[Protective effect of taxifolin on H2O2-induced 
H9C2 cell pyroptosis]

To explore the effect of taxifolin on H2O2-induced pyroptosis in H9C2 cells and the possible mechanisms.
 Methods: The H9C2 cells was divided into 3 groups: a control group, a hydrogen peroxide (H2O2)group and a taxifolin group. The morphology of H9C2 cells was observed by inverted phase contrast microscope. The mitochondrial membrane potential was measured by JC-1 staining and flow cytometry. The alteration of the level of reactive oxygen species (ROS) was detected by specific mitochondrial probe. The protein levels of cysteinyl aspartate specific proteinase-1 (caspase-1)was determined by Western blot. The mRNA levels of interleukin-18 (IL-18), interleukin-1a (IL-1a), interleukin-1b (IL-1b), absent in melanoma 2 (AIM2), apoptosis-associated apeck-like protein (ASC), nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3)and nucleotide-binding oligomerization domain-like receptor family caspase recruitment domain-containing protein 4 (NLRC4) were determined by reverse transcription-polymerase chain reaction (RT-PCR).
 Results: Compared with the control group, the morphology of H9C2 cells obviously changed in the H2O2-treated group, which was guadually improved in the presence of taxifolin. Compared with the control group, the mitochondrial membrane potential was markedly decreased in the H2O2-treated cells, accompanied by the increase ofROS (both P<0.05). Compared with the H2O2 group, the mitochondrial membrane potential changes in the taxifolin group was increased while the ROS was decreased, with significant difference (both P<0.05). Compared with the control group, the protein level of caspase-1 and the mRNA levels of IL-18, IL-1a, IL-1b, AIM2, ASC, NLRP3 and NLRC4 in the H2O2-treated group were significantly increased (all P<0.05), which were attenuated in the presence of taxifolin (all P<0.05).
 Conclusion: Taxifolin can protect H9C2 cells from oxidative injury, and it is able to suppress the H2O2-induced H9C2 cell pyroptosis through inhibition of AIM2, NLRP3 and NLRC4 in flammasome.