Two type two diabetes drugs have been found to protect the brain from Alzheimer's disease.
Researchers at Lancaster and Ulster universities found that diabetes drugs liraglutide and lixisenatide not only protected the brain from Alzheimer's, but could also restore memories.
Published in the journal Neuropharmacology, researchers gave daily injections of the drugs to mice for 10 weeks.
Findings showed the levels of amyloid plaque – found in the brains of Alzheimer's patients – were lowered during the trial. Memories were improved and mice were able to better recognise objects, researchers said.
The authors believe liraglutide and lixisenatide could offer a new treatment for Alzheimer's disease. By next year, it is estimated there will be 520,000 people with Alzheimer's in the UK and 850,000 with dementia.
The two drugs work to treat diabetes by increasing insulin production, which reduces the amount of sugar in the blood and helps to slow digestion.
Study leader Christian Holscher said: "These are very exciting results. There are no drugs on the market for Alzheimer's disease that actually treat the disease, all we currently have are two types of drugs that mask the symptoms for a while. Lixisenatide and liraglutide offer a real improvement by treating the basis of the disease and, therefore, preventing degeneration."
The Alzheimer's Society welcomed the research, saying the findings "could bring about a transformation in the treatment" of the disease. The charity is now funding a clinical trial of liraglutide to treat people with early-stage Alzheimer's.
James Pickett, head of research at the charity, said: "It is exciting that drugs used for type 2 diabetes have been found to be promising as potential treatments for Alzheimer's disease, and could tackle the underlying changes in the brain that are causing the disease.
"Current treatments for Alzheimer's only help with the symptoms for a short while and do not stop the disease from progressing. We believe that the concept of drug repurposing, where drugs already licensed for one condition may be beneficial for dementia, has enormous potential and could deliver new treatments faster and cheaper than producing a new drug from scratch.
"By speeding up the research process we hope to deliver a new dementia treatment within five to 10 years."