when concerning the cardiac muscle, and lactate dehydrogenase (LDH) as index of muscle stress. The aim of this study is to investigate serum cardiac and skeletal muscle markers before and after a BH-diving training session. Results We found statistically significant increases of CK (T0: 136.1% p < 0.0001; T1: 138.5%, p < 0.0001), CK-MBm (T0: 145.1%, p < 0.0001; T1: 153.2%, p < 0.0001) LDH (T0: 110.4%, p < 0.0003; T1: 110.1%, p < 0.0013) in both T0 and T1 blood samples, as compared to basal value. AST showed a statistically significant increase only at T0 (106.8%, p < 0.0007) while ALT did not exhibit statistically significant changes. We did not find any changes in cTnI levels between pre-dive and post-dive samples. Conclusions Our data seem to indicate that during a BH-diving training session, skeletal and cardiac muscles react to physical effort releasing stress-related substances. Although the peculiar nature of BH-diving makes it difficult to understand if our results are related only to exercise induced muscle adaptation or whether acute hypoxia or a response to environmental changes (pressure) play a role to explain the observed changes, further studies are needed to better understand if these biomarker changes are linked to physical exercise or to acute hypoxia, or if both conditions play a role. Supplementary Information The online version contains supplementary material available at 10.1186/s40798-021-00349-z.
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Patrician A, Dujić Ž, Spajić B, Drviš I, Ainslie PN. Breath-Hold Diving - The Physiology of Diving Deep and Returning. Front Physiol 2021; 12:639377. [PMID: 34093221 PMCID: PMC8176094 DOI: 10.3389/fphys.2021.639377] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 04/07/2021] [Indexed: 11/13/2022] Open
Abstract
Breath-hold diving involves highly integrative physiology and extreme responses to both exercise and asphyxia during progressive elevations in hydrostatic pressure. With astonishing depth records exceeding 100 m, and up to 214 m on a single breath, the human capacity for deep breath-hold diving continues to refute expectations. The physiological challenges and responses occurring during a deep dive highlight the coordinated interplay of oxygen conservation, exercise economy, and hyperbaric management. In this review, the physiology of deep diving is portrayed as it occurs across the phases of a dive: the first 20 m; passive descent; maximal depth; ascent; last 10 m, and surfacing. The acute risks of diving (i.e., pulmonary barotrauma, nitrogen narcosis, and decompression sickness) and the potential long-term medical consequences to breath-hold diving are summarized, and an emphasis on future areas of research of this unique field of physiological adaptation are provided.
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Affiliation(s)
- Alexander Patrician
- Center for Heart, Lung & Vascular Health, University of British Columbia Okanagan, Kelowna, BC, Canada
| | - Željko Dujić
- Department of Integrative Physiology, University of Split School of Medicine, Split, Croatia
| | - Boris Spajić
- Faculty of Kinesiology, University of Zagreb, Zagreb, Croatia
| | - Ivan Drviš
- Faculty of Kinesiology, University of Zagreb, Zagreb, Croatia
| | - Philip N Ainslie
- Center for Heart, Lung & Vascular Health, University of British Columbia Okanagan, Kelowna, BC, Canada
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Physiology, pathophysiology and (mal)adaptations to chronic apnoeic training: a state-of-the-art review. Eur J Appl Physiol 2021; 121:1543-1566. [PMID: 33791844 PMCID: PMC8144079 DOI: 10.1007/s00421-021-04664-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 03/04/2021] [Indexed: 02/08/2023]
Abstract
Breath-hold diving is an activity that humans have engaged in since antiquity to forage for resources, provide sustenance and to support military campaigns. In modern times, breath-hold diving continues to gain popularity and recognition as both a competitive and recreational sport. The continued progression of world records is somewhat remarkable, particularly given the extreme hypoxaemic and hypercapnic conditions, and hydrostatic pressures these athletes endure. However, there is abundant literature to suggest a large inter-individual variation in the apnoeic capabilities that is thus far not fully understood. In this review, we explore developments in apnoea physiology and delineate the traits and mechanisms that potentially underpin this variation. In addition, we sought to highlight the physiological (mal)adaptations associated with consistent breath-hold training. Breath-hold divers (BHDs) are evidenced to exhibit a more pronounced diving-response than non-divers, while elite BHDs (EBHDs) also display beneficial adaptations in both blood and skeletal muscle. Importantly, these physiological characteristics are documented to be primarily influenced by training-induced stimuli. BHDs are exposed to unique physiological and environmental stressors, and as such possess an ability to withstand acute cerebrovascular and neuronal strains. Whether these characteristics are also a result of training-induced adaptations or genetic predisposition is less certain. Although the long-term effects of regular breath-hold diving activity are yet to be holistically established, preliminary evidence has posed considerations for cognitive, neurological, renal and bone health in BHDs. These areas should be explored further in longitudinal studies to more confidently ascertain the long-term health implications of extreme breath-holding activity.
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Pathophysiological Responses to a Record-Breaking Multi-hour Underwater Endurance Performance: A Case Study. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1289:79-88. [PMID: 32488605 DOI: 10.1007/5584_2020_546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The "Endless Diving Project-Step 36" took place in the harbor waters of the town of Maratea in Italy in September 2014. The goal of the project was an attempt by an experienced male diver, equipped with a wet 7-mm suit and a normal gas tank, to set the world record-breaking of nonstop underwater performance. We studied inflammatory, hematological, and endocrine responses during the extreme condition of the attempt. Venous blood samples were collected at baseline, the day before the attempt; immediately after the return from underwater; then at Day 1, Day 4, and Day 12; and later at Month 1 and Month 41 of follow-up. We found that there was an increase in the content of blood neutrophils, monocytes, and eosinophils and a decrease in lymphocytes at Day 1 and a late increase in basophils at Day 12 after the dive. Inflammatory markers and hematocrit and hemoglobin increased immediately after the dive, dropped at Day 1, and reverted gradually to the control level from Day 4 to Day 12. Serotonin and dopamine decreased, while adrenaline increased at Day 1, gradually recovering in the days of follow-up. Insulin, luteinizing hormone, growth hormone, and prolactin increased, while testosterone, cortisol, 17β-estradiol, thyroid-stimulating hormone, and adrenocorticotropic hormone decreased at Day 1, with a partial recovery at Day 4. We conclude that the homeostatic response to the extreme, prolonged underwater performance showed signs of psychological and pro-inflammatory stress. The hormonal response reflected an acute testicular insufficiency. These responses resembled those characteristics for ultra-endurance exercise accompanied by vasculitis and dehydration.
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Maternal Serum VEGF Predicts Abnormally Invasive Placenta Better than NT-proBNP: a Multicenter Case-Control Study. Reprod Sci 2020; 28:361-370. [PMID: 33025531 PMCID: PMC7808970 DOI: 10.1007/s43032-020-00319-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 09/14/2020] [Indexed: 11/24/2022]
Abstract
The aim of this study was to test if maternal serum vascular endothelial growth factor (VEGF) or N-terminal pro B-type natriuretic peptide (NT-proBNP) predicts abnormally invasive placenta (AIP) better. Secondary objective was to test whether the serum levels of VEGF and NT-proBNP can predict the degree of invasion. In a multicenter case–control study design, gestational age-matched serum samples from pregnant women with AIP (n = 44) and uncomplicated pregnancies (n = 55) who had been enrolled at Charité – Universitätsmedizin Berlin, Germany and Centre Hospitalier Régional de la Citadelle in Liège, Belgium were analyzed. Maternal blood serum VEGF and NT-proBNP levels were immunoassayed from samples taken immediately before delivery (GA median: 35 weeks). Biomarker levels were compared between AIP and control group. The correlation of biomarker levels with the clinical AIP degree was assessed. The predictive biomarker ability was characterized through a multivariate regression model and receiver operating characteristic curves. Women with AIP had significantly lower maternal serum VEGF levels (AIP mean 285 pg/ml, 95% CI 248–322, vs. control: 391 pg/ml, 95% CI 356–426, p < 0.01) and higher NT-proBNP levels (AIP median 329 pg/ml, IQR 287–385, vs. control 295 pg/ml, IQR 273–356, p = 0.03). Maternal serum VEGF levels were able to predict AIP better (AUC = 0.729, 0.622–0.836, p < 0.001; VEGF + number of previous cesarean deliveries: AUC = 0.915, 0.853–0.977, p < 0.001). Maternal serum VEGF levels correlated inversely with the clinical AIP degree (r = − 0.32, p < 0.01). In short, maternal serum VEGF, more than NT-proBNP, can help in predicting AIP and hints at the degree of invasion.
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Hematologic changes after short term hypoxia in non-elite apnea divers under voluntary dry apnea conditions. PLoS One 2020; 15:e0237673. [PMID: 32790747 PMCID: PMC7425904 DOI: 10.1371/journal.pone.0237673] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 07/30/2020] [Indexed: 12/30/2022] Open
Abstract
Purpose This study investigated the acute changes in full spectrum differential blood cell count including reticulocytes and immature reticulocytes after a voluntary maximal dry apnea in non-elite divers. Aim of the present study is to obtain information on important regulatory compensation mechanisms and to provide insights into apneic regulatory processes. Methods Ten apnea divers performed a voluntary dry mean apnea time of 317 sec [SD ±111 sec]. Differential blood cell count including reticulocytes was measured before and immediately after a single maximal breath-hold. To evaluate kinetics, blood samples were also taken after 30 min and 4 h. Value distributions are presented with dot plots. P-values were calculated using a mixed linear model for time dependency. Four difference values were compared to baseline values with Dunnett’s procedure. Results Significant changes were found in red blood cell parameters for erythrocytes, red cell distribution width, hematocrit, hemoglobin, MCV, reticulocytes and immature reticulocytes, and in white blood cell parameters for leucocytes, lymphocytes, immature granulocytes, monocytes, basophile granulocytes, neutrophil granulocytes and eosinophil granulocytes and for thrombocytes. Conclusion Adaptive mechanisms regarding cell counts in elite apnea divers are not readily transferable to non-elite recreational sportspersons. Divers and physicians should be aware of the limited adaptive performance of humans in the case of extended apnea.
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Tissue damage in the heart after cardiac arrest induced by asphyxia and hemorrhage in newborn pigs. Pediatr Res 2019; 86:709-718. [PMID: 31336381 DOI: 10.1038/s41390-019-0505-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 07/03/2019] [Accepted: 07/09/2019] [Indexed: 12/21/2022]
Abstract
BACKGROUND Asphyxia of newborns is a severe and frequent challenge of the peri- and postnatal period. METHODS Forty-four neonatal piglets underwent asphyxia and hemorrhage (AH), followed by resuscitation with blood or crystalloid transfusion. In this study, 15 piglets (blood n = 9, NaCl n = 6, mean age 31 h) were randomly chosen. Four hours after return of spontaneous circulation, heart tissue and blood were collected. Analyses of heart fatty acid binding protein (HFABP), cardiac troponin I (TnI) levels, and activation of the complement system were performed. Histological staining for connexin 43 (Cx43) and complement C5a receptor 1 (C5aR1) was performed. RESULTS Following AH, systemic elevation of cardiac TnI and HFABP revealed cardiac damage in both groups. Systemic activation of the complement system and the appearance of extracellular histones in plasma of the blood transfusion group were observed. The Cx43 was translocated from the intercalated discs to the cytosol after AH. Cardiac glycogen concentration was reduced in both groups. A significant reduction of C5aR1 in the left ventricle and a significant elevation of the heart injury score were investigated after blood transfusion. CONCLUSION AH leads to alteration of the heart, particularly in Cx43 and glycogen reserves, as well as local inflammation.
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