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目的:探讨辣木黄酮对糖尿病脑病（DE）大鼠认知功能障碍及神经病理指标的影响。方法:将60只雄性SD大鼠按照随机数字表法分为对照组、模型组、阳性药物组及辣木低、高剂量组，每组10只。高脂高糖饲料持续喂养1周后经腹腔注射链脲霉菌素（STZ）25 mg/kg建立糖尿病大鼠模型，72 h后尾静脉采血，以2次随机血糖均值≥16.67 mmol/L、尿糖持续阳性表明糖尿病模型制备成功；对照组给予常规饲料喂养。辣木低、高剂量组大鼠制模成功后，分别每日灌胃4.0 g/kg和8.0 g/kg辣木提取物（辣木黄酮）；阳性药物组每日灌胃0.48 g/kg吡拉西坦，模型组和对照组每日灌胃等量生理盐水，均每日1次，持续给药30 d。进行Morris水迷宫实验以评估大鼠认知功能障碍情况。于末次给药后12 h分离大鼠海马组织，采用免疫组化染色检测晚期糖基化终末产物受体（RAGE）和核转录因子- κB（NF-κB）表达情况；采用酶联免疫吸附试验（ELISA）检测乙酰胆碱酯酶（AChE）、晚期糖基化终末产物（AGE）和乙酰胆碱转移酶（ChAT）含量。结果:与对照组相比，模型组大鼠逃避潜伏期、探索距离明显延长，目标象限停留时间明显缩短，脑组织AChE和AGE水平显著升高，ChAT水平显著降低。Morris水迷宫实验显示：与模型组相比，辣木低、高剂量组第3天起大鼠逃避潜伏期（s：35.07±7.21、33.14±5.35比43.09±9.83，均n P<0.05）和缩短探索距离（m：8.32±4.23、8.10±4.97比13.02±3.67）均明显缩短（均n P<0.05），目标象限停留时间明显延长（s：35.12±3.12、41.53±8.37比23.15±4.89，均n P<0.01）。ELISA结果显示，与模型组比较，辣木低、高剂量组脑组织中AChE和AGE水平显著降低〔AChE（U/L）：180.22±12.03、142.67±20.56比205.27±25.14，AGE（μg/L）：439.10±25.19、428.27±19.14比501.28±21.53，均n P<0.05〕，ChAT水平显著升高（U/L：51.95±5.27、53.13±5.04比37.91±5.10，均n P<0.01）；辣木低、高剂量组组间AChE、AGE和ChAT水平比较差异均无统计学意义。免疫组化结果显示：制模后DE大鼠海马DG区RAGE、NF-κB阳性细胞明显增多，海马组织RAGE和NF-κB平均灰度值显著降低；与模型组比较，辣木低、高剂量组RAGE、NF-κB阳性细胞明显减少，海马组织RAGE和NF-κB平均灰度值显著升高〔RAGE（灰度值）：110.46±10.04、117.76±8.64比92.19±8.76，NF-κB（灰度值）：109.40±8.93、116.59±7.26比90.74±13.27，均n P<0.05〕；但辣木低、高剂量组间RAGE和NF-κB表达水平比较差异均无统计学意义。n 结论:辣木黄酮能明显改善DE大鼠认知功能障碍及记忆能力，改善海马组织病变状况，具有一定脑保护作用。“,”Objective:To investigate the effect of Moringa flavone on cognitive impairment and neuropathological indexes in diabetic encephalopathy (DE) rats.Methods:Sixty male Sprague-Dawley (SD) rats were divided into control group, model group, positive drug group, Moringa low-dose and high-dose groups according to the random number table method, with 10 rats in each group. Diabetic rat model was established by intraperitoneal injection of 25 mg/kg streptozotocin (STZ) after continuous feeding of high fat and high sugar diet for one week. Blood was collected from the tail vein after 72 hours, the mean value of twice random blood glucose was ≥ 16.67 mmol/L, and the continuous positive urine glucose showed that the diabetes model was successfully prepared. The control group was fed with conventional feed. After successful model establishment, the rats in the Moringa low and high dose groups were given 4.0 g/kg and 8.0 g/kg Moringa extract (Moringa flavone) by gavage everyday, the rats in the positive drug group were given piracetam 0.48 g/kg, and the rats in the model group and control group were given the same amount of normal saline once a day for 30 days. Morris water maze was used to evaluate the cognitive impairment of the rats. The hippocampus of the rats was harvested 12 hours after the last administration, and the advanced glycation end product receptor (RAGE) and nuclear factor-κB (NF-κB) were detected by immunohistochemistry. The contents of acetylcholinesterase (AChE), advanced glycation end product (AGE) and choline acetyl transferase (ChAT) were detected by enzyme linked immunosorbent assay (ELISA).Results:Compared with the control group, the escape latency and the exploration distance in model group were extended, target quadrant stay time was shortened, the levels of AChE and AGE in brain tissue were significantly increased, and ChAT level was significantly decreased. Morris water maze experiment showed that compared with the model group, in the Moringa low and high dose groups from the 3rd day, the escape latency (s: 35.07±7.21, 33.14±5.35 vs. 43.09±9.83, both n P < 0.05) and the exploration distance (m: 8.32±4.23, 8.10±4.97 vs. 13.02±3.67) were significantly shortened (both n P < 0.05). The target qauadrant stay time was extended (s: 35.12±3.12, 41.53±8.37 vs. 23.15±4.89, both n P < 0.01). The results of ELISA showed that compared with the model group, the levels of AChE and AGE in brain tissue of the Moringa low and high dose groups were significantly decreased [AChE (U/L): 180.22±12.03, 142.67±20.56 vs. 205.27±25.14, AGE (μg/L): 439.10±25.19, 428.27±19.14 vs. 501.28±21.53, all n P < 0.05], and the levels of ChAT were significantly increased (U/L: 51.95±5.27, 53.13±5.04 vs. 37.91±5.10, both n P < 0.01). There were no significant differences in AChE, AGE or ChAT between the Moringa low and high dose groups. The results of immunohistochemistry showed that the number of RAGE and NF-κB positive cells in DG area of hippocampus increased significantly, and the average gray values of RAGE and NF-κB decreased significantly. Compared with the model group, the RAGE and NF-κB positive cells in the Moringa low and high dose groups were significantly reduced, and the average gray values of RAGE and NF-κB in hippocampus were significantly increased [RAGE (gray value): 110.46±10.04, 117.76±8.64 vs. 92.19±8.76, NF-κB (gray value): 109.40±8.93, 116.59±7.26 vs. 90.74±13.27, all n P < 0.05]. There were no significant differences in the expressions of RAGE or NF-κB between the Moringa low and high dose groups.n Conclusion:Moringa flavonoids could obviously improve the cognitive dysfunction and memory ability of DE model rats, improve the pathological changes of hippocampus, and have a certain protective effect on brain.