ADORA2B , transcriptionally suppressing by MYC , promotes ferroptosis of chondrocytes via inhibition of the PI3K/Akt pathway in mice with osteoarthritis

Recent studies have shown that chondrocyte ferroptosis contributes importantly to the pathogenesis of osteoarthritis (OA). However, it is largely unknown how it is regulated. In this study, the data sets GSE167852 and GSE190184 were downloaded from the Gene Expression Omnibus (GEO) database, and 161 differentially expressed genes (DEGs) related to ferroptosis were screened by bioinformatics analysis. Subsequently, ADORA2B was screened as a candidate gene from DEGs, which was significantly upregulated in palmitic acid (PA) treated chondrocytes. CCK-8, EdU, Western blotting, and ferroptosis-related kits assays demonstrated that knockdown of ADORA2B constrained ferroptosis and promoted viability of chondrocytes. Overexpression of ADORA2B promoted ferroptosis, while the PI3K/Akt pathway inhibitor LY294002 reversed the promotion of ADORA2B on ferroptosis. Dual-luciferase reporter gene assay and chromatin immunoprecipitation (ChIP) assays indicated MYC was a transcription suppressor of ADORA2B, and overexpression of MYC promoted the viability, and inhibited the ferroptosis of chondrocytes, while ADORA2B overexpression abated the promotion of MYC on chondrocyte viability and the inhibition on ferroptosis. In vivo experiments showed that MYC overexpression alleviated cartilage tissue damage in OA mice, which was able to reversed by ADORA2B overexpression. In summary, ADORA2B, transcriptionally suppressing by MYC, promotes ferroptosis of chondrocytes via inhibition of the PI3K/Akt pathway. Thus, ADORA2B can be used as a potential treatment target for ferroptosis-related diseases.