New research on mice suggests vitamin D and transporter proteins found at the blood-brain barrier may help prevent amyloid beta peptide buildup in the brain — reducing the risk of Alzheimer’s disease.

Experts say that advancing age is a major risk factor for Alzheimer’s disease (AD) with AD associated with build-up of the peptide amyloid beta in the brain.

New research published in BioMed Central’s open access journal Fluids and Barriers of the CNS shows that removal of amyloid beta from the brain depends on vitamin D and also on an age-related alteration in the production of transporter proteins which move amyloid beta in and out of the brain.

Researchers believe low levels of vitamin D are related to age-related decline in memory and cognition and are also associated with Alzheimer’s disease.

Investigators from Tohoku University, Japan, looked at the mechanism behind this and found that vitamin D injections improved the removal of amyloid beta from the brain of mice.

Professor Tetsuya Terasaki comments, “Vitamin D appears to increase transport of amyloid beta across the blood brain barrier (BBB) by regulating protein expression, via the vitamin D receptor, and also by regulating cell signaling via the MEK pathway. These results lead the way towards new therapeutic targets in the search for prevention of Alzheimer’s disease.”

The transport of amyloid beta across the BBB is known to be facilitated by transporter proteins which move amyloid beta out of the brain, and other proteins which control influx.

Researchers reviewed the transport of amyloid beta from blood to cerebrospinal fluid (CSF), and from CSF to blood, and discovered transport proteins increase with age, thus aiding the removal of amyloid beta from the CSF and brain.

Professor Gerald Silverberg said, “While increased production of transporter proteins at the blood CSF barrier may help amyloid beta removal from the older brain, production of these proteins eventually fails. This failure may be an important event in brain function as we age and for people with Alzheimer’s disease.”

Source: BioMed Central