RESUMO
<p><b>OBJECTIVE</b>To investigate the differentiation potential of rat adipose tissue-derived cells (ADSCs) into neuron-like cells in vitro using a two-step induction protocol.</p><p><b>METHODS</b>ADSCs isolated from the epididymal fat pads in male SD rats by means of differential attachment were cultured in vitro and subjected to adipogenic induction. After flow cytometric identification of the cell surface antigens CD106, CD11b, CD45, CD49d, CD90 and CD29, the third-passage ADSCs were induced to transdifferentiate into neural stem cell (NSC)-like cells in DMEM/F12 medium containing 10 ng/ml basic fibroblast growth factor (bFGF), 20 ng/ml epidermal growth factor (EGF) and 2% B27. The resultant NSC-like cells were then induced to differentiate into neuron-like cells in the neurobasal medium containing 10 ng/ml brain-derived neurotrophic factor (BDNF), 10 ng/ml glial cell line-derived neurotrophic factor (GDNF) and 1 µmol/L retinoic acid (RA). Immunocytochemistry was employed to identify the expression of the cell surface markers nestin, MAP2 and NeuN.</p><p><b>RESULTS</b>The isolated ADSCs were positive for CD90 and CD29, and oil red O staining of the induced adipose-like cells yielded positive results. The third-passage ADSCs induced for 7 days aggregated as floating cell spheres positive for NSC surface antigen nestin. Further induction in neurobasal medium for 4 h resulted in adhesion of the cell spheres and the formation of cell processes extending from some peripheral cells, suggesting a morphological resemblance to neurons. Most of the cells showed positivity for MAP2 and NeuN.</p><p><b>CONCLUSION</b>ADSCs can be induced to differentiate into neuron-like cells in vitro under appropriate conditions.</p>