A study has shown that the sleeping pill suvorexant, not available on the French market, leads to a drop in the levels of Tau proteins, known to be involved in the development of Alzheimer’s disease.
- A small study, conducted over two nights with 38 volunteers, showed that people who took a sleeping pill before bed had lower levels of Tau proteins, which are known to promote the onset of Alzheimer’s disease.
- The sleeping pill tested was suvorexant. This product inhibits the action of orexin neurotransmitters which play an essential role in maintaining wakefulness. However, it is not on sale in France.
- The researchers indicate that further research is needed to confirm their results and lead to a possible use in the prevention of Alzheimer’s disease.
Suvorexant, sold under the Belsomra brand in several countries including the USA and Japan, is a new class of sleeping pills. It disables wakefulness – by blocking neurotransmitters called orexins – rather than inducing sleep. However, this treatment, which is not available on the French market, could have a much wider scope than insomnia. Researchers from the Washington University School of Medicine (St. Louis, USA) have discovered that the pills lead to a drop in the level of Tau proteins, a key element in Alzheimer’s disease.
Suvorexant linked to lower Tau protein
For this study, published in Annals of Neurology on April 20, 2023, the researchers brought together 38 participants aged 45 to 65, with no cognitive impairment. For two successive days, the volunteers received either a low dose (10 mg) of suvorexant, or a higher one (20 mg), or a placebo each evening at 9 p.m. A small amount of cerebrospinal fluid was collected by lumbar puncture every two hours for 36 hours, beginning one hour before treatment administration.
The team analyzed the samples to determine changes in beta-amyloid and T protein levels.hyperphosphorylated during the experience.
Beta-amyloid protein levels in people who took the highest dose of sleeping pills fell 10% to 20% compared to people who took the placebo. The drop was 10% to 15% for Tau protein hyperphosphorylated. “There was no significant difference between people who received a low dose of suvorexant and those who received the placebo”specifies the communicated.
Twenty-four hours after the first intake of the drug, the Tau proteins hyperphosphorylated increased while beta-amyloid levels remained low for the treatment group. The second dose, given on the second night, caused the levels of both proteins to fall again in people who had taken 20 mg of suvorexant.
“If we can reduce beta-amyloid protein every day, we believe the buildup of amyloid plaques in the brain will decrease over time”explained lead author Brendan Lucey. “The Tau protein hyperphosphorylated plays an important role in the development of Alzheimer’s disease, as it is associated with the formation of tau protein tangles that kill neurons. If you could reduce tau phosphorylation, there would potentially be less tangle formation and less neuronal death.”recalls the expert.
Alzheimer’s treatment: further studies needed
If the results of the American study are encouraging, the scientists advise against people who fear developing Alzheimer’s disease to start taking suvorexant every evening. They remind that this is a limited trial that requires further research.
“We don’t yet know if long-term use is effective in warding off cognitive decline, and if so, at what dose and for whom”, adds researcher Brendan Lucey. “Future studies need to get people on these drugs for months, at least, and measure the effect on amyloid and tau over time.”
The expert is hopeful of discovering drugs against cognitive decline that take advantage of the link between sleep and Alzheimer’s disease. However at this stage, “The best advice I can give you is to get a good night’s sleep if you can. And, if you can’t, see a specialist and get your sleep problems treated”he acknowledges.
