New research conducted by UVA Health suggests that enhanced light sensitivity may contribute to sundowning in Alzheimer’s patients. Sundowning refers to the worsening of symptoms late in the day and can lead to sleep disruptions thought to accelerate the progression of the disease. The findings shed light on the disruptions of the biological clock seen in Alzheimer’s and could have valuable implications for the development of treatments and symptom management.
The researchers propose that light therapy might be an effective tool in managing the erratic sleep patterns caused by altered circadian rhythms in Alzheimer’s patients. Caregivers often struggle with these patterns, as the body’s natural daily cycle is disrupted. Understanding the effects of Alzheimer’s on the biological clock could also have implications for preventing the disease. Poor sleep quality later in life is considered a risk factor for Alzheimer’s, as the brain’s natural ability to cleanse itself of amyloid beta proteins, which form harmful tangles in Alzheimer’s, occurs during rest.
The team of researchers, led by Thaddeus Weigel and Heather Ferris, used a mouse model of Alzheimer’s to investigate the impact of light exposure alterations on the biological clock. The mice were essentially given jet lag, and their behavior was observed. The Alzheimer’s mice displayed a significantly faster adaptation to the time changes compared to the control group. According to the scientists, this rapid adjustment to changes in light is a result of heightened light sensitivity. Unlike in normal biological clocks, the adaptation in Alzheimer’s mice occurred unusually quickly.
Initially, the researchers suspected that neuroinflammation in the brain might be causing this effect. Microglia, immune cells that have recently become targets for developing Alzheimer’s treatments, were assessed. However, the scientists ruled out this hypothesis, determining that microglia did not affect how quickly the mice adapted. Mutant tau, an abnormal protein associated with Alzheimer’s, was also not responsible for the rapid adaptation observed.
The results suggest that the retina plays an important role in the enhanced light sensitivity seen in Alzheimer’s. This finding provides a promising avenue for further research and the development of new treatments, management strategies, and preventive measures for Alzheimer’s disease. According to Ferris, controlling the type and timing of light could be key to reducing circadian disruptions in Alzheimer’s.
The study was published in the scientific journal Frontiers in Aging Neuroscience and was supported by the National Institutes of Health, the Owens Family Foundation, and the Commonwealth of Virginia’s Alzheimer’s and Related Diseases Research Fund.
In conclusion, the recent research from UVA Health highlights the link between enhanced light sensitivity and sundowning in Alzheimer’s patients. The findings have important implications for the development of treatments, symptom management, and potentially preventing the disease. By understanding the effects of Alzheimer’s on the biological clock, researchers can explore new avenues for managing the disease and improving the quality of life for patients and caregivers alike. Light therapy emerges as a potential tool to help manage the disrupted sleep patterns caused by altered circadian rhythms in Alzheimer’s patients. As researchers continue to delve into this field, their goal is to develop light therapies that can slow down the progression of Alzheimer’s disease.
