Preconditioning and Acute Effects of Flavonoids in Protecting Cardiomyocytes from Oxidative Cell Death
Figure 3
Protection compared to IR control in H9c2 cells pre-treated for 3 days with catechin, quercetin, cyanidin, and delphinidin before exposure to ischemia-reperfusion. Confluent cells were kept in 2% FBS-DMEM for 6 days including 3-day pretreatment with different concentrations of the flavonoids, and then ischemia and reperfusion were established according to the procedure described in Section 2. The flavonoids were also present during the reperfusion time. For the experiments with catechin and delphinidin, the number of live cells was counted after staining cells with acridine orange. For the experiments with quercetin and cyanidin, viability was measured by the MTT method. Data are expressed as the percent protection compared to the nonischemic and IR controls. Points are means of 4-5 wells ± SEM. *Represents versus the control ischemic-reperfused condition. In the control condition (4 days total treatment without ischemia) 40–50 μM quercetin or delphinidin showed significant cytotoxicity (inhibiting cell growth by 25–55%), while lower concentrations did not (results not shown).
