It may bring hope to those who are ill

Oct 15, 2009 07:54 GMT  ·  By
A PET scan can show patterns in the brain that aid the physician in diagnosing and treating the Parkinson's disease
   A PET scan can show patterns in the brain that aid the physician in diagnosing and treating the Parkinson's disease

In a new set of experiments conducted on monkeys, researchers have managed to determine a new type of gene therapy aimed at curing the Parkinson's disease. The treatment apparently does not result in the involuntary muscle movements that are a direct consequence of other forms of therapy against the ruthless condition. At this point, the new method is being tested on a small number of volunteers, all of which are showing considerable signs of improvement, Nature News reports.

Existing therapies against the disease revolve around administering the chemical levodopa, or L-DOPA, which is the precursor of the neurotransmitter dopamine. In patients suffering from the condition, levels of this transmitter are dangerously low, and healthcare experts hope that, by making the patients take this substance, they will at least be able to halt the evolution of the disease, if not completely reverse it. However, these treatments are plagued by side-effects, experts admit.

While most patients regain the motor functions shortly after they start using L-DOPA, a few years later, they begin to develop severe and debilitating, physical and psychological side-effects. This means that therapies using the neurotransmitter precursor should only be used when absolutely necessary, and not as the standard in treating Parkinson's. In the new therapy, experts injected macaque monkeys with a neurotoxin that caused bodily tremors, unstable posture and severe joint rigidity, the same symptoms associated with an advanced stage of Alzheimer's.

The monkeys were then injected with a cocktail of three genes, which were administered directly into their brains. All of the three genes have been determined to play an influential role in producing dopamine, the team says. In charge of the investigation were scientists from the Institute of Biomedical Imaging, in Orsay, France, a part of the French Atomic Energy Commission. The team leader has been Institute neurosurgeon Stephane Palfi. Two weeks after the treatment began, the monkeys showed significant signs of improvement and no visible side-effects.

In one of the monkeys, which was followed for 3.5 years, no long-duration side-effects were observed. The researchers say that even the jerky, uncontrolled motions disappeared completely, and that none of the behaviors associated with prolonged exposure to L-DOPA oral treatments was found.