Protein linked to arthritis could help treat Alzheimer's

A PROTEIN found in patients with arthritis could be used to reverse the mental decline suffered by people with Alzheimer's, new research suggests.

The scientists found that people with rheumatoid arthritis may be protected against dementia because of their condition.

The findings could lead to new treatments for Alzheimer's, which may arrive quicker than usual because a drug already exists to mimic a special protein found in the arthritis patients.

Health campaigners yesterday welcomed the findings in the Journal of Alzheimer's Disease and called for trials to be carried out as soon as possible.

About 71,000 people in Scotland have dementia, which is predicted to rise to 127,000 by 2031, according to Alzheimer Scotland.

The researchers from the University of South Florida looked at the effects of a protein known as GM-CSF in mice bred with Alzheimer's symptoms.

They found that the protein, which is released in patients with rheumatoid arthritis, was able to "completely reverse" cognitive impairment in the mice.

GM-CSF was effective at removing another protein in the Alzheimer's mice - amyloid - which is a major treatment target for dementia. The researchers suggested that GM-CSF stimulated cells in the body that break down the amyloid.

They gave the GM-CSF protein to a group of mice genetically altered to mimic Alzheimer's and a second group of normal aged mice. The two groups were split again, one receiving the GM-CSF treatment and the other a placebo.

The 20-day study revealed that the Alzheimer's mice treated with GM-CSF performed better on memory and learning tests, with the results showing that their memories were similar to normal mice and far improved from their initial ability.

The placebo group of Alzheimer's mice continued to perform at a poor level. Lead author Tim Boyd said: "We were pretty amazed that the treatment completely reversed cognitive impairment in 20 days."

It was previously thought that people with rheumatoid arthritis were less likely to get Alzheimer's because they used non-steroidal anti-inflammatory drugs (NSAIDs) which it was thought could prevent the disease. But recent clinical trials using the drugs for this purpose proved unsuccessful.

Huntington Potter, principal investigator at the university, said: "Our findings provide a compelling explanation for why rheumatoid arthritis is a negative risk factor for Alzheimer's disease."

The expert said a drug form of GM-CSF - known as Leukine - already existed and had been used for many years to treat some cancer patients who needed to generate more immune cells.

"Our study, along with the drug's track record for safety, suggests Leukine should be tested in humans as a potential treatment for Alzheimer's disease," Prof Potter said.

The university is now planning a clinical trial of Leukine in people with mild to moderate Alzheimer's later this year.

The Alzheimer's Research Trust welcomed the study and the move toward actual testing of the drug in patients,

Dr Simon Ridley, the charity's head of research, said: "Positive results in mice can be an important first step for any new treatment, and it's encouraging the team is already planning the crucial next stage of a trial in people."