医药学论文：抗氧化剂儿茶素微胶囊制备及其对肾病大鼠的疗效

【摘要】 目的 研究儿茶素的抗氧化活性， 儿茶素微胶囊的制备工艺及其对大鼠肾病综合征的疗效. 方法 利用化学发光法测定天然植物抗氧化剂清除活性氧的能力;采用喷雾干燥法制备儿茶素微胶囊;通过急性毒性和亚慢性毒性试验评价微胶囊的安全性;建立阿霉素肾病综合征大鼠模型，利用考马斯亮蓝法测定尿蛋白的排泄量，半定量评分法分别评定肾小球、肾小管间质的病理改变。结果 儿茶素、迷迭香提取物和葡萄籽提取物清除的IC50分别为6.16、184.29和15.86μg/mL;清除·OH的IC50分别为0.59、39.89和2.93μg/ml; 清除H2O2的IC50分别为0.69、16.80和1.34μg/ml，说明儿茶素清除活性氧的能力比迷迭香提取物和葡萄籽提取物强; 喷雾干燥法制备性能优良的儿茶素微胶囊的主要工艺参数为:固形物含量25%，芯材与壁材的比例为6∶4，乙基纤维素与聚乙二醇的比例为8∶2;儿茶素微胶囊属实际无毒级、无毒副作用;大鼠肾病综合征动物模型实验末， 各组不同处理大鼠24h尿蛋白排泄量依次为:肾病组＞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＞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 利用喷雾干燥法制备的儿茶素微胶囊能降低肾病综合征大鼠24h尿蛋白的排泄量，减轻肾脏损害，延缓肾脏病理慢性进展，其对肾病综合征的疗效比游离儿茶素好。

【关键词】 儿茶素 抗氧化活性 肾病综合征 大鼠

Preparation and therapeutic effects of antioxidant catechin microcapsules on rats with nephrotic syndrome

【Abstract】 Objective To research the antioxidant capacity of catechin， prepare the microcapsules and study on the therapeutic effects of catechin microcapsules on rats with nephrotic syndrome.Methods Chemiluminescence was used to research the scavenging capacities on reactive oxygen of some natural plant antioxidants. Spray drying was applied to prepare microencapsulated catechin. The acute and subchronic toxicity tests were applied to evaluate the safety of microencapsulated catechin. The 24h urinary proteins were detected by Commassie brillant blue. A semiquantitative score was used to evaluate the degree of glomerular and tubulointerstitium lesions.Results The IC50 of scavenging　O2·- for catechin， the extraction from rosemary and grape seed were separately 6.16， 184.29 and 15.86 μg/mL: The IC50 of scavenging ·OH were separately 0.59， 39.89 and 2.93 μg/mL; The IC50 of scavenging H2O2 were separately 0.69， 16.80 and 1.34 μg/ml. It was the strongest that the capacities on scavenging three reactive oxygens of catechin. The optimum technological parameters which prepared microencapsulation of catechin in spray drying were as follows: The concentration of slurry was 25%; the ratio of sodium catechins and wall material was 6∶4; the ratio of ethyl cellulose and polyethylene glycol was 8∶2. The microencapsulated catechin had actually no toxicity. At the end of the experiment， the excretions of 24h urinary proteins were separately nephrotic group， catechin-treated group， dexamethasone-treated group， microencapsulation of catechin-treated group and control group; the renal pathologic scores were separately nephrotic group， catechin-treated group， microencapsulation of catechin-treated group， dexamethasone-treated group and control group. the excretions of 24h urinary proteins were positively correlated with the renal pathologic scores（r＝0.827，P＜0.01）.Conclusion The effects which microencapsulation of catechins in spray drying slowed chronic progressive kidney lesions through decreasing the excretions of 24h urinary protein were better than those of free catechins.