proangiogenic

Proangiogenic describes any molecule, cell, or process that promotes angiogenesis, the growth of new blood vessels from existing vasculature. It is a central concept in development, wound healing, and regenerative medicine, and it also plays a role in conditions where blood vessel formation is dysregulated.

Common proangiogenic factors include vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF-2), angiopoietins, platelet-derived growth factor (PDGF), and insulin-like growth factor (IGF). Hypoxia induces proangiogenic signaling primarily through hypoxia-inducible factor 1 (HIF-1), which upregulates VEGF. Activation of VEGF receptors and other proangiogenic receptors stimulates endothelial cell proliferation, migration, and organization into capillary-like tubes; the process is aided by extracellular matrix remodeling via matrix metalloproteinases and recruitment of supporting cells such as pericytes.

Physiologically, proangiogenic activity supports embryonic development, placentation, and tissue repair after injury or ischemia. Pathologically, it can enable tumor growth and progression and contribute to ocular neovascular diseases. Therapeutically, proangiogenic strategies aim to enhance vascularization in wounds or engineered tissues, while anti-angiogenic approaches target proangiogenic pathways in cancer and retinopathies.

Research and clinical assessment rely on in vitro assays of endothelial proliferation, migration, and tube formation, and in vivo models such as the Matrigel plug or chorioallantoic membrane assay. Measuring circulating or local levels of VEGF and related factors aids evaluation. The balance between proangiogenic and anti-angiogenic signals determines vascular growth in a given context.