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An in vitro technique was devised to induced autologous adult stem cells into oligodendrocyte-like cells. In this study, a protocol was developed for the induction of bone marrow stromal cells (BMSCs) into oligodendrocyte-like cells. BMSCs were incubated in one of these three pre-inducers: dimethyl sulfoxide (DMSO), β-mercaptoethanol (βME) or biotylated hydroxyanisol (BHA), each followed by retinoic acid (RA) treatment. The percentage of viable cells in BHA-RA preinduced cells was significantly lower than the others. The results showed that the preinduced cells were immunoreactive for nestin and NF-68; among the mentioned protocols, the immunoreactivity yielded by following the DMSO-RA protocol was significantly higher than the others. Moreover, no significant immunoreactivity was observed for preinduced cells to O4, O1, MBP (myelin basic protein), S100, and GFAP (glial fibrillary acidic protein). The cells were immunoreactive to oligo-2. Two phases of induction were done: the first was a combination of basic fibroblast growth factor (bFGF), platelet-derived growth factor (PDGF) and heregulin (HRG), followed by either triiodothyronine (T3) or Forskolin (FSK) as the second phase. The conclusion is that the trans-differentiation of BMSCs by DMSO followed by RA (preinduction stage) then bFGF-PDGF-HRG followed by T3 (10 ng/ml) (induction stage) can be a potential source for oligodendrocyte-like cells preparation.

Central pain is one of the most important complications after spinal cord injury (SCI), and thereby, its treatment raises many challenges. After SCI, in a cascade of molecular events, a marked increase in glutamate at the injury site results in secondary changes which may impact on supraspinal regions, mainly ventroposterolateral (VPL). There is little information about the changes in glutamate metabolism in the VPL and whether it contributes to SCI-related central pain. The present study was performed to evaluate glutamate release in the VPL following electrolytic lesion of spinothalamic tract (STT). A laminectomy was performed at spinal segments of T9-T10 in male rats, and then, unilateral electrolytic lesions were made in the STT. Glutamate concentrations in ipsilateral VPL dialysate were measured by HPLC method at days 3, 7, 14, 21 and 28 post-injury. Tactile pain and motor activity were also examined. Glutamate levels were significantly increased in ipsilateral VPL of spinal-cord-injured rats 2 weeks after SCI and remained high up to day 28 post-surgery. The STT lesions had no marked effect on our measures of motor activity, but there was a significant decrease in paw withdrawal threshold in the hind paws at day 14 post-SCI. These findings suggest that an increased release of glutamate in VPL plays a role in secondary pathologic changes, leading to neuronal hyperexcitation and neuropathic pain after SCI.

Polylactide-co-glycolide acid (PLGA) is known as a biodegradable and biocompatible polymer. This polymer has been highly used in tissue engineering. In this study, the biological behavior of Schwann cells (Rat) was investigated in co-culture with L lysine/gelatine coated PLGA nano-fiber. In this study, PLGA was dissolved in a hexafluoro propanol based solvent and nanofiber prepared by an electronic method. They were coated with gelatin and poly-L-lysine individually. These polymer properties were investigated by Scanning Electron Microscopy (SEM) analysis and contact angle measurement. After extraction of rat Schwann cells, the cells were cultured in three groups of nano-fiber; nano-fiber PLGA, nano-fiber gelatine coated PLGA and nano-fiber poly-L-lysine coated PLGA. Cell death and Cell proliferation were evaluated by Acridine orange staining (living cell with a green nucleus and dead cell with an orange nucleus) and morphology was investigated by SEM in 2, 4 and 6 days. The diameter of electronic nanofiber PLGA was between 270 to 700 nm. Average contact angles of PLGA, PLGA coated with gelatine, coated with poly-L-lysine and PLGA were 40.12, 64.58 and 107.66degrees, respectively. The findings showed a significant reduction of cell proliferation in PLGA nanofiber ( it was important than PLGA without nano-fiber (P <0.05)). But, this amount was increased in nanofiber which coated with poly-L-lysine and gelatine. PLGA nanofiber-poly-L-lysine was more biocompatible than PLGA nanofiber-gelatine and this comparison was done with rat Schwann cells.