PPAR-γ激动剂对早期糖尿病大鼠MCP-1表达的影响

发布时间：2018-05-20 23:46

本文选题：过氧化物酶体增生物激活受体-γ + 糖尿病性视网膜病变　；参考：《泸州医学院》2010年硕士论文

【摘要】：目的：建立糖尿病大鼠动物模型,给予过氧化物酶体增生物激活受体-γ(peroxisome proliferator-activated receptor-gamma, PPAR-y)激动剂罗格列酮对大鼠进行干预,观察其血清和视网膜中单核细胞趋化蛋白-1(monocyte chemotactic protein-1, MCP-1)表达及视网膜微血管的变化,探讨外源性PPAR-γ激动剂对早期糖尿病性视网膜病变的保护作用及其机制。方法：腹腔注射链脲佐菌素(streptozotocin, STZ)制备糖尿病(diabetes mellitus, DM)动物模型。选用健康雄性Wistar大鼠90只,随机分为三组：正常对照组(C组,n=30),糖尿病模型空白对照组(D组,n=30),糖尿病模型罗格列酮干预组(R组,n=30)；糖尿病模型罗格列酮干预组每日给予罗格列酮3mg/kg灌胃,正常对照组和糖尿病模型空白对照组则给予同等剂量的生理盐水灌胃(相同容积)。所有大鼠每周测体重和空腹血糖两次。分别于给药后4w、8w和12w处死各组大鼠,采集大鼠血液及眼球标本；行视网膜消化铺片,观察视网膜微血管形态,并行内皮细胞(endothelial cell, E)和周细胞(perithelial cell, P)计数、计算E/P值；伊文思蓝法测定血-视网膜屏障的通透性；免疫组化法检测视网膜中MCP-1的阳性表达；酶联免疫吸附法(enzyme linked immunosorbent assay, ELISA)定量测定血清中MCP-1的含量。结果：1.各时间点D组和R组大鼠体重均明显低于C组；空腹血糖均明显高于C组(P＜0.01)。2.与相应的C组比较：D组4w开始出现体重减轻,血-视网膜屏障通透性增加,血清及视网膜中MCP-1的表达增多；8w开始出现视网膜毛细血管壁周细胞减少,内皮细胞增多,差异均具有统计学意义(P0.01)；且随着时间的延长,视网膜微血管病变程度逐渐加重,呈时间依赖性改变。3.应用罗格列酮干预后,视网膜微血管病理损害明显减轻。与相应的D组比较：R组4w开始出现体重增加,血.视网膜屏障通透性降低,血清及视网膜中MCP.1的表达减少,8w开始出现视网膜毛细血管壁周细胞增多,内皮细胞减少,差异均具有统计学意义(P＜0.01)；且随着干预时间的延长,视网膜微血管病变程度逐渐减轻,呈时间依赖性改变。结论：1.正常大鼠血清及视网膜中存在少量的MCP.1表达。2.罗格列酮可能通过激活PPAR-γ、下调炎性因子MCP.1的表达对早期糖尿病性视网膜病变起到一定的保护作用,可能成为其早期防治的新靶点。3.应用STZ腹腔注射可成功复制糖尿病动物模型,简便快捷；模型病变典型,成功率高,死亡率低。
[Abstract]:Aim: to establish an animal model of diabetic rats and to treat rats with rosiglitazone, a peroxisome proliferator-activated receptor-gamma (PPAR-Y) agonist. To observe the expression of monocyte chemoattractant protein-1 chemotactic protein-1 (MCP-1) and the changes of retinal microvessels in serum and retina, and to explore the protective effect of exogenous PPAR- 纬 agonist on early diabetic retinopathy and its mechanism. Methods: streptozotocin (STZZ) was injected intraperitoneally to establish diabetic Mellitus (DM) animal model. 90 healthy male Wistar rats were selected. The rats were randomly divided into three groups: normal control group (n = 30), control group C (n = 30), control group D (n = 30), rosiglitazone group (n = 30) and rosiglitazone group (n = 30), and rosiglitazone group (n = 30) were given rosiglitazone 3mg/kg daily. Normal control group and diabetes model blank control group were given the same dose of normal saline (same volume). All rats were measured twice a week for body weight and fasting blood glucose. Rats in each group were killed at 4 weeks and 12 weeks after administration, blood and eyeball samples were collected, retinal microvessel morphology was observed, endothelium cell endothelial cell (E) and pericyte periepithelial cell (P) count, and E / P value were calculated. The permeability of blood-retinal barrier was determined by Evans blue method, the positive expression of MCP-1 in retina was detected by immunohistochemical method, and the content of MCP-1 in serum was determined quantitatively by enzyme linked immunosorbent assay, ELISA) by enzyme linked immunosorbent assay (Elisa). The result is 1: 1. At each time point, the body weight of group D and group R were significantly lower than those of group C, and the fasting blood glucose was significantly higher than that of group C (P < 0.01). Compared with the corresponding group C, the weight loss and the permeability of blood-retinal barrier began to appear in group C at 4 weeks, and the expression of MCP-1 in serum and retina began to decrease and endothelial cells increased at 8 weeks. The difference was statistically significant (P 0.01), and with the extension of time, the degree of retinal microangiopathy gradually increased, showing a time dependent change of .3. After treated with rosiglitazone, the pathological damage of retinal microvessels was significantly alleviated. Compared with the corresponding group D, the weight gain and blood began to appear in the group of 4 weeks. The retinal barrier permeability was decreased, and the expression of MCP.1 in serum and retina began to increase at 8 weeks, and the endothelial cells decreased, the difference was statistically significant (P < 0.01), and with the prolongation of the intervention time, the retinal capillary pericytes increased and the endothelial cells decreased (P < 0.01). The degree of retinal microangiopathy gradually decreased, showing a time-dependent change. Conclusion 1. There is a small amount of MCP.1 expression. 2. 2 in normal rat serum and retina. Rosiglitazone may play a protective role in early diabetic retinopathy by activating PPAR- 纬 and down-regulating the expression of inflammatory factor MCP.1. Rosiglitazone may be a new target for early prevention and treatment of diabetic retinopathy. STZ intraperitoneal injection can be used to successfully reproduce diabetic animal model, which is simple and fast, typical pathological changes, high success rate and low mortality.
【学位授予单位】：泸州医学院
【学位级别】：硕士
【学位授予年份】：2010
【分类号】：R774.1

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