A newly identified protein, conserved dopamine neurotrophic factor (CDNF), protects and even rescues damaged dopamine-producing neurons in a rat experimental model of Parkinson disease, according to Finnish researchers (Lindholm P et al. Nature. 2007;448:73-77).
In this model, a neurotoxin that targets dopamine neurons is injected into the striatum on one side of the animal's brain, which results in a circling behavior reflecting an imbalance of dopamine activity in the brain's hemispheres. Pretreatment with CDNF 6 hours before the toxin injection significantly reduced circling and almost completely rescued the dopamine neurons; CDNF given 4 weeks after toxin administration actually helped restore dopamine neurons and also significantly reduced circling behavior.
Stephenson J. Preventing Neurodegeneration. JAMA. 2007;298(7):731. doi:10.1001/jama.298.7.731-a