The protective effect of dietary eicosapentaenoic acid against impairment of spatial cognition learning ability in rats infused with amyloid beta(1-40).
BACKGROUND
Amyloid beta (Abeta) peptide (1-40) can cause cognitive impairment.


METHODS
We investigated whether dietary preadministration of eicosapentaenoic acid (EPA) is conducive to cognition learning ability and whether it protects against the impairment of learning ability in rats infused with Abeta peptide (1-40) into the cerebral ventricle.


RESULTS
Dietary EPA administered to rats for 12 weeks before the infusion of Abeta into the rat brain significantly decreased the number of reference memory errors (RMEs) and working memory errors (WMEs), suggesting that chronic administration of EPA improves cognition learning ability in rats. EPA preadministered to the Abeta-infused rats significantly reduced the increase in the number of RMEs and WMEs, with concurrent proportional increases in the levels of corticohippocampal EPA and docosahexaenoic acid (DHA) and in the DHA/arachidonic acid molar ratio. Decrease in oxidative stress in these tissues was evaluated by determining the reactive oxygen species and lipid peroxide levels. cDNA microarray analysis revealed that altered genes included those that control synaptic signal transduction, cell communication, membrane-related vesicular transport functions, and enzymes and several other proteins.


CONCLUSIONS
The present study suggests that EPA, by acting as a precursor for DHA, ameliorates learning deficits associated with Alzheimer's disease and that these effects are modulated by the expression of proteins involved in neuronal plasticity.
Hashimoto
Michio
M
Department of Environmental Physiology, Shimane University Faculty of Medicine, Izumo, Shimane 693-8501, Japan. michio1@med.shimane-u.ac.jp
Hossain
Shahdat
S
Tanabe
Yoko
Y
Kawashima
Akiko
A
Harada
Tsuyoshi
T
Yano
Takashi
T
Mizuguchi
Kiyoshi
K
Shido
Osamu
O
D016229:Amyloid beta-Peptides / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D000818:Animals; D015118:Eicosapentaenoic Acid / Q000627:therapeutic use*; D008297:Male; D018782:Maze Learning / Q000187:drug effects*; D008568:Memory / Q000187:drug effects*; D010446:Peptide Fragments / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013028:Space Perception / Q000187:drug effects
D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C078592:amyloid beta-protein (1-40); D015118:Eicosapentaenoic Acid