 |
 |
The source of this article is NewsTarget.com: http://tinyurl.com/4vd5x Friday, February 04, 2005 Monkey embryonic stem cells reverse Parkinson's Disease Researchers at Kyoto University have shown that neurons can be generated by monkey embryonic stem cells and transplanted into the brains of monkeys suffering from Parkinson disease. The same researchers previously showed that mouse stem cells can differentiate into neurons under certain specific conditions. The discovery may have an impact in the controversial area of human embryonic stem cell research. The replenishment of missing neurons in the brain as a treatment for Parkinson disease reached the stage of human trials over 15 years ago, however the field is still in its infancy. Researchers from Kyoto University have now shown that dopamine-producing neurons (DA neurons) generated from monkey embryonic stem cells and transplanted into areas of the brain where these neurons have degenerated in a monkey model of Parkinson disease, can reverse parkinsonism. Studies of animal models of Parkinson disease as well as clinical investigations, have shown that transplantation of fetal DA neurons can relieve the symptoms this disease. These same culture conditions, technically simple and efficient, were recently applied to primate embryonic stem cells and resulted in the generation of large numbers of DA neurons. In their current JCI study, Jun Takahashi and colleagues generated neurons from monkey embryonic stem cells and exposed these cells to FGF20, a growth factor that is produced exclusively in the area of the brain affected by Parkinson disease and is reported to have a protective effect on DA neurons. In an accompanying commentary, J. William Langston from the Parkinson's Institute, California, describes this study as a milestone in the development of stem cell technology but cautions that while the observations are encouraging, the reported number of surviving DA neurons was very low, only 1--3% of the cells surviving, well below the estimated number of DA neurons that survive after fetal cell transplants (approximately 10%). While this may be a difference observed between transplantation in monkeys and humans, Langston stresses that it may be necessary for far more DA neurons to survive and for that survival to be long lasting in order to render this approach as a useful therapy in humans. Source: http://www.sciencedaily.com/releases/2005/01/050111124158.htm ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn