The retinoid agonist Tazarotene promotes angiogenesis and wound healing.
Zen AA., Nawrot DA., Howarth A., Caporali A., Ebner D., Vernet A., Schneider JE., Bhattacharya S.
Therapeutic angiogenesis is a major goal of regenerative medicine, but no clinically approved small molecule exists that enhances new blood vessel formation. Here we show, using a phenotype-driven high-content imaging screen of an annotated chemical library of 1280 bioactive small molecules, that the retinoid agonist Tazarotene, enhances in vitro angiogenesis, promoting branching morphogenesis, and tubule remodeling. The pro-angiogenic phenotype is mediated by Retinoic Acid Receptor (RAR) but not Retinoic X Receptor (RXR) activation, and is characterized by secretion of the pro-angiogenic factors Hepatocyte Growth Factor (HGF), Vascular Endothelial Growth Factor (VEGFA), Plasminogen Activator, Urokinase (PLAU) and Placental Growth Factor (PGF), and reduced secretion of the anti-angiogenic factor Pentraxin-3 (PTX3) from adjacent fibroblasts. In vivo, Tazarotene enhanced the growth of mature and functional microvessels in Matrigel implants and wound healing models, and increased blood flow. Notably, in ear punch wound healing model, Tazarotene promoted tissue repair characterized by rapid ear punch closure with normal-appearing skin containing new hair follicles, and maturing collagen fibers. Our study suggests that Tazarotene, an FDA-approved small molecule, could be potentially exploited for therapeutic applications in neovascularization and wound healing.