Exosomal formulation of anthocyanidins against multiple cancer types

• Milk exosomes can serve as a vehicle to berry bioactive, anthocyanidins (Anthos).
• Anthocyanidins were stable in exosomal formulation for weeks.
• Exosomes alone exhibited anti-proliferative and anti-inflammatory effects.
• Exosomal formulation of Anthos provide enhanced activity compared with free Anthos.
• Oral delivery of ExoAnthos caused significant inhibition of lung tumor xenografts.

Over the last two decades, berries and berry bioactives, particularly anthocyanins and their aglycones anthocyanidins (Anthos) have demonstrated excellent anti-oxidant, anti-proliferative, apoptotic and anti-inflammatory properties. However, their physicochemical and pharmacokinetic limitations such as, low permeability, and poor oral bioavailability are considered as unfavorable properties for development as drugs. Therefore there is a need to develop systems for efficient systemic delivery and robust bioavailability. In this study we prepared nano-formulation of bilberry-derived Anthos using exosomes harvested from raw bovine milk. Exosomal formulation of Anthos enhanced antiproliferative and anti-inflammatory effects compared with the free Anthos against various cancer cells in vitro. Our data also showed significantly enhanced therapeutic response of exosomal-Anthos formulation compared with the free Anthos against lung cancer tumor xenograft in nude mice. The Anthos showed no signs of gross or systemic toxicity in wild-type mice. Thus, exosomes provide an effective alternative for oral delivery of Anthos that is efficacious, cost-effective, and safe, and this regimen can be developed as a non-toxic, widely applicable therapeutic agent.