Vascular endothelial growth factor (VEGF) stimulates neurogenesis <i>in vitro</i> and <i>in vivo</i>

TLDR

Vascular endothelial growth factor (VEGF) is an angiogenic protein with neurotrophic and neuroprotective effects. The study aimed to determine whether VEGF stimulates proliferation of neuronal precursors in murine cortical cultures and adult rat brain. The authors cultured murine cortical cells and administered VEGF intracerebroventricularly in adult rats, then assessed BrdU incorporation and receptor expression. VEGF (>10 ng/ml) enhanced BrdU incorporation in immature neuronal markers and increased cell numbers by 20–30 % in vitro, and intracerebroventricular VEGF similarly boosted BrdU labeling in the SVZ and SGZ of adult rat brain via VEGFR2/Flk‑1 signaling, indicating that VEGF promotes neurogenesis by stimulating proliferation of neurons, astroglia, and endothelial cells.

Abstract

Vascular endothelial growth factor (VEGF) is an angiogenic protein with neurotrophic and neuroprotective effects. Because VEGF promotes the proliferation of vascular endothelial cells, we examined the possibility that it also stimulates the proliferation of neuronal precursors in murine cerebral cortical cultures and in adult rat brain in vivo . VEGF (&gt;10 ng/ml) stimulated 5-bromo-2′-deoxyuridine (BrdUrd) incorporation into cells that expressed immature neuronal marker proteins and increased cell number in cultures by 20–30%. Cultured cells labeled by BrdUrd expressed VEGFR2/Flk-1, but not VEGFR1/Flt-1 receptors, and the effect of VEGF was blocked by the VEGFR2/Flk-1 receptor tyrosine kinase inhibitor SU1498. Intracerebroventricular administration of VEGF into rat brain increased BrdUrd labeling of cells in the subventricular zone (SVZ) and the subgranular zone (SGZ) of the hippocampal dentate gyrus (DG), where VEGFR2/Flk-1 was colocalized with the immature neuronal marker, doublecortin (Dcx). The increase in BrdUrd labeling after the administration of VEGF was caused by an increase in cell proliferation, rather than a decrease in cell death, because VEGF did not reduce caspase-3 cleavage in SVZ or SGZ. Cells labeled with BrdUrd after VEGF treatment in vivo include immature and mature neurons, astroglia, and endothelial cells. These findings implicate the angiogenesis factor VEGF in neurogenesis as well.