Characterization of Hepatotropic Small Molecule Inhibitors of Hypoxia Inducible Factor Prolyl Hydroxylase in the Prevention of Oxygen-Induced Retinopathy.

Retinopathy of prematurity (ROP) blinds severely premature infants and is caused by oxygen supplementation. Hypoxia-inducible factor (HIF) stabilization during hyperoxia can prevent oxygen-induced retinopathy (OIR), the experimental correlate of ROP. Stabilization of hepatic HIF-1 alone can prevent OIR while contemporaneously protecting other organ systems, such as the lung and brain, from oxygen toxicity. However, HIF stabilization in central nervous system (CNS) oligodendrocytes reduces myelination. Here, we report the synthesis of small molecules specifically designed to not cross the blood-brain barrier based on a prodrug structure susceptible to hepatic carboxylesterases that release active drug. Twenty compounds were synthesized and rank ordered by Western blot, hypoxia response element binding, and reporter gene analysis. The lead compound prevented OIR, maintained normal CNS myelination, preserved the electroretinogram b-wave, and protected astrocytes. Strategies such as this might be broadly applicable to target specific hepatic functions while limiting off-target effects in other organs.