Release of DPCA from supramolecular hydrogel upregulates HIF1α and induces a progenitor cell phenotype. HIF-1α stabilization and progenitor cell marker expression induced by supramolecular hydrogels. MRL mouse fibroblasts (top row), B6 mouse fibroblasts (middle row), and B6 mouse fibroblasts cultured with extract from hydrogel #12 (bottom row) were grown for 24 h in 96-well plates and immunostained with antibodies against HIF-1α, NANOG, OCT3/4, CD133, PAX7, PREF1, Nestin, von Willebrand factor (vWF), and CD34.