Plant-derived exosome-like nanoparticles and their therapeutic activities

Nanotechnologies have been successfully applied to the treatment of various diseases.Plant-derived exosome-like nanoparticles (PENs) are expected to become effective therapeutic modalities for treating disease or in drug-delivery. PENs are minimally cytotoxic to healthy tissues, with which they show excellent biocompatibility, and are biased towards tumors by targeting specific tissues through special endocytosis mechanisms. Thus, the use of these PENs may expand the scope of drug therapies while reducing the off-target effects.In this review, we summarize the fundamental features and bioactivities of PENs extracted from the grape, grapefruit, ginger, lemon, and broccoli and discuss the applications of these particles as therapeutics and nanocarriers.

Standardization of Sampling for Isolation of Exosome-Like Small-Extracellular Vesicles from Peripheral Blood from Reproductive-Aged Women

Exosome-like small-extracellular vesicles (sEVs) are extracellular vesicles that act in intercellular communication and are involved in several biologic and pathologic processes. While sEVs increase the stability of their cargo molecules, there is still a need for standardization of sampling and isolation of these microvesicles. We aimed to determine the best sampling method for isolation of sEVs from peripheral blood from reproductive-aged women. Material and Methods: We included samples of plasma from our biobank collected in 2014 by venipuncture in heparin tubes and stored at -80°C. We also included blood samples collected in heparin tubes and Ethylenediamine tetraacetic acid (EDTA) tubes and stored at -80°C for one to two weeks prior processing. All blood samples were collected from the same nine reproductive-aged female volunteers. sEVs were isolated from plasma by ultracentrifugation and filtration and indirectly quantified using Pierce BCA Protein Assay kit. Transmission electron microscopy (TEM) and Nano Tracking Analysis (NTA) were performed to confirm the isolation of sEVs. Results and Discussion: TEM and NTA confirmed the isolation of sEVs. Protein concentration of short-time stored heparin samples was not statistically different from long-time stored heparin samples (1847.2 ± 651.4 vs. 2363.2 ± 1025.1, p = 0.14). There was no difference between heparin and EDTA plasma samples recently collected (2363.2 ± 1025.1 vs. 2044.8 ± 653.2, p = 0.44). In conclusion, blood samples may be collected using heparin or EDTA for isolation of sEVs. Long-time stored plasma samples maintain sEVs integrity and may be used, especially in comparative studies.

Natural exosome-like nanovesicles from edible tea flowers suppress metastatic breast cancer via ROS generation and microbiota modulation

Although several artificial nanotherapeutics have been approved for practical treatment of metastatic breast cancer,their inefficient therapeutic outcomes,serious adverse effects,and high cost of mass production remain crucial challenges.Herein,we developed an alternative strategy to specifically trigger apoptosis of breast tumors and inhibit their lung metastasis by using natural nanovehicles from tea flowers(TFENs).These nanovehicles had desirable particle sizes(131 nm),exosome-like morphology,and negative zeta potentials.Furthermore,TFENs were found to contain large amounts of polyphenols,flavonoids,functional proteins,and lipids.Cell experiments revealed that TFENs showed strong cytotoxicities against cancer cells due to the stimulation of reactive oxygen species(ROS)amplification.The increased intracellular ROS amounts could not only trigger mitochondrial damage,but also arrest cell cycle,resulting in the in vitro anti-proliferation,anti-migration,and anti-invasion activities against breast cancer cells.Further mice investigations demonstrated that TFENs after intravenous(i.v.)injection or oral administration could accumulate in breast tumors and lung metastatic sites,inhibit the growth and metastasis of breast cancer,and modulate gut microbiota.This study brings new insights to the green production of natural exosome-like nanoplatform for the inhibition of breast cancer and its lung metastasis via i.v.and oral routes.

Isolation of cabbage exosome-like nanovesicles and investigation of their biological activities in human cells

There are extensive studies on the applications of extracellular vesicles(EVs)produced in cell culture for therapeutic drug development.However,large quantities of EVs are needed for in vivo applications,which requires high production costs and time.Thus,the development of new EV sources is essential to facilitate their use.Accordingly,plant-derived exosome-like nanovesicles are an emerging alternative for culture-derived EVs.Until now,however,few studies have explored their biological functions and uses.Therefore,it is necessary to elucidate biological activities of plant-derived exosome-like nanovesicles and harness vesicles for biomedical applications.Herein,cabbage and red cabbage were used as nanovesicle sources owing to their easy cultivation.First,an efficient method for nanovesicle isolation from cabbage(Cabex)and red cabbage(Rabex)was developed.Furthermore,isolated nanovesicles were characterized,and their biological functions were assessed.Both Cabex and Rabex promoted mammalian cell proliferation and,interestingly,suppressed inflammation in immune cells and apoptosis in human keratinocytes and fibroblasts.Finally,therapeutic drugs were encapsulated in Cabex or Rabex and successfully delivered to human cells,demonstrating the potential of these vesicles as alternative drug delivery vehicles.Overall,the current results provide strong evidence for the wide application of Cabex and Rabex as novel therapeutic biomaterials.