丝胶对糖尿病大鼠视网膜黏附分子和缝隙连接蛋白-43表达的影响

发布时间：2018-04-22 04:23

本文选题：丝胶/药物 + 糖尿病视网膜病变/生理病理　；参考：《承德医学院》2017年硕士论文

【摘要】：糖尿病视网膜病变(diabetic retinopathy,DR)是近年来我国最重要的致盲性眼病之一,随着生活条件的改善和生活方式的改变,DR的发病率呈逐年上升趋势。DR的组织病理机制复杂,近年的研究认为DR是一种轻度的慢性炎症性疾病,病变早期即出现周细胞减少和视网膜基底膜增厚等微血管病变,如何早期改善视网膜微血管病变是治疗DR的关键。丝胶是蚕茧中的一种天然蛋白质,由18种氨基酸构成。在缫丝和精炼时,约占蚕丝总量25%的丝胶成分被丢弃,造成极大的资源浪费。研究发现,丝胶能降低多种炎症因子的活化能力,具有抗炎作用,且不良反应较少。但丝胶能否在DR的疾病过程中发挥重要的防治作用鲜有研究。本研究采用高脂高糖饮食联合链脲佐菌素诱导的方法建立2型糖尿病大鼠模型,观察丝胶对糖尿病模型大鼠视网膜中主要的黏附分子细胞间黏附分子-1(intercellular adhension molecule-1,ICAM-1)、血管细胞黏附分子-1(vascular cell adhesion molecule-1,VCAM-1)及缝隙连接蛋白43(connexin43,Cx43)相对表达水平的影响,探究丝胶对糖尿病大鼠视网膜微血管损伤的保护作用,为早期防治DR寻找一条新途径。目的:观察丝胶对糖尿病大鼠的视网膜中ICAM-1、VCAM-1和Cx43相对表达的影响,探讨丝胶对糖尿病大鼠视网膜微血管损伤的保护作用。方法:1将48只SPF级健康雄性SD大鼠,依照计算机数字随机分配法,随机分为:正常对照组、糖尿病模型组、丝胶治疗组和羟苯磺酸钙阳性药物对照组,每组大鼠数量为12只。糖尿病模型组、丝胶治疗组和羟苯磺酸钙阳性药物对照组大鼠均用高糖高脂饮食联合链脲佐菌素连续腹腔注射3d的方法制备2型糖尿病大鼠模型,成模后糖尿病模型组、丝胶治疗组和羟苯磺酸钙阳性药物对照组大鼠分别用生理盐水、2.4 g/(kg.d)丝胶溶液和0.2 g/(kg.d)羟苯磺酸钙溶液灌胃35d。2采用快速血糖仪法检测各组大鼠的空腹血糖。3苏木精-伊红染色观察各组大鼠视网膜组织的形态学变化。4westernblot技术检测各组大鼠视网膜组织中icam-1、vcam-1和cx43蛋白的相对表达量。5逆转录pcr技术检测各组大鼠视网膜组织中icam-1、vcam-1和cx43mrna的相对表达量。结果:1各组大鼠的fbg造模前各组大鼠fbg水平无明显差异,成模时,糖尿病模型组、丝胶治疗组和羟苯磺酸钙阳性药物对照组大鼠的fbg水平显著升高(p0.05)。药物干预治疗后,丝胶治疗组和羟苯磺酸钙阳性药物对照组与糖尿病模型组相比较,大鼠的fbg水平均显著降低(p0.05)。2各组大鼠视网膜的组织形态学表现正常对照组的大鼠视网膜的组织形态学表现正常,糖尿病模型组大鼠视网膜可见内界膜肿胀或断裂,偶见突出于内界膜的毛细血管内皮细胞,rgcs数量减少,丝胶治疗组和羟苯磺酸钙阳性药物对照组大鼠视网膜内界膜轻度增厚,内外核层细胞排列稍欠规则。3各组大鼠视网膜组织中icam-1、vcam-1和cx43蛋白的相对表达量糖尿病模型组大鼠视网膜组织中icam-1和vcam-1蛋白相对表达量较正常对照组大鼠均显著升高,而cx43蛋白的相对表达量显著下降(均p0.05)。丝胶治疗组和羟苯磺酸钙阳性药物对照组与糖尿病模型组比较,大鼠视网膜组织中icam-1和vcam-1蛋白的相对表达量均显著降低,而cx43蛋白的相对表达量显著升高(均p0.05)。4各组大鼠视网膜组织中icam-1、vcam-1和cx43mrna的相对表达量与正常对照组比较,糖尿病组大鼠视网膜组织中icam-1mrna和vcam-1mrna的相对表达量均显著升高,而cx43mrna的相对表达量显著下降(均p0.05);丝胶治疗组和羟苯磺酸钙阳性药物对照组与糖尿病模型组比较,大鼠视网膜组织中icam-1mrna和vcam-1mrna的相对表达量均显著下降,而cx43mrna的相对表达量显著升高(均P0.05)。结论:丝胶能够减轻糖尿病大鼠早期视网膜的微血管病变,从而对DR的发生和发展发挥防护作用,其机制可能是下调视网膜中ICAM-1和VCAM-1的表达以及上调Cx43的表达。
[Abstract]:Diabetic retinopathy (DR) is one of the most important blinding ophthalmopathy in China in recent years. With the improvement of living conditions and the change of life style, the incidence of DR is increasing year by year, and the histopathological mechanism of.DR is complicated. In recent years, the study found that DR is a mild chronic inflammatory disease, and the early pathological changes are Microvascular lesions such as pericytes decrease and retinal basement membrane thickening appear. How to improve retinal microvascular disease early is the key to the treatment of DR. Sericin is a natural protein in silkworm cocoon, consisting of 18 kinds of amino acids. In reeling and refining, the sericin components, which account for about 25% of the total silk, have been discarded, causing great waste of resources. It is found that sericin can reduce the activation of a variety of inflammatory factors, with anti inflammatory effects and less adverse reactions. But it is rarely studied whether sericin can play an important role in the disease process of DR. This study established a model of type 2 diabetic rats with high fat and high sugar diet combined with streptozotocin, and observed sericin on diabetes. The main adhesion molecule intercellular adhesion molecule -1 (intercellular adhension molecule-1, ICAM-1), -1 (vascular cell adhesion molecule-1, VCAM-1) and the relative expression level of connexin 43 in the rat retina of the disease model, to explore the retina microvasculature in diabetic rats The protective effect of injury in order to find a new way for early prevention and control of DR. Objective: To observe the effect of sericin on the relative expression of ICAM-1, VCAM-1 and Cx43 in the retina of diabetic rats, and to explore the protective effect of sericin on retinal microvascular injury in diabetic rats. Methods: 1, 48 SPF grade healthy male SD rats were randomly divided according to the computer digital score. The method was randomly divided into normal control group, diabetic model group, sericin treatment group and calcium hydroxybenzenate positive drug control group. The number of rats in each group was 12. The diabetic model group, the sericin group and the calcium hydroxybenzene sulfonate positive drug control group were prepared with high glucose and high fat diet combined with streptozotocin in continuous intraperitoneal injection of 3D 2. Diabetic rat model, diabetic model group, sericin group and calcium hydroxybenzene sulfonate positive drug control group, rats were treated with saline, 2.4 g/ (kg.d) Sericin Solution and 0.2 g/ (kg.d) hydroxybenzene sulfonate solution to 35d.2 by rapid glucose meter method to detect fasting blood glucose.3 hematoxylin eosin staining in each group. Morphological changes of retinal tissue in rats.4westernblot technique was used to detect the relative expression of ICAM-1, VCAM-1 and Cx43 protein in retina tissue of each group.5 reverse transcriptase PCR technique was used to detect the relative expression of ICAM-1, VCAM-1 and Cx43mRNA in retina tissues of each group. Results: the FBG level in each group of rats in each group of 1 groups was not clear before the model of the rats. The FBG level in the diabetic model group, the sericin therapy group and the calcium hydroxybenzoate positive drug control group increased significantly (P0.05). After the drug intervention, the sericin therapy group and the calcium hydroxybenzoate positive control group were compared with the diabetic model group, and the FBG level of the rats decreased significantly (P0.05) in each group of.2 rats. The histomorphology of the retina of the normal control group was normal. The retina of the diabetic model group could see the swelling or fracture of the inner boundary membrane in the retina of the rats. The number of RGCs in the capillary endothelial cells, which was prominent in the inner boundary membrane, decreased. The retina of the sericin therapy group and the calcium hydroxybenzoate positive drug control group had the inner boundary of the retina. The relative expression of ICAM-1, VCAM-1 and Cx43 protein in retina tissues of.3 rats was slightly thickened, and the relative expression of ICAM-1 and VCAM-1 protein in the retina tissue of the diabetic model group was significantly higher than that of the normal control group, while the relative expression of Cx43 protein decreased significantly (P0.05). Compared with the diabetic model group, the relative expression of ICAM-1 and VCAM-1 protein in the retina tissue of the sericin group and the calcium hydroxybenzene sulfonate positive control group decreased significantly, while the relative expression of Cx43 protein increased significantly (P0.05) in the retina of each group of.4, the relative expression of ICAM-1, VCAM-1 and Cx43mRNA in the retina tissues of each group was normal and normal. Compared with the control group, the relative expression of ICAM-1mRNA and vcam-1mrna in the retina tissues of the diabetic rats increased significantly, while the relative expression of Cx43mRNA decreased significantly (all P0.05). The comparison of the sericin therapy group and the calcium hydroxybenzoate positive control group with the diabetic model group was relative to the ICAM-1mRNA and vcam-1mrna in the retina tissue of the rats. The expression of Cx43mRNA was significantly decreased, while the relative expression of DR was significantly increased (P0.05). Conclusion: sericin can reduce the early retinal microvascular lesions in diabetic rats and protect the occurrence and development of DR. The mechanism may be to downregulate the expression of ICAM-1 and VCAM-1 in the retina and to increase the expression of Cx43.

【学位授予单位】：承德医学院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R587.2;R774.1

【参考文献】