Skip to main content
. 2022 Sep 23;122(12):2493–2514. doi: 10.1007/s00421-022-05041-y

Fig. 5.

Fig. 5

Shared signalling pathways between circulating factors and the proteins they upregulate. Vascular endothelial growth factor (VEGF) and insulin-growth factor (IGF-1) both bind to unique membrane receptors (VEGFR1, VGEFR2/3, and IGF-1R) while sharing common signalling pathways within the endothelium, via the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) and activation of Akt, as well as through the mitogen-activated protein kinase pathway MEK1/2–ERK1/2. These signalling pathways can induce significant upregulation of key proteins including VEGF, heat shock proteins (HSP’s), interleukins, and hypoxia-inducible factor 1 alpha. HSP’s and HIF-1α are also seen to be elevated in response to environmental changes such hypoxia and hyperthermia, and both proteins have to capacity to increase responses to circulating factors via interaction with receptor presentation, signal pathways, or both. Created in BioRender