1
|
Yang M, Raviskanthan S, Mortensen PW, Garg T, Lee AG. Transient Bilateral Visual Loss as the Presenting Symptom of High-Altitude Ascent-Related Cytotoxic Lesion of the Corpus Callosum. J Neuroophthalmol 2023; 43:e268-e270. [PMID: 35234680 DOI: 10.1097/wno.0000000000001449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Matthew Yang
- Department of Ophthalmology (MT, AGL), University of Texas Medical Branch, Galveston, Texas; Department of Ophthalmology (SR, PWM, AGL), Blanton Eye Institute, Houston Methodist Hospital, Houston, Texas; Department of Neurology (TG), Houston Methodist Hospital, Houston, Texas; Departments of Ophthalmology, Neurology, and Neurosurgery (AGL), Weill Cornell Medicine, New York, New York; Department of Ophthalmology (AGL), University of Texas MD Anderson Cancer Center, Houston, Texas; Texas A and M College of Medicine (AGL), Bryan, Texas; and Department of Ophthalmology (AGL), The University of Iowa Hospitals and Clinics, Iowa City, Iowa
| | | | | | | | | |
Collapse
|
2
|
Li Y, Li C, Luo T, Yue T, Xiao W, Yang L, Zhang Z, Han F, Long P, Hu Y. Progress in the Treatment of High Altitude Cerebral Edema: Targeting REDOX Homeostasis. J Inflamm Res 2023; 16:2645-2660. [PMID: 37383357 PMCID: PMC10296571 DOI: 10.2147/jir.s415695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 06/15/2023] [Indexed: 06/30/2023] Open
Abstract
With the increasing of altitude activities from low-altitude people, the study of high altitude cerebral edema (HACE) has been revived. HACE is a severe acute mountain sickness associated with exposure to hypobaric hypoxia at high altitude, often characterized by disturbance of consciousness and ataxia. As for the pathogenesis of HACE, previous studies suggested that it might be related to the disorder of cerebral blood flow, the destruction of blood-brain barrier and the injury of brain parenchyma cells caused by inflammatory factors. In recent years, studies have confirmed that the imbalance of REDOX homeostasis is also involved in the pathogenesis of HACE, which mainly leads to abnormal activation of microglia and destruction of tight junction of vascular endothelial cells through the excessive production of mitochondrial-related reactive oxygen species. Therefore, this review summarizes the role of REDOX homeostasis and the potential of the treatment of REDOX homeostasis in HACE, which is of great significance to expand the understanding of the pathogenesis of HACE. Moreover, it will also be helpful to further study the possible therapy of HACE related to the key link of REDOX homeostasis.
Collapse
Affiliation(s)
- Yubo Li
- School of Clinical Medicine, Chengdu University of TCM, Chengdu, People’s Republic of China
- Basic Medical Laboratory, The General Hospital of Western Theater Command, Chengdu, People’s Republic of China
| | - Chengming Li
- School of Clinical Medicine, Chengdu University of TCM, Chengdu, People’s Republic of China
- Basic Medical Laboratory, The General Hospital of Western Theater Command, Chengdu, People’s Republic of China
| | - Tao Luo
- Department of Ophthalmology, The General Hospital of Western Theater Command, Chengdu, People’s Republic of China
| | - Tian Yue
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, People’s Republic of China
| | - Wenjing Xiao
- Department of Pharmacy, The General Hospital of Western Theater Command, Chengdu, People’s Republic of China
| | - Ling Yang
- School of Clinical Medicine, Chengdu University of TCM, Chengdu, People’s Republic of China
- Basic Medical Laboratory, The General Hospital of Western Theater Command, Chengdu, People’s Republic of China
| | - Zaiyuan Zhang
- College of Medicine, 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
| | - Pan Long
- Department of Ophthalmology, The General Hospital of Western Theater Command, Chengdu, People’s Republic of China
| | - Yonghe Hu
- College of Medicine, Southwest Jiaotong University, Chengdu, People’s Republic of China
| |
Collapse
|
3
|
Liu YA, Mesentier-Louro LA, Shariati MA, Moss HE, Beres SJ, Liao YJ. High Altitude as a Risk Factor for the Development of Nonarteritic Anterior Ischemic Optic Neuropathy. J Neuroophthalmol 2023; 43:69-75. [PMID: 36166787 PMCID: PMC10870828 DOI: 10.1097/wno.0000000000001629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Episodic high-altitude exposure leads to optic disc edema and retinopathy. It is uncertain whether high-altitude exposure is a risk factor for nonarteritic anterior ischemic optic neuropathy (NAION). METHODS We performed a single-center, retrospective, cross-sectional case study of 5 patients with high-altitude-associated NAION (HA-NAION) from April 2014 to April 2019. Main study parameters included known vascular risk factors for NAION, evolution of visual acuity, visual field, optic disc, and macula measurements. RESULTS We studied 5 eyes of 5 patients with HA-NAION that occurred at 7,000-9,000 ft above sea level, 28 patients with classic NAION that developed at sea level (normal altitude NAION or NA-NAION), and 40 controls. All 5 patients with HA-NAION had clinically confirmed NAION by a neuro-ophthalmologist within 3-21 days of onset and comprehensive follow-up evaluations (average follow-up of 23 months). Other than high-altitude exposure, 4 of 5 patients had undiagnosed obstructive sleep apnea (OSA, apnea-hypopnea index 5.4-22.2) and 1 had systemic vascular risk factors. All patients had disc-at-risk in the contralateral eye. The best-corrected distance visual acuity was 20/20 to 20/70 (median logMAR 0) at presentation and 20/70 to counting finger (median logMAR 0) at ≥6 months. Automated static perimetry revealed average mean deviation of -18.6 dB at presentation and -22.1 dB at ≥6 months. The average retinal nerve fiber layer was 244 µm (80-348 µm) at onset and 59 µm (55-80 µm) at ≥6 months. The average ganglion cell complex thickness was 50 µm (43-54 µm) at onset and 52 µm (50-55 µm) at ≥6 months. The patients with OSA were started on home continuous positive airway pressure treatment. Visual outcomes were similar in patients with HA-NAION and NA-NAION. - After addressing all NAION risk factors, no new events occurred in the HA-NAION group within 2-8 years with or without repeat high-altitude exposure. CONCLUSIONS NAION can occur under high-altitude conditions. HA-NAION is associated with relatively younger age at onset, disc-at-risk, and OSA. These patients exhibit a relatively progressive course of vision loss after initial onset and severe thinning of optic nerves on optical coherence tomography. Treatment for OSA is recommended, especially with repeated high-altitude exposure.
Collapse
Affiliation(s)
- Yin A Liu
- Department of Ophthalmology (YAL, LAM-L, MAS, HEM, SJB, YJL), Stanford University School of Medicine, Stanford, California; Departments of Ophthalmology & Vision Science, Neurology, and Neurological Surgery (YAL), University of California, Davis, Sacramento, California; and Department of Neurology & Neurological Sciences (HEM, SJB, YJL), Stanford University School of Medicine, Stanford, California
| | | | | | | | | | | |
Collapse
|
4
|
Retinal microvasculature is a potential biomarker for acute mountain sickness. SCIENCE CHINA. LIFE SCIENCES 2023:10.1007/s11427-022-2271-x. [PMID: 36811802 DOI: 10.1007/s11427-022-2271-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 12/21/2022] [Indexed: 02/24/2023]
Abstract
Increased cerebral blood flow resulting from altered capillary level autoregulation at high altitudes leads to capillary overperfusion and then vasogenic cerebral edema, which is the leading hypothesis of acute mountain sickness (AMS). However, studies on cerebral blood flow in AMS have been mostly restricted to gross cerebrovascular endpoints as opposed to the microvasculature. This study aimed to investigate ocular microcirculation alterations, the only visualized capillaries in the central neural system (CNS), during early-stage AMS using a hypobaric chamber. This study found that after high altitude simulation, the optic nerve showed retinal nerve fiber layer thickening (P=0.004-0.018) in some locations, and the area of the optic nerve subarachnoid space (P=0.004) enlarged. Optical coherence tomography angiography (OCTA) showed increased retinal radial peripapillary capillary (RPC) flow density (P=0.003-0.046), particularly on the nasal side of the nerve. The AMS-positive group had the largest increases in RPC flow density in the nasal sector (AMS-positive, Δ3.21±2.37; AMS-negative, Δ0.01±2.16, P=0.004). Among multiple ocular changes, OCTA increase in RPC flow density was associated with simulated early-stage AMS symptoms (beta=0.222, 95%CI, 0.009-0.435, P=0.042). The area under the receiver operating characteristics curve (AUC) for the changes in RPC flow density to predict early-stage AMS outcomes was 0.882 (95%CI, 0.746-0.998). The results further confirmed that overperfusion of microvascular beds is the key pathophysiologic change in early-stage AMS. RPC OCTA endpoints may serve as a rapid, noninvasive potential biomarker for CNS microvascular changes and AMS development during risk assessment of individuals at high altitudes.
Collapse
|
5
|
Mlinar T, Debevec T, Kapus J, Najdenov P, McDonnell AC, Ušaj A, Mekjavic IB, Jaki Mekjavic P. Retinal blood vessel diameters in children and adults exposed to a simulated altitude of 3,000 m. Front Physiol 2023; 14:1026987. [PMID: 36926190 PMCID: PMC10011172 DOI: 10.3389/fphys.2023.1026987] [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: 08/24/2022] [Accepted: 02/14/2023] [Indexed: 03/08/2023] Open
Abstract
Introduction: Technological advances have made high-altitude ski slopes easily accessible to skiers of all ages. However, research on the effects of hypoxia experienced during excursions to such altitudes on physiological systems, including the ocular system, in children is scarce. Retinal vessels are embryologically of the same origin as vessels in the brain, and have similar anatomical and physiological characteristics. Thus, any hypoxia-related changes in the morphology of the former may reflect the status of the latter. Objective: To compare the effect of one-day hypoxic exposure, equivalent to the elevation of high-altitude ski resorts in North America and Europe (∼3,000 m), on retinal vessel diameter between adults and children. Methods: 11 adults (age: 40.1 ± 4.1 years) and 8 children (age: 9.3 ± 1.3 years) took part in the study. They spent 3 days at the Olympic Sports Centre Planica (Slovenia; altitude: 940 m). During days 1 and 2 they were exposed to normoxia (FiO2 = 0.209), and day 3 to normobaric hypoxia (FiO2 = 0.162 ± 0.03). Digital high-resolution retinal fundus photographs were obtained in normoxia (Day 2) and hypoxia (Day 3). Central retinal arteriolar equivalent (CRAE) and venular equivalents (CRVE) were determined using an Automated Retinal Image Analyser. Results: Central retinal arteriolar and venular equivalents increased with hypoxia in children (central retinal arteriolar equivalent: 105.32 ± 7.72 µm, hypoxia: 110.13 ± 7.16 µm, central retinal venular equivalent: normoxia: 123.39 ± 8.34 µm, hypoxia: 130.11 ± 8.54 µm) and adults (central retinal arteriolar equivalent: normoxia: 105.35 ± 10.67 µm, hypoxia: 110.77 ± 8.36 µm; central retinal venular equivalent: normoxia: 126.89 ± 7.24 µm, hypoxia: 132.03 ± 9.72 µm), with no main effect of group or group*condition interaction. A main effect of condition on central retinal arteriolar and venular equivalents was observed (central retinal arteriolar equivalent:normoxia: 105.34 ± 9.30 µm, hypoxia: 110.50 ± 7.67 µm, p < 0.001; central retinal venular equivalent: normoxia: 125.41 ± 7.70 µm, hypoxia: 131.22 ± 9.05 µm, p < 0.001). Conclusion: A 20-hour hypoxic exposure significantly increased central retinal arteriolar and venular equivalents in adults and children. These hypoxia-induced increases were not significantly different between the age groups, confirming that vasomotor sensitivity of the retinal vessels to acute hypoxia is comparable between adults and prepubertal children.
Collapse
Affiliation(s)
- Tinkara Mlinar
- Department of Automatics, Biocybernetics and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia.,Jozef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Tadej Debevec
- Department of Automatics, Biocybernetics and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia.,Faculty of Sport, University of Ljubljana, Ljubljana, Slovenia
| | - Jernej Kapus
- Faculty of Sport, University of Ljubljana, Ljubljana, Slovenia
| | - Peter Najdenov
- Department of Paediatrics, General Hospital Jesenice, Jesenice, Slovenia
| | - Adam C McDonnell
- Department of Automatics, Biocybernetics and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia
| | - Anton Ušaj
- Faculty of Sport, University of Ljubljana, Ljubljana, Slovenia
| | - Igor B Mekjavic
- Department of Automatics, Biocybernetics and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia.,Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC, Canada
| | - Polona Jaki Mekjavic
- Department of Automatics, Biocybernetics and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia.,Eye Hospital, University Medical Centre, Ljubljana, Slovenia.,Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| |
Collapse
|
6
|
Shi Z, Jiang X, Geng Y, Yue X, Gao J, Cheng X, Zhao M, Zhu L. Expression profile of cytokines and chemokines in a mouse high-altitude cerebral edema model. Int J Immunopathol Pharmacol 2023; 37:3946320231177189. [PMID: 37188519 DOI: 10.1177/03946320231177189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023] Open
Abstract
INTRODUCTION High-altitude cerebral edema (HACE) is considered to be the end-stage of acute mountain sickness (AMS); however, its pathophysiological mechanism remains unknown. Increasing evidences support that inflammation is an important risk factor for the occurrence of HACE. Including our published papers, previous studies demonstrated that the levels of IL-6, IL-1β, and TNF-α in both serum and hippocampus were increased in the mouse HACE model induced by LPS stimulation combined with hypobaric hypoxia exposure; however, the expression profile of other cytokines and chemokines remains unknown. OBJECTIVE This study was to analyze the expression profile of cytokines and chemokines in the HACE model. METHODS The mouse HACE model was established by LPS stimulation combined with hypobaric hypoxia exposure (LH). The mice were divided into the normoxic group, LH-6 h group, LH-1 d group, and LH-7 d group. Brain water content (BWC) was determined using the wet/dry weight ratio. The levels of 30 cytokines and chemokines in the serum and hippocampal tissue were detected using LiquiChip. The mRNA expression of cytokines and chemokines in hippocampal tissue were determined by q-PCR. RESULTS In the current study, we found that the brain water content was increased after the combinational treatment of LPS and hypobaric hypoxia. The results of LiquiChip showed that, in the serum and hippocampal tissue, most factors in all 30 cytokines and chemokines were dramatically upregulated at 6 h, and then declined at the 1st d and 7th d. Among these factors, G-CSF, M-CSF, MCP-1, KC, MIG, Eotaxin, Rantes, IP10, IL-6, MIP-2, and MIP-1β were all increased in both serum and hippocampal tissue at 6 h. In addition, the results of q-PCR showed the mRNA levels of G-CSF, MCP-1, KC, MIG, Eotaxin, Rantes, IP10, IL-6, MIP-2, and MIP-1β in hippocampal tissue were dramatically upregulated at 6 h. CONCLUSION This study showed that the dynamic expression profile of 30 cytokines and chemokines in a mouse HACE model induced by LPS plus hypobaric hypoxia. The levels of G-CSF, MCP-1, KC, MIG, Eotaxin, Rantes, IP10, IL-6, MIP-2, and MIP-1β in both serum and hippocampus were significantly increased at 6 h, which may be involved in the occurrence and development of HACE.
Collapse
Affiliation(s)
- Zibi Shi
- Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Xiufang Jiang
- Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Yanan Geng
- Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Xiangpei Yue
- Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Jiayue Gao
- Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Xiang Cheng
- Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Ming Zhao
- Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Lingling Zhu
- Beijing Institute of Basic Medical Sciences, Beijing, China
- Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
- School of Pharmaceutical Sciences, University of South China, Hengyang, China
| |
Collapse
|
7
|
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.
Collapse
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,
| |
Collapse
|
8
|
Follis F, Martucci G, Arcadipane A, Follis M, Rajbanshi B, Lorusso R. Resuscitation for moribund alpinists stranded at high altitudes: A stepwise approach including ECMO as a last resort strategy. Artif Organs 2022; 46:1459-1462. [PMID: 35643844 DOI: 10.1111/aor.14320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 04/28/2022] [Accepted: 05/16/2022] [Indexed: 11/30/2022]
Affiliation(s)
- Fabrizio Follis
- Department of Cardiac Surgery, Istituto di Ricerca e Cura a Carattere Scientifico-Istituto Mediterraneo per i Trapianti e Terapie ad Alta Specializzazione (IRCCS-ISMETT), Palermo, Italy
| | - Gennaro Martucci
- Department of Anesthesia and Intensive Care, Istituto di Ricerca e Cura a Carattere Scientifico-Istituto Mediterraneo per i Trapianti e Terapie ad Alta Specializzazione (IRCCS-ISMETT), Palermo, Italy
| | - Antonio Arcadipane
- Department of Anesthesia and Intensive Care, Istituto di Ricerca e Cura a Carattere Scientifico-Istituto Mediterraneo per i Trapianti e Terapie ad Alta Specializzazione (IRCCS-ISMETT), Palermo, Italy
| | - Marco Follis
- Department of Cardiac Surgery, Klinikum, Braunschweig, Germany
| | - Bijoy Rajbanshi
- Department of Cardiac Surgery, Nepal Mediciti Hospital, Kathmandu, Nepal
| | - Roberto Lorusso
- Department of Cardiothoracic Surgery, Heart and Vascular Centre, Maastricht University Medical Centre, Maastricht, The Netherlands
| |
Collapse
|
9
|
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.
Collapse
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
| |
Collapse
|
10
|
Doutreleau S. [Physiological and pathological responses to altitude]. Rev Mal Respir 2021; 38:1013-1024. [PMID: 34782179 DOI: 10.1016/j.rmr.2020.12.007] [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: 02/10/2020] [Accepted: 12/28/2020] [Indexed: 11/27/2022]
Abstract
Hypobaric hypoxia, the hallmark of a high altitude environment, has important physiological effects on both the cardiovascular and respiratory systems in order to maintain a balance between oxygen demand and supply. This dynamic of acclimatization is influenced both by the level of altitude and the speed of progression, but is also very individual with a wide spectrum of responses and sensitivities. This wide range of responses is associated with nonspecific symptoms characterising acute mountain sickness and high-altitude cerebral or pulmonary oedema. This article reviews the current knowledge about both the acclimatization processes and specific diseases of high-altitude.
Collapse
Affiliation(s)
- S Doutreleau
- Inserm, UM sports et pathologies, laboratoire HP2, CHU Grenoble-Alpes, université Grenoble Alpes, EXALT - centre d'expertise sur l'altitude, 38000 Grenoble, France.
| |
Collapse
|
11
|
Cysteine becomes conditionally essential during hypobaric hypoxia and regulates adaptive neuro-physiological responses through CBS/H 2S pathway. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165769. [PMID: 32184133 DOI: 10.1016/j.bbadis.2020.165769] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 02/02/2020] [Accepted: 03/12/2020] [Indexed: 12/17/2022]
Abstract
Brain is well known for its disproportionate oxygen consumption and high energy-budget for optimal functioning. The decrease in oxygen supply to brain, thus, necessitates rapid activation of adaptive pathways - the absence of which manifest into vivid pathological conditions. Amongst these, oxygen sensing in glio-vascular milieu and H2S-dependent compensatory increase in cerebral blood flow (CBF) is a major adaptive response. We had recently demonstrated that the levels of H2S were significantly decreased during chronic hypobaric hypoxia (HH)-induced neuro-pathological effects. The mechanistic basis of this phenomenon, however, remained to be deciphered. We, here, describe experimental evidence for marked limitation of cysteine during HH - both in animal model as well as human volunteers ascending to high altitude. We show that the preservation of brain cysteine level, employing cysteine pro-drug (N-acetyl-L-cysteine, NAC), markedly curtailed effects of HH - not only on endogenous H2S levels but also, impairment of spatial reference memory in our animal model. We, further, present multiple lines of experimental evidence that the limitation of cysteine was causally governed by physiological propensity of brain to utilize cysteine, in cystathionine beta synthase (CBS)-dependent manner, past its endogenous replenishment potential. Notably, decrease in the levels of brain cysteine manifested despite positive effect (up-regulation) of HH on endogenous cysteine maintenance pathways and thus, qualifying cysteine as a conditionally essential nutrient (CEN) during HH. In brief, our data supports an adaptive, physiological role of CBS-mediated cysteine-utilization pathway - activated to increase endogenous levels of H2S - for optimal responses of brain to hypobaric hypoxia.
Collapse
|
12
|
Krusche T, Limmer M, Jendrusch G, Platen P. Influence of Natural Hypobaric Hypoxic Conditions on Dynamic Visual Performance. High Alt Med Biol 2020; 21:1-11. [PMID: 31746645 DOI: 10.1089/ham.2019.0033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Background: Both dynamic and static visual performances are essential for safety and motoric performance at altitude. There is a lack of information regarding alterations in dynamic visual performance (DVP) in oxygen-reduced environments. The purpose of this study was to analyze DVP in natural hypoxic conditions in a group of young, healthy hikers. Methods: DVP in four parafoveal subfields was analyzed using the computer-assisted Düsseldorf Test for Dynamic Vision. Measurements were performed twice at altitudes above 3500 m during an 8-day alpine hike. Results: On day 5 (3647 m), no changes in DVP were detected. On day 6 (4554 m), however, we found a significant reduction in DVP in the superior parafoveal retinal subfield, partly representing the lower visual field. The observed changes did not correlate with oxygen saturation, hematocrit, or cardiovascular parameters. We found no interrelation between symptoms of acute mountain sickness and DVP at altitude. Conclusions: Our data suggest that hiking at altitudes above 4500 m results in lower DVP in the visual field of healthy young people. The alteration might affect motor performance and coordination, increasing the risk of accidents.
Collapse
Affiliation(s)
- Till Krusche
- Department of Sports Medicine and Sports Nutrition, Faculty of Sport Science, Ruhr-Universität Bochum, Bochum, Germany
| | - Mirjam Limmer
- Department of Sports Medicine and Sports Nutrition, Faculty of Sport Science, Ruhr-Universität Bochum, Bochum, Germany.,Institute of Outdoor Sports and Environmental Science, German Sport University Cologne, Cologne, Germany
| | - Gernot Jendrusch
- Department of Sports Medicine and Sports Nutrition, Faculty of Sport Science, Ruhr-Universität Bochum, Bochum, Germany
| | - Petra Platen
- Department of Sports Medicine and Sports Nutrition, Faculty of Sport Science, Ruhr-Universität Bochum, Bochum, Germany
| |
Collapse
|
13
|
DING Y, LI W, WANG R, ZHANG J. [Research progress on the effects of plateau hypoxia on blood-brain barrier structure and drug permeability]. Zhejiang Da Xue Xue Bao Yi Xue Ban 2019; 48:668-673. [PMID: 31955542 PMCID: PMC8800771 DOI: 10.3785/j.issn.1008-9292.2019.12.12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 10/03/2019] [Indexed: 06/10/2023]
Abstract
Drugs for the treatment of central nervous system diseases need to enter the brain tissue through the blood-brain barrier to function. In high altitude hypoxic environment, there are changes in tight junction proteins of blood-brain barrier tissue structure, transporters in astrocytes and endothelial cells and ATP in endothelial cells; at the same time the permeability of the blood-brain barrier is increased. These changes are an important reference for rational drug use in patients with central nervous system disease in the plateau region. This article reviews the research progress on the effects of plateau hypoxia on the structure of the blood-brain barrier and related drug permeability.
Collapse
Affiliation(s)
| | | | - Rong WANG
- 王荣(1969-), 男, 博士, 主任药师, 教授, 博士生导师, 主要从事高原药代动力学等研究, E-mail:
;
https://orcid.org/0000-0001-9139-7311
| | - Jianchun ZHANG
- 张建春(1968-), 女, 博士, 硕士生导师, 主任药师, 主要从事药物新剂型及中药制剂研究, E-mail:
;
https://orcid.org/0000-0001-9459-8995
| |
Collapse
|
14
|
Clarke AK, Cozzi M, Imray CHE, Wright A, Pagliarini S. Analysis of Retinal Segmentation Changes at High Altitude With and Without Acetazolamide. Invest Ophthalmol Vis Sci 2019; 60:36-40. [PMID: 30601929 DOI: 10.1167/iovs.18-24966] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Our aim was to assess retinal venous diameter and segmented retinal layer thickness variation in acute systemic hypoxia with and without acetazolamide and to relate these changes to high altitude headache (HAH), as a proxy for intracerebral pathophysiology. Methods A total of 20 subjects participated in a 4-day ascent to the Margherita Hut (4,559 m) on Monte Rosa in the Italian Alps. Each participant was randomized to either oral acetazolamide 250 mg twice daily or placebo. A combination of digital imaging and optical coherence tomography was used to measure retinal vessel diameter and retinal layer thickness. Clinically-assessed HAH was recorded. Results A total of 18 participants had usable digital and OCT images, with 12 developing HAH. Significant thickening was seen only in the two inner layers of the retina, the retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) at P = 0.012 and P = 0.010, respectively, independent of acetazolamide. There was a significant positive correlation between HAH and both retinal venous diameter (T = 4.953, P = 0.001) and retinal artery diameter (T = 2.865, P = 0.015), with both unaffected by acetazolamide (F = 0.439, P = 0.518). Conclusions Retinal venous diameter correlates positively with HAH, adding further evidence for the proposed venous outflow limitation mechanism. The inner layers of the retina swelled disproportionately when compared to the outer layers under conditions of systemic hypoxia. Acetazolamide does not appear to influence altitudinal changes of retinal layers and vasculature.
Collapse
Affiliation(s)
| | - Mariano Cozzi
- University Hospitals Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
| | | | - Alex Wright
- College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Sergio Pagliarini
- University Hospitals Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
| | | |
Collapse
|
15
|
Krusche T, Jendrusch G, Platen P. Short- and middle-term high-altitude exposure does not affect visual acuity and contrast sensitivity of healthy young people. J Sci Med Sport 2019; 22 Suppl 1:S12-S16. [PMID: 31151876 DOI: 10.1016/j.jsams.2019.04.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 04/23/2019] [Accepted: 04/30/2019] [Indexed: 10/26/2022]
Abstract
OBJECTIVE Visual acuity and contrast sensitivity are crucial for optimal performance and safe sport activity. From a practical sport-specific perspective, visual performance is obligatory for orientation and movement control in mountainous areas. The purpose of this study was to analyze the effect of hypobaric hypoxic conditions on visual acuity and contrast sensitivity of short-term and middle-term acclimatized healthy young people. DESIGN This study used a repeated-measure design with ten eye-healthy and physically active students representing different types of sports. METHODS With the help of a computer-based Landolt C and a Sine Wave Contrast test, visual performance was investigated similar before (156 m), during a nine-day high-altitude sojourn (sleeping level: 890-4640 m), and three months later (156 m). All tests were performed under standardized illumination conditions. Additionally, morning blood oxygen saturation, hematocrits, hemoglobin, body mass, and self-reported symptoms of acute mountain sickness criteria were determined. RESULTS Whole blood oxygen saturation declined during altitude exposure. The analysis of central visual performance at altitude showed no effect of hypobaric hypoxia. CONCLUSION Our data suggest that activity in a hypobaric hypoxia condition at moderate to high altitude levels of up to 4600 m does not affect visual acuity and contrast sensitivity of acclimatized healthy young people. However, in contrast to previous studies that outlined acutely impaired central visual performance with respect to hypoxia, we suggest that acclimatization might induce adaptation of visual perception performance and therefore reduce the risk of accidents resulting from partial loss of visual performance at altitude.
Collapse
Affiliation(s)
- Till Krusche
- Department of Sports Medicine and Sports Nutrition, Faculty of Sport Science, Ruhr-Universität Bochum, Germany.
| | - Gernot Jendrusch
- Department of Sports Medicine and Sports Nutrition, Faculty of Sport Science, Ruhr-Universität Bochum, Germany
| | - Petra Platen
- Department of Sports Medicine and Sports Nutrition, Faculty of Sport Science, Ruhr-Universität Bochum, Germany
| |
Collapse
|
16
|
Inada M, Taguchi M, Harimoto K, Karasawa Y, Takeuchi M, Ito M. Protective effects of dexamethasone on hypoxia-induced retinal edema in a mouse model. Exp Eye Res 2019; 178:82-90. [DOI: 10.1016/j.exer.2018.09.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 09/09/2018] [Accepted: 09/25/2018] [Indexed: 01/09/2023]
|
17
|
Joyce K, Lucas S, Imray C, Balanos G, Wright AD. Advances in the available non-biological pharmacotherapy prevention and treatment of acute mountain sickness and high altitude cerebral and pulmonary oedema. Expert Opin Pharmacother 2018; 19:1891-1902. [DOI: 10.1080/14656566.2018.1528228] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- K.E. Joyce
- School of Sport, Exercise, & Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - S.J.E. Lucas
- School of Sport, Exercise, & Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - C.H.E. Imray
- Department of Vascular Surgery, University Hospitals of Coventry and Warwickshire; Warwick Medical School, Coventry, UK
| | - G.M Balanos
- School of Sport, Exercise, & Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - A. D. Wright
- Department of Medicine, University of Birmingham, Edgbaston, UK
| |
Collapse
|
18
|
Hüfner K, Brugger H, Kuster E, Dünsser F, Stawinoga AE, Turner R, Tomazin I, Sperner-Unterweger B. Isolated psychosis during exposure to very high and extreme altitude - characterisation of a new medical entity. Psychol Med 2018; 48:1872-1879. [PMID: 29202898 PMCID: PMC6088769 DOI: 10.1017/s0033291717003397] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 10/24/2017] [Accepted: 10/24/2017] [Indexed: 12/27/2022]
Abstract
BACKGROUND Psychotic episodes during exposure to very high or extreme altitude have been frequently reported in mountain literature, but not systematically analysed and acknowledged as a distinct clinical entity. METHODS Episodes reported above 3500 m altitude with possible psychosis were collected from the lay literature and provide the basis for this observational study. Dimensional criteria of the Diagnostic and Statistical Manual of Mental Disorders were used for psychosis, and the Lake Louise Scoring criteria for acute mountain sickness and high-altitude cerebral oedema (HACE). Eighty-three of the episodes collected underwent a cluster analysis to identify similar groups. Ratings were done by two independent, trained researchers (κ values 0.6-1).FindingsCluster 1 included 51% (42/83) episodes without psychosis; cluster 2 22% (18/83) cases with psychosis, plus symptoms of HACE or mental status change from other origins; and cluster 3 28% (23/83) episodes with isolated psychosis. Possible risk factors of psychosis and associated somatic symptoms were analysed between the three clusters and revealed differences regarding the factors 'starvation' (χ2 test, p = 0.002), 'frostbite' (p = 0.024) and 'supplemental oxygen' (p = 0.046). Episodes with psychosis were reversible but associated with near accidents and accidents (p = 0.007, odds ratio 4.44). CONCLUSIONS Episodes of psychosis during exposure to high altitude are frequently reported, but have not been specifically examined or assigned to medical diagnoses. In addition to the risk of suffering from somatic mountain illnesses, climbers and workers at high altitude should be aware of the potential occurrence of psychotic episodes, the associated risks and respective coping strategies.
Collapse
Affiliation(s)
- Katharina Hüfner
- Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital of Psychiatry II, Medical University Innsbruck, Innsbruck, Austria
| | - Hermann Brugger
- Institute of Mountain Emergency Medicine, EURAC research, Bolzano, Italy
- Medical University Innsbruck, Innsbruck, Austria
| | - Eva Kuster
- Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital of Psychiatry II, Medical University Innsbruck, Innsbruck, Austria
| | - Franziska Dünsser
- Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital of Psychiatry II, Medical University Innsbruck, Innsbruck, Austria
| | | | - Rachel Turner
- Institute of Mountain Emergency Medicine, EURAC research, Bolzano, Italy
- Medical University Innsbruck, Innsbruck, Austria
| | - Iztok Tomazin
- Department of Family Medicine, Faculty of Medicine, University of Ljubljana, Slovenia
| | - Barbara Sperner-Unterweger
- Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital of Psychiatry II, Medical University Innsbruck, Innsbruck, Austria
| |
Collapse
|
19
|
Roach RC, Hackett PH, Oelz O, Bärtsch P, Luks AM, MacInnis MJ, Baillie JK. The 2018 Lake Louise Acute Mountain Sickness Score. High Alt Med Biol 2018; 19:4-6. [PMID: 29583031 DOI: 10.1089/ham.2017.0164] [Citation(s) in RCA: 276] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Roach, Robert C., Peter H. Hackett, Oswald Oelz, Peter Bärtsch, Andrew M. Luks, Martin J. MacInnis, J. Kenneth Baillie, and The Lake Louise AMS Score Consensus Committee. The 2018 Lake Louise Acute Mountain Sickness Score. High Alt Med Biol 19:1-4, 2018.- The Lake Louise Acute Mountain Sickness (AMS) scoring system has been a useful research tool since first published in 1991. Recent studies have shown that disturbed sleep at altitude, one of the five symptoms scored for AMS, is more likely due to altitude hypoxia per se, and is not closely related to AMS. To address this issue, and also to evaluate the Lake Louise AMS score in light of decades of experience, experts in high altitude research undertook to revise the score. We here present an international consensus statement resulting from online discussions and meetings at the International Society of Mountain Medicine World Congress in Bolzano, Italy, in May 2014 and at the International Hypoxia Symposium in Lake Louise, Canada, in February 2015. The consensus group has revised the score to eliminate disturbed sleep as a questionnaire item, and has updated instructions for use of the score.
Collapse
Affiliation(s)
- Robert C Roach
- 1 Altitude Research Center, Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado School of Medicine , Anschutz Medical Campus, Aurora, Colorado
| | - Peter H Hackett
- 1 Altitude Research Center, Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado School of Medicine , Anschutz Medical Campus, Aurora, Colorado
| | - Oswald Oelz
- 2 Department of Internal Medicine, University of Zurich , Switzerland
| | - Peter Bärtsch
- 3 Department of Internal Medicine, University Hospital , Heidelberg, Germany
| | - Andrew M Luks
- 4 Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Washington , Seattle, WA
| | | | - J Kenneth Baillie
- 6 Roslin Institute, University of Edinburgh , Easter Bush, Midlothian, United Kingdom .,7 Intensive Care Unit, Royal Infirmary Edinburgh, Edinburgh, United Kingdom
| | | |
Collapse
|
20
|
Muza SR. Wearable physiological sensors and real-time algorithms for detection of acute mountain sickness. J Appl Physiol (1985) 2018; 124:557-563. [DOI: 10.1152/japplphysiol.00367.2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
This is a minireview of potential wearable physiological sensors and algorithms (process and equations) for detection of acute mountain sickness (AMS). Given the emerging status of this effort, the focus of the review is on the current clinical assessment of AMS, known risk factors (environmental, demographic, and physiological), and current understanding of AMS pathophysiology. Studies that have examined a range of physiological variables to develop AMS prediction and/or detection algorithms are reviewed to provide insight and potential technological roadmaps for future development of real-time physiological sensors and algorithms to detect AMS. Given the lack of signs and nonspecific symptoms associated with AMS, development of wearable physiological sensors and embedded algorithms to predict in the near term or detect established AMS will be challenging. Prior work using [Formula: see text], HR, or HRv has not provided the sensitivity and specificity for useful application to predict or detect AMS. Rather than using spot checks as most prior studies have, wearable systems that continuously measure SpO2 and HR are commercially available. Employing other statistical modeling approaches such as general linear and logistic mixed models or time series analysis to these continuously measured variables is the most promising approach for developing algorithms that are sensitive and specific for physiological prediction or detection of AMS.
Collapse
Affiliation(s)
- Stephen R. Muza
- Strategic Science Management Office, US Army Research Institute of Environmental Medicine, Natick, Massachusetts
| |
Collapse
|
21
|
Tian X, Zhang B, Jia Y, Wang C, Li Q. Retinal changes following rapid ascent to a high-altitude environment. Eye (Lond) 2018; 32:370-374. [PMID: 28912514 PMCID: PMC5811714 DOI: 10.1038/eye.2017.195] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 07/26/2017] [Indexed: 01/26/2023] Open
Abstract
PurposeTo determine what impact rapid ascension to a high-altitude environment has on the retina with the aim of preventing and treating high-altitude oculopathy.Patients and methodsParticipants in the study were members of the Chinese military assigned to the high-altitude environment of the Tibetan plateau. Ninety-one participants were enrolled in the study. Optical coherence tomography was used to measure the thickness of retina-related indicators. Measurements were taken before and after exposure to the high-altitude environment and upon return to the baseline altitude.ResultsFollowing exposure to the high-altitude environment in Tibet, there was a significant increase in retinal nerve fiber layer (RNFL) thickness in the temporal and nasal quadrants of the optic disc, whilst a significant decrease in RNFL thickness in the inferior optic disc was also observed. A significant increase in RNFL thickness in the superior and inferior macula was also evident, along with a significant increase in the ganglion cell layer thickness in the superior macula. Upon return to the baseline altitude, all measurements returned to baseline levels except for the RNFL of the inferior macula, which was significantly thicker. Pathological changes were also documented in the eyes of nine participants upon returning to baseline altitude, including ischemic optic neuropathy, myopia, and cortical amaurosis.ConclusionsThe high-altitude environment can have a negative impact on the health of the retina and may contribute to the incidence of various eye diseases. This study deepens the understanding of what impact a high-altitude environment has on retina and provides reliable data for blindness prevention and treatment.
Collapse
Affiliation(s)
- X Tian
- Department of Ophthalmology, the 153rd Central Hospital of PLA, Zhengzhou, China
| | - B Zhang
- Department of Ophthalmology, the 153rd Central Hospital of PLA, Zhengzhou, China
| | - Y Jia
- Department of Ophthalmology, the 153rd Central Hospital of PLA, Zhengzhou, China
| | - C Wang
- Department of Ophthalmology, the 153rd Central Hospital of PLA, Zhengzhou, China
| | - Q Li
- Department of Ophthalmology, the 153rd Central Hospital of PLA, Zhengzhou, China
| |
Collapse
|
22
|
McLaughlin CW, Skabelund AJ, George AD. Impact of High Altitude on Military Operations. CURRENT PULMONOLOGY REPORTS 2017. [DOI: 10.1007/s13665-017-0181-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|
23
|
Luks AM, Swenson ER, Bärtsch P. Acute high-altitude sickness. Eur Respir Rev 2017; 26:26/143/160096. [PMID: 28143879 PMCID: PMC9488514 DOI: 10.1183/16000617.0096-2016] [Citation(s) in RCA: 224] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 10/23/2016] [Indexed: 12/28/2022] Open
Abstract
At any point 1–5 days following ascent to altitudes ≥2500 m, individuals are at risk of developing one of three forms of acute altitude illness: acute mountain sickness, a syndrome of nonspecific symptoms including headache, lassitude, dizziness and nausea; high-altitude cerebral oedema, a potentially fatal illness characterised by ataxia, decreased consciousness and characteristic changes on magnetic resonance imaging; and high-altitude pulmonary oedema, a noncardiogenic form of pulmonary oedema resulting from excessive hypoxic pulmonary vasoconstriction which can be fatal if not recognised and treated promptly. This review provides detailed information about each of these important clinical entities. After reviewing the clinical features, epidemiology and current understanding of the pathophysiology of each disorder, we describe the current pharmacological and nonpharmacological approaches to the prevention and treatment of these diseases. Lack of acclimatisation is the main risk factor for acute altitude illness; descent is the optimal treatmenthttp://ow.ly/45d2305JyZ0
Collapse
Affiliation(s)
- Andrew M Luks
- Dept of Medicine, Division of Pulmonary and Critical Care Medicine, University of Washington, Seattle, WA, USA
| | - Erik R Swenson
- Dept of Medicine, Division of Pulmonary and Critical Care Medicine, University of Washington, Seattle, WA, USA.,Medical Service, Veterans Affairs Puget Sound Health Care System, Seattle, WA, USA
| | - Peter Bärtsch
- Dept of Internal Medicine, University Clinic Heidelberg, Heidelberg, Germany
| |
Collapse
|
24
|
Kumar G, Chhabra A, Mishra S, Kalam H, Kumar D, Meena R, Ahmad Y, Bhargava K, Prasad DN, Sharma M. H2S Regulates Hypobaric Hypoxia-Induced Early Glio-Vascular Dysfunction and Neuro-Pathophysiological Effects. EBioMedicine 2016; 6:171-189. [PMID: 27211559 PMCID: PMC4856789 DOI: 10.1016/j.ebiom.2016.03.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 02/29/2016] [Accepted: 03/01/2016] [Indexed: 12/20/2022] Open
Abstract
Hypobaric Hypoxia (HH) is an established risk factor for various neuro-physiological perturbations including cognitive impairment. The origin and mechanistic basis of such responses however remain elusive. We here combined systems level analysis with classical neuro-physiological approaches, in a rat model system, to understand pathological responses of brain to HH. Unbiased ‘statistical co-expression networks’ generated utilizing temporal, differential transcriptome signatures of hippocampus—centrally involved in regulating cognition—implicated perturbation of Glio-Vascular homeostasis during early responses to HH, with concurrent modulation of vasomodulatory, hemostatic and proteolytic processes. Further, multiple lines of experimental evidence from ultra-structural, immuno-histological, substrate-zymography and barrier function studies unambiguously supported this proposition. Interestingly, we show a significant lowering of H2S levels in the brain, under chronic HH conditions. This phenomenon functionally impacted hypoxia-induced modulation of cerebral blood flow (hypoxic autoregulation) besides perturbing the strength of functional hyperemia responses. The augmentation of H2S levels, during HH conditions, remarkably preserved Glio-Vascular homeostasis and key neuro-physiological functions (cerebral blood flow, functional hyperemia and spatial memory) besides curtailing HH-induced neuronal apoptosis in hippocampus. Our data thus revealed causal role of H2S during HH-induced early Glio-Vascular dysfunction and consequent cognitive impairment. Glio-Vascular dysfunction temporally precedes Hypobaric Hypoxia (HH) induced neuro-pathological effects. Exposure to HH significantly lowers the levels of H2S in brain. Augmentation of H2S, utilizing its donor, preserves Glio-Vascular homeostasis and curtails HH-induced memory impairment.
The exposure to Hypobaric Hypoxia (HH) environment (such as that encountered by humans at high altitude) culminates in cognitive impairment in an altitude- and duration-dependent manner. The mechanistic basis for such effects, however, remains elusive. Our present study showed that HH-induced neuro-pathological perturbations are temporally preceded by Glio-Vascular dysfunction and are concomitant with lowered levels of gaseous messenger, H2S, in brain. The maintenance of H2S levels (utilizing a specific donor, NaHS) during hypoxia curtailed HH-induced brain-vascular dysfunction and ensuing neuro-pathological effects (on spatial memory). Interestingly, identification of origin of disease in the present study effectively revealed a possible interventional strategy.
Collapse
Affiliation(s)
- Gaurav Kumar
- Neurobiology Division, Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Delhi 110054, India
| | - Aastha Chhabra
- Peptide and Proteomics Division, Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Delhi 110054, India
| | - Shalini Mishra
- Peptide and Proteomics Division, Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Delhi 110054, India
| | - Haroon Kalam
- Immunology Group, International Center for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi-110067, India
| | - Dhiraj Kumar
- Immunology Group, International Center for Genetic Engineering and Biotechnology (ICGEB), Aruna Asaf Ali Marg, New Delhi-110067, India
| | - Ramniwas Meena
- Peptide and Proteomics Division, Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Delhi 110054, India
| | - Yasmin Ahmad
- Peptide and Proteomics Division, Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Delhi 110054, India
| | - Kalpana Bhargava
- Peptide and Proteomics Division, Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Delhi 110054, India
| | - Dipti N Prasad
- Neurobiology Division, Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Delhi 110054, India
| | - Manish Sharma
- Peptide and Proteomics Division, Defence Institute of Physiology and Allied Sciences (DIPAS), DRDO, Delhi 110054, India.
| |
Collapse
|
25
|
Bruno RM, Ghiadoni L, Pratali L. Vascular adaptation to extreme conditions: The role of hypoxia. Artery Res 2016. [DOI: 10.1016/j.artres.2016.02.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
|
26
|
Riech S, Kallenberg K, Moerer O, Hellen P, Bärtsch P, Quintel M, Knauth M. The Pattern of Brain Microhemorrhages After Severe Lung Failure Resembles the One Seen in High-Altitude Cerebral Edema. Crit Care Med 2015; 43:e386-9. [PMID: 26110491 DOI: 10.1097/ccm.0000000000001150] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES After suffering from severe acute respiratory distress syndrome, several patients show generalized brain alterations and atrophy. A distinctive morphologic pattern of cerebral injury, however, has not been found so far. DATA SOURCES We present the history of three patients who survived severe acute respiratory distress syndrome. In these patients, MRI of the brain showed multiple microhemorrhages predominantly in the splenium of the corpus callosum. An identical pattern of microhemorrhages has previously been described in mountaineers who suffered from high-altitude cerebral edema. CONCLUSIONS This report demonstrates that patients after treatment for acute respiratory distress syndrome and high-altitude cerebral edema show congruent cerebral injuries. Further investigation into the similarities of the causative conditions and neurologic consequences might reveal underlying pathophysiologic mechanisms and clinical implications of this observation.
Collapse
Affiliation(s)
- Sebastian Riech
- 1Department of Anesthesiology, Emergency and Intensive Care Medicine, University Medical Center Göttingen, Göttingen, Germany. 2Department of Diagnostic and Interventional Neuroradiology, University Medical Center Göttingen, Göttingen, Germany. 3Division of Sports Medicine, Department of Internal Medicine, Medical Clinic, University Hospital Heidelberg, Heidelberg, Germany
| | | | | | | | | | | | | |
Collapse
|
27
|
Abstract
The retinal venous pressure (RVP) can be measured non-invasively. While RVP is equal to or slightly above intraocular pressure (IOP) in healthy people, it is often markedly increased in patients with eye or systemic diseases. Beside a mechanical obstruction, the main cause of such an elevation is a local dysregulation of a retinal vein, particularly a constriction induced by endothelin-1 (ET-1). A local increase of ET-1 can result from a high plasma level, as ET-1 can diffuse from the fenestrated capillaries of the choroid into the optic nerve head (ONH), bypassing the blood retinal barrier. A local increase can also result from increased local production either by a sick neighboring artery or retinal tissue. Generally, the main factors increasing ET-1 are inflammations and hypoxia, either locally or in a remote organ. RVP is known to be increased in patients with glaucoma, retinal vein occlusion (RVO), diabetic retinopathy, high mountain disease, and primary vascular dysregulation (PVD). PVD is the major vascular component of Flammer syndrome (FS). An increase of RVP decreases perfusion pressure, which heightens the risk for hypoxia. An increase of RVP also elevates transmural pressure, which in turn heightens the risk for retinal edema. In patients with RVO, a high level of RVP may not only be a consequence but also a potential cause of the occlusion; therefore, it risks causing a vicious circle. Narrow retinal arteries and particularly dilated retinal veins are known risk indicators for future cardiovascular events. As the major cause for such a retinal venous dilatation is an increased RVP, RVP may likely turn out to be an even stronger predictor.
Collapse
Affiliation(s)
- Josef Flammer
- Department of Ophthalmology, University of Basel, Mittlere Strasse 91, CH-4031 Basel, Switzerland
| | - Katarzyna Konieczka
- Department of Ophthalmology, University of Basel, Mittlere Strasse 91, CH-4031 Basel, Switzerland
| |
Collapse
|
28
|
Abstract
Dull and hypoxic brains have been a frequent subject in the medical and mountaineering literature. Deterioration of cognitive and other neurological function occurs at high altitude, with or without high altitude cerebral edema. This historical essay explores a 2014 first-ever English translation of cerebral blood flow studies by nineteenth century physiologist Angelo Mosso. Some of the medical history and physiology of brain function is discussed, but much of the style focuses on quotations from the writings of mountaineers and mountaineering physicians to provide color commentary about dull brains at high altitude.
Collapse
|
29
|
Lochner P, Falla M, Brigo F, Pohl M, Strapazzon G. Ultrasonography of the Optic Nerve Sheath Diameter for Diagnosis and Monitoring of Acute Mountain Sickness: A Systematic Review. High Alt Med Biol 2015; 16:195-203. [DOI: 10.1089/ham.2014.1127] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Affiliation(s)
- Piergiorgio Lochner
- Department of Neurology, General Hospital of Merano, Merano, Italy
- Department of Neurology, University A. Avogadro, Novara, Italy
| | - Marika Falla
- Department of Neurology and Psychiatry, Sapienza University, Roma, Italy
- Department of Neurology, General Hospital of Bolzano, Bolzano, Italy
| | - Francesco Brigo
- Department of Neurology, General Hospital of Merano, Merano, Italy
- Department of Neurological and Movement Sciences, University of Verona, Italy
| | - Michael Pohl
- EURAC Institute of Mountain Emergency Medicine, Bolzano, Italy
- Landeskrankenhaus Bregenz, Austria
| | | |
Collapse
|
30
|
Berger MM, Macholz F, Mairbäurl H, Bärtsch P. Remote ischemic preconditioning for prevention of high-altitude diseases: fact or fiction? J Appl Physiol (1985) 2015; 119:1143-51. [PMID: 26089545 DOI: 10.1152/japplphysiol.00156.2015] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 06/17/2015] [Indexed: 01/14/2023] Open
Abstract
Preconditioning refers to exposure to brief episodes of potentially adverse stimuli and protects against injury during subsequent exposures. This was first described in the heart, where episodes of ischemia/reperfusion render the myocardium resistant to subsequent ischemic injury, which is likely caused by reactive oxygen species (ROS) and proinflammatory processes. Protection of the heart was also found when preconditioning was performed in an organ different from the target, which is called remote ischemic preconditioning (RIPC). The mechanisms causing protection seem to include stimulation of nitric oxide (NO) synthase, increase in antioxidant enzymes, and downregulation of proinflammatory cytokines. These pathways are also thought to play a role in high-altitude diseases: high-altitude pulmonary edema (HAPE) is associated with decreased bioavailability of NO and increased generation of ROS, whereas mechanisms causing acute mountain sickness (AMS) and high-altitude cerebral edema (HACE) seem to involve cytotoxic effects by ROS and inflammation. Based on these apparent similarities between ischemic damage and AMS, HACE, and HAPE, it is reasonable to assume that RIPC might be protective and improve altitude tolerance. In studies addressing high-altitude/hypoxia tolerance, RIPC has been shown to decrease pulmonary arterial systolic pressure in normobaric hypoxia (13% O2) and at high altitude (4,342 m). Our own results indicate that RIPC transiently decreases the severity of AMS at 12% O2. Thus preliminary studies show some benefit, but clearly, further experiments to establish the efficacy and potential mechanism of RIPC are needed.
Collapse
Affiliation(s)
- Marc Moritz Berger
- Department of Anesthesiology, Perioperative and General Critical Care Medicine, Salzburg General Hospital, Paracelsus Medical University, Salzburg, Austria; Department of Anesthesiology, University of Heidelberg, Heidelberg, Germany;
| | - Franziska Macholz
- Department of Anesthesiology, Perioperative and General Critical Care Medicine, Salzburg General Hospital, Paracelsus Medical University, Salzburg, Austria
| | - Heimo Mairbäurl
- Department of Internal Medicine VII, Division of Sports Medicine, University of Heidelberg, Heidelberg, Germany; and Translational Lung Research Center Heidelberg, German Center for Lung Research, Heidelberg, Germany
| | - Peter Bärtsch
- Department of Internal Medicine VII, Division of Sports Medicine, University of Heidelberg, Heidelberg, Germany; and
| |
Collapse
|
31
|
Kayser B. The International Hypoxia Symposium 2015 in Lake Louise: A Report. High Alt Med Biol 2015; 16:261-6. [PMID: 25955961 DOI: 10.1089/ham.2015.0046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Bengt Kayser
- Institute of Sports Sciences of the University of Lausanne and Department of Physiology of the Faculty of Biology and Medicine , Lausanne, Switzerland
| |
Collapse
|
32
|
Berger MM, Köhne H, Hotz L, Hammer M, Schommer K, Bärtsch P, Mairbäurl H. Remote ischemic preconditioning delays the onset of acute mountain sickness in normobaric hypoxia. Physiol Rep 2015; 3:3/3/e12325. [PMID: 25742960 PMCID: PMC4393159 DOI: 10.14814/phy2.12325] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Acute mountain sickness (AMS) is a neurological disorder occurring when ascending too fast, too high. Remote ischemic preconditioning (RIPC) is a noninvasive intervention protecting remote organs from subsequent hypoxic damage. We hypothesized that RIPC protects against AMS and that this effect is related to reduced oxidative stress. Fourteen subjects were exposed to 18 hours of normoxia (21% oxygen) and 18 h of normobaric hypoxia (12% oxygen, equivalent to 4500 m) on different days in a blinded, randomized order. RIPC consisted of four cycles of lower limb ischemia (5 min) and 5 min of reperfusion, and was performed immediately before the study room was entered. A control group was exposed to hypoxia (12% oxygen, n = 14) without RIPC. AMS was evaluated by the Lake Louise score (LLS) and the AMS-C score of the Environmental Symptom Questionnaire. Plasma concentrations of ascorbate radicals, oxidized sulfhydryl (SH) groups, and electron paramagnetic resonance (EPR) signal intensity were measured as biomarkers of oxidative stress. RIPC reduced AMS scores (LLS: 1.9 ± 0.4 vs. 3.2 ± 0.5; AMS-C score: 0.4 ± 0.1 vs. 0.8 ± 0.2), ascorbate radicals (27 ± 7 vs. 65 ± 18 nmol/L), oxidized SH groups (3.9 ± 1.4 vs. 14.3 ± 4.6 μmol/L), and EPR signal intensity (0.6 ± 0.2 vs. 1.5 ± 0.4 × 10(6)) after 5 h in hypoxia (all P < 0.05). After 18 hours in hypoxia there was no difference in AMS and oxidative stress between RIPC and control. AMS and plasma markers of oxidative stress did not correlate. This study demonstrates that RIPC transiently reduces symptoms of AMS and that this effect is not associated with reduced plasma levels of reactive oxygen species.
Collapse
Affiliation(s)
- Marc M Berger
- Department of Anesthesiology, University of Heidelberg, Heidelberg, Germany Department of Anesthesiology, Perioperative and General Critical Care Medicine, Salzburg General Hospital Paracelsus Medical University, Salzburg, Austria
| | - Hannah Köhne
- Department of Anesthesiology, University of Heidelberg, Heidelberg, Germany
| | - Lorenz Hotz
- Department of Anesthesiology, University of Heidelberg, Heidelberg, Germany Department of Anesthesiology, Perioperative and General Critical Care Medicine, Salzburg General Hospital Paracelsus Medical University, Salzburg, Austria
| | - Moritz Hammer
- Department of Internal Medicine VII, Division of Sports Medicine, University of Heidelberg, Heidelberg, Germany
| | - Kai Schommer
- Department of Internal Medicine VII, Division of Sports Medicine, University of Heidelberg, Heidelberg, Germany
| | - Peter Bärtsch
- Department of Internal Medicine VII, Division of Sports Medicine, University of Heidelberg, Heidelberg, Germany
| | - Heimo Mairbäurl
- Department of Internal Medicine VII, Division of Sports Medicine, University of Heidelberg, Heidelberg, Germany
| |
Collapse
|