Screening of potent RIPK3 inhibitors to attenuate necroptosis and inflammation in mouse traumatic brain injury models

Necroptosis is a type of cell death that occurs when cells are exposed to external stressors such as inflammation, infections, or injury. In necroptosis, cells use a different set of proteins including: receptor-interacting kinase 1 (RIPK1 or RIP1), receptor-interacting kinase 3 (RIPK3 or RIP3) and the phosphorylation of its substrate mixed lineage kinase domain-like protein (MLKL) and pathways to trigger their own death. Mutations in the gene encoding RIPK3 have been associated with many diseases, including neurodegenerative diseases, neuroinflammatory diseases, inflammatory diseases，tumors, and it is being studied as a potential target for inflammatory injury therapy. RIPK3 has also been implicated in the pathology of neuroinflammation following Traumatic brain injury and is currently being explored as a potential therapy. We screened through necroptosis blocking compounds, a library of FDA-approved compounds. We found four compounds:1D6-Foretinib GSK1363089; 15F6-Poziotinib (HM781-36B); 15F9-Dasatinib monohydrate; 15A10-Pexmetinib (ARRY-614); acts as potent inhibitors of necroptosis (Necroptosis Blocking Compounds, NBCs) by blocking the RIPK3 kinase activity. These four compounds effectively block necroptosis induced by death receptor ligands Toll-like receptors as well as viral infections in human, rat and mouse cells. The cellular activation of RIPK3 and MLKL stimulated by necroptosis was strongly inhibited by NBCs. The compounds are promising for targeting RIPK3 kinase activity, thereby preventing necroptosis and inflammatory responses. In our study, we explored the role of NBCs in neuroprotection after traumatic brain injury. It's effectiveness in traumatic brain injury animal models and favorable safety profiles make it a potential candidate for the advances of new therapies for necroptosis-associated neuroinflammatory disorders.