摘要
目的:探讨能够影响糖尿病大鼠视网膜组织中细胞凋亡的因素。方法:实验于2003-03/2004-03在中山大学医学动物实验中心完成。选取无菌级成年纯系雄性Wistar大鼠40只,禁食12h后随机分成糖尿病组和对照组,20只/组。糖尿病组腹腔一次性注射链脲佐菌素65mg/kg诱发糖尿病,对照组腹腔注射等量柠檬酸盐缓冲液。于糖尿病组发病后4,6,12,16周用酶联免疫分析法检测两组大鼠视网膜细胞凋亡程度,硫代巴比妥酸荧光法检测两组大鼠视网膜组织中脂质过氧化物含量,化学发光法检测两组大鼠视网膜组织中超氧化物歧化酶的活性,并与空腹血糖、糖化血红蛋白、血中自由基含量及糖尿病病程进行相关分析。组间比较行t检验,组内比较行H检验,各指标间的相关性采用双变量相关分析。结果:实验纳入大鼠40只,均进入结果分析。①两组大鼠发病前后不同时期空腹血糖的变化:两组大鼠在发病前基本相近[(4.16±1.1),(4.16±1.2)mmol/L,P>0.05],发病后4,6,12,16周糖尿病组均显著高于对照组(t>5.1679,P<0.001)。②两组大鼠发病后4,6,12,16周各项指标检测结果比较:与对照组比较,糖尿病组糖化血红蛋白、全血中自由基含量、视网膜组织中脂质过氧化物水平、视网膜细胞溶解液吸光值均明显增高(t=2.4388,P<0.05;t>2.5673,P<0.01;t>2.8514,P<0.01;t>2.9155,P<0.01),而视网膜组织中超氧化物歧化酶活性显著降低(t>2.9612,P<0.01)。③各指标间相关性分析:糖尿病组视网膜细胞凋亡量与空腹血糖浓度、糖化血红蛋白水平、血中自由基含量、视网膜组织中过氧化脂质水平和糖尿病病程呈高度正相关(r=0.7584,0.7844,0.7962,0.8248,0.6246,P均<0.001),而与视网膜组织中超氧化物岐化酶呈高度负相关(r=-0.8617,P<0.001)。结论:糖尿病大鼠发病后4周即发现血中自由基含量增加、视网膜组织中抗氧化机能下降、同时伴有视网膜细胞凋亡。糖尿病大鼠视网膜细胞凋亡的程度与空腹血糖浓度、糖化血红蛋白水平、血中自由基含量、视网膜内脂质过氧化物的增加和超氧化物歧化酶活性的降低密切相关。提示糖代谢异常和机体抗氧化机能的下降可能对糖尿病视网膜组织中细胞凋亡具有促进作用。采取有效措施提高抗氧化机能、降低视网膜组织中细胞凋亡的程度将可能对预防糖尿病视网膜的发生发展有所益。
AIM： To investigate the factors that influence the apoptosis in the retinal tissue of diabetic rats. METHODS： The experiment was carried out in the experimental center of medical animal of Sun Yat-sen University between March 2003 and March 2004. Forty adult pure male Wistar rats were randomly divided into two groups after fasted for 12 hours： diabetic group （n=20） and control group （n=20）. The rats in the diabetic group were induced to develop diabetes by once intraperitoneal injection of streptocotocin （65 mg/kg）, and those in the control group were treated with intraperitoneal injection of saline of citrate buffer of the same volume. At 4, 6, 12 and 16 weeks after diabetic attack, the severity of apoptosis in the retinal tissue was deteced with enzyme-linked immunoassay （EIA） in both groups, the content of lipid peroxidation in the retinal tissue was detected with the thiobarbituric acid fluorescent assay, the activities of superoxide dismutase ih the retinal tissues were detected by chemiluminescence. The relations of the apoptosis with levels of fasting blood glucose, glycosylated hemoglobin, the content of free radicals in blood and the disease course were also analyzed. The t test and H test were applied in the intergroup and intragroup comparisons respectively, the relation between the indexes was analyzed with bivariate correlation analysis. RESULTS： All the 40 rats were involved in the analysis of results. ① The changes of fasting blood glucose before and after the diabetic attack between the two groups： The levels of fasting blood glucose before attack were close [（4.16±1.1）, （4.16±1.2） mmol/L, P 〉 0.05], but all significantly higher in the diabetic group than in the control group at 4, 6, 12 and 16 weeks after attack （t 〉 5.167 9, P 〈 0.001）. ②Comparison of the indexes at 4, 6, 12 and 16 weeks after attack between the two groups： Compared with the control group, the content of glycosylated hemoglobin, content of free radicals in whole blood, level of lipid peroxidation in retinal tissue and the absorbance of retinal cell lysis buffer were all increased in the diabetic group （t=2.438 8, P 〈 0.05; t〉2.567 3, P 〈 0.01; t〉2.851 4, P 〈 0.01; t 〉 2.915 5, P 〈 0.01）, but the activity of SOD in the retinal tissue was significantly decreased （t 〉 2.961 2, P 〈 0.01）. ③ Correlation analysis among the indexes： In the diabetic group, the apoptotic amount in retinal tissue had highly positive correlation with the concentration of fasting blood glucose, level of glycosylated hemoglobin, content of free radicals in blood, level of lipid peroxidation in retinal tissue and diabetic course （r =0.758 4, 0.784 4, 0.796 2, 0.824 8, 0.624 6, P 〈 0.001）, but had highly negative correlation with the SOD activity in retinal tissue （r=-0.861 7, P 〈 0.001）. CONCLUSION： At 4 weeks after diabetic attack, the content of free radicals in blood is increased, the antioxidative function in the retinal tissue was decreased, and the apoptosis in retinal tissue is also accompanied. The severity of apoptosis in the retinal tissue of diabetic rats is closely associated with the concentration of fasting blood glucose, level of glycosylated hemoglobin, content of free radicals in blood, increased level of lipid peroxidation and decreased activity of SOD in retinal tissue. It is indicated that the disturbance of carbohydrate metabolism and decrease of the organic antioxidative function may accelerate the apoptosis in the diabetic retinal tissue, It is good for the prevention of the occurrence and development of diabetic retinopathy to adopt effective measures to enhance the antioxidative function and decrease the severity of apoptosis in the retinal tissue,
出处
《中国临床康复》
CSCD
北大核心
2005年第39期72-74,共3页
Chinese Journal of Clinical Rehabilitation
基金
广西自然科学基金资助(0007036)~~
作者简介
何剑峰,男,1960年生,湖南省资兴市人,汉族,2004年中山大学毕业,博士,副主任医师,主要从事眼眶病和糖尿病视网膜病变的研究. hejianf@163.com
