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1.
Curr Eye Res ; 45(11): 1390-1394, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32202447

RESUMEN

Purpose: A hallmark of age-related macular degeneration is the accumulation of deposits of lipids and proteins, called drusen, in Bruch's membrane. Several culture models of retinal pigment epithelia (RPE) develop drusen-like deposits. We examined whether prolonged culture of RPE with a retina-like tissue affected the number or size of these deposits. Methods: RPE and retinal progenitor cells (RPC) were differentiated from induced pluripotent stem cells derived from fetal tissue and maintained in serum-free medium containing the B27 supplement. RPE was cultured on Transwell filter inserts, and RPC were cultured on a planar matrix composed of gelatin, hyaluronic acid, and chondroitin sulfate. After seeding the filter, RPC were layered on top of the RPE. RPE ± RPC were cultured for six months. The function of RPE tight junctions was assessed by the transepithelial electrical resistance. Cultures were stained for actin, neutral lipids, APOE, TIMP3, vitronectin, and calcium deposits. Morphometric analysis was used to determine the number and volume of the "druse". Results: After six months, the TER was greater for the co-cultures (304 ± 11 Ω× cm2 vs 243 ± 7 Ω× cm2, p < .01). RPE formed mounds of druse-like deposits that contained, vitronectin, APOE, TIMP3 and calcium deposits, but lipids were undetected. The mounds overlay areas of the filter where no lipid was detected in the pores, and the RPE overlying the mounds was often thin. The number of "druse"/100,000 µm2 was 5.0 ± 0.4 (co-cultures) vs 2.3 ± 0.1 (monocultures) (p < .05). The total volume of "drusen"/100,000 µm3 was 15,133 ± 1544 (co-cultures) vs 5,993 ± 872 (monocultures) (p < .05). There was no statistical difference between the size-distribution of druse-like particles formed by each culture. Conclusions: Covering the apical membrane of RPE with a thick tissue increased the number of druse-like deposits. The apparent size limitation of the deposits may reflect the apparent interruption of the of lipid cycle found at the basal membrane of the RPE.


Asunto(s)
Drusas Retinianas/patología , Epitelio Pigmentado de la Retina/patología , Actinas/metabolismo , Apolipoproteínas E/metabolismo , Calcio/metabolismo , Técnicas de Cultivo de Célula , Línea Celular , Proliferación Celular/fisiología , Técnicas de Cocultivo , Medio de Cultivo Libre de Suero , Impedancia Eléctrica , Humanos , Células Madre Pluripotentes Inducidas/citología , Metabolismo de los Lípidos/fisiología , Drusas Retinianas/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Células Madre/citología , Uniones Estrechas/fisiología , Inhibidor Tisular de Metaloproteinasa-3/metabolismo , Vitronectina/metabolismo
2.
Retina ; 40(8): 1471-1482, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31404033

RESUMEN

PURPOSE: The LIGHTSITE I study investigated the efficacy and safety of photobiomodulation (PBM) treatment in subjects with dry age-related macular degeneration. METHODS: Thirty subjects (46 eyes) were treated with the Valeda Light Delivery System, wherein subjects underwent two series of treatments (3× per week for 3-4 weeks) over 1 year. Outcome measures included best-corrected visual acuity, contrast sensitivity, microperimetry, central drusen volume and drusen thickness, and quality of life assessments. RESULTS: Photobiomodulation-treated subjects showed a best-corrected visual acuity mean letter score gain of 4 letters immediately after each treatment series at Month 1 (M1) and Month 7 (M7). Approximately 50% of PBM-treated subjects showed improvement of ≥5 letters versus 13.6% in sham-treated subjects at M1. High responding subjects (≥5-letter improvement) in the PBM-treated group showed a gain of 8 letters after initial treatment (P < 0.01) and exhibited earlier stages of age-related macular degeneration disease. Statistically significant improvements in contrast sensitivity, central drusen volume, central drusen thickness, and quality of life were observed (P < 0.05). No device-related adverse events were reported. CONCLUSION: Photobiomodulation treatment statistically improved clinical and anatomical outcomes with more robust benefits observed in subjects with earlier stages of dry age-related macular degeneration. Repeated PBM treatments are necessary to maintain benefits. These pilot findings support previous reports and suggest the utility of PBM as a safe and effective therapy in subjects with dry age-related macular degeneration.


Asunto(s)
Atrofia Geográfica/radioterapia , Terapia por Luz de Baja Intensidad , Anciano , Anciano de 80 o más Años , Sensibilidad de Contraste/fisiología , Método Doble Ciego , Femenino , Atrofia Geográfica/diagnóstico , Atrofia Geográfica/fisiopatología , Atrofia Geográfica/psicología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Calidad de Vida/psicología , Drusas Retinianas/patología , Encuestas y Cuestionarios , Resultado del Tratamiento , Agudeza Visual/fisiología , Pruebas del Campo Visual , Campos Visuales/fisiología
3.
EBioMedicine ; 5: 198-203, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27077128

RESUMEN

IMPORTANCE: Age-related macular degeneration (AMD) remains the leading cause of blindness in developed countries, and affects more than 150 million worldwide. Despite effective anti-angiogenic therapies for the less prevalent neovascular form of AMD, treatments are lacking for the more prevalent dry form. Similarities in risk factors and pathogenesis between AMD and atherosclerosis have led investigators to study the effects of statins on AMD incidence and progression with mixed results. A limitation of these studies has been the heterogeneity of AMD disease and the lack of standardization in statin dosage. OBJECTIVE: We were interested in studying the effects of high-dose statins, similar to those showing regression of atherosclerotic plaques, in AMD. DESIGN: Pilot multicenter open-label prospective clinical study of 26 patients with diagnosis of AMD and the presence of many large, soft drusenoid deposits. Patients received 80 mg of atorvastatin daily and were monitored at baseline and every 3 months with complete ophthalmologic exam, best corrected visual acuity (VA), fundus photographs, optical coherence tomography (OCT), and blood work (AST, ALT, CPK, total cholesterol, TSH, creatinine, as well as a pregnancy test for premenopausal women). RESULTS: Twenty-three subjects completed a minimum follow-up of 12 months. High-dose atorvastatin resulted in regression of drusen deposits associated with vision gain (+ 3.3 letters, p = 0.06) in 10 patients. No subjects progressed to advanced neovascular AMD. CONCLUSIONS: High-dose statins may result in resolution of drusenoid pigment epithelial detachments (PEDs) and improvement in VA, without atrophy or neovascularization in a high-risk subgroup of AMD patients. Confirmation from larger studies is warranted.


Asunto(s)
Atorvastatina/administración & dosificación , Degeneración Macular/tratamiento farmacológico , Drusas Retinianas/tratamiento farmacológico , Epitelio Pigmentado de la Retina/efectos de los fármacos , Anciano , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/patología , Femenino , Humanos , Degeneración Macular/sangre , Degeneración Macular/patología , Masculino , Persona de Mediana Edad , Embarazo , Estudios Prospectivos , Desprendimiento de Retina , Drusas Retinianas/sangre , Drusas Retinianas/patología , Epitelio Pigmentado de la Retina/patología , Factores de Riesgo , Tomografía de Coherencia Óptica , Agudeza Visual/efectos de los fármacos
5.
Optom Vis Sci ; 88(2): 257-62, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21169874

RESUMEN

PURPOSE: Goji berry (Lycium barbarum L.) is purported to benefit vision because of its high antioxidant (especially zeaxanthin) content, although this effect has not been demonstrated in high-quality human studies. The purpose of this study was to evaluate the effects of daily supplementation with a proprietary milk-based formulation of goji berry, Lacto-Wolfberry (LWB), on macular characteristics and plasma zeaxanthin and antioxidant capacity levels in elderly subjects. METHODS: This was a double-masked, randomized, placebo-controlled trial in healthy elderly subjects (range, 65 to 70 years) receiving 13.7 g/d of LWB (n = 75) or placebo (n = 75) for 90 days. Subjects underwent direct ophthalmic examination to assess pigmentation and soft drusen count in the macula and a blood draw to measure plasma zeaxanthin level and total antioxidant capacity. RESULTS: The placebo group demonstrated hypopigmentation and soft drusen accumulation in the macula, whereas the LWB group remained stable. Both plasma zeaxanthin level and antioxidant capacity increased significantly in the LWB group, by 26% and 57%, respectively, but did not change in the placebo group. No product-related adverse events were reported in either group. CONCLUSIONS: Overall, daily dietary supplementation with goji berry for 90 days increases plasma zeaxanthin and antioxidant levels as well as protects from hypopigmentation and soft drusen accumulation in the macula of elderly subjects. However, the mechanism of action is unclear, given the lack of relationship between change in plasma zeaxanthin and change in macular characteristics.


Asunto(s)
Antioxidantes/metabolismo , Suplementos Dietéticos , Lycium , Mácula Lútea/efectos de los fármacos , Degeneración Macular/prevención & control , Preparaciones de Plantas/farmacología , Xantófilas/sangre , Anciano , Método Doble Ciego , Femenino , Humanos , Lycium/efectos adversos , Mácula Lútea/fisiopatología , Degeneración Macular/etiología , Masculino , Pigmentación/efectos de los fármacos , Preparaciones de Plantas/efectos adversos , Estudios Prospectivos , Drusas Retinianas/patología , Factores de Riesgo , Zeaxantinas
6.
J Fr Ophtalmol ; 33(4): 234-40, 2010 Apr.
Artículo en Francés | MEDLINE | ID: mdl-20223556

RESUMEN

INTRODUCTION: Low levels of lutein and zeaxanthin in blood or food are associated with an increased risk of age-related macular degeneration (AMD). These molecules, provided by food, form the macular pigment. PATIENTS AND METHODS: Patients included in this pilot study where categorized into four groups : (1) < 50 years with drusen, (2) > or = 50 years without drusen, (3) > or = 50 years with drusen, and (4) > or = 50 years with drusen and neovascularization. During consultation, macular pigment optical density was measured and information on pathology and eating habits were collected. RESULTS: Assessment of macular pigment optical density considering eating habits and groups showed that it was lower in group 1 patients when they ate less than five portions of fruits and vegetables per day and less than two portions of cabbage, broccoli, pepper, corn, or spinach a week. In groups 3 and 4, food supplement intake was related to an increase in optical density. Food supplements were consumed by 58.5 % of patients in group 4. CONCLUSION: Analysis of mean optical density measured by the MPS 9000 QuantifEYE considering eating habits confirmed the impact of food supplement intake on optical density, especially in patients > or = 50 years with drusen and with or without neovascularization.


Asunto(s)
Conducta Alimentaria , Mácula Lútea/patología , Epitelio Pigmentado de la Retina/patología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Brassica , Capsicum , Suplementos Dietéticos , Femenino , Frutas , Humanos , Luteína/administración & dosificación , Degeneración Macular/patología , Masculino , Persona de Mediana Edad , Proyectos Piloto , Drusas Retinianas/patología , Neovascularización Retiniana/patología , Factores de Riesgo , Spinacia oleracea , Verduras , Xantófilas/administración & dosificación , Adulto Joven , Zea mays , Zeaxantinas
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