Background: Cell therapy of many neurodegenerative diseases using bone marrow stromal cells (BMSC) requires the differentiation of BMSC into neuronal subtype. However, the transdifferentiation of BMSC into GABAergic phenotype requires more investigation.

Methods: In this study, BMSC of adult female rats were pre-induced into neuroblast-like cells using 1 mM beta-mercaptoethanol (betaME) and 10 microM retinoic acid (RA), followed by 40 mM potassium chloride as inducer. The BMSC were evaluated by fibronectin as well as Oct-4. The percentage of nestin, neurofilaments (NF 68, NF 160, and NF 200) and GABA immuno-reactive cells was used to evaluate the GABAergic differentiation at the pre-induction and induction stages. The statistical analysis was carried out using unpaired student's t-test and ANOVA with Tukey's multiple comparison.

Results: The BMSC in the fourth passage expressed fibronectin up to 91.24 +/- 0.82%. The pre-induced cells after 2 days of RA exposure showed the expression of neuroblastic markers of nestin and NF68 (81.56 +/- 2.64% and 82.12 +/- 2.65%, respectively). The yield of GABAergic neurons with beta-ME for 1 h and RA as pre-inducer for 2 days followed by potassium chloride as inducer (40 mM for 3 days) was 60.64% +/- 1.97%. In addition, NF160 and NF200 were detected in the transdifferentiated cells. RT-PCR showed no expression of Oct-4 after the induction and pre-induction stages.

Conclusion: GABAergic-like neurons obtained from BMSC can be potentially used in cell transplanting for some neurodegenerative disorders.