• Researchers at Johns Hopkins University have identified more than 200 types of misfolded proteins in rats that could be associated with Alzheimer’s.

• For decades, the research on Alzheimer’s was dominated by a battle between A-beta and tau amyloids, both of which can kill neurons and impact the brain's ability to function. 

• A new study suggests, however, that these sticky brain plaques may not be operating alone.

• The findings could lead the way to finding new therapeutic targets and treatments in humans that could provide relief for millions of people who suffer from Alzheimer’s and dementia.

• The results were published in Science Advances.

How was the study conducted?

• To understand the molecular differences between older brains that are mentally sharp and those that are experiencing decline, a team of researchers studied 17 two-year-old rats that grew up in the same colony. 

• Seven rats performed poorly on memory and problem-solving tests and were considered cognitively impaired, while 10 performed as well as 6-month-old rats.

• The researchers then measured more than 2,500 types of protein in the hippocampus, the part of the brain associated with spatial learning and memory. 

• For the first time, scientists were able to determine for a large number of proteins whether individual proteins were misshapen or folded incorrectly, allowing the researchers to work out which proteins misfold for all the rats and are associated with aging in general versus which proteins specifically misfold in cognitively impaired rats.

• More than 200 proteins were misfolded in the cognitively impaired rats yet maintained their shapes in the cognitively healthy rats. 

• The findings suggest that some of those proteins are contributing to cognitive decline.

• Misfolded proteins are unable to carry out tasks necessary for a cell to function properly, so cells have a natural surveillance system that identifies and destroys these misbehaving proteins. 

• Previously, researchers thought misfolded proteins — specifically A-beta and tau proteins — were only disruptive when they clumped into amyloids.

• Next, the team plans to look at misfolded proteins under high-resolution microscopes to get a more detailed picture of what their deformities look like at the molecular level.

What is Alzheimer’s disease?

• More than 57 million people have dementia worldwide.

• Alzheimer’s disease is the most common form of dementia and may contribute to 60-70% of cases.

• It is a progressive disease beginning with mild memory loss and possibly leading to loss of the ability to carry on a conversation and respond to the environment.

• Alzheimer’s disease involves parts of the brain that control thought, memory, and language.

• It can seriously affect a person’s ability to carry out daily activities.

(The author is a trainer for Civil Services aspirants.)