Sleep disorder traced to assault on brain cells
Editor's note: The research paper described in this story was retracted on July 30, 2014, after the authors were unable to replicate one of their main results.
Narcolepsy occurs when wayward immune forces launch an attack on brain cells responsible for wakefulness, a new study suggests. In a case of mistaken identity, immune cells that target a protein fragment from a microbial invader also on rare occasions ravage neurons that produce a similar protein fragment, or peptide, researchers report.
The victims of this cross fire are neurons that make a peptide called orexin, a neurotransmitter that is crucial for staying awake. The researchers say this could explain the lack of orexin neurons in people with narcolepsy, as shown previously in patient autopsies. A lack of orexin, also called hypocretin, leaves a person with disordered sleep, daytime drowsiness and the