Emerging restorative treatments for Parkinson's disease: manipulation and inducement of dopaminergic neurons from adult stem cells.

Parkinson's disease (PD) is a common neurodegenerative disease, characterized by a selective loss of midbrain Dopaminergic (DA) neurons. To address this problem, various types of stem cells that have potential to differentiate into DA neurons are being investigated as cellular therapies for PD, including cells derived from embryonic or adult donor tissue, and embryonic stem cells. These cell sources, however, have raised certain questions with regard to ethical and rejection issues. Recent progress in adult stems has further proved that the cells derived from adult tissue could be expanded and differentiated into DA precursor cells in vitro, and cell therapy with adult stem cells could produce a clear improvement for PD models. Using adult stem cells for clinic application may not only overcome the ethical problem inherent in using human fetal tissue or embryonic stem cells, but also open the possibility for autologous transplantation. The patient-specific adult stem cell is therefore a potential and prospective candidate for PD treatment.