Oxidative Medicine and Cellular Longevity / 2018 / Article / Fig 2

Review Article

Age-Related Macular Degeneration: New Paradigms for Treatment and Management of AMD

Figure 2

A diagram illustrating the anatomical differences between RPE and BM on dry AMD (a) and wet AMD (b). Early AMD involves the accumulation of drusen and beta-amyloid peptides in the subretinal space. This might progress to dry AMD (a), which is characterized by inflammation and photoreceptor degeneration, caused in part by oxidative stress; resveratrol and alpha-lipoic acid prevent these effects. Autophagy induction by trehalose might help to eliminate intracellular components that abnormally accumulate intracellularly avoiding the following extracellular accumulation of toxic peptides, like beta-amyloid and lipids. Another strategy for the physiological recovery in AMD is the administration of induced pluripotent stem cells (iPSCs). Wet AMD (b) in which neovascularization from invading choroid vessels and the Bruch’s membrane (BM) rupture cause photoreceptor damage. Besides, neovascularization of the retina ruptures the Bruch’s membrane, which damages the macula and results in blurry or spotty vision. Anoxia and hypoxia-inducible factor 1 (HIF-1) induce the expression of VEGF-A, and as a possible treatment, thrombospondin-1 (TSP-1) protein might be used to block VEGF-A and metalloproteinases 2 and 9 (MMP-2 and MMP-9). Additionally, ranibizumab, aflibercept, bevacizumab, and bevasiranib could be used to block the angiogenic effects of VEGF on both cases.
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