Gadahad Mohandas Rao Kappettu, Rao Muddanna, Rao Gurumadhva
Department of Anatomy, Melaka Manipal Medical College, Manipal, India.
J Chin Med Assoc. 2008 Jan;71(1):6-13. doi: 10.1016/s1726-4901(08)70066-2.
Centella asiatica (CeA) is a creeper, growing in moist places in India and other Asian countries. Leaves of CeA are used for memory enhancement in the Ayurvedic system of medicine, an alternate system of medicine in India. In the present study, we investigated the role of CeA fresh leaf extract treatment on the dendritic morphology of hippocampal CA3 neurons, one of the regions concerned with learning and memory, in adult rats.
In the present study, adult rats (2.5 months old) were fed with 2, 4 and 6 mL/kg body weight of fresh leaf extract of CeA for 2, 4 and 6 weeks, respectively. After the treatment period, the rats were killed, brains were removed and hippocampal neurons were impregnated with silver nitrate (Golgi staining). Hippocampal CA3 neurons were traced using camera lucida, and dendritic branching points (a measure of dendritic arborization) and intersections (a measure of dendritic length) were quantified. These data were compared with those of age-matched control rats.
The results showed a significant increase in the dendritic length (intersections) and dendritic branching points along the length of both apical and basal dendrites in rats treated with 6 mL/kg body weight/day of CeA for 6 weeks. However, the rats treated with 2 and 4 mL/kg body weight/day for 2 and 4 weeks did not show any significant change in hippocampal CA3 neuronal dendritic arborization.
We conclude that constituents present in Centella asiatica fresh leaf extract has neuronal dendritic growth-stimulating properties.
积雪草是一种蔓生植物，生长于印度和其他亚洲国家的潮湿地区。在印度替代医学阿育吠陀体系中，积雪草叶被用于增强记忆力。在本研究中，我们调查了积雪草鲜叶提取物处理对成年大鼠海马CA3神经元树突形态的作用，海马CA3神经元是与学习和记忆相关的脑区之一。
在本研究中，成年大鼠（2.5月龄）分别以2、4和6 mL/kg体重的积雪草鲜叶提取物喂养2、4和6周。处理期结束后，处死大鼠，取出大脑，用硝酸银对海马神经元进行浸染（高尔基染色）。使用显微镜描绘海马CA3神经元，对树突分支点（衡量树突分支的指标）和交叉点（衡量树突长度的指标）进行量化。将这些数据与年龄匹配的对照大鼠的数据进行比较。
结果显示，以6 mL/kg体重/天的积雪草提取物处理6周的大鼠，其顶树突和基底树突长度（交叉点）以及沿树突长度的树突分支点均显著增加。然而，以2和4 mL/kg体重/天处理2和4周的大鼠，海马CA3神经元树突分支未显示任何显著变化。
我们得出结论，积雪草鲜叶提取物中的成分具有刺激神经元树突生长的特性。
