Extracellular Vesicle-Mediated Delivery of Antioxidant Enzymes: Emerging Insights and Translational Opportunities

Oxidative stress is a key contributor to the onset and progression of diverse pathological conditions, including metabolic dysfunction-associated steatotic liver disease (MASLD), neurodegeneration, cardiovascular disorders, and cancer. Conventional antioxidant therapies, such as small-molecule scavengers or systemic enzyme administration, are limited by poor stability, inefficient delivery, and off-target effects. Extracellular vesicles (EVs), particularly exosomes, are increasingly recognized as natural carriers of antioxidant enzymes (AOEs), including catalase, superoxide dismutases, glutathione peroxidases, peroxiredoxins, and thioredoxin. These vesicles not only protect enzymes from degradation but also enable targeted delivery to recipient cells, where they can actively modulate redox homeostasis. In this review, we summarize current evidence for AOEs as bona fide EV cargo, outline mechanisms that govern their selective packaging and transfer, and highlight their roles in intercellular communication under physiological and pathological conditions. We also discuss emerging therapeutic applications of both natural and engineered EVs for redox modulation, along with the challenges of quantifying enzymatic activity, ensuring reproducibility, and scaling clinical translation. By integrating insights from cell biology, redox signaling, and translational research, we propose that EV-mediated AOE delivery represents a promising next-generation strategy for combating oxidative stress-related diseases.