Objective To study the growth characteristics of umbil ical cord MSCs (UCMSCs) in vitro and its effect on the nerve regeneration after spinal cord injury (SCI). Methods UCMSCs isolated from pregnant rats umbil ical cord were cultured and purified in vitro. Sixty female Wistar rats weighing (300 ± 10) g were randomized into three groups (n=20per group). UCMSCs group (group A) in which UCMSCs suspension injection was conducted; DMEM control group (groupB) in which 10% DMEM injection was conducted; sham group (group C) in which the animal received laminectomy only.Establ ish acute SCI model (T10) by Impactor model-II device in group A and group B. The recovery of the lower extremity was observed using BBB locomotor scoring system, neurofilament 200 (NF-200) immunofluorescence staining was performed to detect the neural regeneration, and then the corticospinal tract (CST) was observed using the biotinylated dextran amine (BDA) tracing. Results Cultured UCMSCs were spindle-shaped fibrocyte-l ike adherent growth, swirl ing or parallelly. The USMSCs expressed CD29, but not CD31, CD45, and HLA-DR. The BBB score was higher in group A than group B 4, 5, and 6 weeks after operation, and there was a significant difference between two groups (P lt; 0.05). The BBB scores at different time points were significantly lower in groups A and B than that in group C (P lt; 0.05). UCMSCs was proved to survive and assemble around the injured place by frozen section of the cords 6 weeks after injury. NF-200 positive response area in groups A, B, and C was (11 943 ± 856), (7 986 ± 627), and (13 117 ± 945) pixels, respectively, suggesting there was a significant difference between groups A, C and group B (P lt; 0.05), and no significant difference was evident between group A and group C (P gt; 0.05). BDA anterograde tracing 10 weeks after operation demonstrated that more regenerated nerve fibers went through injured area in group A, but just quite few nerve fibers in group B went through the injuried cavity. The ratios of regenerative axons amount to T5 axons in group A and group B were smaller than that of group C (P lt; 0.05). Conclusion UCMSCs can prol iferate rapidly in vitro, survive and differentiate to neurons after being grafted into injured spinal cord. The transplantation of UCMSCs is effective in promoting functional recovery and axonal regeneration after SCI.
ObjectiveTo investigate the effects of bone marrow mesenchymal stem cells (BMSCs) transplantation for treating spinal cord injury (SCI) in rat and the cytokine expression changes in the local injury tissues. MethodsBMSCs were separated from Sprague Dawley (SD) rat and cultured with the whole bone marrow culture method. rAd-EGFP was used to transfect the 5th generation BMSCs for green fluorescent protein (GFP) label. Twelve SD rats were randomly divided into experimental group (n=6) and control group (n=6). After the T10 SCI model was established with Allen's impact device in 2 groups, 1×106 GFP-labeled BMSCs and PBS were administered by subarachnoid injection in situ in experimental group and control group, respectively. Basso-Beattie-Bresnahan (BBB) score was used to detect the motor function at immediat, 1, 2, 3, 4, and 5 weeks after SCI. At 5 weeks, the spinal cord tissues were harvested for the histological and immunofluorescent staining examinations to measure the expressions of neural marker molecules, including Nestin, glial fibrillary acidic protein (GFAP), and neuron-specific nuclear protein (NeuN). Cytokine was analyzed with antibody array. ResultsAt 5 weeks, 2 rats died of urinary tract infection in 2 groups respectively, the other rats survived to the end of experiment. BBB score of experimental group was significantly higher than that of control group at 1, 2, 3, 4, and 5 weeks (P < 0.05). At 5 weeks, histological results showed that there were many cells with regular arrangement in the experimental group; there were less cells with irregular arrangement in the control group. Compared with the control group, Nestin and NeuN expressions significantly increased (P < 0.05), and GFAP expression significantly decreased (P < 0.05) in the experimental group. Leptin and ciliary neurotrophic factor levels were higher in the experimental group than the control group, but granulocyte-macrophage colony-stimulating factor, tumor necrosis factorα, interleukin 1β, and tissue inhibitor of metalloproteinases 1 levels were lower in the experimental group than the control group. ConclusionBMSCs transplantation can improve survival and regeneration of nerve cells and enhances the recovery of nerve function by regulating secretion of cytokines from grafted BMSCs.
Age is the main cause of neurodegenerative changes in the central nervous system (CNS), and the loss of neurons would increase with the migration of the disease. The current treatment is also mainly used to relieve symptoms, while the function of CNS is very difficult to recover. The emergence of endogenous stem cells has brought new hope for the treatment of CNS diseases. However, this nerve regeneration is only in some specific areas, and the recovery of neural function remains unknown. More and more experts in the field of neuroscience have carried out various in vivo or in vitro experiments, in order to increase nerve regeneration and nerve function recovery through mechanism research, in the expectation that the results would be applied to the treatment of CNS diseases. This article reviews the recent progress of endogenous neural stem cells in degenerative diseases of CNS.