Reactive Oxygen Species- and Cell-Free DNA-Scavenging Mn3O4 Nanozymes for Acute Kidney Injury Therapy

Reactive oxygen species (ROS) scavenging therapy toward acute kidney injury (AKI) is promising, but no effective ROS scavenging drug has been developed yet. Moreover, cell-free DNA (cfDNA) is also involved in AKI, but the corresponding therapies have not been well developed. To tackle these challenges, Mn3O4 nanoflowers (Nfs) possessing both ROS and cfDNA scavenging activities were developed for better AKI protection as follows. First, Mn3O4 Nfs could protect HK2 cells through cascade ROS scavenging (dismutating ·O2– into H2O2 by superoxide dismutase-like activity and then decomposing H2O2 by catalase-like activity). Second, Mn3O4 Nfs could efficiently adsorb cfDNA and then decrease the inflammation caused by cfDNA. Combined, remarkable therapeutic efficacy was achieved in both cisplatin-induced and ischemia–reperfusion AKI murine models. Furthermore, Mn3O4 Nfs could be used for the T1-MRI real-time imaging of AKI. This study not only offered a promising treatment for AKI but also showed the translational potential of nanozymes.