ABSTRACT
AIM: To investigate the effect of silymarin on homocysteine-induced cell viability and apoptosis in human umbilical vein endothelial cells (HUVECs). METHODS: Cell viability was analyzed by using MTT and LDH assay. Apoptotic cells were detected by using DNA fragmentation and flow cytometric analysis. The level of intracellular reactive oxygen species (ROS) and the potential of mitochondrial membrane were determined by flow cytometric assay. The activity of caspase-3, -6 and -9 were measured with microplate spectrofluorometer. Protein levels were examined by Western blotting. RESULTS: Treatment of cultured HUVECs with HCY for 48 h induced a significant decrease in cell viability, and the percentage of apoptosis increased to 76.8%. The level of intracellular ROS and activity of caspase-3, -6 and -9 enhanced, and the red/green ratios of mitochondrial membrane decreased. However, simultaneous treatment with silymarin exhibited cytoprotective effects, reduced formation of the DNA ladder, prevented the levels of Bax and Bcl-2 proteins and the accumulation of ROS as well as caspase-3, -6 and -9 activation, reconverted the potential of mitochondrial membrane, and the percentage of apoptosis/necrosis was significantly decreased to 12.7% in a dose-dependent manner. CONCLUSION: These results demonstrate that silymarin has the protective capacity to antagonize HCY-induced apoptosis in HUVECs. The antiapoptotic action of silymarin may be partially dependent on an anti-oxidative stress effects, inhibition of caspases activity, and maintenance of mitochondria function.
ABSTRACT
AIM:To investigate the effects of grasp seed procyanidins(GSP) on homocysteine-induced proliferation and migration in vascular smooth muscle cells(VSMC) and related molecular mechanisms.METHODS: Cell count and -TdR assay were used for detecting cell proliferation and DNA synthesis,ELISA assay was used for detecting inflammatory response,DCFH-DA assay for examining the levels of reactive oxygen species(ROS),Western blotting for detecting protein expression.RESULTS: Homocysteine(0.1-1 mmol/L) increased VSMC proliferation and migration,and the levels of ROS were in a dose-dependent manner.The results of Western blotting showed that homocysteine significantly increased the expression of MCP-1,IL-6 and TNF-?.However,Compared with control group,in GSP(5-20 g/L) group,the increased VSMC proliferation,migration and the production of ROS and the expression of MCP-1,IL-6 and TNF-? mediated by homocysteine were markedly suppressed.EMSA showed that in GSP treatment group,the NF-?B activation was also almost completely inhibited.CONCLUSION: GSP inhibits homocysteine-induced VSMC proliferation,migration and inflammatory response through interfering with ROS dependent on NF-?B signal pathway.