Application of plant-derived exosome-like nanoparticles in drug delivery

Exosomes are one type of extracellular vesicles with size ranging from 30 to 150 nm, which are involved in intercellular communication by transporting specific proteins, nucleic acids, and low molecular weight metabolites. The size and competence of exosomes to transfer biological materials to recipient cells have made them suitable for biomedical use. Therefore, exosomes have been studied as drug delivery systems for various diseases due to low immunogenicity, preferred tumor homing, innate and acquired targetability, and stability. They are secreted by almost all cells from multivesicular endosomes and retrieved in all body fluids including bile, saliva, blood, lymph, urine, cerebrospinal fluid, milk, and etc. Plants' organs also secrete exosomes (Plant-derived exosome-like nanoparticles (PELNs)) which have been considered as an economical and affordable source of production. PELNs are pharmacologically rich in active molecules because of owning unique compositional and morphological features and they can be used as natural nano-carrier for transporting exogenous molecules. In this review, the bio-component and the applications of PELNs as drug delivery systems in neural disorders, tumor-targeted delivery, and gene delivery have been reviewed in different plants such as aloe, turmeric, ginger, lemon, grapefruit, grape, and strawberry.