Serotonin derivative, N-(p-coumaroyl)serotonin, isolated from safflower (Carthamus tinctorius L.) oil cake augments the proliferation of normal humanand mouse fibroblasts in synergy with basic fibroblast growth factor (bFGF) or epidermal growth factor (EGF)

N-(p-Coumaroyl)serotonin (CS) with antioxidative activity is present in saf flower oil. We have reported that CS inhibits proinflammatory cytokine gene ration from human monocytes in vitro, As reactive oxygen species (ROS) affe ct cell proliferation, in this study the effect of CS on the proliferation of various cell types was examined. CS augments the proliferation of normal human and mouse fibroblast cells. The cells continue to proliferate in the presence of CS and form a transformed cell-like focus without transformati on. CS, however, does not augment the proliferation of other cell types, ei ther normal or tumor cells. CS augments the proliferation of fibroblasts in synergy with basic fibroblast growth factor (bFGF) or epidermal growth fac tor (EGF), but not with acidic FGF(aFGF) or platelet-derived growth factor (PDGF), This study using synthesized derivatives of CS reveals that the gro wth-promoting activity is not due to antioxidative activity. These findings indicate that CS is a natural compound with unique growth-promoting activi ty for fibroblasts.