4th EVIta Symposium

Muscle-targeted delivery of Coenzyme Q10 via exosome-mimetic nanovesicles: Coenzyme Q (CoQ) is an endogenous lipophilic quinone, ubiquitous in biological membranes, with antioxidant and bioenergetic properties. CoQ deficiency can result from either a genetic defect or secondary deficiencies due to aging, oxidative stress, or drugs such as statins. CoQ supplementation represents a relevant strategy to mitigate CoQ deficit; however, numerous studies have demonstrated that the efficiency of dietary CoQ uptake is a limiting step. Exosomes, and more generally extracellular vesicles (EVs), can transfer biological information between cells, and have therefore recently been proposed as a new drug delivery system. In this study, we developed bioinspired, exosome-mimetic nanovesicles for delivering ubiquinone (CoQ10) to different cell types. Briefly, myocytes were lysed, and their membrane protein fraction was isolated, mixed with a mixture of choline-based phospholipids and ubiquinone, and finally subjected to serial extrusion to obtain CoQ10-loaded synthetic nanovesicles (Q10-SVs). The Q10-SVs have a similar diameter, zeta potential, and surface phenotype to muscle-derived exosomes; furthermore, HPLC quantification data showed CoQ10 loading efficiencies between 40-60%. The quantification of CoQ10 in the target cells provides an exciting perspective, where C2C12 and H9C2 cells incubated with loaded SVs can take up more CoQ10 than other cell lines, and in general, engineered nanovesicles allowed a more efficient assimilation of CoQ10 compared to bare CoQ10-loaded liposomes. Finally, the Q10-SV antioxidant activity was assessed using a wound-healing mitotimer assay. In H9C2 and C2C12 cells pre-incubated with Q10-SVs and then treated with hydrogen peroxide, almost complete migration was observed after eighteen hours of recovery, significantly improved over free or liposome-delivered CoQ10. Furthermore, using the Mitotimer technology, we demonstrated that Q10-SVs protect cardiomyocytes from mitochondrial oxidation and fragmentation. Collectively, these findings indicate that CoQ10 delivered via synthetic vesicles exhibits enhanced bioavailability and effectively shields myocytes and cardiomyocyte mitochondria from oxidative stress, highlighting the potential of synthetic nanovesicles as innovative exosome mimetics for efficient CoQ10 delivery.