Adult rat mesenchymal stem cells differentiate into neuronal-like phenotype and express a variety of neuro-regulatory molecules in vitro

Bone marrow stromal stem cells (MSCs), which normally differentiate into mesenchymal derivatives, have recently reported to trans-differentiate into neurons. However, the findings from different groups and interpretations have been challenged.The purpose of this paper is to re-evaluate the phenomenon of neuronal trans-differentiation of MSCs and compare the expression levels of neurotrophins in rMSCs and neuronal-like phenotypes derived from rMSCs. We put rMSCs in 2-mercaptoethanol and 2% dimethylsulfoxide for 5 h. Then, the cells were transferred to neuronal induction media composed of DMEM + 10%FBS, 10 ug/L basic fibroblast growth factor, 10 ug/L human epidermal growth factor, 1 mmol dibutyryl cyclicn AMP and 0.5 mmol isobutylmethylxanthine for 7 days and 14 days. The study demonstrated that the level of BDNF, NGF, NT3, CNTF and GDNF of rMSCs is remarkably higher in rMSCs than the neuronal-like phenotypes, especially CNTF. The expression level of these neurotrophins did not change significantly after enduring induction. We believed that rMSCs can trans-differentiate into neuronal-like phenotype under certain conditions. The non-induced rMSCs has a dynamic expression profile of neurotrophins and may serves as a better tool than the trans-differentiated rMSCs for transplant therapy.