Study in ageing cats offers clues to Alzheimer’s

A new UK study has found that ageing cat brains show similar hallmarks of Alzheimer’s disease in humans. 

As cats grow older, they can develop feline dementia, which appears as behavioural changes such as yowling more at night, disrupted sleep patterns and signs of confusion or disorientation. Earlier research showed that, as in humans with Alzheimer’s disease, the toxic protein amyloid-beta also accumulates in the brains of aged cats. However, it was unclear how far this affected brain function. 

Researchers at the University of Edinburgh examined postmortem brains of seven young cats and 18 older ones, including eight with feline dementia. They found that the older cats, with or without dementia, had more amyloid-beta in the brain. This toxic protein plaques also accumulated at synapses — the connections that allow nerve cells to communicate.  

In all the older cats, two types of brain support cells clustered around amyloid-beta plaques and corroded the damaged synapses. In humans with Alzheimer’s, loss of synapses strongly predicts reduced memory and thinking ability.  

“Our findings highlight the striking similarities between feline dementia and Alzheimer’s disease in people. This opens the door to exploring whether promising new treatments for human Alzheimer’s disease could also help our ageing pets,” said Robert McGeachan, veterinarian at the University of Edinburgh and first author of the study published in the European Journal of Neuroscience.