Figure 1. Cryptotanshinone (CPT) protected H9c2 cardiomyocytes against doxorubicin-induced damage. Chemical structure of CPT (A). Cytotoxicity of CPT in vitro (B). Effects of CPT on the viability of H9c2 cardiomyocytes induced by various concentrations of doxorubicin at the indicated time-points (C). Cell-size measurement of H9c2 cardiomyocytes (green-F-actin staining) induced by doxorubicin in the presence or absence of CPT treatment (D). The number of apoptotic H9c2 cells determined using Annexin V/ Propidium Iodide (PI) staining (E). Assessment of reactive oxygen species (ROS) by flow cytometry analysis after treatment with doxorubicin in the presence or absence of CPT (F). The JC-1 monomers and aggregates of H9c2 cells stimulated by doxorubicin with/without CPT detected by flow cytometry (G). Values are mean ± standard error of the mean; all experiments were performed in three replicates. *Significant difference (P<0.05), DOX + CPT vs DOX.