Evaluation of Curcumin-Loaded Nanoliposomes for the Treatment and Prevention of Age-Related Macular Degeneration

Abstract

Age-related macular degeneration (AMD), the most common cause of vision loss for people age 50 and over, is a disease characterized by the buildup of oxidative stress in the back of the eye. Current remedies are limited to intravitreal injections that only target the more severe ‘wet’ form; the common ‘dry’ form has no readily available pharmaceutical solution. Curcumin, a natural antioxidant found in the Indian spice turmeric, has shown potential in combating inflammatory diseases like AMD; however, the molecule also demonstrates poor bioavailability. This research aimed to create curcumin-loaded nanoliposomes (NLs) to be delivered noninvasively to potentially treat and prevent the onset of AMD. The 220 nm NLs were composed of phosphatidylcholine and cholesterol through vacuum evaporation, rehydration, and extrusion. Our curcuminloaded NLs were assessed using an in vitro oxidative stress model of ARPE-19 cells. MTT cell viability assay results show that the liposomal curcumin complex has been able to improve cell viability with respect to the untreated cells (28% more viable, p < 0.05), and cells that were damaged with peroxide (50% more viable, p < 0.05). As a preventative measure, the liposomal curcumin complex has been able to improve cell viability with respect to untreated cells (55% more viable, p < 0.05). Ex vivo modeling tested the permeability of the nanoliposomes to the posterior hemisphere of a porcine eye with a Franz diffusion cell apparatus. Qualitative fluorescence analysis shows that the nanoliposomes were able to permeate through different layers of the eye and reach the retina. In vitro studies with RPE cells show the treatment significantly reduces oxidative stress in cells while increasing cell viability, thus indicating that curcumin has potential to both treat and prevent AMD.