No Cover Image

Journal article 155 views 22 downloads

Complex cognitive and motivational deficits precede motor dysfunction in the zQ175 (190 CAG repeat) Huntington's disease model

D.J. Harrison, P. Linehan, Y. Patel, Zubeyde Bayram-Weston Orcid Logo, A.E. Rosser, S.B. Dunnett, S.P. Brooks, M.J. Lelos

Experimental Neurology, Volume: 392, Issue: 115350, Start page: 115350

Swansea University Author: Zubeyde Bayram-Weston Orcid Logo

  • 70352.VoR.pdf

    PDF | Version of Record

    © 2025 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license.

    Download (5.27MB)

Abstract

Huntington's disease (HD) is a progressive, inherited neurodegenerative disorder characterised by motor, cognitive, and neuropsychiatric dysfunction for which several mouse models have been developed. Knock-in models, such as zQ175, retain the genetic context observed in people with HD by intro...

Full description

Published in: Experimental Neurology
ISSN: 0014-4886
Published: Elsevier BV 2025
Online Access: Check full text

URI: https://cronfa.swan.ac.uk/Record/cronfa70352
Abstract: Huntington's disease (HD) is a progressive, inherited neurodegenerative disorder characterised by motor, cognitive, and neuropsychiatric dysfunction for which several mouse models have been developed. Knock-in models, such as zQ175, retain the genetic context observed in people with HD by introducing CAG repeats into the native huntingtin gene. In this study, we conducted a comprehensive, longitudinal analysis of phenotypic changes in the zQ175 mouse, with a focus on exploring the emergence of complex cognitive processes. Our findings indicate that robust cognitive and motivational deficits precede motor dysfunction in this model, with some apparent sex differences. Specifically, male zQ175 mice were slower to habituate to a novel environment and they showed impaired sensorimotor gating, in comparison to female mice. By 12 weeks old, cognitive deficits were observed in zQ175 mice of both sexes on a Pavlovian classical conditioning task. Reduced motivation to work for reward was identified as early as 27 weeks, while attentional and visuospatial deficits were also detected in the 5-choice serial reaction time task. Implicit learning deficits were identified at 30 weeks. zQ175 mice were hypoactive at ∼24 weeks but became hyperactive by 60 weeks of age. Motor impairments emerged by 24 weeks for females and 48 weeks for males. Thus, we observed a wide range of cognitive deficits (attentional, visuospatial, sensorimotor, instrumental and implicit learning), as well as a gradual progression of motor changes. This detailed phenotypic timeline establishes the face validity of this model insofar as these mice present with complex neuropsychiatric and cognitive impairments that are evident in people with HD.
Keywords: Huntington's disease; zQ175; Mouse model; Cognition; Neuropsychiatric; Motor; Behaviour
College: Faculty of Medicine, Health and Life Sciences
Funders: This project was funded by CHDI (the Cure Huntington's Disease Initiative) charity, an MRC grant (MR/T033428/1), with support from the Hodge Centre for Translational Neuroscience.
Issue: 115350
Start Page: 115350