Navigation Links
Neuron-nourishing cells appear to retaliate in Alzheimer's
Date:5/22/2012

AUGUSTA, Ga. When brain cells start oozing too much of the amyloid protein that is the hallmark of Alzheimer's disease, the astrocytes that normally nourish and protect them deliver a suicide package instead, researchers report.

Amyloid is excreted by all neurons, but rates increase with aging and dramatically accelerate in Alzheimer's. Astrocytes, which deliver blood, oxygen and nutrients to neurons in addition to hauling off some of their garbage, get activated and inflamed by excessive amyloid.

Now researchers have shown another way astrocytes respond is by packaging the lipid ceramide with the protein PAR-4, which independently can do damage but together are a more "deadly duo," said Dr. Erhard Bieberich, biochemist at the Medical College of Georgia at Georgia Health Sciences University.

"If the neuron makes something toxic and dumps it at your door, what would you do?" said Bieberich, corresponding author of the study published in the Journal of Biological Chemistry. "You would probably do something to defend yourself."

The researchers hypothesize that this lipid-coated package ultimately kills them both, which could help explain the brain-cell death and shrinkage that occurs in Alzheimer's. "If the astrocytes die, the neurons die," Bieberich said, noting studies suggest that excess amyloid alone does not kill brain cells. "There must be a secondary process toxifying the amyloid; otherwise the neuron would self-intoxicate before it made a big plaque," he said. "The neuron would die first."

One of many avenues for future pursuit include whether a ceramide antibody could be a viable Alzheimer's treatment. In the researchers' studies of brain cells of humans with Alzheimer's as well as an animal model of the disease, antibodies to ceramide and Par-4 prevented astrocytes' amyloid-induced death.

Ceramide and Par-4 get packaged in lipid-coated vesicles called exosomes; all cells secrete thousands of these vesicles but scientists are only beginning to understand their normal function. When exosomes become deadly, they are called apoxosomes.

Ceramide and Par-4 are typically not in a vesicle, rather in two distinct parts of a cell. Ceramide appears to take the lead in bringing the two together when confronted with amyloid. Bieberich and colleagues at the University of Georgia reported in 2003 that the deadly duo helps eliminate duplicate brain cells that occur early in brain development when their survival could result in a malformed brain. They suspected then that the duo might also have a role in Alzheimer's.

Risk factors for Alzheimer's include aging, family history and genetics, according to the Alzheimer's Association. Increasing evidence suggests that Alzheimer's also shares many of the same risk factors for cardiovascular disease, such as high cholesterol, high blood pressure and inactivity.


'/>"/>
Contact: Toni Baker
tbaker@georgiahealth.edu
706-721-4421
Georgia Health Sciences University
Source:Eurekalert  

Related medicine news :

1. Study: Heart damage after chemo linked to stress in cardiac cells
2. Scientists discover marker to identify, attack breast cancer stem cells
3. All cancer cells are not created equal
4. Drug kills cancer cells by restoring faulty tumor suppressor
5. Rutgers team discovers novel approach to stimulate immune cells
6. Mayo Clinic: Exhaustion renders immune cells less effective in cancer treatment
7. Cancer Cells in Bloodstream Show Great Diversity: Study
8. Scripps Research scientists show how memory B cells stay in class to fight different infections
9. Gut flora affects maturation of B cells in infants
10. Researchers Rejuvenate Blood-Forming Stem Cells in Mice
11. Presence of fetal cells in women lowers risk of breast cancer but raises risk of colon cancer
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Neuron-nourishing cells appear to retaliate in Alzheimer's
(Date:12/7/2016)... ... December 07, 2016 , ... Wavelink, an ... Remote Control through a new partnership with Splashtop Inc. This remote control for ... solutions to help businesses maximize their uptime and productivity. , Wavelink offers powerful ...
(Date:12/7/2016)... GA (PRWEB) , ... December 07, 2016 , ... In ... route to respond to an emergency medical call when he lost control of his ... After being extricated from his vehicle, he was transported to Atlanta Medical Center, where ...
(Date:12/7/2016)... (PRWEB) , ... December 07, 2016 , ... A quote ... an outpouring of comments on social media that offer a rare glimpse into the ... leading ADHD authority and New York Times bestselling author, has described people with ADHD ...
(Date:12/7/2016)... ... December 07, 2016 , ... When it came time to blow out his candles on his ... the Pediatric Heart Transplant team at Joe DiMaggio Children’s Hospital surprised his family ... hospital’s 30th heart transplant recipient. , “He was playing at home, when we got ...
(Date:12/7/2016)... ... December 07, 2016 , ... ... consultation services to residents in the Sacramento/Folsom region, is initiating a charity event ... , The Another Choice Another Chance treatment center in Sacramento works to provide ...
Breaking Medicine News(10 mins):
(Date:12/7/2016)... 7, 2016 Global Cervical Dysplasia Market: ... global cervical dysplasia market analyzes the current and ... an elaborate executive summary, including a market snapshot ... sub-segments. The research is a combination of ... bulk of our research efforts along with information ...
(Date:12/7/2016)... Dec 7, 2016 Research and Markets has ... End User - Global Forecast to 2021" report to their offering. ... , , ... Billion by 2021, growing at a CAGR of 7.3% during the forecast ... growing prevalence of cancer and rapidly increasing geriatric population across the globe ...
(Date:12/7/2016)... , Dec. 7, 2016  Palatin Technologies, ... has closed on a previously disclosed underwritten public ... Canaccord Genuity acted as sole book-running manager, Roth ... Capital Markets acted as co-manager for the offering. ... $15.4 million in net proceeds, allowing us to ...
Breaking Medicine Technology: