Neuronal Transdifferentiation Potential of Human Mesenchymal Stem Cells from Neonatal and Adult Sources by a Small Molecule Cocktail.

Lorena V Cortés-Medina,Erika Hernández-Estévez,Gerardo Ramos-Mandujano,Arturo Picones,Laura C Bonifaz,M P De La Rosa Ruiz,Enoch Luis,Marco Antonio Alvarez-Perez,Herminia Pasantes-Morales,Alejandro Aguilera-Castrejon,Victor A Cortés-Morales,Juan Jose Montesinos,Cesar O Lara-Figueroa

doi:10.1155/2019/7627148

Abstract

Human mesenchymal stem cells (MSCs) are good candidates for brain cell replacement strategies and have already been used as adjuvant treatments in neurological disorders. MSCs can be obtained from many different sources, and the present study compares the potential of neuronal transdifferentiation in MSCs from adult and neonatal sources (Wharton's jelly (WhJ), dental pulp (DP), periodontal ligament (PDL), gingival tissue (GT), dermis (SK), placenta (PLAC), and umbilical cord blood (UCB)) with a protocol previously tested in bone marrow- (BM-) MSCs consisting of a cocktail of six small molecules: I-BET151, CHIR99021, forskolin, RepSox, Y-27632, and dbcAMP (ICFRYA). Neuronal morphology and the presence of cells positive for neuronal markers (TUJ1 and MAP2) were considered attributes of neuronal induction. The ICFRYA cocktail did not induce neuronal features in WhJ-MSCs, and these features were only partial in the MSCs from dental tissues, SK-MSCs, and PLAC-MSCs. The best response was found in UCB-MSCs, which was comparable to the response of BM-MSCs. The addition of neurotrophic factors to the ICFRYA cocktail significantly increased the number of cells with complex neuron-like morphology and increased the number of cells positive for mature neuronal markers in BM- and UCB-MSCs. The neuronal cells generated from UCB-MSCs and BM-MSCs showed increased reactivity of the neuronal genes TUJ1, MAP2, NF-H, NCAM, ND1, TAU, ENO2, GABA, and NeuN as well as down- and upregulation of MSC and neuronal genes, respectively. The present study showed marked differences between the MSCs from different sources in response to the transdifferentiation protocol used here. These results may contribute to identifying the best source of MSCs for potential cell replacement therapies.

Highlights

The in vitro generation of neuronal cells from neural (NSCs), embryonic (ESCs), and induced pluripotent stem cells, or by neuronal transdifferentiation of somatic cells by transcription factors (TF) has emerged as a useful strategy for cell replacement therapies in neurological disorders [1,2,3]; technical limitations, graft rejection, ethical issues, and/or tumorigenic risk are associated with the neurons derived from such processes [4,5,6]
We evaluated the neuronal-like morphology and neuronal markers induced by the ICFRYA cocktail in mesenchymal stem cells (MSCs) obtained from bone marrow (BM), skin (SK), dental pulp (DP), periodontal ligament (PDL), gingival tissue (GT), Wharton jelly (WhJ), placenta (PLAC), and umbilical cord blood (UCB)
In UCB-MSCs incubated with ICFRYA containing 2 μM I-BET151, neuronal morphology was observed after two days of induction (Figure 2(c)), notably reducing the induction time from 8 to 4 days

Summary

Introduction

The in vitro generation of neuronal cells from neural (NSCs), embryonic (ESCs), and induced pluripotent stem cells (iPSCs), or by neuronal transdifferentiation of somatic cells by transcription factors (TF) has emerged as a useful strategy for cell replacement therapies in neurological disorders [1,2,3]; technical limitations, graft rejection, ethical issues, and/or tumorigenic risk are associated with the neurons derived from such processes [4,5,6]. MSCs are potentially able to differentiate into various cell lineages (including neurons), are easy to isolate and expand, have a low tumorigenic risk and low grafting rejection, and lack ethical issues [12,13,14,15]. These properties point to MSCs as suitable sources for cell replacement therapy in neurological disorders [16,17,18,19]; an optimal protocol to induce their conversion into neurons remains unestablished. After a small molecule screening assay, we found that a cocktail containing I-BET151, CHIR99021, forskolin, RepSox, Y-27632, and cAMP (ICFRYA) induced the formation of cells with neuron-like morphology and positive for TUJ1 and MAP2 from bone marrow- (BM-) MSCs [10]

Methods

Results

Conclusion