Safrole oxide induces human umbilical vein endothelial cell transdifferentiation to 5-hydroxytryptaminergic neuron-like cells through tropomyosin receptor kinase A/cyclooxygenase 2/nuclear factor-kappa B/interleukin 8 signaling

► SFO induced HUVEC transdifferentiation into 5-hydroxytryptaminergic neurons. ► COX-2, ROS, IL-8 and NF-κB were involved in this transdifferentiation process. ► SFO induced HUVEC transdifferentiation through TrkA. ► After blockade of TrkA, the much higher level of ROS induced cell apoptosis.