Cigarette Smoke–Related Oxidants and the Development of Sub-RPE Deposits in an Experimental Animal Model of Dry AMD

Abstract

Exposure to cigarette smoke or the smoke-related redox molecule, HQ, results in the formation of sub-RPE deposits, thickening of Bruch's membrane, and accumulation of deposits within Bruch's membrane. Smoke-related oxidants may be another oxidative injury stimulus to the choriocapillaris and RPE, and may explain the association between cigarette smoking and early AMD.

Avaliação das alterações precoces na coróide e esclera ocorridas em coelhos hipercolesterolêmicos: estudo histológico e histomorfométrico

“…Acredita-se que a fase inicial da DMRI possa estar relacionada com o acúmulo de depósitos ricos em lipídios abaixo do epitélio pigmentário retiniano (EPR) (1)(2) . Estes depósitos teriam origem no mau funcionamento das células do EPR (10) que enviaria restos celulares maiores que o normal, provenientes da fagocitose das extremidades dos fotorreceptores, para a coriocapilar.…”

“…Estudos epidemiológicos têm focado a hipótese vascular ao analisar os fatores clássicos de risco para a doença cardiovascular, tais como pressão arterial, colesterol sérico, tabagismo e consequentemente processo aterosclerótico como infarto do miocárdio. Os resultados têm sido incon-clusivos, exceto no quesito tabagismo (2) . Recente estudo demonstrou que níveis altos de HDL preveniriam a DMRI tardia enquanto alto nível de colesterol total proporcionaria risco maior para DMRI tardia e atrofia geográfica (3) .…”

Vascular endothelial growth factor in eye disease

“…Oxidants have been reported to increase the deposition of oxidized proteins or other compounds in Bruch's membrane (Espinosa-Heidmann et al, 2006). In addition, photo-oxidation compounds of lipofuscin (i.e., A2E, a pigment that increases with increasing age) in the outer retina can activate the complement pathways (Zhou et al, 2006) and may lead to CNV and VEGF release as discussed in the previous section.…”

“…Oxidative stress and VEGF expression in AMD-Oxidative stress has been proposed in AMD through several mechanisms (Cai et al, 2000;Spaide et al, 2003), including blue light-induced photochemically released oxidants that damage photoreceptors (Margrain et al, 2004), cigarette smoke-related oxidants such as hydroquinone that alter Bruch's membrane (Espinosa-Heidmann et al, 2006), iron induced oxidative damage to the outer retina (Dunaief, 2006), and possibly through AGE within Bruch's membrane (Tian et al, 2005). Oxidants have been reported to increase the deposition of oxidized proteins or other compounds in Bruch's membrane (Espinosa-Heidmann et al, 2006).…”

Looking beyond Lucentis on the management of macular degeneration

“…Lesions similar to those in the aging retina develop in the eyes of mice that are exposed to cigarette smoke or dietary hydroquinone. 28 …”