1
|
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.
Collapse
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
| |
Collapse
|
2
|
Ye X, Sun M, Yu S, Yang J, Liu Z, Lv H, Wu B, He J, Wang X, Huang L. Smartwatch-Based Maximum Oxygen Consumption Measurement for Predicting Acute Mountain Sickness: Diagnostic Accuracy Evaluation Study. JMIR Mhealth Uhealth 2023; 11:e43340. [PMID: 37410528 PMCID: PMC10360014 DOI: 10.2196/43340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 12/11/2022] [Accepted: 06/09/2023] [Indexed: 07/07/2023] Open
Abstract
BACKGROUND Cardiorespiratory fitness plays an important role in coping with hypoxic stress at high altitudes. However, the association of cardiorespiratory fitness with the development of acute mountain sickness (AMS) has not yet been evaluated. Wearable technology devices provide a feasible assessment of cardiorespiratory fitness, which is quantifiable as maximum oxygen consumption (VO2max) and may contribute to AMS prediction. OBJECTIVE We aimed to determine the validity of VO2max estimated by the smartwatch test (SWT), which can be self-administered, in order to overcome the limitations of clinical VO2max measurements. We also aimed to evaluate the performance of a VO2max-SWT-based model in predicting susceptibility to AMS. METHODS Both SWT and cardiopulmonary exercise test (CPET) were performed for VO2max measurements in 46 healthy participants at low altitude (300 m) and in 41 of them at high altitude (3900 m). The characteristics of the red blood cells and hemoglobin levels in all the participants were analyzed by routine blood examination before the exercise tests. The Bland-Altman method was used for bias and precision assessment. Multivariate logistic regression was performed to analyze the correlation between AMS and the candidate variables. A receiver operating characteristic curve was used to evaluate the efficacy of VO2max in predicting AMS. RESULTS VO2max decreased after acute high altitude exposure, as measured by CPET (25.20 [SD 6.46] vs 30.17 [SD 5.01] at low altitude; P<.001) and SWT (26.17 [SD 6.71] vs 31.28 [SD 5.17] at low altitude; P<.001). Both at low and high altitudes, VO2max was slightly overestimated by SWT but had considerable accuracy as the mean absolute percentage error (<7%) and mean absolute error (<2 mL·kg-1·min-1), with a relatively small bias compared with VO2max-CPET. Twenty of the 46 participants developed AMS at 3900 m, and their VO2max was significantly lower than that of those without AMS (CPET: 27.80 [SD 4.55] vs 32.00 [SD 4.64], respectively; P=.004; SWT: 28.00 [IQR 25.25-32.00] vs 32.00 [IQR 30.00-37.00], respectively; P=.001). VO2max-CPET, VO2max-SWT, and red blood cell distribution width-coefficient of variation (RDW-CV) were found to be independent predictors of AMS. To increase the prediction accuracy, we used combination models. The combination of VO2max-SWT and RDW-CV showed the largest area under the curve for all parameters and models, which increased the area under the curve from 0.785 for VO2max-SWT alone to 0.839. CONCLUSIONS Our study demonstrates that the smartwatch device can be a feasible approach for estimating VO2max. In both low and high altitudes, VO2max-SWT showed a systematic bias toward a calibration point, slightly overestimating the proper VO2max when investigated in healthy participants. The SWT-based VO2max at low altitude is an effective indicator of AMS and helps to better identify susceptible individuals following acute high-altitude exposure, particularly by combining the RDW-CV at low altitude. TRIAL REGISTRATION Chinese Clinical Trial Registry ChiCTR2200059900; https://www.chictr.org.cn/showproj.html?proj=170253.
Collapse
Affiliation(s)
- Xiaowei Ye
- Institute of Cardiovascular Diseases of People's Liberation Army, The Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Mengjia Sun
- Institute of Cardiovascular Diseases of People's Liberation Army, The Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Shiyong Yu
- Institute of Cardiovascular Diseases of People's Liberation Army, The Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Jie Yang
- Institute of Cardiovascular Diseases of People's Liberation Army, The Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Zhen Liu
- Institute of Cardiovascular Diseases of People's Liberation Army, The Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Hailin Lv
- Institute of Cardiovascular Diseases of People's Liberation Army, The Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Boji Wu
- Institute of Cardiovascular Diseases of People's Liberation Army, The Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Jingyu He
- Institute of Cardiovascular Diseases of People's Liberation Army, The Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Xuhong Wang
- Institute of Cardiovascular Diseases of People's Liberation Army, The Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Lan Huang
- Institute of Cardiovascular Diseases of People's Liberation Army, The Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| |
Collapse
|
3
|
Zhang X, Jia X, Wang S, Xin J, Sun N, Wang Y, Zhang X, Wan Z, Fan J, Li H, Bai Y, Ni X, Huang Y, Wang H, Ma H. Disrupted gut microbiota aggravates spatial memory dysfunction induced by high altitude exposure: A link between plateau environment and microbiome-gut-brain axis. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 259:115035. [PMID: 37224779 DOI: 10.1016/j.ecoenv.2023.115035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 04/11/2023] [Accepted: 05/17/2023] [Indexed: 05/26/2023]
Abstract
Approximately 400 million people work and live in high-altitude areas and suffer from memory dysfunction worldwide. Until now, the role of the intestinal flora in plateau-induced brain damage has rarely been reported. To address this, we investigated the effect of intestinal flora on spatial memory impairment induced by high altitudes based on the microbiome-gut-brain axis theory. C57BL/6 mice were divided into three groups: control, high-altitude (HA), and high-altitude antibiotic treatment (HAA) group. The HA and HAA groups were exposed to a low-pressure oxygen chamber that simulated an altitude of 4000 m above sea level (m. a. s.l.) for 14 days, with the air pressure in the chamber set at 60-65 kPa. The results showed that spatial memory dysfunction induced by the high-altitude environment was aggravated by antibiotic treatment, manifesting as lowered escape latency and hippocampal memory-related proteins (BDNF and PSD-95). 16 S rRNA sequencing showed a remarkable separation of the ileal microbiota among the three groups. Antibiotic treatment exacerbated the reduced richness and diversity of the ileal microbiota in mice in the HA group. Lactobacillaceae were the main target bacteria and were significantly reduced in the HA group, which was exacerbated by antibiotic treatment. Meanwhile, reduced intestinal permeability and ileal immune function in mice exposed high-altitude environment was also aggravated by antibiotic treatment, as indicated by the lowered tight junction proteins and IL-1β and IFN-γ levels. Furthermore, indicator species analysis and Netshift co-analysis revealed that Lactobacillaceae (ASV11) and Corynebacteriaceae (ASV78, ASV25, and ASV47) play important roles in high-altitude exposure-induced memory dysfunction. Interestingly, ASV78 was negatively correlated with IL-1β and IFN-γ levels, indicating that ASV78 may be induced by reduced ileal immune function, which mediates high-altitude environment exposure-induced memory dysfunction. This study provides evidence that the intestinal flora is effective in preventing brain dysfunction caused by exposure to high-altitude environments, suggesting a relationship between the microbiome-gut-brain axis and altitude exposure.
Collapse
Affiliation(s)
- Xufei Zhang
- Plateau Brain Science Research Center, Tibet University, Lhasa, Tibet, China
| | - Xianhao Jia
- Plateau Brain Science Research Center, Tibet University, Lhasa, Tibet, China
| | - Shengnan Wang
- Baiyun Branch, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Jinge Xin
- Baiyun Branch, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China; Guangzhou Beneco biotechnology Co. Ltd., Guangzhou, Guangdong, China
| | - Ning Sun
- Animal Microecology Institute, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Yanyan Wang
- Animal Microecology Institute, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Xingting Zhang
- Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Institute of Gastroenterology of Guangdong Province, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Zhiqiang Wan
- Animal Microecology Institute, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Jing Fan
- Plateau Brain Science Research Center, Tibet University, Lhasa, Tibet, China
| | - Hao Li
- Plateau Brain Science Research Center, Tibet University, Lhasa, Tibet, China
| | - Yang Bai
- Baiyun Branch, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Institute of Gastroenterology of Guangdong Province, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Xueqin Ni
- Animal Microecology Institute, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Yongmei Huang
- Baiyun Branch, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China.
| | - Hesong Wang
- Baiyun Branch, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China.
| | - Hailin Ma
- Plateau Brain Science Research Center, Tibet University, Lhasa, Tibet, China.
| |
Collapse
|
4
|
Samaja M, Ottolenghi S. The Oxygen Cascade from Atmosphere to Mitochondria as a Tool to Understand the (Mal)adaptation to Hypoxia. Int J Mol Sci 2023; 24:ijms24043670. [PMID: 36835089 PMCID: PMC9960749 DOI: 10.3390/ijms24043670] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 02/05/2023] [Accepted: 02/09/2023] [Indexed: 02/15/2023] Open
Abstract
Hypoxia is a life-threatening challenge for about 1% of the world population, as well as a contributor to high morbidity and mortality scores in patients affected by various cardiopulmonary, hematological, and circulatory diseases. However, the adaptation to hypoxia represents a failure for a relevant portion of the cases as the pathways of potential adaptation often conflict with well-being and generate diseases that in certain areas of the world still afflict up to one-third of the populations living at altitude. To help understand the mechanisms of adaptation and maladaptation, this review examines the various steps of the oxygen cascade from the atmosphere to the mitochondria distinguishing the patterns related to physiological (i.e., due to altitude) and pathological (i.e., due to a pre-existing disease) hypoxia. The aim is to assess the ability of humans to adapt to hypoxia in a multidisciplinary approach that correlates the function of genes, molecules, and cells with the physiologic and pathological outcomes. We conclude that, in most cases, it is not hypoxia by itself that generates diseases, but rather the attempts to adapt to the hypoxia condition. This underlies the paradigm shift that when adaptation to hypoxia becomes excessive, it translates into maladaptation.
Collapse
Affiliation(s)
- Michele Samaja
- MAGI GROUP, San Felice del Benaco, 25010 Brescia, Italy
- Correspondence:
| | - Sara Ottolenghi
- School of Medicine and Surgery, University of Milano Bicocca, 20126 Milan, Italy
| |
Collapse
|
5
|
Lloyd AB, Havenith G. Reply to Richalet and Hermand. Updating the CVR model for limitations in maximum myocardial contractility at high altitude. J Appl Physiol (1985) 2023; 134:148-149. [PMID: 36592409 DOI: 10.1152/japplphysiol.00678.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Affiliation(s)
- Alex B Lloyd
- Environmental Ergonomics Research Centre, Loughborough University, Loughborough, United Kingdom
| | - George Havenith
- Environmental Ergonomics Research Centre, Loughborough University, Loughborough, United Kingdom
| |
Collapse
|
6
|
Fabries P, Gomez-Merino D, Sauvet F, Malgoyre A, Koulmann N, Chennaoui M. Sleep loss effects on physiological and cognitive responses to systemic environmental hypoxia. Front Physiol 2022; 13:1046166. [PMID: 36579023 PMCID: PMC9792101 DOI: 10.3389/fphys.2022.1046166] [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: 09/30/2022] [Accepted: 11/29/2022] [Indexed: 12/15/2022] Open
Abstract
In the course of their missions or training, alpinists, but also mountain combat forces and mountain security services, professional miners, aircrew, aircraft and glider pilots and helicopter crews are regularly exposed to altitude without oxygen supplementation. At altitude, humans are exposed to systemic environmental hypoxia induced by the decrease in barometric pressure (<1,013 hPa) which decreases the inspired partial pressure of oxygen (PIO2), while the oxygen fraction is constant (equal to approximately 20.9%). Effects of altitude on humans occur gradually and depend on the duration of exposure and the altitude level. From 1,500 m altitude (response threshold), several adaptive responses offset the effects of hypoxia, involving the respiratory and the cardiovascular systems, and the oxygen transport capacity of the blood. Fatigue and cognitive and sensory disorders are usually observed from 2,500 m (threshold of prolonged hypoxia). Above 3,500 m (the threshold for disorders), the effects are not completely compensated and maladaptive responses occur and individuals develop altitude headache or acute altitude illness [Acute Mountain Sickness (AMS)]. The magnitude of effects varies considerably between different physiological systems and exhibits significant inter-individual variability. In addition to comorbidities, the factors of vulnerability are still little known. They can be constitutive (genetic) or circumstantial (sleep deprivation, fatigue, speed of ascent.). In particular, sleep loss, a condition that is often encountered in real-life settings, could have an impact on the physiological and cognitive responses to hypoxia. In this review, we report the current state of knowledge on the impact of sleep loss on responses to environmental hypoxia in humans, with the aim of identifying possible consequences for AMS risk and cognition, as well as the value of behavioral and non-pharmacological countermeasures.
Collapse
Affiliation(s)
- Pierre Fabries
- REF-Aero Department, French Armed Forces Biomedical Research Institute—IRBA, Brétigny-sur-Orge, France,Laboratoire de Biologie de l’Exercice pour la Performance et la Santé (LBEPS), UMR, Université Paris-Saclay, IRBA, Evry-Courcouronnes, France,French Military Health Academy—Ecole du Val-de-Grâce, Place Alphonse Laveran, Paris, France,*Correspondence: Pierre Fabries,
| | - Danielle Gomez-Merino
- REF-Aero Department, French Armed Forces Biomedical Research Institute—IRBA, Brétigny-sur-Orge, France,Vigilance Fatigue Sommeil et Santé Publique (VIFASOM) URP 7330, Université de Paris Cité, Paris, France
| | - Fabien Sauvet
- REF-Aero Department, French Armed Forces Biomedical Research Institute—IRBA, Brétigny-sur-Orge, France,French Military Health Academy—Ecole du Val-de-Grâce, Place Alphonse Laveran, Paris, France,Vigilance Fatigue Sommeil et Santé Publique (VIFASOM) URP 7330, Université de Paris Cité, Paris, France
| | - Alexandra Malgoyre
- REF-Aero Department, French Armed Forces Biomedical Research Institute—IRBA, Brétigny-sur-Orge, France,Laboratoire de Biologie de l’Exercice pour la Performance et la Santé (LBEPS), UMR, Université Paris-Saclay, IRBA, Evry-Courcouronnes, France
| | - Nathalie Koulmann
- Laboratoire de Biologie de l’Exercice pour la Performance et la Santé (LBEPS), UMR, Université Paris-Saclay, IRBA, Evry-Courcouronnes, France,French Military Health Academy—Ecole du Val-de-Grâce, Place Alphonse Laveran, Paris, France
| | - Mounir Chennaoui
- REF-Aero Department, French Armed Forces Biomedical Research Institute—IRBA, Brétigny-sur-Orge, France,Vigilance Fatigue Sommeil et Santé Publique (VIFASOM) URP 7330, Université de Paris Cité, Paris, France
| |
Collapse
|
7
|
Fabries P, Drogou C, Sauvet F, Nespoulous O, Erkel MC, Marchandot V, Bouaziz W, Lepetit B, Hamm-Hornez AP, Malgoyre A, Koulmann N, Gomez-Merino D, Chennaoui M. The HMOX2 polymorphism contributes to the carotid body chemoreflex in European sea-level residents by regulating hypoxic ventilatory responses. Front Med (Lausanne) 2022; 9:1000786. [PMID: 36405624 PMCID: PMC9669423 DOI: 10.3389/fmed.2022.1000786] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 10/17/2022] [Indexed: 10/18/2023] Open
Abstract
This study investigates whether a functional single nucleotide polymorphism of HMOX2 (heme oxygenase-2) (rs4786504 T>C) is involved in individual chemosensitivity to acute hypoxia, as assessed by ventilatory responses, in European individuals. These responses were obtained at rest and during submaximal exercise, using a standardized and validated protocol for exposure to acute normobaric hypoxia. Carriers of the ancestral T allele (n = 44) have significantly lower resting and exercise hypoxic ventilatory responses than C/C homozygous carriers (n = 40). In the literature, a hypoxic ventilatory response threshold to exercise has been identified as an independent predictor of severe high altitude-illness (SHAI). Our study shows that carriers of the T allele have a higher risk of SHAI than carriers of the mutated C/C genotype. Secondarily, we were also interested in COMT (rs4680 G > A) polymorphism, which may be indirectly involved in the chemoreflex response through modulation of autonomic nervous system activity. Significant differences are present between COMT genotypes for oxygen saturation and ventilatory responses to hypoxia at rest. In conclusion, this study adds information on genetic factors involved in individual vulnerability to acute hypoxia and supports the critical role of the ≪ O2 sensor ≫ - heme oxygenase-2 - in the chemosensitivity of carotid bodies in Humans.
Collapse
Affiliation(s)
- Pierre Fabries
- French Armed Forces Biomedical Research Institute – IRBA, Brétigny-sur-Orge, France
- French Military Health Academy - Ecole du Val-de-Grâce, Paris, France
- Laboratoire de Biologie de l'Exercice pour la Performance et la Santé – LBEPS – UMR, Université Paris-Saclay, IRBA, Evry-Courcouronnes, France
| | - Catherine Drogou
- French Armed Forces Biomedical Research Institute – IRBA, Brétigny-sur-Orge, France
- Vigilance Fatigue Sommeil et Santé Publique – VIFASOM – UPR 7330, Université de Paris Cité, Paris, France
| | - Fabien Sauvet
- French Armed Forces Biomedical Research Institute – IRBA, Brétigny-sur-Orge, France
- French Military Health Academy - Ecole du Val-de-Grâce, Paris, France
- Vigilance Fatigue Sommeil et Santé Publique – VIFASOM – UPR 7330, Université de Paris Cité, Paris, France
| | - Olivier Nespoulous
- French Armed Forces Biomedical Research Institute – IRBA, Brétigny-sur-Orge, France
| | - Marie-Claire Erkel
- French Armed Forces Biomedical Research Institute – IRBA, Brétigny-sur-Orge, France
- Vigilance Fatigue Sommeil et Santé Publique – VIFASOM – UPR 7330, Université de Paris Cité, Paris, France
| | | | - Walid Bouaziz
- French Armed Forces Biomedical Research Institute – IRBA, Brétigny-sur-Orge, France
| | - Benoît Lepetit
- French Armed Forces Biomedical Research Institute – IRBA, Brétigny-sur-Orge, France
- Laboratoire de Biologie de l'Exercice pour la Performance et la Santé – LBEPS – UMR, Université Paris-Saclay, IRBA, Evry-Courcouronnes, France
| | | | - Alexandra Malgoyre
- French Armed Forces Biomedical Research Institute – IRBA, Brétigny-sur-Orge, France
- Laboratoire de Biologie de l'Exercice pour la Performance et la Santé – LBEPS – UMR, Université Paris-Saclay, IRBA, Evry-Courcouronnes, France
| | - Nathalie Koulmann
- French Military Health Academy - Ecole du Val-de-Grâce, Paris, France
- Laboratoire de Biologie de l'Exercice pour la Performance et la Santé – LBEPS – UMR, Université Paris-Saclay, IRBA, Evry-Courcouronnes, France
| | - Danielle Gomez-Merino
- French Armed Forces Biomedical Research Institute – IRBA, Brétigny-sur-Orge, France
- Vigilance Fatigue Sommeil et Santé Publique – VIFASOM – UPR 7330, Université de Paris Cité, Paris, France
| | - Mounir Chennaoui
- French Armed Forces Biomedical Research Institute – IRBA, Brétigny-sur-Orge, France
- Vigilance Fatigue Sommeil et Santé Publique – VIFASOM – UPR 7330, Université de Paris Cité, Paris, France
| |
Collapse
|
8
|
Chanana N, Palmo T, Sharma K, Kumar R, Shah B, Mahajan S, Palleda GM, Gupta MD, Kukreti R, Faruq M, Thinlas T, Graham BB, Pasha Q. Sexual Dimorphism of Dexamethasone as a Prophylactic Treatment in Pathologies Associated With Acute Hypobaric Hypoxia Exposure. Front Pharmacol 2022; 13:873867. [PMID: 35668947 PMCID: PMC9163683 DOI: 10.3389/fphar.2022.873867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 04/05/2022] [Indexed: 11/21/2022] Open
Abstract
Dexamethasone can be taken prophylactically to prevent hypobaric hypoxia-associated disorders of high-altitude. While dexamethasone-mediated protection against high-altitude disorders has been clinically evaluated, detailed sex-based mechanistic insights have not been explored. As part of our India-Leh-Dexamethasone-expedition-2020 (INDEX 2020) programme, we examined the phenotype of control (n = 14) and dexamethasone (n = 13) groups, which were airlifted from Delhi (∼225 m elevation) to Leh, Ladakh (∼3,500 m), India, for 3 days. Dexamethasone 4 mg twice daily significantly attenuated the rise in blood pressure, heart rate, pulmonary pressure, and drop in SaO2 resulting from high-altitude exposure compared to control-treated subjects. Of note, the effect of dexamethasone was substantially greater in women than in men, in whom the drug had relatively little effect. Thus, for the first time, this study shows a sex-biased regulation by dexamethasone of physiologic parameters resulting from the hypoxic environment of high-altitude, which impacts the development of high-altitude pulmonary hypertension and acute mountain sickness. Future studies of cellular contributions toward sex-specific regulation may provide further insights and preventive measures in managing sex-specific, high-altitude–related disorders.
Collapse
Affiliation(s)
- Neha Chanana
- Department of Genomics and Molecular Medicine, CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - Tsering Palmo
- Department of Genomics and Molecular Medicine, CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - Kavita Sharma
- Department of Genomics and Molecular Medicine, CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - Rahul Kumar
- Department of Medicine, University of California, San Francisco, San Francisco, CA, United States
| | - Bhushan Shah
- Department of Cardiology, GB Pant Institute of Post Graduate Medical Education and Research, New Delhi, India
| | - Sudhanshu Mahajan
- Department of Cardiology, GB Pant Institute of Post Graduate Medical Education and Research, New Delhi, India
| | - Girish M. Palleda
- Department of Cardiology, GB Pant Institute of Post Graduate Medical Education and Research, New Delhi, India
| | - Mohit D. Gupta
- Department of Cardiology, GB Pant Institute of Post Graduate Medical Education and Research, New Delhi, India
| | - Ritushree Kukreti
- Department of Genomics and Molecular Medicine, CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - Mohammad Faruq
- Department of Genomics and Molecular Medicine, CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - Tashi Thinlas
- Department of Medicine, Sonam Norboo Memorial Hospital, Leh, Ladakh, India
| | - Brian B. Graham
- Department of Medicine, University of California, San Francisco, San Francisco, CA, United States
| | - Qadar Pasha
- Department of Genomics and Molecular Medicine, CSIR-Institute of Genomics and Integrative Biology, Delhi, India
- Institute of Hypoxia Research, New Delhi, India
- *Correspondence: Qadar Pasha,
| |
Collapse
|
9
|
Richalet J, Hermand E. Modeling the oxygen transport to the myocardium at maximal exercise at high altitude. Physiol Rep 2022; 10:e15262. [PMID: 35439356 PMCID: PMC9017981 DOI: 10.14814/phy2.15262] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 03/22/2022] [Accepted: 03/23/2022] [Indexed: 06/14/2023] Open
Abstract
Exposure to high altitude induces a decrease in oxygen pressure and saturation in the arterial blood, which is aggravated by exercise. Heart rate (HR) at maximal exercise decreases when altitude increases in prolonged exposure to hypoxia. We developed a simple model of myocardial oxygenation in order to demonstrate that the observed blunting of maximal HR at high altitude is necessary for the maintenance of a normal myocardial oxygenation. Using data from the available scientific literature, we estimated the myocardial venous oxygen pressure and saturation at maximal exercise in two conditions: (1) with actual values of maximal HR (decreasing with altitude); (2) with sea-level values of maximal heart rate, whatever the altitude (no change in HR). We demonstrated that, in the absence of autoregulation of maximal HR, myocardial tissue oxygenation would be incompatible with life above 6200 m-7600 m, depending on the hypothesis concerning a possible increase in coronary reserve (increase in coronary blood flow at exercise). The decrease in maximal HR at high altitude could be explained by several biological mechanisms involving the autonomic nervous system and its receptors on myocytes. These experimental and clinical observations support the hypothesis that there exists an integrated system at the cellular level, which protects the myocardium from a hazardous disequilibrium between O2 supply and O2 consumption at high altitude.
Collapse
Affiliation(s)
- Jean‐Paul Richalet
- UMR INSERM U1272 Hypoxie & PoumonUniversité Sorbonne Paris NordBobignyFrance
| | - Eric Hermand
- Université Littoral Côte d’OpaleUniversité ArtoisUniversité Lille, CHU LilleULR 7369 ‐ URePSSS‐Unité de Recherche Pluridisciplinaire Sport Santé SociétéDunkerqueFrance
| |
Collapse
|
10
|
Treml B, Wallner B, Blank C, Fries D, Schobersberger W. The Influence of Environmental Hypoxia on Hemostasis—A Systematic Review. Front Cardiovasc Med 2022; 9:813550. [PMID: 35252392 PMCID: PMC8894865 DOI: 10.3389/fcvm.2022.813550] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 01/24/2022] [Indexed: 12/26/2022] Open
Abstract
Humans have been ascending to high altitudes for centuries, with a growing number of professional- and leisure-related sojourns occurring in this millennium. A multitude of scientific reports on hemostatic disorders at high altitude suggest that hypoxia is an independent risk factor. However, no systematic analysis of the influence of environmental hypoxia on coagulation, fibrinolysis and platelet function has been performed. To fill this gap, we performed a systematic literature review, including only the data of healthy persons obtained during altitude exposure (<60 days). The results were stratified by the degree of hypoxia and sub-categorized into active and passive ascents and sojourns. Twenty-one studies including 501 participants were included in the final analysis. Since only one study provided relevant data, no conclusions regarding moderate altitudes (1,500–2,500 m) could be drawn. At high altitude (2,500–5,400 m), only small pathophysiological changes were seen, with a possible impact of increasing exercise loads. Elevated thrombin generation seems to be balanced by decreased platelet activation. Viscoelastic methods do not support increased thrombogenicity, with fibrinolysis being unaffected by high altitude. At extreme altitude (5,400–8,850 m), the limited data showed activation of coagulation in parallel with stimulation of fibrinolysis. Furthermore, multiple confounding variables at altitude, like training status, exercise load, fluid status and mental stress, prevent definitive conclusions being drawn on the impact of hypoxia on hemostasis. Thus, we cannot support the hypothesis that hypoxia triggers hypercoagulability and increases the risk of thromboembolic disorders, at least in healthy sojourners.
Collapse
Affiliation(s)
- Benedikt Treml
- General and Surgical Intensive Care Medicine, Department of Anesthesiology and Critical Care Medicine, Medical University Innsbruck, Innsbruck, Austria
| | - Bernd Wallner
- Department of Anesthesiology and Critical Care Medicine, Medical University Innsbruck, Innsbruck, Austria
- *Correspondence: Bernd Wallner
| | - Cornelia Blank
- Institute for Sports Medicine, Alpine Medicine and Health Tourism, Private University for Health Sciences, Medical Informatics and Technology UMIT, Hall i.T. and Tirol Kliniken GmbH, University Hospital Innsbruck, Innsbruck, Austria
| | - Dietmar Fries
- General and Surgical Intensive Care Medicine, Department of Anesthesiology and Critical Care Medicine, Medical University Innsbruck, Innsbruck, Austria
| | - Wolfgang Schobersberger
- Institute for Sports Medicine, Alpine Medicine and Health Tourism, Private University for Health Sciences, Medical Informatics and Technology UMIT, Hall i.T. and Tirol Kliniken GmbH, University Hospital Innsbruck, Innsbruck, Austria
| |
Collapse
|
11
|
Falla M, Papagno C, Dal Cappello T, Vögele A, Hüfner K, Kim J, Weiss EM, Weber B, Palma M, Mrakic-Sposta S, Brugger H, Strapazzon G. A Prospective Evaluation of the Acute Effects of High Altitude on Cognitive and Physiological Functions in Lowlanders. Front Physiol 2021; 12:670278. [PMID: 33995130 PMCID: PMC8113692 DOI: 10.3389/fphys.2021.670278] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 04/06/2021] [Indexed: 11/13/2022] Open
Abstract
Cognitive function impairment due to high altitude exposure has been reported with some contradictory results regarding the possible selective cognitive domain involvement. We prospectively evaluated in 36 lowlanders, exposed for 3 consecutive days to an altitude of 3,269 m, specific cognitive abilities (attention, processing speed, and decision-making) required to safely explore the mountains, as well as to work at altitude. We simultaneously monitored the physiological parameters. Our study provides evidence of a reduced processing speed in lowlanders when exposed to altitude in the first 24 h. There was a fairly quick recovery since this impairment was no more detectable after 36 h of exposure. There were no clinically relevant effects on decision-making, while psychomotor vigilance was unaffected at altitude except for individuals with poor sleep. Significant changes were seen in physiological parameters (increased heart rate and reduced peripheral oxygen saturation). Our results may have practical implications, suggesting that individuals should practice prudence with higher ascent when performing risky activities in the first 24–36 h, even at altitudes below 3,500 m, due to an impairment of the cognitive performance that could worsen and lead to accidents.
Collapse
Affiliation(s)
- Marika Falla
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy.,Center for Mind/Brain Sciences CIMeC, University of Trento, Rovereto, Italy
| | - Costanza Papagno
- Center for Mind/Brain Sciences CIMeC, University of Trento, Rovereto, Italy.,Department of Psychology, University of Milano-Bicocca, Milan, Italy
| | - Tomas Dal Cappello
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Anna Vögele
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Katharina Hüfner
- Department of Psychiatry, Psychotherapy and Psychosomatics, Division of Psychiatry II, Medical University of Innsbruck, Innsbruck, Austria
| | - Jenny Kim
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Dallas, TX, United States
| | - Elisabeth M Weiss
- Department of Psychology, University of Innsbruck, Innsbruck, Austria
| | - Bernhard Weber
- Department of Psychology, University of Graz, Graz, Austria
| | - Martin Palma
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | | | - Hermann Brugger
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Giacomo Strapazzon
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| |
Collapse
|
12
|
Richalet JP. [Adaption to chronic hypoxaemia by populations living at high altitude]. Rev Mal Respir 2021; 38:395-403. [PMID: 33541755 DOI: 10.1016/j.rmr.2020.11.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 10/13/2020] [Indexed: 12/14/2022]
Abstract
Permanent life at high altitude induces important physiological stresses linked to the exposure to chronic hypoxia. Various strategies have been adopted by diverse populations living in the Andes, Tibet or East Africa. The main mechanism is an increase in red blood cell production, more marked in Andeans than in Tibetans or Ethiopians. Other changes are observed in the cardiovascular or respiratory systems, as well as in the utero-placental circulation. Sometimes, a de-adaptation process to hypoxia develops, when erythrocytosis becomes excessive and leads to haematological, vascular and cerebral complications (Monge's disease or chronic mountain sickness). Pulmonary hypertension may also appear. Therapeutic options are available but not sufficiently used. Genetic studies have recently been undertaken to try to better understand the evolution of the human genome in populations living in various high altitude regions of the world, as well as the genetic risk factors for chronic diseases. A new model has appeared, intermittent chronic hypoxia, due to the development of economic activities (mainly mining) in desert regions of the Altiplano.
Collapse
Affiliation(s)
- J-P Richalet
- Laboratoire « Hypoxie & Poumon », UMR Inserm U1272, Université Sorbonne Paris Nord 13, 74, rue Marcel-Cachin, 93017 Bobigny cedex, France.
| |
Collapse
|
13
|
Chanana N, Palmo T, Newman JH, Pasha MAQ. Vascular homeostasis at high-altitude: role of genetic variants and transcription factors. Pulm Circ 2020; 10:2045894020913475. [PMID: 33282179 PMCID: PMC7682230 DOI: 10.1177/2045894020913475] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 02/14/2020] [Indexed: 12/24/2022] Open
Abstract
High-altitude pulmonary edema occurs most frequently in non-acclimatized low landers on exposure to altitude ≥2500 m. High-altitude pulmonary edema is a complex condition that involves perturbation of signaling pathways in vasoconstrictors, vasodilators, anti-diuretics, and vascular growth factors. Genetic variations are instrumental in regulating these pathways and evidence is accumulating for a role of epigenetic modification in hypoxic responses. This review focuses on the crosstalk between high-altitude pulmonary edema-associated genetic variants and transcription factors, comparing high-altitude adapted and high-altitude pulmonary edema-afflicted subjects. This approach might ultimately yield biomarker information both to understand and to design therapies for high-altitude adaptation.
Collapse
Affiliation(s)
- Neha Chanana
- Genomics and Molecular Medicine, CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - Tsering Palmo
- Genomics and Molecular Medicine, CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - John H Newman
- Pulmonary Circulation Center, Division of Allergy, Pulmonary and Critical Care Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - M A Qadar Pasha
- Genomics and Molecular Medicine, CSIR-Institute of Genomics and Integrative Biology, Delhi, India.,Indian Council of Medical Research, New Delhi, India
| |
Collapse
|
14
|
Medina-Lezama J, Herrera-Enriquez K, Narvaez-Guerra O, Chirinos JA. Influence of altitude on hypertension phenotypes and responses to antihypertensive therapy: Review of the literature and design of the INTERVENCION trial. J Clin Hypertens (Greenwich) 2020; 22:1757-1762. [PMID: 32941700 DOI: 10.1111/jch.13932] [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: 03/17/2020] [Revised: 05/18/2020] [Accepted: 05/26/2020] [Indexed: 11/29/2022]
Abstract
Systemic arterial hypertension constitutes the leading cause of mortality worldwide, and affects people living at different altitudes above sea level (AASL). AASL has a major impact on cardiovascular function and various biologic pathways that regulate blood pressure-related phenotypes, but whether it affects the clinical response to antihypertensive therapy is unknown. The hemodynamic adaptations observed among lowlanders acutely exposed to high altitude (HA) is distinct from those observed among HA dwellers. However, the phenotypic patterns of hypertension and the response to standard antihypertensive agents among adults chronically exposed to different AASL are poorly understood. The authors describe the protocol for the INTERVENCION trial, a randomized clinical trial designed to assess the effects of three first-line antihypertensive monotherapies (a thiazide diuretic, an angiotensin receptor blocker, and a calcium channel blocker) on peripheral and central blood pressure, in-office blood pressure, and ambulatory blood pressure hemodynamics of hypertensive patients living at different AASL (low altitude, intermediate altitude, and high altitude). The primary end point is the reduction in 24-hour brachial systolic blood pressure. The INTERVENCION trial will provide the first clinical trial data regarding the influence of AASL on the response to antihypertensive monotherapy, as well as the hemodynamic characteristics of arterial hypertension at different AASL.
Collapse
Affiliation(s)
- Josefina Medina-Lezama
- PREVENCION Research Institute, Santa Maria Catholic University School of Medicine, Arequipa, Peru
| | - Karela Herrera-Enriquez
- PREVENCION Research Institute, Santa Maria Catholic University School of Medicine, Arequipa, Peru.,Department of Internal Medicine, Sinai Hospital of Baltimore, Baltimore, Maryland, USA
| | - Offdan Narvaez-Guerra
- PREVENCION Research Institute, Santa Maria Catholic University School of Medicine, Arequipa, Peru.,Department of Internal Medicine, University of Connecticut Health Center, Farmington, Connecticut, USA
| | - Julio A Chirinos
- Division of Cardiovascular Medicine, Hospital of the University of Pennsylvania and Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| |
Collapse
|
15
|
De Bels D, Pierrakos C, Bruneteau A, Reul F, Crevecoeur Q, Marrone N, Vissenaeken D, Borgers G, Balestra C, Honoré PM, Theunissen S. Variation of Cognitive Function During a Short Stay at Hypobaric Hypoxia Chamber (Altitude: 3842 M). Front Physiol 2019; 10:806. [PMID: 31316394 PMCID: PMC6611417 DOI: 10.3389/fphys.2019.00806] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 06/06/2019] [Indexed: 12/12/2022] Open
Abstract
Objective To observe the effects of a fast-acute ascent to high altitude on brain cognitive function and transcranial doppler parameters in order to understand the physiological countermeasures of hypoxia. Methods 17 high-altitude-naïve male subjects (mean age was 26.3 ± 8.1 years) participated in the study. We measured Critical Flicker Fusion Frequency (CFFF), blood oxygen saturation, Psychology Experiment Building (PEBL) including three tests (Modified Math Processing Task, Perceptual Vigilance Task, and Time Estimation Task), as well as Cerebral Blood Flow index (CBFi), mean cerebral artery Systolic and diastolic velocities, Cerebral Pulsatility index (CPi), and heart Rate. All were measured at sea level, at least 1 h after arrival at the hypobaric hypoxia equivalent of 3842 m and 1 h after return to sea level. Results Under acute exposure to hypobaric hypoxic conditions, significant decrease in CFFF [42.1 ± 1 vs. 43.5 ± 1.7 Hz at sea level (asl), p < 0.01], CBFi (611 ± 51 vs. 665 ± 71 asl, p < 0.01) and blood oxygen saturation (83 ± 4% vs. 98 ± 1% asl, p < 0.001) as compared to pre-ascent values were observed. Physiological countermeasures to hypoxia could be involved as there was no significant change in neuropsychometric tests, Systolic and Diastolic velocities and CPi. A significant increase in Heart Rate (81 ± 15 bpm vs. 66 ± 15 bpm asl, p < 0.001) was observed. All parameters returned to their basal values 1 h after regaining sea level. Conclusion Hypoxia results in a decrease in CFFF, CBFi and oxygen saturation and in an increase in heart rate. As it decreased, Cerebral Blood Flow index does not seem to be the physiological measurement of choice to hypoxia explaining the maintenance of cognitive performance after acute exposure to hypobaric hypoxia and requires further investigation. Cerebral oxygen delivery and extraction could be one of the underlying mechanisms.
Collapse
Affiliation(s)
- D De Bels
- Department of Intensive Care Medicine, Brugmann University Hospital, Brussels, Belgium.,Unit of Oxygen Study, Translational Research Laboratory, Université Libre de Bruxelles, Brussels, Belgium.,Laboratory of Integrative Physiology, Haute Ecole Bruxelles-Brabant, Brussels, Belgium
| | - C Pierrakos
- Department of Intensive Care Medicine, Brugmann University Hospital, Brussels, Belgium.,Unit of Oxygen Study, Translational Research Laboratory, Université Libre de Bruxelles, Brussels, Belgium
| | - A Bruneteau
- Laboratory of Integrative Physiology, Haute Ecole Bruxelles-Brabant, Brussels, Belgium
| | - F Reul
- Faculty of Medicine, Université catholique de Louvain, Brussels, Belgium
| | - Q Crevecoeur
- Laboratory of Integrative Physiology, Haute Ecole Bruxelles-Brabant, Brussels, Belgium
| | - N Marrone
- Laboratory of Integrative Physiology, Haute Ecole Bruxelles-Brabant, Brussels, Belgium
| | - D Vissenaeken
- Hypobaric Chamber, Queen Astrid Military Hospital, Brussels, Belgium
| | - G Borgers
- Hypobaric Chamber, Queen Astrid Military Hospital, Brussels, Belgium
| | - C Balestra
- Laboratory of Integrative Physiology, Haute Ecole Bruxelles-Brabant, Brussels, Belgium
| | - P M Honoré
- Department of Intensive Care Medicine, Brugmann University Hospital, Brussels, Belgium
| | - S Theunissen
- Laboratory of Integrative Physiology, Haute Ecole Bruxelles-Brabant, Brussels, Belgium
| |
Collapse
|
16
|
Narvaez-Guerra O, Herrera-Enriquez K, Medina-Lezama J, Chirinos JA. Systemic Hypertension at High Altitude. Hypertension 2019; 72:567-578. [PMID: 30354760 DOI: 10.1161/hypertensionaha.118.11140] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Offdan Narvaez-Guerra
- From the Santa María Catholic University and PREVENCION Research Institute, Arequipa, Peru (O.N.-G., K.H.-E., J.M.-L.)
| | - Karela Herrera-Enriquez
- From the Santa María Catholic University and PREVENCION Research Institute, Arequipa, Peru (O.N.-G., K.H.-E., J.M.-L.)
| | - Josefina Medina-Lezama
- From the Santa María Catholic University and PREVENCION Research Institute, Arequipa, Peru (O.N.-G., K.H.-E., J.M.-L.)
| | - Julio A Chirinos
- University of Pennsylvania Perelman School of Medicine and Hospital of the University of Pennsylvania, Philadelphia (J.A.C.)
| |
Collapse
|
17
|
Boos CJ, Vincent E, Mellor A, O'Hara J, Newman C, Cruttenden R, Scott P, Cooke M, Matu J, Woods DR. The Effect of Sex on Heart Rate Variability at High Altitude. Med Sci Sports Exerc 2018; 49:2562-2569. [PMID: 28731986 DOI: 10.1249/mss.0000000000001384] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
There is evidence suggesting that high altitude (HA) exposure leads to a fall in heart rate variability (HRV) that is linked to the development of acute mountain sickness (AMS). The effects of sex on changes in HRV at HA and its relationship to AMS are unknown. METHODS HRV (5-min single-lead ECG) was measured in 63 healthy adults (41 men and 22 women) 18-56 yr of age at sea level (SL) and during a HA trek at 3619, 4600, and 5140 m, respectively. The main effects of altitude (SL, 3619 m, 4600 m, and 5140 m) and sex (men vs women) and their potential interaction were assessed using a factorial repeated-measures ANOVA. Logistic regression analyses were performed to assess the ability of HRV to predict AMS. RESULTS Men and women were of similar age (31.2 ± 9.3 vs 31.7 ± 7.5 yr), ethnicity, and body and mass index. There was main effect for altitude on heart rate, SD of normal-to-normal (NN) intervals (SDNN), root mean square of successive differences (RMSSD), number of pairs of successive NN differing by >50 ms (NN50), NN50/total number of NN, very low-frequency power, low-frequency (LF) power, high-frequency (HF) power, and total power (TP). The most consistent effect on post hoc analysis was reduction in these HRV measures between 3619 and 5140 m at HA. Heart rate was significantly lower and SDNN, RMSSD, LF power, HF power, and TP were higher in men compared with women at HA. There was no interaction between sex and altitude for any of the HRV indices measured. HRV was not predictive of AMS development. CONCLUSIONS Increasing HA leads to a reduction in HRV. Significant differences between men and women emerge at HA. HRV was not predictive of AMS.
Collapse
Affiliation(s)
- Christopher John Boos
- 1Department of Cardiology, Poole Hospital NHS Foundation trust, Poole, UNITED KINGDOM; 2Department of Postgraduate Medical Education, Bournemouth University, Bournemouth, UNITED KINGDOM; 3Research Institute for Sport, Physical Activity and Leisure, Leeds Beckett University, Leeds, UNITED KINGDOM; 4Defence Medical Services, Lichfield, UNITED KINGDOM; 5Department of Anaesthetics, James Cook University Hospital, Middlesbrough, UNITED KINGDOM; 6Department of Medicine, Northumbria and Newcastle NHS Trusts, Wansbeck General and Royal Victoria Infirmary, Newcastle, UNITED KINGDOM; and 7Department of Academic Medicine, University of Newcastle, Newcastle upon Tyne, UNITED KINGDOM
| | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Machuki J, Zhang H, Harding S, Sun H. Molecular pathways of oestrogen receptors and β-adrenergic receptors in cardiac cells: Recognition of their similarities, interactions and therapeutic value. Acta Physiol (Oxf) 2018; 222. [PMID: 28994249 PMCID: PMC5813217 DOI: 10.1111/apha.12978] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 09/07/2017] [Accepted: 10/02/2017] [Indexed: 12/18/2022]
Abstract
Oestrogen receptors (ERs) and β-adrenergic receptors (βARs) play important roles in the cardiovascular system. Moreover, these receptors are expressed in cardiac myocytes and vascular tissues. Numerous experimental observations support the hypothesis that similarities and interactions exist between the signalling pathways of ERs (ERα, ERβ and GPR30) and βARs (β1 AR, β2 AR and β3 AR). The recently discovered oestrogen receptor GPR30 shares structural features with the βARs, and this forms the basis for the interactions and functional overlap. GPR30 possesses protein kinase A (PKA) phosphorylation sites and PDZ binding motifs and interacts with A-kinase anchoring protein 5 (AKAP5), all of which enable its interaction with the βAR pathways. The interactions between ERs and βARs occur downstream of the G-protein-coupled receptor, through the Gαs and Gαi proteins. This review presents an up-to-date description of ERs and βARs and demonstrates functional synergism and interactions among these receptors in cardiac cells. We explore their signalling cascades and the mechanisms that orchestrate their interactions and propose new perspectives on the signalling patterns for the GPR30 based on its structural resemblance to the βARs. In addition, we explore the relevance of these interactions to cell physiology, drugs (especially β-blockers and calcium channel blockers) and cardioprotection. Furthermore, a receptor-independent mechanism for oestrogen and its influence on the expression of βARs and calcium-handling proteins are discussed. Finally, we highlight promising therapeutic avenues that can be derived from the shared pathways, especially the phosphatidylinositol-3-OH kinase (PI3K/Akt) pathway.
Collapse
Affiliation(s)
- J.O. Machuki
- Department of Physiology; Xuzhou Medical University; Xuzhou China
| | - H.Y. Zhang
- Department of Physiology; Xuzhou Medical University; Xuzhou China
| | - S.E. Harding
- National Heart and Lung Institute; Imperial College; London UK
| | - H. Sun
- Department of Physiology; Xuzhou Medical University; Xuzhou China
| |
Collapse
|
19
|
Abstract
INTRODUCTION The autonomic system and sympathetic activation appears integral in the pathogenesis of acute mountain sickness (AMS) at high altitude (HA), yet a link between heart rate variability (HRV) and AMS has not been convincingly shown. In this study we investigated the utility of the smartphone-derived HRV score to predict and diagnose AMS at HA. METHODS Twenty-one healthy adults were investigated at baseline at 1400 m and over 10 days during a trek to 5140 m. HRV was recorded using the ithlete HRV device. RESULTS Acute mountain sickness occurred in 11 subjects (52.4%) at >2650 m. HRV inversely correlated with AMS Scores (r = -0.26; 95% CI, -0.38 to -0.13: P < 0.001). HRV significantly fell at 3700, 4100, and 5140 m versus low altitude. HRV scores were lower in those with both mild (69.7 ± 14.0) and severe AMS (67.1 ± 13.1) versus those without AMS (77.5 ± 13.1; effect size n = 0.043: P = 0.007). The HRV score was weakly predictive of severe AMS (AUC 0.74; 95% CI, 0.58-0.89: P = 0.006). The change (delta) in the HRV Score (compared with baseline at 1400 m) was a moderate diagnostic marker of severe AMS (AUC 0.80; 95% CI, 0.70-0.90; P = 0.0004). A fall in the HRV score of >5 had a sensitivity of 83% and specificity of 60% to identify severe AMS (likelihood ratio 1.9). Baseline HRV at 1400 m was not predictive of either AMS at higher altitudes. CONCLUSIONS The ithlete HRV score can be used to help in the identification of severe AMS; however, a baseline score is not predictive of future AMS development at HA.
Collapse
|
20
|
Strewe C, Zeller R, Feuerecker M, Hoerl M, Kumprej I, Crispin A, Johannes B, Debevec T, Mekjavic I, Schelling G, Choukèr A. PlanHab study: assessment of psycho-neuroendocrine function in male subjects during 21 d of normobaric hypoxia and bed rest. Stress 2017; 20:131-139. [PMID: 28166699 DOI: 10.1080/10253890.2017.1292246] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Immobilization and hypoxemia are conditions often seen in patients suffering from severe heart insufficiency or primary pulmonary diseases (e.g. fibrosis, emphysema). In future planned long-duration and exploration class space missions (including habitats on the moon and Mars), healthy individuals will encounter such a combination of reduced physical activity and oxygen tension by way of technical reasons and the reduced gravitational forces. These overall unconventional extraterrestrial conditions can result in yet unknown consequences for the regulation of stress-permissive, psycho-neuroendocrine responses, which warrant appropriate measures in order to mitigate foreseeable risks. The Planetary Habitat Simulation Study (PlanHab) investigated these two space-related conditions: bed rest as model of reduced gravity and normobaric hypoxia, with the aim of examining their influence on psycho-neuroendocrine responses. We hypothesized that both conditions independently increase measures of psychological stress and enhance neuroendocrine markers of stress, and that these effects would be exacerbated by combined treatment. The cross-over study composed of three interventions (NBR, normobaric normoxic horizontal bed rest; HBR, normobaric hypoxic horizontal bed rest; HAMB, normobaric hypoxic ambulatory confinement) with 14 male subjects during three sequential campaigns separated by 4 months. The psychological state was determined through three questionnaires and principal neuroendocrine responses were evaluated by measuring cortisol in saliva, catecholamine in urine, and endocannabinoids in blood. The results revealed no effects after 3 weeks of normobaric hypoxia on psycho-neuroendocrine responses. Conversely, bed rest induced neuroendocrine alterations that were not influenced by hypoxia.
Collapse
Affiliation(s)
- C Strewe
- a Department of Anaesthesiology , Klinikum Großhadern, University of Munich, Stress and Immunology Lab , Munich , Germany
| | - R Zeller
- a Department of Anaesthesiology , Klinikum Großhadern, University of Munich, Stress and Immunology Lab , Munich , Germany
| | - M Feuerecker
- a Department of Anaesthesiology , Klinikum Großhadern, University of Munich, Stress and Immunology Lab , Munich , Germany
| | - M Hoerl
- a Department of Anaesthesiology , Klinikum Großhadern, University of Munich, Stress and Immunology Lab , Munich , Germany
| | - I Kumprej
- a Department of Anaesthesiology , Klinikum Großhadern, University of Munich, Stress and Immunology Lab , Munich , Germany
- b Department of Automation, Biocybernetics and Robotics , Jozef Stefan Institute , Ljubljana , Slovenia
| | - A Crispin
- c Department of Biometry and Epidemiology, Klinikum Großhadern , University of Munich , Munich , Germany
| | - B Johannes
- d Department of Space Physiology , Institute of Aerospace Medicine, German Aerospace Center (DLR) , Cologne , Germany
| | - T Debevec
- b Department of Automation, Biocybernetics and Robotics , Jozef Stefan Institute , Ljubljana , Slovenia
| | - I Mekjavic
- b Department of Automation, Biocybernetics and Robotics , Jozef Stefan Institute , Ljubljana , Slovenia
| | - G Schelling
- a Department of Anaesthesiology , Klinikum Großhadern, University of Munich, Stress and Immunology Lab , Munich , Germany
| | - A Choukèr
- a Department of Anaesthesiology , Klinikum Großhadern, University of Munich, Stress and Immunology Lab , Munich , Germany
| |
Collapse
|