title: Alteration of the sialylation pattern and memory deficits by injection of Aβ(25-35) into the hippocampus of rats.
abstract: Sialic acid in glycoconjugates participates in important cellular functions associated with normal development, growth, and communication. Therefore we evaluated the sialylation pattern and memory deficits caused by the injection of Aβ((25-35)) into the hippocampus (Hp) of rats. The eight-arm maze spatial-learning and memory test indicated that the injection of Aβ((25-35)) into subfield CA1 of the Hp impaired both learning and memory. The sialylation pattern was examined using sialic acid-specific lectins. Our results showed that Maackia amurensis agglutinin (MAA, specific for Neu5Acα2,3Gal) showed reactivity in the CA1 and dentate gyrus (DG) subfields of the Hp mainly in the group injected with vehicle, whereas Macrobrachium rosenbergii lectin (MRL, specific for Neu5,9,7Ac) and Sambucus nigra agglutinin (SNA, specific for Neu5Acα2,6Gal-GalNAc) had increased reactivity in the CA1 and DG subfields of the Hp in the Aβ((25-35))-injected group. The staining pattern of the antibody specific for polysialic acid (a linear homopolymer of α-2,8-linked sialic acid) increased in the CA1 and DG subfields of the Hp of the Aβ((25-35)) group compared to the control group. Our results suggest that injection of Aβ((25-35)) causes impairment in spatial memory and alters the sialylation pattern in response to compensatory reorganization and-or sprouting of dendrites and axons of the surviving neurons.
authors.affiliation: Laboratorio de Neurofarmacología, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico.
authors.forename: Ilhuicamina Daniel
authors.initials: ID
authors.lastname: Limón
authors.forename: Eleazar
authors.initials: E
authors.lastname: Ramírez
authors.forename: Alfonso
authors.initials: A
authors.lastname: Díaz
authors.forename: Liliana
authors.initials: L
authors.lastname: Mendieta
authors.forename: Miguel Ángel
authors.initials: MÁ
authors.lastname: Mayoral
authors.forename: Blanca
authors.initials: B
authors.lastname: Espinosa
authors.forename: Jorge
authors.initials: J
authors.lastname: Guevara
authors.forename: Edgar
authors.initials: E
authors.lastname: Zenteno
mesh_terms: D000544:Alzheimer Disease / Q000378:metabolism / Q000473:pathology / Q000523:psychology*; D016229:Amyloid beta-Peptides / Q000502:physiology* / Q000633:toxicity; D000818:Animals; D056547:CA1 Region, Hippocampal / Q000378:metabolism / Q000473:pathology; D018891:Dentate Gyrus / Q000378:metabolism / Q000473:pathology; D004195:Disease Models, Animal; D006624:Hippocampus / Q000378:metabolism* / Q000473:pathology; D007276:Injections, Intraventricular; D008297:Male; D018782:Maze Learning; D008569:Memory Disorders / Q000378:metabolism / Q000473:pathology / Q000523:psychology*; D009474:Neurons / Q000473:pathology; D010446:Peptide Fragments / Q000502:physiology* / Q000633:toxicity; D051381:Rats; D017208:Rats, Wistar; D012794:Sialic Acids / Q000378:metabolism*
chemical_list: D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; D012794:Sialic Acids; C074636:amyloid beta-protein (25-35)