Artificial oil body as a potential oral administration system in zebrafish

Abstract

Zebrafish are well recognized as an excellent vertebrate model which, in particular, facilitates the rapid investigation of drug effects on cancers. A prerequisite for this anti-cancer study appears to have a non-invasive and effecicve method for admininstration of drugs. In this study, we explored the potential of artificial oil bodies (AOBs) for the oral administration of a hydrophobic agent in adult zebrafish. A hydrophobic dye was employed for illustration, and AOBs were assembled with phospholipids, a storage protein, and an equal volume of olive oil and brine shrimp oil. Consequently, more than 90% of the dye was encapsulated in AOBs which exhibited a prolonged release profile for the dye cargo. The dye-loaded AOBs collected as an oil cake remained integral within 30 min in the aquatic solution while it was completely consumed by one zebrafish in a few seconds. As revealed by the fluorescence microscopy and frozen section, the fluorescence signal was detected in the zebrafish intestinal tract 2 h after the oral administration. The dye cargo was completely absorbed in 12 h and almost no trace was left in zebrafish feces. Overall, the AOBs system is biocompatible and shows promise in the oral administration of chemical entities for zebrafish.