The generation of dopaminergic neurons by human neural stem cells is enhanced by Bcl-XL, both in vitro and in vivo.
Progress in stem cell biology research is enhancing our ability to generate specific neuron types for basic and applied studies and to design new treatments for neurodegenerative diseases. In the case of Parkinson's disease (PD), alternative human dopaminergic (DAergic) neurons other than primary fetal tissue do not yet exist. One possible source could be human neural stem cells (hNSCs), although the yield in DAergic neurons and their survival are very limited. [see figure]. In this study, we found that Bcl-X(L) enhances (one-to-two orders of magnitude) the capacity for spontaneous dopaminergic differentiation of hNSCs, which then exceeds that of cultured human ventral mesencephalic tissue. Bcl-X(L) also enhanced total neuron generation by hNSCs, but to a lower extent. Neuronal phenotypes other than DA were not affected by Bcl-X(L), indicating an exquisitely specific effect on DAergic neurons. In vivo, grafts of Bcl-X(L)-overexpressing hNSCs do generate surviving human TH+ neurons in the adult rat 6-OH-dopamine lesioned striatum, something never seen when naive hNSCs were transplanted. Most of the data obtained here in terms of the effects of Bcl-X(L) are consistent with an enhanced survival type of mechanism and not supportive of induction, specification, or proliferation of DAergic precursors. From this in vitro and in vivo evidence, we conclude that enhancing Bcl-X(L) expression is important to obtain human DAergic neurons from hNSCs. These findings may facilitate the development of drug-screening and cell-replacement activities to discover new therapeutic strategies for PD.
Liste
Isabel
I
Center of Molecular Biology Severo Ochoa, Autonomous University of Madrid, 28049 Madrid, Spain.
García-García
Elisa
E
Martínez-Serrano
Alberto
A
D000818:Animals; D017209:Apoptosis; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics / Q000502:physiology; D002454:Cell Differentiation; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured / Q000187:drug effects / Q000378:metabolism / Q000637:transplantation; D003342:Corpus Striatum / Q000187:drug effects; D004298:Dopamine / Q000378:metabolism*; D005260:Female; D051100:Glial Cell Line-Derived Neurotrophic Factor; D006085:Graft Survival / Q000187:drug effects; D006801:Humans; D008636:Mesencephalon / Q000166:cytology; D009414:Nerve Growth Factors / Q000235:genetics / Q000502:physiology; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000502:physiology*; D009474:Neurons / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D018384:Oxidative Stress; D016627:Oxidopamine / Q000633:toxicity; D010641:Phenotype; D016548:Prosencephalon / Q000166:cytology / Q000196:embryology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D011993:Recombinant Fusion Proteins / Q000502:physiology; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism; D013482:Superoxide Dismutase / Q000235:genetics / Q000502:physiology; D014162:Transfection; D014183:Transplantation, Heterologous; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis / Q000235:genetics; D051020:bcl-X Protein
C494811:BCL2L1 protein, human; C494813:Bcl2l1 protein, rat; D019208:Brain-Derived Neurotrophic Factor; C495039:GDNF protein, human; C495041:Gdnf protein, rat; D051100:Glial Cell Line-Derived Neurotrophic Factor; D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D011993:Recombinant Fusion Proteins; D051020:bcl-X Protein; D016627:Oxidopamine; D014446:Tyrosine 3-Monooxygenase; D013482:Superoxide Dismutase; D004298:Dopamine