Nutrients. 2015 Oct 5;7(10):8413-23. doi: 10.3390/nu7105401.

Effects of Asiatic Acid on Spatial Working Memory and Cell Proliferation in the Adult Rat Hippocampus.

Sirichoat A¹, Chaijaroonkhanarak W², Prachaney P³, Pannangrong W^4,⁵, Leksomboon R⁶, Chaichun A⁷, Wigmore P⁸, Welbat JU^9,^10,¹¹.

Author information

1: Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. dek_saba@hotmail.com.
2: Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. cwunnee@kku.ac.th.
3: Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. parpra@kku.ac.th.
4: Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. wankun@kku.ac.th.
5: Center for Research and Development of Herbal Health Products, Khon Kaen University, Khon Kaen 40002, Thailand. wankun@kku.ac.th.
6: College of Medicine and Public Health Ubon Ratchathani University, Ubon Ratchathani 34190, Thailand. ratana_tlek@yahoo.com.
7: Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. anmcha@kku.ac.th.
8: School of Life Sciences, Medical School, Queen's Medical Centre, Nottingham University, Nottingham NG7 2UH, UK. peter.wigmore@nottingham.ac.uk.
9: Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. jariya@kku.ac.th.
10: Center for Research and Development of Herbal Health Products, Khon Kaen University, Khon Kaen 40002, Thailand. jariya@kku.ac.th.
11: Neuroscience Research and Development Group, Khon Kaen University, Khon Kaen 40002, Thailand. jariya@kku.ac.th.

Abstract

Asiatic acid is a pentacyclic triterpene from Centella asiatica. Previous studies have reported that asiatic acid exhibits antioxidant and neuroprotective activities in cell culture. It also prevents memory deficits in animal models. The objective of this study was to investigate the relationship between spatial working memory and changes in cell proliferation within the hippocampus after administration of asiatic acid to male Spraque-Dawley rats. Control rats received vehicle (propylene glycol) while treated rats received asiatic acid (30 mg/kg) orally for 14 or 28 days. Spatial memory was determined using the novel object location (NOL) test. In animals administered asiatic acid for both 14 and 28 days, the number of Ki-67 positive cells in the subgranular zone of the dentate gyrus was significantly higher than in control animals. This was associated with a significant increase in their ability to discriminate between novel and familiar object locations in a novel object discrimination task, a hippocampus-dependent spatial memory test. Administration of asiatic acid also significantly increased doublecortin (DCX) and Notch1 protein levels in the hippocampus. These findings demonstrate that asiatic acid treatment may be a potent cognitive enhancer which improves hippocampal-dependent spatial memory, likely by increasing hippocampal neurogenesis.