Knockdown of amyloid precursor protein normalizes cholinergic function in a cell line derived from the cerebral cortex of a trisomy 16 mouse: An animal model of Down syndrome

Opazo, P; Saud, K; de Saint Pierre, M; Cárdenas AM; Allen, DD; Segura-Aguilar, J; Caviedes R.; Caviedes P.

Abstract

We have generated immortal neuronal cell lines from normal and trisomy 16 (Ts16) mice, a model for Down syndrome (DS). Ts16 lines overexpress DS-related genes (App, amyloid precursor protein; Sod1, Cu/Zn superoxide dismutase) and show altered cholinergic function (reduced choline uptake, ChAT expression and fractional choline release after stimulation). As previous evidence has related amyloid to cholinergic dysfunction, we reduced APP expression using specific mRNA antisense sequences in our neuronal cell line named CTb, derived from Ts16 cerebral cortex, compared to a cell line derived from a normal animal, named CNh. After transfection, Western blot studies showed APP expression knockdown in CTb cells of 36% (24 hr), 40.4% (48 hr), and 50.2% (72 hr) compared to CNh. Under these reduced APP levels, we studied 3H-choline uptake in CTb and CNh cells. CTb, as reported previously, expressed reduced choline uptake compared to CNh cells (75%, 90%, and 69% reduction at 1, 2, and 5 min incubation, respectively). At 72 hr of APP knockdown, choline uptake levels were essentially similar in both cell types. Further, fractional release of 3H-choline in response to glutamate, nicotine, and depolarization with KCl showed a progressive increase after APP knockdown, reaching values similar to those of CNh after 72 hr of transfection. The results suggest that APP overexpression in CTb cells contributes to impaired cholinergic function, and that gene knockdown in CTb cells is a relevant tool to study DS-related dysfunction. © 2006 Wiley-Liss, Inc.

Más información

Título según WOS: Knockdown of amyloid precursor protein normalizes cholinergic function in a cell line derived from the cerebral cortex of a trisomy 16 mouse: An animal model of Down syndrome
Título según SCOPUS: Knockdown of amyloid precursor protein normalizes cholinergic function in a cell line derived from the cerebral cortex of a trisomy 16 mouse: An animal model of Down syndrome
Título de la Revista: JOURNAL OF NEUROSCIENCE RESEARCH
Volumen: 84
Número: 6
Editorial: Wiley
Fecha de publicación: 2006
Página de inicio: 1303
Página final: 1310
Idioma: English
URL: http://doi.wiley.com/10.1002/jnr.21035
DOI:

10.1002/jnr.21035

Notas: ISI, SCOPUS