title: Ginsenoside Rb1 improves spatial learning and memory by regulation of cell genesis in the hippocampal subregions of rats.
abstract: Ginsenoside Rb1 (Rb1) is known to improve learning and memory in hippocampus-dependent tasks. However, the cellular mechanism remains unknown. Cell genesis in hippocampus is involved in spatial learning and memory. In the present study, Rb1 was orally administrated to adult rats for 30days. The behavioral training tests indicated that Rb1 improved spatial cognitive performance of rats in Morris water maze (MWM). Furthermore, we investigated the effects of Rb1 on cell genesis in adult rats' hippocampus, using thymidine analog bromodeoxyuridine (BrdU) as a marker for dividing cells. It has been shown that hippocampal cell genesis can be influenced by several factors such as learning and exercise. In order to avoid the effects of the interfering factors, only the rats treated with Rb1 without training in MWM were used to investigate cell genesis in hippocampus. When BrdU was given to the rats 30days prior to being killed, it was shown that oral administration of Rb1 significantly increased cell survival in dentate gyrus and hippocampal subregion CA3. However, when BrdU was injected 2h prior to sacrifice, the results indicated that Rb1 had no significant influence on cell proliferation in the hippocampal subregions. Thus, an increase of cell survival in hippocampus stimulated by Rb1 may be one of the mechanisms by which ginseng facilitates spatial learning and memory. Our study also indicates that Rb1 may be developed as a therapeutic agent for patients with memory impairment.
authors.affiliation: Department of Food Science and Technology, College of Agriculture and Biotechnology, Chungnam National University, Daejon 305-764, Republic of Korea.
authors.forename: Lei
authors.initials: L
authors.lastname: Liu
authors.forename: Trinh
authors.initials: T
authors.lastname: Hoang-Gia
authors.forename: Hui
authors.initials: H
authors.lastname: Wu
authors.forename: Mi-Ra
authors.initials: MR
authors.lastname: Lee
authors.forename: Lijuan
authors.initials: L
authors.lastname: Gu
authors.forename: Chunyan
authors.initials: C
authors.lastname: Wang
authors.forename: Beom-Sik
authors.initials: BS
authors.lastname: Yun
authors.forename: Qijun
authors.initials: Q
authors.lastname: Wang
authors.forename: Shengquan
authors.initials: S
authors.lastname: Ye
authors.forename: Chang-Keun
authors.initials: CK
authors.lastname: Sung
mesh_terms: D000284:Administration, Oral; D000818:Animals; D003071:Cognition / Q000187:drug effects / Q000502:physiology; D018891:Dentate Gyrus / Q000187:drug effects / Q000502:physiology; D036145:Ginsenosides / Q000494:pharmacology* / Q000627:therapeutic use; D006624:Hippocampus / Q000187:drug effects* / Q000502:physiology; D007859:Learning Disabilities / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D018782:Maze Learning / Q000187:drug effects / Q000502:physiology; D008568:Memory / Q000187:drug effects / Q000502:physiology; D008569:Memory Disorders / Q000188:drug therapy* / Q000503:physiopathology; D058953:Neural Stem Cells / Q000187:drug effects / Q000378:metabolism; D055495:Neurogenesis / Q000187:drug effects* / Q000502:physiology; D018697:Nootropic Agents / Q000494:pharmacology / Q000627:therapeutic use; D005894:Panax / Q000737:chemistry*; D008517:Phytotherapy / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D036145:Ginsenosides; D018697:Nootropic Agents; C442759:ginsenoside Rb1