A novel mitochondria-targeting tetrapeptide for subcellular delivery of nanoparticles

Mitochondrial dysfunction is associated with the emergence of several neurological and cardiovascular diseases. Hence, mitochondria-targeting delivery strategies are highly significant and critically needed. In this study, we developed a small library of peptides simulating the mitochondria-targeting peptide SS-31, a promising tetra-peptide with antioxidant character, and subsequently evaluated the toxicity, antioxidant ability and mitochondrial delivery of nanoparticles. Among the designed peptides, RF-2 ( d -Arg-Dmt-Arg-Phe-NH 2 ) showed controlled toxicity and excellent protection against gentamicin-induced hair cell damage, as compared with SS-31. More importantly, RF-2-modified PLGA nanoparticles demonstrated high colocalization with mitochondria and comparable specific subcellular accumulation, when compared with SS-31. Taken together, the obtained results supported RF-2 as a mitochondria-targeting peptide with high potential as a targeted carrier.