The Study On Triptolide Preventing Cardiac Allograft Vasculopathy By The Signaling Pathway Of NF-κB

PART 1: Establishment of an experimental model for Thoracic aorta to abdominal aorta transplantation by applying the cuff methodObjective:To search a simple,stable,easily survive animal model to simulate the mechanism of cardiac allograft vasculopathy.Methods: Thoracic aorta of the donors were cuffed and transplanted to abdominal aorta of receipts.30 donor rats(SD),received thoracic aorta transplantation of donors(SD and Wistar),were randomly assigned to isograft control group(SD to SD,A group) and allograft experimental group(Wistar to SD,B group). Each group had 15 rats. The rats were 12 hours abrosia but can drink before pre-operation and post-operation. The sign of succeed was the animals can free move after awaking from anesthesia and can drink. In 7,28 and 56 days after transplantation, aortic grafts(n=5) were examined by pathology and studied the change on thickening of intimal hyperplasia by measuring with computer imaging analysis system.Results: In this study, neointinal hyperplasia was observed in B group characterized by intimal thickening at 28 days and more extensive thickening at 56 days. Comparing with A group and normal control group, the difference was statistically significant. While there was no obvious difference between A group and normal control group. The main lesion of B group at 56 days was that mononuclear phagocyte and extracellular matrix were accumulated on intima and the proliferation of smooth muscle cells on tunica media move to intima thatcausing intima diffuses thickening in shape of concentric circles.In B group, the change of endarterium was similar with cardiac allograf vasculopathyConclusions:It is feasible and simple to establish an experimental model for thoracic aorta to abdominal aorta transplantation by applying the cuff method. This model is suitable for the advance research in the mechanism and prevention of cardiac allograft vasculopathy.PART 2:The study on Triptolide Preventing Cardiac Allograft Vasculopathy by blocking the signaling pathway of NF-κBObjective:To investigate the effect on triptolide for the development of cardiac allograft vasculopathy and discuss the mechanism on it inhibits expression of the downstream molecules of signaling pathway by NF-κB.Methods:30 SD rats were receipts and 30 Wistar rats were donors.After established a model of cardiac allograft vasculopathy by using the same method of allograft experimental group.They were randomly assigned to two group,C group and D group.C group( triptolide intervention group):Thoracic aorta of Wistar rats were transplanted to abdominal aorta of SD rats. Triptolide(200μg/Kg/day) had been administered by gavage since one day after operation.D group(Rapamycin intervention group):Thoracic aorta of Wistar rats(male) were transplanted to abdominal aorta of SD rats. Rapamycin(1.25mg/Kg/day) had been administered by gavage since one day after operation.Each group has 15 rats. After grafts, the dead rats were collected at 7,28 and 56 days(n=5).Specimen of the parts one was control group,then to investigate pathologic condition of allograft under pathological staining and expression of NF-κB,NOS2,ICAM-1 and VCAM-1 under immunohistochemical staining.Results: 1,The results showed that at 28 and 56 days the intimal thickening of triptolideintervention group(C group) and rapamycin intervention group(B group) had significant difference with isograft control group(A group) and allograft experiment group(B group).The intimal thickening was no obvious difference between C and D. The pathology changed of C group and D group was similar with B group.Inflammatory cells infiltration,proliferation and transfer of smooth muscle cells reduced significantly. But comparing to A group,the change was obvious. 2,Vascular endothelial cell of A group and B group expressed NF-κB p65 and NOS2.Comparing with A group, the expression in B group was more obvious and more significant difference on Integrated Optical Density.The expression of NF-κB p65,VCAM-1,ICAM-1and NOS2 in endothelial cell reduced significantly in C group and Integrated Optical Density were obvious difference with A group and B group.Conclusions: 1. NF-κB p65 and intercellular adhesion molecule-1(VCAM-1,ICAM-1) and NOS2 participate in occurrence and development of cardiac allograf vasculopathy 2.Triptolide can slow the progression of cardiac allograf vasculopathy by blocking the signaling pathway of excessive activation NF-κB.Curative effect is similar with rapamycin.