Angiogenic/ Lymphangiogenic factors and adaptation to extreme altitudes during an expedition to the Everest.

International audienceAim: To analyse the correlation between production of angiogenic (Vascular Endothelial Growth Factor A (VEGF-A) and Interleukin 8 (IL-8)) and lymphangiogenic factors (Vascular Endothelial Growth Factor C and D (VEGF-C and D)) and adaptation to high altitude (> 8000 m). Erythropoietin (EPO) served as a positive control. Methods: We analysed the percentage of oxygen saturation and the plasmatic contents of VEGF-A, C, D, IL-8 and EPO in seven mountaineers and four sherpas during an expedition to Mount Everest. Acute mountain sickness was also evaluated using the Lake Louise score. Results: Whereas VEGF-A, IL-8, VEGF-C and EPO were transiently up-regulated at 5000 m and decreased at the highest altitudes, VEGF-D remained elevated throughout the ascent. Sherpas had increased basal levels of VEGF-A, C, IL-8 and EPO and up-regulation of all the tested factors when they passed the altitude at which they lived. Conclusion: Our data suggest that expression of angiogenic and lymphangiogenic factors is up-regulated directly or indirectly by altitude-dependent hypoxia. Both factors could be involved in a mechanism of adaptation to high altitudes