Inhibitory Activity Of Three Plants On Complement And Injuries Induced By Complement Activation

Objective: To study the anti-complementary and inhibitory activity on the injury induced by complement activation of three plants,Phyllanthus urinaria,Zanthoxylum planispinum var.dintanensis and Ligustrum robustum.Methods: The of anticomplement activity on classic pathway was screened,and the inhibitory activities of on injuries induced by complement activation in theendothelial cells were further evaluated.In briefly,a mixture of cobra venom factor(CVF)and normal human serum were incubated in a certain proportion,and the incubated products were coincubated withhuman endothelial cells.The expression of ICAM-1,VCAM-1,E-selectin,TNF-a,IL-6 in the supernatant was detected by ELISA kit,and the nuclear transcription factor NF-κB was measured by dual-luciferase reporter gene detection system.Results: The ethyl acetate fraction of P.Emblica and the principle components,Corellagin and Ellagic acid,significantly inhibited the hemolysis induced by the activation of classical complement pathway while the inhibitory effect on hemolysis induced through alternative pathway was not obvious.A further study of the classical pathway experiments showed that the ethyl acetate extracts,Corilagin and Ellagic acid interfere with the formation C3 convertase from C1,C2,and C4 on the classical complement pathway Both the extracts of the plants and the compounds Corilagin and Ellagic acid showed no significant effect on the inflammatory response of endothelial cells induced by complement activation.Endothelial cells were activated by incubation with CVF,and leadto the upregulation of cell adhesion molecules and inflammatory factors such as ICAM-1,VCAM-1,E-selectin,TNF-a,IL-6 expression.The co-incubation of the endothelial cells with extracts of Zanthoxylum planispinum var.dintanensis reduced the expression of adhesion molecule VCAM-1.The principle components of the extracts,Quercetin andits derivatives showed the down-regulation of ICAM-1,VCAM-1 and E-selectin,and interfering with the expression of inflammatory cytokine TNF-α.the phosphorylation of NF-κB p65 can be inhibited.At the same time,the extracts Z.planispinum var.dintanensis showed no obvious effect on anti-complement activity.The 50% methanol elutes of L.robustum showedeffects on the inflammationinduced by complement activation pathway in endothelial cells,and the co-incubation of a principle component of the extracts,acteoside,with endothelial cells,significant reduction of the expression of ICAM-1,VCAM-1 and E-selectin were observed,and the expression of inflammatory cytokines TNF-a and IL-6 were also down-regulated.the anti-inflammation activity were suspected to be correlated with the NF-κB pathway as the the NF-κB p65 Phosphorylation was inhibited The extracts of L.robustumshowed noobvious anti-complement activity.Conclusion: The ethyl acetate fractions of the leaves extracts,corilagin and ellagic acid all significantly inhibit the hemolytic activity of the classical complement pathway.The mechanism is related to the influence of these components on the formation of the classical pathway C3 convertase.quercetin derivatives isolated from Z.planispinum var.dintanensis and acteoside fromrom L.robustumcan effectively inhibit the expression of inflammatory factors and adhesion molecules induced by complement bypass activation.Its mechanism of action may be achieved by blocking the activation of the NF-κB signaling pathway.