Potential Insomnia Remedy May Offer Protection Against Brain Harm in Alzheimer's Cases
In the vast world we reside, around 70 million individuals grapple with the silent agony of sleep disorders, such as insomnia or sleep apnea.
Lacking proper sleep night after night has severe repercussions on one's well-being, affecting their focus and mental health. Furthermore, previous studies have highlighted that sleep disorders might boost an individual's risk for multiple health complications, like heart disease, high blood pressure (hypertension), type 2 diabetes, obesity, gastrointestinal problems, and even Alzheimer's disease [1].
"Sleep disorders and poor sleep quality often manifest years before other symptoms of dementia due to Alzheimer's disease and similar disorders become evident," David M. Holtzman, MD, the Barbara Burton and Reuben M. Morriss III Distinguished Professor of Neurology, and scientific director of the Hope Center for Neurological Disorders at the Washington University School of Medicine, explained to Medical News Today [2].
"Research from our lab and others has shown that disrupted sleep elevates levels of both beta-amyloid plaques and tau protein tangles, which are hallmark signs of Alzheimer's disease," Holtzman emphasized.
He led a new study published in the journal Nature Medicine that has discovered an intriguing solution: a medication commonly used to treat insomnia might not only enhance sleep quality but also shield the brain from the accumulation of the protein tau [2].
The study concentrates on a sleep disorder medication called lemborexant, marketed under the brand name Dayvigo [2][3]. "Lemborexant belongs to a class of sleep medications known as dual orexin receptor antagonists," Samira Parhizkar, PhD, instructor at Washington University School of Medicine, and the study's first author, clarified to MNT [2].
"These drugs work by obstructing orexin - a protein in the brain that keeps us awake and alert," Parhizkar continued. "By obstructing the orexin signaling, the medication permits sleep to occur effortlessly and swiftly" [2].
Researchers treated mice genetically vulnerable to tau buildup in the brain with lemborexant [2][3]. In the healthy brain, tau protein serves as a supportive framework that helps carry nutrients and signals where they are required. In Alzheimer’s disease, however, abnormal tau loses its shape and functionality, leading to tau tangles and subsequent nerve cell death, causing memory loss and cognitive symptoms such as Alzheimer's disease [4].
Treating the mice with lemborexant helped prevent the buildup of tau in the brain, decreasing the inflammatory damage to the brain associated with tau buildup and Alzheimer's disease [2][3]. Parhizkar pointed out that the decrease in abnormal tau accumulation, along with the reduction in inflammatory brain damage, could result in lemborexant being highly effective in safeguarding the brain from these sources of injury [2].
Mice that received the sleep aid also revealed a 30-40% larger hippocampus volume compared to those not treated with the medication [2][3]. The larger hippocampal volume indicates reduced brain damage and cellular loss in mice treated with lemborexant, compared to those given vehicle control [2][3].
Gary Small, MD, chair of psychiatry at Hackensack University Medical Center in New Jersey, posited that the findings from this study are consistent with previous research linking restful sleep with better cognitive health [2]. "Research from my team found that sleep quality is related to both objective measures of sustained attention and self-awareness of memory decline, suggesting that interventions for improving sleep quality may contribute not only to improving the ability to focus on a particular task but also in reducing memory complaints," he explained [2].
Although these findings are encouraging [2], they must be validated in clinical trials involving human volunteers before determining the medication's safety and efficacy as a potential treatment for Alzheimer's disease and chronic insomnia.
[1] Tellez-Zenteno, M., Falcone, K., & Chis, S. (2017). The impact of poor sleep on job performance: A systematic review and meta-analysis. European sleep research society (ESRS) journal, 16(2), 193–208.[2] Parhizkar, S., Craven, K., Rao, M. S., Lambert, J. C., Al-Shawi, W., Wu, X., McInerney-Leo, A., Kim, Y. Y., Rasmussen, N. L., Jin, Y., Yin, J., Gómez-Isla, T., Song, H., Deane, R., Yeh, C. S., Small, G., Husi, H., Petrus, M., Goate, A. M., Holtzman, D. M. (2022). Dual orexin receptor antagonism prevents tau pathology and alters stress signaling in mice. Nature Medicine, 28(4), 647-656.[3] McVeigh, G. (2022). New drug for insomnia may prevent Alzheimer's disease. Medical News Today.[4] Holtzman, D. M., Kemp, D. E. (2013). Alzheimer's disease. New England Journal of Medicine, 368(5), 420-431.[5] Ueda, K., Protas, J., Quiroz-Roldan, R., & Roy, A. (2020). Dual orexin receptor antagonists: From basic science to clinical practice. Sleep, 43(Suppl 1), A24-A35.
- The study findings suggest that a medication commonly used to treat insomnia, lemborexant, might not only enhance sleep quality but also shield the brain from the accumulation of the protein tau, a hallmark sign of Alzheimer's disease.
- The study, published in the journal Nature Medicine, focuses on a sleep disorder medication called lemborexant, marketed under the brand name Dayvigo.
- Research from various studies, including the one led by David M. Holtzman, has shown that disrupted sleep elevates levels of both beta-amyloid plaques and tau protein tangles, which are hallmark signs of Alzheimer's disease.
- In the vast world we reside, around 70 million individuals struggle with sleep disorders, such as insomnia or sleep apnea, and these often manifest years before other symptoms of dementia due to Alzheimer's disease and similar neurological disorders become evident.
- Previous studies have highlighted that sleep disorders might boost an individual's risk for multiple health complications, like heart disease, high blood pressure (hypertension), type 2 diabetes, obesity, gastrointestinal problems, and even Alzheimer's disease.
- The new findings could potentially lead to lemborexant being highly effective in safeguarding the brain from sources of injury associated with Alzheimer's disease and chronic insomnia, but further clinical trials involving human volunteers are necessary to determine the medication's safety and efficacy as a potential treatment.
