Abstract
Exosomes are cell derived and membrane-surrounded particles that deliver bioactive molecules to various cells. Their small size, low immunogenicity, extended blood circulation, and involvement in cellular communication make them a potentially effective drug carrier. Exosomes found in different biological fluids including mare’s milk, a traditional drink in central Asia. Therefore, the aim of this study is to compare exosomes isolation methodology and determine the stability of mare’s milk-derived exosomes as potential therapeutic carrier. Three extraction methods namely, immunoprecipitation, size exclusion chromatography, and total exosome isolation were compared in terms of exosome characteristics, purity, and content. The isolated exosomes then loaded with quercetin and their ability of increasing its bioavailability were tested in vitro and in vivo. Out of the three tested methods, total exosome isolation appeared to be the most efficient method that produced good quality exosomes, which were then loaded with quercetin and compared to free quercetin and exosomes only. Interestingly, exosomes loaded with 80µM quercetin significantly restored β-galactosidase activity and cellular viability in doxorubicin treated cells more than negative control and exosomes only, with a potency similar to that of 160µM free quercetin. Interestingly, aged model animals treated with exosomes loaded with quercetin showed significantly less frequent patterns of acute and subacute damage in the myocardium, kidneys, and liver compared to the untreated control group of aged models. The current study is a proof-of-concept that shows mare’s milk-derived exosomes are able to be absorbed by cells and animal tissues, which support their potential use as drug carrier.