Seungjun Lee, Sang Heon Suh, Seong Kwon, Junghyun Kim, Sehyeon Park, Soo Wan Kim, Jae Young Lee
Background: Acute kidney injury (AKI) frequently progresses to chronic kidney disease (CKD) through the AKI-to-CKD transition; however, effective treatment strategies remain challenging due to the complex and multifactorial pathophysiology of this process.This study aims to develop a multifunctional nanoplatform for kidney-specific targeting, reactive oxygen species (ROS) scavenging, and anti-fibrotic drug delivery to mitigate AKI-to-CKD progression.Methods: Reduced graphene oxide (rGO) was conjugated with hyaluronic acid (HA) to form HA/rGO nanoparticles, enabling CD44-mediated renal targeting and ROS-responsive drug release.Paricalcitol, a hydrophobic anti-fibrotic agent, was loaded onto HA/rGO to form P/HA/rGO.The physicochemical characteristics, ROS-scavenging capacity, and oxidative stress-responsive drug release were evaluated.In vitro cytoprotection was assessed using HK-2 cells under oxidative stress.In vivo studies using ischemia/reperfusion (IR) injury mouse models assessed biodistribution, renal targeting, and therapeutic efficacy after systemic administration of P/HA/rGO.Results: HA/rGO nanoparticles demonstrated potent antioxidant activity and significantly protected HK-2 cells from ROS-induced cytotoxicity.P/HA/rGO exhibited a high paricalcitol loading efficiency (93%) and released 26% of the drug over 30 days under oxidative conditions.P/HA/rGO selectively accumulated in IR-injured kidneys via HA-CD44 interactions, decreased serum NGAL and cystatin C levels, and effectively attenuated tubular injury, fibrosis, inflammation, and apoptosis compared to vehicle-treated controls. Conclusion:The P/HA/rGO nanoplatform enables kidney-targeted delivery of paricalcitol with ROS-scavenging and ROS-responsive release properties, providing a promising therapeutic strategy to suppress the AKI-to-CKD transition via integrated targeting and microenvironment-responsive therapy.