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.
OBJECTIVE: To explore the potential possibility of synaptic connection and 3D adhesion between fetal spinal cord cell suspension (FSCS) and host, and to observe the synapses developing process of FSCS transplantation. METHODS: Spinal cord injury model produced in 42 Wistar rats on T7 by use of modified Allen’s impact method (10 g x 5 cm); 3 days after injury, 20 microliters FSCS with a density of 1 x 10(5)/microliter prepared from E14 rat were injected into the epicenter of the traumatized cavity. Animals were sacrificed after 2, 4, 6, 8, 10 and 12 weeks of transplantation, the graft survival, its differentiation and integration with the host were observed by light and electronmicroscopic study as well as immunohistochemical assay (NF, GFAP, CGRP, 5-HT). RESULTS: In the transplantation area, the neuroblasts stretched out the terminal endings 4 weeks after implantation, followed by the presenting of the pre- and postsynaptic membrane. After 8 weeks, the dense or developed projections were observed in the pre- and postsynaptic membrane; the synaptic cleft filled with the high electron dense substance. All the spherical clear vesicles, granular vesicles, elliptical vesicles and flattened-f type vesicles were seen under the electronmicroscope. After 10 weeks, the axosomatic, dendrosomatic, dendro-dendritic, axo-axonic, dendro-axonic synapses coexisted. Light microscopy showed that the graft cell grew gradually. Immunohistochemical assay showed that NF, 5-HT, CGRP and GFAP positive fibers were in the graft. Synapses, gliafibers and blood brain barrier integrated each other. CONCLUSION: (1) The transplanted FSCS can develop mature synapses with miscellaneous synaptic vesicles in the acute injured spinal cord, host injury cavity wall may induce the FSCS into 3D adhesion. (2) Co-existence of different type of synapse and the immunohistochemistry findings indicate the possibility of synaptic connection between FSCS and host.
Objective To investigate the effect of chondroitinase ABC (ChABC) on the expression of growth associated protein 43 (GAP-43) and gl ial fibrillary acidic protein (GFAP) after spinal cord injury (SCI) in rats. Methods A total of 150 adult female SD rats, weighing 250-300 g, were randomly divided into ChABC treatment group (group A), sal ine treatment group (group B), and sham operation group (group C) with 50 rats in each group. In groups A and B, the rats were made the SCI models and were treated by subarachnoid injection of ChABC and sal ine; in group C, the rats were not treated as a control. At 1, 3, 7, 14, and 21 days after operation, the Basso, Beattie, and Bresnahan (BBB) score system was used toevaluate the motion function, and immunofluorescent histochemical staining was used to observe the expressions of GAP-43 and GFAP. Results At different time points, the BBB scores of groups A and B were significantly lower than those of group C (P lt; 0.05); there was no significant difference in BBB score between groups A and B after 1, 3, and 7 days of operation (P gt; 0.05), but the BBB score of group A was significantly higher than that of group B after 14 and 21 days of operation (P lt; 0.01). At different time points, the GAP-43 and GFAP positive neurons of groups A and B were significantly higher than those of group C (P lt; 0.05). After 14 and 21 days of operation, the GAP-43 positive neurons of group A were more than those of group B (P lt; 0.01). After 7, 14, and 21 days of operation, the GFAP positive neurons of group A were significantly less than those of group B (P lt; 0.01). Conclusion ChABC can degrade gl ial scar, improve the microenvironment of the injured region and enhance the expression of GAP-43, which promotes axonal growth and extension.
Objective To investigate the effect of chondroitinase ABC (ChABC) on the expression of growth associated protein 43 (GAP-43) and gl ial fibrillary acidic protein (GFAP) after spinal cord injury (SCI) in rats. Methods A total of 150 adult female SD rats, weighing 250-300 g, were randomly divided into ChABC treatment group (group A), sal ine treatment group (group B), and sham operation group (group C) with 50 rats in each group. In groups A and B, the rats were made the SCI models and were treated by subarachnoid injection of ChABC and sal ine; in group C, the rats were not treated as a control. At 1, 3, 7, 14, and 21 days after operation, the Basso, Beattie, and Bresnahan (BBB) score system was used toevaluate the motion function, and immunofluorescent histochemical staining was used to observe the expressions of GAP-43 and GFAP. Results At different time points, the BBB scores of groups A and B were significantly lower than those of group C (P lt; 0.05); there was no significant difference in BBB score between groups A and B after 1, 3, and 7 days of operation (P gt; 0.05), but the BBB score of group A was significantly higher than that of group B after 14 and 21 days of operation (P lt; 0.01). At different time points, the GAP-43 and GFAP positive neurons of groups A and B were significantly higher than those of group C (P lt; 0.05). After 14 and 21 days of operation, the GAP-43 positive neurons of group A were more than those of group B (P lt; 0.01). After 7, 14, and 21 days of operation, the GFAP positive neurons of group A were significantly less than those of group B (P lt; 0.01). Conclusion ChABC can degrade gl ial scar, improve the microenvironment of the injured region and enhance the expression of GAP-43, which promotes axonal growth and extension.
Objective To construct and screen neurite outgrowth inhibitory 66-samll interfering RNA (nogo66-siRNA) eukaryotic expression vectors of effective interference, so as to lay a foundation for further reconstruction of related viral vector. Methods? The nogo66-siRNA fragments were designed and cloned into pGenesil-1.1, 4 plasmids of pGenesil-nogo66-siRNA-1, pGenesil-nogo66-siRNA-2, pGenesil-nogo66-siRNA-hk, and pGenesil-nogo66-siRNA-kb were obtained, sequenced and identified, then were transfected into C6 cell l ine. The transfection efficiency was measured by fluorescence microscope. RT-PCR and Western blot were used to detect the expression of nogo gene and select the plasmid of effective interference. Results DNA sequencing results showed interference sequences were correct. The bands of 800 bp and 4.3 kb were detected when pGenesil-nogo66-siRNAs were digested by Kpn I /Xho I. The expression of green fluorescent protein could be detected under fluorescence microscope, and the transfection efficiency was about 73%. RT-PCR and Western blot results showed that compared to non-transfected cells, the transfection of pGenesil-nogo66-siRNA-1 made the expression of nogo gene decl ine 22% and the expression of nogo protein decl ine 73%; the transfection of pGenesil-nogo66-siRNA-2 made the expression of nogo gene decl ine 28% and the expression of nogo protein decl ine 78%; the differences were significant (P lt; 0.05); and the transfection of pGenesil-nogo66-siRNA-hk and pGenesil-nogo66- siRNA-kb did not make the expressions of nogo gene and nogo protein decrease significantly (P gt; 0.05). Conclusion Nogo66-siRNA eukaryotic expression vector is successfully constructed, it lays an experimental foundation for repair of spinal cord injury.
Objective To investigate a new composite matrix (BMSCs seeded on the denuded human amniotic membrane, BMSCs-DHAM) bridging the both stumps of spinal cord injury in rats to promote axon regeneration and improve motor function of hind l imbs. Methods The human amniotic membrane (HAM) was voluntarily donated by the healthy pregnant women after a caesarean section. The cells on the HAM were completely removed with a tryptic and mechanical approach to prepare DHAM. The BMSCs were separated and cultured from 4-week-old female rats (n=4), then the forth passage of BMSCs were labeled by PKH26 and seeded on DHAM (BMSCs-DHAM). The growing state of BMSCs was observed under themicroscopy. Moreover, 40 female rats (8-week-old, weighting 200-220 g) were made spinal cord injury models by transecting at T9 level, and were randomly divided into 4 groups (each group, n=10). The both stumps were respectively wrapped by BMSCs- DHAM or simple DHAM in groups A and C, and the same dose of BMSCs or physiological sal ine were also respectively injected the central lesion in groups B and D. At 12 weeks after surgery, the functional recovery of the hindl imbs was evaluated by the BBB locomotor rating score, and other indexes were tested including cortical motion evoked potential (MEP), anterograde biopinylated dextan amine (BDA) tracing, and immunofluorescence of neurofilament protein 200 (NF-200). Results HE staining proved that the DHAM was devoid of cellular components by this way, and BMSCs grew well on the substrate under the microscopy. At 12 weeks after operation, the BBB score (12.50 ± 1.26) in group A was significantly higher than those of other groups (P lt; 0.05), and the recovery in latency (3.52 ± 2.45) ms and ampl itude (480.68 ± 18.41) μV of MEP was also obviously improved in group A (P lt; 0.05) when compared with other groups. In addition, anterograde BDA tracing revealed that the rate of the positive BDA axons 54.12% ± 3.30% under the lesion level in group A was higher than those of other groups (P lt; 0.05), and lots of the regeneration axons (positive NF-200) were found to grow into the spinal cord under the composite matrix in group A. Conclusion The BMSCs-DHAM composite matrix can improve hindl imb motor function to some extent after spinal cord injury. It will be widely appl ied as the matrix material in the future.
Spinal cord injuries (SCI) seriously impair the quality of life, functional status, and social independence of the patients. Since the last century, a series of basic research on spinal cord injury has made us a deep understanding of its mechanisms and pathophysiology. But so far, how to repair damaged nerve functions after SCI is still a neurological problem. There are still controversies surrounding some treatment strategies for SCI, including the use of magnetic resonance imaging, type and timing of anticoagulant prevention, the timing of surgical intervention, the use of corticosteroids such as methylprednisolone sodium, as well as the type and timing of rehabilitation. For patients with SCI, early surgical intervention and neuroprotective therapy may be the best treatment. At the same time, rehabilitation and psychological intervention are equally important.
ObjectiveTo observe the effect of transplantation of neural stem cells (NSCs) induced by all-trans-retinoic acid (ATRA) combined with glial cell line derived neurotrophic factor (GDNF) and chondroitinase ABC (ChABC) on the neurological functional recovery of injured spinal cord in Sprague Dawley (SD) rats.
MethodsSixty adult SD female rats, weighing 200-250 g, were randomly divided into 5 groups (n=12): sham operation group (group A), SCI model group (group B), NSCs+GDNF treatment group (group C), NSCs+ChABC treatment group (group D), and NSCs+GDNF+ChABC treatment group (group E). T10 segmental transversal injury model of the spinal cord was established except group A. NSCs induced by ATRA and marked with BrdU were injected into the site of injury at 8 days after operation in groups C-E. Groups C-E were treated with GDNF, ChABC, and GDNF+ChABC respectively at 8-14 days after operation;and group A and B were treated with the same amount of saline solution. Basso Beattie Bresnahan (BBB) score and somatosensory evoked potentials (SEP) test were used to study the functional improvement at 1 day before remodeling, 7 days after remodeling, and at 1, 2, 5, and 8 weeks after transplantation. Immunofluorescence staining and HE staining were performed to observe the cells survival and differentiation in the spinal cord.
ResultsFive mouse died but another rats were added. At each time point after modeling, BBB score of groups B, C, D, and E was significantly lower than that of group A, and SEP latent period was significantly longer than that of group A (P<0.05), but no difference was found among groups B, C, D, and E at 7 days after remodeling and 1 week after transplantation (P>0.05). BBB score of groups C, D, and E was significantly higher than that of group B, and SEP latent period was significantly shorter than that of group B at 2, 5, and 8 weeks after transplantation (P<0.05);group E had higher BBB score and shorter SEP latent period than groups C and D at 5 and 8 weeks, showing significant difference (P<0.05). HE staining showed that there was a clear boundary between gray and white matter of spinal cord and regular arrangement of cells in group A;there were incomplete vascular morphology, irregular arrangement of cells, scar, and cysts in group B;there were obvious cell hyperplasia and smaller cysts in groups C, D, and E. BrdU positive cells were not observed in groups A and B, but could be found in groups C, D and E. Group E had more positive cells than groups C and D, and difference was significant (P<0.05). The number of glial fibrillary acidic protein positive cells of groups C, D, and E was significantly less than that of groups A and B, and it was significantly less in group E than groups C and D (P<0.05). The number of microtubule-associated protein 2 positive cells of groups C, D, and E was significantly more than that of groups A and B, and it was significantly more in group E than groups C and D (P<0.05).
ConclusionThe NSCs transplantation combined with GDNF and ChABC could significantly promote the functional recovery of spinal cord injury, suggesting that GDNF and ChABC have a synergistic effect in the treatment of spinal cord injury.
Objective
To observe the structural changes of urinary center and the expression of Bcl-2 after conus medullaris injury in rats brain so as to explore the possible influence factors of degeneration in brain.
Methods
Thirty-six adult Sprague-Dawley rats were randomly divided into experimental group (n=30) and control group (n=6). In the experimental group, the conus medullaris injury model was established by cutting off the spinal nerve below L4, and no treatment was done in the control group. The modeling operations in the experimental group were successful, and 2 rats died at 3 months and 5 months after modeling operation respectively, which may be caused by renal failure or urinary tract infection. In the experimental group, 6, 6, 6, 5, and 5 rats were killed at 1 day, 1 week, and 1, 3, 6 months after operation respectively, and 1 rat was killed at each time point in the control group. The dorsolateral tissue of the pontine tegmentum was harvested to perform HE staining and Bcl-2 immunohistochemical SP staining.
Results
HE staining showed that there was no obvious difference between the experimental group and the control group at 1 day after operation, the neurons were densely packed, arranged neatly, and the nucleoli were clear; at 1 week, the space between the neurons in the experimental group were slightly widened; at 1 month, nucleus retraction in some neurons happened in the experimental group; at 3 and 6 months, the nuclei in the experimental group were more and more condensed, and even some cells disappeared. Bcl-2 immunohistochemical SP staining showed that the expression of Bcl-2 in the control group was weakly positive. The positive expression of Bcl-2 was found at 1 day after operation in the experimental group; the positive expression of Bcl-2 at 7 days after operation was significantly higher than that in the control group, and reached the peak; the positive expression of Bcl-2 decreased gradually at 1, 3, and 6 months after modeling operation, but it was still higher than that of the control group.
Conclusion
The urinary center appears structure degeneration and necrocytosis after conus medullaris injury in rats brain. The elevated expression of Bcl-2 may be associated with brain tissue repair and function remodeling.
ObjectiveTo investigate the effect of continuous occupational therapy (OT) on the life satisfaction of patients with spinal cord injury (SCI). MethodsFifty-two SCI patients treated in Department of Rehabilitation at People’s Hospital of Mianzhu City between 2008 and 2010 were randomly assigned into two groups with 26 patients in each. Patients in the trial group received OT and rehabilitation nursing both in hospital and after being discharged from hospital, whereas patients in the control group only received treatment in hospital. Life satisfaction was assessed when patients were discharged from hospital and 21 months later. ResultsThe patients were treated for an average of 12 weeks in hospital before being discharged. Twenty-six questionnaires were given out to the patients when they were discharged from hospital, and another 26 were given 21 months later. All the questionnaires were retrieved, with a retrieval rate of 100%. The life satisfaction scores between the trial and control groups were not different from each other when the patients were discharged from hospital (P>0.05). The trial group was more satisfied with their life 21 months after being discharged from hospital (P<0.05). The life satisfaction scores of the control group were not changed (P>0.05). The trial group had higher life satisfaction than the control group 21 months after being discharged (P<0.05). ConclusionContinuous OT instruction on patients can increase their life satisfaction, and the rehabilitation effect of patients is better than rehabilitation intervention at a certain stage.
