Stem cell-derived extracellular vesicles enriched with miR-22-3p for cataract treatment – Molecular mechanisms and therapeutic potential: A review

Cataracts, characterized by progressive lens opacification, affect a significant number of individuals globally, particularly the elderly and those with systemic diseases. Research on the pathogenesis of visual impairments has identified alterations in crystalline proteins, primarily driven by inflammation, apoptosis, oxidative stress, and fibrosis in lens epithelial cells, as the primary mechanisms contributing to cataract development. Current treatment options, including surgical lens implantation and stem cell therapy, have notable limitations, highlighting the need for alternative non-invasive therapies. Stem cell-derived extracellular vesicles (SC-EVs) have emerged as a novel therapeutic approach for various diseases. This review aims to comprehensively analyze the literature regarding the therapeutic potential of SC-EVs in cataract treatment, particularly when enriched with miR-22-3p. A literature search was conducted focusing on the molecular mechanisms of miR-22-3p in lens epithelial cells and cataract models, discussing its regulatory pathways in retinal and optic nerve injuries, as well as the advantages of utilizing SC-EVs as nanocarriers for targeted therapy. Studies indicate that miR-22-3p can inhibit crystalline remodeling by modulating gene expression and regulating apoptosis, fibrosis, oxidative stress, and inflammation. Consequently, it plays a role in the signaling pathways associated with cataracts and may also exhibit neuroprotective effects in neurons and retinal ganglion cells. By integrating current insights from research on cell-free EV therapies and the molecular mechanisms of miR-22-3p in cataract pathology, this review underscores the potential of miR-22-3p-enriched SC-EVs as a promising therapeutic option for cataracts. However, this hypothesis necessitates rigorous preclinical and clinical validation.