The present invention is based in part methods for treating neurodegenerative diseases and disorders. Specifically, the present invention disclose methods for treating neurodegenerative disorders suing neural stem cells (NSCs) and/or pluripotent stem cell (PSC) derived neurons or neuron precursor cells. The present invention also discloses methods to induce endogenous dopaminergic neurons to release dopamine and increase the levels of dopamine in a subject.