HIF1A and ischemia: Importantly, further in vivo analyses suggest that paeoniflorin may protect against retinal ischemia by downregulating ischemia-related upstream β-catenin and downstream HIF-1α, VEGF, and Ang-2, with similar effects to Wnt/β-catenin inhibitor DKK1, anti-angiogenic PEDF, and anti-VEGF Avastin.