Navigation Links
Why do neurons die in Parkinson's disease?
Date:11/10/2011

Boston, Mass. - Current thinking about Parkinson's disease is that it's a disorder of mitochondria, the energy-producing organelles inside cells, causing neurons in the brain's substantia nigra to die or become impaired. A study from Children's Hospital Boston now shows that genetic mutations causing a hereditary form of Parkinson's disease cause mitochondria to run amok inside the cell, leaving the cell without a brake to stop them. Findings appear in the November 11 issue of Cell.

Mitochondrial movement is often a good thing, especially in neurons, which need to get mitochondria to cells' periphery in order to fuel the axons and dendrites that send and receive signals. However, arresting this movement is equally important, says senior investigator Thomas Schwarz, PhD, of Children's F.M. Kirby Neurobiology Center, since it allows mitochondria to be quarantined and destroyed when they go bad.

"Mitochondria, when damaged, produce reactive oxygen species that are highly destructive, and can fuse with healthy mitochondria and contaminate them, too," Schwarz says. "It's the equivalent of an environmental disaster in the cell."

Studying neurons from fruit flies, rats and mice, as well as cultured human cells, Schwarz and colleagues provide the most detailed understanding to date of the effects of the gene mutations, which encode the proteins Parkin and PINK1. They demonstrate how these proteins interact with proteins responsible for mitochondrial movement -- in particular Miro, which literally hitches a molecular motor onto the organelle.

Normally, when mitochondria go bad, PINK1 tags Miro to be destroyed by Parkin and enzymes in the cell, the researchers showed. When Miro is destroyed, the motor detaches from the mitochondrion. The organelle, unable to move, can then be disposed of: The cell literally digests it.

But when either PINK1 or Parkin is mutated, this containment system fails, leaving the damaged mitochondria free to move about the cell, spewing toxic compounds and fusing to otherwise healthy mitochondria and introducing damaged components.

The study's findings are consistent with observed changes in mitochondrial distribution, transport and dynamics in other neurodegenerative diseases such as Huntington's disease, Alzheimer's disease, amyotrophic lateral sclerosis (Lou Gehrig's disease), and Charcot-Marie-Tooth disease, the researchers note.

Although the team studied a rare hereditary form of Parkinson's, the findings may shed light on what's going on in the more common sporadic form of the disease, Schwarz says.

"Whether it's clearing out damaged mitochondria, or preventing mitochondrial damage, the common thread is that there's too much damage in mitochondria in a particular brain region," he says.

While Schwarz sees potential in gene therapy to restore normal PINK1 or Parkin to neurons, he is more interested in the possibility of helping neurons flush out bad mitochondria or make enough new, healthy mitochondria to keep them viable. "We may need to do both," he says.


'/>"/>

Contact: Erin Tornatore
erin.tornatore@childrens.harvard.edu
617-919-3110
Children's Hospital Boston
Source:Eurekalert

Related medicine news :

1. Advanced technology reveals activity of single neurons during seizures
2. Can you hear me now? Researchers detail how neurons decide how to transmit information
3. Bilingual neurons may reveal the secrets of brain disease
4. Human stem cells transformed into key neurons lost in Alzheimers
5. Learning causes structural changes in affected neurons
6. Neurons work like a chain of dominos to control action sequences
7. Neurons cast votes to guide decision-making
8. Neuralstem stem cells survive and differentiate into neurons in rats with stroke
9. With magnetic nanoparticles, scientists remotely control neurons and animal behavior
10. Blinking neurons give thoughts away
11. Could HPV Raise Womens Risk for Heart Disease?
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:10/13/2017)... ... October 13, 2017 , ... PurhealthRX , a leading Health ... technology. Applying the Purzorb™process to full spectrum CBD oil will revolutionize the rapidly growing ... form that can be easily incorporated into liquid products, while reducing costs to end ...
(Date:10/13/2017)... ... , ... The Visiting Nurse Association (VNA) of Somerset Hills is proud to ... unique items from across the nation, this holiday-themed event will raise funds and awareness ... VNA. The boutique will be open Saturday, November 4 (10:00 a.m. – 5:00 ...
(Date:10/13/2017)... ... October 13, 2017 , ... Coveros, a leader ... been awarded a contract by the Center for Medicare and Medicaid Services (CMS). ... the enterprise use of Agile methodologies in a consistent and high value manner ...
(Date:10/12/2017)... , ... October 12, 2017 , ... Planet Fitness, one ... U.S., announced today its plans to open a flagship location in Covington, LA at ... former Rooms To Go store next to Office Depot in the Holiday Square shopping ...
(Date:10/12/2017)... ... October 12, 2017 , ... Information about the technology: ... develop to enable prevention of a major side effect of chemotherapy in children. ... pediatric patients. For cisplatin, hearing loss is FDA listed on-label as a dose ...
Breaking Medicine News(10 mins):
(Date:10/11/2017)... -- Caris Life Sciences ® , a leading innovator in ... medicine, today announced that St. Jude Medical Center,s Crosson ... as its 17 th member. Through participation with ... Institute will help develop standards of care and best ... cancer treatment more precise and effective. ...
(Date:10/7/2017)... --  Provista, a proven leader in the supply ... power, today announced a new resource area on Provistaco.com ... is the online home for case studies, articles on ... releases, slideshows and events. ... at their fingertips, viewers can also watch short videos ...
(Date:10/2/2017)... Diplomat Pharmacy, Inc. (NYSE: DPLO ... LLC , and named its founder as Diplomat,s chief ... Tennessee , will operate under Diplomat subsidiary ... offerings for health care partners to include IT outsourcing, ... "In an interoperable world, technology delivers comprehensive insight ...
Breaking Medicine Technology: