Interruption of the visual cycle in a novel animal model induces progressive vision loss resembling Stargardts Disease.

Mutations in the gene ABCA4 coding for photoreceptor-specific ATP-binding cassette subfamily A member 4, are responsible for Stargardts Disease type 1 (STGD1), the most common form of inherited macular degeneration. STGD1 typically declares early in life and leads to severe visual handicap. Abca4 gene-deletion mouse models of STGD1 accumulate lipofuscin, a hallmark of the disease, but unlike the human disease show no or only moderate structural changes and no functional decline.

Iron overload and chelation modulates bisretinoid levels in the retina.

Aim: Iron dysregulation in conjunction with other disease processes may exacerbate retinal degeneration. We employed models of iron overload and iron chelation to explore the interactions between iron-catalyzed oxidation and photoreactive bisretinoid lipofuscin.

Methods: The mice were injected intravitreally with ferric ammonium citrate (FAC) or were treated using the iron chelator deferiprone (DFP) from birth to 2 months of age.

Near Infrared Autofluorescence Lifetime Imaging of Human Retinal Pigment Epithelium Using Adaptive Optics Scanning Light Ophthalmoscopy.

Purpose: To demonstrate the first near-infrared adaptive optics fluorescence lifetime imaging ophthalmoscopy (NIR-AOFLIO) measurements in vivo of the human retinal pigment epithelial (RPE) cellular mosaic and to visualize lifetime changes at different retinal eccentricities.

Methods: NIR reflectance and autofluorescence were captured using a custom adaptive optics scanning light ophthalmoscope in 10 healthy subjects (23-64 years old) at seven eccentricities and in two eyes with retinal abnormalities. Repeatability was assessed across two visits up to 8 weeks apart.

Microsomal triglyceride transfer protein is necessary to maintain lipid homeostasis and retinal function.

Lipid processing by the retinal pigment epithelium (RPE) is necessary to maintain retinal health and function. Dysregulation of retinal lipid homeostasis due to normal aging or age-related disease triggers lipid accumulation within the RPE, on Bruch's membrane (BrM), and in the subretinal space. In its role as a hub for lipid trafficking into and out of the neural retina, the RPE packages a significant amount of lipid into lipid droplets for storage and into apolipoprotein B (APOB)-containing lipoproteins (Blps) for export.