Scientists discover brain cells that clear Alzheimer’s proteins

The study focuses on tanycytes, cells lining the brain’s third ventricle that are in direct contact with both the bloodstream and cerebrospinal fluid. Because of this unique position, they can bypass the blood–brain barrier and transport molecules in and out of the brain “Tanycytes are highways for the brain,” said Vincent Prévot, a neuroendocrinologist at Inserm in Paris Scientists discovered that tanycytes can move harmful tau proteins from the cerebrospinal fluid into the bloodstream, effectively helping the brain clear these substances. Abnormal accumulation of tau proteins is one of the hallmarks of Alzheimer’s disease Tau proteins normally support the internal structure of cells, including neurons. However, in people with Alzheimer’s disease, the proteins become dysfunctional and form sticky clumps that damage brain cells and impair memory In experiments with mice, researchers injected fluorescently tagged human tau proteins into the cerebrospinal fluid and observed that tanycytes transported the proteins through the pituitary gland and into the bloodstream When tanycytes were impaired, tau accumulated in the brain while levels in the bloodstream dropped, suggesting the cells play a key role in removing the protein The team also analyzed samples from 86 people with Alzheimer’s disease and 91 individuals without the condition. They found significantly less movement of tau proteins from the cerebrospinal fluid to the bloodstream in patients with the disease, indicating malfunctioning tanycytes “It’s like you had taken some scissors and cut them 100 times,” Prévot said, describing how damaged these cells appeared in brain-tissue samples Scientists say further research could explore whether improving tanycyte function may help reduce the risk of Alzheimer’s disease Earlier, Qazinform International News Agency reported that the Ministry of Healthcare of Kazakhstan is steadily introducing AI-based solutions to improve diagnostic accuracy, support clinical decision making and enhance the quality of medical care for the population