Oral PTP1B siRNA Delivery Using Milk-Derived Extracellular Vesicles for Alleviation of Acute Kidney Injury

Acute kidney injury (AKI), frequently caused by ischemia-reperfusion (IR) injury, remains a significant clinical challenge, with no effective therapeutic interventions. AKI is characterized by oxidative stress, endoplasmic reticulum (ER) stress, and inflammation, which exacerbates renal damage. Recently, protein tyrosine phosphatase 1B (PTP1B) has emerged as a therapeutic target in ischemic diseases due to its role in exacerbating ER stress and inflammation. In this study, we observed significant PTP1B overexpression in tissues from AKI patients and mouse models, linked to increased ER stress and Src-mediated inflammation. To explore the therapeutic potential of PTP1B inhibition, we delivered PTP1B-targeting siRNA (PTPi) using milk-derived extracellular vesicles (mEVs). PTPi-loaded mEVs (PTPi@mEVs) reduced PTP1B expression in proximal tubular cells, leading to decreased ER stress, Src activation, and inflammation. In the IR-AKI mice, PTPi@mEVs improved renal function, reduced cell death, and restored tight junction integrity in renal tissues. Notably, oral administration of PTPi@mEVs demonstrated substantial therapeutic effects, underscoring the potential of mEVs as a novel delivery system for siRNA therapies. These findings highlight the therapeutic potential of targeting PTP1B to modulate key pathological processes in AKI, including the ER stress-oxidative stress-inflammatory axis, demonstrating the efficacy of mEV-mediated PTPi delivery in reducing acute inflammation and renal dysfunction.