The Change Of Coagulation And Fibrinolysis Related Factors Expression In HUVECs Infected With Dengue Virus 2

Research Background and Objective: The aim of this study was to elucidate the effects of Dengue virus on the expression and secretion of tissue Factor(TF), tissue factor inhibitor(TFPI-l), thrombomodulin(TM), tissue plasminogen activator(tPA) and plasminogen activator inhibitor type-1 (PAI-1) in vein endothelial cells for a better understanding of hemorrhage and plasma penetration mechanisms of DV2 infection at the site of entry.Methods: Cultured human umbilical vein endothelial cells(HUVECs) were infected by DV2 for different hours. Cell viability was then determined by Cell counting kit-8(CCK-8), and lactate dehydrogenase (LDH) in mitochondria of HUVECs was measured to assess cell viability. tPA and PAI-1 viability in the media were assayed by fibrin overlay and reverse fibrin autograph, respectively. Cytoplasmic RNA from HUVECs was extracted by the Trizol method and and mRNA levels of TF, TFPI, TM, tPA and PAI-1 were assayed by reverse transcript-polymerase chain reaction(RT-PCR) method respectively.Results: DV2(M0I=2) did not produce cell toxicity as shown by cell viability according to LDH determination in culture media. DV2 infection inhibited the TFPI mRNA expression(p<0.05) within 12h, but the inhibition effect weakened as time past, and recovered normal level after 48h. However, DV2 infetion did not elevate TF mRNA level in HUVECs significantly. At the same time, TM mRNA level in DV2 group was enhanced significantly compared to control group(P<0.05), and TM mRNA concentration of DV2 group reached the peak after 24h, then began todeclined , and recovered to normal level after being infected over 72h. tPA viability of DV2 group was risen (p<0.05), while PAI-1 viability remained normal level. Moreover, DV2 infection induced a marked increase of the levels of tPA mRNA up to 12h, then began to descend, but remained higher level up to 72h, however, DV2 infetion did not chang PAI-1 mRNA level in HUVECs(p>0.05).Conclusion: DV2(M0I=2) did not show signs of cell toxicity, and inhibited TFPI mRNA expression notably, but it did promote the expression of TF mRNA. At the same time, the level of TM mRNA in DV2 group was higher than that of control group. As result, TM mRNA expression in HUVECs can inhibit thrombin viability, DV2 promoted the expression of tPA mRNA, inducing an increase tPA viability, and did not chang PAI-1 mRNA expression. The time-dependent increase in the DV2 that induced tPA mRNA expression and increased viability can neutralize of the PAI-1 viability. Therefore, A switch of the local coagulant and anticoagulant path balance toward increased anticoagulant activity-, increased tPA mRNA expression and viability by VECs may shift the local balance to increased fibrinolytic capacity in blood. A shift of local balance to increased anticoagulant and fibrinolysis capacity, which may increase hemorrhage risk, may play important roles in the pathogenic development of DHF/DSS.