摘要
目的:观察食物中蛋白质的氨基与糖的醛基之间非酶性糖化反应的终产物晚期糖基化终产物对健康SD大鼠肾脏的影响。方法:实验于2005-03/07在南方医科大学肾内科实验室和南方医科大学附属南方医院动物实验中心完成。①分组及干预:选用健康雄性SD大白鼠40只,使用数字表法随机将大鼠分为两组:高晚期糖基化终产物饲料组,喂饲高晚期糖基化终产物饲料;低晚期糖基化终产物饲料组,喂饲低晚期糖基化终产物饲料。②高、低晚期糖基化终产物大鼠饲料的制作:普通大鼠饲料由广东省实验动物中心提供。高晚期糖基化终产物大鼠饲料加工方法:新鲜烤制的面包,取面包皮在烤箱烤180℃,2h,90℃,22h后,与普通大鼠饲料1∶1混合压制成颗粒饲料;低晚期糖基化终产物大鼠饲料:新鲜烤制的面包,取面包芯室温自然风干后与普通大鼠饲料1∶1混合后压制成颗粒饲料。③标本收集:分两批分别于干预后第2,3个月处死,收集24h尿液、腹主动脉抽血、留取部分肾组织。④检测指标:考马斯亮蓝法检测24h尿蛋白含量;自动生化分析仪测定肾功能、血脂、血糖及白蛋白水平;肾组织经固定、脱水、石蜡包埋、切片后行苏木精-伊红和PAS染色,观察组织病理改变。结果:大鼠40只均进入结果分析。①高晚期糖基化终产物饲料组大鼠血清及肾组织匀浆羧甲基赖氨酸含量自高于后第2个月即开始增加,至第3个月显著高于低晚期糖基化终产物饲料组大鼠(血清:16.1,7.8μg/L;肾组织匀浆:31.3,14.2μg/g;P<0.01)②至干预后第3个月,高晚期糖基化终产物饲料组大鼠24h尿蛋白含量显著高于低晚期糖基化终产物饲料组(54.54,11.51mg/24h,P<0.01)。③干预后第3个月肾组织病理学观察显示,高晚期糖基化终产物饲料组大鼠肾小球体积增大,系膜基质增生,表现为肾小球PAS阳性染色面积占整个肾小球面积之比值增大,显著高于低晚期糖基化终产物饲料组(肾小球体积:1.59×106,1.02×106mm3,P<0.05;系膜基质:0.87,0.53,P<0.05)。结论:高晚期糖基化终产物食物加重健康SD大鼠血循环和肾组织晚期糖基化终产物的潴留程度,增加肾组织损害,在肾小球肥大和硬化中起着关键性作用。长期食用富含晚期糖基化终产物的食物可能会对肾脏造成一定的损害。
AIM： To observe the effect of oral advanced glycation end products （AGEs）, the products of non-glycosylation reaction between amino in protein and aldehyde in sugar, in the form of bread crusts on kidney of healthy rats. METHODS： The experiment was carried out in the laboratory of Department of Renal Medicine, Southern Medical University and the animal laboratory center of Nanfang Hospital, Southern Medical University from June to December 2005. ①Grouping and intervention： 40 healthy male SD rats were selected and randomly divided into AGEs-rich diet group, which was fed with diet containing rich AGEs; and AGEs-poor diet group, which was fed with diet containing little AGEs. ② Preparation of diet： The common diet was provided by the Experimental Animal Center of Guangdong Province. The method to make the AGEs-rich diet： the crusts of the fresh bread after baked at 180℃for 2 hours, and 90 ℃ for 22 hours were mixed with the common diet at the ratio of 1：1 to press into granules diet; the AGEs-poor diet： The core of the fresh bread was air dried and mixed with the common diet at the ratio of 1：1 to press into granules diet. ③Collection of samples： The rats were killed at the 2^nd and 3^rd month of intervention, respectively to collect the urine in 24 hours and blood of abdominalis aorta and reserved part of kidney. ④Detection of indexes： The 24-hour urine protein was detected with Coomassie brilliant blue method; the renal function, blood lipids, blood glucose and albumin level were measured with automatic biochemistry analysor; the kidney tissue was fixed, dehydrated and embedded with wax to prepare the sections, which were given HE and PAS staining for observation of histopathological changes. RESULTS： All the 40 rats were involved in the result analysis.①The serum and carboxymethyllysine （CML） content in the tissue homogenate of the AGEs-rich group were increased at the 2^nd month and obviously higher than the AGEs-poor group at the 3^rd month （serum： 16.1, 7.8 μg,/L; homogenate： 31.3, 14.2μg,/g; P 〈 0.01）. ②At the 3^rd month, the content of 24-hour urine protein in the AGEs-rich group was significantly higher than the AGEs-poor group （54.54, 11.51 mg every 24 hours, P 〈 0.01）.③The histopathological observation showed that the glomerular volume and mesangial matrix were raised in the AGEs-rich diet group, appearing as the increase of proportion of PAS positive staining volume in the whole glomerulus, which was obviously higher than the AGEs-poor group （glomerular volume： 1.59×10^6, 1.02×10^6 mm^3, P 〈 0.05; mesangial matrix： 0.87, 0.53, P 〈 0.05）. CONCLUSION： AGEs-rich diet can worsen the retention of blood circulation and AGEs, and increase the damage to kidney tissues of healthy SD rats, which plays an important role in glomerular hypertrophy and sclerosis. Therefore, long-term consumption of diet rich in AGEs may result in damage of the kidney.
出处
《中国临床康复》
CSCD
北大核心
2006年第36期116-119,共4页
Chinese Journal of Clinical Rehabilitation
