Investigating brain plaque attacks

If the brains of people with Alzheimer’s disease were probed like crime scenes, senile plaques and tangles would almost assuredly be bagged for evidence in the slaying of neurons. That’s because wherever cells die, clumps of “misfolded” proteins called amyloid beta are found.

“It causes and makes these toxic plaques that end up killing the nerve cells in the brain,” explains Patricia Leighton, a researcher at the University of Alberta funded by the Alzheimer Society Research Program.

Patricia Leighton

“When you have a few of the smaller proteins clumped together, they could start interacting with some of the neurotransmitter receptors of nerve cells and disrupting signals,” she said. That, in turn, could lead to Alzheimer’s disease.

In addition to studying amyloid beta’s destructive role, Leighton is also investigating the role of amyloid beta precursor protein, or APP, in healthy brains which may serve a protective function.

Leighton has been working with zebrafish, which, like mice, have a central nervous system and an underlying nerve architecture that makes them a good model for studying the disease process.

Her team has been trying to get fish to generate the kinds of senile plaques found in people with Alzheimer’s by inserting the human APP gene into the fish. These fish will then be used to screen different drugs and therapies.

“The next step would be to take a few of those [therapeutic] candidates that work in zebrafish and test them in other models like mice, and then hopefully take some of them to clinical trials,” she said.

“Funding for graduate students is pretty important so they can have a salary while they do graduate work,” she said. “Being able to work in the lab full-time is really good and getting papers published wouldn’t have been possible if I was spending time as a teaching assistant or working another part-time job.”

Although Leighton’s interest in science started in the chemistry lab, she soon took a liking to biology at the University of Alberta. When her grandfather had a stroke, it piqued her interest in neurodegenerative disease. She also spent time volunteering in a nursing home where she would visit with residents who had suffered strokes or had Alzheimer’s disease.

Untangling the mysteries of dementia requires work like Patricia’s. Help the Alzheimer Society of Canada continue to fund this kind of research with a donation to the Alzheimer Society Research Program. Learn more at

Last Updated: 11/08/2017