To investigate the effect and mechanism of Poria cocos polysaccharides on doxorubicin-induced myocardial cell injury.

AC16 cardiomyocytes were randomly divided into 5 groups：control group，model group，low dose group，medium dose group and high dose group.The cells in the model group，low dose group，medium dose group and high dose group were stimulated with adriamycin（1μmol/L）for 12 hours.The cells in the low，medium and high dose groups were treated with 5，10 and 20μmol/L Poria cocos polysaccharides for 24 hours，respectively.Methyl thiazol tetrazolium（MTT）assay was used to analyze the proliferation ability of each group of cells.The levels of inflammatory factors，superoxide dismutase（SOD）and malondialdehyde（MDA）in cell culture medium were detected by enzyme-linked immunosorbent assay（ELISA）.The level of reactive oxygen species in each group was detected by reactive oxygen species fluorescence probe.The apoptosis rate of each group was detected by flow cytometry.Protein immunoblot tested the protein expressions of nuclear factor erythroid 2-related factor 2（Nrf2）and hemoxygenas-1（HO-1）in each cell.

Compared with those of the control group，the cell proliferation ability，SOD level，Nrf2 and HO-1 protein expressions were decreased，and inflammatory factors，MDA level and apoptosis rate were increased in the model group（P<0.05）.Compared with those of the model group，the proliferation ability，SOD level，Nrf2 and HO-1 protein expressions of AC16 cells were gradually increased，and the inflammatory factors，MDA level and apoptosis rate were gradually decreased with the increase of the dose of Poria cocos polysaccharides（P<0.05）.

Poria cocos polysaccharides can alleviate doxorubicin-induced myocardial cell injury by inhibiting inflammation and oxidative stress，and this process is related to the activation of Nrf2/HO-1 signaling pathway.