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Sammito S, Thielmann B, Klussmann A, Deußen A, Braumann KM, Böckelmann I. Guideline for the application of heart rate and heart rate variability in occupational medicine and occupational health science. J Occup Med Toxicol 2024; 19:15. [PMID: 38741189 DOI: 10.1186/s12995-024-00414-9] [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: 12/10/2023] [Accepted: 04/24/2024] [Indexed: 05/16/2024] Open
Abstract
This updated guideline replaces the "Guideline for the application of heart rate and heart rate variability in occupational medicine and occupational health science" first published in 2014. Based on the older version of the guideline, the authors have reviewed and evaluated the findings on the use of heart rate (HR) and heart rate variability (HRV) that have been published in the meantime and incorporated them into a new version of this guideline.This guideline was developed for application in clinical practice and research purposes in the fields of occupational medicine and occupational science to complement evaluation procedures with respect to exposure and risk assessment at the workplace by the use of objective physiological workload indicators. In addition, HRV is also suitable for assessing the state of health and for monitoring the progress of illnesses and preventive medical measures. It gives an overview of factors influencing the regulation of the HR and HRV at rest and during work. It further illustrates methods for measuring and analyzing these parameters under standardized laboratory and real workload conditions, areas of application as well as the quality control procedures to be followed during the recording and evaluation of HR and HRV.
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Affiliation(s)
- Stefan Sammito
- Department of Occupational Medicine, Medical Faculty, Otto-von-Guericke University Magdeburg, Magdeburg, Germany.
- German Air Force Centre of Aerospace Medicine, Experimental Aerospace Medicine Research, Flughafenstraße 1, Cologne, 51147, Germany.
| | - Beatrice Thielmann
- Department of Occupational Medicine, Medical Faculty, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - Andre Klussmann
- Competence Centre Health (CCG), Department Health Sciences, University of Applied Sciences (HAW) Hamburg, Hamburg, Germany
| | - Andreas Deußen
- Department of Physiology, Medical Faculty, TU Dresden, Dresden, Germany
| | | | - Irina Böckelmann
- Department of Occupational Medicine, Medical Faculty, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
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Vilca Coaquira KM, Rojas Chambilla RA, Tejada Flores J, Tintaya Ramos HO, Quispe Trujillo MM, Quispe Humpiri SA, Calisaya Huacasi ÁG, Pino Vanegas YM, Peña Vicuña GF, Salazar Granara AA, Tacuna Calderon AL, Garcia Bedoya NM, Yang M, Hancco Zirena I. Lower glycemia levels in subjects with excessive erythrocytosis during the oral glucose tolerance test living in conditions of severe hypoxia. Front Physiol 2024; 15:1387132. [PMID: 38655033 PMCID: PMC11035787 DOI: 10.3389/fphys.2024.1387132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 03/20/2024] [Indexed: 04/26/2024] Open
Abstract
Background Previous studies showed that residents of higher elevations have lower glucose levels. Our objective in this study is to determine the basal and postprandial glucose levels in apparently healthy permanent residents of the miner population center of La Rinconada located 5100 meters (m) above sea level. Method Forty male permanent residents of the Rinconada miner population center were studied. The oral glucose tolerance test was used to evaluate basal and postprandial glycemia levels at 1, 2, and 3 h. Results The individuals had a mean age of 43.95 ± 8.54 years. Basal glycemia in subjects without excessive erythrocytosis (EE) was 73.3 ± 7.9 mg/dL, while levels in patients with EE were 57.98 ± 7.38 mg/dL. In the postprandial period, at 1 h after oral glucose overload, a mean value of 76.35 ± 13.53 mg/dL was observed in subjects with EE compared to 94.68 ± 9.98 mg/dL in subjects without EE. After 2 h, subjects with EE had a glycemia level of 72.91 ± 9.17 mg/dL EE compared to 90.73 ± 13.86 mg/dL without EE. At 3 h, the average glycemia level in subjects with EE was 70.77 ± 8.73 mg/dL compared to 87.79 ± 14.16 mg/dL in those without EE. Conclusion These findings suggest that under hypoxic conditions, glycemia levels are lower in both subjects with and without EE, having obtained lower levels in subjects with EE in relation to those with normal values of Hb and Hct. The results of this study indicate that in the conditions of severe hypoxia, blood glucose levels are below the values considered normal for sea level.
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Affiliation(s)
| | | | - Jeancarlo Tejada Flores
- Facultad de Medicina Humana, Universidad Nacional Del Altiplano, Puno, Perú
- ACEM UNA, Puno, Perú
| | | | | | | | | | - Yony M. Pino Vanegas
- Facultad De Educación, Escuela Profesional De Educación Física, UNA Puno, Puno, Perú
| | | | | | - Ana Lucia Tacuna Calderon
- Instituto De Investigación en Medicina De Altura (CIMA), Facultad De Medicina Humana, Universidad De San Martín De Porres, Lima, Perú
| | | | - Moua Yang
- Division of Hemostasis and Thrombosis, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States
| | - Ivan Hancco Zirena
- Instituto De Investigación en Medicina De Altura (CIMA), Facultad De Medicina Humana, Universidad De San Martín De Porres, Lima, Perú
- Division of Hemostasis and Thrombosis, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States
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Kumar P, Bharti VK, Kumar K. Effect of short-term exposure to high-altitude hypoxic climate on feed-intake, blood glucose level and physiological responses of native and non-native goat. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2024; 68:795-806. [PMID: 38374293 DOI: 10.1007/s00484-024-02624-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 01/03/2024] [Accepted: 01/14/2024] [Indexed: 02/21/2024]
Abstract
The exposure to high altitude and cold stress poses challenges in maintaining normal physiological standards and body homeostasis in non-native animals. To enhance our understanding of the physiology of native and non-native goats in high-altitude environments, we conducted a comparative study to examine the impact of natural hypoxic and cold stress conditions on their feed intake (FIT) and associated changes in physiological responses, including plasma glucose concentration (PGC). The study took place at an altitude of 3505.2 m above mean sea level and involved twenty-two healthy females from two different breeds of goats. This study was conducted over a period of 56 days after the arrival of non-native Black Bengal goats (BBN) and compared with native Changthangi (CHAN) goats. Both groups were extensively reared in a natural high-altitude and cold-stress environment in Leh, India, and were subjected to defined housing and management practices. The parameters evaluated included FIT, PGC, respiration rate, heart rate, pulse rate, and rectal temperature. High altitudes had a significant (p < 0.05) impact on FIT, PGC, respiration rate, heart rate, pulse rate, and rectal temperature in BBN, whereas these parameters remained stable in CHAN throughout the study period. Additionally, the detrimental effects of high-altitude stress were more pronounced in non-native goats compared to native goats. These findings suggest that physiological responses in non-native goats tend to stabilize after an initial period of adverse effects in high-altitude environments. Based on the physiological responses and glucose concentration, it is recommended to pay special attention to the nutrition of non-native goats for up to the third week (21 days) after their arrival in high-altitude areas.
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Affiliation(s)
- Prabhat Kumar
- DRDO-Defence Institute of High-Altitude Research (DIHAR), Leh, Ladakh UT, India.
- Indira Gandhi Institute of Medical Sciences (IGIMS), Patna, Bihar, India.
| | - Vijay K Bharti
- DRDO-Defence Institute of High-Altitude Research (DIHAR), Leh, Ladakh UT, India.
| | - Krishna Kumar
- DRDO-Defence Institute of High-Altitude Research (DIHAR), Leh, Ladakh UT, India
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Su R, Peng P, Zhang W, Huang J, Fan J, Zhang D, He J, Ma H, Li H. Dose-effect of exercise intervention on heart rate variability of acclimatized young male lowlanders at 3,680 m. Front Physiol 2024; 15:1331693. [PMID: 38606008 PMCID: PMC11007668 DOI: 10.3389/fphys.2024.1331693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 03/14/2024] [Indexed: 04/13/2024] Open
Abstract
This study investigated whether exercise could improve the reduced HRV in an environment of high altitude. A total of 97 young, healthy male lowlanders living at 3,680 m for >1 year were recruited. They were randomized into four groups, of which three performed-low-, moderate-, and high-intensity (LI, MI, HI) aerobic exercise for 4 weeks, respectively. The remaining was the control group (CG) receiving no intervention. For HI, compared to other groups, heart rate (p = 0.002) was significantly decreased, while standard deviation of RR intervals (p < 0.001), SD2 of Poincaré plot (p = 0.046) and the number of successive RR interval pairs that differ by > 50 ms divided by total number of RR (p = 0.032), were significantly increased after intervention. For MI, significantly increase of trigonometric interpolation in NN interval (p = 0.016) was observed after exercise. Further, a decrease in systolic blood pressure (SBP) after high-intensity exercise was found significantly associated with an increase in SD2 (r = - 0.428, p = 0.042). These results indicated that there was a dose effect of different intensities of aerobic exercise on the HRV of acclimatized lowlanders. Moderate and high-intensity aerobic exercise would change the status of the autonomic nervous system (ANS) and decrease the blood pressure of acclimatized lowlanders exposed to high altitude.
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Affiliation(s)
- Rui Su
- Key Laboratory of High Altitudes Brain Science and Environmental Acclimation, Tibet University, Lhasa, China
- School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing, China
| | - Ping Peng
- Key Laboratory of High Altitudes Brain Science and Environmental Acclimation, Tibet University, Lhasa, China
| | - Wenrui Zhang
- Key Laboratory of High Altitudes Brain Science and Environmental Acclimation, Tibet University, Lhasa, China
| | - Jie Huang
- Key Laboratory of High Altitudes Brain Science and Environmental Acclimation, Tibet University, Lhasa, China
| | - Jing Fan
- Key Laboratory of High Altitudes Brain Science and Environmental Acclimation, Tibet University, Lhasa, China
| | - Delong Zhang
- Key Laboratory of Brain, Cognition and Education Sciences, Ministry of Education, Guangzhou, China
- School of Psychology, Center for Studies of Psychological Application, and Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou, China
| | - Jiayuan He
- National Clinical Research Center for Geriatric, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Med-X Center for Manufacturing, Sichuan University, Chengdu, Sichuan, China
| | - Hailin Ma
- Key Laboratory of High Altitudes Brain Science and Environmental Acclimation, Tibet University, Lhasa, China
| | - Hao Li
- Key Laboratory of High Altitudes Brain Science and Environmental Acclimation, Tibet University, Lhasa, China
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Álvarez-Millán L, Castillo-Castillo D, Quispe-Siccha R, Pérez-Pacheco A, Angelova M, Rivera-Sánchez J, Fossion R. Frailty Syndrome as a Transition from Compensation to Decompensation: Application to the Biomechanical Regulation of Gait. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:5995. [PMID: 37297599 PMCID: PMC10253052 DOI: 10.3390/ijerph20115995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 03/17/2023] [Accepted: 05/24/2023] [Indexed: 06/12/2023]
Abstract
Most gait parameters decrease with age and are even more importantly reduced with frailty. However, other gait parameters exhibit different or even opposite trends for aging and frailty, and the underlying reason is unclear. Literature focuses either on aging, or on frailty, and a comprehensive understanding of how biomechanical gait regulation evolves with aging and with frailty seems to be lacking. We monitored gait dynamics in young adults (19-29 years, n = 27, 59% women), middle-aged adults (30-59 years, n = 16, 62% women), and non-frail (>60 years, n = 15, 33% women) and frail older adults (>60 years, n = 31, 71% women) during a 160 m walking test using the triaxial accelerometer of the Zephyr Bioharness 3.0 device (Zephyr Technology, Annapolis, MD, USA). Frailty was evaluated using the Frail Scale (FS) and the Clinical Frailty Scale (CFS). We found that in non-frail older adults, certain gait parameters, such as cadence, were increased, whereas other parameters, such as step length, were decreased, and gait speed is maintained. Conversely, in frail older adults, all gait parameters, including gait speed, were decreased. Our interpretation is that non-frail older adults compensate for a decreased step length with an increased cadence to maintain a functional gait speed, whereas frail older adults decompensate and consequently walk with a characteristic decreased gait speed. We quantified compensation and decompensation on a continuous scale using ratios of the compensated parameter with respect to the corresponding compensating parameter. Compensation and decompensation are general medical concepts that can be applied and quantified for many, if not all, biomechanical and physiological regulatory mechanisms of the human body. This may allow for a new research strategy to quantify both aging and frailty in a systemic and dynamic way.
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Affiliation(s)
- Lesli Álvarez-Millán
- Doctorado en Ciencias Biomédicas, Universidad Nacional Autónoma de México (UNAM), Mexico City 04510, Mexico;
- Centro de Ciencias de la Complejidad (C3), Universidad Nacional Autónoma de México (UNAM), Mexico City 04510, Mexico
| | - Daniel Castillo-Castillo
- Unidad de Investigación y Desarrollo Tecnológico (UIDT), Hospital General de México Dr. Eduardo Liceaga, Mexico City 06720, Mexico; (D.C.-C.); (R.Q.-S.); (A.P.-P.)
| | - Rosa Quispe-Siccha
- Unidad de Investigación y Desarrollo Tecnológico (UIDT), Hospital General de México Dr. Eduardo Liceaga, Mexico City 06720, Mexico; (D.C.-C.); (R.Q.-S.); (A.P.-P.)
| | - Argelia Pérez-Pacheco
- Unidad de Investigación y Desarrollo Tecnológico (UIDT), Hospital General de México Dr. Eduardo Liceaga, Mexico City 06720, Mexico; (D.C.-C.); (R.Q.-S.); (A.P.-P.)
| | - Maia Angelova
- School of Information Technology, Melbourne Burwood Campus, Deakin University, Burwood, VIC 3125, Australia;
| | - Jesús Rivera-Sánchez
- Servicio de Geriatría, Hospital General de México Dr. Eduardo Liceaga, Mexico City 06720, Mexico;
| | - Ruben Fossion
- Centro de Ciencias de la Complejidad (C3), Universidad Nacional Autónoma de México (UNAM), Mexico City 04510, Mexico
- Instituto de Ciencias Nucleares (ICN), Universidad Nacional Autónoma de México (UNAM), Mexico City 04510, Mexico
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Pruter WW, Klassen SA, Dominelli PB, Wiggins CC, Senefeld JW, Roy TK, Joyner MJ, Baker SE. Attenuated cardiac autonomic function in humans with high-affinity hemoglobin and compensatory polycythemia. Am J Physiol Regul Integr Comp Physiol 2023; 324:R625-R634. [PMID: 36878486 PMCID: PMC10085552 DOI: 10.1152/ajpregu.00113.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 02/28/2023] [Accepted: 03/01/2023] [Indexed: 03/08/2023]
Abstract
During hypoxic exposure, humans with high-affinity hemoglobin (and compensatory polycythemia) have blunted increases in heart rate compared with healthy humans with typical oxyhemoglobin dissociation curves. This response may be associated with altered autonomic control of heart rate. Our hypothesis-generating study aimed to investigate cardiac baroreflex sensitivity and heart rate variability among nine humans with high-affinity hemoglobin [6 females, O2 partial pressure at 50% [Formula: see text] (P50) = 16 ± 1 mmHg] compared with 12 humans with typical affinity hemoglobin (6 F, P50 = 26 ± 1 mmHg). Participants breathed normal room air for a 10-min baseline, followed by 20 min of isocapnic hypoxic exposure, designed to lower the arterial partial pressure O2 ([Formula: see text]) to ∼50 mmHg. Beat-by-beat heart rate and arterial blood pressure were recorded. Data were averaged in 5-min periods throughout the hypoxia exposure, beginning with the last 5 min of baseline in normoxia. Spontaneous cardiac baroreflex sensitivity and heart rate variability were determined using the sequence method and the time and frequency domain analyses, respectively. Cardiac baroreflex sensitivity was lower in humans with high-affinity hemoglobin than controls at baseline and during isocapnic hypoxic exposure (normoxia: 7 ± 4 vs. 16 ± 10 ms/mmHg, hypoxia minutes 15-20: 4 ± 3 vs. 14 ± 11 ms/mmHg; group effect: P = 0.02, high-affinity hemoglobin vs. control, respectively). Heart rate variability calculated in both the time (standard deviation of the N-N interval) and frequency (low frequency) domains was lower in humans with high-affinity hemoglobin than in controls (all P < 0.05). Our data suggest that humans with high-affinity hemoglobin may have attenuated cardiac autonomic function.
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Affiliation(s)
- Wyatt W Pruter
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States
| | - Stephen A Klassen
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States
- Department of Kinesiology, Brock University, St. Catharines, Ontario, Canada
| | - Paolo B Dominelli
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - Chad C Wiggins
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States
| | - Jonathon W Senefeld
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States
| | - Tuhin K Roy
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States
| | - Michael J Joyner
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States
| | - Sarah E Baker
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States
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Tartibian B, Azadpour N, Eslami R, Khayat SMA. Home-based exercise alters pulmonary function and cellular stress markers in overweight middle-aged men during covid-19 Home quarantine. BMC Sports Sci Med Rehabil 2023; 15:61. [PMID: 37081518 PMCID: PMC10116448 DOI: 10.1186/s13102-023-00673-9] [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: 10/23/2022] [Accepted: 04/13/2023] [Indexed: 04/22/2023]
Abstract
BACKGROUND This study aimed to investigate the effects of a combined home-based exercise program on potential indicators of severe coronavirus disease 2019 (COVID-19) in overweight middle-aged men during home quarantine caused by COVID-19. METHODS Forty men (aged 45-64 years) were assigned to the exercise (EXE, n = 20) or control (CON, n = 20) groups. A 6-week combined program was carried out three days/week, starting at 20 min per session at 50% maximal heart rate (HRmax) and advancing to 45 min at 70% HRmax. Pulmonary functional and cellular stress biomarkers were measured before and after the training program. Analysis of the covariance (ANCOVA) was used for comparison between the two groups considering the baseline values. RESULTS Thirty-six participants (EXE, n = 17; CON, n = 19) completed the research protocol. The EXE group showed post-training improvements in forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC, Vital capacity (VC), and Forced expiratory flow at 25-75% (FEF25-75) compared to the CON group (P < 0. 05). Further, the plasma levels of fibrinogen, Interleukin (IL)-6, Interleukin (IL)-1β, D-dimer, and angiotensin (Ang II) decreased in the EXE group compared to the CON group (P < 0. 05). After six weeks of the training program, leukocyte counts increased in the EXE group compared to the CON group (P < 0. 05). There was a significant positive correlation between body mass index (BMI) with cardiovascular and inflammatory biomarkers other than white blood cells (WBC) in the EXE group (P < 0.05). CONCLUSIONS The findings suggest that combined home-based exercise during home quarantine improves risk factors for severe COVID-19 in overweight middle-aged men. These improvements were further correlated with changes in BMI. Future research is required to confirm the findings of this study.
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Affiliation(s)
- Bakhtyar Tartibian
- Department of Exercise Physiology, Faculty of Physical Education and Sport Sciences, Allameh Tabataba'i University, Tehran, Iran.
| | - Noushin Azadpour
- Department of Physiotherapy, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Rasoul Eslami
- Department of Exercise Physiology, Faculty of Physical Education and Sport Sciences, Allameh Tabataba'i University, Tehran, Iran
| | - Sirwan Mohammad Amini Khayat
- Department of Exercise Physiology, Faculty of Physical Education and Sport Sciences, Urmia University, Urmia, Iran
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Hou J, Wen X, Long P, Xiong S, Liu H, Cai L, Deng H, Zhang Z. The role of post-translational modifications in driving abnormal cardiovascular complications at high altitude. Front Cardiovasc Med 2022; 9:886300. [PMID: 36186970 PMCID: PMC9515308 DOI: 10.3389/fcvm.2022.886300] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 06/16/2022] [Indexed: 11/13/2022] Open
Abstract
The high-altitude environment is characterized by hypobaric hypoxia, low temperatures, low humidity, and high radiation, which is a natural challenge for lowland residents entering. Previous studies have confirmed the acute and chronic effects of high altitude on the cardiovascular systems of lowlanders. Abnormal cardiovascular complications, including pulmonary edema, cardiac hypertrophy and pulmonary arterial hypertension were commonly explored. Effective evaluation of cardiovascular adaptive response in high altitude can provide a basis for early warning, prevention, diagnosis, and treatment of altitude diseases. At present, post-translational modifications (PTMs) of proteins are a key step to regulate their biological functions and dynamic interactions with other molecules. This process is regulated by countless enzymes called “writer, reader, and eraser,” and the performance is precisely controlled. Mutations and abnormal expression of these enzymes or their substrates have been implicated in the pathogenesis of cardiovascular diseases associated with high altitude. Although PTMs play an important regulatory role in key processes such as oxidative stress, apoptosis, proliferation, and hypoxia response, little attention has been paid to abnormal cardiovascular response at high altitude. Here, we reviewed the roles of PTMs in driving abnormal cardiovascular complications at high altitude.
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Affiliation(s)
- Jun Hou
- Department of Cardiology, Chengdu Third People’s Hospital, Cardiovascular Disease Research Institute of Chengdu, Affiliated Hospital of Southwest Jiaotong University, Chengdu, China
- School of Material Science and Engineering, Southwest Jiaotong University, Chengdu, China
| | - Xudong Wen
- Department of Gastroenterology and Hepatology, Chengdu First People’s Hospital, Chengdu, China
| | - Pan Long
- School of Material Science and Engineering, Southwest Jiaotong University, Chengdu, China
| | - Shiqiang Xiong
- Department of Cardiology, Chengdu Third People’s Hospital, Cardiovascular Disease Research Institute of Chengdu, Affiliated Hospital of Southwest Jiaotong University, Chengdu, China
| | - Hanxiong Liu
- Department of Cardiology, Chengdu Third People’s Hospital, Cardiovascular Disease Research Institute of Chengdu, Affiliated Hospital of Southwest Jiaotong University, Chengdu, China
| | - Lin Cai
- Department of Cardiology, Chengdu Third People’s Hospital, Cardiovascular Disease Research Institute of Chengdu, Affiliated Hospital of Southwest Jiaotong University, Chengdu, China
- *Correspondence: Lin Cai,
| | - Haoyu Deng
- Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
- Center for Heart and Lung Innovation, St. Paul’s Hospital, University of British Columbia, Vancouver, BC, Canada
- Department of Vascular Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Haoyu Deng,
| | - Zhen Zhang
- Department of Cardiology, Chengdu Third People’s Hospital, Cardiovascular Disease Research Institute of Chengdu, Affiliated Hospital of Southwest Jiaotong University, Chengdu, China
- Zhen Zhang,
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Hou J, Zheng D, Wen X, Xiao W, Han F, Lang H, Xiong S, Jiang W, Hu Y, He M, Long P. Proteomic and Morphological Profiling of Mice Ocular Tissue During High-altitude Acclimatization Process: An Animal Study at Lhasa. J Inflamm Res 2022; 15:2835-2853. [PMID: 35645575 PMCID: PMC9135145 DOI: 10.2147/jir.s361174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 04/27/2022] [Indexed: 12/31/2022] Open
Abstract
Purpose High-altitude environment mainly with hypobaric hypoxia could induce pathological alterations in ocular tissue. Previous studies have mostly focused on sporadic case reports and simulated high-altitude hypoxia experiments. This aim of this study was to explore the proteomic and morphological changes of ocular tissue in mice at real altitude environment. Methods In this study, mice were flown from Chengdu (elevation: 500 m) to Lhasa (elevation: 3600 m). After exposure for 1day, 3, 6, 10, 20, 30, and 40days, the mice were euthanatized to obtain blood and ocular tissue. Serological tests, ocular pathological examinations, integral ocular proteomics analysis, and Western blot were conducted. Results We focused on acute phase (1–3 days) and chronic phase (>30 days) during high-altitude acclimatization. Serum interleukin-1 was increased at 3 days, while superoxide dismutase, interleukin-6, and tumor necrosis factor-α showed no statistical changes. H&E staining demonstrated that the cornea was edematous at 3 days and exhibited slower proliferation at 30 days. The choroid showed a consistently significant thickening, while there existed no noticeable changes in retinal thickness. Overall, 4073 proteins were identified, among which 71 and 119 proteins were detected to have significant difference at 3 days and 40 days when compared with the control group. Functional enrichment analysis found the differentiated proteins at 3 days exposure functionally related with response to radiation, dephosphorylation, negative regulation of cell adhesion, and erythrocyte homeostasis. Moreover, the differential profiles of the proteins at 40 days exposure exhibited changes of regulation of complement activation, regulation of protein activation cascade, regulation of humoral immune response, second-messenger-mediated signaling, regulation of leukocyte activation, and cellular iron homeostasis. Interestingly, we found the ocular proteins with lactylation modification were increased along high-altitude adaptation. Conclusion This is the first work reporting the ocular proteomic and morphological changes at real high-altitude environment. We expect it would deep the understanding of ocular response during altitude acclimatization.
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Affiliation(s)
- Jun Hou
- Department of Cardiology, Chengdu Third People’s Hospital/Affiliated Hospital of Southwest Jiaotong University, Chengdu, People’s Republic of China
| | - Dezhi Zheng
- Department of Cardiovascular Surgery, the 960th Hospital of the PLA Joint Logistic Support Force, Jinan, People’s Republic of China
| | - Xudong Wen
- Department of Gastroenterology and Hepatology, Chengdu First People’s Hospital, Chengdu, People’s Republic of China
| | - Wenjing Xiao
- School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, People’s Republic of China
| | - Fei Han
- Department of Ophthalmology, the General Hospital of Western Theater Command, Chengdu, People’s Republic of China
| | - Hongmei Lang
- The Center of Obesity and Metabolic Diseases, Department of General Surgery, Chengdu Third People’s Hospital & the Affiliated Hospital of Southwest Jiaotong University, Chengdu, People’s Republic of China
| | - Shiqiang Xiong
- Department of Cardiology, Chengdu Third People’s Hospital/Affiliated Hospital of Southwest Jiaotong University, Chengdu, People’s Republic of China
| | - Wei Jiang
- Department of Ophthalmology, the General Hospital of Western Theater Command, Chengdu, People’s Republic of China
| | - Yonghe Hu
- School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, People’s Republic of China
- Yonghe Hu, School of Materials Science and Engineering, Southwest Jiaotong University, No. 111, North First Section of the Second Ring Road, Chengdu, People’s Republic of China, Tel +86-138-8059-6789, Email
| | - Mengshan He
- Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi’an, People’s Republic of China
| | - Pan Long
- School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, People’s Republic of China
- Department of Ophthalmology, the General Hospital of Western Theater Command, Chengdu, People’s Republic of China
- Correspondence: Pan Long, Department of Ophthalmology, the General Hospital of Western Theater Command, Rongdu Avenue #270, Chengdu, People’s Republic of China, Tel +86-181-9125-6132, Email
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10
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Muñoz S, Nazzal C, Jimenez D, Frenz P, Flores P, Alcantara-Zapata D, Marchetti N. Health Effects of Chronic Intermittent Hypoxia at a High Altitude among Chilean Miners: Rationale, Design, and Baseline Results of a Longitudinal Study. Ann Work Expo Health 2021; 65:908-918. [PMID: 34435202 DOI: 10.1093/annweh/wxab029] [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: 12/02/2020] [Revised: 03/09/2021] [Accepted: 03/31/2021] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES This study aims to assess the health effects on mining workers of exposure to chronic intermittent hypoxia (CIH) at high- and very high-altitude mining compared with similar work at lower altitudes in Chile, and it also aims to constitute the baseline of a 5-year follow-up study. METHODS We designed a cross-sectional study to assess health conditions in 483 miners working at 2 levels of altitude exposure: 336 working at a very high or high altitude (HA; 247 above 3900-4400 m, and 89 at 3000-3900 m), and 147 below 2400 m. Subjects were randomly selected in two stages. First, a selection of mines from a census of mines in each altitude stratum was made. Secondly, workers with less than 2 years of employment at each of the selected mines were recruited. The main outcomes measured at the baseline were mountain sickness, sleep alterations, hypertension, body mass index, and neurocognitive functions. RESULTS Prevalence of acute mountain sickness (AMS) was 28.4% in the very high-altitude stratum (P = 0.0001 compared with the low stratum), and 71.7% experienced sleep disturbance (P = 0.02). The adjusted odds ratio for AMS was 9.2 (95% confidence interval: 5.2-16.3) when compared with the very high- and low-altitude groups. Motor processing speed and spatial working memory score were lower for the high-altitude group. Hypertension was lower in the highest-altitude subjects, which may be attributed to preoccupational screening even though this was not statistically significant. CONCLUSIONS Despite longer periods of acclimatization to CIH, subjects continue to present AMS and sleep disturbance. Compromise of executive functions was detected, including working memory at HA. Further rigorous research is warranted to understand long-term health impacts of high-altitude mining, and to provide evidence-based policy recommendations.
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Affiliation(s)
- Sergio Muñoz
- Department of Public Health-CIGES, Faculty of Medicine, Universidad de La Frontera, 01145 Av. Francisco Salazar, Casilla 54-D, Temuco, Chile
| | - Carolina Nazzal
- Program of Occupational Health, School of Public Health, Faculty of Medicine, University of Chile, 939 Av. Independencia, Santiago, Chile
| | - Daniel Jimenez
- Program of Occupational Health, School of Public Health, Faculty of Medicine, University of Chile, 939 Av. Independencia, Santiago, Chile
| | - Patricia Frenz
- Program of Occupational Health, School of Public Health, Faculty of Medicine, University of Chile, 939 Av. Independencia, Santiago, Chile
| | - Patricia Flores
- Faculty of Medicine, Psychiatry Department, Catholic University of Chile, 12351 Camino El Alba, Las Condes, Santiago, Chile.,Servicio de Neurología, Departamento de Medicina, Clínica Alemana-Universidad del Desarrollo, Avenida Vitacura 5951, Región Metropolitana de Santiago, Santiago de Chile, Chile
| | - Diana Alcantara-Zapata
- Program of Occupational Health, School of Public Health, Faculty of Medicine, University of Chile, 939 Av. Independencia, Santiago, Chile
| | - Nella Marchetti
- Program of Occupational Health, School of Public Health, Faculty of Medicine, University of Chile, 939 Av. Independencia, Santiago, Chile
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11
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Lang M, Paéz V, Maj G, Silva-Urra J, Labarca-Valenzuela C, Caravita S, Faini A, Cantuarias J, Perez O, Bilo G, Parati G. Blood Pressure Response in Miners Exposed to Chronic Intermittent Hypoxia in Chile. Front Cardiovasc Med 2021; 8:701961. [PMID: 34458335 PMCID: PMC8387657 DOI: 10.3389/fcvm.2021.701961] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 07/12/2021] [Indexed: 12/17/2022] Open
Abstract
Introduction: Limited information is available on blood pressure (BP) behavior in workers exposed to chronic intermittent hypoxia (CIH), and even less is known regarding effects of CIH on 24-h ambulatory BP in those affected by arterial hypertension at sea level (SL). The aims of this study were to assess clinic and 24-h ambulatory BP at SL and at high altitude (HA; 3,870 m above SL) in workers exposed to CIH, and to compare BP response to HA exposure between normotensive and hypertensive workers. Methods: Nineteen normotensive and 18 pharmacologically treated hypertensive miners acclimatized to CIH were included, whose work was organized according to a “7 days-on−7 days-off” shift pattern between SL and HA. All measurements were performed on the second and seventh day of their HA shift and after the second day of SL sojourn. Results: Compared to SL, 24-h systolic BP (SBP) and diastolic BP (DBP) increased at HA [+14.7 ± 12.6 mmHg (p < 0.001) and +8.7 ± 7.2 mmHg (p < 0.001), respectively], and SBP nocturnal fall decreased consistently (−4.1 ± 9.8%; p < 0.05) in all participants, with hypertensives showing higher nocturnal DBP than normotensives (p < 0.05) despite the current therapy. Also, heart rate (HR) nocturnal fall tended to be reduced at HA. In addition, the 24-h SBP/DBP hypertension threshold of ≥130/80 mmHg was exceeded by 39% of workers at SL and by 89% at HA. Clinic HR, SBP, and DBP were significantly higher on the second day of work at HA compared with SL, the increase being more pronounced for SBP in hypertensives (p < 0.05) and accompanied by, on average, mild altitude sickness in both groups. These symptoms and the values of all cardiovascular variables decreased on the seventh day at HA (p < 0.05) regardless of CIH exposure duration. Conclusion: Long history of work at HA according to scheduled CIH did not prevent the occurrence of acute cardiovascular changes at HA during the first days of exposure. The BP response to HA tended to be more pronounced in hypertensive than in normotensive workers despite being already treated; the BP changes were more evident for 24-h ambulatory BP. Twenty-four-hour ABP monitoring is a useful tool for an appropriate evaluation of BP in CIH workers.
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Affiliation(s)
- Morin Lang
- Department of Rehabilitation Sciences and Human Movement, Faculty of Health Sciences, University of Antofagasta, Antofagasta, Chile
| | - Valeria Paéz
- Department of Rehabilitation Sciences and Human Movement, Faculty of Health Sciences, University of Antofagasta, Antofagasta, Chile
| | - Giacomo Maj
- Department of Medicine and Surgery, University of Milano-Bicocca, Milan, Italy
| | - Juan Silva-Urra
- Biomedical Department, Faculty of Health Sciences, University of Antofagasta, Antofagasta, Chile
| | | | - Sergio Caravita
- Department of Cardiovascular, Neural and Metabolic Sciences, Istituto Auxologico Italiano, Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS), Milan, Italy.,Department of Management, Information and Production Engineering, University of Bergamo, Dalmine, Italy
| | - Andrea Faini
- Department of Cardiovascular, Neural and Metabolic Sciences, Istituto Auxologico Italiano, Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS), Milan, Italy
| | | | - Oscar Perez
- Compañia Minera Doña Inés de Collahuasi, Iquique, Chile
| | - Grzegorz Bilo
- Department of Medicine and Surgery, University of Milano-Bicocca, Milan, Italy.,Department of Cardiovascular, Neural and Metabolic Sciences, Istituto Auxologico Italiano, Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS), Milan, Italy
| | - Gianfranco Parati
- Department of Medicine and Surgery, University of Milano-Bicocca, Milan, Italy.,Department of Cardiovascular, Neural and Metabolic Sciences, Istituto Auxologico Italiano, Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS), Milan, Italy
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12
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Mallet RT, Burtscher J, Richalet JP, Millet GP, Burtscher M. Impact of High Altitude on Cardiovascular Health: Current Perspectives. Vasc Health Risk Manag 2021; 17:317-335. [PMID: 34135590 PMCID: PMC8197622 DOI: 10.2147/vhrm.s294121] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 05/12/2021] [Indexed: 12/12/2022] Open
Abstract
Globally, about 400 million people reside at terrestrial altitudes above 1500 m, and more than 100 million lowlanders visit mountainous areas above 2500 m annually. The interactions between the low barometric pressure and partial pressure of O2, climate, individual genetic, lifestyle and socio-economic factors, as well as adaptation and acclimatization processes at high elevations are extremely complex. It is challenging to decipher the effects of these myriad factors on the cardiovascular health in high altitude residents, and even more so in those ascending to high altitudes with or without preexisting diseases. This review aims to interpret epidemiological observations in high-altitude populations; present and discuss cardiovascular responses to acute and subacute high-altitude exposure in general and more specifically in people with preexisting cardiovascular diseases; the relations between cardiovascular pathologies and neurodegenerative diseases at altitude; the effects of high-altitude exercise; and the putative cardioprotective mechanisms of hypobaric hypoxia.
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Affiliation(s)
- Robert T Mallet
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Johannes Burtscher
- Department of Biomedical Sciences, University of Lausanne, Lausanne, CH-1015, Switzerland
- Institute of Sport Sciences, University of Lausanne, Lausanne, CH-1015, Switzerland
| | - Jean-Paul Richalet
- Laboratoire Hypoxie & Poumon, UMR Inserm U1272, Université Sorbonne Paris Nord 13, Bobigny Cedex, F-93017, France
| | - Gregoire P Millet
- Department of Biomedical Sciences, University of Lausanne, Lausanne, CH-1015, Switzerland
- Institute of Sport Sciences, University of Lausanne, Lausanne, CH-1015, Switzerland
| | - Martin Burtscher
- Department of Sport Science, University of Innsbruck, Innsbruck, A-6020, Austria
- Austrian Society for Alpine and High-Altitude Medicine, Mieming, Austria
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13
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Beltrán AR, Arce-Álvarez A, Ramirez-Campillo R, Vásquez-Muñoz M, von Igel M, Ramírez MA, Del Rio R, Andrade DC. Baroreflex Modulation During Acute High-Altitude Exposure in Rats. Front Physiol 2020; 11:1049. [PMID: 32973562 PMCID: PMC7472463 DOI: 10.3389/fphys.2020.01049] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 07/30/2020] [Indexed: 12/25/2022] Open
Abstract
Baroreflex (BR) control is critically dependent of sympathetic and parasympathetic modulation. It has been documented that during acute hypobaric hypoxia there is a BR control impairment, however, the effect of a natural hypoxic environment on BR function is limited and controversial. Therefore, the aim of this study was to determine the effect of acute High-Altitude exposure on sympathetic/parasympathetic modulation of BR control in normal rats. Male Sprague Dawley rats were randomly allocated into Sea-Level (n = 7) and High-Altitude (n = 5) (3,270 m above sea level) groups. The BR control was studied using phenylephrine (Phe) and sodium nitroprusside (SNP) through sigmoidal analysis. The autonomic control of the heart was estimated using heart rate variability (HRV) analysis in frequency domain. Additionally, to determine the maximum sympathetic and parasympathetic activation of BR, spectral non-stationary method analysis, during Phe (0.05 μg/mL) and SNP administration (0.10 μg/mL) were used. Compared to Sea-Level condition, the High-Altitude group displayed parasympathetic withdrawal (high frequency, 0.6-2.4 Hz) and sympathoexcitation (low frequency, 0.04-0.6 Hz). Regarding to BR modulation, rats showed a significant decrease (p < 0.05) of curvature and parasympathetic bradycardic responses to Phe, without significant differences in sympathetic tachycardic responses to SNP after High-Altitude exposure. In addition, the non-stationary analysis of HRV showed a reduction of parasympathetic activation (Phe) in the High-Altitude group. Our results suggest that acute exposure to High-Altitude produces an autonomic and BR control impairment, characterized by parasympathetic withdrawal after 24 h of high-altitude exposure.
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Affiliation(s)
- Ana Rosa Beltrán
- Departamento de Educación, Facultad de Educación, Universidad de Antofagasta, Antofagasta, Chile
- Laboratorio de Fisiología Celular, Departamento Biomédico, Facultad de Ciencias de la Salud, Universidad de Antofagasta, Antofagasta, Chile
| | - Alexis Arce-Álvarez
- Escuela de Kinesiología, Facultad de Salud, Universidad Católica Silva Henríquez, Santiago, Chile
| | - Rodrigo Ramirez-Campillo
- Laboratory of Human Performance, Quality of Life and Wellness Research Group, Department of Physical Activity Sciences, Universidad de Los Lagos, Osorno, Chile
- Centro de Investigación en Fisiología del Ejercicio, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
| | - Manuel Vásquez-Muñoz
- Centro de Investigación en Fisiología del Ejercicio, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
| | - Magdalena von Igel
- Centro de Investigación en Fisiología del Ejercicio, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
| | - Marco A. Ramírez
- Laboratorio de Fisiología Celular, Departamento Biomédico, Facultad de Ciencias de la Salud, Universidad de Antofagasta, Antofagasta, Chile
| | - Rodrigo Del Rio
- Laboratory of Cardiorespiratory Control, Department of Physiology, Pontificia Universidad Católica de Chile, Santiago, Chile
- Centro de Envejecimiento y Regeneración (CARE), Pontificia Universidad Católica de Chile, Santiago, Chile
- Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas, Chile
| | - David C. Andrade
- Centro de Investigación en Fisiología del Ejercicio, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
- Laboratory of Cardiorespiratory Control, Department of Physiology, Pontificia Universidad Católica de Chile, Santiago, Chile
- Pedagogía en Educación Física, Deportes y Recreación, Universidad Mayor, Santiago, Chile
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14
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Soon S, Svavarsdottir H, Downey C, Jayne DG. Wearable devices for remote vital signs monitoring in the outpatient setting: an overview of the field. ACTA ACUST UNITED AC 2020. [DOI: 10.1136/bmjinnov-2019-000354] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Early detection of physiological deterioration has been shown to improve patient outcomes. Due to recent improvements in technology, comprehensive outpatient vital signs monitoring is now possible. This is the first review to collate information on all wearable devices on the market for outpatient physiological monitoring.A scoping review was undertaken. The monitors reviewed were limited to those that can function in the outpatient setting with minimal restrictions on the patient’s normal lifestyle, while measuring any or all of the vital signs: heart rate, ECG, oxygen saturation, respiration rate, blood pressure and temperature.A total of 270 papers were included in the review. Thirty wearable monitors were examined: 6 patches, 3 clothing-based monitors, 4 chest straps, 2 upper arm bands and 15 wristbands. The monitoring of vital signs in the outpatient setting is a developing field with differing levels of evidence for each monitor. The most common clinical application was heart rate monitoring. Blood pressure and oxygen saturation measurements were the least common applications. There is a need for clinical validation studies in the outpatient setting to prove the potential of many of the monitors identified.Research in this area is in its infancy. Future research should look at aggregating the results of validity and reliability and patient outcome studies for each monitor and between different devices. This would provide a more holistic overview of the potential for the clinical use of each device.
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15
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Barhwal KK, Boppana S, Vashishtha V, Mahapatra SC. Conscious Abstinence from Smokeless Tobacco Evokes Higher Withdrawal Response and Impairs Cognitive Performance Independent of Sympathetic Response. Ann Neurosci 2020; 27:29-39. [PMID: 32982097 PMCID: PMC7499824 DOI: 10.1177/0972753120927515] [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] [Indexed: 11/21/2022] Open
Abstract
INTRODUCTION High consumption of smokeless tobacco in adult Indian population increases the risk of developing oral cancers leading to high morbidity and mortality. Though the influence of abstinence from smoking on cognitive performance has been widely studied, the effect of smokeless tobacco on cognitive performance and its association with withdrawal symptoms is less understood. This study comparatively investigates the effect of short-term conscious abstinence and distraction during abstinence from smokeless tobacco consumption on the craving, withdrawal symptoms, sympathetic response, and cognitive performance in tobacco addicts. METHODS Age, sex, education and socioeconomic status matched control (N = 15) and smokeless tobacco addicts (N = 60) were recruited from residential areas in Bhubaneswar for the study. Following randomization of the addicts, conscious abstinence (N = 30) was induced by informed abstinence from tobacco consumption for 8 hours, while distracted cessation (N = 30) was induced by involving the participants in a cognitively engaging task for 8 hours during uninformed tobacco abstinence. RESULTS The results of the study show higher withdrawal symptoms and reduced cognitive performance in volunteers with conscious abstinence which was positively correlated. The decreased cognitive performance in conscious cessation was independent of tobacco-induced increase in the LF:HF ratio and cotinine concentration in saliva. CONCLUSION While conscious abstinence results in higher withdrawal symptoms, distraction during abstinence lowers these symptoms. Inclusion of distraction sessions during cessation can, therefore, be a new element in tobacco control strategies.
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Affiliation(s)
- Kalpana Kumari Barhwal
- Department of Physiology, All India Institute of Medical Sciences (AIIMS), Bhubaneswar, Odisha, India
| | - Sujwal Boppana
- Department of Physiology, All India Institute of Medical Sciences (AIIMS), Bhubaneswar, Odisha, India
| | | | - Sushil Chandra Mahapatra
- Department of Physiology, All India Institute of Medical Sciences (AIIMS), Bhubaneswar, Odisha, India
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16
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Dhar P, Das SK, Barhwal K, Hota SK, Mishra KP, Singh SB. Trans-Himalayan Phytococktail Confers Protection Against Hypobaric Hypoxia-Induced Hippocampal Neurodegeneration and Memory Impairment in Male Sprague Dawley Rats. High Alt Med Biol 2019; 20:279-292. [PMID: 31550185 DOI: 10.1089/ham.2019.0011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Background: Exposure to hypobaric hypoxia (HH) has been reported to cause neurodegeneration and memory impairment. Hippophae rhamnoides, Prunus armeniaca, and Rhodiola imbricata, the indigenous plants of Indian Trans-Himalaya are widely used in traditional Tibetan and Amchi system of medicine. These are rich sources of diverse bioactive metabolites having prophylactic and therapeutic uses against a wide array of neurodegenerative diseases. The objective of this study was to elucidate the prophylactic and neuroprotective efficacy of formulated phytococktail (PC) against simulated HH-induced neurodegeneration in male Sprague Dawley (SD) rats. Materials and Methods: A PC containing H. rhamnoides fruit pulp, P. armeniaca fruit pulp, and R. imbricata dry root extract (100:50:1) was formulated. The neuroprotective efficacy of PC was evaluated in male SD rats following exposure to 7 day HH at simulated altitude (25,000 ft, 282 mm Hg). Rats were divided into four groups viz., normoxia group (NOR), normoxic group treated with PC (NORPC), 7 day hypoxic group treated with vehicle (7DH), and 7 day hypoxic group treated with PC (7DHPC). Memory impairment and neuromorphological alterations were measured. Targeted protein expression was analyzed by immunoblotting study. Results: PC supplementation significantly reduced the oxidative stress markers during exposure to HH. Spatial memory impairment by HH was significantly ameliorated by PC. HH-induced augmented pyknosis, decreased dendritic arborization, and increased Hoechst-positive neurons in hippocampal CA3 region were significantly ameliorated by PC. Immunoblotting study showed upregulation of BDNF and TrkB expression by PC. PC also prevented the hippocampal neurodegeneration by activating the PI3K/AKT signaling pathway, which leads to GSK-3β inactivation by its phosphorylation and alleviation of hippocampal Caspase3 expression leading to inhibition of apoptotic neuronal cell death. Conclusion: The present study advocates the potential role of PC as an effective neuroprotective supplement in preventing HH-induced neurodegeneration. Activation of the PI3K/Akt pathway through BDNF/TrkB interaction following PC supplementation after exposure to HH inhibits hippocampal neuronal apoptosis and memory impairment.
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Affiliation(s)
- Priyanka Dhar
- Defense Institute of High Altitude Research, Defense Research and Development Organization, Leh-Ladakh, India.,Department of Biotechnology, Techno India University, Salt Lake City, India
| | - Saroj Kumar Das
- Defense Institute of High Altitude Research, Defense Research and Development Organization, Leh-Ladakh, India.,Center for Biotechnology, Siksha 'O' Anusandhan (Deemed to be University), Bhubaneswar, India
| | - Kalpana Barhwal
- Defense Institute of High Altitude Research, Defense Research and Development Organization, Leh-Ladakh, India.,All India Institute of Medical Sciences, Bhubaneswar, India
| | - Sunil Kumar Hota
- Defense Institute of High Altitude Research, Defense Research and Development Organization, Leh-Ladakh, India
| | - Kamla Prasad Mishra
- Defense Institute of Physiology and Allied Sciences, Defense Research and Development Organization, Timarpur, India
| | - Shashi Bala Singh
- Defense Institute of Physiology and Allied Sciences, Defense Research and Development Organization, Timarpur, India.,National Institute of Pharmaceutical Education and Research, Balanagar, India
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17
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Seshadri DR, Li RT, Voos JE, Rowbottom JR, Alfes CM, Zorman CA, Drummond CK. Wearable sensors for monitoring the internal and external workload of the athlete. NPJ Digit Med 2019; 2:71. [PMID: 31372506 PMCID: PMC6662809 DOI: 10.1038/s41746-019-0149-2] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 07/08/2019] [Indexed: 11/29/2022] Open
Abstract
The convergence of semiconductor technology, physiology, and predictive health analytics from wearable devices has advanced its clinical and translational utility for sports. The detection and subsequent application of metrics pertinent to and indicative of the physical performance, physiological status, biochemical composition, and mental alertness of the athlete has been shown to reduce the risk of injuries and improve performance and has enabled the development of athlete-centered protocols and treatment plans by team physicians and trainers. Our discussions in this review include commercially available devices, as well as those described in scientific literature to provide an understanding of wearable sensors for sports medicine. The primary objective of this paper is to provide a comprehensive review of the applications of wearable technology for assessing the biomechanical and physiological parameters of the athlete. A secondary objective of this paper is to identify collaborative research opportunities among academic research groups, sports medicine health clinics, and sports team performance programs to further the utility of this technology to assist in the return-to-play for athletes across various sporting domains. A companion paper discusses the use of wearables to monitor the biochemical profile and mental acuity of the athlete.
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Affiliation(s)
- Dhruv R. Seshadri
- Department of Biomedical Engineering, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106 USA
| | - Ryan T. Li
- Department of Orthopaedic Surgery, University Hospitals Cleveland Medical Center, Cleveland, OH 44106 USA
| | - James E. Voos
- University Hospitals Sports Medicine Institute, Cleveland, OH 44106 USA
| | - James R. Rowbottom
- Department of Cardiothoracic Anesthesiology, The Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 USA
| | - Celeste M. Alfes
- Frances Payne Bolton School of Nursing, Case Western Reserve University, 9501 Euclid Avenue, Cleveland, OH 44106 USA
| | - Christian A. Zorman
- Department of Electrical Engineering and Computer Science, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106 USA
| | - Colin K. Drummond
- Department of Biomedical Engineering, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106 USA
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18
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Seshadri DR, Magliato S, Voos JE, Drummond C. Clinical translation of biomedical sensors for sports medicine. J Med Eng Technol 2019; 43:66-81. [PMID: 31119965 DOI: 10.1080/03091902.2019.1612474] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The digital health field has seen a surge in product development over the last decade, with product introductions ranging from wrist monitors, epidermal electronics, electronic pills and smart garments, much of these precipitated through the commercialisation and commoditisation of sensor technology. The emergence of wearable technology has recently garnered heightened interest by physicians and the general public. The convenient use of wireless technology to track and monitor physiological parameters, such as heart rate, distance, sleep and stress, has emerged to become relevant to patient care and human performance assessment. However, collecting data is not enough to inform clinical decision-making. It is essential to translate the acquired data into information relevant to clinicians. Our experiences tell us that team competencies must mirror the interdisciplinary technology itself. Thus, an interdisciplinary team blending expertise from engineering, medicine, and nursing is believed to be essential in translating wearable technology into the field. This review discusses the application of wearable sensors to monitor human performance assessment in domains necessitating accurate, reliable, and timely transmission of acquired bio-metric and bio-vital data. A key result disseminating from our investigations is the need to develop predictive models based off of the data acquired from wearable devices to necessitate the development of athlete-centred treatment plans to expedite the return-to-play time and to maximise performance.
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Affiliation(s)
- Dhruv R Seshadri
- a Department of Biomedical Engineering , Case Western Reserve University , Cleveland , OH , USA
| | - Samantha Magliato
- a Department of Biomedical Engineering , Case Western Reserve University , Cleveland , OH , USA
| | - James E Voos
- b University Hospitals Sports Medicine Institute , Cleveland , OH , USA
| | - Colin Drummond
- a Department of Biomedical Engineering , Case Western Reserve University , Cleveland , OH , USA
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19
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Schwarz EI, Latshang TD, Furian M, Flück D, Segitz S, Müller-Mottet S, Ulrich S, Bloch KE, Kohler M. Blood pressure response to exposure to moderate altitude in patients with COPD. Int J Chron Obstruct Pulmon Dis 2019; 14:659-666. [PMID: 30936690 PMCID: PMC6421900 DOI: 10.2147/copd.s194426] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Purpose Patients with COPD might be particularly susceptible to hypoxia-induced autonomic dysregulation. Decreased baroreflex sensitivity (BRS) and increased blood pressure (BP) variability (BPV) are markers of impaired cardiovascular autonomic regulation and there is evidence for an association between decreased BRS/increased BPV and high cardiovascular risk. The aim of this study was to evaluate the effect of short-term exposure to moderate altitude on BP and measures of cardiovascular autonomic regulation in COPD patients. Materials and methods Continuous morning beat-to-beat BP was noninvasively measured with a Finometer® device for 10 minutes at low altitude (490 m, Zurich, Switzerland) and for 2 days at moderate altitude (2,590 m, Davos Jakobshorn, Switzerland) – the order of altitude exposure was randomized. Outcomes of interest were mean SBP and DBP, BPV expressed as the coefficient of variation (CV), and spontaneous BRS. Changes between low altitude and day 1 and day 2 at moderate altitude were assessed by ANOVA for repeated measurements with Fisher’s exact test analysis. Results Thirty-seven patients with moderate to severe COPD (mean±SD age 64±6 years, FEV1 60%±17%) were included. Morning SBP increased by +10.8 mmHg (95% CI: 4.7–17.0, P=0.001) and morning DBP by +5.0 mmHg (95% CI: 0.8–9.3, P=0.02) in response to altitude exposure. BRS significantly decreased (P=0.03), whereas BPV significantly and progressively increased (P<0.001) upon exposure to altitude. Conclusion Exposure of COPD patients to moderate altitude is associated with a clinically relevant increase in BP, which seems to be related to autonomic dysregulation. Clinical trial registration ClinicalTrials.gov (NCT01875133).
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Affiliation(s)
- Esther I Schwarz
- Department of Pulmonology and Sleep Disorders Centre, University Hospital of Zurich, Zurich, Switzerland,
| | - Tsogyal D Latshang
- Department of Pulmonology and Sleep Disorders Centre, University Hospital of Zurich, Zurich, Switzerland,
| | - Michael Furian
- Department of Pulmonology and Sleep Disorders Centre, University Hospital of Zurich, Zurich, Switzerland,
| | - Deborah Flück
- Department of Pulmonology and Sleep Disorders Centre, University Hospital of Zurich, Zurich, Switzerland,
| | - Sebastian Segitz
- Department of Pulmonology and Sleep Disorders Centre, University Hospital of Zurich, Zurich, Switzerland,
| | - Severine Müller-Mottet
- Department of Pulmonology and Sleep Disorders Centre, University Hospital of Zurich, Zurich, Switzerland,
| | - Silvia Ulrich
- Department of Pulmonology and Sleep Disorders Centre, University Hospital of Zurich, Zurich, Switzerland,
| | - Konrad E Bloch
- Department of Pulmonology and Sleep Disorders Centre, University Hospital of Zurich, Zurich, Switzerland, .,Centre for Integrative Human Physiology, University of Zurich, Zurich, Switzerland,
| | - Malcolm Kohler
- Department of Pulmonology and Sleep Disorders Centre, University Hospital of Zurich, Zurich, Switzerland, .,Centre for Integrative Human Physiology, University of Zurich, Zurich, Switzerland,
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Human Genetic Adaptation to High Altitude: Evidence from the Andes. Genes (Basel) 2019; 10:genes10020150. [PMID: 30781443 PMCID: PMC6410003 DOI: 10.3390/genes10020150] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 01/29/2019] [Accepted: 02/11/2019] [Indexed: 12/31/2022] Open
Abstract
Whether Andean populations are genetically adapted to high altitudes has long been of interest. Initial studies focused on physiological changes in the O₂ transport system that occur with acclimatization in newcomers and their comparison with those of long-resident Andeans. These as well as more recent studies indicate that Andeans have somewhat larger lung volumes, narrower alveolar to arterial O₂ gradients, slightly less hypoxic pulmonary vasoconstrictor response, greater uterine artery blood flow during pregnancy, and increased cardiac O2 utilization, which overall suggests greater efficiency of O₂ transfer and utilization. More recent single nucleotide polymorphism and whole-genome sequencing studies indicate that multiple gene regions have undergone recent positive selection in Andeans. These include genes involved in the regulation of vascular control, metabolic hemostasis, and erythropoiesis. However, fundamental questions remain regarding the functional links between these adaptive genomic signals and the unique physiological attributes of highland Andeans. Well-designed physiological and genome association studies are needed to address such questions. It will be especially important to incorporate the role of epigenetic processes (i.e.; non-sequence-based features of the genome) that are vital for transcriptional responses to hypoxia and are potentially heritable across generations. In short, further exploration of the interaction among genetic, epigenetic, and environmental factors in shaping patterns of adaptation to high altitude promises to improve the understanding of the mechanisms underlying human adaptive potential and clarify its implications for human health.
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Strewe C, Thieme D, Dangoisse C, Fiedel B, van den Berg F, Bauer H, Salam AP, Gössmann-Lang P, Campolongo P, Moser D, Quintens R, Moreels M, Baatout S, Kohlberg E, Schelling G, Choukèr A, Feuerecker M. Modulations of Neuroendocrine Stress Responses During Confinement in Antarctica and the Role of Hypobaric Hypoxia. Front Physiol 2018; 9:1647. [PMID: 30534078 PMCID: PMC6276713 DOI: 10.3389/fphys.2018.01647] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Accepted: 10/31/2018] [Indexed: 12/12/2022] Open
Abstract
The Antarctic continent is an environment of extreme conditions. Only few research stations exist that are occupied throughout the year. The German station Neumayer III and the French-Italian Concordia station are such research platforms and human outposts. The seasonal shifts of complete daylight (summer) to complete darkness (winter) as well as massive changes in outside temperatures (down to -80°C at Concordia) during winter result in complete confinement of the crews from the outside world. In addition, the crew at Concordia is subjected to hypobaric hypoxia of ∼650 hPa as the station is situated at high altitude (3,233 m). We studied three expedition crews at Neumayer III (sea level) (n = 16) and two at Concordia (high altitude) (n = 15) to determine the effects of hypobaric hypoxia on hormonal/metabolic stress parameters [endocannabinoids (ECs), catecholamines, and glucocorticoids] and evaluated the psychological stress over a period of 11 months including winter confinement. In the Neumayer III (sea level) crew, EC and n-acylethanolamide (NAE) concentrations increased significantly already at the beginning of the deployment (p < 0.001) whereas catecholamines and cortisol remained unaffected. Over the year, ECs and NAEs stayed elevated and fluctuated before slowly decreasing till the end of the deployment. The classical stress hormones showed small increases in the last third of deployment. By contrast, at Concordia (high altitude), norepinephrine concentrations increased significantly at the beginning (p < 0.001) which was paralleled by low EC levels. Prior to the second half of deployment, norepinephrine declined constantly to end on a low plateau level, whereas then the EC concentrations increased significantly in this second period during the overwintering (p < 0.001). Psychometric data showed no significant changes in the crews at either station. These findings demonstrate that exposition of healthy humans to the physically challenging extreme environment of Antarctica (i) has a distinct modulating effect on stress responses. Additionally, (ii) acute high altitude/hypobaric hypoxia at the beginning seem to trigger catecholamine release that downregulates the EC response. These results (iii) are not associated with psychological stress.
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Affiliation(s)
- Claudia Strewe
- Laboratory of Translational Research "Stress and Immunity", Department of Anaesthesiology, University Hospital, LMU Munich, Munich, Germany
| | - Detlef Thieme
- Institute of Doping Analysis and Sports Biochemistry, Dresden, Germany
| | | | - Barbara Fiedel
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany
| | | | - Holger Bauer
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany
| | - Alex P Salam
- IPEV/PNRA-ESA Antarctic Program, Brest, Antarctica
| | - Petra Gössmann-Lang
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany
| | - Patrizia Campolongo
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Dominique Moser
- Laboratory of Translational Research "Stress and Immunity", Department of Anaesthesiology, University Hospital, LMU Munich, Munich, Germany
| | - Roel Quintens
- Radiobiology Unit, Belgian Nuclear Research Centre (SCKCEN), Mol, Belgium
| | - Marjan Moreels
- Radiobiology Unit, Belgian Nuclear Research Centre (SCKCEN), Mol, Belgium
| | - Sarah Baatout
- Radiobiology Unit, Belgian Nuclear Research Centre (SCKCEN), Mol, Belgium.,Department of Molecular Biotechnology, Ghent University, Ghent, Belgium
| | - Eberhard Kohlberg
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany
| | - Gustav Schelling
- Laboratory of Translational Research "Stress and Immunity", Department of Anaesthesiology, University Hospital, LMU Munich, Munich, Germany
| | - Alexander Choukèr
- Laboratory of Translational Research "Stress and Immunity", Department of Anaesthesiology, University Hospital, LMU Munich, Munich, Germany
| | - Matthias Feuerecker
- Laboratory of Translational Research "Stress and Immunity", Department of Anaesthesiology, University Hospital, LMU Munich, Munich, Germany
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Das SK, Dhar P, Sharma VK, Barhwal K, Hota SK, Norboo T, Singh SB. High altitude with monotonous environment has significant impact on mood and cognitive performance of acclimatized lowlanders: Possible role of altered serum BDNF and plasma homocysteine level. J Affect Disord 2018; 237:94-103. [PMID: 29803101 DOI: 10.1016/j.jad.2018.04.106] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Revised: 03/15/2018] [Accepted: 04/08/2018] [Indexed: 10/17/2022]
Abstract
BACKGROUND Monotony resulting due to the wilderness, sparse population and isolation from society could adversely affect human physiology and cause mood alterations. Thus, observations need to be conducted in order to elucidate the possible role of circulating biomarkers in inducing altered mood and cognitive performance following prolonged exposure to high altitude (HA) with persistent monotonous environment. OBJECTIVE The present study aimed towards investigating the impact of monotonous environment in remote HA on mood and cognitive performance of human volunteers and its correlation with serum brain derived neurotrophic factor (BDNF) and plasma homocysteine level. METHODS The present study was conducted on male lowlander participants who had normal social life prior to induction in HA environment. Baseline data was acquired at altitude ≤240 m mean sea level (MSL). Thereafter, the participants were inducted to an altitude of 4500-4800 m MSL. After acclimatization to HA, the participants were assigned as acclimatized low landers (ALL). Longitudinal follow up was conducted after 8 months of high altitude induction on acclimatized low landers (8ALL). Further, to study the effect of monotony, the participants were randomly assigned into different group sizes during their further stay of 4 months in HA viz. ≤5 (12ALL ≤ 5) and ≥10 (12ALL ≥ 10). Mood and cognitive performance of the participants were assessed by standard self-administered questionnaires. Serum BDNF and plasma homocysteine were estimated and their correlation with mood and cognition were determined. RESULTS The findings showed significantly low serum BDNF in 12ALL ≤ 5 group when compared to baseline, 8ALL and 12AL ≥ 10 groups. Alleviated serum BDNF was associated with increased prevalence of mood alterations in HA with persistent monotonous environment. Participants of 12ALL ≥ 10 group showed significantly higher cognitive performance as compared to 12ALL ≤ 5 group which was associated with reduced plasma homocysteine level. LIMITATIONS Total registered volunteers during baseline study were not available during the entire period of this study. The second limitation was exclusion of participants with medical history of severe head injuries, chronic diseases in family and extreme baseline serum profile. Third limitation of the study was to exclude the participants detected with MCI after 8 months of HA induction for negating the role of hypobaric hypoxia on mood and cognition. CONCLUSION The study advocated that ALLs of 12ALL ≤ 5 group have increased prevalence of depressive trait and cognitive impairment which was correlated with reduced serum BDNF and augmented plasma homocysteine level as compared to participants of 12ALL ≥ 10 group having better social interaction with improved cognition and mood. The basic findings of the present study revealed that prolonged HA stay after physiological acclimatization should be regulated by proper social interaction involving normal group size to avoid detrimental effect of monotony and its significant impact on circulatory biomarkers.
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Affiliation(s)
- Saroj Kumar Das
- Defence Institute of High Altitude Research, DRDO, Jammu and Kashmir, India
| | - Priyanka Dhar
- Defence Institute of High Altitude Research, DRDO, Jammu and Kashmir, India
| | - Vijay Kumar Sharma
- Defence Institute of High Altitude Research, DRDO, Jammu and Kashmir, India
| | - Kalpana Barhwal
- Defence Institute of High Altitude Research, DRDO, Jammu and Kashmir, India
| | - Sunil Kumar Hota
- Defence Institute of High Altitude Research, DRDO, Jammu and Kashmir, India
| | - Tsering Norboo
- Ladakh Institute of Prevention, Dambuchan, Leh-Ladakh, Jammu and Kashmir, India
| | - Shashi Bala Singh
- Defence Research and Development Organization, Rajaji Marg, New Delhi, India.
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Differential responses of autonomic function in sea level residents, acclimatized lowlanders at >3500 m and Himalayan high altitude natives at >3500 m: A cross-sectional study. Respir Physiol Neurobiol 2018; 254:40-48. [DOI: 10.1016/j.resp.2018.04.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 04/03/2018] [Accepted: 04/07/2018] [Indexed: 11/22/2022]
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Echoes from Gaea, Poseidon, Hephaestus, and Prometheus: environmental risk factors for high blood pressure. J Hum Hypertens 2018; 32:594-607. [PMID: 29899375 DOI: 10.1038/s41371-018-0078-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 05/01/2018] [Indexed: 12/14/2022]
Abstract
High blood pressure (BP) affects over one billion people and is the leading risk factor for global mortality. While many lifestyle and genetic risk factors are well-accepted to increase BP, the role of the external environment is typically overlooked. Mounting evidence now supports that numerous environmental factors can promote an elevation in BP. Broadly speaking these include aspects of the natural environment (e.g., cold temperatures, higher altitude, and winter season), natural disasters (e.g., earthquakes, volcanic eruptions), and man-made exposures (e.g., noise, air pollutants, and toxins/chemicals). This is important for health care providers to recognize as one (or several) of these environmental factors could be playing a clinically meaningful role in elevating BP or disrupting hypertension control among their patients. At the population level, certain environmental exposures may even be contributing to the growing pandemic of hypertension. Here we provide an updated review of the literature linking environment exposures with high BP and outline practical recommendations for clinicians.
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Prevalence and risk factors of hypertension in acclimatized lowlanders staying at high altitude for different durations. J Hum Hypertens 2018; 32:359-366. [PMID: 29483588 DOI: 10.1038/s41371-018-0037-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 11/21/2017] [Accepted: 12/12/2017] [Indexed: 11/08/2022]
Abstract
Hypoxic exposure at high-altitude (HA) modulates blood pressure (BP). High prevalence of hypertension among native highlanders (NH) has been reported. However, information on prevalence and determinants of hypertension in acclimatized young lowlanders (ALL) staying at HA for different durations is sparse. We aimed to determine the prevalence of hypertension in ALL staying at HA for different durations and its association with cardiovascular risk factors. Male volunteers were categorized on the basis of their duration of stay at HA; Lowlanders (LL) (0 months; n = 151), ALL (1-24 months; n = 519) and NH (n = 103). ALL were sub grouped into ALL 1 (1-6 months; n = 165), ALL 2 (6-12 months; n = 181), and ALL 3 (12-24 months; n = 173). BP, sympathetic activity, arterial stiffness, lipid profile, and homocysteine were estimated. Regression analysis was performed to determine association of risk factors with hypertension. Prevalence of hypertension among ALL was highest with 17.53% followed by NH (11.6%) and LL (9.27%). Prevalence of hypertension in ALL sub group was in order ALL 1 < ALL 2 < ALL 3. Hypertension was significantly associated with sympathetic dominance (p < 0.001) in ALL 1. Hypertension in ALL 2 was associated with dyslipidemia (p < 0.01) while in ALL 3 hypertension was associated with hyperhomocysteinemia (hHCY, p < 0.001), arterial stiffness and dyslipidemia (p < 0.01). In conclusion, our report suggests higher prevalence of hypertension in ALL. The association of studied risk factors and hypertension in different ALL sub groups varied significantly. Our findings suggest the need for a differential clinical approach to control hypertension in ALL considering their duration of stay at HA.
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Effects of aerobic exercise training on ACE and ADRB2 gene expression, plasma angiotensin II level, and flow-mediated dilation: a study on obese postmenopausal women with prehypertension. Menopause 2018; 24:269-277. [PMID: 28231078 DOI: 10.1097/gme.0000000000000762] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVE The purpose of this study is to determine the effect of 10 weeks of moderate-intensity aerobic exercise training (MIET) on blood pressure (BP), angiotensin-converting enzyme (ACE) and β2-adrenergic receptor (ADRB2) gene expression in leukocytes, plasma angiotensin II (Ang II), and flow-mediated dilation (FMD) in obese postmenopausal women (PMW) with prehypertension. METHODS Twenty-four obese prehypertensive PMW (aged 50-70 y; body mass index ≥30 kg/m) randomly assigned to control (n = 12) and exercise (n = 12) groups. Exercise group performed MIET (25-40 min/d, 3 d/wk at 50%-70% of heart rate reserve) for 10 weeks. Control group maintained their normal daily physical activity level. Body composition, VO2max, BP, ACE and ADRB2 gene expression, plasma Ang II, and FMD were measured before and after the training program. RESULTS After MIET, systolic and diastolic BPs decreased by 4.6% and 2.4%, respectively (P < 0.001). Plasma Ang II level decreased by 45.7%, whereas FMD increased by 86% in the exercise group (P < 0.001). Exercise training resulted in a threefold increase in ADRB2 and a fourfold decrease in ACE gene expressions (P < 0.05). Training-induced changes in BP inversely associated with the changes in FMD and ADRB2 (r values range -0.55 to -0.78), and positively associated with Ang II and ACE (r values range 0.68-0.86) (P < 0.001). CONCLUSIONS Ten weeks of MIET modulates ACE and ADRB2 gene expression, decreases Ang II plasma levels, and improves endothelial function in obese PMW, and these alterations are associated with reduction in BP.
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Moore LG. Measuring high-altitude adaptation. J Appl Physiol (1985) 2017; 123:1371-1385. [PMID: 28860167 DOI: 10.1152/japplphysiol.00321.2017] [Citation(s) in RCA: 105] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 08/15/2017] [Accepted: 08/15/2017] [Indexed: 12/12/2022] Open
Abstract
High altitudes (>8,000 ft or 2,500 m) provide an experiment of nature for measuring adaptation and the physiological processes involved. Studies conducted over the past ~25 years in Andeans, Tibetans, and, less often, Ethiopians show varied but distinct O2 transport traits from those of acclimatized newcomers, providing indirect evidence for genetic adaptation to high altitude. Short-term (acclimatization, developmental) and long-term (genetic) responses to high altitude exhibit a temporal gradient such that, although all influence O2 content, the latter also improve O2 delivery and metabolism. Much has been learned concerning the underlying physiological processes, but additional studies are needed on the regulation of blood flow and O2 utilization. Direct evidence of genetic adaptation comes from single-nucleotide polymorphism (SNP)-based genome scans and whole genome sequencing studies that have identified gene regions acted upon by natural selection. Efforts have begun to understand the connections between the two with Andean studies on the genetic factors raising uterine blood flow, fetal growth, and susceptibility to Chronic Mountain Sickness and Tibetan studies on genes serving to lower hemoglobin and pulmonary arterial pressure. Critical for future studies will be the selection of phenotypes with demonstrable effects on reproductive success, the calculation of actual fitness costs, and greater inclusion of women among the subjects being studied. The well-characterized nature of the O2 transport system, the presence of multiple long-resident populations, and relevance for understanding hypoxic disorders in all persons underscore the importance of understanding how evolutionary adaptation to high altitude has occurred.NEW & NOTEWORTHY Variation in O2 transport characteristics among Andean, Tibetan, and, when available, Ethiopian high-altitude residents supports the existence of genetic adaptations that improve the distribution of blood flow to vital organs and the efficiency of O2 utilization. Genome scans and whole genome sequencing studies implicate a broad range of gene regions. Future studies are needed using phenotypes of clear relevance for reproductive success for determining the mechanisms by which naturally selected genes are acting.
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Affiliation(s)
- Lorna G Moore
- Division of Reproductive Sciences, Department of Obstetrics & Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
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Kurdziel M, Wasilewski J, Gierszewska K, Kazik A, Pytel G, Wacławski J, Krajewski A, Kurek A, Poloński L, Gąsior M. Echocardiographic Assessment of Right Ventricle Dimensions and Function After Exposure to Extreme Altitude: Is an Expedition to 8000 m Hazardous for Right Ventricular Function? High Alt Med Biol 2017; 18:330-337. [PMID: 28816526 DOI: 10.1089/ham.2017.0019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Kurdziel, Marta, Jarosław Wasilewski, Karolina Gierszewska, Anna Kazik, Gracjan Pytel, Jacek Wacławski, Adam Krajewski, Anna Kurek, Lech Poloński, and Mariusz Gąsior. Echocardiographic assessment of right ventricle dimensions and function after exposure to extreme altitude: Is an expedition to 8000 m hazardous for right ventricular function? High Alt Med Biol 18:330-337, 2017.-Although the right ventricle (RV) is under great hypoxic stress at altitude, still little is known what happens to the RV after descent. The aim of this study was to evaluate RV dimensions and function after exposure to extreme altitude. Therefore, echocardiographic examination was performed according to a protocol that focused on the RV in 11 healthy subjects participating in an expedition to K2 (8611 m) or Broad Peak (BP, 8051 m). In comparison to measurements before the expedition, after 7-8 weeks of sojourn above 2300 meters with the aim of climbing K2 and BP, the RV Tei index increased (0.5 ± 0.1 vs. 0.4 ± 0.1; p = 0.028), and RV free wall longitudinal systolic strain (RVFWLSS) decreased (-23.1% ± 2.7% vs. -25.9% ± 2.4%; p = 0.043). Decrease in peak systolic strain and strain rate was observed in the basal and mid segments of the RV free wall (respectively: -24.4% ± 4.4% vs. -30.9% ± 6.5%; -1.4 ± 0.3 s-1 vs. -1.8 ± 0.3 s-1; -28.7% ± 3.9% vs. -34% ± 3.3%; -1.5 ± 0.2 s-1 vs. -1.9 ± 0.3 s-1; p for all <0.05). The linear RV dimensions, the proximal and distal RV outflow tracks, increased (respectively: 31.3 ± 4 mm vs. 29.2 ± 3 mm, p = 0.025; 27 ± 2.7 mm vs. 24.8 ± 3 mm, p = 0.012). We found that exposure to extreme altitude may cause RV dilatation and a decrease in RV performance. The Tei index and RVFWLSS are sensitive performance indices to detect changes in RV function after the exposure to hypoxic stress. The observed alterations seem to be a manifestation of physiological adaptation to high-altitude condition in healthy individuals.
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Affiliation(s)
- Marta Kurdziel
- 1 3rd Department of Cardiology, School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia , Katowice, Poland .,2 Silesian Center for Heart Diseases , Zabrze, Poland
| | - Jarosław Wasilewski
- 1 3rd Department of Cardiology, School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia , Katowice, Poland .,2 Silesian Center for Heart Diseases , Zabrze, Poland
| | - Karolina Gierszewska
- 1 3rd Department of Cardiology, School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia , Katowice, Poland .,2 Silesian Center for Heart Diseases , Zabrze, Poland
| | - Anna Kazik
- 1 3rd Department of Cardiology, School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia , Katowice, Poland .,2 Silesian Center for Heart Diseases , Zabrze, Poland
| | - Gracjan Pytel
- 1 3rd Department of Cardiology, School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia , Katowice, Poland .,2 Silesian Center for Heart Diseases , Zabrze, Poland
| | - Jacek Wacławski
- 1 3rd Department of Cardiology, School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia , Katowice, Poland .,2 Silesian Center for Heart Diseases , Zabrze, Poland
| | - Adam Krajewski
- 1 3rd Department of Cardiology, School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia , Katowice, Poland .,2 Silesian Center for Heart Diseases , Zabrze, Poland
| | - Anna Kurek
- 1 3rd Department of Cardiology, School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia , Katowice, Poland .,2 Silesian Center for Heart Diseases , Zabrze, Poland
| | - Lech Poloński
- 1 3rd Department of Cardiology, School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia , Katowice, Poland .,2 Silesian Center for Heart Diseases , Zabrze, Poland
| | - Mariusz Gąsior
- 1 3rd Department of Cardiology, School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia , Katowice, Poland .,2 Silesian Center for Heart Diseases , Zabrze, Poland
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Siebenmann C, Rasmussen P, Hug M, Keiser S, Flück D, Fisher JP, Hilty MP, Maggiorini M, Lundby C. Parasympathetic withdrawal increases heart rate after 2 weeks at 3454 m altitude. J Physiol 2017; 595:1619-1626. [PMID: 27966225 DOI: 10.1113/jp273726] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 11/21/2016] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Heart rate is increased in chronic hypoxia and we tested whether this is the result of increased sympathetic nervous activity, reduced parasympathetic nervous activity, or a non-autonomic mechanism. In seven lowlanders, heart rate was measured at sea level and after 2 weeks at high altitude after individual and combined pharmacological inhibition of sympathetic and/or parasympathetic control of the heart. Inhibition of parasympathetic control of the heart alone or in combination with inhibition of sympathetic control abolished the high altitude-induced increase in heart rate. Inhibition of sympathetic control of the heart alone did not prevent the high altitude-induced increase in heart rate. These results indicate that a reduced parasympathetic nervous activity is the main mechanism underlying the elevated heart rate in chronic hypoxia. ABSTRACT Chronic hypoxia increases resting heart rate (HR), but the underlying mechanism remains incompletely understood. We investigated the relative contributions of the sympathetic and parasympathetic nervous systems, along with potential non-autonomic mechanisms, by individual and combined pharmacological inhibition of muscarinic and/or β-adrenergic receptors. In seven healthy lowlanders, resting HR was determined at sea level (SL) and after 15-18 days of exposure to 3454 m high altitude (HA) without drug intervention (control, CONT) as well as after intravenous administration of either propranolol (PROP), or glycopyrrolate (GLYC), or PROP and GLYC in combination (PROP+GLYC). Circulating noradrenaline concentration increased from 0.9 ± 0.4 nmol l-1 at SL to 2.7 ± 1.5 nmol l-1 at HA (P = 0.03). The effect of HA on HR depended on the type of autonomic inhibition (P = 0.006). Specifically, HR was increased at HA from 64 ± 10 to 74 ± 12 beats min-1 during the CONT treatment (P = 0.007) and from 52 ± 4 to 59 ± 5 beats min-1 during the PROP treatment (P < 0.001). In contrast, HR was similar between SL and HA during the GLYC treatment (110 ± 7 and 112 ± 5 beats min-1 , P = 0.28) and PROP+GLYC treatment (83 ± 5 and 85 ± 5 beats min-1 , P = 0.25). Our results identify a reduction in cardiac parasympathetic activity as the primary mechanism underlying the elevated HR associated with 2 weeks of exposure to hypoxia. Unexpectedly, the sympathoactivation at HA that was evidenced by increased circulating noradrenaline concentration had little effect on HR, potentially reflecting down-regulation of cardiac β-adrenergic receptor function in chronic hypoxia. These effects of chronic hypoxia on autonomic control of the heart may concern not only HA dwellers, but also patients with disorders that are associated with hypoxaemia.
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Affiliation(s)
- Christoph Siebenmann
- Centre for Integrative Human Physiology, Institute of Physiology, University of Zürich, Zürich, Switzerland.,Department of Environmental Physiology, School of Technology and Health, Royal Institute of Technology, Solna, Sweden
| | - Peter Rasmussen
- Centre for Integrative Human Physiology, Institute of Physiology, University of Zürich, Zürich, Switzerland.,H. Lundbeck A/S, Valby, Denmark
| | - Mike Hug
- Centre for Integrative Human Physiology, Institute of Physiology, University of Zürich, Zürich, Switzerland
| | - Stefanie Keiser
- Centre for Integrative Human Physiology, Institute of Physiology, University of Zürich, Zürich, Switzerland
| | - Daniela Flück
- Centre for Integrative Human Physiology, Institute of Physiology, University of Zürich, Zürich, Switzerland
| | - James P Fisher
- School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Matthias P Hilty
- Intensive Care Unit, University Hospital of Zürich, Zürich, Switzerland
| | - Marco Maggiorini
- Intensive Care Unit, University Hospital of Zürich, Zürich, Switzerland
| | - Carsten Lundby
- Centre for Integrative Human Physiology, Institute of Physiology, University of Zürich, Zürich, Switzerland
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Yu L, Chen Y, Wang W, Xiao Z, Hong Y. Multi-Vitamin B Supplementation Reverses Hypoxia-Induced Tau Hyperphosphorylation and Improves Memory Function in Adult Mice. J Alzheimers Dis 2016; 54:297-306. [DOI: 10.3233/jad-160329] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Krejčí J, Botek M, McKune AJ. Dynamics of the heart rate variability and oxygen saturation response to acute normobaric hypoxia within the first 10 min of exposure. Clin Physiol Funct Imaging 2016; 38:56-62. [DOI: 10.1111/cpf.12381] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 06/06/2016] [Indexed: 11/28/2022]
Affiliation(s)
- Jakub Krejčí
- Department of Natural Sciences in Kinanthropology; Faculty of Physical Culture; Palacký University Olomouc; Olomouc Czech Republic
| | - Michal Botek
- Department of Natural Sciences in Kinanthropology; Faculty of Physical Culture; Palacký University Olomouc; Olomouc Czech Republic
| | - Andrew J. McKune
- Discipline of Sport and Exercise Science; Faculty of Health; UC-Research Institute for Sport and Exercise; University of Canberra; Canberra ACT Australia
- Discipline of Biokinetics; Exercise and Leisure Sciences; School of Health Sciences; University of KwaZulu-Natal; Durban South Africa
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33
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Siebenmann C, Lundby C. Regulation of cardiac output in hypoxia. Scand J Med Sci Sports 2015; 25 Suppl 4:53-9. [DOI: 10.1111/sms.12619] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/14/2015] [Indexed: 10/22/2022]
Affiliation(s)
- Christoph Siebenmann
- Department of Environmental Physiology; School of Technology and Health; Royal Institute of Technology; Solna Sweden
| | - Carsten Lundby
- Center for Integrative Human Physiology; Institute of Physiology; University of Zürich; Zürich Switzerland
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Woolcott OO, Ader M, Bergman RN. Glucose homeostasis during short-term and prolonged exposure to high altitudes. Endocr Rev 2015; 36:149-73. [PMID: 25675133 PMCID: PMC4399271 DOI: 10.1210/er.2014-1063] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Most of the literature related to high altitude medicine is devoted to the short-term effects of high-altitude exposure on human physiology. However, long-term effects of living at high altitudes may be more important in relation to human disease because more than 400 million people worldwide reside above 1500 m. Interestingly, individuals living at higher altitudes have a lower fasting glycemia and better glucose tolerance compared with those who live near sea level. There is also emerging evidence of the lower prevalence of both obesity and diabetes at higher altitudes. The mechanisms underlying improved glucose control at higher altitudes remain unclear. In this review, we present the most current evidence about glucose homeostasis in residents living above 1500 m and discuss possible mechanisms that could explain the lower fasting glycemia and lower prevalence of obesity and diabetes in this population. Understanding the mechanisms that regulate and maintain the lower fasting glycemia in individuals who live at higher altitudes could lead to new therapeutics for impaired glucose homeostasis.
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Affiliation(s)
- Orison O Woolcott
- Diabetes and Obesity Research Institute, Cedars-Sinai Medical Center, Los Angeles, California 90048
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35
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Ivy CM, Scott GR. Control of breathing and the circulation in high-altitude mammals and birds. Comp Biochem Physiol A Mol Integr Physiol 2014; 186:66-74. [PMID: 25446936 DOI: 10.1016/j.cbpa.2014.10.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 10/17/2014] [Accepted: 10/18/2014] [Indexed: 01/07/2023]
Abstract
Hypoxia is an unremitting stressor at high altitudes that places a premium on oxygen transport by the respiratory and cardiovascular systems. Phenotypic plasticity and genotypic adaptation at various steps in the O2 cascade could help offset the effects of hypoxia on cellular O2 supply in high-altitude natives. In this review, we will discuss the unique mechanisms by which ventilation, cardiac output, and blood flow are controlled in high-altitude mammals and birds. Acclimatization to high altitudes leads to some changes in respiratory and cardiovascular control that increase O2 transport in hypoxia (e.g., ventilatory acclimatization to hypoxia). However, acclimatization or development in hypoxia can also modify cardiorespiratory control in ways that are maladaptive for O2 transport. Hypoxia responses that arose as short-term solutions to O2 deprivation (e.g., peripheral vasoconstriction) or regional variation in O2 levels in the lungs (i.e., hypoxic pulmonary vasoconstriction) are detrimental at in chronic high-altitude hypoxia. Evolved changes in cardiorespiratory control have arisen in many high-altitude taxa, including increases in effective ventilation, attenuation of hypoxic pulmonary vasoconstriction, and changes in catecholamine sensitivity of the heart and systemic vasculature. Parallel evolution of some of these changes in independent highland lineages supports their adaptive significance. Much less is known about the genomic bases and potential interactive effects of adaptation, acclimatization, developmental plasticity, and trans-generational epigenetic transfer on cardiorespiratory control. Future work to understand these various influences on breathing and circulation in high-altitude natives will help elucidate how complex physiological systems can be pushed to their limits to maintain cellular function in hypoxia.
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Affiliation(s)
- Catherine M Ivy
- Department of Biology, McMaster University, Hamilton, ON, Canada.
| | - Graham R Scott
- Department of Biology, McMaster University, Hamilton, ON, Canada
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