Resveratrol-delivery vehicle with anti-VEGF activity carried to human retinal pigmented epithelial cells exposed to high-glucose induced conditions

As an integrated approach to defeat diabetic retinopathy, a common complication of diabetes leading to vision loss, a delivery vehicle able to transport resveratrol (Rv) directly into retina pigmented epithelial D407 cells was designed. Rv, a molecule with known therapeutic potential, was successfully inserted into a microcapsule based on porous CaCO3 templates revealing an encapsulation efficiency of 96.8 +/- 4.0%. Four alternative layers of polyelectrolytes were deposited via electrostatic-driven layer-by-layer assembly approach on the template and covered by rhodamine 6G (Rh6G). The as-designed PMs-Rv-Rh6G microcapsules were internalized into D407 cells grown in normal and high glucose-induced inflammation conditions, being able to cross the cellular membrane and localize near the nucleus after 24 h treatment. The metabolic activity of D407 cells was not diminished by PMs-Rv-Rh6G even after 24 h treatment, meaning that the microcapsules do not exert any toxicity toward the cells, based on WST-1 and lactate dehydrogenase assays. Notably, the PMs-Rv-Rh6G treatment is able to inhibit the vascular endothelial growth factor (VEGF) protein, as was proved by the ELISA assay. Therefore, the proposed PMs-Rv-Rh6G microcapsules could be implemented as a potential self-reporting intraocular Rv-delivery vehicle with anti-VEGF activity in the management of diabetic retinopathy.