Objective: To investigate the effects of Tanshinone IIA (Tan IIA) on procoagulant activity (PCA) of human ECV304 cells induced by acute promyelocytic leukemia cell line NB4 cells.
Methods: ECV304 monolayers were respectively incubated for different hours at 37 degrees C in the conditioned media (CM) of NB4 cells treated with 0.5 microg/mL Tan IIA(Tan IIA-NB4-CM), 0.3 microg/mL all-trans retinoidic acid (ATRA)(ATRA-NB4-CM), DMSO(DMSO-NB4-CM) or the RPMI1640 medium. ECV304 lysates were tested for PCA using the one-stage clotting assay as well as for tissue factor activity (TF: Act) using the chromogenic substrate assay; ECV304 cell monolayers were incubated for different hours at 37 degrees C in a medium system including 0.5 microg/mL Tan IIA and Tan IIA-NB4-CM, and the ECV304 cell lysates were tested for PCA in the same way as above. Also they were controlled by 0.3 microg/mL ATRA, DMSO or RPMI1640 medium.
Results: (1) The conditioned mediums from 0. 5 microg/mL Tan IIA that treated NB4 cells for 24, 72 and 120 hours respectively could elevate PCA of ECV cells, and this capability developed with the time of reaction. ATRA did the same as Tan IIA (P > 0.05). (2) 0.5 microg/mL Tan IIA down-regulated the PCA of ECV304 cells induced by Tan IIA-NB4-CM, and the inhibitory effects increased with time, reaching the highest at 120 hours. (3) Tan IIA120 h-NB4-CM up-regulated TF:Act of ECV304 cells, and the effect increased with time. (4) 0. 5 microg/mL Tan IIA down-regulated PCA and TF: Act of ECV304 cells induced by Tan IIA-NB4-CM, and the inhibitory effect increased with time; simultaneously, the test was controlled with 0.3 microg/mL ATRA, the effects on PCA and TF: Act were not significantly different (P > 0.05).
Conclusion: Tan IIA-NB4-CM can increase the levels of PCA and TF: Act of ECV304 cells through some unidentified factor; however, Tan IIA can obviously decrease the PCA and TF: Act levels of ECV304 cells induced by Tan IIA-NB4-CM.