糖基化终末产物对牛视网膜微血管内皮细胞和周细胞存活和形态的影响

目的 观察体外孵育的牛血清白蛋白(BSA)非酶促糖基化终末产物（AGEs）对牛视网膜微血管内皮细胞（BREC）和周细胞（BRP）存活和形态的影响。 方法 取终浓度为50mg/ml的牛血清白蛋白（BSA）、500 mmol/L D-葡萄糖，于37℃孵箱内避光孵育12周，制备外源性AGEs-BSA，经Sephacryl S-300层析纯化，十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS PAGE）蛋白电泳鉴定AGEs-BSA和coomassie 蛋白质定量法测定蛋白浓度。分设不同浓度梯度的AGEs-BSA实验组和BSA对照组，以及空白对照组，分别观察体外孵育的AGEs-BSA对体外培养的BREC和BRP的毒性作用。相差倒置显微镜观察500μg/ml AGEs-BSA和BSA作用48 h对BREC和BRP形态的影响。 结果 随着AGEs-BSA剂量的增加，细胞被抑制呈上升趋势。500μg/ml AGEs-BSA抑制BREC为空白对照组的（72.8±15.9）%，抑制周细胞为空白对照组的（64.8±9.0）%。低浓度AGEs-BSA对BREC有一定促增生作用，但与空白对照组比较无统计学意义（P=0.231）。相差倒置显微镜观察结果显示AGEs-BSA处理组细胞增殖受抑制，失去正常细胞形态，而BSA对照组细胞同空白对照组，细胞形态正常。 结论 AGEs-BSA在高浓度时，无论是对BREC还是BRP，都产生生长抑制作用，从而导致BRP的丢失，损伤血管功能。进一步证实了非酶糖化是糖尿病微血管并发症的一个重要原因。 (中华眼底病杂志, 2006, 22: 11-15)

Effects of advanced glycation end products on the survival and the morphology of bovine retinal endothelial cells and pericytes

Objective To study the effects of advanced glycation end (AGEs) products induced by bovine serum albumin (BSA) on the survival and the morphology of bovine retinal endothelial cells (BREC) and pericytes (BRP). Methods BSA with the final concentration of 50 mg/ml was incubated in PBS, containing 500 mmol/L D-glucose, for 12 weeks under 37℃. AGEs-BSA was purified by Sephacryl S-300 column chromatography and was confirmed by sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). The concentration of AGEs-BSA was determined by the method of commassie protein assay. In order to detect the toxic effects of AGEs-BSA on cultured BREC and BRP, groups of AGEs-BSA and BSA with different concentration and untreated control were set up. Phase contrast microscope was used to observe the effect of AGEs-BSA and BSA (with the concentration of 500μg/ml and actuation duration of 48 hours) on morphology of BREC and BRP. Results As the dosage of AGEs-BSA increased, the number of inhibited cells increased. When the concentration of AGEs-BSA was 500μg/ml, the inhibited BREC in AGEs-BSA group was (72.8±15.9)% of which in untreated control group, and the inhibited BRP was (64.8±9) % of which in untreated control group. AGEs-BSA with low concentration promoted the proliferation of endothelial cells, but there was no significant difference between AGEs-BSA and the control group (P=0.231). Inhibited proliferation and abnormal morphology were seen under the phase contrast microscope while the normal morphology of cells was found in BSA and control group. Conclusion AGEs-BSA with the high concentration may inhibit the growth of both BREC and BRP, which leads the loss of BRP and damage of vascular function. These results suggest that nonenzymatic glycosylation plays a major role in diabetic complications. (Chin J Ocul Fundus Dis, 2006, 22: 11-15)