“…The scarce numbers of adult NSCs or their aberrant alterations in neurodegenerative diseases suppose the lack of a reliable endogenous mechanism to replenish neurons in the event of their loss. Not in vain, stem cells offer the potential to reduce deleterious signaling and improve traumatic lesions [ 28 , 29 ], and also to slowdown the progression of devastating neurodegenerative diseases such as Huntington’s (HD) [ 30 , 31 ], Parkinson’s (PD) [ 32 , 33 ] or Alzheimer’s disease (AD) [ 34 , 35 , 36 ]. The idea of using stem cells to treat neurodegenerative diseases was proposed very long ago, obtaining valuable and abundant data using fetal human tissue [ 31 , 37 , 38 ] or induced pluripotent stem cells (IPSCs) [ 39 , 40 ].…”