title: Gypenoside TN-2 ameliorates scopolamine-induced learning deficit in mice.
abstract: BACKGROUND
  Gynostemma pentaphyllum (Thunb.) Makino (GP, family Cucurbitaceae), which contains dammarane saponins as its main constituents, is used in China, Japan, and Korea as a traditional medicine to treat cancer, obesity, arteriosclerosis, asthma and senility.
  
  
  OBJECTIVE
  To investigate the memory-enhancing effects of GP, Gypenoside TN-2 (TN-2) was isolated by activity-guided fractionation and administered to scopolamine-induced memory-deficient mice.
  
  
  METHODS
  The memory-enhancing effects of TN-2 were evaluated using passive avoidance, Y-maze, and Morris water maze tests, and the protein expressions of brain-derived neurotrophic factor (BDNF), cAMP element binding protein (CREB), and p-CREB were determined by immunoblotting.
  
  
  RESULTS
  TN-2 inhibited memory and learning deficits in scopolamine treated mice in the passive avoidance test. TN-2 (10, 20, and 40 mg/kg, p.o.) significantly inhibited memory and learning deficits in the passive avoidance test by 40%, 96% and 78%, respectively, and exhibited significant memory-enhancing effects on the Y-maze test and the Morris water maze test. TN-2 also markedly increased BNDF expression and activated the transcription factor CREB in the hippocampi of scopolamine-treated mice.
  
  
  CONCLUSIONS
  TN-2 may ameliorate memory and learning deficits by activating the CREB-BDNF pathway.
authors.affiliation: Department of Life and Nanopharmaceutical Sciences, Kyung Hee University, Hoeki-dong, Dongdaemoon-ku, Seoul 130-701, Republic of Korea.
authors.forename: Sung-Woon
authors.initials: SW
authors.lastname: Hong
authors.forename: Jeong-Hwa
authors.initials: JH
authors.lastname: Yang
authors.forename: Eun-Ha
authors.initials: EH
authors.lastname: Joh
authors.forename: Hyoung Ja
authors.initials: HJ
authors.lastname: Kim
authors.forename: Dong-Hyun
authors.initials: DH
authors.lastname: Kim
mesh_terms: D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D029774:Gynostemma; D007859:Learning Disabilities / Q000139:chemically induced / Q000188:drug therapy*; D008297:Male; D018782:Maze Learning; D051379:Mice; D008813:Mice, Inbred ICR; D010936:Plant Extracts / Q000627:therapeutic use; D012601:Scopolamine / Q000633:toxicity*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D010936:Plant Extracts; C474918:gypenoside; D012601:Scopolamine