Hoffmann S, Friedrichs U, Eichler W, Rosenthal A, Wiedemann P
Department of Ophthalmology, University of Leipzig, Liebigstrasse 10-14, 03411 Leipzig, Germany.
Graefes Arch Clin Exp Ophthalmol. 2002 Dec;240(12):996-1002. doi: 10.1007/s00417-002-0568-6. Epub 2002 Nov 19.
Advanced glycation end products (AGEs) are considered to be important modulators of angiogenesis and accumulate in choroidal neovascularization (CNV). Their effects regarding cells involved in proliferation of CNV [retinal pigment epithelial (RPE) cells, Müller cells and choroidal endothelial cells (CECs)] were investigated. Furthermore, the effects of AGEs on expression of matrix metalloproteinase-2 (MMP-2) and vascular endothelial growth factor (VEGF) by CECs were explored.
RPE cells, CECs and Müller cells were exposed to AGEs (10 microg/ml, 50 microg/ml and 100 microg/ml) for a time course of three days in their desired medium and proliferation was estimated by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. MMP-2 expression of AGE-stimulated CECs was determined by zymography and reverse-transcription polymerase chain reaction (RT-PCR) after 36 h of exposure. Furthermore, VEGF expression of AGE-stimulated CECs (50 microg/ml and 100 microg/ml) was determined by RT-PCR after an exposure time of 36 h.
AGEs in a concentration of 50 microg/ml and 100 microg/ml increased the proliferation of CECs (41% vs 46.1%; P<0.005). No AGE effect on RPE cell and Müller cell proliferation was seen. AGEs in all concentrations used upregulated the VEGF mRNA expression of CECs. Zymography and RT-PCR demonstrated the upregulation of MMP-2 by CECs after AGE exposure.
AGEs stimulate CEC proliferation, MMP-2 secretion and VEGF upregulation and may be important promoters of CNV formation in exudative AMD in vivo.
晚期糖基化终末产物（AGEs）被认为是血管生成的重要调节因子，并在脉络膜新生血管（CNV）中积聚。研究了其对参与CNV增殖的细胞[视网膜色素上皮（RPE）细胞、穆勒细胞和脉络膜内皮细胞（CECs）]的影响。此外，还探讨了AGEs对CECs中基质金属蛋白酶-2（MMP-2）和血管内皮生长因子（VEGF）表达的影响。
将RPE细胞、CECs和穆勒细胞在其所需培养基中暴露于AGEs（10微克/毫升、50微克/毫升和100微克/毫升）三天，通过3-（4,5-二甲基噻唑-2-基）-2,5-二苯基溴化四氮唑（MTT）法评估增殖情况。在暴露36小时后，通过酶谱分析和逆转录聚合酶链反应（RT-PCR）测定AGE刺激的CECs中MMP-2的表达。此外，在暴露36小时后，通过RT-PCR测定AGE刺激的CECs（50微克/毫升和100微克/毫升）中VEGF的表达。
浓度为50微克/毫升和100微克/毫升的AGEs增加了CECs的增殖（41%对46.1%；P<0.005）。未观察到AGEs对RPE细胞和穆勒细胞增殖的影响。所有使用浓度的AGEs均上调了CECs的VEGF mRNA表达。酶谱分析和RT-PCR显示AGE暴露后CECs中MMP-2上调。
AGEs刺激CECs增殖、MMP-2分泌和VEGF上调，可能是体内渗出性年龄相关性黄斑变性中CNV形成的重要促进因子。
