[Shenmai injection protects mitochondria from oxidative injury in myocardial cells and its mechanism].

OBJECTIVE: To investigate the effect of Shenmai injection on myocardial cells with oxidative injury and the underlying mechanisms. METHODS: Tert-butyl hydroperoxide (t-BHP) was used to induce the oxidative stress in H9c2 myocardial cells. The cell viability and ATP level were evaluated using MTT-colorimetric method and CellTiter-Glo luminescent cell viability assay. The oxygen respiration rate was examined by Clark oxygen electrode. Pyruvate and pyruvate dehydrogenase (PDH) levels were evaluated by ELISA kit. Western blot and quantitative real-time RT-PCR were employed to evaluate the expression of pyruvate dehydrogenase alpha 1(PDHA1) and pyruvate dehydrogenase kinase 1(PDK1). RESULTS: Shenmai injection significantly improved viability and respiration of H9c2 myocardial cells after t-BHP injury (P<0.05 or P<0.01). It increased ATP contents by consuming pyruvate and increasing PDH level (P<0.05 or P<0.01). Furthermore, Shenmai injection had the tendency to increase protein expression of PDHA1(P<0.05) and decrease mRNA expression of PDK1 (P>0.05). CONCLUSIONS: Shenmai injection protects mitochondria from oxidative stress by increasing PDH level, which indicates that it may improve energy metabolism of myocardial cells.