Human Platelet-derived Lysates and Extracellular Vesicles Restore Mitochondrial Function and Redox Balance in Neuronal Models

Abstract

Platelet-derived biomaterials are emerging as promising cell-free therapeutic platforms for regenerative medicine and neurorestoration. Among them, human platelet pellet lysates (HPPL) and platelet-derived extracellular vesicles (PEVs), prepared from clinical-grade allogeneic platelet concentrates, provide two complementary biomaterial formats: a soluble trophic factor-rich lysate and a vesicular formulation enriched in bioactive cargo. Because mitochondrial dysfunction and redox imbalance are hallmarks of neurodegeneration, we investigated whether these platelet-derived biomaterials could protect against rotenone-induced mitochondrial injury. HPPL and PEVs were bioprocessed from clinical-grade platelet concentrates and characterized for protein content, antioxidant capacity, vesicle morphology, size distribution, concentration and platelet and EVs markers. Differentiated N2A and SH-SY5Y neuronal cells were pretreated with 5% v/v HPPL or PEVs before rotenone (5 {micro}M) exposure, while zebrafish embryos received 20 g/mL HPPL or PEVs before rotenone (200 nM) challenge. Both biomaterials restored ATP production, reduced reactive oxygen species (ROS), preserved mitochondrial membrane potential and ultrastructure, and improved neuronal survival. They also normalized key markers of mitochondrial biogenesis and dynamics, including peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1), mitofusin-1 (MFN1), and dynamin-related protein 1 (DRP1). Proteomic analyses further showed enrichment of mitochondrial-associated antioxidant and metabolic proteins in HPPL and PEVs, and revealed restoration of oxidative phosphorylation, tricarboxylic acid cycle-related pathways, antioxidant defense, and mitochondrial dynamics in rotenone-injured cells following pretreatment. In zebrafish embryos, both biomaterials improved survival and hatching, reduced developmental abnormalities and oxidative stress, and preserved mitochondrial ultrastructure. These findings identify HPPL and PEVs as platelet-derived biomaterials with complementary mitochondrial protective activity, supporting their development as scalable cell-free biotherapeutic platforms for neurodegenerative disorders.