Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Studies demonstrate link among Alzheimer's disease, Down syndrome and atherosclerosis

Studies implicate damage inflicted by amyloid protein as shared disease mechanism

Nearly 20 years ago Huntington Potter kicked up a storm of controversy with the idea that Down syndrome and Alzheimer’s were the same disease. Now the evidence is in: He was right.

And that’s not all. Down syndrome, artery-clogging cardiovascular disease, and possibly even diabetes, appear to share a common disease mechanism with Alzheimer’s disease, Dr. Potter and colleagues at the Florida Alzheimer’s Disease Research Center, USF Health Byrd Alzheimer’s Institute, recently reported.

The researchers’ two papers – one in Molecular Biology of the Cell and the other in PLoS ONE -- implicate the Alzheimer’s-associated protein beta amyloid (amyloid protein), which damages the microtubule transport system responsible for moving chromosomes, proteins and other cargo around inside cells. Both studies were done in mice and humans cell cultures modeling Alzheimer’s disease. Together, the laboratory discoveries suggest that protecting the microtubule network from this amyloid damage might be an effective way to prevent or even reverse Alzheimer’s disease and associated disorders.

The first paper, by Antoneta Granic and colleagues published online Dec. 23 in Molecular Biology of the Cell, provides the mechanism behind previous work by Dr. Potter’s laboratory showing that all Alzheimer’s disease patients harbor some cells with three copies of chromosome 21, known as trisomy 21, instead of the usual two. Trisomy 21 is a characteristic shared by all the cells in people with the birth defect Down syndrome. This earlier work demonstrated that Alzheimer’s disease could be considered a late onset form of Down syndrome.

By age 30 to 40, all people with Down syndrome develop the same brain pathology seen in Alzheimer’s disease, including a nerve-killing buildup of sticky amyloid protein clumps. This contributes to accelerated nerve cell loss and dementia.

With the study reported in MBC, Dr. Potter and his colleagues now show that the Alzheimer’s-associated amyloid protein is the culprit that interferes with the microtubule transport system inside cells. The microtubules are responsible for segregating newly duplicated chromosomes as cells divide. “Beta amyloid basically creates potholes in the protein highways that move cargo, including chromosomes, around inside cells,” said Dr. Potter, who holds the Eric Pfeiffer Endowed Chair for Research on Alzheimer’s Disease.

When the microtubule network is disrupted, chromosomes can be incorrectly transported as cells divide and the result is new cells with the wrong number of chromosomes and an abnormal assortment of genes. For example, Down syndrome cells contain three copies of the beta amyloid gene on chromosome 21 – leading to more accumulation of the “bad” amyloid protein over a lifetime, Dr. Potter says. “Alzheimer’s disease probably is caused in part from the continuous development of new trisomy 21 nerve cells, which amplify the disease process by producing extra beta amyloid.”

The second paper by lead author Jose Abisambra and colleagues, published Dec. 31 in the online journal PLoS ONE, describes another consequence of the damaged microtubule network caused by the amyloid protein.

Many Alzheimer’s disease patients also commonly develop vascular diseases and diabetes. Whether this coincidence is bad luck or due to shared disease processes is intensely debated. Research teams have investigated the role that low-density lipoprotein (LDL), the bad cholesterol that causes atherosclerosis, cardiovascular disease and stroke, may play in the development of Alzheimer’s with mixed results. However, the USF group focused on the amyloid protein’s potential effects on LDL metabolism. The receptor needed to detect and use LDL is among the proteins transported by the microtubules.

As previously reported by their colleagues in the MBC paper, the second USF team found that the amyloid protein inflicts damage to the microtubule network. As a consequence, the receptor needed to pull LDL circulating throughout the bloodstream into the body’s cells has trouble getting to the cell surface to retrieve this bad cholesterol. This interference with LDL metabolism may allow bad cholesterol to build up in into plaques that choke off blood supply to the brain and heart in people with Alzheimer’s, Dr. Potter said.

Similarly, other key proteins – including insulin receptors and receptors for brain signaling molecules -- are also likely locked inside cells when the transport system is damaged by amyloid or other factors. “The insulin receptors are needed to get blood sugar inside the cell where it can be used for energy. The nerve cell signaling receptors help promote memory and learning,” Dr. Potter said. “So, if these receptors are unable to function properly, it may lead to diabetes and problems with learning and memory.”

“We’re beginning to understand how conditions like cardiovascular disease and diabetes may manifest some of the same underlying disease processes as Alzheimer’s disease,” he said, “rather than being independent diseases that just happen to develop in the same patient.”

The studies were supported by funds from the USF Health Byrd Alzheimer’s Institute, the Eric Pfeiffer Chair for Research on Alzheimer’s Disease, and the National Institute on Aging, sponsor of the statewide Florida Alzheimer’s Disease Research Center at the University of South Florida.

Journal articles cited:

1. “Alzheimer Ab Peptide Induces Chromosome Mis-segregation and Aneuploidy, including Trisomy 21; Requirement for Tau and APP,” Antoneta Granic, Jaya Padmanabhan, Michelle Norden, and Huntington Potter. Molecular Biology of the Cell, Dec. 23, 2009.

2. “LDLR Expression and Localization Are Altered in Mouse and Human Cell Culture Models of Alzheimer’s Disease,” Jose Abisambra, Tina Fiorella, Jaya Padmanabhan, Peter Neame, Inge Wefes, and Huntington Potter, PLoS ONE, Volume 5, Issue 1. (January 2010).

- USF Health –
USF Health ( is dedicated to creating a model of health care based on understanding the full spectrum of health. It includes the University of South Florida’s colleges of medicine, nursing, and public health; the schools of biomedical sciences as well as physical therapy & rehabilitation sciences; and the USF Physicians Group. With more than $380.4 million in research grants and contracts last year, the University of South Florida is one of the nation’s top 63 public research universities and one of only 25 public research universities nationwide with very high research activity that is designated as community-engaged by the Carnegie Foundation for the Advancement of Teaching.

Anne DeLotto Baier | EurekAlert!
Further information:

More articles from Studies and Analyses:

nachricht Diagnoses: When Are Several Opinions Better Than One?
19.07.2016 | Max-Planck-Institut für Bildungsforschung

nachricht High in calories and low in nutrients when adolescents share pictures of food online
07.04.2016 | University of Gothenburg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>