Brain Protein Indicates a Link Between Circadian Rhythm Dysfunction and Alzheimer's Disease

A study in Science Translational Medicine suggests the brain protein YKL-40 may contain a clue into a possible connection between Alzheimer's disease and circadian dysfunction, reports News-Medical . According to the researchers, YKL-40 is both regulated by clock genes and plays a role in clearing away potentially toxic accumulation of Alzheimer's proteins in the brain. Furthermore, Alzheimer's patients who carry a genetic variant that reduces YKL-40 levels maintain their cognitive faculties longer than people without it. "If your circadian clock is not quite right for years and years, you routinely suffer from disrupted sleep at night and napping during the day; the cumulative effect of chronic 'dysregulation' could influence inflammatory pathways such that you accumulate more amyloid plaques," said Washington University in St. Louis professor Erik Musiek. "Amyloid plaques in the brain are one of the early hallmarks of Alzheimer's disease."