Effect of VEGF and minoxidil on the production of arachidonic acid metabolites by cultured hair, dermal papilla cells

The aims of this study were to investigate : (1) the production of all arachidonic acid metabolites in hair dermal, papilla cells (DPC) and (2) the effects of minoxidil and vascular endothelial growth factor (VEGF) on this production. Eicosanoid synthesis was evaluated in culture medium after incorporation of tritiated arachidonic acid into DPC membrane phospholipids. Compared to controls, exposure of DPC to 1 μM 12-O-tetradecanoyl phorbol 13-acetate did not stimulate arachidonic acid metabolism, however exposure to calcium ionophore A23187, produced large amounts of eicosanoids, consisting mainly of 273% PG6KF 1α , 176% of PGE 2 and 68% LTB 4 . A good correlation was found with ELISA and radioassay techniques for total synthesis of major metabolites. The ELISA technique was also used to investigate the effects of minoxidil and VEGF on DPC production of three arachidonic acid metabolites : prostaglandins 6KF 1α , E 2 and leukotriene B 4 , before and after stimulation with A23187. High concentrations of VEGF induced an activation of the production of these metabolites, and a low concentration of minoxidil (12 μM) inhibited PG6KF 1α production but stimulated that of PGE 2 and LTB 4 . These data confirm the implication of VEGF and minoxidil in the modulation of eicosanoid production by hair, dermal papilla cells.