ABSTRACT
Background Retinal angiomatous proliferation (RAP) is a subtype of neovascular age-related macular degeneration (AMD).There are currently very few studies on RAP.Objective This study was to explore the pathogenic mechanism of RAP in apolipoprotein E-deficient (ApoE-/-) mice with dyslipidemia.Methods Twenty-four 2-month-old SPF ApoE-/-mice were randomly divided into the high fat diet group and the normal diet group,and twelve 2-month-old C57BL/6 mice received the normal diet as controls.A diet with a higher content of fat was given for 4 consecutive months in the high fat diet group,and normal diet was given in the same way in the mice of the normal diet group.The mice were sacrificed at 6 months of age.The expression of vascular endothelial growth factor (VEGF) in the retinal pigment epithelial (RPE) cells,the expression of vascular endothelial growth factor receptor-2 (VEGFR-2) in the outer plexiform layer (OPL),microvascular density (MVD) and microvascular area (MVA) in the OPL were examined by immunohistochemistry and semi-quantitatively by histopathology with the Mias 2000 Imaging Analyzer System.The expression of VEGF protein in the retina was examined by Western blot.Results The MVD in the retinal OPL were (20.67±3.20) and (19.50± 1.87),respectively,in the ApoE-/-mice of the high fat diet group and the normal diet group,which were significantly higher than that (12.50±1.87) of the C57BL/6 normal diet group (all at P＜0.01).MVA in the retinal OPL were (626.49± 120.99) μm2 and (514.06±88.83) μm2 in the ApoE-/-mice of the high fat diet group and the normal diet group,respectively,showing a significant increase in comparison with the (336.52±84.96) μm2 of the C57BL/6 normal diet group (P＜0.01).The staining area of VEGF in RPE cells was (21 048±1849) μm2 in the ApoE-/-mice of the high fat diet group,showing a significant increase in comparison with the (17 116±2023) μm2 of the C57BL/6 normal diet group.However,no significant difference was found in the staining area of VEGF between the ApoE-/-mice with normal diet group and the C57BL/6 normal diet group ([17 854±2967] μm2 vs.[17 116±2023] μm2) (P＞0.05).Significant elevation was also seen in the staining area of VEGFR-2 in the retinal OPL of the ApoE-/-mice of the high fat diet group (12 193±3806)μm2 and the ApoE-/-mice of the normal diet group (11 969± 3616)xm2 compared with C57BL/6 mice of the normal diet group (5387±2225)μm2(all at P＜0.01).The relative expression values (VEGF/β-actin) of VEGF in the retinas were (1.51 ±0.32) and (1.17±0.39) in the ApoE-/-mice of the high fat diet group and the normal diet group,respectively,showing a significant increase in comparison with (0.28±0.14) of the C57BL/6 normal diet group (P＜0.01).Conclusions The expression of VEGF and VEGFR-2 in the retinas increases in the ApoE-/-mouse,which leads to the enlargement of MVD and MVA in the retinal OPL and subsequent RAP occurrence.
ABSTRACT
Background Dyslipidemia is one of the major causes of age-related macular degeneration (AMD).At present,the study of the preventive and treating methods of A MD is still a hot spot.Objective The purpose of this study was to observe the effect of tonifying the spleen and promoting blood circulation on the retina and Bruch membrane in apolipoprotein E-deficient (ApoE-/-) mice with dyslipidemia.Methods Thirty-six ApoE-/-mice aged 2 months were randomly divided into the normal diet group,high fat diet group and medicine group.A diet with a higher content of fat was given for 5 consecutive months to the mice of the high fat diet group and medicine group,and in the last month,a concoction that tonifies the spleen and promotes blood circulation was gavagely administered in the medicine group,and an equivalent volumes of normal saline solution was administered in the same way in the normal diet group and high fat diet group.Total plasma cholesterol (TC),low density lipoprotein (LDL)and triglyceride (TG) were detected by (ELISA? Name of assay?) using the 7170 Hitachi automatic biochemical analyzer,and morphological changes of the retina and Bruch membrane were examined by light microscopy and transmission electron microscopy.The number of outer nuclear layer (ONL) cells,retinal pigment epithelial (RPE) cells and the thickness of the Bruch membrane were examined by semi-quantitative histopathology with the Mias 2000 Imaging Analyzer System.Results The concentrations of TC,LDL and TG were (6.47 ±0.49) mmol/L,(1.46 ±0.10)mmol/L and (0.62 ±0.21) mmol/L,respectively,in 7-month-old mice of the medicine group,showing a significant reduction in comparison with (10.53 ±0.30) mmol/L,(1.90±0.13) mmol/L,(1.15±0.29) mmol/L of the high fat diet group,and (9.63 ± 0.18) mmol/L,(1.12 ± 0.15) mmol/L,(0.88 ± 0.21) mmol/L in the normal diet group (P＜0.05-0.01).The disorder and atrophy of ONL and RPE cells,divergence of fiber of the Bruch membranes were found in both the high fat diet group and normal diet control group under the light microscope,and drusen formed in some of the mice in the high fat diet group.However,ONL and RPE were well organized in the medicine group.The cell numbers in the ONL and RPE layer in the 7-month-old mice were (23 124.00±755.18) and (10.75±0.59),respectively,in the medicine group,(19 107.00 ± 1436.82) and (8.55 ± 1.11),respectively,in the high fat diet group,(21 663.00± 1073.27) and (9.75 ±0.58),respectively,in the normal diet group,with significant differences among them (P＜0.05-0.001).Thickness of the Bruch membrane in the medicine group extensively reduced in high fat diet group and normal diet control group (P＜0.01).The ultrastructures of the RPE and Bruch membrane were much more improved in the mdedicine group.Conclusions Tonifying the spleen and promoting blood circulation can attenuate hyperlipemia in ApoE-/-mouse;furthermore,it lessens the pathological abnormalities in the ONL,RPE and Bruch membrane.
ABSTRACT
AIM: To explore the fundus fluorescein angiographic characteristics and relevant clinical significance of age-related macular degeneration(AMD).METHODS: Fundus fluorescein angiography (FFA) was performed on 149 eyes of 112 patients using Nikon NF-505 fundus camera.RESULTS: Out of 149 eyes, 90 eyes were atrophic AMD (60.4%), 59 eyes were exudative AMD (39.6%) which were further divided, according to the composition and location of lesion, into subfoveal choroidal neovasculari-zation (CNV)(7 eyes of classic type, 26 eyes of occult type, 9 eyes with disciform cicatrices, juxtafoveal CNV(2 eyes of classic type, 12 eyes of occult type), and extrafoveal CNV(3 eyes of occult type).CONCLUSION: FFA can show CNV of AMD patients and its quality and location, which is helpful to guide the treatment and evaluate the prognosis.