Delivering drugs to tubular cells and organelles: the application of nanodrugs in acute kidney injury

Acute kidney injury (AKI) is a common clinical syndrome with limited treatment options and high mortality rates. Proximal tubular epithelial cells (PTECs) play a key role in AKI progression. Subcellular dysfunctions, including mitochondrial, nuclear, endoplasmic reticulum and lysosomal dysfunctions, are extensively studied in PTECs. These studies have led to the development of potential therapeutic drugs. However, clinical development of those drugs faces challenges such as low solubility, short circulation time and severe systemic side effects. Nanotechnology provides a promising solution by improving drug properties through nanocrystallization and enabling targeted delivery to specific sites. This review summarizes advancements and limitations of nanoparticle-based drug-delivery systems in targeting PTECs and subcellular organelles, particularly mitochondria, for AKI treatment.