Beneficial Effects Of Puerarin On Vascular Smooth Muscle Cell Injury Induced By Hydrogen Peroxide

OBJECTIVE: To investigate the mechanism and the beneficial effects of puerarin on the vascular smooth muscle cell injury induced by hydrogen peroxideMETHODS: Following after the estabilishment of a model of the H₂O₂-induced vascular smooth muscle cells apoptosis, the apoptosis of the cells were measured by flowcytometry and Hoechst 33258 staining; the DNA fragmentation was analyzed by agarose gel electrophorsis; the viability percentage of cells was measured using MTT assay. The expression of Cystein-asparate protease-3 (Caspase-3) and NF-κBp65 in vascular smooth muscle cells was detected by immunocytochemical method. The expression of Caspase-3, Bax, Bcl-2 mRNA was detected by reverse transcription polymerase chain reaction (RT-PCR); we observed the activity of the superoxide dismutase (SOD), glutathion (GSH) and lactic acid dehydrogenase (LDH), and the change of the content of malonaldehyde (MDA) in each group by chromatometry.RESULTS: 1. Hydrogen peroxide could significantly induce the apoptosis of VSMC in serum free medium, decrease the activity of SOD, GSH and the cell viability, increase the activity of LDH, the content of MDA and the expression of Caspase-3, Bax and NF-κBp65 and enhance the ratio of Bax/Bcl-2. 2. The puerarin of different concentrations pretreatment could attenuate the above-mentioned effects in a dose-dependent manner.CONCLUSIONS: 1. Puerarin can protect apoptotic vascular smooth muscle cells induced by H₂O₂ markedly; 2. Puerarin could inhibit oxidative stress in a dose-dependent manner, which could protect smooth muscle cells against oxygen free radical; 3. The protective effect of puerarin on vascular smooth muscle cell apoptosis is performed partly by down-regulating the expression of Caspase-3, Bax and NF-κB and decreasing the ratio of Bax/Bcl-2.