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Neurobiology of sleep disturbances in neurodegenerative disorders

Centre D'étude du Sommeil et Des Rythmes Biologiques, Hôpital du Sacré-Coeur de Montréal, 5400 Boul. Gouin Ouest, Montréal, Québec, H4J 1C5, Canada.
Current pharmaceutical design (Impact Factor: 3.29). 02/2008; 14(32):3430-45. DOI: 10.2174/138161208786549353
Source: PubMed

ABSTRACT This review presents sleep disturbances and their underlying pathophysiology in three categories of neurodegenerative disorders namely tauopathies, synucleinopathies, and Huntington's disease (HD) and prion-related diseases. Sleep abnormalities are a major and early feature of neurodegenerative disorders, especially for synucleinopathies, HD and prion-related diseases, in which the sleep-related brainstem regions are severely altered and impaired sooner than in most of the tauopathies. In synucleinopathies, HD and prion-related diseases, specific sleep disturbances, different from those observed in tauopathies, are considered as core manifestations of the disease and in some cases, as preclinical signs. For this reason, the evaluation of sleep components in these neurodegenerative disorders may be useful to make a diagnosis and to assess the efficacy of pharmacotherapy. Since sleep disruption may occur early in the course of neurodegeneration, sleep disturbance may serve as groundwork to study the efficacy of neuroprotective agents to prevent or delay the development of a full-blown neurodegenerative disorder. The cause of sleep disturbances in neurodegenerative disorders may be attributed to several factors, including age-related modifications, symptoms of the disease, comorbid conditions and the neurodegenerative process itself.

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    • "The effect of chronic sleep deprivation in enhancing Ab plaque deposition in the brain was confirmed in Tg2576 mice and the APPswe/PS1dE9 transgenic mice (Kang et al. 2009). Sleep deprivation is an essential feature in both OSA and neurodegenerative diseases (Gagnon et al. 2008; Raggi and Ferri 2010). Further, disturbances of endogenous circadian rhythms and associated sleep-wake cycle noted in sleep disorders are also very pronounced in AD patients (Onen and Onen 2003; Harper et al. 2005; Wu and Swaab 2007; Volicer et al. 2012). "
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    • "The effect of chronic sleep deprivation in enhancing Ab plaque deposition in the brain was confirmed in Tg2576 mice and the APPswe/PS1dE9 transgenic mice (Kang et al. 2009). Sleep deprivation is an essential feature in both OSA and neurodegenerative diseases (Gagnon et al. 2008; Raggi and Ferri 2010). Further, disturbances of endogenous circadian rhythms and associated sleep-wake cycle noted in sleep disorders are also very pronounced in AD patients (Onen and Onen 2003; Harper et al. 2005; Wu and Swaab 2007; Volicer et al. 2012). "
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    • "For this reason, Drs. Gagnon et al. [12] present sleep disturbances and their underlying pathophysiology in three categories of neurodegenerative disorders namely tauopathies, synucleinopathies, and prion-related diseases. The evaluation of sleep disturbances in these pathologies may be useful to make a diagnosis and to assess the efficacy of pharmacotherapy. "
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