Acute kidney injury (AKI) is a clinical syndrome that is defined as a sudden decline in renal function and characterized by
inflammation and programmed cell death of renal tubular epithelial cells. Necroptosis is a form of regulated cell death that requires activation of receptor interacting
protein kinase 3 (RIPK3) and its phosphorylation of the substrate MLKL. RIPK3 plays an important role in
acute kidney injury, and hence developing its inhibitors is considered as one of the promising strategies aimed at prevention and treatment of AKI. Recently, we discovered
AZD5423 as a novel potent RIPK3 inhibitor using a computer-aided hybrid virtual screening strategy according to three-dimensional structure of RIPK3. Our findings revealed that
AZD5423 strongly inhibits activation of RIPK3, and MLKL phosphorylation upon
cisplatin-,
hypoxia/reoxygenation (H/R)- and TNF-α stimuli as compared with
GSK872, which is a previously identified RIPK3 inhibitor. Importantly,
AZD5423 exerts effective protection against
cisplatin- and
ischemia/reperfusion (I/R)-induced AKI mouse model. The results of cellular thermal shift assay and experiments in RIPK3 knockout cells indicated that
AZD5423 could directly target RIPK3 to inhibit RIPK3
kinase activity. Mechanistically, the docking of
AZD5423 and RIPK3 suggested that the
kinase domain of RIPK3 for Lys50, Arg313, Lys29, Arg37 might form hydrogen bonds with
AZD5423. Site-directed mutagenesis further revealed that
AZD5423 reduces injury response via interacting with the key RIPK3
amino acid residues of Lys50 and Arg313. In conclusion, our study has demonstrated that
AZD5423 may serve as a potent inhibitor of RIPK3
kinase and a promising clinical candidate for AKI treatment.