Raw 264.7 macrophages

RAW 264.7 macrophages and H9C2 cells were purchased from China Infrastructure of Cell Line Resources (Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences). They were incubated with Dulbecco’s modified Eagle’s medium (DMEM; Corning, United States) supplemented with 10% fetal bovine serum (FBS, Corning, United States), penicillin (100 U/mL; Corning, United States) and streptomycin (100 μg/mL; Corning, United States) at 37°C in a humidified atmosphere of 5% CO₂.

RAW264.7 macrophages were purchased from China Infrastructure of Cell Line Resources (Beijing, China), and were cultured in Dulbecco’s modified Eagle’s medium (DMEM, Invitrogen) with 10% FBS, 2 mM L-glutamine (Invitrogen), 100 U/ml penicillin, and 100 μg/mL streptomycin (Invitrogen). The cells were cultured at 37°C, with 5% CO₂, in a humidified atmosphere. Every 2-3 days, the cell medium was changed. When the cells became 70% to 80% confluent, they would be passaged.

RAW 264.7 macrophages and rat myocardial H9C2 cell used in the present study were purchased from China Infrastructure of Cell Line Resources and were both cultured at 37 °C under 5% CO2 humidified atmosphere, with DMEM supplemented with FBS (10%), Penicillin (100 U/mL) and Streptomycin (100 μg/mL). To screen the non‐toxic concentrations of danshen, H9C2 and RAW264.7 cells were seeded onto 96‐well plates and incubated with danshen (100 ~ 1200μg/mL) for 24 hours. Then, Cell Counting Kit‐8 (CCK8, Dojindo, Kumamoto, Japan) was utilized to assess the cell viabilities by measuring absorbance at 450 nm under Microplate reader (perkin‐elmer, Waltham, MA and United States).
To evaluate the effects of danshen on LPS‐induced macrophages, RAW264.7 cells were exposed to LPS (1 μg/mL) for 24 hours with/without danshen. Cell supernatants for conditioned media (CM) were collected for further experiments. To investigate the effects of danshen on CM‐stimulated cardiomyocytes, H9C2 cells were pre‐treated with danshen for 6 hours and then stimulated with CM (with/without danshen) for 24 hours.