Testosterone Induces Protein And MRNA Expression Of TFPI In Human Umbilical Vein Endothelial Cells Via ERK1/2 Pathway

Background and ObjectiveMale gender was found to be an independent risk factor in cardiovascular disease. Our previous studies indicated that physiological levels of testosterone had beneficial influence on hemostatic system to enhance the anticoagulant activity through stimulating the tissue factor pathway inhibitor(TFPI)levels secreted by the human umbilic vein endothelial cells (HUVEC). The aims of this study were to investigate the effects of testosterone on phosphorylation of ERK1/2 and the cellular mechanism in vitro.Methods and material1.The HUVECs were treated with physiological levels of Testosterone(3×10-8mol/L) at different time points(5,15,30,60 min).The expression of phosphorylated ERK(p-ERK)were analyzed by Western blotting with or without Flutamide(1×10-5mol/L),an androgen receptor inhibitor.2. The HUVECs were divided into culture medium only group(control), testosterone groups with physiological levels of testosterone (3×10-8mol/L),PD98059(1×10-5mol/L)treat group(PD group),PD98059 preteat group(PD+T group),The expression of TFPI antigen were analyzed by ELISA kit and the TFPI mRNA levels were analyzed by Real-time RT-PCR.Results1.A rapid phophorylation expression of ERK1/2 was observed by treatment of the HUVECs with 3×10-8mol/L Testosterone at 30 minutes. This phosphorylation could be impaired by incubation the cells with Flutamide.2.Physiological levels of testosterone (3×10-8mol/L) stimulated the secretion of TPFI significantly, ERK1/2 inhibitor PD98059 attenuated physiological testosterone's effects.Conclusion1. Physiological levels of testosterone could up-regulate the expression of phosphorylated ERK1/2(p-ERK1/2) through androgen receptor in HUVECs.2. TFPI synthesis induced by physiological levels of testosterone is mediated through ERK1/2 activation in HUVECs.