Efficient induction of neural precursor cells from fibroblasts using stromal cell-derived inducing activity

Roles of Transcription Factors in the Development and Reprogramming of the Dopaminergic Neurons

The meso-diencephalic dopaminergic (mdDA) neurons regulate various critical processes in the mammalian nervous system, including voluntary movement and a wide range of behaviors such as mood, reward, addiction, and stress. mdDA neuronal loss is linked with one of the most prominent human movement neurological disorders, Parkinson’s disease (PD). How these cells die and regenerate are two of the most hotly debated PD research topics. As for the latter, it has been long known that a series of transcription factors (TFs) involves the development of mdDA neurons, specifying cell types and controlling developmental patterns. In vitro and in vivo, TFs regulate the expression of tyrosine hydroxylase, a dopamine transporter, vesicular monoamine transporter 2, and L-aromatic amino acid decarboxylase, all of which are critical for dopamine synthesis and transport in dopaminergic neurons (DA neurons). In this review, we encapsulate the molecular mechanism of TFs underlying embryonic growth and maturation of mdDA neurons and update achievements on dopaminergic cell therapy dependent on knowledge of TFs in mdDA neuronal development. We believe that a deeper understanding of the extrinsic and intrinsic factors that influence DA neurons’ fate and development in the midbrain could lead to a better strategy for PD cell therapy.

Hybrid Nanofiber Scaffold-Based Direct Conversion of Neural Precursor Cells/Dopamine Neurons

The concept of cellular reprogramming was developed to generate induced neural precursor cells (iNPCs)/dopaminergic (iDA) neurons using diverse approaches. Here, we investigated the effects of various nanoscale scaffolds (fiber, dot, and line) on iNPC/iDA differentiation by direct reprogramming. The generation and maturation of iDA neurons (microtubule-associated protein 2-positive and tyrosine hydroxylase-positive) and iNPCs (NESTIN-positive and SOX2-positive) increased on fiber and dot scaffolds as compared to that of the flat (control) scaffold. This study demonstrates that nanotopographical environments are suitable for direct differentiation methods and may improve the differentiation efficiency.

Neural Progenitor Cell Derivation Methodologies for Drug Discovery Applications

Inducible pluripotent stem cells (iPSCs) are being used to model brain disorders across the continuum of neurodevelopment, neurodegenerative, and neuropsychiatric disease allowing for the mechanistic unraveling of the neurological disease state. Subsequently, there is a diverse array of cell model systems that can be used for target validation, pharmacodynamic endpoint development, and high-throughput/content assay development and screening. However, to successfully model neurological disorders with iPSCs, the disease-relevant neuron must be first identified, and it is critical to have the appropriate neuronal progenitor cell derivation and neuron differentiation protocols available to produce desired neuronal phenotypes. Moreover, special considerations are necessary if adaptation to high-throughput/content assay systems is anticipated. Discussed here are the three-dimensional embryoid body-neural rosette and two-dimensional monolayer methodologies to derive iPS neural progenitor cells and neurons with a specific focus on cortical neurons. Outlined are some of the commonalities, advantages, and disadvantages associated with both methodologies.