Medical University of Plovdiv, Plovdiv, Bulgaria.
Folia Med (Plovdiv). 2021 Apr 30;63(2):203-212. doi: 10.3897/folmed.63.e53060.
The Ginkgo biloba L. tree is considered as one of the oldest species on Earth. It is known as a "living fossil" dating back approximately 200 million years. Both the leaves and seeds of this tree have been used for millennia in traditional Chinese medicine.
To study the phytochemical profile of Gingko biloba seed extract (GBSE) and its memory enhancing effects.
Liquid chromatography with mass detection (LC-MS) was performed for phytochemical analyses of the extracts. For the in vivo experiments, male Wistar rats were divided randomly into 5 groups (n=8): saline; piracetam; GBSE 50; 100, and 200 mg/kg b.w. Y-maze, T-maze, step-down passive avoidance and novel object recognition test (NORT) were performed. The observed parameters were: percentage of spontaneous alternations (% SA), working memory index, latency of reaction and recognition index, respectively. Statistical analysis was done using SPSS 19.
LC-MS analysis showed the presence of the flavonoids quercetin, kaempferol and isorhamnetin (as aglycones), the ginkgolides A, B, C, J, and bilobalide. In Y-maze task, the groups treated with 50 and 100 mg/kg of GBSE significantly increased the % SA during the memory test compared to saline (p<0.05). In T-maze test, the three experimental groups with GBSE significantly increased the working memory index in comparison with that of the control group (p<0.05). In step-down test, the animals receiving 100 mg/kg b.w. GBSE, notably increased the latency during both retention tests (p<0.05 and p<0.01, respectively). In NORT, only the animals with the middle dose of GBSE ameliorated the recognition index when compared to saline (p<0.05).
GBSE enhances spatial working memory, recognition memory, and short- and long-term recall in naïve rats due to the synergic effects of detected flavonoids and terpene lactones on brain functions. The brain structures involved are probably the hippocampus and prefrontal cortex.
银杏是地球上最古老的物种之一，被认为是“活化石”，可以追溯到大约 2 亿年前。银杏的叶子和种子在传统的中国医学中已经使用了几千年。
研究银杏种仁提取物（GBSE）的植物化学成分谱及其增强记忆的作用。
采用液相色谱-质谱联用（LC-MS）法对提取物进行植物化学成分分析。在体内实验中，雄性 Wistar 大鼠随机分为 5 组（n=8）：生理盐水；吡拉西坦；GBSE 50、100 和 200mg/kg 体重。进行 Y 迷宫、T 迷宫、跳下式被动回避和新物体识别测试（NORT）。观察的参数分别为：自发交替百分比（% SA）、工作记忆指数、反应潜伏期和识别指数。使用 SPSS 19 进行统计分析。
LC-MS 分析表明，存在槲皮素、山柰酚和异鼠李素（作为糖苷配基）、银杏内酯 A、B、C、J 和白果内酯。在 Y 迷宫任务中，与生理盐水组相比，50 和 100mg/kg 体重的 GBSE 处理组在记忆测试中显著增加了% SA（p<0.05）。在 T 迷宫测试中，与对照组相比，三个用 GBSE 处理的实验组显著增加了工作记忆指数（p<0.05）。在跳下式测试中，100mg/kg 体重的 GBSE 处理组动物在两个保留测试中显著增加了潜伏期（p<0.05 和 p<0.01）。在新物体识别测试中，只有中剂量的 GBSE 处理组的动物改善了识别指数与生理盐水相比（p<0.05）。
GBSE 通过检测到的类黄酮和三萜内酯对大脑功能的协同作用，增强了未接受过训练的大鼠的空间工作记忆、识别记忆以及短期和长期记忆。涉及的脑结构可能是海马体和前额叶皮层。
