Print

Print


An Embryonic Stem Cell Model For Parkinson's Disease

October 5, 2004

Despite the well-characterized cellular basis of Parkinson's disease -- the
degeneration of dopamine-production neurons -- the molecular mechanisms
responsible for the neurodegeneration remain unknown. Part of the challenge is
finding a model that can adequately mimic the loss of dopamine cells. In two papers
published in PLoS Biology, Asa Abeliovich and colleagues make the case that a
model based on mouse embryonic stem cells offers a promising platform for
dissecting the disease mechanism of Parkinson's.

Working with these cells, the researchers created dopamine neurons deficient in
DJ-1, a gene mutated in an inherited form of Parkinson's. They report that DJ-1-
deficient cells -- and especially DJ-1-deficient dopamine neurons -- display
heightened sensitivity to oxidative stress, caused by products of oxygen metabolism
that react with and damage cellular components like proteins and DNA. In a second
paper, they link DJ-1 dysfunction to the aggregation of alpha-synuclein, a hallmark
of Parkinson's neuropathology.

Oxidative stress has long been associated with neuronal cell death and
neurodegenerative diseases like Parkinson's. Proving a causal relationship
between oxidative stress and neurodegeneration, however, requires establishing a
molecular mechanism. These results support a link between oxidative damage and
disease, and provide a tractable model for both studying the molecular mechanisms
of neurodegenerative disease and screening potential neuroprotectant drugs. The
authors are hoping to extend their work to human embryonic stem cells, but their
work is limited by the availability of such cells under the current NIH guidelines.

###

Citations:

1) Martinat C, et al. (2004) Sensitivity to Oxidative Stress in DJ-1-Deficient
Dopamine Neurons: An ES-Derived Cell Model of Primary Parkinsonism. PLoS Biol
2 (11): e327.

2) Shendelman S, et al. (2004) DJ-1 Is a Redox-Dependent Molecular Chaperone
that Inhibits a-Synuclein Aggregate Formation. PLoS Biol 2 (11): e362.

SOURCE: Science Daily Mind & Brain News, Oct 5, 2004
http://tinyurl.com/4o5ah

Reference:

Search Science Daily for Parkinson
http://tinyurl.com/646sg

* * *

----------------------------------------------------------------------
To sign-off Parkinsn send a message to: mailto:[log in to unmask]
In the body of the message put: signoff parkinsn