Anti-metastatic effect of diallyl trisulfide-exosome in mouse melanoma / 药学学报

ABSTRACT

This study aimed to prepare an anti-metastatic diallyl trisulfide-exosome (DATS-Exo) drug delivery system. Exosomes in the supernatants of lung metastasis mouse melanoma B16BL6 cell line culture were extracted by ultracentrifugation. The quantity of exosomes was determined by transmission electron microscopy (TEM), Malvern particle size meter, and BCA assay. Expression levels of exosome-specific biomarkers CD9, TSG101, Flotillin 1 and lung organotropic biomarker α6 were detected by Western blot. The sonication method was used to load DATS into exosomes. The uptake of exosomes by B16BL6 cells and lung tissue was observed by laser confocal microscopy. Wound healing assay was used to evaluate the anti-migration effect of DATS-Exo in vitro. Experimental lung metastasis model was established to evaluate the anti-metastasis effect of DATS-Exo in vivo. Animal experiments have been approved by the Ethics Committee of Nanjing University of Chinese Medicine. The results showed that the particle size of DATS-Exo was 112.3 ± 1.98 nm, polydispersity index (PDI) was 0.24 ± 0.08, zeta potential was -24.33 ± 4.11 mV, and the particles have classic tea tray-like membrane structure under TEM. The protein concentration of DATS-Exo was measured to be 1 312.33 ± 6.27 μg·mL-1. The drug loading rate was about 0.33% ± 0.02%. The exosomes could be taken up by B16BL6 cells and the lung tissue. Compared with the free DATS group, DATS-Exo had a better inhibitory effect on tumor metastasis in vitro and in vivo. Taken together, these results indicate that exosomes derived from the lung metastasis tumor cells have lung organotropic characteristic and drug-loading properties. Using these kind of exosomes as carrier for anti-tumor drug delivery can be a novel and effective strategy of anti-metastatic therapy.