Navigation Links
Dementia induced and blocked in Parkinson's fly model
Date:7/31/2009

St. Louis, July 31, 2009 Parkinson's disease is well-known for impairing movement and causing tremors, but many patients also develop other serious problems, including sleep disturbances and significant losses in cognitive function known as dementia.

Now researchers at Washington University School of Medicine in St. Louis have modeled Parkinson's-associated dementia for the first time. Scientists showed that a single night of sleep loss in genetically altered fruit flies caused long-lasting disruptions in the flies' cognitive abilities comparable to aspects of Parkinson's-associated dementia. They then blocked this effect by feeding the flies large doses of the spice curcumin.

"Clinical trials of curcumin to reduce risk of Parkinson's disease are a future possibility, but for now we are using the flies to learn how curcumin works," says author James Galvin, M.D., a Washington University associate professor of neurology who treats patients at Barnes-Jewish Hospital. "This should help us find other compounds that can mimic curcumin's protective effects but are more specific."

Galvin and senior author Paul Shaw, Ph.D., assistant professor of neurobiology, publish their results in the journal Sleep on Aug. 1.

Galvin is an expert in cognitive impairments in human Parkinson's disease; Shaw studies sleep and the brain in fruit flies. The researchers decided collaborate based in part on evidence that increased sleep loss in Parkinson's patients can precede or coincide with increased severity in other Parkinsonian symptoms.

More than 74 percent of Parkinson's patients have trouble sleeping, and up to 80 percent of patients 65 and older who have Parkinson's disease for seven years will develop dementia, according to Galvin.

Shaw's lab has linked sleep loss to changes in the dopaminergic system of the brain, the part of the brain that produces the neurotransmitter dopamine and is at the center of the damage caused by Parkinson's.

"In healthy flies, sleep deprivation decreases dopamine receptor production and causes temporary learning impairments that are fully restored after a two-hour nap," Shaw says.

Shaw and Galvin studied fruit flies genetically modified to make a human protein called alpha-synuclein in their brains. Scientists don't yet know what alpha-synuclein does, nor have they found a fly counterpart for it. But they have shown that it aggregates in the brains of Parkinson's disease patients and believe the processes that cause the aggregations are harming dopamine-producing cells.

Prior studies of fruit flies with human alpha-synuclein in their brains showed that the flies, like human Parkinson's patients, also lose dopamine-producing neurons, have movement-related problems and develop alpha-synuclein aggregations. But scientists had yet to evaluate the flies for signs of dementia.

Lead author Laurent Seugnet, Ph.D., research associate at L'Ecole Suprieure de Physique Chimie Industrielles in France, first tested the flies' learning ability using a procedure he helped develop in Shaw's lab. For the test, Seugnet placed flies in a vial with two branches: one lighted branch containing quinine, a bitter-tasting substance flies prefer to avoid; and a darkened but quinine-free branch. After a few trials, normal flies learn to suppress their natural attraction to the light and fly into the darkened vial instead to avoid the quinine.

Flies with alpha-synuclein in their brains could still learn when they were middle-aged, or about 16 to 20 days old. But when Seugnet deprived them of sleep for 12 hours, he found that their ability to remember was more severely impaired than that of young healthy flies that had also been sleep-deprived.

"This was still true even 10 days later, so it seemed to be a lasting effect," says Seugnet.

Galvin had earlier found that curcumin, a derivative of the spice turmeric, blocks alpha-synuclein aggregation in cell models of Parkinson's disease. Based on this, Seugnet fed curcumin to a new batch of flies, repeated the tests and found middle-aged flies with alpha-synuclein retained their ability to learn as well as normal young flies.

"Thanks to this model our labs have created, Dr. Galvin and I can not only quickly test potential new treatments for these symptoms of Parkinson's, we can also move up our treatments in terms of the timeline along which the disorder develops," says Shaw. "That may give us a real chance to change the course of the disease."


'/>"/>

Contact: Michael C. Purdy
purdym@wustl.edu
314-286-0122
Washington University School of Medicine
Source:Eurekalert

Related medicine news :

1. Older Diabetics Should Avoid Dementia Meds
2. Dakim BrainFitness Now Used in 286 Senior Living Communities, Adding 136 Sites in 12 Months for Dementia-Fighting System
3. New Cases of Alzheimers and Dementia Continue to Rise, Even in the Oldest Old
4. New cases of Alzheimers and dementia continue to rise, even in the oldest old
5. Mayo Clinic study using structural MRI may help accurately diagnose dementia patients
6. Mayo Clinic Study Using Structural MRI May Help Accurately Diagnose Dementia Patients
7. Alzheimers Foundation of America and Samarion(SM) Form Strategic Alliance to Enhance Care for Individuals with Dementia
8. Most neuropsychological tests dont tell Alzheimers disease from vascular dementia
9. LoJack SafetyNet and Project Lifesaver Help Rescue Clients Afflicted With Alzheimers/Dementia Who Wandered
10. Living Alone Increases Odds of Developing Dementia
11. Two New Dakim-Sponsored Blogs Help Families Affected by Dementia
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:10/12/2017)... ... 12, 2017 , ... Asante, a nationally recognized health system ... their existing home health joint venture through an agreement, effective October 1, 2017, ... venture home health company with Asante, delivering clinically integrated care, for the past ...
(Date:10/12/2017)... ... October 12, 2017 , ... Dr. Parsa Mohebi, ... a medical article to the newly revamped Cosmetic Town journal section, ... hair transplant procedure known as Follicular Unit Extraction (FUE). , Dr. ...
(Date:10/12/2017)... ... 2017 , ... Leading pediatric oncology experts at Children’s National Health System ... Congress of the International Society of Paediatric Oncology (SIOP) Oct. 12-15. Chaired by ... and Blood Disorders at Children’s National, and Stephen P. Hunger, M.D., Chief of ...
(Date:10/12/2017)... RAPIDS, Mich. (PRWEB) , ... October 12, 2017 ... ... Wellness, has been named one of Michigan’s 2017 Best and Brightest in Wellness® ... and Brightest in Wellness® awards program on Friday, Oct. 20 from 7:30 a.m. ...
(Date:10/12/2017)... ... October 12, 2017 , ... In the ... a year. In some states—like New York, New Jersey, Massachusetts, Texas, Virginia, Connecticut, ... retirement havens have extremely low property-tax rates, which contributes to the relatively lower ...
Breaking Medicine News(10 mins):
(Date:9/23/2017)... HORSHAM, Pa. , Sept. 22, 2017 ... received a complete response letter from the U.S. Food ... (BLA) seeking approval of sirukumab for the treatment of ... response letter indicates additional clinical data are needed to ... of moderately to severely active RA. ...
(Date:9/22/2017)... -- AVACEN Medical (AVACEN) announced that its CE-Marked AVACEN ... with the widespread pain associated with fibromyalgia in the ... Essex, England commented, "I had difficulty ... sleep at all, tremendous pain, with every movement sending ... AVACEN 100] enough, how this has and is helping ...
(Date:9/19/2017)... , Sept. 19, 2017   ZirMed Inc ., ... analytics, today announced that it has been ranked #1 by ... Black Book™ Rankings 2017 User Survey. ZirMed was recognized ... for large hospitals and medical centers over 200 beds and ... Book,s healthcare technology user survey history. ...
Breaking Medicine Technology: