One night’s bad sleep can raise levels ofalzheimer-related protein

Just one night of poor sleep can significantly increase levels of a toxic brain substance linked to Alzheimer’s disease, a study has found.

Researchers used a radioactive tracer to measure the build-up of amyloid-beta peptide in the brains of 20 volunteers aged 22 to 72 over the course of two nights.

For one of the nights, participants were allowed a restful period of sleep. For the other, they were sleep deprived.

Positron Emission Tomography (Pet) scans were used to track the tracer. They showed that restricting sleep to as little as five hours led to a “significant increase” in amyloid-beta burden in two brain regions vulnerable to damage in Alzheimer’s patients – the hippocampus, which plays a key role in memory, and the thalamus, which acts as a relay centre for motor and sensory nerve signals.

Amyloid-beta is a protein building block that accumulates in sticky “plaques” in the brains of people with Alzheimer’s, leading to the destructionofneurons.sleepmayplay a in a natural “waste disposal” system that clears potentially harmful material including amyloid-beta out of the brain, scientists believe.

The new findings are published in the journal Proceedings of the National Academy of Sciences.

The team wrote: “Our results highlight the relevance of good sleep hygiene for proper brain function and as a potential target for prevention of Alzheimer’s disease.”

Dr David Reynolds, chief scientific officer at the charity at Alzheimer’s Research UK, said the study strengthens “suggestions that sleep is important for limiting the build-up of this protein in the brain”.