In vitro induction of endothelial cell fibrinolytic alterations by Nigella sativa

The effect of Nigella sativa (NS) L. oil (blackseed oil) on the fibrinolytic system of the human umbilical vein (HUV) and human uterine arterial (HUA) endothelial cells (ECs) in culture was studied. Both of them showed a concentration-dependent increase in tissue-type plasminogen activator (t-PA). A maximum effect was achieved with 50 μg oil/ml conditioned medium (CM) (1.3±0.15 ng/10 4 cells/24 h vs. control 0.7±0.06 ng/10 4 cells/24 h, and 0.38±0.04 ng/10 4 cells/24 h vs. control 0.24±0.02 ng/10 4 cells/24 h, for HUVEC and HUA-EC, respectively). At 100 μg/ml, there was a significant change in the amount of t-PA antigen produced by either HUVEC or HUA-EC (1.0±0.1 ng/10 4 cells/24 h or 0.28±0.02 ng/10 4 cells/24 h) as compared to control CM from cells grown under control conditions, but still less than that recorded at 50 μg oil/ml. Plasminogen activator inhibitor-type 1 increased the CM significantly and concentration-dependently in both cells. For HUVEC, the maximum effect was achieved at a concentration of 100 μg/ml (257.7±8.0 ng/10 4 cells/24 h vs. control 72.7±3.8 ng/10 4 cells/24 h). HUA-EC showed the maximum effect at a concentration of 100 μg/ml (171.6±4.4 ng/10 4 cells/24 h vs. control 53.8±3.7 ng/10 4 cells/24 h). This study suggests a role for NS oil in modulating the balance of fibrinolysis/thrombus formation by modulating the fibrinolytic potential of endothelial cells.