Neural Transdifferentiation of embryonic like stem cells by lithium chloride

Spermatogonial stem cells (SSCs) because of its ability to be reprogrammed into embryonic-like stem cells (ELSCs) can be a new source of pluripotent stem cells which can play a promising role in regenerative medicine. In this study, SSCs were transdifferentiated into neuron-like cells (NLCs) using two-step differentiation protocol. pluripotency and germ cells markers were analyzed in SSCs and ELSCs. Also neural markers were analyzed in ELSCs and NLCs.

Neonatal rat testes were mechanically dissected and digested then was cultured in DMEM supplemented with 15% FBS. The medium was replaced with DMEM containing LIF, mercaptoethanol, EGF, bFGF, and GDNF. After 5 weeks, ELSCs colonies appeared. SSCs and ELSCs were evaluated by Stra8, plzf (germ cells markers) Oct4, and sox2 (pluripotency markers) using qRT-PCR. The ELSCs colonies were isolated and cultured in DMEM containing 0.5 mM lithium chloride. In day 5, ELSCs transdifferentiated to NLC. They were evaluated using neural marker including Neurofilament 200 (NF-200), choline acetyltransferase (CAT), synaptophysin (Syp), Nestin (Nes), Neurogenin1 (NG1), Neurod1 (Nd1), and Neurofilament 68 (NF-68)gene expression.

Result showed increasing expression of Oct4 and sox2 genes and low level of Stra8 and plzf expression in ELSCs than SSCs. After neural transdifferentiation by lithium chloride induction, neural markers were examined by RT-PCR in ELSCs and NLCs. The result showed expression of NF-200, CAT, Syp, Nes, NG1, Nd1 and NF-68 in NLCs opposed to ELSCs.

This study indicates lithium chloride can promote ELSCs to transdifferentiate into NLCs.