Summary
Huntington's disease disrupts circadian clock gene expression (mPer2, mBmal1) in the SCN, leading to fragmented day-night activity cycles that worsen with disease progression. Circadian-supportive lighting interventions targeting SCN entrainment may offer a therapeutic avenue to improve sleep quality and quality of life for HD patients and their caregivers.
Key Findings
- R6/2 transgenic HD mice showed progressive disintegration of circadian behavior, with increased daytime activity and reduced nocturnal activity mirroring patterns seen in HD patients.
- mPer2 circadian peak expression was prematurely truncated and mBmal1 mRNA levels were attenuated and lost significant circadian oscillation in the SCN of R6/2 mice.
- Circadian gene expression cycles in the motor cortex and striatum were suppressed in R6/2 mice, providing a neural correlate of disrupted activity rhythms.
- Reduced SCN expression of prokineticin 2 (a transcriptional target of mBmal1 that suppresses daytime activity) was associated with increased daytime activity in HD mice.
Categories
Sleep & Circadian Health: Reviews circadian rhythm disruption and sleep disorders specifically in Huntington's disease, including clock gene dysfunction.
Dementia & Elder Care: Addresses neurodegeneration-related circadian disruption relevant to management of HD patients in care settings.
The Science of Light: Implicates SCN molecular oscillation (mPer2, mBmal1, prokineticin 2) as the mechanistic basis for circadian disruption, relevant to light-based entrainment strategies.
Author(s)
S Saade-Lemus, A Videnovic
Publication Year
2023
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