New insights on what causes Alzheimer's disease could arise from a recent discovery made by bioengineers from the University of California, San Diego. The finding concerns the infamous amyloid beta peptides (Aβ)fragments of which form plaques thought to play a role in Alzheimer's disease. The bioengineers found that amyloid beta peptides (Aβ) spontaneously trigger calcium waves in purified cultures of astrocyte cells extracted from the cortex region of rat brains and grown in the lab. These calcium waves could be relevant for understanding the origin of Alzheimer's disease. The accumulation of Amyloid beta fragments and sustained disruption of the calcium balance within cells are leading hypotheses for what causes Alzheimer's disease.
The work also adds to researchers' understanding of a class of cells found in the brain called astrocytes, which have become a hot research topic as evidence mounts suggesting that astrocytes in the brain's cortex do more than provide support to neurons.
The UC San Diego bioengineers published the new findings in the January 25, 2010 issue of the journal ASN NEURO. "We didn't generate these waves artificially. Amyloid beta fragments induced the waves spontaneously, and that raises some interesting questions about the pathophysiology of Alzheimer's disease and how astrocytes may be involved," said bioengineering professor Gabriel Silva from the UC San Diego Jacobs School of Engineering and the senior author on the paper.
The calcium waves Silva and his team observed have not been reported in astrocyte networks in healthy brain cortex tissue, but they have been seen in the cortexes of rats with Alzheimer's disease. "The fact that amyloid beta peptidesindependent of any other cell typeare able to induce calcium waves in astrocyte networks is one of the major findings of the paper," said Silva, who is also affiliated with UC San Diego's Department of Ophthalmology, Neurosciences Progra
|Contact: Daniel Kane|
University of California - San Diego