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1.
Medicine (Baltimore) ; 95(6): e2680, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26871796

RESUMEN

Vitamin A is an essential fat-soluble vitamin important for the function of various body systems. In the eye, vitamin A is essential for the synthesis of visual pigments in photoreceptors. Vitamin A deficiency is a rare condition in the developed countries and might follow bariatric or intestinal bypass surgery.We present the case of a 67-year-old male that complained of visual loss and nyctalopia. Patient had bariatric surgery 15 years before for weight loss. Low serum levels of vitamin A confirmed the diagnosis and patient started vitamin A supplementation. Visual fields, macular thickness, and ganglion cell layer thickness were recorded and monitored 1 month, 6 months, and 1 year after the beginning of therapy. Visual fields were significantly altered and central macular thickness and ganglion cell layer thickness were reduced, but the first 2 showed a significant recovery with vitamin supplementation therapy. By the 1st month of treatment patient referred a complete remission of visual symptoms. Further, we observed hyperreflective material accumulating beneath a partially disrupted ellipsoid band in the high definition optical coherence tomography that also improved progressively with vitamin repletion.Newer and more sophisticated imaging systems have increased our knowledge of the mechanisms responsible for retinal diseases. To our knowledge, this is the first description of the effect of vitamin A deficiency and vitamin supplementation on macular thickness. This case also highlights the importance of considering bariatric bypass surgery as a cause of vitamin A deficiency in developed countries.


Asunto(s)
Suplementos Dietéticos , Retina/patología , Tomografía de Coherencia Óptica , Deficiencia de Vitamina A/tratamiento farmacológico , Deficiencia de Vitamina A/patología , Vitamina A/uso terapéutico , Vitaminas/uso terapéutico , Anciano , Cirugía Bariátrica/efectos adversos , Humanos , Masculino , Factores de Tiempo , Deficiencia de Vitamina A/etiología
2.
Oxid Med Cell Longev ; 2013: 213505, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23738034

RESUMEN

Oxidative stress is involved in the pathogenesis of several diseases such as atherosclerosis and age-related macular degeneration (AMD). ApoE-deficient mice (apoE(-/-)) are a well-established model of genetic hypercholesterolemia and develop retinal alterations similar to those found in humans with AMD. Thus supplementation with lutein or multivitamin plus lutein and glutathione complex (MV) could prevent the onset of these alterations. ApoE(-/-) mice (n = 40, 3 months old) were treated daily for 3 months with lutein (AE-LUT) or MV (two doses): AE-MV15 (15 mg/kg/day) and AE-MV50 (50 mg/kg/day) and were compared to controls with vehicle (AE-C). Wild-type mice (n = 10) were also used as control (WT-C). ApoE(-/-) mice showed higher retinal lipid peroxidation and increased VEGF expression and MMP-2 activity, associated with ultrastructural alterations such as basal laminar deposits, vacuoles, and an increase in Bruch's membrane thickness. While lutein alone partially prevented the alterations observed in apoE(-/-) mice, MV treatment substantially reduced VEGF levels and MMP-2 activity and ameliorated the retinal morphological alterations. These results suggest that oxidative stress in addition to an increased expression and activity of proangiogenic factors could participate in the onset or development of retinal alterations of apoE(-/-) mice. Moreover, these changes could be prevented by efficient antioxidant treatments.


Asunto(s)
Antioxidantes/farmacología , Apolipoproteínas E/deficiencia , Suplementos Dietéticos , Luteína/farmacología , Metaloproteinasa 2 de la Matriz/metabolismo , Retina/ultraestructura , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Apolipoproteínas E/metabolismo , Peso Corporal/efectos de los fármacos , Lámina Basal de la Coroides/efectos de los fármacos , Lámina Basal de la Coroides/enzimología , Lámina Basal de la Coroides/ultraestructura , Peroxidación de Lípido/efectos de los fármacos , Lípidos/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Óxido Nítrico/metabolismo , Retina/efectos de los fármacos , Retina/metabolismo
3.
Curr Eye Res ; 34(7): 543-52, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19899967

RESUMEN

PURPOSE: Apolipoprotein E(-/-) deficient (apoE(-/-)) mice develop hypercholesterolemia, atherosclerosis, and retinal alterations. We studied the oxidative status and vascular endothelial growth factor (VEGF) expression in murine retinal pigment epithelium-choroid (RPE) and Bruch's membrane (BM) ultrastructure and the effect of zeaxanthin. METHODS: Ten 6-month-old C57BL/6 and 40 apoE(-/-) mice were divided into four groups (n = 10 each) and fed different diets for 12 weeks based on body weight: wild type (WT) and apoE(-/-) (AE-Con) mice standard rodent chow; apoE(-/-) mice (AES) standard rodent chow with ascorbate (800 mg/kg), tocopherol (1053 mg/kg), and zinc (135 mg/kg); and apoE(-/-) mice the last diet plus zeaxanthin with either 0.4 g/kg (AES-Z04) or 4 g/kg feed (AES-Z4). RESULTS: Plasma total cholesterol (TC) and triglycerides (TG) and urine lipid peroxidation (isoprostanes) were measured. VEGF expression was determined in RPE-choroid homogenates. Zeaxanthin uptake was assessed in liver and retina by high-performance liquid chromatography; the retinal ultrastructure was analyzed by electron microscopy. AE-Con mice had higher plasma TC (p < 0.001) and TG (p < 0.001) values than WT mice. AE-Con mice had higher RPE-choroid-VEGF levels than WT mice (p < 0.05), BM thickness (p < 0.001) and presence of basal laminar deposits (BLamD). AES-Z4 resulted in lower urinary isoprostanes (p = 0.054) and lower VEGF expression in the RPE-choroid (p < 0.01). BM in the AES-Z4 animals had less confluent BLamD than AE-Con, AES, or AES-Z04 animals. CONCLUSIONS: We have reported that supplementation with zeaxanthin and antioxidants may delay or reverse alterations in the RPE and deposits in BM, and reduced VEGF expression observed in apoE(-/-) mice.


Asunto(s)
Antioxidantes/administración & dosificación , Apolipoproteínas E/deficiencia , Coroides/metabolismo , Hiperlipoproteinemia Tipo III/metabolismo , Retina/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Xantófilas/administración & dosificación , Animales , Ácido Ascórbico/administración & dosificación , Western Blotting , Lámina Basal de la Coroides/metabolismo , Lámina Basal de la Coroides/ultraestructura , Colesterol/sangre , Coroides/ultraestructura , Cromatografía Líquida de Alta Presión , Dieta , Suplementos Dietéticos , Dinoprost/análogos & derivados , Dinoprost/orina , Hiperlipoproteinemia Tipo III/patología , Peroxidación de Lípido , Hígado , Masculino , Ratones , Ratones Endogámicos C57BL , Retina/ultraestructura , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/ultraestructura , Tocoferoles/administración & dosificación , Triglicéridos/sangre , Zeaxantinas , Zinc/administración & dosificación
4.
Exp Eye Res ; 86(3): 470-9, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18243175

RESUMEN

The aim of the current study was to investigate the biochemical changes in the plasma and retina of apolipoprotein E deficient (apoE-/-) mice supplemented with various antioxidants. Ten wild type (WT-Con, C57BL/6) and 10 apoE-/- (AE-Con) mice received drinking water. Another 40 apoE-/- animals were divided into four groups of 10 mice each and received either chromocarbe diethylamine (AE-CD, 50mg/kg), cyaninosides chloride (AE-CC, 50mg/kg), multivitamin complex (AE-MC, 50mg/kg), or vitamins C and E (AE-CE, 100mg/kg and 200IU/kg). Cholesterol, triglycerides, and lipid peroxidation (thiobarbituric acid reactive substances [TBARS]) were measured in plasma, and TBARS and nitric oxide metabolites (NOx) concentration were determined in retinal homogenates. Transmission electron microscopy was performed to examine the retinal ultrastructure. AE-Con mice had significantly (P<0.05) increased oxidative stress in the plasma and retina with augmented production of retinal NOx compared with WT-Con mice. Retinal TBARS decreased in the AE-MC and AE-CE animals compared with the AE-Con group (P<0.05 and P<0.01, respectively). Only AE-CE treatment significantly (P<0.01) lowered retinal NOx. Morphologic retinal changes in the AE-Con group decreased in the AE-CE and AE-MC groups. There were no significant changes in the biochemical and structural parameters in the AE-CD and AE-CC groups. AE-Con mice had increased systemic and retinal oxidative stress compared with WT-Con animals. Vitamins C and E and the multivitamin-mineral complex reduced oxidative stress and ultrastructural retinal changes in this murine model of hypercholesterolemia.


Asunto(s)
Antioxidantes/farmacología , Apolipoproteínas E/deficiencia , Estrés Oxidativo/efectos de los fármacos , Retina/efectos de los fármacos , Vitaminas/farmacología , Animales , Ácido Ascórbico/farmacología , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Flavonoides/farmacología , Hiperlipoproteinemia Tipo III/metabolismo , Hiperlipoproteinemia Tipo III/patología , Peroxidación de Lípido/efectos de los fármacos , Lípidos/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica , Óxido Nítrico/metabolismo , Epitelio Pigmentado Ocular/efectos de los fármacos , Epitelio Pigmentado Ocular/ultraestructura , Retina/metabolismo , Retina/ultraestructura , Vitamina E/farmacología
5.
J Nutr Biochem ; 19(1): 40-8, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17531457

RESUMEN

Carotenoids are believed to inhibit oxidative stress. We investigated the protective effect of lutein and egg yolk supplementation on systemic and retinal alterations in apolipoprotein E-deficient (apoE-/-) mice, an experimental model of hypercholesterolemia and cardiovascular disease. Three-month-old wild-type and apoE-/- mice received one of the following: vehicle, lutein (0.09 mg/kg per day) or egg yolk (0.8 g/kg per day), by gastroesophageal cannula for 3 months. Total cholesterol (TC), triacylglycerol (TG) and lipid peroxidation (TBARS) were measured in plasma. TBARS levels were also determined in retinal homogenates. Ultrastructural morphology was analyzed by electron microscopy. ApoE-/- mice, with increased TC and TG concentrations, had higher systemic (P<.05) and retinal (P<.01) levels of lipid peroxidation than wild-type strains. Electron microscopy showed ultrastructural alterations (basal laminar deposits, open intercellular junctions, increased cytoplasmic vacuoles) in the retinas from apoE-/- mice. Egg yolk significantly reduced plasma TG (P<.05) and, without changes in TC, decreased plasma lipid peroxidation (P<.05). Lutein supplementation marginally affected the parameters. Less severe retinal ultrastructural alterations were observed in apoE-/- mice receiving either egg yolk or lutein. In the apoE-/- mouse model, egg yolk improved the lipid profile and reduced systemic lipid peroxidation (P<.05). While lutein and egg yolk did not seem to reduce retinal lipid peroxidation, a reduction in retinal ultrastructural alterations was observed.


Asunto(s)
Yema de Huevo , Hipercolesterolemia/terapia , Peroxidación de Lípido , Lípidos/sangre , Retina/ultraestructura , Animales , Apolipoproteínas E/deficiencia , Modelos Animales de Enfermedad , Yema de Huevo/química , Hipercolesterolemia/patología , Hipercolesterolemia/fisiopatología , Luteína/administración & dosificación , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica de Transmisión , Retina/química , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Uniones Estrechas/ultraestructura , Vacuolas/ultraestructura
6.
BMC Ophthalmol ; 6: 32, 2006 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-17034630

RESUMEN

BACKGROUND: Nonarteritic ischemic optic neuropathy affects the anterior portion of the optic nerve and is characterized by sudden, painless visual loss. The affected eye has a relative afferent pupillary defect. The typical funduscopic appearance includes optic disc edema, with associated nerve fiber layer hemorrhage. Risk factors include advanced age, systemic hypertension, nocturnal hypotension, diabetes mellitus, and a small cup-to-disc ratio. Bilateral presentation is rare. Postoperative optic neuropathy has been associated with nonocular surgery; risk factors include a combination of prolonged surgical times, acute systemic hypotension, anemia due to blood loss, or prone positioning. We report for the first time a patient with bilateral, simultaneous anterior ischemic optic neuropathy after elective transurethral prostatic resection. CASE PRESENTATION: A 66-year old man underwent surgery for benign prostatic hyperplasia. The preoperative blood pressure was 140/85 mmHg, hemoglobin 15.9 g/dL, and hematocrit 48.6%. Two hours postoperatively, the blood pressure, hemoglobin, and hematocrit dropped dramatically. One day later, transient horizontal diplopia developed. Funduscopy showed a congenitally small cup-to-disc ratio without papillary edema. Other ocular findings were unremarkable. By 4 days postoperatively, sudden and painless amaurosis bilaterally developed when the patient awoke with nausea and vomiting. Visual acuity was no light perception bilaterally. The optic discs were swollen with small hemorrhages. Scans of the head and orbits and electrolyte levels were normal. There were no responses on visual evoked potentials bilaterally. The blood pressure was 90/50 mm Hg, the hemoglobin 7.0 g/dL, and the hematocrit 22.9%, necessitating infusion of three units of packed red blood cells. The blood pressure, hematocrit, and hemoglobin increased to normal levels. Three months later the visual acuity remained no light perception. The pupils were unreactive and there was marked optic disc atrophy bilaterally. CONCLUSION: Bilateral and simultaneous acute ischemic optic neuropathy may be a rare but devastating surgical complication. The combination of anemia and hypotension may increase the risk of anterior ischemic optic neuropathy postoperatively after transurethral prostatic resection.


Asunto(s)
Neuropatía Óptica Isquémica/etiología , Hiperplasia Prostática/cirugía , Resección Transuretral de la Próstata/efectos adversos , Anciano , Anemia/etiología , Ceguera/etiología , Diplopía/etiología , Hematócrito , Humanos , Hipotensión/etiología , Masculino , Neuropatía Óptica Isquémica/sangre , Periodo Posoperatorio
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