Transforming Growth Factor-β and Notch Signaling Mediate Stem Cell Differentiation into Smooth Muscle Cells

Abstract

The differentiation of stem cells into smooth muscle cells (SMCs) plays an important role in vascular development and remodeling. In addition, stem cells represent a potential source of SMCs for regenerative medicine applications such as constructing vascular grafts. Previous studies have suggested that various biochemical factors, including transforming growth factor-β (TGF-β) and the Notch pathway, may play important roles in vascular differentiation. However, the interactions of these two signaling pathways in the differentiation of bone marrow mesenchymal stem cells (MSCs) have not been clearly defined. In this study, we profiled the gene expression in MSCs in response to TGF-β, and showed that TGF-β induced Notch ligand Jagged 1 (JAG1) and SMC markers, including smooth muscle α-actin (ACTA2), calponin 1 (CNN1), and myocardin (MYOCD), which were dependent on the activation of SMAD3 and Rho kinase. In addition, knocking down JAG1 expression partially blocked ACTA2 and CNN1 expression and completely blocked MYOCD expression, suggesting that JAG1 plays an important role in TGF-β-induced expression of SMC markers. On the other hand, the activation of Notch signaling induced the expression of SMC markers in MSCs and human embryonic stem cells (hESCs). Notch activation in hESCs also resulted in an increase of neural markers and a decrease of endothelial markers. These results suggest that Notch signaling mediates TGF-β regulation of MSC differentiation and that Notch signaling induces the differentiation of MSCs and hESCs into SMCs, which represents a novel mechanism involved in stem cell differentiation.

Insights into the Role of Focal Adhesion Modulation in Myogenic Differentiation of Human Mesenchymal Stem Cells

“…4a, only upregulation of MLCK was observed. SMA and ACTA1, which were smooth/skeletal muscle markers for smooth/skeletal muscle differentiation [38], were not upregulated. It corresponded well with the real-time PCR result in Fig.…”

NOTCH activation interferes with cell fate specification in the gastrulating mouse embryo

“…Inducible activation of NICD in mESCs cultured under mesoderm differentiation conditions leads to a reduction of endothelial, haematopoietic and cardiac differentiation and favours the generation of smooth muscle cells (SMC) (Nemir et al, 2006;Schroeder et al, 2003Schroeder et al, , 2006. Activation of the NOTCH pathway in human mesenchymal or ESCs similarly induces SMC differentiation (Kurpinski et al, 2010). In the chick embryo, NOTCH activity in the ventral mesoderm mediates the balance between blood or endothelial and smooth muscle progenitors, and promotes the formation of the latter (Shin et al, 2009).…”

“…NOTCH activity is notably required to maintain a pool of neural progenitors and to inhibit further neural differentiation, but can also regulate the acquisition of distinct cell fates by promoting gliogenesis or influencing binary fate choices during neurogenesis (reviewed by Pierfelice et al, 2011;Yoon and Gaiano, 2005). A role for the NOTCH pathway during early neural specification has been pinpointed by gain-and loss-of-function in vitro analyses showing that NOTCH activity promotes neural lineage commitment in pluripotent ESCs (Das et al, 2010;Kurpinski et al, 2010;Lowell et al, 2006). In order to investigate whether the NOTCH pathway can also play such an early role during in vivo neural development, we analysed the formation of neurectodermal tissue in N1ICD epi embryos.…”

“…However, canonical NOTCH signalling has been shown to regulate lineage commitment when ESCs are induced to differentiate. Constitutive expression of NICD in mESCs or treatment of hESCs with DLL1-expressing feeders favours the acquisition of a neurectodermal fate (Das et al, 2010;Kurpinski et al, 2010;Lowell et al, 2006). By contrast, inactivation of the NOTCH pathway with a γ-SECRETASE inhibitor or via genetic deletion of Notch1 and Rbpj accelerates ESC differentiation towards mesoderm, and enhances their cardiogenic potential (Jang et al, 2008;Nemir et al, 2006;Schroeder et al, 2003).…”

Novel Adult Stem Cells for Peripheral Nerve Regeneration

“…3h-l), which further confirmed that EGFP − cells in tunica media were MVSCs. To determine whether MVSCs could differentiate into mature SMCs and turn on EGFP expression, we activated Notch signalling by co-culturing EGFP − MVSCs with OP9-Delta1 feeder cells 34 . After 2 weeks of co-culture, majority of the MVSCs showed strong green fluorescence (Fig.…”