Parkinson's disease is caused by the death of brain cells that produce a vital chemical known as dopamine, which carries messages that tell the body how and when to move. In tests with 31 monkeys, including a control group, scientists inserted copies of a gene to produce GDNF into a region in the front part of the brain called the striatum. They then induced Parkinson-like conditions by introducing a drug to destroy the dopamine-producing cells. Seventeen weeks after that, not only did the GDNF-treated monkeys show improvement in performing tasks, analysis of brain tissue showed the animals' dopamine systems were actually spared by the treatment.
“The simplest question we're asking is, ‘Does any particular combination of proteins prevent or accelerate degeneration of the neurons?'?said Nicholas Muzyczka, Ph.D., an eminent scholar and professor of molecular genetics and microbiology at UF's College of Medicine who participated in the research. “For some time Dr. Mandel has been working on the idea of introducing a vector into brain that would express GDNF. What they've found is that if you get low-level expression, you can prevent cell death in a part of the brain called the substantia nigra. That's been shown before in rodent models, but it's encouraging to see data that it works in higher animals like monkeys.?/p>
Meanwhile, in separate experiments with rats, researchers used gene therapy to completely reverse abnormal movements called dyskinesias in some of the animals, suggesting a new way to combat the flailing movements produced by a widely used drug treatment for Parkinson's disease. Levodopa, considered the gold standard of current treatment, enables the brain to repleni
Source:University Of Florida Health Science Center