此研究旨在评估云南苦茶提取物1,3,4,9-四甲基尿酸（1,3,4,9-tetramethyl uric acid, TC）对糖尿病肾病小鼠的氧化应激的调节潜力。实验采用喂养高脂高糖饲料，腹腔注射氯化镉（CdCl2）12周建立糖尿病肾病动物模型，灌胃TC 28 d，评估其血清生化指标的变化；通过观察肾丙二醛（MDA）、脂质过氧化产物（LOOH）、蛋白羰基化（PCO）含量等氧化及超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、还原性谷胱甘肽（GSH）等非酶抗氧化剂活性的变化，研究镉对肾脏的氧化损伤程度及四甲基尿酸的作用效果。实验结果显示，损伤组血清中的TG、ALT、LDL-C水平上调明显，分别为空白组的1.88倍、2.39倍、以及2.86倍；组织中的氧化指标MDA、PCO、NO显著升高，分别为空白组的1.51、3.88以及2.03倍；抗氧化指标CAT、SOD、GSH在损伤组有明显的下调，仅为空白组的68.75%、77.59%、80.95%；给予TC保护药后，血清指标水平较损伤组减少，仅为损伤组的68.09%、49.09%、45.65%；其氧化指标含量较损伤组减少，仅为损伤组的82.14%、74.19%、64.94%；抗氧化水平与损伤组相比明显升高，分别为损伤组的1.41、1.20及1.12倍。说明镉致糖尿病肾病（Diabetic Nephropathy, DN）小鼠机体内的氧化和抗氧化之间的平衡，进而导致氧化压力的增加；TC通过提高抗氧化酶的活性，增强抗氧化系统的抗氧化能力，通过抗氧化应激反应和抗炎作用共同保护肾脏。

This wok was designed to assess the regulatory potential of Yunnan, a bitter tea extract 1, 3, 4, 9-tetramethyl uric acid (TC) for oxidative stress in diabetic nephropathy mice. The mices were feed by high-fat and high-sugar diet, intraperitoneal injection of cadmium chloride (CdCl2) for 12 weeks to establish an animal model of diabetic nephropathy, and TC for 28 days, to evaluate the changes of serum biochemical indicators. The kidney malondialdehyde (MDA), lipid Oxidation of plasma peroxidation products (LOOH), protein carboxylation (PCO), non-enzymatic antioxidant activities such as superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH) were analyzed to study the effect of cadmium on the degree of oxidative damage in the kidney and tetraethyl uric acid. The results showed that the levels of TG, ALT and LDL-C in the serum of the injury group were significantly up-regulated, 1.88 times, 2.39 times, and 2.86 times, respectively, compared with the blank group. The oxidative indexes MDA, PCO and NO in the tissue were significantly increased by 1.51, 3.88 and 2.03 times, respectively. The antioxidant indexes CAT, SOD and GSH were significantly down-regulated in the injury group, only 68.75%, 77.59%, and 80.95%, respectively. After given TC protective drug, the serum index level was only 68.09%, 49.09%, and 45.65% of that of the injury group; the oxidation index content was decreased to 82.14%, 74.19%, and 64.94% of that of the injury group, which was only; the antioxidant level decreased to 1.41, 1.20 and 1.12 times of that of the injury group. The balance between oxidation and anti-oxidation in cadmium-induced diabetic nephropathy (DN) mice, which leads to an increase in oxidative stress; TC enhanced the antioxidant capacity of antioxidant systems by increasing the activity of antioxidant enzymes. The kidneys were protected together by anti-oxidative stress and anti-inflammatory effects.

国家自然科学基金项目（81803698）；陕西省自然科学基础研究计划项目（2017J8079）