Study on tetramethylpyrazine protecting PC12 cells from injury induced by H_2O_2

Objective To analyze the protection of tetramethylpyrazine to PC12 cells from apoptosis induced by H2O2 and to explore the inhibition mechanisms of oxygen free radical injury in cerebral ischemia.Methods After the PC12 cells were pretreated by tetramethylpyrazine,H2O2 was added to induce the apoptosis of PC12 cells.Various methods,including CCK-8live cell test,Hoechst-33342 staining,flow cytometry and quantitative reverse transcription polymerase chain reaction(qRT-PCR),were used to analyze the mechanisms involved in the process.Results After the different concentrations(0,0.1,1,10mmol/L)tetramethylpyrazine pretreatment,there were no large number of apoptotic bodies formed in PC12 cells and the viability(%)of PC12 cells were(51.2±4.64)%,(58.5±7.46)%,(73.8±2.94)% and(81.0±6.06)% respectively(F=146.9,P0.05).Moreover,in PC12 cells,the rate of Bax/Bcl-2dropped(F=2.14,P0.05),the electric potential of mitochondrial membrane enchanced,activity of Caspase 3and Caspase 9decreased(Caspase 3:F=1.59,P0.05;Casapse 9:F=4.98,P0.05).Conclusion The pretreatment with tetramethylpyrazine could reduce the apoptosis of PC12 cells damaged by H2O2 and inhibit oxygen free radical injury.