Advances in Pluripotent Stem Cells: History, Mechanisms, Technologies, and Applications.

Over the past 20 years, and particularly in the last decade, significant developmental milestones have driven basic, translational, and clinical advances in the field of stem cell and regenerative medicine. In this article, we provide a systemic overview of the major recent discoveries in this exciting and rapidly developing field. We begin by discussing experimental advances in the generation and differentiation of pluripotent stem cells (PSCs), next moving to the maintenance of stem cells in different culture types, and finishing with a discussion of three-dimensional (3D) cell technology and future stem cell applications.

Restoring Motor Neurons in Spinal Cord Injury With Induced Pluripotent Stem Cells.

Spinal cord injury (SCI) is a devastating neurological disorder that damages motor, sensory, and autonomic pathways. Recent advances in stem cell therapy have allowed for the generation of motor neurons (MNs) showing electrophysiological and synaptic activity, expression of canonical MN biomarkers, and the ability to graft into spinal lesions. Clinical translation, especially the transplantation of MN precursors in spinal lesions, has thus far been elusive because of stem cell heterogeneity and protocol variability, as well as a hostile microenvironment such as inflammation and scarring, which yield inconsistent pre-clinical results without a consensus best-practice therapeutic strategy.

Use of induced pluripotent stem cell derived neurons engineered to express BDNF for modulation of stressor related pathology.

Combined cell and gene-based therapeutic strategies offer potential in the treatment of neurodegenerative and psychiatric conditions that have been associated with structural brain disturbances. In the present investigation, we used a novel virus-free re-programming method to generate induced pluripotent stem cells (iPSCs), and then subsequently transformed these cells into neural cells which over-expressed brain derived neurotrophic factor (BDNF). Importantly, the infusion of iPSC derived neural cells (as a cell replacement and gene delivery tool) and BDNF (as a protective factor) influenced neuronal outcomes.

Paradigm of genetic mosaicism and lone atrial fibrillation: physiological characterization of a connexin 43-deletion mutant identified from atrial tissue.

Background: Atrial fibrillation (AF) is the most common sustained arrhythmia observed in otherwise healthy individuals. Most lone AF cases are nonfamilial, leading to the assumption that a primary genetic origin is unlikely. In this study, we provide data supporting a novel paradigm that atrial tissue-specific genetic defects may be associated with sporadic cases of lone AF.

Gain-of-function mutation of Nav1.5 in atrial fibrillation enhances cellular excitability and lowers the threshold for action potential firing.

Genetic mutations of the cardiac sodium channel (SCN5A) specific only to the phenotype of atrial fibrillation have recently been described. However, data on the biophysical properties of SCN5A variants associated with atrial fibrillation are scarce. In a mother and son with lone atrial fibrillation, we identified a novel SCN5A coding variant, K1493R, which altered a highly conserved residue in the DIII-IV linker and was located six amino acids downstream from the fast inactivation motif of sodium channels.

A teleost in vitro reporter gene assay to screen for agonists of the peroxisome proliferator-activated receptors.

Several contaminants detected in aquatic ecosystems are agonists of peroxisome proliferator-activated receptors (PPARs). Peroxisome proliferator-activated receptors interact with the retinoid X receptor (RXR) to activate the transcription of genes that control a variety of physiological functions. We cloned and sequenced partial cDNA fragments of rainbow trout (Oncorhynchus mykiss) PPARalpha and PPARbeta from rainbow trout (rt) gill-W1 cells, a cell line derived from rainbow trout gills; predicted amino acid identities are 77% and 82% compared with their respective human homologs and 83 to 88% and 91 to 98% identical to fish homologs.

Diacylglycerol and ceramide formation induced by dopamine D2S receptors via Gbeta gamma -subunits in Balb/c-3T3 cells.

Diacylglycerol (DAG) and ceramide are important second messengers affecting cell growth, differentiation, and apoptosis. Balb/c-3T3 fibroblast cells expressing dopamine-D2S (short) receptors (Balb-D2S cells) provide a model of G protein-mediated cell growth and transformation. In Balb-D2S cells, apomorphine (EC(50) = 10 nM) stimulated DAG and ceramide formation by 5.

Growth hormone-induced diacylglycerol and ceramide formation via Galpha i3 and Gbeta gamma in GH4 pituitary cells. Potentiation by dopamine-D2 receptor activation.

Growth hormone (GH) secretion is regulated by indirect negative feedback mechanisms. To address whether GH has direct actions on pituitary cells, lipid signaling in GH(4)ZR(7) somatomammotroph cells was examined. GH (EC(50) = 5 nm) stimulated diacylglycerol (DAG) and ceramide formation in parallel by over 10-fold within 15 min and persisting for >3 h.

Bradykinin stimulates ceramide production by activating specific BK-B(1) receptor in rat small artery.

Bradykinin (BK), a proinflammatory factor and vasodilator, causes functional change of the small artery. However, it is not clear whether any of these changes induced by BK are mediated by N-acetyl-D-sphingosine (ceramide). Therefore, we investigated whether BK affects the hydrolysis of sphingomyelin and generation of ceramide in the intact rat small artery.