Effects of high-altitude exposure on vascular endothelial growth factor levels in man

2001 ◽  
Vol 85 (1-2) ◽  
pp. 113-117 ◽  
Author(s):  
Roland Walter ◽  
Marco Maggiorini ◽  
Urs Scherrer ◽  
John Contesse ◽  
Walter H. Reinhart
2020 ◽  
Author(s):  
Yunden Droma ◽  
Takumi Kinjo ◽  
Shuhei Nozawa ◽  
Nobumitsu Kobayashi ◽  
Masanori Yasuo ◽  
...  

AbstractSherpa highlanders demonstrate extraordinary tolerance to hypoxia at high altitudes, partly by one of the adaptation mechanisms promoting increases of microcirculatory blood flow and capillary density at high altitude for restoring oxygen supply to tissues. Hypoxia stimulates vascular endothelial growth factor (VEGF), which is an important signaling protein involved in hypoxia-stimulated vasculogenesis and angiogenesis. Our present study included 51 Sherpas dwelling in Namche Bazaar village (3440 m) and 76 non-Sherpa lowlanders residing in Kathmandu (1300 m) in Nepal. In these participants, we measured plasma VEGF-A concentrations and genotyped five single-nucleotide polymorphisms (SNPs) of VEGFA: rs699947, rs8333061, rs1570360, and rs2010963 in the 5′-untranslated region (5′-UTR); and rs3025039 in the 3′-UTR. The average circulating VEGF-A level in Sherpas did not respond to hypoxia at the high altitude in 3440 m, remaining equivalent to the level in non-Sherpa lowlanders at low altitude. Allele discriminations for the analyzed SNPs revealed significant genetic divergences of rs699947, rs8333061, and rs2010963 in Sherpa highlanders compared with non-Sherpa lowlanders, East Asians, South Asians, and the global population; however, consistency with the indigenous Tibetan highlanders from the Tibet Plateau. On the other hand, the SNP rs3025039 in the 3′-UTR presented constant preserved genetic variation among global populations. Our findings indicated that the physiological sea-level VEGF-A concentration in Sherpa highlanders at high altitude was probably linked with the significant variations of VEGFA in Sherpas that regulate the gene expression in a manner of tolerance to hypoxia through production of the optimal biological level of VEGF-A at high altitudes. Precise angiogenesis at high altitude contributes to the adaptive levels of capillary density and microcirculation, providing efficient and effective diffusion of oxygen to tissues and representing human adaptation to high-altitude hypoxia environment.Author summarySherpa highlanders demonstrate extraordinary tolerance to hypoxia at high altitudes, partly by one of the adaptation mechanisms promoting increases of microcirculatory blood flow and capillary density at high altitude for restoring oxygen supply to tissues. Vascular endothelial growth factor (VEGF) is mainly stimulated by hypoxia, and is an important signaling protein involved in hypoxia-stimulated vasculogenesis and angiogenesis. Interestingly, we found that the circulating VEGF-A level in Sherpa highlanders did not respond to hypoxia at high altitude. Furthermore, allele discrimination of the single nucleotide polymorphisms (SNPs) of VEGFA revealed significant divergences of rs699947, rs8333061, and rs2010963 within the VEGFA regulation region in Sherpa highlanders compared to the non-Sherpa lowlanders, East Asians, South Asians, and the global population; however, consistency with Tibetan highlanders from the Tibet Plateau. We propose that the hypoxia-tolerant circulating VEGF-A level in Sherpa highlanders is linked with the genetic variations of VEGFA, contributing to human adaptation to high-altitude hypoxic environments.


2021 ◽  
Vol 12 ◽  
Author(s):  
Craig Winter ◽  
Tracy Bjorkman ◽  
Stephanie Miller ◽  
Paul Nichols ◽  
John Cardinal ◽  
...  

Purpose: The recognition and treatment of high-altitude illness (HAI) is increasingly important in global emergency medicine. High altitude related hypobaric hypoxia can lead to acute mountain sickness (AMS), which may relate to increased expression of vascular endothelial growth factor (VEGF), and subsequent blood-brain barrier (BBB) compromise. This study aimed to establish the relationship between AMS and changes in plasma VEGF levels during a high-altitude ascent. VEGF level changes with dexamethasone, a commonly used AMS medication, may provide additional insight into AMS.Methods: Twelve healthy volunteers ascended Mt Fuji (3,700 m) and blood samples were obtained at distinct altitudes for VEGF analysis. Oxygen saturation (SPO2) measurements were also documented at the same time-point. Six out of the 12 study participants were prescribed dexamethasone for a second ascent performed 48 h later, and blood was again collected to establish VEGF levels.Results: Four key VEGF observations could be made based on the data collected: (i) the baseline VEGF levels between the two ascents trended upwards; (ii) those deemed to have AMS in the first ascent had increased VEGF levels (23.8–30.3 pg/ml), which decreased otherwise (23.8–30.3 pg/ml); (iii) first ascent AMS participants had higher VEGF level variability for the second ascent, and similar to those not treated with dexamethasone; and (iv) for the second ascent dexamethasone participants had similar VEGF levels to non-AMS first ascent participants, and the variability was lower than for first ascent AMS and non-dexamethasone participants. SPO2 changes were unremarkable, other than reducing by around 5% irrespective of whether measurement was taken for the first or second ascent.Conclusion: First ascent findings suggest a hallmark of AMS could be elevated VEGF levels. The lack of an exercise-induced VEGF level change strengthened the notion that elevated plasma VEGF was brain-derived, and related to AMS.


2007 ◽  
Vol 30 (3) ◽  
pp. 42
Author(s):  
Vy-Van Le ◽  
Michel White ◽  
Rhian Touyz ◽  
Heather Ross ◽  
Yves Tessier ◽  
...  

Background: Exposure to hypobaric hypoxemia causes acute mountain sickness (AMS) in 40% of subjects acutely exposed to an altitude of 4,000 m. Vascular endothelial growth factor (VEGF) and cytokines appear to play a role in AMS in model systems. The objective of this pilot study was to explore the change in VEGF, the vasodilatory prostacyclin PGI-2, interleukin-6 and thiobarbituric acid reactive substances (TBARS) levels following prolonged exposure to hypobaric hypoxemia on Bolivian Altiplano. The secondary objective was to investigate the relationship between these markers with good versus poor adaptation to high altitude. Methods: The study population consisted of 7 climbers aged 24-64 yr. One cardiac transplant and one kidney transplant recipients participated in this study. Aerobic capacity was assessed on a treadmill using a RAMP protocol with gas exchange analyses. Blood samples were harvested within 48 hr of departure and within 24 hr returning to sea level. Results: Selected biochemisty parameters are presented in the table: *** Table in Full Text PDF. *** Data are mean ±SD. CP= cardiopulmonary. Both cardiac and Tx recipients did not experience AMS. Maximum altitude achieved: ∗6120-6522; †5680; ‡5300 meters. Conclusions: Pulmonary maladaptation to high altitude results in a 2-fold elevated VEGF and PGI-2 without concomitant increase of markers of inflammation or oxidative stress. VEGF does not appear to increase in cerebral maladaptation to high altitude. Further investigations are needed to better understand the role of VEGF and other biomarkers during the process of adaptation or maladaptation to high altitude.


Respirology ◽  
2009 ◽  
Vol 14 (1) ◽  
pp. 46-52 ◽  
Author(s):  
Masayuki HANAOKA ◽  
Yunden DROMA ◽  
Masao OTA ◽  
Michiko ITO ◽  
Yoshihiko KATSUYAMA ◽  
...  

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