Dimethyloxalylglycine preserves the intestinal microvasculature and protects against intestinal injury in a neonatal mouse NEC model: role of VEGF signaling

BackgroundNecrotizing enterocolitis (NEC) is a devastating neonatal disease characterized by intestinal necrosis. Hypoxia-inducible factor-1α (HIF-1α) has a critical role in cellular oxygen homeostasis. Here, we hypothesized that prolyl hydroxylase (PHD) inhibition, which stabilizes HIF-1α, protects against NEC by promoting intestinal endothelial cell proliferation and improving intestinal microvascular integrity via vascular endothelial growth factor (VEGF) signaling.MethodsTo assess the role of PHD inhibition in a neonatal mouse NEC model, we administered dimethyloxalylglycine (DMOG) or vehicle to pups before or during the NEC protocol, and determined mortality and incidence of severe intestinal injury. We assessed intestinal VEGF by western blot analysis and quantified endothelial cell and epithelial cell proliferation following immunofluorescence.ResultsDMOG decreased mortality and incidence of severe NEC, increased intestinal VEGF expression, and increased intestinal villus endothelial and epithelial cell proliferation in experimental NEC. Inhibiting VEGFR2 signaling eliminated DMOG’s protective effect on intestinal injury severity, survival, and endothelial cell proliferation while sparing DMOG’s protective effect on intestinal epithelial cell proliferation.ConclusionDMOG upregulates intestinal VEGF, promotes endothelial cell proliferation, and protects against intestinal injury and mortality in experimental NEC in a VEGFR2 dependent manner. DMOG’s protective effect on the neonatal intestinal mucosa may be mediated via VEGFR2 dependent improvement of the intestinal microvasculature.