title: Inhibitory effect of ethanol extract of Magnolia officinalis and 4-O-methylhonokiol on memory impairment and neuronal toxicity induced by beta-amyloid.
abstract: The components of the herb Magnolia officinalis have exhibited antioxidant and neuroprotective activities. In this study, we investigated effects of ethanol extract of M.officinalis and its major component 4-O-methylhonokiol on memory dysfunction and neuronal cell damages caused by A beta. Oral pretreatment of ethanol extract of M. officinalis (2.5, 5 and 10mg/kg) and 4-O-methylhonokiol (1mg/kg) into drinking water for 5 weeks suppressed the intraventricular treatment of A beta(1-42) (0.5 microg/mouse, i.c.v.)-induced memory impairments. In addition, 4-O-methylhonokiol prevented the A beta(1-42)-induced apoptotic cell death as well as beta-secretase expression. 4-O-methylhonokiol also inhibited H(2)O(2) and A beta(1-42)-induced neurotoxicity in cultured neurons as well as PC12 cells by prevention of the reactive oxygen species generation. 4-O-methylhonokiol also directly inhibited beta-secretase activity and A beta fibrilization in vitro. Thus, ethanol extract of M. officinalis may be useful for prevention of the development or progression of AD, and 4-O-methylhonokiol may be a major active component.
authors.affiliation: College of Pharmacy, Core Research Institute, Chungbuk National University, 12, Gaesin-dong, Heungduk-gu, Cheongju, Chungbuk 361-763, Republic of Korea.
authors.forename: Jae Woong
authors.initials: JW
authors.lastname: Lee
authors.forename: Yong Kyung
authors.initials: YK
authors.lastname: Lee
authors.forename: Beom Jun
authors.initials: BJ
authors.lastname: Lee
authors.forename: Sang-Yoon
authors.initials: SY
authors.lastname: Nam
authors.forename: Sang Il
authors.initials: SI
authors.lastname: Lee
authors.forename: Young Heui
authors.initials: YH
authors.lastname: Kim
authors.forename: Ki Ho
authors.initials: KH
authors.lastname: Kim
authors.forename: Ki-Wan
authors.initials: KW
authors.lastname: Oh
authors.forename: Jin Tae
authors.initials: JT
authors.lastname: Hong
mesh_terms: D000818:Animals; D001713:Biphenyl Compounds / Q000494:pharmacology*; D015153:Blotting, Western; D000431:Ethanol / Q000737:chemistry*; D005453:Fluorescence; D017705:Lignans / Q000494:pharmacology*; D031566:Magnolia / Q000737:chemistry*; D008297:Male; D008568:Memory / Q000187:drug effects*; D051379:Mice; D008813:Mice, Inbred ICR; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D016716:PC12 Cells; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: C542058:4-O-methylhonokiol; D001713:Biphenyl Compounds; D017705:Lignans; D010936:Plant Extracts; D017382:Reactive Oxygen Species; D000431:Ethanol