儿茶素微胶囊对肾病综合征大鼠肾功能的影响

背景儿茶素是一种抗氧化能力很强的天然植物抗氧化剂,因其稳定性较差且生物利用率较低,需对剂型加以改进以提高其效能.目的研究儿茶素微胶囊对肾病综合征大鼠肾功能的影响.设计随机对照研究.单位湖南农业大学生化与发酵工程实验室和中南大学湘雅二医院小儿肾病研究室.材料实验在上述两单位的实验室完成.选取6周龄体质量相近(180～220g)的SD雌性大鼠120只,随机分成对照组、肾病组、激素治疗组、VitE治疗组、儿茶素治疗组、儿茶素微胶囊治疗组,每组20只.方法实验第1天对照组尾静脉1次注射0.1mL生理盐水,其他各组尾静脉1次注射阿霉素(5 mg/kg).激素治疗组自实验第2周末皮下注射地塞米松[1.8mg/(kg·d)]至第6周末实验结束.VitE治疗组自实验第2周末行最大剂量维生素E灌胃[50mg/(kg·d)]至第6周末实验结束.儿茶素治疗组自实验第2周末行儿茶素灌胃[50mg/(kg·d)]至第6周末实验结束.儿茶素微胶囊治疗组自实验第2周末行儿茶素微胶囊灌胃[50mg/(kg·d)]至第6周末实验结束.应用考马斯亮蓝法测定不同时期24h尿蛋白排泄量,采用半定量评分法分别对肾小球、肾小管间质的病理改变进行计分评价.主要观察指标大鼠24h尿蛋白排泄量和肾脏病理积分.结果实验末,24 h尿蛋白的排泄量依次为肾病组＞VitE治疗组＞儿茶素治疗组＞激素治疗组＞儿茶素微胶囊治疗组＞对照组;肾病理积分依次为肾病组＞VitE治疗组＞儿茶素治疗组＞儿茶素微胶囊治疗组＞激素治疗组＞对照组.24h尿蛋白排泄量与肾脏病理积分呈高度正相关(r=0.827,P＜0.01).结论儿茶素微胶囊可以通过降低大鼠24h蛋白尿的排泄量,减轻肾脏损害,延缓肾脏病理慢性进展,其对肾病综合征大鼠肾功能的改善比游离儿茶素好.

Effects of catechin microcapsules on renal function of rats with nephrotic syndrome

BACKGROUND: Catechin is a kind of natural plant antioxidant with strong antioxidative capability, but the stability and bioavailbility are low. So the dosage type should be improved to promote its effects.OBJECTIVE: To study the effects of catechin microcapsules on renal function of rats with nephrotic syndrome.DESIGN: A randomized and controlled trial.SETTING: Laboratory of biochemistry and fermentation engineering, Hunan Agricultural University and Laboratory of children nephritic syndrome, the Second Hospital of Xiangya, Central South University.MATERIALS: The experiment was performed in the laboratories mentioned above. A total of 120 female SD rats, about 6 weeks old with the mass of 180 - 220 g, were randomly divided into six groups: control group, nephrotic group, dexamethasone-treatment group, VitE-treatment group, catechin-treatment group and catechin microcapsules-treatment group with 20 in each group.METHODS: In the first day of experiment, saline(0. 1 mL) were intravenously administered to the rats in control group and adriamycin (5 mg/Kg)was intravenously administered to all rats except the control group. From the second weekend to the sixth weekend of experiment, rats in dexamethaby gastric perfusion. The quantity of 24-hour urinary proteins was detected with Coomassie brilliant blue method. A semiquantitative score was used to evaluate the degree of glomerular and tubulointerstitial lesions.MAIN OUTCOME MEASURES: The excretion quantity of 24-hour urinary proteins and the renal pathologic scores.RESULTS: At the end of the experiment, the order from high to low for excretion quantity of 24-hour urinary proteins was nephrotic group,VitE-treatment group, catechin-treatment group, dexamethasone-treatment group, catechin microcapsules-treatment group and control group; and that for renal pathologic scores was nephrotic group, VitE-treatment group, catechin-treatment group, catechin microcapsules-treatment group, dexamethasone-treatment group and control group. The excretion quantity of 24-hour urinary proteins was positively correlated with the renal pathologic scores (r=0.827, P ＜0.01).CONCLUSION: The catechin microcapsule might decrease the excretion quantity of 24-hour urinary proteins and relieve renal lesion of rats so as to slow chronic progression of renal lesion, and the effect was better than that of free catechin.