DEF6 regulates renal ischemia reperfusion injury through suppressing the WWP2 mediated ubiquitination of PARP1

We confirmed that DEF6 was upregulated during RIRI and had a close correlation with RIRI-related inflammation and apoptosis. Moreover, inhibition of DEF6 could mitigate RIRI-induced kidney damage, inflammation, and apoptosis. Through our comprehensive mechanistic investigation, we revealed that DEF6 interacts with poly ADP-ribose polymerase 1 (PARP1) and suppresses the ubiquitination of PARP1. Inhibition of DEF6 resulted in reduced cleavage of PARP1, leading to a marked suppression of PARP1-mediated apoptosis activation. The aggravation effect on inflammation and apoptosis achieved through DEF6 was nullified by the inhibition of NF-kB and Bax/Bcl2 signaling activation through PARP1 deletion.