In vitro ultraviolet A irradiation decreases both release ability and gene-expression of vascular endothelial growth factor-A from mast cells

Summary Ultraviolet A (UVA) rays penetrate the dermis, influencing the function of different cells, including mast cells, able to produce angiogenic factors. We investigated vascular endothelial growth factor (VEGF) release and gene‐expression from mast cells (MCs), after UVA irradiation in vitro. The release of VEGF‐A by Human MCs‐1 (HMC‐1) was induced by calcium ionophore A23187 and phorbol 12 myristate 13 acetate (PMA). Half of the cells received increasing doses of UVA (5, 25 and 50 J/cm2), the unirradiated HMC‐1 served as controls. VEGF release and VEGF‘s messenger ribonucleic acid (mRNA) were detected respectively by enzyme‐linked immunoabsorbent assay (ELISA) and reverse transcription‐polymerase chain reaction (RT‐PCR) analysis. Results showed a UVA dose‐dependent inhibitory effect on VEGF‐A release from HMC‐1. In particular, the release ability was reduced by 71.2% with 5 J/cm2; 85% with 25 J/cm2 and 86.3% with 50 J/cm2. The VEGF‐A RNA expression was reduced after UVA irradiation with 5 J/cm2. We speculated that, at least in vitro and at our experimental conditions, UVA irradiation decreases mast cells‐VEGF release and gene‐expression.