Transcriptional Characterization of Wnt and Notch Signaling Pathways in Neuronal Differentiation of Human Adipose Tissue-Derived Stem Cells

Since the nervous system has limited self-repair capability, a great interest in using stem cells is generated to repair it. The adipose tissue is an abundant source of stem cells and previous reports have shown the differentiation of them in neuron-like cells when cultures are enriched with growth factors involved in neurogenesis. Regarding this, it could be thought that a functional parallelism between neurogenesis and neuronal differentiation of human adipose stem cells (hASCs) exists. For this reason, we investigated the putative involvement of Notch and Wnt pathways in neuronal differentiation of hASCs through real-time PCR. We found that both Wnt and Notch signaling are present in proliferating hASCs and that both cascades are downregulated when cells are differentiated to a neuronal phenotype. These results are in concordance with previous works where it was found that both pathways are involved in the maintenance of the proliferative state of stem cells, probably through inhibition of the expression of cell-fate-specific genes. These results could support the notion that hASCs differentiation into neuron-like cells represents a regulated process analogous to what occurs during neuronal differentiation of NSCs and could partially contribute to elucidate the molecular mechanisms involved in neuronal differentiation of adult human nonneural tissues.