ERK1/2 and HIF1α Are Involved in Antiangiogenic Effect of Polyphenols-Enriched Fraction from Chilean Propolis

Propolis has been shown to modulate the angiogenesis in both in vitro and in vivo models. Thus, we aimed to evaluate the antiangiogenic properties of an ethanolic extract of Chilean propolis (EEP) and Pinocembrin (Pn). Migration, formation of capillary-like structures of endothelial cells, and sprouting from rat aortic rings were used to assess the antiangiogenic properties of EEP or Pn. In addition, microRNAs and VEGFA mRNA expression were studied by qPCR. ERK1/2 phosphorylation and HIF1α stabilization were assessed by western blot. EEP or Pn attenuated the migration, the capillary-like tube formation, and the sprouting in the in vitro assays. In addition, the activation of HIF1α and ERK1/2 and the VEGFA mRNA expression was significantly inhibited in a dose-dependent manner. In summary, these results suggest that HIF1α and ERK1/2 phosphorylation could be involved in the antiangiogenic effect of Chilean propolis, but more studies are needed to corroborate these findings.