In a small pilot study, a team of US researchers has discovered how vitamin D3, a form of vitamin D, and omega 3 fatty acids may help the immune system clear the brain of amyloid plaques, one of the physical hallmarks of Alzheimer’s disease (AD).
Published in the Journal of Alzheimer’s Disease, the new study builds on previous work by the same team, from the University of California – Los Angeles (UCLA).
The brains of people with Alzheimer’s disease have an abundance of two abnormal structures—amyloid plaques and neurofibrillary tangles—that are made of mis-folded proteins. Amyloid plaques are found in the spaces between the brain’s nerve cells. Dr. Alois Alzheimer first described them in 1906. Plaques consist of largely insoluble deposits of an apparently toxic protein peptide, or fragment, called beta-amyloid.
We now know that some people develop plaques in their brain tissue as they age. However, the Alzheimer’s disease brain has many more plaques in particular brain regions. We still don’t know whether amyloid plaques themselves cause AD or whether they are a by-product of the AD process. We do know that genetic mutations can increase production of beta-amyloid and can cause rare, inherited forms of AD.
How Does Vitamin D Help?
The new research suggests that vitamin D3 may work by activating certain genes and cell signaling networks to ramp up the immune system, which then clears away a key component of amyloid plaques called amyloid-beta protein.
“This new study helped clarify the key mechanisms involved, which will help us better understand the usefulness of vitamin D3 and curcumin as possible therapies for Alzheimer’s disease,” study researcher Dr. Milan Fiala, of the David Geffen School of Medicine at UCLA and the Veterans Affairs Greater Los Angeles Healthcare System, said in a statement.
Researchers conducted the study by taking blood samples from people with and without Alzheimer’s disease, and isolating particular immune cells from the blood that are responsible for clearing away the amyloid-beta protein.
The same scientists conducted past research on vitamin D’s role in the fight against Alzheimer’s, also published in the Journal of Alzheimer’s Disease in 2009. In that study, they found that vitamin D3, together with the spice curcumin, work together to encourage the immune system to have its effects against amyloid-beta protein in the brain.
Another study, published in 2010 in the journal Archives of Internal Medicine, showed that people with low vitamin D blood levels have a higher risk of cognitive decline.