Researchers zero in on Alzheimer's plaque origin

Apr 9, 2008- Researchers have found that a key ingredient for the formation of Alzheimer's plaques is produced by a brain cell activity, according to a study that helps understand the disease's origin.
The ability of brain cells to absorb substances from their surface, a process called endocytosis, is essential to producing amyloid beta, a protein fragment that clusters together to form Alzheimer's plaques, said the study released Wednesday.
The researchers found that by giving a drug that blocks endocytosis to a mouse with Alzheimer's disease, levels of amyloid beta sank by 70 percent, according to the study published in the journal Neuron.
But using the drug to treat Alzheimer's is not an option because brain cells need to be able to take in substances from the surface, said the neuroscientists at Washington University School of Medicine in St. Louis.
"Blocking endocytosis isn't a viable option for treatment because cells throughout the body, including brain cells, need endocytosis for healthy function," said the study's first author, John Cirrito, research instructor in neurology.
"But we are starting to understand the origins of amyloid beta in more detail now, and what we're learning is opening other options we can pursue to seek new treatments for Alzheimer's disease," he said.
The researchers believe the brain cells may be accidentally taking in amyloid precursor protein (APP), which breaks down into amyloid beta.
In that case, they said, a drug that reduces APP intake could help reduce production of amyloid beta.