Cell adhesion molecules CAMs are transmembrane proteins that

Cell adhesion molecules (CAMs) are transmembrane proteins that are responsible for mediating adhesion of cells to other cells and/or the extracellular matrix via their extracellular domains, while their intracellular domain interacts with the cytoskeleton. Thus, CAMs provide a direct link between the extracellular growth/guiding cues and the intracellular scaffold responsible for morphology and growth. Four subclasses of CAMs are expressed in the crf hormone Supplier [34]. Neural cell adhesion molecule (N-CAM), a multifunctional regulator for cell adhesion, intracellular signaling, and cytoskeletal dynamics [35–37], is expressed on the surface of most neural cells and plays a major role in the development of the nervous system. Stimulation of N-CAM results in the phosphorylation of extracellular signal regulated kinase I and II (ERKI/II). Integrins are αβ heterodimeric proteins with roles in adhesion to the extracellular matrix (ECM) and in cell–cell interactions [38]. They play important roles in mesoderm development, epithelial morphogenesis, neural tube closure, anchorage to ECM basal lamina and central nervous system development [39]. An important property of integrins is their capacity to cross-talk with growth factor receptors [40]. Agmatine synthesized by ADC is stored in neuronal cells, may have physiological functions as a neuromodulator [41] and exhibits protective effects both in vivo and in vitro [42–45], suggesting that availability of agmatine helps protection. A recent study report suggests that agmatine treatment to subventricular zone neural stem cells increased neurogenesis and suppressed gliogenesis through the regulation of BMPs and Smad1/5/8 expression [46], driving research on exploring the protective effects of the ADC gene [14,47,48]. This study for the first time, investigates the effect of hADC gene delivery on the stemness and cell fate commitment in hADC-mNPCs. The events were investigated by checking the expression levels of microtubule-associated protein-2 (MAP-2) and glial fibrillary acidic protein (GFAP) expressions for cell fate commitment. The morphological change induced by hADC gene delivery was investigated by checking the expression levels of adhesion molecules, N-CAM and integrin. The hADC-mNPCs showed modulation of brain-derived neurotrophic factor (BDNF), phosphoinositide 3-kinase (PI3K) and ERK1/2 expressions. Furthermore, the role of Wnt/β-catenin signaling pathway was explored by checking glycogen synthase kinase3β (GSK-3β), BMP-7, BMP-4, Smad1/5/8 and Id-1 protein expressions for the neuronal commitment of hADC-mNPCs. The effects of the induced hADC gene functions were evaluated by knocking down the ADC gene using specific siRNA.
Materials and methods
Results
Discussion The neurosphere culture system is widely used to propagate multipotent CNS precursors, but their differentiation into neurons, astrocytes and oligodendrocytes is rather poor [60,61]. Further, neural stem/precursor cells (NSPCs) have limited proliferative and neurogenic potential, which may restrict their therapeutic application [62]. Investigations to identify ways for directing stem cells towards a specific phenotype have focused on providing signals to the cells to recapitulate normal development. Mouse NSCs were directed towards dopaminergic neuronal differentiation by over-expressing Ngn2 and Nurr1 genes [63,64]. Following grafting, these cells areparticularly vulnerable and have poor survival. Hence, studies are required to enhance neurogenic potential and cell survival of the stem cells to combat the pathological conditions that prevail in the microenvironment of CNS diseases. Our earlier investigations suggested that hADCinfection to mNPCs and NIH3T3 cell line conferred protection against oxidative insult [14,48]. This present study intended to investigate whether hADC gene delivery to mNPCs could induce modulation in stem cell fate and characteristics.