A group of 12 USF research scientists recently discovered that a signaling protein helps to significantly reverse the effects of Alzheimer’s disease – placing them among the first to discover a potential breakthrough in the disease’s 103-year history.
Alzheimer’s, a progressive degenerative disease, alters the brain and causes impairments to memory, thinking and behavior. The study, which began in 2007 and was published earlier this month, found that a protein called GM-CSF, which has similar functions to hormones and is found in arthritis patients, helps to stimulate and increase the body’s white blood cells, which, in return, attack and remove amyloid plaques found in the brain of Alzheimer’s patients.
“The study comes out of an interest in the fact that there are (some) special humans that do not get Alzheimer’s disease,” said Huntington Potter, who holds the Eric Pfeiffer chair at the USF Health Byrd Alzheimer’s Institute.
It has been assumed for years that people with rheumatoid arthritis – a chronic, autoimmune disorder that mainly affects the joints and the surrounding tissues – have a negative risk of developing the disease, Potter said. His study, which was conducted on mice, proved the theory to be true.
During the study, three types of growth factors, naturally occurring protein that causes cells to grow and divide, were used and analyzed. They include, Granulocyte Colony Stimulating Factor (G-CSF), Macrophage Colony Stimulating Factor (M-CSF) and Granulocyte Macrophage Colony Stimulating Factor (GM-CSF).
“We tested all three growth factors directly in the brain and we found the specific one, which is GM-CSF, which had the greatest effect of removing amyloid deposits in seven days. G-CSF had a small effect, and M-CSF had no effect on the amyloid (deposits) when injected into the brain,” said Tim Boyd, a USF graduate student who proposed the idea for the study.
The publication of the results, called “GM-CSF Upregulated in Rheumatoid Arthritis Reverses Cognitive Impairment and Amyloidosis in Alzheimer Mice,” took a year to complete and was published Aug. 12 in the Journal of Alzheimer’s Disease.
According to Potter, there is a drug currently on the market called Leukine that is in the form of GM-CSF and has been approved by the Food and Drug Administration.
This drug is typically used by cancer patients as well as bone marrow donors to help prevent certain kinds of infections.
“Leukine helps (increase cancer patients’) white blood cells, and helps prevent infections in certain kinds of patients like AML, a type of leukemia, since those patients are susceptible to fungal infections,” Boyd said. “The drug also has no serious side effects.”
Boyd said the team plans to conduct clinical trials investigating the effects of GM-CSF (Leukine) on humans with mild to moderate Alzheimer’s disease in January.
“The Leukine will be tried in Alzheimer’s patients,” Potter said. “If it works, then there will be a drug that is … safe and … effective. Now we have to show that it works on humans.”
Boyd said the drug may be the first to reverse the disease.
“Most of the drugs on the market either slows down or halts the progression of the disease,” Boyd said. “This has a great potential to possibly reverse the disease if it works as the same matter as it does on mice.”
USF Health Byrd Alzheimer’s Institute plans to conduct clinical trials while also learning more about the mechanism of this signaling protein GM-CSF (Leukine) in the laboratory.
Patients will be treated five days a week for three weeks. During that time, they will be analyzed to see if there is a change in their cognitive status. The researchers will follow up with them three months later and then again three months after that to determine whether there was any long-term effect from the drug – positive or negative, Potter said.
“Compared to the other drugs that have come out from the laboratories from around the world, this has, we think, more promise than other approaches,” he said.