Progress in stem cell therapy for major human neurological disorders.

Human neurological disorders such as Alzheimer's disease (AD), Parkinson's disease, stroke or spinal cord injury are caused by the loss of neurons and glial cells in the brain or spinal cord in the Central Nervous System (CNS). Stem cell technology has become an attractive option to investigate and treat these diseases. Several types of neurons and glial cells have successfully been generated from stem cells, which in some cases, have ameliorated some dysfunctions both in animal models of neurological disorders and in patients at clinical level. Stem cell-based therapies can be beneficial by acting through several mechanisms such as cell replacement, modulation of inflammation and trophic actions. Here we review recent and current remarkable clinical studies involving stem cell-based therapy for AD and stroke and provide an overview of the different types of stem cells available nowadays, their main properties and how they are developing as a possible therapy for neurological disorders.