Primate embryonic stem cells as a source of dopaminergic neurons: A novel transplantation for Parkinson's disease.
Extract: The most common neurodegenerative movement disorder in man is Parkinson's disease (PD) and it is characterized by the loss of midbrain dopaminergic neurons in the substantia nigra of the brain. The loss of these neurons, which normally project to the striatum, also causes a decrease in striatal dopamine levels. While being the precursor to dopamine synthesis, L-dihydroxyphenylalanine (L-DOPA) can initially improve the symptoms of the disease, such as resting tremor and a poverty of movement, its effectiveness diminishes with time. Deep brain stimulation and fetal dopaminergic neuron transplantation are two available treatments for the motor complications that subsequently develop. Transplantation of fetal dopaminergic neurons has been shown to be effective at producing symptomatic relief in both animal models and patients of PD. This therapy is limited, however, due to both the technical and ethical difficulties in obtaining sufficient and appropriate donor fetal brain tissue. Embryonic stem (ES) cells are self-renewing, pluripotent cells derived from the inner cell mass of the preimplantation blastocyst. These cells have both proliferative and differentiation capacities, thus fulfilling many of the characteristics required of a cell source for cell-replacement therapy. Stromal cell-derived inducing activity (SDIA) (an activity to induce neural differentiation of ES cells by a soluble factor or a cell surface-anchored molecule) is present on the surface of stromal (connective tissue) cells.
Takagi
Yasushi
Y
Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Takahashi
Jun
J