Discovery sheds light on Alzheimer's mystery

October 22, 2012 by April Reese Sorrow

(Medical Xpress)—In 1906, when Alois Alzheimer discovered the neurodegenerative disease that would later be named for him, he saw amyloid-beta plaques and neurofibrillary tangles inside the brain. Several decades later, abnormal protein structures called Hirano bodies also were frequently observed in patients with neurodegenerative diseases.

A hundred years and many millions of suffering patients and families later, scientists still don't know what these structures do. They do know, thanks to new research from the University of Georgia, that Hirano bodies may have a protective role in the brain of Alzheimer's patients.

Matthew Furgerson, a doctoral candidate in the UGA Franklin College of Arts and Sciences department of biochemistry and molecular biology, used cell culture models to study the role of Hirano bodies in induced by AICD, or a fragment of AICD called c31, that are released inside the cell during cleavage of the amyloid . This cleavage also produces amyloid-beta, which forms extracellular plaques.

Furgerson found mixtures of amyloid precursor protein, c31 and tau-the protein that forms the intracellular neurofibrillary tangles-or of AICD and tau cause synergistic cell death that is significantly higher than cell death from amyloid precursor protein, c31, AICD or tau alone.

"This synergistic cell death is very exciting," Furgerson said. "Other groups have shown synergy between extracellular amyloid beta or with tau, but these new results show that there may be an important interaction that occurs inside the cells."

The results of this study were published in the September issue of . Ruth Furukawa, associate research scientist, and Marcus Fechheimer, professor of , are co-authors on the paper.

Furgerson also found cell death is significantly reduced in cells that contain Hirano bodies compared to cells without Hirano bodies. The protective effect of Hirano bodies was observed in in both the presence and absence of tau. The findings reveal that Hirano bodies have a protective role during the progression of Alzheimer's disease.

While this research offers no cure for the disease, it does offer some understanding about how the disease operates. The lab has been a leader of Hirano body research for more than a decade due to their development of cell culture and mouse model systems.

Before the mouse model, the only way to study these abnormal structures was in post-mortem brain tissue. The recently developed Hirano body mouse model is currently being used with an Alzheimer's model mouse to investigate whether cell culture results can translate to a complex animal.

"I feel privileged to lead a team that might be able to contribute knowledge to help us understand Alzheimer's disease processes," Fechheimer said. "Other groups have focused on plaques and tangles, and we don't know as much about Hirano bodies. Results from the cell culture studies are exciting and reveal the protective role of Hirano bodies. Our ongoing studies with mouse models are essential to defining the role of Hirano bodies in Alzheimer's disease progression in a whole animal."

Explore further: Researchers develop first mouse model to study important aspect of Alzheimer's

More information: www.ncbi.nlm.nih.gov/pmc/articles/PMC3445605/

Related Stories

Researchers develop first mouse model to study important aspect of Alzheimer's

November 7, 2011
Hirano bodies are almost indescribably tiny objects found in nerve cells of people suffering from conditions such as Alzheimer's, mad cow and Lou Gehrig's diseases. Yet for decades, researchers weren't sure if these structures ...

Case of mistaken identity: Study questions role of A-beta molecules in Alzheimer's disease pathology

June 28, 2011
Increasingly, researchers are suggesting that amyloid plaques and neurofibrillary tangles may be relatively late manifestations in the course of Alzheimer's disease (AD) pathology. Identifying earlier events in the development ...

Road block as a new strategy for the treatment of Alzheimer's

August 22, 2011
Blocking a transport pathway through the brain cells offers new prospects to prevent the development of Alzheimer's. Wim Annaert and colleagues of VIB and K.U. Leuven discovered that two main agents involved in the inception ...

Alzheimer's vaccine cures memory of mice

December 9, 2011
(Medical Xpress) -- A vaccine that slows the progression of Alzheimer's disease and other types of dementia has been developed by researchers at the University of Sydney's Brain and Mind Research Institute (BMRI).

Alzheimer's protein detected in brain fluid of healthy mice

September 21, 2011
(Medical Xpress) -- One of the most promising markers of Alzheimer’s disease, previously thought only to be inside nerve cells, now appears to be normally released from nerve cells throughout life, according to researchers ...

Recommended for you

Newly discovered biomarkers may lead to promising diagnostic tool for Alzheimer's

July 28, 2017
Diagnosing Alzheimer's disease and determining a patient's prognosis is an inexact business, and that stands in the way of better personalized care and advances in treatment.

BACE-Inhibitor successfully tested in Alzheimer's animal model

July 28, 2017
The protein amyloid beta is believed to be the major cause of Alzheimer's disease. Substances that reduce the production of amyloid beta, such as BACE inhibitors, are therefore promising candidates for new drug treatments. ...

Scientists use new data mining strategy to spot those at high Alzheimer's risk

July 28, 2017
The push to develop treatments for Alzheimer's disease has been a promising and disappointing endeavor over the past two decades, yielding a greater understanding of the disease yet still failing to generate successful new ...

Lifestyle changes to stave off Alzheimer's? Hints, no proof

July 20, 2017
There are no proven ways to stave off Alzheimer's, but a new report raises the prospect that avoiding nine key risks starting in childhood just might delay or even prevent about a third of dementia cases around the world.

Blood test identifies key Alzheimer's marker

July 19, 2017
A new study led by researchers at Washington University School of Medicine in St. Louis suggests that measures of amyloid beta in the blood have the potential to help identify people with altered levels of amyloid in their ...

Steering an enzyme's 'scissors' shows potential for stopping Alzheimer's disease

July 19, 2017
The old real estate adage about "location, location, location" might also apply to the biochemical genesis of Alzheimer's disease, according to new research from the University of British Columbia.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.