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BACKGROUND: Acidic fibrobiast growth factor can regulate cell proliferation, migration, differentiation and survival, also can down-regulate the known inhibitor of axon regeneration, such as proteoglycan, help axons overcome these inhibitory factors, and have significant role on the regeneration of nerve fibers.OBJECTIVE: To study the feasibility and effect of the acidic fibroblast growth factor combined with peripheral nerve transplantation in the treatment of high-level spinal cord injury in rats.METHODS: A total of adult 108 female SD rats were randomly divided into autologous nerve group, autologous nerve combined .with acidic fibroblast growth factor group, and high-level spinal cord injury group. The rat T_(8-10) spinous process and lamina were bite, revealing dural sac, high-level spinal cord was resected at a horizon level, cutting 3 mm, no nerve fibers were confirmed to be attached under the microscope. In the autogenous nerve group and autologous nerve combined with acidic fibroblast growth factor group, bilateral the 8~(th) to 10~(th) pairs of intercostal nerves were harvested 2 cm, then cross-transplanted into high-level spinal cord defect (proximal white matter and distal gray matter, distal white matter and proximal gray matter), fibrin gel and fibrin gel containing acidic fibroblast growth factor were used respectively to fix the implanted intercostal nerve, followed by dural suture.High-level spinal cord transection group was subjected to exclusion between stumps. At 90 days postoperation, somatosensory evoked potential and motor evoked potential were used to test nerve electrophysiological recovery. At 76 days postoperation,biotinylated dextran amine anterograde tracing was applied to observe the motor conduction bundle recovery. At 60 days postoperation, hindlimb motor function recovery was assessed by BBB score.RESULTS AND CONCLUSION: The somatosensory and motor evoked potential waveforms were not elicited in rats of high-level spinal cord transaction group, but did elicit in autogenous nerve group and autologous nerve combined acidic fibroblast growth factor group. The average latency and amplitude of somatosensory and motor evoked potentials, as well as BBB scores in autologous nerve combined acidic fibrobiast growth factor group were significantly superior to autologous nerve group (P ＜ 0.01).In the autogenous nerve group and autologous nerve combined acidic fibroblast growth factor group, many more biotinylated daxtran amine-positive nerve fibers passed in the damage zone, compared with high-level spinal cord transection group (P ＜0,01), the autologous nerve combined acidic fibrobiast growth factor group was more than autogenous nerve group (P ＜ 0.01). It is indicated that autologous peripheral nerve graft acidic flbroblast growth factor can better restore the limb motor functions of rats after high-level spinal cord injury.
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BACKGROUND:Present studies mainly focused on in vitro culture of bone marrow mesenchymal stem cells(BMSCs)and cell transplantation for treating intracalvarium diseases.However,the understanding of survival,differentiation,migration and structure of transplanted cells in the damaged spinal cord is limited.OBJECTIVE:To explore effects of local BMSC transplantation in repair of spinal cord damage and feasibility of replacement therapy of BMSCs.METHODS:Adult healthy female Sprague-Dawley rats were randomly assigned to cell transplantation and control groups.Rat models of spinal cord transection damage were established.Rat BMSC suspension or calcium and magnesium phosphate buffer were transplanted immediately after injury to the damage zone.At 1 day,1,2,3,4 and 8 weeks before and after transplantation,BBB score motor function was observed in rats,and at 1 week after transplantation,immunohistochemical staining was utilized to observe BrdU-labeled BMSC survival in the spinal cord damaged site.At 4 weeks after transplantation,the general observation and histological detection were observed.RESULTS AND CONCLUSION:At 1-8 weeks after transplantation,BBB scores were higher in the cell transplantation group than in the control group.At 1 week following surgery,immunohistochemical staining showed that BrdU-positive cells were detected in the distal end of rat spinal cord in the cell transplantation group.At 4 weeks following surgery,nerve fibers were found in the damaged spinal cord.These verified that BMSCs were transplanted into rat damaged spinal cord immediately following damage,and the transplanted cells could survive.Living BMSCs can differentiate into neurons,and formed neuron pathway in the local region of damage,which will promote the recovery of conduction function of spinal nerve fibers,and contribute to the recovery of rat hindlimb motor function following high-level spinal cord injury.
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@#Objective To establish C6 glioma model in rat brain and to study its biological behavior(such as the incidence of tumor development, the process of cell invasion pathological characteristics of C6 and neoangiogenesis, the spontaneous regression of experimental gliomas and the best experimental time window).Methods C6 tumor cells and DMEM were implanted into the right caudate of 50 male Wistar rats. 9 rats implanted DMEM is the control group. The animals were examined by MRI and pathological staining at postoperative day (POD) 3, 7, 14, 21,28, 35, and 50. Matrix metalloproteinases-2 (MMP-2) and CD31 immunohistochemistry staining were used to study the histopathological features of the developed tumor. Methodology, physical findings and biological behavior were also discussed. Results 45 Wistar rats survived after surgery and tolerated MRI procedures well. On POD 7, there was a focal signal at the implantation site. The C6 cells sprout to the surroundings along the nerve fiber. During the day 14～28, the tumor exhibited a marked increase in size with focal mass effect, and immunohistochemical-staining shows MMP-2 and CD31 is overexpression; C6 cells were aggregated and blood brain barrier were destroyed greatly. Most of the tumor bearing rats died within 30 days. But, C6 cells in the two rats retrogress spontaneously after more leucocytes rounded 28 days. HE staining shows tumors.Conclusion The characteristics of rat C6 brain tumor model mimicked the human tumor with respect to its development, progression, and invasion. Although, part of C6 tumor spontaneously regressed, it is a useful animal model of glioblastoma for pre-clinical evaluation of various therapeutic strategies for the management of glioblastoma. The best experimental time window is 14 to 28 days.
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Objective To evaluate the use of diffusion-weighted imaging(DWI)for early detection of tumor response to Angiostatin-Endostatin(Statin-AE)fusion gene therapy in a rat C6 glioma model.Methods Fifty male wistar rats with C6 tumor cells implanted into the striatum were examined by a 3.0T MR scanner,then the rats beating tmors were divided into two groups,treatment group and control group.Rats in the treatment group received 107 plaque forming unit(pfu)recombinant herps simplex viral (R-HSV)mediated Statin-AE fusion gene therapy on day 7,and then the tumors were conformed on MRI.Conventional MR and DWI examination were acquired on 1,2,3 weeks after implantation with a 5-inch surface coil.Two(1 w),eight(2 w)and all the residual rats(3 w)of each group were sacrificed to perform the histopathological examination after each MBI examination.Pretreatment and post treatment tumor volulnes and apparent diffusion coefficient(ADC)values were calculated.Rank sum test and t test were employed for statistical analysis.Results On MRI,43 rats demonstrated tumors on day 7 with a successful rate of 86%,On week 2,the tumor volumes of the controh and treatment group were 90.6 and 91.64 mm3,with no significant difference(Z=-0.14,P＞0.05).On week 3,the tumor volumes of the controls and treatment group were 156.64 and 29.64 mm3,and a significant difference was observed(Z=-3.45,P＜0.01).On week 2.the ADC values of the tumor centers of the treatment group and the control group were (1.20±0.25)×10-3 and(0.99±0.08)×10-3 mm2/s,and the values of the tumor peripheral parts of the two groups were(1.00±0.25)×10-3 and(0.83±0.12)×10-3mm2/s,the ADC values of both tumor centers and peripheral parts of the treatment group were significantly higher than those of the control group (t=-0.82 and-0.46,P＜0.05).On week 3,the ADC values of the tumor centers of the treatment group and the control group were(0.92±0.21)× 10-3 and(0.99±0.09)×10-3mm2/s,and the values of the tumor peripheral parts of the two groups were(0.81±0.19)×10-3 and(0.78±0.11)×10-3 mm2/a,there were no statisfical difference between the two groups(t=0.82,and-0.46,P＜0.05).HE stained slices showed more prominent tumor interstifial edenla.swelling and death of tumor cells in the treated rats than the controls.Conclusions Combination of conventional MRI and DWI can be powerful to monitor tumor progression and therapy effecL Conventional MRI showed that the therapy slow the tumor progression in size while DWI demonstrated the tumor response even earlier than size change.DWI has potential use forthe detection of early response to antiangiogenic gene therapy.