Antidepressants can be used to treat Alzheimer’s disease

Scientists at the University of Waterloo have discovered that antidepressant medications can be used to treat Alzheimer’s disease.

The study, recently published in ACS Chemical Neuroscience, found that selective serotonin uptake inhibitors (SSRI medication) can delay the development and growth of amyloid-beta proteins, which can clump together and form a plaque, contributing to disease symptoms.

“These are promising findings for people with Alzheimer’s who are on SSRIs,” said Praveen Nekkar, a professor at the School of Pharmacy at Waterloo. “These finding may not only highlight benefits for people with depression and Alzheimer’s but can also provide insights to serve as a guide to future drug development to treat the disease.”

There are currently over 500,000 Canadians living with dementia, and no drugs on the market that offer a cure. Typically, developing any new drug, including the required clinical trials and regulatory approval, can take decades and costs billions of dollars.

Alzheimer’s disease is a progressive condition that worsens over time. It can occur when amyloid-beta proteins in the brain clump together and form plaques. These plaques block cell-to-cell signals, resulting in delayed cognitive function. As these plaques grow, the brain’s ability to make connections and send and receive information becomes further impaired.

Approximately 50 per cent of people who are diagnosed with Alzheimer's also have depression.

Nekkar and his team, who study Alzheimer's and explore novel applications of drugs that have already been approved by regulatory agencies, tested the drug’s effect on amyloid-beta in the lab, experimenting with the type and amount of SSRIs.

Though further testing is required, the researchers believe the knowledge can one day inform how healthcare providers approach treatment in patients with both depression and Alzheimer's, perhaps leading to the use of SSRIs as an early intervention for people who have a family history of dementia.

“Our results can also inform future drug development,” said Nekkar. "The chemical structure of SSRIs presents a type of blueprint for how to develop a medication that will prevent amyloid beta aggregation.

“We can explore developing new drugs based on that model to treat Alzheimer’s.”