Enhanced oral bioavailability and in vitro evaluation of cannabidiol camel milk-derived exosome formulation in resistant MDA-MB-231 and MDA-MB-468 breast cancer cells

The potential of camel milk-derived exosomes (CMDE) to enhance the bioavailability of Cannabidiol (CBD) was investigated. CBD-CMDE formulation was prepared using an established procedure and its particle size was 138.4 ± 4.37 nm, and CBD entrapment efficiency of 56.56 ± 4.26 %. In-vitro release studies showed release of 78.27 ± 5.37 % and 46.42 ± 4.75 % CBD from CMDE and control CBD formulation respectively in pH 6.8 at 24 hr. The apparent permeability (Papp) of CBD-CMDE was found to be enhanced by 3.95-fold with Papp of 22.9*10^-6 ± 0.34 cm/sec as compared to control CBD formulation with Papp of 5.8*10^-6 ± 0.65 cm/sec in MDCK cells. CBD-CMDE was found to be more potent than CBD in 2D cytotoxicity assay with IC₅₀ values of 3.6 ± 0.54 µM, 3.88 ± 0.54 µM and 7.53 ± 0.59 µM, 7.53 ± 0.59 µM against Doxorubicin (DOX) resistant MDA-MB-231 and Rapamycin (RM) resistant MDA-MB-468 breast cancer cells respectively. Moreover, 3D spheroids assay results demonstrated CBD-CMDE with IC₅₀ values of 14 ± 0.85 µM, 15 ± 0.07 µM as compared to CBD alone with IC₅₀ values of 25 ± 0.93 µM, 34.7 ± 0.08 µM in MDA-MB-231 DOX RT cells and MDA-MB-468 RM RT cells respectively. In-vivo PK studies showed enhanced bioavailability of CBD from CBD-exosomes with AUC_(0-24h) of 1350.56 ± 187.50 h.ng/mL as compared to CBD control formulation with AUC_(0-24h) of 351.95 ± 39.10 h.ng/mL with a single oral dose of 12 mg/kg. The data indicate that CMDE significantly improved the oral bioavailability of CBD. Overall, CMDE can be used to enhance the oral absorption of poorly bioavailable APIs.