Researchers are engaged in finding a cure for Alzheimer's disease from the liver of patients.
In Alzheimer's disease, the brain accumulates a molecule called A-beta that can be toxic to its cells, and finding ways to clear A-beta may be a key to its treatment or prevention.
An international team of researchers from University of Washington and University of Hong Kong provide fresh insights into the way A-beta in the peripheral blood stream affects A-beta clearance in the brain.
They have found that when circulating A-beta levels in the blood stream of rats were elevated, known amounts of radioactively tagged A-beta were swept from the brain more slowly.
The study showed that freely circulating A-beta concentrations outside the brain could regulate A-beta clearance rates inside the central nervous system.
The brain does not act alone in the task of clearing A-beta. It can be shuttled back and forth between compartments inside the brain and the peripheral blood supply where A-beta interacts with other organ systems.
Previous studies have shown that the liver plays an important role in removing A-beta from the blood.
"So, we thought if we temporarily prevented liver-mediated clearance it might be possible to set or 'clamp' peripheral A-beta levels long enough to find out whether A-beta in the blood stream affects A-beta clearance from the brain," said Dr. David Cook of the Puget Sound Veterans' Affairs Health Care System and University of Washington School of Medicine.
"We were a bit surprised to see how effective this strategy was. Peripheral A-beta clearance immediately halted almost completely.
"For several years it has been suggested that the circulatory system can act like an A-beta sink. The data clearly show that the liver is the primary drain," he added.
"The liver influences virtually everything that happens in the body, so it is not far-fetched to imagine that in the future it may be possible to find ways to help the brains of Alzheimer's disease patients with their livers," said Hepatology expert, Dr. Sum Lee of the University of Hong Kong.
The study has been published in the Journal of Alzheimer's Disease.