Tmb-8 On Endothelial Cells, Protective Effect And Its Mechanism

Endothelium covers all over the blood vessel in the inner side, it is important to regulations of many biological system and physiological functions. There exist great morphological and functional changes of endothelial in the progress of many cardiovascular diseases. Therefore, people pay more attention to research and development of drug that can protect endothelial cells in the prevention and therapy of cardiovascular disease. TMB? is an antagonist which inhibits calcium ion release from sarcoplasmic reticulum . It is found that TMB-8 can stimulate nitric oxide release from endothelial cell, and inhibit the proliferation of vascular smooth muscle cells as well as prevent oxidation. Based on these research, we use hydrogen and lysophosphatidylcholine to induce damage on culture bovine aortic endothelial cell, in order to evaluate the protective effects of TMB-8 on endothelial cells and study the mechanism. Endothelial cells were randomly divided into 6 experimental groups(n=8) . They were treated with medium DMEM alone, hydrogen peroxide(H202) alone, H202 plus nifedipine lumol 1J1, H202 plus TMB-8 1,10,30 lumol U?respectively. After the nifedipine or TMIB-8 incubate with endothelial cells for two hours, the hydrogen peroxide was added into each group except the normal control group, the concentration of hydrogen peroxide is 1 Oumol JJ1, and endothelial cells were incubated with hydrogen peroxide for 4 hours. At the end of incubation period, the morphological changes of endothelial cells were recorded, the media were collected to analyze the content of lactic dehydrogenase(LDI-f), the vitality of cells were assayed by MiTE chromatornetry, as well as the malondialdehyde(MDA), superoxide dismatase(SOD) and glutathione peroxidase(GSH-PX) in the cells were assayed. It was observed that LDH and MDA were increased and SOD, GSH-PX were decreases in the H)2 damaged group, While the quantity of formazan forming in the H202 damaged group were decreased. TMB-8( 1,1 0,30umol JJ? could concentration-dependently increase the activity of SOD, GSH-PX, and decrease the level of LDH,MDA, as well as TMB-8 could increased the quantity of formazan. The morphological changes induced by 1-1202 were also improved. After endothelial cells incubate with Lysophospha- tedylcholine(12.5ug ml? for 24 hours, the morphological changes occurs: the cells become thin and long, the intercellular space were enlarged, and small part of cells dropped off the culture plate. LDH leaked from the cell was significant increased, and the activety of SOD, GSH-PX was decreased, the quantity of plasminogen activator inhibitor was enhanced. These changes could be provented by incubating with TMB-8 (1,10,30umol J1) in advance. These results suggest that the protective effect of TMB-8 may be related with the reducing of cell permeability, the improving of mitochondrial function and antioxidant effect. In addition, TMB-8 may increase the activity of fibrinolysis.