Protective Effects Of Osteoking On Human Umbilical Vein Endothelial Cell Injury Induced By LPS, TNF-α And PAF In Vitro

[Objective]To investigate the preventive effect of Osteoking(Herb of the Yiminority in Yunnan province) on human umbilical vein endothelial cell (HUVEC) injury, exploring its possible mechanism against deep venous thrombosis (DVT).[Methods]Lipopolysaccheride (LPS). platelet-activating factor (PAF) and tunorneerosis factor-α(TNF-α) were used to injure HUVEC in vitro, respectively. Cell viability was assessed with methyl thiazolyl tetrazolium (MTT) assay. The cultured cells were loaded by Fura-2/AM and the change of [Ca²⁺]_i in HUVEC was measured by fluorospectrophotometry. The levels of tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1(PAI-1) in the supernatant were measured by enzyme linked immunosorbent assay (ELISA).[Results] I PS(300 mg/L), TNF=α(20μg/L), and PAF(70μmol/L) significantlydecreased the absorbance values of HUVEC, markedly elevated cytosolic calcium concentrations The concentrations of t-PA had no statistically significant changes in all supernatant of cultivated cells. PAI-1, however, was significantly increased by LPS(300 mg/L),INF-α(20μg/L),and PAF(70μmol/L),as compared with the control group. Osteoking markedly inhibited LPS. INF-α. and PAF-induced [Ca²⁺]_i elevation in a dose-dependent manner Osteoking(200 mg/L, 100 mg/L, 50 mg/L) significantly reduced the concentrations of PAI-1, but had no effect on t-PA. [ Conclusion] These results demonstrated that Osteoking can produce the protectiveaction on LPS, PAF and TNF-α-induced cultured HUVEC injury and its mechanism may be related to the decrease of [Ca²⁺]_i. By inhibiting the generation of PAI-1 induced by LPS, PAF and TNF-α, Osteoking plays an essential role in keeping fibrinolytic balance, which probably is one of the mechanisms of preventing deep venous thrombosis.