Ocifisertib alleviates the gasdermin D-independent pyroptosis of nucleus pulposus cells by targeting GSDME

This study aimed to elucidate the cellular and molecular mechanisms of GSDME in GSDMD independent nucleus pulposus (NP) cell pyroptosis. We analyzed microarray datasets to identify differentially expressed genes (DEGs) in the progression of intervertebral disc degeneration (IDD) and conducted Gene Ontology analysis to elucidate DEGs-participated biological processes. We utilized lipopolysaccharides (LPS) to treat human primary NP cells to establish pyroptosis cell model. And siRNA was used to simulate a GSDMD-deficient environment. We used several regulators to figure out how GSDME was participate in pyroptosis via a GSDMD independent pathway. The molecular docking was conducted to identify compound that could possibly bind to GSDME and suppress its cleavage. Finally, Ocifisertib was intraperitoneally administered into IDD rat model to explore its therapeutic potential. Pyroptosis was activated in IDD. In vitro, LPS induced NP cell pyroptosis by promoting the cleavage of GSDMD and GSDME. In the absence of GSDMD, the cleavage of GSDME compensatively upregulated to mediate pyroptosis. Ocifisertib alleviated pyroptosis-mediated IDD by inhibiting GSDME cleavage in annulus fibrosus puncture-induced IDD rat model. Our study provides evidence that the cleavage of GSDME aggravates IDD by accelerating NP cell pyroptosis and demonstrates that Ocifisertib has therapeutic potential in IDD treatment.