Vascular endothelial growth factor-containing conditioned medium from PFOS-exposed human granulosa cells promotes...

Perfluorooctanesulfonic acid (PFOS) is a persistent environmental pollutant associated with reproductive dysfunction. We investigated the acute effects of PFOS in HGrC1 human granulosa cells. Cells were initially exposed for 48 h to two concentrations of PFOS: 15 nM, representing levels found in human follicular fluid, and 10 µM, corresponding to serum concentrations observed in occupational exposure scenarios. Global mRNA sequencing revealed that exposure to 10 µM PFOS upregulated six genes, including vascular endothelial growth factor A (VEGFA). Different experimental conditions showed robust induction of this gene, with maximal increases at 25 µM PFOS after 6 and 12 h, without overt cytotoxicity. PFOS at 25 µM rapidly activated protein kinase B (AKT) and cAMP response element-binding protein (CREB), while inhibition of the phosphoinositide 3-kinase (PI3K)/AKT pathway prevented VEGFA mRNA upregulation. PFOS decreased VEGFA protein levels in cells, but induced VEGFA protein secretion into the medium of HGrC1 cells, independently of PI3K/AKT and protein kinase A (PKA) signaling. Conditioned media from PFOS-exposed HGrC1 cells enhanced the migration of both HGrC1 and human endothelial EA.hy926 cells and promoted endothelial tube formation in EA.hy926 cells. Immunodepletion of VEGFA from the conditioned media of PFOS-exposed HGrC1 cells returned parameters of tube formation to control levels, while recovery of VEGFA activity restored tube formation to levels observed after exposure to conditioned medium from PFOS-exposed HGrC1 cells. These results suggest that VEGFA is the key mediator of the observed pro-angiogenic effects in endothelial cells providing a novel insight into the mechanisms of PFOS action on ovarian function.