张 旭1 陈朝银2 董珺琳1 蔡金燕1 赵声兰1(1云南中医学院中药学院 2昆明理工大学生命科学与技术学院)
（本论文荣获“第三届兰茂论坛”优秀论文二等奖）
摘要：目的 研究没食子酸对谷氨酸钠诱导的肥胖小鼠脂代谢异常的改善作用。方法 新生乳鼠皮下注射3mg/g/d谷氨酸钠建立肥胖模型，模型建立后将小鼠分为正常对照组、模型组、阳性对照组（辛伐他汀30mg/kg/d）、没食子酸高剂量组（400mg/kg/d）和没食子酸低剂量组（200mg/kg/d）。连续给药10周，于末次给药后禁食不禁水12 h，摘眼球取血，摘取脏器及脂肪，测定脏器指数和脂肪指数。用试剂盒测定血清和肝脏中TC、TG、HDL-C、LDL-C含量，测定血清瘦素水平，肝脏SOD、GSH-Px和MDA等水平。结果 与正常对照组相比，模型组小鼠体重及脂肪明显增加（p<0.05），血清及肝脏中TC、TG、LDL-C含量明显升高，血清中瘦素水平明显降低（p<0.05），肝脏中SOD、GSH-Px水平明显降低，MDA水平明显升高（p<0.05）。与模型对照组相比，没食子酸组小鼠体重及脂肪明显减少（p<0.05），血清及肝脏中TC、TG含量明显降低（p<0.05），肝脏中SOD、GSH-Px水平明显升高，MDA水平明显降低（p<0.05）。结论：没食子酸对谷氨酸钠诱导的肥胖小鼠的脂代谢异常有明显的改善作用和减肥降脂作用。
关键词：没食子酸；肥胖小鼠；脂代谢
Abstract：objective, Study on improving effect of gallic acid on glutamate induce abnormal of lipid metabolism in obesity mice. Method, The obesity model was established through subcutaneous injection of 3mg/g/d sodium glutamate on neonatal mice. After the model was established, the mice were divided into normal control group, model group, positive control group (simvastatin 30mg/kg/d), high dose group of gallic acid(400mg/kg/d) and low dose group of gallic acid (200mg/kg/d). Continuous filling of stomach for 10 weeks, after the drug was given at the last time, fasting can not help but water 12 h. Take blood from the eye, pick the liver, heart, spleen, kidney organs and adipose, organ index and fat index were measured. The contents of HDL-C, TG, LDL-C and TC in serum and liver were determined by using the corresponding reagent kit, and the serum leptin level was determined by ELISA kit. Simultaneous determination of SOD, GSH-Px and MDA levels in liver. Result, Compared with the normal control group, the body weight and fat were significantly increase in the model group (p<0.05), the contents of TC, TG and LDL-C in serum and liver were significantly increase, the serum leptin level was significantly reduce(p<0.05), the level of SOD and GSH-Px in the liver was significantly reduce, and the level of MDA was significantly increase (p<0.05). Compared with the model control group, the body weight and fat were significantly reduce in the gallic acid group mice (p < 0.05). in the serum and liver, the level of TC and TG were significantly reduce (p< 0.05); in the liver, SOD and GSH-Px levels were significantly increase, MDA level was significantly decrease (P < 0.05). Conclusion: Gallic acid Have a significant improving the abnormal lipid metabolism and lipid-lowering effect on glutamate induce obese mice.
Keywords：gallic acid; obese mice; lipid metabolism
Study on Improving the Effect of Gallic Acid on Glutamate Induce Abnormal of Lipid Metabolism in Obese MiceZHANG Xu1, CHEN Chao-yin2, ZHAO Sheng-lan1*，DONG Jun-lin1，CAI jin-yan1(1.Faculty of Traditional Chinese Medicine, Yunnan University of Traditional Chinese Medicine, Kunming ,650500, China; 2.Faculty of life science and technology, Kunming University of Science and Technology, Kunming 650500, China)没食子酸（GA）又名棓酸、五倍子酸，是多种中药及其复方制剂中重要的功效成分。广泛存在于五倍子、葡萄、茶叶、石榴等[1-4]植物中, 是自然界存在的一种多酚类化合物。具有明显抗肿瘤[5]、抗炎、抗病毒[2]、抗氧化[6]、抑菌[7]和心脑血管保护[8]等药理作用，其酯类化合物作为抗氧化剂被广泛应用于食品、制药及轻工等行业。没食子酸能显著降低链脲霉素所致糖尿病大鼠的血糖水平，降糖机制可能与促进胰岛素分泌、提高血清Ｃ肽水平以及加强胰岛β细胞再生等效应有关[4]。
谷氨酸钠(monosodium glutamate, MSG) 常用来复制肥胖模型[9]，新生乳鼠连续皮下注射实验剂量的MSG可以广泛破坏大脑弓状核和部分脑室周围结构，引起肥胖，并伴有糖代谢紊乱、胰岛素抵抗、高血脂和高血压等代谢综合征[10~11]。本文采用新生乳鼠皮下注射谷氨酸钠复制肥胖小鼠模型，研究没食子酸对肥胖小鼠脂代谢异常的改善作用和减肥降脂作用。
1、材料与方法
1.1 材料与仪器
材料：昆明种小鼠30对(雌雄配对)，体重22g左右（动物许可证号：SCXK(川)2013-24）；谷氨酸钠；没食子酸≥98%（源叶生物科技有限公司）；辛伐他汀（杭州默沙东制药有限公司）；甘油三酯测定试剂盒、总胆固醇测定试剂盒等（南京建成生物科技股份有限公司）；生理盐水；70%乙醇等。
仪器：INFINITE M200 PRO酶标仪（瑞士TECAN公司）；UV759S型紫外-分光光度计（上海精科）；先行者TM（OHAUS）分析天平(奥豪斯（上海）有限公司)；湘仪H1850R台式高速冷冻离心机（湖南湘仪实验室仪器开发有限公司）；电热恒温水浴锅（上海医疗器械五厂）等。
1.2方法
1.2.1 MSG诱导的肥胖小鼠模型建立
肥胖小鼠模型的建立： 12 周龄没有生育过的雌雄健康昆明种小鼠配对繁殖，确定雌鼠怀孕后，将其分出单独喂养，每只母鼠喂养新生乳鼠数量控制在8-10只。新生乳鼠分为MSG 干预组和生理盐水对照组。MSG干预组：乳鼠出生后第 2-8 天，皮下注射谷氨酸钠3mg/g/d（生理盐水溶解），生理盐水对照组：给以等体积生理盐水。正常哺乳喂养3周后，小鼠断乳喂以普通饲料饲养，4周后小鼠雌雄分笼喂养。
1.2.2 分组及给药
乳鼠喂养到6周龄后，将上述MSG干预组分为4组，分别为模型组（灌生理盐水）、阳性对照组（辛伐他汀30mg/kg/d）、没食子酸低剂量组（200mg/kg/d）、没食子酸高剂量组（400 mg/kg/d），每组10只。试验期间，各组小鼠自由进食和饮水，饲养环境温度25±2℃，湿度55±5%，昼夜交替周期12 h，每天灌胃给药一次，连续给药10周。
1.2.3 实验指标的测定
实验小鼠于末次给药后禁食不禁水16 h，称体重，测量体长（鼻尖至肛门的长度），摘眼球取血，分离血清。解剖小鼠，摘取小鼠体的肝脏、心脏、脾脏、肾脏及睾丸附近脂肪，用滤纸吸去表面组织液，称各脏器湿重。计算李氏指数（李氏指数=（体重*1000/体长）1/3,体重单位:g，体长单位：cm）、脏器指数（脏器指数=脏器湿重*100/动物体重）和脂肪指数。采用试剂盒测定血清和肝脏TC、TG、HDL-C、LDL-C、瘦素、SOD、MDA、GSH-Px等的含量。
1.2.4 统计学分析
实验数据以（ ±s）表示，采用GraphPad Prism 5.0统计软件处理，采用单因素方差进行处理，以p<0.05为具有显著性意义。