Review on Experimental Research of Herbal Medicines with Anti-Amnesic Activity

 

 Permissions and Reprints

Abstract

Amnesia is characterized by the inability to form memories or total or partial loss of memory secondary to cerebral malfunction following degenerative diseases, cerebral infections, traumatic injuries and emotional events which could be differentiated from dementia. However, no effective treatment for amnesia is currently available. Much research effort has been focused on developing new drugs from herbal medicines which have multifunctional properties. Novel plant extracts and their major or bioactive components including alkaloids, flavonoids, glycosides and saponins with promising antioxidant effects, various effects on cholinergic, GABAergic, glutaminergic, serotonergic, catecholaminergic and histaminergic systems, enhancement of cerebral blood flow and elevation of ribonucleic acid (RNA) as well as protein levels have been studied. In this review, we discuss the research findings on novel plant extracts and their bioactives with anti-amnesic effects on different neurotransmitter systems. Developing new drugs from herbal medicines for the treatment of amnesia is a hopeful attempt to meet the unmet medical needs.

References

• 1 Eysenck M W, Keane M T. Cognitive psychology: a student's handbook. New York; Psychology Press 2005
  PubMedGoogle Scholar
• 2 Cheng Y, Shen L H, Zhang J T. Anti-amnestic and anti-aging effects of ginsenoside Rg1 and Rb1 and its mechanism of action.  Acta Pharmacol Sin. 2005;  26 143-149
  CrossrefPubMedGoogle Scholar
• 3 Kennedy D O, Scholey A B. Ginseng: potential for the enhancement of cognitive performance and mood.  Pharmacol Biochem Behav. 2003;  75 687-700
  CrossrefPubMedGoogle Scholar
• 4 Nishijo H, Uwano T, Zhong Y M, Ono T. Proof of the mysterious efficacy of ginseng: basic and clinical trials: effects of red ginseng on learning and memory deficits in an animal model of amnesia.  J Pharmacol Sci. 2004;  95 145-152
  CrossrefPubMedGoogle Scholar
• 5 Blumenthal M, Busse W R. Bundesinstitut für Arzneimittel und Medizinprodukte .The complete German Commission E monographs: therapeutic guide to herbal medicines. Austin; American Botanical Council 1998
  PubMedGoogle Scholar
• 6 Heinrich M, Lee T H. Galanthamine from snowdrop – the development of a modern drug against Alzheimer's disease from local Caucasian knowledge.  J Ethnopharmacol. 2004;  92 147-162
  CrossrefPubMedGoogle Scholar
• 7 Erkinjuntti T, Kurz A, Gauthier S, Bullock R, Lilienfeld S, Damaraju C V. Efficacy of galantamine in probable vascular dementia and Alzheimer's disease combined with cerebrovascular disease: a randomised trial.  Lancet. 2002;  359 1283-1290
  CrossrefPubMedGoogle Scholar
• 8 Brown T H, Chapman P F, Kairiss E W, Keenan C L. Long-term synaptic potentiation.  Science. 1988;  242 724-728
  CrossrefPubMedGoogle Scholar
• 9 Centonze D, Picconi B, Gubellini P, Bernardi G, Calabresi P. Dopaminergic control of synaptic plasticity in the dorsal striatum.  Eur J Neurosci. 2001;  13 1071-1077
  CrossrefPubMedGoogle Scholar
• 10 Munro C A, Walling S G, Evans J H, Harley C W. Beta-adrenergic blockade in the dentate gyrus in vivo prevents high frequency-induced long-term potentiation of EPSP slope, but not long-term potentiation of population spike amplitude.  Hippocampus. 2001;  11 322-328
  CrossrefPubMedGoogle Scholar
• 11 Ohashi S, Matsumoto M, Otani H, Mori K, Togashi H, Ueno K, Kaku A, Yoshioka M. Changes in synaptic plasticity in the rat hippocampo-medial prefrontal cortex pathway induced by repeated treatments with fluvoxamine.  Brain Res. 2002;  949 131-138
  CrossrefPubMedGoogle Scholar
• 12 Yamazaki Y, Hamaue N, Sumikawa K. Nicotine compensates for the loss of cholinergic function to enhance long-term potentiation induction.  Brain Res. 2002;  946 148-152
  CrossrefPubMedGoogle Scholar
• 13 Myhrer T. Neurotransmitter systems involved in learning and memory in the rat: a meta-analysis based on studies of four behavioral tasks.  Brain Res Brain Res Rev. 2003;  41 268-287
  CrossrefPubMedGoogle Scholar
• 14 Quartermain D, Leo P. Strength of scopolamine-induced amnesia as a function of time between training and testing.  Behav Neural Biol. 1988;  50 300-310
  PubMedGoogle Scholar
• 15 Hatakeyama D, Sadamoto H, Watanabe T, Wagatsuma A, Kobayashi S, Fujito Y, Yamashita M, Sakakibara M, Kemenes G, Ito E. Requirement of new protein synthesis of a transcription factor for memory consolidation: paradoxical changes in mRNA and protein levels of C/EBP.  J Mol Biol. 2006;  356 569-577
  CrossrefPubMedGoogle Scholar
• 16 Barraco R A, Stettner L J. Antibiotics and memory.  Psychol Bull. 1976;  83 242-302
  CrossrefPubMedGoogle Scholar
• 17 Davis H P, Squire L R. Protein synthesis and memory: a review.  Psychol Bull. 1984;  96 518-559
  CrossrefPubMedGoogle Scholar
• 18 Ichihara K, Nabeshima T, Kameyama T. Opposite effects induced by low and high doses of apomorphine on single-trial passive avoidance learning in mice.  Pharmacol Biochem Behav. 1988;  30 107-113
  CrossrefPubMedGoogle Scholar
• 19 Ogren S O, Johansson C. Separation of the associative and non-associative effects of brain serotonin released by p-chloroamphetamine: dissociable serotoninergic involvement in avoidance learning, pain and motor function.  Psychopharmacology (Berlin). 1985;  86 12-26
  CrossrefPubMedGoogle Scholar
• 20 Levin E D, Briggs S J, Christopher N C, Auman J T. Working memory performance and cholinergic effects in the ventral tegmental area and substantia nigra.  Brain Res. 1994;  657 165-170
  CrossrefPubMedGoogle Scholar
• 21 Nooshinfar E, Lashgari R, Haghparast A, Sajjadi S. NMDA receptors are involved in Ginkgo extract-induced facilitation on memory retention of passive avoidance learning in rats.  Neurosci Lett. 2008;  432 206-211
  CrossrefPubMedGoogle Scholar
• 22 Hagan J J, Salamone J D, Simpson J, Iversen S D, Morris R G. Place navigation in rats is impaired by lesions of medial septum and diagonal band but not nucleus basalis magnocellularis.  Behav Brain Res. 1988;  27 9-20
  CrossrefPubMedGoogle Scholar
• 23 Hodges H, Allen Y, Kershaw T, Lantos P L, Gray J A, Sinden J. Effects of cholinergic-rich neural grafts on radial maze performance of rats after excitotoxic lesions of the forebrain cholinergic projection system – I. Amelioration of cognitive deficits by transplants into cortex and hippocampus but not into basal forebrain.  Neuroscience. 1991;  45 587-607
  CrossrefPubMedGoogle Scholar
• 24 Wenk G L, Cribbs B, McCall L. Nucleus basalis magnocellularis: optimal coordinates for selective reduction of choline acetyltransferase in frontal neocortex by ibotenic acid injections.  Exp Brain Res. 1984;  56 335-340
  PubMedGoogle Scholar
• 25 Hasselmo M E, Giocomo L M. Cholinergic modulation of cortical function.  J Mol Neurosci. 2006;  30 133-135
  CrossrefPubMedGoogle Scholar
• 26 Doods H N, Quirion R, Mihm G, Engel W, Rudolf K, Entzeroth M, Schiavi G B, Ladinsky H, Bechtel W D, Ensinger H A. Therapeutic potential of CNS-active M2 antagonists: novel structures and pharmacology.  Life Sci. 1993;  52 497-503
  CrossrefPubMedGoogle Scholar
• 27 Hammel P, Larrey D, Bernuau J, Kalafat M, Freneaux E, Babany G, Degott C, Feldmann G, Pessayre D, Benhamou J P. Acute hepatitis after tetrahydroaminoacridine administration for Alzheimer's disease.  J Clin Gastroenterol. 1990;  12 329-331
  CrossrefPubMedGoogle Scholar
• 28 Watkins P B, Zimmerman H J, Knapp M J, Gracon S I, Lewis K W. Hepatotoxic effects of tacrine administration in patients with Alzheimer's disease.  JAMA. 1994;  271 992-998
  CrossrefPubMedGoogle Scholar
• 29 Ohta H, Ni J W, Matsumoto K, Watanabe H, Shimizu M. Peony and its major constituent, paeoniflorin, improve radial maze performance impaired by scopolamine in rats.  Pharmacol Biochem Behav. 1993;  45 719-723
  CrossrefPubMedGoogle Scholar
• 30 Kang S Y, Lee K Y, Park M J, Kim Y C, Markelonis G J, Oh T H. Decursin from Angelica gigas mitigates amnesia induced by scopolamine in mice.  Neurobiol Learn Mem. 2003;  79 11-18
  CrossrefPubMedGoogle Scholar
• 31 Kim D H, Kim D Y, Kim Y C, Jung J W, Lee S, Yoon B H, Cheong J H, Kim Y S, Kang S S, Ko K H. Nodakenin, a coumarin compound, ameliorates scopolamine-induced memory disruption in mice.  Life Sci. 2007;  80 1944-1950
  CrossrefPubMedGoogle Scholar
• 32 Murakami A, Gao G, Kim O K, Omura M, Yano M, Ito C, Furukawa H, Jiwajinda S, Koshimizu K, Ohigashi H. Identification of coumarins from the fruit of Citrus hystrix DC as inhibitors of nitric oxide generation in mouse macrophage RAW 264.7 cells.  J Agric Food Chem. 1999;  47 333-339
  CrossrefPubMedGoogle Scholar
• 33 Cho J, Yang C H, Park C G, Lee H, Kim Y H. Inhibition of excitotoxic neuronal cell death by total extracts from oriental medicines used for stroke treatment.  Yakhak Hoeji. 2000;  44 29-35
  PubMedGoogle Scholar
• 34 Lee B, Choi Y, Kim H, Kim S Y, Hahm D H, Lee H J, Shim I. Protective effects of methanol extract of Acori graminei rhizoma and Uncariae Ramulus et Uncus on ischemia-induced neuronal death and cognitive impairments in the rat.  Life Sci. 2003;  74 435-450
  CrossrefPubMedGoogle Scholar
• 35 Irie Y, Keung W M. Rhizoma acori graminei and its active principles protect PC-12 cells from the toxic effect of amyloid-beta peptide.  Brain Res. 2003;  963 282-289
  CrossrefPubMedGoogle Scholar
• 36 Kim J H, Hahm D H, Lee H J, Pyun K H, Shim I. Acori graminei rhizoma ameliorated ibotenic acid-induced amnesia in rats.  Evid Based Complement Alternat Med. 2009;  6 457-464 DOI: 10.1093/ecam/nem158
  CrossrefPubMedGoogle Scholar
• 37 Hsieh M T, Wu C R, Lin L W, Hsieh C C, Tsai C H. Reversal caused by n-butylidenephthalide from the deficits of inhibitory avoidance performance in rats.  Planta Med. 2001;  67 38-42
  Article in Thieme ConnectPubMedGoogle Scholar
• 38 Hsieh M T, Tsai F H, Lin Y C, Wang W H, Wu C R. Effects of ferulic acid on the impairment of inhibitory avoidance performance in rats.  Planta Med. 2002;  68 754-756
  Article in Thieme ConnectPubMedGoogle Scholar
• 39 Peng W H, Hsieh M T, Wu C R. Effect of long-term administration of berberine on scopolamine-induced amnesia in rats.  Jpn J Pharmacol. 1997;  74 261-266
  CrossrefPubMedGoogle Scholar
• 40 Hung T M, Ngoc T M, Youn U J, Min B S, Na M, Thuong P T, Bae K. Anti-amnestic activity of pseudocoptisine from Corydalis tuber.  Biol Pharm Bull. 2008;  31 159-162
  CrossrefPubMedGoogle Scholar
• 41 Hsieh M T, Hsieh C L, Wang W H, Chen C S, Lin C J, Wu C R. Osthole improves aspects of spatial performance in ovariectomized rats.  Am J Chin Med. 2004;  32 11-20
  PubMedGoogle Scholar
• 42 Joshi H, Parle M. Antiamnesic effects of Desmodium gangeticum in mice.  Yakugaku Zasshi. 2006;  126 795-804
  CrossrefPubMedGoogle Scholar
• 43 Joshi H, Parle M. Cholinergic basis of memory-strengthening effect of Foeniculum vulgare Linn.  J Med Food. 2006;  9 413-417
  CrossrefPubMedGoogle Scholar
• 44 Lima J A, Costa R S, Epifanio R A, Castro N G, Rocha M S, Pinto A C. Geissospermum vellosii stembark: anticholinesterase activity and improvement of scopolamine-induced memory deficits.  Pharmacol Biochem Behav. 2009;  92 508-513
  CrossrefPubMedGoogle Scholar
• 45 Das A, Shanker G, Nath C, Pal R, Singh S, Singh H. A comparative study in rodents of standardized extracts of Bacopa monniera and Ginkgo biloba: anticholinesterase and cognitive enhancing activities.  Pharmacol Biochem Behav. 2002;  73 893-900
  CrossrefPubMedGoogle Scholar
• 46 Cheng D H, Ren H, Tang X C. Huperzine A, a novel promising acetylcholinesterase inhibitor.  Neuroreport. 1996;  8 97-101
  CrossrefPubMedGoogle Scholar
• 47 Wu C R, Lin L W, Wang W H, Hsieh M T. The ameliorating effects of LiuWei Dihuang Wang on cycloheximide-induced impairment of passive avoidance performance in rats.  J Ethnopharmacol. 2007;  113 79-84
  CrossrefPubMedGoogle Scholar
• 48 Hsieh M T, Cheng S J, Lin L W, Wang W H, Wu C R. The ameliorating effects of acute and chronic administration of LiuWei Dihuang Wang on learning performance in rodents.  Biol Pharm Bull. 2003;  26 156-161
  CrossrefPubMedGoogle Scholar
• 49 Tsai F S, Peng W H, Wang W H, Wu C R, Hsieh C C, Lin Y T, Feng I C, Hsieh M T. Effects of luteolin on learning acquisition in rats: involvement of the central cholinergic system.  Life Sci. 2007;  80 1692-1698
  CrossrefPubMedGoogle Scholar
• 50 Liu R, Gao M, Qiang G F, Zhang T T, Lan X, Ying J, Du G H. The anti-amnesic effects of luteolin against amyloid beta(25–35) peptide-induced toxicity in mice involve the protection of neurovascular unit.  Neuroscience. 2009;  162 1232-1243
  CrossrefPubMedGoogle Scholar
• 51 Vasudevan M, Parle M. Antiamnesic potential of Murraya koenigii leaves.  Phytother Res. 2009;  23 308-316
  CrossrefPubMedGoogle Scholar
• 52 Joshi H, Parle M. Nardostachys jatamansi improves learning and memory in mice.  J Med Food. 2006;  9 113-118
  CrossrefPubMedGoogle Scholar
• 54 Oh J H, Choi B J, Chang M S, Park S K. Nelumbo nucifera semen extract improves memory in rats with scopolamine-induced amnesia through the induction of choline acetyltransferase expression.  Neurosci Lett. 2009;  461 41-44
  CrossrefPubMedGoogle Scholar
• 55 Zhang D S, Zhang J T. Effect of total ginsenoside on synaptic transmission in dentate gyrus in rats.  Acta Pharmacol Sin. 2000;  35 185-188
  PubMedGoogle Scholar
• 56 Wang X Y, Zhang J T. Effects of ginsenoside Rg1 on synaptic plasticity of freely moving rats and its mechanism of action.  Acta Pharmacol Sin. 2001;  22 657-662
  PubMedGoogle Scholar
• 57 Zhang J T, Liu Y, Qu Z W, Zhang X L, Xiao H L. Influence of ginsenoside Rb1 and Rg1 on some central neurotransmitter receptors and protein biosynthesis in the mouse brain.  Yao Xue Xue Bao. 1988;  23 12-16
  PubMedGoogle Scholar
• 58 Zhang J T, Qu Z W, Liu Y, Deng H L. Preliminary study on antiamnestic mechanism of ginsenoside Rg1 and Rb1.  Chin Med J (Engl). 1990;  103 932-938
  PubMedGoogle Scholar
• 59 Jin S H, Park J K, Nam K Y, Park S N, Jung N P. Korean red ginseng saponins with low ratios of protopanaxadiol and protopanaxatriol saponin improve scopolamine-induced learning disability and spatial working memory in mice.  J Ethnopharmacol. 1999;  66 123-129
  CrossrefPubMedGoogle Scholar
• 60 Ikeya Y, Takeda S, Tunakawa M, Karakida H, Toda K, Yamaguchi T, Aburada M. Cognitive improving and cerebral protective effects of acylated oligosaccharides in Polygala tenuifolia.  Biol Pharm Bull. 2004;  27 1081-1085
  CrossrefPubMedGoogle Scholar
• 61 Hsieh M T, Kuo L H, Tsai F H, Wang W H, Wu C R. Effects of puerarin on scopolamine-, mecamylamine-, p-chloroamphetamine- and dizocilpine-induced inhibitory avoidance performance impairment in rats.  Planta Med. 2002;  68 901-905
  Article in Thieme ConnectPubMedGoogle Scholar
• 62 Heo H J, Suh Y M, Kim M J, Choi S J, Mun N S, Kim H K, Kim E, Kim C J, Cho H Y, Kim Y J, Shin D H. Daidzein activates choline acetyltransferase from MC-IXC cells and improves drug-induced amnesia.  Biosci Biotechnol Biochem. 2006;  70 107-111
  CrossrefPubMedGoogle Scholar
• 63 Kim D H, Jeon S J, Jung J W, Lee S, Yoon B H, Shin B Y, Son K H, Cheong J H, Kim Y S, Kang S S. Tanshinone congeners improve memory impairments induced by scopolamine on passive avoidance tasks in mice.  Eur J Pharmacol. 2007;  574 140-147
  CrossrefPubMedGoogle Scholar
• 64 Orhan I, Aslan M. Appraisal of scopolamine-induced antiamnesic effect in mice and in vitro antiacetylcholinesterase and antioxidant activities of some traditionally used Lamiaceae plants.  J Ethnopharmacol. 2009;  122 327-332
  CrossrefPubMedGoogle Scholar
• 65 Jeong E J, Lee K Y, Kim S H, Sung S H, Kim Y C. Cognitive-enhancing and antioxidant activities of iridoid glycosides from Scrophularia buergeriana in scopolamine-treated mice.  Eur J Pharmacol. 2008;  588 78-84
  CrossrefPubMedGoogle Scholar
• 66 Kim S R, Kang S Y, Lee K Y, Kim S H, Markelonis G J, Oh T H, Kim Y C. Anti-amnestic activity of E-p-methoxycinnamic acid from Scrophularia buergeriana.  Brain Res Cogn Brain Res. 2003;  17 454-461
  PubMedGoogle Scholar
• 67 Kim D H, Hung T M, Bae K H, Jung J W, Lee S, Yoon B H, Cheong J H, Ko K H, Ryu J H. Gomisin A improves scopolamine-induced memory impairment in mice.  Eur J Pharmacol. 2006;  542 129-135
  CrossrefPubMedGoogle Scholar
• 68 Vasudevan M, Parle M. Pharmacological actions of Thespesia populnea relevant to Alzheimer's disease.  Phytomedicine. 2006;  13 677-687
  CrossrefPubMedGoogle Scholar
• 69 Kim J H, Ha H C, Lee M S, Kang J I, Kim H S, Lee S Y, Pyun K H, Shim I. Effect of Tremella fuciformis on the neurite outgrowth of PC12 h cells and the improvement of memory in rats.  Biol Pharm Bull. 2007;  30 708-714
  CrossrefPubMedGoogle Scholar
• 70 Kim J H, Chung J Y, Lee Y J, Park S, Hahm D H, Lee H J, Shim I. Effects of methanol extract of Uncariae Ramulus et Uncus on ibotenic acid-induced amnesia in the rat.  J Pharmacol Sci. 2004;  96 314-323
  CrossrefPubMedGoogle Scholar
• 71 Prabhakar S, Saraf M K, Pandhi P, Anand A. Bacopa monniera exerts antiamnesic effect on diazepam-induced anterograde amnesia in mice.  Psychopharmacology (Berlin). 2008;  200 27-37
  CrossrefPubMedGoogle Scholar
• 72 Kim D H, Jeon S J, Son K H, Jung J W, Lee S, Yoon B H, Lee J J, Cho Y W, Cheong J H, Ko K H, Ryu J H. The ameliorating effect of oroxylin A on scopolamine-induced memory impairment in mice.  Neurobiol Learn Mem. 2007;  87 536-546
  CrossrefPubMedGoogle Scholar
• 73 Shors T J, Servatius R J, Thompson R F, Rogers G, Lynch G. Enhanced glutamatergic neurotransmission facilitates classical conditioning in the freely moving rat.  Neurosci Lett. 1995;  186 153-156
  CrossrefPubMedGoogle Scholar
• 74 Lynch G, Granger R, Ambros-Ingerson J, Davis C M, Kessler M, Schehr R. Evidence that a positive modulator of AMPA-type glutamate receptors improves delayed recall in aged humans.  Exp Neurol. 1997;  145 89-92
  CrossrefPubMedGoogle Scholar
• 75 Collingridge G L, Kehl S J, McLennan H. Excitatory amino acids in synaptic transmission in the Schaffer collateral-commissural pathway of the rat hippocampus.  J Physiol. 1983;  334 33-46
  PubMedGoogle Scholar
• 76 Nooshinfar E, Lashgari R, Haghparast A, Sajjadi S. NMDA receptors are involved in Ginkgo extract-induced facilitation on memory retention of passive avoidance learning in rats.  Neurosci Lett. 2008;  432 206-211
  CrossrefPubMedGoogle Scholar
• 77 Bao H Y, Zhang J, Yeo S J, Myung C S, Kim H M, Kim J M, Park J H, Cho J, Kang J S. Memory enhancing and neuroprotective effects of selected ginsenosides.  Arch Pharm Res. 2005;  28 335-342
  CrossrefPubMedGoogle Scholar
• 78 Lee S C, Linh P T, Jing Z, Ryu S Y, Myung C S, Kim Y H, Kang J S. Effects of repeated administration of Uncaria hooks on the acquisition and central neuronal activities in ethanol-treated mice.  J Ethnopharmacol. 2004;  94 123-128
  CrossrefPubMedGoogle Scholar
• 79 Barnes N M, Costall B, Naylor R J, Williams T J, Wischik C M. Normal densities of 5-HT3 receptor recognition sites in Alzheimer's disease.  Neuroreport. 1990;  1 253-254
  CrossrefPubMedGoogle Scholar
• 80 Hsieh M T, Wu C R, Wang W H, Lin L W. The ameliorating effect of the water layer of Fructus Schisandrae on cycloheximide-induced amnesia in rats: interaction with drugs acting at neurotransmitter receptors.  Pharmacol Res. 2001;  43 17-22
  CrossrefPubMedGoogle Scholar
• 81 Wu C R, Hsieh M T, Liao J. p-Hydroxybenzyl alcohol attenuates learning deficits in the inhibitory avoidance task: involvement of serotonergic and dopaminergic systems.  Chin J Physiol. 1996;  39 265-273
  PubMedGoogle Scholar
• 82 Hsieh M T, Wu C R, Hsieh C C. Ameliorating effect of p-hydroxybenzyl alcohol on cycloheximide-induced impairment of passive avoidance response in rats: interactions with compounds acting at 5-HT1A and 5-HT2 receptors.  Pharmacol Biochem Behav. 1998;  60 337-343
  CrossrefPubMedGoogle Scholar
• 83 Khalifa A E. Hypericum perforatum as a nootropic drug: enhancement of retrieval memory of a passive avoidance conditioning paradigm in mice.  J Ethnopharmacol. 2001;  76 49-57
  CrossrefPubMedGoogle Scholar
• 84 Lu M C, Hsieh M T, Wu C R, Cheng H Y, Hsieh C C, Lin Y T, Peng W H. Ameliorating effect of emodin, a constitute of Polygonatum multiflorum, on cycloheximide-induced impairment of memory consolidation in rats.  J Ethnopharmacol. 2007;  112 552-556
  CrossrefPubMedGoogle Scholar
• 85 Yamamoto Y, Adachi Y, Fujii Y, Kamei C. Ginkgo biloba extract improves spatial memory in rats mainly but not exclusively via a histaminergic mechanism.  Brain Res. 2007;  1129 161-165
  CrossrefPubMedGoogle Scholar
• 86 Kamei C, Tasaka K. Effect of histamine on memory retrieval in old rats.  Biol Pharm Bull. 1993;  16 128-132
  PubMedGoogle Scholar
• 87 Kamei C, Chung Y H, Tasaka K. Influence of certain H1-blockers on the step-through active avoidance response in rats.  Psychopharmacology (Berlin). 1990;  102 312-318
  CrossrefPubMedGoogle Scholar
• 88 Lee S C, Moon Y S, You K H. Effects of red ginseng saponins and nootropic drugs on impaired acquisition of ethanol-treated rats in passive avoidance performance.  J Ethnopharmacol. 2000;  69 1-8
  CrossrefPubMedGoogle Scholar
• 89 Wattanathorn J, Mator L, Muchimapura S, Tongun T, Pasuriwong O, Piyawatkul N, Yimtae K, Sripanidkulchai B, Singkhoraard J. Positive modulation of cognition and mood in the healthy elderly volunteer following the administration of Centella asiatica.  J Ethnopharmacol. 2008;  116 325-332
  CrossrefPubMedGoogle Scholar
• 90 Solomon P R, Adams F, Silver A, Zimmer J, DeVeaux R. Ginkgo for memory enhancement: a randomized controlled trial.  JAMA. 2002;  288 835-840
  CrossrefPubMedGoogle Scholar
• 91 DeKosky S T, Williamson J D, Fitzpatrick A L, Kronmal R A, Ives D G, Saxton J A, Lopez O L, Burke G, Carlson M C, Fried L P. Ginkgo biloba for prevention of dementia: a randomized controlled trial.  JAMA. 2008;  300 2253-2262
  CrossrefPubMedGoogle Scholar
• 92 Xu S S, Gao Z X, Weng Z, Du Z M, Xu W A, Yang J S, Zhang M L, Tong Z H, Fang Y S, Chai X S. Efficacy of tablet huperzine-A on memory, cognition, and behavior in Alzheimer's disease.  Zhongguo Yao Li Xue Bao. 1995;  16 391-395
  PubMedGoogle Scholar
• 93 Zhang Z, Wang X, Chen Q, Shu L, Wang J, Shan G. Clinical efficacy and safety of huperzine Alpha in treatment of mild to moderate Alzheimer disease, a placebo-controlled, double-blind, randomized trial.  Zhonghua Yi Xue Za Zhi. 2002;  82 941-944
  PubMedGoogle Scholar
• 94 Liang Y Q, Tang X C. Comparative effects of huperzine A, donepezil and rivastigmine on cortical acetylcholine level and acetylcholinesterase activity in rats.  Neurosci Lett. 2004;  361 56-59
  CrossrefPubMedGoogle Scholar
• 95 Debette S, Kozlowski O, Steinling M, Rousseaux M. Levodopa and bromocriptine in hypoxic brain injury.  J Neurol. 2002;  249 1678-1682
  CrossrefPubMedGoogle Scholar
• 96 Knecht S, Breitenstein C, Bushuven S, Wailke S, Kamping S, Floel A, Zwitserlood P, Ringelstein E B. Levodopa: faster and better word learning in normal humans.  Ann Neurol. 2004;  56 20-26
  CrossrefPubMedGoogle Scholar
• 97 Kandel E R. The molecular biology of memory storage: a dialog between genes and synapses.  Biosci Rep. 2001;  21 565-611
  CrossrefPubMedGoogle Scholar
• 98 Arnsten A F, Ramos B P, Birnbaum S G, Taylor J R. Protein kinase A as a therapeutic target for memory disorders: rationale and challenges.  Trends Mol Med. 2005;  11 121-128
  CrossrefPubMedGoogle Scholar
• 99 Baur J A, Pearson K J, Price N L, Jamieson H A, Lerin C, Kalra A, Prabhu V V, Allard J S, Lopez-Lluch G, Lewis K, Pistell P J, Poosala S, Becker K G, Boss O, Gwinn D, Wang M, Ramaswamy S, Fishbein K W, Spencer R G, Lakatta E G, Le Couteur D, Shaw R J, Navas P, Puigserver P, Ingram D K, de Cabo R, Sinclair D A. Resveratrol improves health and survival of mice on a high-calorie diet.  Nature. 2006;  444 337-342
  CrossrefPubMedGoogle Scholar
• 100 Reagan-Shaw S, Nihal M, Ahmad N. Dose translation from animal to human studies revisited.  FASEB J. 2008;  22 659-661
  CrossrefPubMedGoogle Scholar
• 101 Krebs N F. Bioavailability of dietary supplements and impact of physiologic state: infants, children and adolescents.  J Nutr. 2001;  131 1351S-1354S
  PubMedGoogle Scholar
• 102 Manach C, Williamson G, Morand C, Scalbert A, Remesy C. Bioavailability and bioefficacy of polyphenols in humans. I. Review of 97 bioavailability studies.  Am J Clin Nutr. 2005;  81 230S-242S
  CrossrefPubMedGoogle Scholar
• 103 Williamson G, Manach C. Bioavailability and bioefficacy of polyphenols in humans. II. Review of 93 intervention studies.  Am J Clin Nutr. 2005;  81 243S-255S
  PubMedGoogle Scholar
• 104 Youdim K A, Shukitt-Hale B, Joseph J A. Flavonoids and the brain: interactions at the blood-brain barrier and their physiological effects on the central nervous system.  Free Radic Biol Med. 2004;  37 1683-1693
  CrossrefPubMedGoogle Scholar
• 105 Raina P, Santaguida P, Ismaila A, Patterson C, Cowan D, Levine M, Booker L, Oremus M. Effectiveness of cholinesterase inhibitors and memantine for treating dementia: evidence review for a clinical practice guideline.  Ann Intern Med. 2008;  148 379-397
  CrossrefPubMedGoogle Scholar
• 106 Hsieh M T, Hsieh C L, Lin L W, Wu C R, Huang G S. Differential gene expression of scopolamine-treated rat hippocampus-application of cDNA microarray technology.  Life Sci. 2003;  73 1007-1016
  CrossrefPubMedGoogle Scholar
• 107 Brouillette J, Young D, During M J, Quirion R. Hippocampal gene expression profiling reveals the possible involvement of Homer1 and GABA(B) receptors in scopolamine-induced amnesia.  J Neurochem. 2007;  102 1978-1989
  CrossrefPubMedGoogle Scholar
• 108 Decker M. Recent advances in the development of hybrid molecules/designed multiple compounds with antiamnesic properties.  Mini Rev Med Chem. 2007;  7 221-229
  CrossrefPubMedGoogle Scholar

Dr. Hong Xi Xu

Hong Kong Jockey Club Institute of Chinese Medicine
Unit 703, 7/F
Bio-Informatics Centre
Hong Kong Science Park

Shatin

Hong Kong

People's Republic of China

Phone: + 85 2 34 06 28 73

Fax: + 85 2 35 51 73 33

Email: xuhongxi@hkjcicm.org